Chronic and potential non-healing wounds are a great challenge for patients, physicians, and wound care professionals and the health system. A balanced nutrition intake is essential for health as well as a speedy reco...Chronic and potential non-healing wounds are a great challenge for patients, physicians, and wound care professionals and the health system. A balanced nutrition intake is essential for health as well as a speedy recovery of such wounds. The study objective was to compare chronic wound inpatients supplemented with food nutrient content with outpatients with their usual intake in a cross-sectional study. Patients’ food samples were taken for chemical analyses. The protein, beta-carotene, sodium, magnesium, manganese, and potassium content prove statistically significant differences. Outpatients’ diets are more diversified than inpatients’ diets, and supplementation diet richest in beta-carotene and in protein. Outpatients have better dietary diversity than those who were hospitalized. The result provides insights of supplementary food as critical issues pertaining to chronic wounds management. However, analyzing bioavailability of nutrient on patients’ blood may provide more knowledge in the appropriate integrated wound management.展开更多
[Objectives]To investigate the changes in soil organic matter,nitrogen and phosphorus content in the decomposition process of Korla fragrant pear branches by indoor mixed culture.[Methods]The branches of Korla fragran...[Objectives]To investigate the changes in soil organic matter,nitrogen and phosphorus content in the decomposition process of Korla fragrant pear branches by indoor mixed culture.[Methods]The branches of Korla fragrant pear in the orchard were collected and returned to the field for a period of 150 d for indoor mixed culture.[Results]Different ages of Korla fragrant pear branches have different effects on soil nutrient content during the simulated return to field decomposition process.Compared with the control in the same period,the treatment of returning to field reached a significant level(P<0.05).Compared with the control,the average values of organic matter,total nitrogen and available phosphorus content in treatment 1 and treatment 2 increased by 2.16 times and 1.93 times,61%and 59%,5.88 times and 6.88 times,respectively;compared with the control,the average increase performance of the alkaline hydrolysis nitrogen content of the two treatments was basically the same,and the treatment 2 was the best;compared with the control,the average total phosphorus content of treatment 1 and treatment 2 increased but not significantly.[Conclusions]The contents of soil organic matter,nitrogen and phosphorus were all increased during the decomposition of pear branches,and the overall improvement effect of 10-year-old trees was better than that of 5-year-old trees.Returning the pruned branches to the field can provide a reliable theoretical basis for solving the problem of organic fertilizer shortage in orchards,and also can ensure technical support for improving soil fertility and improving the rhizosphere micro-environment of pear trees.展开更多
Garden pea productivity and qualities are hampered in zinc(Zn),boron(B),and molybdenum(Mo)deficient soil.Thus,the combination of micronutrients(i.e.,Zn,B,and Mo)and rhizobium is necessary to increase the productivity ...Garden pea productivity and qualities are hampered in zinc(Zn),boron(B),and molybdenum(Mo)deficient soil.Thus,the combination of micronutrients(i.e.,Zn,B,and Mo)and rhizobium is necessary to increase the productivity and quality of garden peas,since this management for garden peas is neglected in Bangladesh.Therefore,the present study was made to assess the effectiveness of rhizobium inoculant singly or in combination with the micronutrients(i.e.,Zn,B,and Mo)on growth,yield,nutrient uptake,and quality of garden peas.Treatments were:T_(1)=Control,T_(2)=Rhizobium inoculation at 50 g/kg seed,T_(3)=T_(2)+Zn_(3)Mo1,T_(4)=T_(2)+B_(2)Mo1,T_(5)=T_(2)+Zn_(3)B_(2),T_(6)=T_(2)+Zn_(3)B_(2)Mo1 and T_(7)=Zn_(3)B_(2)Mo1.All treatments were arranged in a randomized complete block design and repeated all treatments in three times.The application of 3 kg Zn,2 kg B,and 1 kg Mo ha^(−1)with inoculation of Rhizobium at 50 g kg^(−1)seed(T_(6))facilitated to increase of 44.8%in the green pod and 29.7%seed yield over control.The same treatment contributed to attaining the maximum nodulation(25.3 plant^(−1)),Vitamin C(43.5 mg 100 g^(−1)),protein content(22.2%),and nutrient uptake as well as accumulation in garden peas.Among all treatment combinations,treatment T_(6)was found superior to others based on microbial activities,soil fertility,and profitability.The results of the study found that the application of 3 kg Zn,2 kg B,and 1 kg Mo ha^(−1)in combination with Rhizobium inoculation(50 g kg^(−1)seed)can improve the yield and quality of garden peas.The results of the study have the potential for the areas,where there is no use of Rhizobium inoculant or Zn,B,and Mo fertilizer for cultivation of garden pea.展开更多
Flax is considered to be one of the most significant dual-purpose crops for oil and fiber production in Egypt and worldwide.Biofertilizers have a substantial impact on various metabolic processes,including increased p...Flax is considered to be one of the most significant dual-purpose crops for oil and fiber production in Egypt and worldwide.Biofertilizers have a substantial impact on various metabolic processes,including increased photo-synthesis,endogenous hormone levels,ion absorption,nucleic acid synthesis,and protein synthesis.These factors collectively contribute to the growth and development of plants.Therefore,this study aims to investigate how three biofertilizers(Algae extract,CMS as a by-product of yeast,and Metalosate multi minerals as amino acids)can enhance both the quantity and quality of flax seed yield under sandy soil conditions.Two field experiments were conducted at the Experimental Station of National Research Centre in Nubaria District,Behira Governorate,Egypt during two seasons(2021/2022)using a randomized complete block design(RCBD).The results revealed significant differences among all tested biofertilizers in terms of various characteristics studied in flax.Foliar application of algae extract at a rate of 1.50 mL/L resulted in an increase in seed yield(ton/ha)by 26.69%&19.89%,straw yield(ton/ha)by 8.08%&17.12%,and oil yield(kg/ha)by 47.72%&33.69%compared to the control group during both seasons respectively.Foliar applications of algae extract at a rate of 1.50 mL/L along with CMS at a rate of 5 m L/L and amino acids at a rate of 1.50 mL/L demonstrated significantly higher macronutrient contents(N,P,K),micronutrient contents(Fe,Zn,Mn),seed oil content,and protein content in flax seeds during both seasons.The highest values for seed oil content and protein content%were obtained through foliar application of amino acids at a rate of 1.50 mL/L.It can be concluded that foliar sprays with these bio-fertilizers effectively improved flax performance by increasing seed straw and oil yields,nutrients oil,protein and fatty acids seeds contents.展开更多
Objective: The paper aims to analyze the dynamic characteristics of litter production and nutrient return of the forest ecosystems in subtropical areas, and provide a theoretical basis for the nutrient cycling study i...Objective: The paper aims to analyze the dynamic characteristics of litter production and nutrient return of the forest ecosystems in subtropical areas, and provide a theoretical basis for the nutrient cycling study in southwest Hubei Province and carbon sink function of the whole forest ecosystem. Methods: Three typical forest stands (Chinese fir plantation, Cryptomeria fortunei plantation and evergreen and deciduous broad-leaved mixed forest) in Golden Mountain Forest Farm in southwest Hubei Province were investigated and monitored continuously for the litter types and productivity and nutrient return. Results: The annual litter productivity of the three forest stands ranged from 161.77 to 396.26 kg·hm<sup>-2</sup>;Litters of branches, leaves and reproductive organs accounted for 14.14% - 20.85%, 33.26% - 78.33%, 7.52% - 42.18% of the total, respectively;The litter productivity and total litter productivity of each composition in the three forest stands show unimodal or bimodal changes over months, and the total litter productivity reached the highest value in January, April and October respectively. For different nutrient contents of the three forest stands, the common feature is C > N. The order of nutrient return amount from greatest to least is evergreen and deciduous broad-leaved mixed forest, Cryptomeria fortunei plantation and Chinese fir plantation. For different nutrient return amounts, the common feature is C > N, and the nutrient return amounts are 76.51-180.69 kg·hm<sup>-2</sup> and 2.3 - 5.71 kg·hm<sup>-2</sup> respectively. Conclusion: The annual litter productivity and nutrient return amount of the evergreen and deciduous broad-leaved mixed forest are the highest among the three forest stands. Therefore, protecting the evergreen and deciduous broad-leaved mixed forest and studying the litter changes of Chinese fir plantation and Cryptomeria fortunei plantation are of far-reaching significance for the development of sustainable forest management in this region and the further improvement of the carbon sequestration function of the whole forest ecosystem.展开更多
Film mulching system is a widely employed agricultural practice worldwide. However, the effects of different planting and mulching patterns on soil nutrient content and enzymatic activity have not been well documented...Film mulching system is a widely employed agricultural practice worldwide. However, the effects of different planting and mulching patterns on soil nutrient content and enzymatic activity have not been well documented. In this study, we examined the impact of four planting and mulching patterns(including control, flat planting without mulching; M1, flat planting with film mulching; M2, ridge-furrow planting with film mulching on both ridges and furrows; and M3, ridge-furrow planting with film mulching on continuous ridges) on the seed yield of winter oilseed rape, soil moisture, soil temperature, soil organic carbon(SOC) content, soil nutrient content, and soil enzymatic activity over three growing seasons from 2012 to 2015 in a winter oilseed rape field in the semi-arid area of Northwest China. Seed yield of winter oilseed rape, soil moisture, soil temperature, enzymatic activities, and contents of nitrate-nitrogen, available phosphorus, and available potassium were all significantly higher in mulching treatments(M1, M2 and M3) than in control treatment over the three growing seasons, whereas SOC content was significantly lower in mulching treatments than in control treatment during 2013–2014 and 2014–2015. Among the three mulching treatments(M1, M2 and M3), the M3 treatment showed consistently higher seed yield, SOC content, nutrient contents, and enzymatic activities than the other two treatments. Seed yield of winter oilseed rape was 41.1% and 15.0% higher in M3 than in M1 and M2, respectively. SOC content and soil enzymatic activities in the top 0–20 cm soil layers and nitrate-nitrogen content in the top 0–30 cm soil layers were all significantly higher in M3 than in M1 and M2. Therefore, we advise the ridge-furrow planting with film mulching on continuous ridges(i.e., M3) as an efficient planting and mulching pattern for sustainably improving the seed yield of winter oilseed rape and preserving soil fertility in the semi-arid area of Northwest China.展开更多
A wheat variety BARI Gom 26 was cultivated with an objective of evaluating the effects of macro/secondary nutrients as S and Mg, and micro nutrients as B and Zn on yield, yield contributing traits and nutrient uptake ...A wheat variety BARI Gom 26 was cultivated with an objective of evaluating the effects of macro/secondary nutrients as S and Mg, and micro nutrients as B and Zn on yield, yield contributing traits and nutrient uptake status by the crop. The field experiment was con-ducted in the “North Eastern Barind Tract Soils” at Kushadaha, Nawabganj, Dinajpur, Bangladesh from November, 2014 to March, 2015. The surface soil was clay in texture, having pH 5.61, organic matter 1.58%, total N 0.10%, available P 7.03 ppm, exchangeable K 0.11 meq/100g, available S 2.57 ppm, exchangeable Mg 0.55 meq/100g, available Zn 1.30 ppm, available B 0.08 ppm. The experiment was designed with five treatments laid out in a randomized complete block design (RCBD) with three replications. The treatments were T1: NPK (control), T2: NPK + S, T3: NPK + S + Mg, T4: NPK + S + Mg + Zn and T5: NPK + S + Mg + Zn + B. All plots of wheat received 100 kg N/ha, 30 kg P/ha and 70 kg K/ha as basal dose. The secondary and micro nutrients doses were 15 kg S/ha, 6 kg Mg/ha, 2.5 kg Zn/ha and 1.5 kg B/ha. Results revealed that the plant height, tillers/hill, 1000-grain weight, yield of grain and straw, uptake of some specific nutrients in grain and straw were signifi-cantly influenced by all the treatments, though these treatments did not show any identical effect on spike length, content of P and Mg in wheat. Significantly highest amount of 1000-grain weight, yield of grain and straw weight of wheat were obtained in applying T2 treatment that employed the addition of S with recommended dose of NPK. Significant positive effects were also observed for the rest parameters in receiving the treatments composed of secondary and micronutrients (T3, T4, and T5). The highest concentration of nutrient uptake N, P, K and S in grain and straw of wheat were also obtained due to the application of T2 treatment. In the case of Mg, the maximum uptake was recorded in T4 where Mg was added as a component of this treatment. In contrast, the highest content of Zn and B were extracted in receiving the treatment T5 both for grain and straw. However, results suggested that T2 treatment comprising recommended dose of NPK with S might be economic and suitable as for better production of 1000-grain weight, yield of grain and straw, uptake of N, P, K and S in grain and straw of wheat cultivated in the North Eastern Barind Tract Soils of Bangladesh under winter condition. The treatment T5 would also be recommended in the context of addition of micronutrients.展开更多
[Objective]The paper was to study the effects of mowing on nutrients of forage mulberry.[Method]With forage mulberry as the research object,the effects of mowing stubbles and mowing stages on nutrient content of forag...[Objective]The paper was to study the effects of mowing on nutrients of forage mulberry.[Method]With forage mulberry as the research object,the effects of mowing stubbles and mowing stages on nutrient content of forage mulberry were studied.[Result]With the increase of mowing frequency,the crude protein and crude ash content of forage mulberry decreased,but the crude fiber content increased,and the quality of forage mulberry decreased correspondingly.The crude protein content decreased most obviously from 25.78%in the first stubble to 21.63%in the third stubble.In the first and third stubble,the nutrients at 28±1 d after the last mowing were higher than that at 38±1 d after the last mowing.That is,with the growth of forage mulberry,the accumulated nutrients were also used for their own growth.[Conclusion]From the perspective of nutrient content,the forage mulberry mowed earlier has higher nutritional value and better palatability.展开更多
[Objectives]To evaluate the status of soil nutrient and fertility in main dry farming regions of Laos,and to explore differences in soil nutrient content between regions and crop types.[Methods]By collecting 57 soil s...[Objectives]To evaluate the status of soil nutrient and fertility in main dry farming regions of Laos,and to explore differences in soil nutrient content between regions and crop types.[Methods]By collecting 57 soil samples in the 0-20 cm layer of the main dryland in southern and northern provinces of Laos.Soil pH,organic matter,total nitrogen,available nitrogen,available phosphorus,available potassium,exchangeable calcium,exchangeable magnesium and available zinc content were analyzed.[Results]The soil in the main dry farming regions of Laos was acidic,the overall fertility level was good,and the exchangeable calcium and magnesium contents were low.There were differences in soil nutrient content in the dry farming regions of southern and northern Laos.Drylands where cassava and maize were growed had higher fertility.[Conclusions]It is suggested to apply lime or alkaline fertilizer in the dry land with acid soil to increase soil pH and increase the supply of soil calcium and magnesium.Organic fertilizer should be applied to improve soil water retention capacity,and it is necessary to pay attention to the fertilization ratio of macroelements to balance fertilization.展开更多
The study was conducted to investigate the effects of applying different concentrations of the macronutrients K+,Ca2+,and Mg2+ on the responses of contrasting rice(Oryza sativa L.) genotypes under salt stress.A s...The study was conducted to investigate the effects of applying different concentrations of the macronutrients K+,Ca2+,and Mg2+ on the responses of contrasting rice(Oryza sativa L.) genotypes under salt stress.A solution culture experiment was conducted in a phytotron at the International Rice Research Institute(IRRI),under controlled temperature and humidity and natural sunlight.When subjected to salt stress of 100 mmol L-1 using NaCl,the salt tolerant genotypes FL478 and IR651,accumulated less Na+ and maintained lower ratios of Na+/K+,Na+/Ca2+,and Na+/Mg2+ than the sensitive genotypes IR29 and Azucena.These tolerant genotypes also had higher concentrations of K+ in their shoots and greater root and shoot biomass and green leaf area.Tolerant genotypes also maintained much lower concentration of Na+ and lower and more favorable ratios of Na+/K+,Na+/Ca2+,and Na+/Mg2+ in their active and developing tissues.Salt tolerance and shoot and root growth of both tolerant and sensitive genotypes were enhanced considerably when higher concentrations of Ca2+ and Mg2+ were applied in culture solution.The concentration of Na+ and the ratios of Na+/K+,Na+/Ca2+,and Na+/Mg2+ in shoots also declined significantly.The beneficial effects of higher calcium were greater than that of magnesium and application of higher concentration of K+ seems to have minor effects.Responses to salinity in rice can therefore be considerably enhanced through proper nutrient management,by increasing the concentrations of nutrient elements that have favorable effects such as Ca2+ and Mg2+.Calcium is particularly more effective than both magnesium and potassium,and can be applied at relatively larger quantities in salt affected soils.展开更多
Background:Stem CO_(2) efflux(E_(S))plays a critical role in the carbon budget of forest ecosystems.Thinning is a core practice for sustainable management of plantations.It is therefore necessary and urgent to study t...Background:Stem CO_(2) efflux(E_(S))plays a critical role in the carbon budget of forest ecosystems.Thinning is a core practice for sustainable management of plantations.It is therefore necessary and urgent to study the effect and mechanism of thinning intensity(TI)on E_(S).Methods:In this study,five TIs were applied in Larix principis-rupprechtii Mayr 21-,25-,and 41-year-old stands in North China in 2010.Portable infrared gas analyzer(Li-8100 A)was used to measure ES and its association with environmental factors at monthly intervals from May to October in 2013 to 2015.In addition,nutrients,wood structure and nonstructural carbon(NSC)data were measured in August 2016.Results:The results show that ES increased with increasing TI.The maximum ES values occurred at a TI of 35%(3.29,4.57 and 2.98μmol·m^(-2)·s^(-1))and were 1.54-,1.94-and 2.89-fold greater than the minimum E_(S) value in the CK stands(2.14,2.35 and 1.03μmol·m^(-2)·s^(-1))in July for the 21-,25-and 41-year-old forests,respectively.The E_(S) of the trees in low-density stands was more sensitive to temperature than that of the trees in high-density stands.Soluble sugars(SS)and temperature are the main factors affecting ES.When the stand density is low enough as 41-year-old L.principis-rupprechtii forests with TI 35%,bark thickness(BT)and humidity should be considered in addition to air temperature(T_(a)),wood temperature(T_(w)),sapwood width(SW),nitrogen concentration(N)and SS in the evaluation of ES.If a change in stand density is ignored,the CO_(2) released from individual 21-,25-and 41-year-old trees could be underestimated by 168.89%,101.94% and 200.49%,respectively.CO_(2) release was estimated based on the stem equation in combination with the factors influencing ES for reference.Conclusions:We suggest that it is not sufficient to conventional models which quantify ES only by temperature and that incorporating the associated drivers(e.g.density,SS,SW and N)based on stand density into conventional models can improve the accuracy of ES estimates.展开更多
The nutritional ingredients of adult Holotrichia parallela Motschulsky were analyzed comprehensively in this study.It was showed that the content of water in H.parallela was 78.39%,and the content of dry substances wa...The nutritional ingredients of adult Holotrichia parallela Motschulsky were analyzed comprehensively in this study.It was showed that the content of water in H.parallela was 78.39%,and the content of dry substances was 21.61%;among dry substances,crude protein,crude fat,ash and crude fiber accounted for 70.27%,16.26%,3.61% and 10.36%,respectively.The mineral elements,trace mineral elements and heavy metals were also determined by Microwave Digestion-Inductively Coupled Plasma Mass Spectrometry.The results indicated that the contents of major elements including potassium(K),magnesium(Mg),Calcium(Ca),iron(Fe)were rich,especially the potassium(K),up to 2 851 mg/kg.In addition,the content of copper was 8.770 167 mg/kg,and the selenium was 0.108 232 mg/kg.It was suggested that H.parallela could be used as good human food and animal feed.展开更多
The aim of the present study was to evaluate the performance of Napier cultivars in terms of forage yield, plant morphology and nutrient contents under two different agro-ecology and geo-topographic conditions. Three ...The aim of the present study was to evaluate the performance of Napier cultivars in terms of forage yield, plant morphology and nutrient contents under two different agro-ecology and geo-topographic conditions. Three Napier cultivars being conserved by Bangladesh Livestock Research Institute (BLRI), namely-BLRI</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">Napier 1, (BN-1), BLRI</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">Napier 3 (BN-3) and Merkeron (BN-5) were selected to cultivate in severe drought prone areas (called Barind) and non-drought area at Savar (Modhupur terrace). Stem cuttings were planted in rows apart from 70 cm and 35cm spacing between plants. Data of 6 consecutive harvests from a period of approximately one year were collected and analyzed statistically by “R” software. The results showed that cultivar and location had </span><span style="font-family:Verdana;">a </span><span style="font-family:Verdana;">significant (P < 0.001) effect on biomass yield, plant height and leaf-stem ratio (LSR), while number of tillers </span><span style="font-family:Verdana;">were </span><span style="font-family:Verdana;">significantly varied with locations. BN-3 yielded the highest biomass (33.32 t/ha/harvest) at non-drought location (42.98 t/ha/harvest). The highest plant height was obtained in BN-1 (171.2 cm) at non-drought location (174.6 cm). Number of tiller</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> per hill ranged from 25.4 to 26.3 among cultivars (P > 0.05) and the highest tillers were found at non-drought location (28.1 no). The best LSR was estimated from BN-5 (0.86) at drought location (0.95). The proximate analysis showed that CP, ADF and NDF in whole plant </span><span style="font-family:Verdana;">were </span><span style="font-family:Verdana;">varied significantly (P < 0.001), being the highest contents in BN-1 (10.69%, 46.20% and 54.58%, respectively). On the other hand, DM and ash contents did not differ significantly (P > 0.05) among cultivars which ranged from 15.80% to 17.13% and 13.10% to 14.58%, respectively. The highest CP content in whole plant was obtained at non-drought location (11.89%), while the lowest ash (10.57%) and NDF (52.71%) contents were obtained at the same location. The highest CP contents in leaf were found at non-drought (15.03%) and the lowest ash (9.86%) at the same location. The highest CP contents (5.90%) in stem were found at non-drought location, while the lowest ash (11.28%) and NDF (54.59%) contents </span><span style="font-family:Verdana;">were obtained </span><span style="font-family:Verdana;">at the same location. Finally, the experiment reveals the superiority in biomass yield and nutritional quality (in</span><span style="font-family:""> </span><span style="font-family:Verdana;">terms of CP content) with the ranking orders of BN-3 > BN-1 > BN-5 and BN-1 > BN-3 > BN-5. Therefore, it may be concluded that BN-1, BN-3</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> and BN-5 cultivars were well adapted in both drought and non-drought conditions, although performance showed better in later condition</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;">. However, in terms of forage yield and overall nutrient composition, the performance of BN-3 was the best irrespective of locations.展开更多
Some physicochemical characteristics of calamondin(Citrus microcarpa)from Hainan were determined in this study.The mean length,width,and thickness of calamondin were(2.763±0.262),(2.721±0.189),and(2.684±...Some physicochemical characteristics of calamondin(Citrus microcarpa)from Hainan were determined in this study.The mean length,width,and thickness of calamondin were(2.763±0.262),(2.721±0.189),and(2.684±0.201)cm,respectively.The average values for geometric mean diameter,sphericity,fruit shape index,mass,surface area,volume,true density,bulk density and porosity were(2.721±0.196)cm,(98.79±5.149)%,(101.64±7.609)%,(11.18±2.149)g,(23.36±3.362)cm2,(11.16±2.115)cm3,(1.00±0.060)g/cm3,0.44 g/cm3,and(56.40±0.027)%,respectively.The mean edible part,juice rate,and soluble solids were(85.77±3.53),(48.36±4.20),and(7.86±0.09)%,respectively.The total flavonoids,pectin,limonin,reducing sugar and volatile oil contents of the peel were 1.00,7.14,0.51,5.98,and 4.25%,respectively.The total flavonoids,pectin,limonin and reducing sugar contents of the pulp were 0.02,5.04,0.03 and 4.56%,respectively.The total flavonoids,total acid,reducing sugar and vitamin E contents of the juice were 0.11,6.74,0.37%,and 1.68 mg/kg,respectively,while the content of vitamins A,B1,B2,B3,B6,and D in the juice was very low.The seeds had limonin,reducing sugar and oil contents of 0.46,1.39,and 30.46%,respectively.The vitamin B2,B3,B6 and E contents of the fruit residue were 44.83,19.31,17.55,and 15.72 mg/kg,respectively.The amino acid profile of the residue included aspartic acid,glutamate,cystine,serine,glycine,histidine,arginine,threonine,alanine,proline,tyrosine,valine,methionine,isoleucine,leucine,phenylalanine and lysine,with respective contents of 4.42,1.81,2.10,0.78,0.59,0.20,0.72,0.160.67,3.650.50,0.67,0.59,1.00,0.76,0.57 and 0.91 g/kg.展开更多
[Objectives] This study was conducted to explore the differences in soil nutrient contents of cultivated land in different regions of Laos,and to provide a basis for soil nutrient management and scientific fertilizati...[Objectives] This study was conducted to explore the differences in soil nutrient contents of cultivated land in different regions of Laos,and to provide a basis for soil nutrient management and scientific fertilization in Laos. [Methods] By collecting 166 samples of the 0-20 cm cultivated soil layer from farmland in the farming areas of Luang Namtha Province in the northern part of Laos and Vientiane Province in the middle of the country,the contents of soil organic matter,total nitrogen,available phosphorus,available potassium,available calcium and available magnesium were analyzed,so as to evaluate the current status of soil nutrient fertility and explore the differences in soil nutrient contents of regional cultivated land. [Results] The soil organic matter was relatively abundant,the total nitrogen and available potassium contents were at the lower-middle level,and the available phosphorus,available calcium and available magnesium were insufficient or extremely insufficient. The soil nutrient contents of cultivated land were different in different regions. [Conclusions] It is suggested that lime or other alkaline fertilizers should be applied on the farmland with acid soil,and nitrogen,phosphorus,and potassium fertilizers should be added at the same time to improve soil nutrient fertility.展开更多
Biodiversity is considered a critical measure of the agricultural health of the world. Not only does increased biodiversity contribute to nutrient production and consumption, but it acts as a safeguard against food sh...Biodiversity is considered a critical measure of the agricultural health of the world. Not only does increased biodiversity contribute to nutrient production and consumption, but it acts as a safeguard against food shortages due to pests and diseases by spreading the risk. Biodiversity can improve dietary diversity in such a way to ultimately contribute to improved food and nutrition security. As a result biodiversity is often highlighted in global discussions related to food and nutrition security. Potatoes (Solanum tuberosum L.) are highly biodiverse food crops, with more than 4000 different cultivars grown globally. The crop is sometimes considered as part of the vegetable component of food baskets, but it is mainly added to meals as a starch because potatoes have a high starch content and are thus high in energy. However, significant differences in the nutritional content (including micronutrient composition) of different potato cultivars have been reported in many countries. It is therefore proposed that specific cultivars could potentially contribute more to critical nutrients required in the diet of countries at risk of malnutrition. The nutritional profile (macronutrients and minerals) of 11 potato cultivars cultivated in sub-Saharan Africa was determined and the contribution which these different potatoes could make to the diet, and consequently to food and nutrition security, is discussed. The results showed that significant differences are found in the nutritional content between the different cultivars. Significant differences (p < 0.001) were found in macronutrients such as protein and fat as well as micronutrients such as copper, phosphorus and potassium. These results indicate the potentially beneficial role which a biodiverse range of crops such as potatoes, could play in the food and nutrition security of developing countries.展开更多
Background: The global search for new ways to sequester carbon has already reached agricultural lands. Such land constitutes a major potential carbon sink. The production of high value timber within agroforestry syst...Background: The global search for new ways to sequester carbon has already reached agricultural lands. Such land constitutes a major potential carbon sink. The production of high value timber within agroforestry systems can facilitate an in-situ carbon storage function. This is followed by a potential long term ex- situ carbon sinkwithin long lasting products such as veneer and furniture. For this purpose wild cherry (Prunus avium L.) is an interesting option for middle Europe, yielding high prices on the timber market. Methods: A total number of 39 wild cherry were sampled in 2012 and 2013 to assess the leafless above ground biomass. The complete trees including stem and branches were separated into 1 cm diameter classes. Wood and bark from sub-samples were analysed separately and nutrient content was derived. Models for biomass estimation were constructed for all tree compartments. Results: The smallest diameter classes possess the highest proportion of bark due to smaller cross sectional area. Tree boles with a greater amount of stem wood above 10 cm in diameter will have a more constant bark proportion. Total branch bark proportion also remains relatively constant above dl.Bm measurements of 8 cm. A balance is evident between the production of new branches with a low diameter and high bark proportion offset by the thickening and a relative reduction in bark proportion in larger branches. The results show that a single tree with an age of 17 and 18 years can store up to 85 kg of carbon within the aboveground biomass portion, an amount that will increase as the tree matures. Branches display greater nutrient content than stem sections per volume unit which can be attributed to a greater bark proportion. Conclusions: Using the derived models the carbon and the nutrient content of above-ground woody biomass of whole trees can be calculated. Suggested values for carbon with other major and minor nutrients held within relatively immature trees strongly supports the idea of the inclusion of wild cherry within agroforestry systems as an option for carbon sequestration.展开更多
Global climate changes result in the expansion of lower elevation plants to higher elevations.The rapid upward expansion of herbaceous plants into the alpine tundra on Changbai Mountain resulted in changes in differen...Global climate changes result in the expansion of lower elevation plants to higher elevations.The rapid upward expansion of herbaceous plants into the alpine tundra on Changbai Mountain resulted in changes in different levels of ecosystem organization.However,the responses and feedback of litter properties and soil mesofauna to herbaceous plants expansion have not been studied yet.To understand the mechanisms underlying those changes,we conducted a field experiment in the range of 2250-2300 m in the alpine tundra of the Changbai Mountain and collected a total of 288 samples from four degrees of herbaceous plants expansion to study the litter physiochemical properties,soil mesofauna,and soil nutrient contents,and their relationships in that tundra ecosystem suffered from various degrees of herbaceous invasion.We found that herbaceous plant expansion is responsible for a major shift in the dominant species of soil mesofauna from mites to collembolan and has significant impacts on the community structure(R2=0.54,p=0.001)and diversity of soil mesofauna(Shannon-Weiner index,p=0.01).The increasing herbaceous plant expansion resulted in a significant increase in litter biomass from 91 g·m^(-2) in the original tundra vegetation(OIT)to 118 g·m^(-2) in the moderately invaded tundra(MIT),and an increase in litter thickness from 2.37 cm(OIT)to 3.05 cm(MIT).And,the litter total nitrogen content significantly increased,but the values of the litter carbon content,the lignin content,the C/N ratio,and the lignin/N ratio decreased with increased herbaceous coverage(both p<0.05).The litter physical properties pathway(biomass and thickness)directly explained 31% of the total variance in soil mesofauna diversity and 59% of the total variance in soil mesofauna community composition.Furthermore,both the soil available nutrients(incl.AN and AP)and plant biomass(incl.the total plant biomass and herbs/shrubs biomass)significantly increased with increasing coverage of herbaceous plant(both p<0.05),and litter chemical properties pathway directly explained 50% of the soil nutrient content variance and indirectly explained 20% of soil nutrient by affecting soil mesofauna.We found that both soil available nutrients and soil mesofauna were positively correlated with the herbaceous expansion from OIT to MIT,indicating a positive feedback of herbaceous expansion,and the abundance of soil mesofauna decreased in the severely invaded tundra vegetation,suggesting a negative feedback.While,both litter N content and soil available nitrogen were consistently increased in the severely invaded tundra vegetation,indicating a positive feedback of herbaceous expansion.Therefore,this study provides new insights into the process of herbaceous plant expansion into tundra,and provides possible evidence for further expansion according to responses and feedback of in litter properties and soil mesofauna to herbaceous plants expansion.Furthermore,these positive or/and negative feedback systems in the Changbai alpine tundra ecosystem in relation to herbaceous expansion have important implications for the tundra protection,and thus,need to be deeply studied.展开更多
Understanding the role of humic substances in soils is important for developing and utilizing organic fertilizers or soil amendments for sustainable agriculture.The objective of this study was to determine the effects...Understanding the role of humic substances in soils is important for developing and utilizing organic fertilizers or soil amendments for sustainable agriculture.The objective of this study was to determine the effects of different fractions of humic acids derived from Leonardite on enzymatic activities and bioavailability of nutrients in a soil.The experiment was carried out by mixing different factions of humic acids with a soil and incubated for 70 d.The treatments included five factions of humic acids(HS1(low molecular weight),HS2(medium molecular weight)),HS3(large molecular weight,SED(sediment of fractions),HS(mixture of HS1,HS2,and HS3)),raw Leonardite(IM)and a control(no addition of humic acid).Experimental results showed that application of humic acids significantly improved acid and alkaline phosphatase activities,especially with HS1.Humic substances with high molecular weights significantly inhibit urease activity,and the optimal application rate was 600 kg/hm2 of humic substances with the high molecular weights.Concentrations of NH4+-N were decreased with increasing humus applications.All treatments(HSmix,HS1,HS2,HS3,IM,SED)did not affect the soil contents of Ca,although soil concentrations of K,P,Cu,Zn were increase significantly when small molecular weight humus(HS1)was applied.展开更多
Rhizomes are essential organs for growth and expansion of Phragmites australis. They function as an important source of organic matter and as a nutrient source, especially in the artificial land-water transitional zon...Rhizomes are essential organs for growth and expansion of Phragmites australis. They function as an important source of organic matter and as a nutrient source, especially in the artificial land-water transitional zones (ALWTZs) of shallow lakes. In this study, decomposition experiments on 1- to 6-year-old R australis rhizomes were conducted in the ALWTZ of Lake Baiyangdian to evaluate the contribution of the rhizomes to organic matter accumulation and nutrient release. Mass loss and changes in nutrient content were measured after 3, 7, 15, 30, 60, 90, 120, and 180 days. The decomposition process was modeled with a composite exponential model. The Pearson correlation analysis was used to analyze the relationships between mass loss and litter quality factors. A multiple stepwise regression model was utilized to determine the dominant factors that affect mass loss. Results showed that the decomposition rates in water were significantly higher than those in soil for 1- to 6-year-old rhizomes. However, the sequence of decomposition rates was identical in both water and soil. Significant relationships between mass loss and litter quality factors were observed at a later stage, and P-related factors proved to have a more significant impact than N-related factors on mass loss. According to multiple stepwise models, the C/P ratio was found to be the dominant factor affecting the mass loss in water, and the C/N and C/P ratios were the main factors affecting the mass loss in soil. The combined effects of harvesting, ditch broadening, and control of water depth should be considered for lake administrators.展开更多
文摘Chronic and potential non-healing wounds are a great challenge for patients, physicians, and wound care professionals and the health system. A balanced nutrition intake is essential for health as well as a speedy recovery of such wounds. The study objective was to compare chronic wound inpatients supplemented with food nutrient content with outpatients with their usual intake in a cross-sectional study. Patients’ food samples were taken for chemical analyses. The protein, beta-carotene, sodium, magnesium, manganese, and potassium content prove statistically significant differences. Outpatients’ diets are more diversified than inpatients’ diets, and supplementation diet richest in beta-carotene and in protein. Outpatients have better dietary diversity than those who were hospitalized. The result provides insights of supplementary food as critical issues pertaining to chronic wounds management. However, analyzing bioavailability of nutrient on patients’ blood may provide more knowledge in the appropriate integrated wound management.
基金Supported by Key R&D Program of Hainan Province in 2021(ZDYF2021XDNY152).
文摘[Objectives]To investigate the changes in soil organic matter,nitrogen and phosphorus content in the decomposition process of Korla fragrant pear branches by indoor mixed culture.[Methods]The branches of Korla fragrant pear in the orchard were collected and returned to the field for a period of 150 d for indoor mixed culture.[Results]Different ages of Korla fragrant pear branches have different effects on soil nutrient content during the simulated return to field decomposition process.Compared with the control in the same period,the treatment of returning to field reached a significant level(P<0.05).Compared with the control,the average values of organic matter,total nitrogen and available phosphorus content in treatment 1 and treatment 2 increased by 2.16 times and 1.93 times,61%and 59%,5.88 times and 6.88 times,respectively;compared with the control,the average increase performance of the alkaline hydrolysis nitrogen content of the two treatments was basically the same,and the treatment 2 was the best;compared with the control,the average total phosphorus content of treatment 1 and treatment 2 increased but not significantly.[Conclusions]The contents of soil organic matter,nitrogen and phosphorus were all increased during the decomposition of pear branches,and the overall improvement effect of 10-year-old trees was better than that of 5-year-old trees.Returning the pruned branches to the field can provide a reliable theoretical basis for solving the problem of organic fertilizer shortage in orchards,and also can ensure technical support for improving soil fertility and improving the rhizosphere micro-environment of pear trees.
文摘Garden pea productivity and qualities are hampered in zinc(Zn),boron(B),and molybdenum(Mo)deficient soil.Thus,the combination of micronutrients(i.e.,Zn,B,and Mo)and rhizobium is necessary to increase the productivity and quality of garden peas,since this management for garden peas is neglected in Bangladesh.Therefore,the present study was made to assess the effectiveness of rhizobium inoculant singly or in combination with the micronutrients(i.e.,Zn,B,and Mo)on growth,yield,nutrient uptake,and quality of garden peas.Treatments were:T_(1)=Control,T_(2)=Rhizobium inoculation at 50 g/kg seed,T_(3)=T_(2)+Zn_(3)Mo1,T_(4)=T_(2)+B_(2)Mo1,T_(5)=T_(2)+Zn_(3)B_(2),T_(6)=T_(2)+Zn_(3)B_(2)Mo1 and T_(7)=Zn_(3)B_(2)Mo1.All treatments were arranged in a randomized complete block design and repeated all treatments in three times.The application of 3 kg Zn,2 kg B,and 1 kg Mo ha^(−1)with inoculation of Rhizobium at 50 g kg^(−1)seed(T_(6))facilitated to increase of 44.8%in the green pod and 29.7%seed yield over control.The same treatment contributed to attaining the maximum nodulation(25.3 plant^(−1)),Vitamin C(43.5 mg 100 g^(−1)),protein content(22.2%),and nutrient uptake as well as accumulation in garden peas.Among all treatment combinations,treatment T_(6)was found superior to others based on microbial activities,soil fertility,and profitability.The results of the study found that the application of 3 kg Zn,2 kg B,and 1 kg Mo ha^(−1)in combination with Rhizobium inoculation(50 g kg^(−1)seed)can improve the yield and quality of garden peas.The results of the study have the potential for the areas,where there is no use of Rhizobium inoculant or Zn,B,and Mo fertilizer for cultivation of garden pea.
基金the National Research Centre(NRC),Egypt,for providing funding for this student research。
文摘Flax is considered to be one of the most significant dual-purpose crops for oil and fiber production in Egypt and worldwide.Biofertilizers have a substantial impact on various metabolic processes,including increased photo-synthesis,endogenous hormone levels,ion absorption,nucleic acid synthesis,and protein synthesis.These factors collectively contribute to the growth and development of plants.Therefore,this study aims to investigate how three biofertilizers(Algae extract,CMS as a by-product of yeast,and Metalosate multi minerals as amino acids)can enhance both the quantity and quality of flax seed yield under sandy soil conditions.Two field experiments were conducted at the Experimental Station of National Research Centre in Nubaria District,Behira Governorate,Egypt during two seasons(2021/2022)using a randomized complete block design(RCBD).The results revealed significant differences among all tested biofertilizers in terms of various characteristics studied in flax.Foliar application of algae extract at a rate of 1.50 mL/L resulted in an increase in seed yield(ton/ha)by 26.69%&19.89%,straw yield(ton/ha)by 8.08%&17.12%,and oil yield(kg/ha)by 47.72%&33.69%compared to the control group during both seasons respectively.Foliar applications of algae extract at a rate of 1.50 mL/L along with CMS at a rate of 5 m L/L and amino acids at a rate of 1.50 mL/L demonstrated significantly higher macronutrient contents(N,P,K),micronutrient contents(Fe,Zn,Mn),seed oil content,and protein content in flax seeds during both seasons.The highest values for seed oil content and protein content%were obtained through foliar application of amino acids at a rate of 1.50 mL/L.It can be concluded that foliar sprays with these bio-fertilizers effectively improved flax performance by increasing seed straw and oil yields,nutrients oil,protein and fatty acids seeds contents.
文摘Objective: The paper aims to analyze the dynamic characteristics of litter production and nutrient return of the forest ecosystems in subtropical areas, and provide a theoretical basis for the nutrient cycling study in southwest Hubei Province and carbon sink function of the whole forest ecosystem. Methods: Three typical forest stands (Chinese fir plantation, Cryptomeria fortunei plantation and evergreen and deciduous broad-leaved mixed forest) in Golden Mountain Forest Farm in southwest Hubei Province were investigated and monitored continuously for the litter types and productivity and nutrient return. Results: The annual litter productivity of the three forest stands ranged from 161.77 to 396.26 kg·hm<sup>-2</sup>;Litters of branches, leaves and reproductive organs accounted for 14.14% - 20.85%, 33.26% - 78.33%, 7.52% - 42.18% of the total, respectively;The litter productivity and total litter productivity of each composition in the three forest stands show unimodal or bimodal changes over months, and the total litter productivity reached the highest value in January, April and October respectively. For different nutrient contents of the three forest stands, the common feature is C > N. The order of nutrient return amount from greatest to least is evergreen and deciduous broad-leaved mixed forest, Cryptomeria fortunei plantation and Chinese fir plantation. For different nutrient return amounts, the common feature is C > N, and the nutrient return amounts are 76.51-180.69 kg·hm<sup>-2</sup> and 2.3 - 5.71 kg·hm<sup>-2</sup> respectively. Conclusion: The annual litter productivity and nutrient return amount of the evergreen and deciduous broad-leaved mixed forest are the highest among the three forest stands. Therefore, protecting the evergreen and deciduous broad-leaved mixed forest and studying the litter changes of Chinese fir plantation and Cryptomeria fortunei plantation are of far-reaching significance for the development of sustainable forest management in this region and the further improvement of the carbon sequestration function of the whole forest ecosystem.
基金supported by the Special Fund for Agro-scientific Research in the Public Interest,China (201503125,201503105)the National High Technology Research and Development Program of China (2011AA100504)
文摘Film mulching system is a widely employed agricultural practice worldwide. However, the effects of different planting and mulching patterns on soil nutrient content and enzymatic activity have not been well documented. In this study, we examined the impact of four planting and mulching patterns(including control, flat planting without mulching; M1, flat planting with film mulching; M2, ridge-furrow planting with film mulching on both ridges and furrows; and M3, ridge-furrow planting with film mulching on continuous ridges) on the seed yield of winter oilseed rape, soil moisture, soil temperature, soil organic carbon(SOC) content, soil nutrient content, and soil enzymatic activity over three growing seasons from 2012 to 2015 in a winter oilseed rape field in the semi-arid area of Northwest China. Seed yield of winter oilseed rape, soil moisture, soil temperature, enzymatic activities, and contents of nitrate-nitrogen, available phosphorus, and available potassium were all significantly higher in mulching treatments(M1, M2 and M3) than in control treatment over the three growing seasons, whereas SOC content was significantly lower in mulching treatments than in control treatment during 2013–2014 and 2014–2015. Among the three mulching treatments(M1, M2 and M3), the M3 treatment showed consistently higher seed yield, SOC content, nutrient contents, and enzymatic activities than the other two treatments. Seed yield of winter oilseed rape was 41.1% and 15.0% higher in M3 than in M1 and M2, respectively. SOC content and soil enzymatic activities in the top 0–20 cm soil layers and nitrate-nitrogen content in the top 0–30 cm soil layers were all significantly higher in M3 than in M1 and M2. Therefore, we advise the ridge-furrow planting with film mulching on continuous ridges(i.e., M3) as an efficient planting and mulching pattern for sustainably improving the seed yield of winter oilseed rape and preserving soil fertility in the semi-arid area of Northwest China.
文摘A wheat variety BARI Gom 26 was cultivated with an objective of evaluating the effects of macro/secondary nutrients as S and Mg, and micro nutrients as B and Zn on yield, yield contributing traits and nutrient uptake status by the crop. The field experiment was con-ducted in the “North Eastern Barind Tract Soils” at Kushadaha, Nawabganj, Dinajpur, Bangladesh from November, 2014 to March, 2015. The surface soil was clay in texture, having pH 5.61, organic matter 1.58%, total N 0.10%, available P 7.03 ppm, exchangeable K 0.11 meq/100g, available S 2.57 ppm, exchangeable Mg 0.55 meq/100g, available Zn 1.30 ppm, available B 0.08 ppm. The experiment was designed with five treatments laid out in a randomized complete block design (RCBD) with three replications. The treatments were T1: NPK (control), T2: NPK + S, T3: NPK + S + Mg, T4: NPK + S + Mg + Zn and T5: NPK + S + Mg + Zn + B. All plots of wheat received 100 kg N/ha, 30 kg P/ha and 70 kg K/ha as basal dose. The secondary and micro nutrients doses were 15 kg S/ha, 6 kg Mg/ha, 2.5 kg Zn/ha and 1.5 kg B/ha. Results revealed that the plant height, tillers/hill, 1000-grain weight, yield of grain and straw, uptake of some specific nutrients in grain and straw were signifi-cantly influenced by all the treatments, though these treatments did not show any identical effect on spike length, content of P and Mg in wheat. Significantly highest amount of 1000-grain weight, yield of grain and straw weight of wheat were obtained in applying T2 treatment that employed the addition of S with recommended dose of NPK. Significant positive effects were also observed for the rest parameters in receiving the treatments composed of secondary and micronutrients (T3, T4, and T5). The highest concentration of nutrient uptake N, P, K and S in grain and straw of wheat were also obtained due to the application of T2 treatment. In the case of Mg, the maximum uptake was recorded in T4 where Mg was added as a component of this treatment. In contrast, the highest content of Zn and B were extracted in receiving the treatment T5 both for grain and straw. However, results suggested that T2 treatment comprising recommended dose of NPK with S might be economic and suitable as for better production of 1000-grain weight, yield of grain and straw, uptake of N, P, K and S in grain and straw of wheat cultivated in the North Eastern Barind Tract Soils of Bangladesh under winter condition. The treatment T5 would also be recommended in the context of addition of micronutrients.
基金Supported by Performance Incentive and Guidance Special Project of Scientific Research Institutes in Chongqing City(19537)Special Research and Development Project of Chongqing Rongchang Agriculture and Animal Husbandry High-tech Industry(20209)Diversification Development Research Office of Chongqing Modern Mountain Characteristic Benefit Agriculture(Sericulture)Technology System(18304).
文摘[Objective]The paper was to study the effects of mowing on nutrients of forage mulberry.[Method]With forage mulberry as the research object,the effects of mowing stubbles and mowing stages on nutrient content of forage mulberry were studied.[Result]With the increase of mowing frequency,the crude protein and crude ash content of forage mulberry decreased,but the crude fiber content increased,and the quality of forage mulberry decreased correspondingly.The crude protein content decreased most obviously from 25.78%in the first stubble to 21.63%in the third stubble.In the first and third stubble,the nutrients at 28±1 d after the last mowing were higher than that at 38±1 d after the last mowing.That is,with the growth of forage mulberry,the accumulated nutrients were also used for their own growth.[Conclusion]From the perspective of nutrient content,the forage mulberry mowed earlier has higher nutritional value and better palatability.
基金Guangxi Science and Technology Plan Project(Gui Ke AD17195026&Gui Ke AD19259007)Science and Technology Development Fund Project of Guangxi Academy of Agricultural Sciences(Gui Nong Ke 2016ZX11)Fund Project of Guangxi Academy of Agricultural Sciences(2019ZX121).
文摘[Objectives]To evaluate the status of soil nutrient and fertility in main dry farming regions of Laos,and to explore differences in soil nutrient content between regions and crop types.[Methods]By collecting 57 soil samples in the 0-20 cm layer of the main dryland in southern and northern provinces of Laos.Soil pH,organic matter,total nitrogen,available nitrogen,available phosphorus,available potassium,exchangeable calcium,exchangeable magnesium and available zinc content were analyzed.[Results]The soil in the main dry farming regions of Laos was acidic,the overall fertility level was good,and the exchangeable calcium and magnesium contents were low.There were differences in soil nutrient content in the dry farming regions of southern and northern Laos.Drylands where cassava and maize were growed had higher fertility.[Conclusions]It is suggested to apply lime or alkaline fertilizer in the dry land with acid soil to increase soil pH and increase the supply of soil calcium and magnesium.Organic fertilizer should be applied to improve soil water retention capacity,and it is necessary to pay attention to the fertilization ratio of macroelements to balance fertilization.
基金the National Key Technology R&D Program of China(2007BAD87B11)the 948 Program,Minsitry of Agriculture,China (200803030)
文摘The study was conducted to investigate the effects of applying different concentrations of the macronutrients K+,Ca2+,and Mg2+ on the responses of contrasting rice(Oryza sativa L.) genotypes under salt stress.A solution culture experiment was conducted in a phytotron at the International Rice Research Institute(IRRI),under controlled temperature and humidity and natural sunlight.When subjected to salt stress of 100 mmol L-1 using NaCl,the salt tolerant genotypes FL478 and IR651,accumulated less Na+ and maintained lower ratios of Na+/K+,Na+/Ca2+,and Na+/Mg2+ than the sensitive genotypes IR29 and Azucena.These tolerant genotypes also had higher concentrations of K+ in their shoots and greater root and shoot biomass and green leaf area.Tolerant genotypes also maintained much lower concentration of Na+ and lower and more favorable ratios of Na+/K+,Na+/Ca2+,and Na+/Mg2+ in their active and developing tissues.Salt tolerance and shoot and root growth of both tolerant and sensitive genotypes were enhanced considerably when higher concentrations of Ca2+ and Mg2+ were applied in culture solution.The concentration of Na+ and the ratios of Na+/K+,Na+/Ca2+,and Na+/Mg2+ in shoots also declined significantly.The beneficial effects of higher calcium were greater than that of magnesium and application of higher concentration of K+ seems to have minor effects.Responses to salinity in rice can therefore be considerably enhanced through proper nutrient management,by increasing the concentrations of nutrient elements that have favorable effects such as Ca2+ and Mg2+.Calcium is particularly more effective than both magnesium and potassium,and can be applied at relatively larger quantities in salt affected soils.
基金funding from National Natural Science Foundation of China(No.31870387),China Scholarship Council.
文摘Background:Stem CO_(2) efflux(E_(S))plays a critical role in the carbon budget of forest ecosystems.Thinning is a core practice for sustainable management of plantations.It is therefore necessary and urgent to study the effect and mechanism of thinning intensity(TI)on E_(S).Methods:In this study,five TIs were applied in Larix principis-rupprechtii Mayr 21-,25-,and 41-year-old stands in North China in 2010.Portable infrared gas analyzer(Li-8100 A)was used to measure ES and its association with environmental factors at monthly intervals from May to October in 2013 to 2015.In addition,nutrients,wood structure and nonstructural carbon(NSC)data were measured in August 2016.Results:The results show that ES increased with increasing TI.The maximum ES values occurred at a TI of 35%(3.29,4.57 and 2.98μmol·m^(-2)·s^(-1))and were 1.54-,1.94-and 2.89-fold greater than the minimum E_(S) value in the CK stands(2.14,2.35 and 1.03μmol·m^(-2)·s^(-1))in July for the 21-,25-and 41-year-old forests,respectively.The E_(S) of the trees in low-density stands was more sensitive to temperature than that of the trees in high-density stands.Soluble sugars(SS)and temperature are the main factors affecting ES.When the stand density is low enough as 41-year-old L.principis-rupprechtii forests with TI 35%,bark thickness(BT)and humidity should be considered in addition to air temperature(T_(a)),wood temperature(T_(w)),sapwood width(SW),nitrogen concentration(N)and SS in the evaluation of ES.If a change in stand density is ignored,the CO_(2) released from individual 21-,25-and 41-year-old trees could be underestimated by 168.89%,101.94% and 200.49%,respectively.CO_(2) release was estimated based on the stem equation in combination with the factors influencing ES for reference.Conclusions:We suggest that it is not sufficient to conventional models which quantify ES only by temperature and that incorporating the associated drivers(e.g.density,SS,SW and N)based on stand density into conventional models can improve the accuracy of ES estimates.
文摘The nutritional ingredients of adult Holotrichia parallela Motschulsky were analyzed comprehensively in this study.It was showed that the content of water in H.parallela was 78.39%,and the content of dry substances was 21.61%;among dry substances,crude protein,crude fat,ash and crude fiber accounted for 70.27%,16.26%,3.61% and 10.36%,respectively.The mineral elements,trace mineral elements and heavy metals were also determined by Microwave Digestion-Inductively Coupled Plasma Mass Spectrometry.The results indicated that the contents of major elements including potassium(K),magnesium(Mg),Calcium(Ca),iron(Fe)were rich,especially the potassium(K),up to 2 851 mg/kg.In addition,the content of copper was 8.770 167 mg/kg,and the selenium was 0.108 232 mg/kg.It was suggested that H.parallela could be used as good human food and animal feed.
文摘The aim of the present study was to evaluate the performance of Napier cultivars in terms of forage yield, plant morphology and nutrient contents under two different agro-ecology and geo-topographic conditions. Three Napier cultivars being conserved by Bangladesh Livestock Research Institute (BLRI), namely-BLRI</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">Napier 1, (BN-1), BLRI</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">Napier 3 (BN-3) and Merkeron (BN-5) were selected to cultivate in severe drought prone areas (called Barind) and non-drought area at Savar (Modhupur terrace). Stem cuttings were planted in rows apart from 70 cm and 35cm spacing between plants. Data of 6 consecutive harvests from a period of approximately one year were collected and analyzed statistically by “R” software. The results showed that cultivar and location had </span><span style="font-family:Verdana;">a </span><span style="font-family:Verdana;">significant (P < 0.001) effect on biomass yield, plant height and leaf-stem ratio (LSR), while number of tillers </span><span style="font-family:Verdana;">were </span><span style="font-family:Verdana;">significantly varied with locations. BN-3 yielded the highest biomass (33.32 t/ha/harvest) at non-drought location (42.98 t/ha/harvest). The highest plant height was obtained in BN-1 (171.2 cm) at non-drought location (174.6 cm). Number of tiller</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> per hill ranged from 25.4 to 26.3 among cultivars (P > 0.05) and the highest tillers were found at non-drought location (28.1 no). The best LSR was estimated from BN-5 (0.86) at drought location (0.95). The proximate analysis showed that CP, ADF and NDF in whole plant </span><span style="font-family:Verdana;">were </span><span style="font-family:Verdana;">varied significantly (P < 0.001), being the highest contents in BN-1 (10.69%, 46.20% and 54.58%, respectively). On the other hand, DM and ash contents did not differ significantly (P > 0.05) among cultivars which ranged from 15.80% to 17.13% and 13.10% to 14.58%, respectively. The highest CP content in whole plant was obtained at non-drought location (11.89%), while the lowest ash (10.57%) and NDF (52.71%) contents were obtained at the same location. The highest CP contents in leaf were found at non-drought (15.03%) and the lowest ash (9.86%) at the same location. The highest CP contents (5.90%) in stem were found at non-drought location, while the lowest ash (11.28%) and NDF (54.59%) contents </span><span style="font-family:Verdana;">were obtained </span><span style="font-family:Verdana;">at the same location. Finally, the experiment reveals the superiority in biomass yield and nutritional quality (in</span><span style="font-family:""> </span><span style="font-family:Verdana;">terms of CP content) with the ranking orders of BN-3 > BN-1 > BN-5 and BN-1 > BN-3 > BN-5. Therefore, it may be concluded that BN-1, BN-3</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> and BN-5 cultivars were well adapted in both drought and non-drought conditions, although performance showed better in later condition</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;">. However, in terms of forage yield and overall nutrient composition, the performance of BN-3 was the best irrespective of locations.
基金Technical Development Project of Provincial Scientific Research Institutes in Hainan(KYYS-2019-30)Technical Innovation Project of Provincial Scientific Research Institutes in Hainan(jscx202034).
文摘Some physicochemical characteristics of calamondin(Citrus microcarpa)from Hainan were determined in this study.The mean length,width,and thickness of calamondin were(2.763±0.262),(2.721±0.189),and(2.684±0.201)cm,respectively.The average values for geometric mean diameter,sphericity,fruit shape index,mass,surface area,volume,true density,bulk density and porosity were(2.721±0.196)cm,(98.79±5.149)%,(101.64±7.609)%,(11.18±2.149)g,(23.36±3.362)cm2,(11.16±2.115)cm3,(1.00±0.060)g/cm3,0.44 g/cm3,and(56.40±0.027)%,respectively.The mean edible part,juice rate,and soluble solids were(85.77±3.53),(48.36±4.20),and(7.86±0.09)%,respectively.The total flavonoids,pectin,limonin,reducing sugar and volatile oil contents of the peel were 1.00,7.14,0.51,5.98,and 4.25%,respectively.The total flavonoids,pectin,limonin and reducing sugar contents of the pulp were 0.02,5.04,0.03 and 4.56%,respectively.The total flavonoids,total acid,reducing sugar and vitamin E contents of the juice were 0.11,6.74,0.37%,and 1.68 mg/kg,respectively,while the content of vitamins A,B1,B2,B3,B6,and D in the juice was very low.The seeds had limonin,reducing sugar and oil contents of 0.46,1.39,and 30.46%,respectively.The vitamin B2,B3,B6 and E contents of the fruit residue were 44.83,19.31,17.55,and 15.72 mg/kg,respectively.The amino acid profile of the residue included aspartic acid,glutamate,cystine,serine,glycine,histidine,arginine,threonine,alanine,proline,tyrosine,valine,methionine,isoleucine,leucine,phenylalanine and lysine,with respective contents of 4.42,1.81,2.10,0.78,0.59,0.20,0.72,0.160.67,3.650.50,0.67,0.59,1.00,0.76,0.57 and 0.91 g/kg.
基金Supported by Guangxi R&D Project (Gui Ke-AD17195026)Fund of Guangxi Academy of Agricultural Sciences (2019ZX121)。
文摘[Objectives] This study was conducted to explore the differences in soil nutrient contents of cultivated land in different regions of Laos,and to provide a basis for soil nutrient management and scientific fertilization in Laos. [Methods] By collecting 166 samples of the 0-20 cm cultivated soil layer from farmland in the farming areas of Luang Namtha Province in the northern part of Laos and Vientiane Province in the middle of the country,the contents of soil organic matter,total nitrogen,available phosphorus,available potassium,available calcium and available magnesium were analyzed,so as to evaluate the current status of soil nutrient fertility and explore the differences in soil nutrient contents of regional cultivated land. [Results] The soil organic matter was relatively abundant,the total nitrogen and available potassium contents were at the lower-middle level,and the available phosphorus,available calcium and available magnesium were insufficient or extremely insufficient. The soil nutrient contents of cultivated land were different in different regions. [Conclusions] It is suggested that lime or other alkaline fertilizers should be applied on the farmland with acid soil,and nitrogen,phosphorus,and potassium fertilizers should be added at the same time to improve soil nutrient fertility.
文摘Biodiversity is considered a critical measure of the agricultural health of the world. Not only does increased biodiversity contribute to nutrient production and consumption, but it acts as a safeguard against food shortages due to pests and diseases by spreading the risk. Biodiversity can improve dietary diversity in such a way to ultimately contribute to improved food and nutrition security. As a result biodiversity is often highlighted in global discussions related to food and nutrition security. Potatoes (Solanum tuberosum L.) are highly biodiverse food crops, with more than 4000 different cultivars grown globally. The crop is sometimes considered as part of the vegetable component of food baskets, but it is mainly added to meals as a starch because potatoes have a high starch content and are thus high in energy. However, significant differences in the nutritional content (including micronutrient composition) of different potato cultivars have been reported in many countries. It is therefore proposed that specific cultivars could potentially contribute more to critical nutrients required in the diet of countries at risk of malnutrition. The nutritional profile (macronutrients and minerals) of 11 potato cultivars cultivated in sub-Saharan Africa was determined and the contribution which these different potatoes could make to the diet, and consequently to food and nutrition security, is discussed. The results showed that significant differences are found in the nutritional content between the different cultivars. Significant differences (p < 0.001) were found in macronutrients such as protein and fat as well as micronutrients such as copper, phosphorus and potassium. These results indicate the potentially beneficial role which a biodiverse range of crops such as potatoes, could play in the food and nutrition security of developing countries.
基金supported by the EU FP7 project StarTree(Grant Agreement Number 311919)the Federal Ministry of Education and Research(BMBF) within the AGROCOP project (support code 033L051B)the German Federal Ministry of Food and Agriculture(BMEL) within the project Agro-Wertholz(support code 22031112)
文摘Background: The global search for new ways to sequester carbon has already reached agricultural lands. Such land constitutes a major potential carbon sink. The production of high value timber within agroforestry systems can facilitate an in-situ carbon storage function. This is followed by a potential long term ex- situ carbon sinkwithin long lasting products such as veneer and furniture. For this purpose wild cherry (Prunus avium L.) is an interesting option for middle Europe, yielding high prices on the timber market. Methods: A total number of 39 wild cherry were sampled in 2012 and 2013 to assess the leafless above ground biomass. The complete trees including stem and branches were separated into 1 cm diameter classes. Wood and bark from sub-samples were analysed separately and nutrient content was derived. Models for biomass estimation were constructed for all tree compartments. Results: The smallest diameter classes possess the highest proportion of bark due to smaller cross sectional area. Tree boles with a greater amount of stem wood above 10 cm in diameter will have a more constant bark proportion. Total branch bark proportion also remains relatively constant above dl.Bm measurements of 8 cm. A balance is evident between the production of new branches with a low diameter and high bark proportion offset by the thickening and a relative reduction in bark proportion in larger branches. The results show that a single tree with an age of 17 and 18 years can store up to 85 kg of carbon within the aboveground biomass portion, an amount that will increase as the tree matures. Branches display greater nutrient content than stem sections per volume unit which can be attributed to a greater bark proportion. Conclusions: Using the derived models the carbon and the nutrient content of above-ground woody biomass of whole trees can be calculated. Suggested values for carbon with other major and minor nutrients held within relatively immature trees strongly supports the idea of the inclusion of wild cherry within agroforestry systems as an option for carbon sequestration.
基金funded by the Natural Science Foundation of China(Grants No.41571078 and 41171072)。
文摘Global climate changes result in the expansion of lower elevation plants to higher elevations.The rapid upward expansion of herbaceous plants into the alpine tundra on Changbai Mountain resulted in changes in different levels of ecosystem organization.However,the responses and feedback of litter properties and soil mesofauna to herbaceous plants expansion have not been studied yet.To understand the mechanisms underlying those changes,we conducted a field experiment in the range of 2250-2300 m in the alpine tundra of the Changbai Mountain and collected a total of 288 samples from four degrees of herbaceous plants expansion to study the litter physiochemical properties,soil mesofauna,and soil nutrient contents,and their relationships in that tundra ecosystem suffered from various degrees of herbaceous invasion.We found that herbaceous plant expansion is responsible for a major shift in the dominant species of soil mesofauna from mites to collembolan and has significant impacts on the community structure(R2=0.54,p=0.001)and diversity of soil mesofauna(Shannon-Weiner index,p=0.01).The increasing herbaceous plant expansion resulted in a significant increase in litter biomass from 91 g·m^(-2) in the original tundra vegetation(OIT)to 118 g·m^(-2) in the moderately invaded tundra(MIT),and an increase in litter thickness from 2.37 cm(OIT)to 3.05 cm(MIT).And,the litter total nitrogen content significantly increased,but the values of the litter carbon content,the lignin content,the C/N ratio,and the lignin/N ratio decreased with increased herbaceous coverage(both p<0.05).The litter physical properties pathway(biomass and thickness)directly explained 31% of the total variance in soil mesofauna diversity and 59% of the total variance in soil mesofauna community composition.Furthermore,both the soil available nutrients(incl.AN and AP)and plant biomass(incl.the total plant biomass and herbs/shrubs biomass)significantly increased with increasing coverage of herbaceous plant(both p<0.05),and litter chemical properties pathway directly explained 50% of the soil nutrient content variance and indirectly explained 20% of soil nutrient by affecting soil mesofauna.We found that both soil available nutrients and soil mesofauna were positively correlated with the herbaceous expansion from OIT to MIT,indicating a positive feedback of herbaceous expansion,and the abundance of soil mesofauna decreased in the severely invaded tundra vegetation,suggesting a negative feedback.While,both litter N content and soil available nitrogen were consistently increased in the severely invaded tundra vegetation,indicating a positive feedback of herbaceous expansion.Therefore,this study provides new insights into the process of herbaceous plant expansion into tundra,and provides possible evidence for further expansion according to responses and feedback of in litter properties and soil mesofauna to herbaceous plants expansion.Furthermore,these positive or/and negative feedback systems in the Changbai alpine tundra ecosystem in relation to herbaceous expansion have important implications for the tundra protection,and thus,need to be deeply studied.
基金Funding was provided by the Natural Science Foundation of Jiangsu Province(BK20170614)National Natural Science Foundation of China(NO.61803187,31901419)Jiangsu Agriculture Science and Technology Innovation Fund(CX(18)3047).
文摘Understanding the role of humic substances in soils is important for developing and utilizing organic fertilizers or soil amendments for sustainable agriculture.The objective of this study was to determine the effects of different fractions of humic acids derived from Leonardite on enzymatic activities and bioavailability of nutrients in a soil.The experiment was carried out by mixing different factions of humic acids with a soil and incubated for 70 d.The treatments included five factions of humic acids(HS1(low molecular weight),HS2(medium molecular weight)),HS3(large molecular weight,SED(sediment of fractions),HS(mixture of HS1,HS2,and HS3)),raw Leonardite(IM)and a control(no addition of humic acid).Experimental results showed that application of humic acids significantly improved acid and alkaline phosphatase activities,especially with HS1.Humic substances with high molecular weights significantly inhibit urease activity,and the optimal application rate was 600 kg/hm2 of humic substances with the high molecular weights.Concentrations of NH4+-N were decreased with increasing humus applications.All treatments(HSmix,HS1,HS2,HS3,IM,SED)did not affect the soil contents of Ca,although soil concentrations of K,P,Cu,Zn were increase significantly when small molecular weight humus(HS1)was applied.
文摘Rhizomes are essential organs for growth and expansion of Phragmites australis. They function as an important source of organic matter and as a nutrient source, especially in the artificial land-water transitional zones (ALWTZs) of shallow lakes. In this study, decomposition experiments on 1- to 6-year-old R australis rhizomes were conducted in the ALWTZ of Lake Baiyangdian to evaluate the contribution of the rhizomes to organic matter accumulation and nutrient release. Mass loss and changes in nutrient content were measured after 3, 7, 15, 30, 60, 90, 120, and 180 days. The decomposition process was modeled with a composite exponential model. The Pearson correlation analysis was used to analyze the relationships between mass loss and litter quality factors. A multiple stepwise regression model was utilized to determine the dominant factors that affect mass loss. Results showed that the decomposition rates in water were significantly higher than those in soil for 1- to 6-year-old rhizomes. However, the sequence of decomposition rates was identical in both water and soil. Significant relationships between mass loss and litter quality factors were observed at a later stage, and P-related factors proved to have a more significant impact than N-related factors on mass loss. According to multiple stepwise models, the C/P ratio was found to be the dominant factor affecting the mass loss in water, and the C/N and C/P ratios were the main factors affecting the mass loss in soil. The combined effects of harvesting, ditch broadening, and control of water depth should be considered for lake administrators.