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Available Contents of Trace Nutrient Element and Factors Affecting Their Availability in Western Jilin 被引量:4
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作者 施宪 王冬艳 +2 位作者 李月芬 靳克 郭珍 《Agricultural Science & Technology》 CAS 2010年第5期73-76,共4页
Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient ele... Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient elements and their affecting factors are studied. The results show that the available B in western Jilin is in a middle level,the content in Nong'an is higher than that in the others; the available Mn is extremely abundant; the available Cu in Nong'an is obviously higher than other areas,and the content in Da'an differs greatly; the available Zn is in a middle level; the severe shortage of available Mo differs between different areas; and the available Fe is extremely abundant. The available Mn,Cu and Fe have significantly positive correlation with their total content; the available B has significantly positive correlation with pH,and Zn has obviously negative correlation with pH; the available Mn and Fe had significantly positive correlation with soil organic matter. 展开更多
关键词 Trace nutrient element available content The affecting factors Western Jilin
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Effects of Biochar and Soil Organic Matter Levels on Physicochemical Properties of Mollisol and Soybean's Biomass
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作者 Zhang Shuaikun Xu Zhiyuan +4 位作者 Shi Fangfang Yang Jing Luo Xu Jiang Zhenfeng Liu Zhihua 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第3期33-41,共9页
Long term tillage in mollisol of Northeast China has led to an inhomogeneous distribution of soil organic matter content.Biochar,a carbon material,changes the soil carbon pool and physical-chemical characteristics aft... Long term tillage in mollisol of Northeast China has led to an inhomogeneous distribution of soil organic matter content.Biochar,a carbon material,changes the soil carbon pool and physical-chemical characteristics after adding to the soil.However,the mechanism remains unclear for the relation between the soil organic matter level and biochar amount.So,the soil physical and chemical properties and soybean growth in a two-year pot experiment were detected at three levels of soil organic matter and three biochar additions(0,1%and 10%).The difference was found in two biochar application rates.The 1%biochar addition had no positive effect on the soil chemical properties based the two-year experiment.However,10%biochar application significantly increased the soil water content(8.0%-39.7%),the total porosity(9.7%-21.3%),pH(0.26-0.84 unit),organic matter content(89.0%-261.2%),and the available potassium content(29.0%-109.1%).The biomass of soybean increased by 19.4%-78.1%after biochar addition,yet,the soil bulk density reduced at the range of 12.6%-26.0%by 10%biochar addition.Only the 100-grain weight was correlated to the interaction of biochar and the native soil organic matter.All the indicators showed that the interaction between biochar and soil organic matter level was weak in mollisol.The effects of biochar on the physical-chemical properties relied on its amount.When biochar is applied to the soil,the amount of biochar should be considered rather than the native soil organic matter level. 展开更多
关键词 BIOCHAR soil organic matter bulk density available nutrient
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Study on Soil Nutrient Fertility of Cultivated Land in Laos 被引量:1
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作者 Yuyi HUANG Guifen CHEN +7 位作者 Yanfei HUANG Shuyi LIU Yancheng MENG Bin LIU Liping XIE Pheng SENGXUA Moryang CHUAYENG Qizhan TANG 《Agricultural Biotechnology》 CAS 2020年第3期90-92,共3页
[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
关键词 Cultivated land Soil available nutrients nutrient content Laos
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Differences of Soil Nutrient Contents under Different Land Use Patterns in Niyang River Basin
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作者 Heping MA Zhu DONG 《Agricultural Biotechnology》 CAS 2022年第2期80-84,共5页
[Objectives]This study was conducted to investigate the variation characteristics of soil nutrient contents under different land use patterns in the middle and upper reaches of the Niyang River in Tibet.[Methods]With ... [Objectives]This study was conducted to investigate the variation characteristics of soil nutrient contents under different land use patterns in the middle and upper reaches of the Niyang River in Tibet.[Methods]With the cultivated land,grass land and forest land in the middle and upper reaches of the Niyang River as the research objects,216 soil samples were collected in layers(0-10,10-20,20-30 cm)by the standard sampling method,and the soil total nitrogen,alkali-hydrolyzable nitrogen,total potassium,available potassium,total phosphorus,available phosphorus and organic matter were determined.[Results]The contents of soil organic matter,total nitrogen and alkali-hydrolyzable nitrogen in the middle and upper reaches of Niyang River in Tibet ranked as forest land>grass land>cultivated land,and there were significant differences between the three(P<0.05).The total potassium contents of grass land and forest land were not much different,and the contents of available potassium exhibited an order of forest land>grass land>cultivated land.The distribution of soil total nutrients and available nutrients under different land use patterns showed a certain degree of surface aggregation.The contents of total nutrients and available nutrients in the soil at the 0-10 cm depth were significantly higher than those at 10-20 and 20-30 cm,and there were significant differences between the three(P<0.05).The average content of alkali-hydrolyzable nitrogen was the largest in forest soil and the smallest in cultivated land under the three land use patterns in the study area.The average content of soil available phosphorus in cultivated land(19.47 mg/kg)was significantly higher than those in grass land(5.73 mg/kg)and forest land(5.19 mg/kg).The above results indicate that long-term vegetation restoration can improve the soil quality of the middle and upper reaches of the Niyang River.[Conclusions]The results of this study research provide basic support for improving the soil effect in the area. 展开更多
关键词 Soil nutrient Land use type Soil quality available nutrient TIBET
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Effects of Different Oligosaccharides on Performance and Availability of Nutrients in Broilers 被引量:3
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作者 GAOYing SHANAn-shan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2004年第1期37-41,共5页
One hundred and forty-four Avin broilers (1 d of age) were randomly divided into six groups, with three replicates of eight birds each to study on the effects of different oligosaccharides on performance and availabil... One hundred and forty-four Avin broilers (1 d of age) were randomly divided into six groups, with three replicates of eight birds each to study on the effects of different oligosaccharides on performance and availability of nutrients in broilers. The control group(Group I)was fed with corn-soybean meal as basal diet, and the trial groups (Group II, III, IV,V and VI) were fed with basal diet plus 0.1% Manoligosaccharides(MOS), 0.3% Soybean-Oligosaccharides(SBOS), 0.3% Fructo-oligosaccharides(FOS), 0.3% α-Glucooligosaccharides(α-GOS) and 50 mg·L-1 Chlortetracycline(CTC), respectively. The results showed that the supplementation of oligosaccharides slightly improved daily gain and feed intake. SBOS supplementation improved, but MOS and α-GOS significantly decreased availability of energy. Oligosaccharides supplementation improved availability of energy, phosphorus, calcium, magnesium and iron, and significantly increased cholesterol content of fecal, and did not affect on availability of protein and cholesterol contents in serum and muscle. Availability of phosphorus of broilers fed with FOS was much higher than that with α-GOS. SBOS supplementation remarkably increased availability of iron. 展开更多
关键词 OLIGOSACCHARIDES PERFORMANCE availability of nutrients BROILERS
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Arbuscular mycorrhizal fungi improved plant growth and nutrient acquisition of desert ephemeral Plantago minuta under variable soil water conditions 被引量:11
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作者 ZhaoYong SHI Bede MICKAN +1 位作者 Gu FENG YingLong CHEN 《Journal of Arid Land》 SCIE CSCD 2015年第3期414-420,共7页
Desert ephemeral plants play an important role in desert ecosystem.Soil water availability is considered as the major restrictive factor limiting the growth of ephemeral plants.Moreover,arbuscular mycorrhizal fungi(A... Desert ephemeral plants play an important role in desert ecosystem.Soil water availability is considered as the major restrictive factor limiting the growth of ephemeral plants.Moreover,arbuscular mycorrhizal fungi(AM fungi) are widely reported to improve the growth of desert ephemerals.The present study aimed to test the hypothesis of that AM fungi could alleviate drought stress of desert ephemeral Plantago minuta,and AM fungal functions reduced with the improvement of soil water content.A pot experiment was carried out with three levels of soil water contents(4.5%,9.0%,and 15.8%(w/w)),and three AM inoculation treatments(Glomus mosseae,Glomus etunicatum and non-inoculation).The results indicate that mycorrhizal colonization rate decreased with the increase of soil water availability.Inoculation improved plant growth and N,P and K acquisition in both shoots and roots regardless water treatments.When comparing the two fungi,plants inoculated with G.mosseae performed better than those inoculated with G.etunicatum in terms of plant growth and nutrient acquisition.These results showed that ameliorative soil water did not suppress arbuscular mycorrhizal fungal functions in improving growth and nutrient acquisition of desert ephemeral Plantago minuta. 展开更多
关键词 Plantago minuta soil water availability nutrient acquisition desert ephemeral Junggar Basin
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Investigations on the Thermodynamic Stability and Availability of Nutrients for Plants by Humic Substances Extracted from Peat Samples
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作者 Camila De Almeida Melo Lilian Karla De Oliveira Bruno Barboza Cunha Leonardo Femandes Fraceto Andre Henrique Rosa 《Journal of Environmental Science and Engineering(A)》 2015年第7期367-377,共11页
This work evaluated the complexation capacity, exchange constants and availability of micronutrients for plants and humic substances extracted from peat samples. Samples of humic substances extracted from two tropical... This work evaluated the complexation capacity, exchange constants and availability of micronutrients for plants and humic substances extracted from peat samples. Samples of humic substances extracted from two tropical peats (HS-P1 and HS-P2) were enriched with the micronutrients Cu(II), Co(II), Fe(II), Mn(II), Ni(II) and Zn(II) and the parameters for formation of the complexes (HS-N) were evaluated at different pH. The Scatchard model was used to calculate the maximum complexation capacity and the nutrient availability was studied using exchange capacity experiments based on ultrafiltration procedure. The optimum pH for complexation was 4.5 and the order of affinity was: Fe(II) 〉 Cu(II) 〉 Co(II) 〉 Mn(II) = Ni(II) 〉 Zn(II). The maximum complexation capacity reached 56.8 mg·g-1 Fe of HS-P1 (the highest) and 1.7 mg.g1 Zn of HS-P2 (the slightest). The exchange experiments showed that HS-P-Fe complexes were formed preferentially. The least stable complex was formed with Zn, which was therefore, more easily available. The results contribute to understand the behavior and availability of some nutrients in soils. 展开更多
关键词 Peat humic substances COMPLEXATION nutrient availability exchange capacity soil
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Using vibrational infrared biomolecular spectroscopy to detect heat-induced changes of molecular structure in relation to nutrient availability of prairie whole oat grains on a molecular basis
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作者 M. D. Mostafizar Rahman Katerina Theodoridou Peiqiang Yu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2017年第1期128-133,共6页
Background: To our knowledge, there is little study on the interaction between nutrient availability and molecular structure changes induced by different processing methods in dairy cattle. The objective of this stud... Background: To our knowledge, there is little study on the interaction between nutrient availability and molecular structure changes induced by different processing methods in dairy cattle. The objective of this study was to investigate the effect of heat processing methods on interaction between nutrient availability and molecular structure in terms of functional groups that are related to protein and starch inherent structure of oat grains with two continued years and three replication of each year.Method: The oat grains were kept as raw(control) or heated in an air-draft oven(dry roasting: DO) at 120 °C for 60 min and under microwave irradiation(MIO) for 6 min. The molecular structure features were revealed by vibrational infrared molecular spectroscopy.Results: The results showed that rumen degradability of dry matter, protein and starch was significantly lower(P 〈0.05) for MIO compared to control and DO treatments. A higher protein α-helix to β-sheet and a lower amide I to starch area ratio were observed for MIO compared to DO and/or raw treatment. A negative correlation(-0.99, P 〈 0.01)was observed between α-helix or amide I to starch area ratio and dry matter. A positive correlation(0.99, P 〈 0.01) was found between protein β-sheet and crude protein.Conclusion: The results reveal that oat grains are more sensitive to microwave irradiation than dry heating in terms of protein and starch molecular profile and nutrient availability in ruminants. 展开更多
关键词 Dry roasting Feed processing Microwave irradiation Modeled cereal grains Molecular structure nutrient availability
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Decomposition and Mineralization Effect of Various Sources of Pig Manure on Water Quality and Nutrients Availability for Agro-Fish System in Benin
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作者 H.K.J.Bokossa A.Saidou +2 位作者 E.Sossoukpe D.E.Fiogbe D.Kossou 《Agricultural Sciences》 2014年第12期1194-1206,共13页
In spite of the relevance of current studies on the importance of organic fertilizers such as animal manure in improving the health of ecosystems, little is known about the biochemical mechanisms affecting the availab... In spite of the relevance of current studies on the importance of organic fertilizers such as animal manure in improving the health of ecosystems, little is known about the biochemical mechanisms affecting the availability of nutrients released from the organic fertilizer in water. A litter bag study during 6 weeks was carried out in pots containing 25 liters of water with 15 g of pig dejections as organic fertilizers. The experimental design was a completely randomized block design with three replications. The treatments consisted of dejections of pigs nourished with: recommended diet composition T1, partially improved diet with Azolla filiculoides T2, improved diet with Azolla filiculoides T3, improved diet with cereal bran T4. A control treatment without dejection (T0) was considered in the study for comparison purpose. Four pigs per type of diet were considered leading to 16 white landrace pigs of six months age followed for dejection collections. Strong release of nutrients for better yield for agro-fish system was obtained in the manure T1 with ??(10.85 ± 0.00) mg/L;?( 0.011 ± 0.00) mg/L;?(2.13 ± 0.07) mg/L and K+ (10.76 ± 0.57) mg/L;Ca2+ (2.92 ± 0.11) mg/L and Mg2+ (2.53 ± 0.00) mg/L followed by manure T3 and T4 with high N content. The relatively low ratio C/N (14.25) for T1 and (15.84) for T3 induced more nutrients releasing. This study showed an important N loss probably due to microorganism activities which fluctuate nutrient availability. Also significant correlations were noted between the nutrient dynamics in water and physicochemical parameters showing the effect of abiotic factors on organic matter decomposition and mineralization which depend on microbial activities in water and pig manure composition. 展开更多
关键词 Pig’s Diet MANURE FERTILIZATION Physico-Chemical Microbial Water Properties nutrients Availability
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Analysis of Soil Degradation Causes in Orchards with Different Planting Years 被引量:4
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作者 王治国 付彦博 +3 位作者 饶晓娟 耿庆龙 孟阿静 冯耀祖 《Agricultural Science & Technology》 CAS 2014年第8期1331-1334,共4页
The aim was to analyze effects of jujube planting years on changes of soil nutrient elements and explore the causes of orchard degradation by researching variation characteristics of soil nutrient contents in orchards... The aim was to analyze effects of jujube planting years on changes of soil nutrient elements and explore the causes of orchard degradation by researching variation characteristics of soil nutrient contents in orchards with different planting years, providing theoretical support for the soil degradation of jujube or-chards. [Method] Soil samples were col ected in depth at 0-20 and 20-40 cm from the sites in or out of tree canopy scope in jujube orchards with 3, 5 and 7 plan-ning-years, to analyze contents of available N, P and K, organic matter, total N, salts, and trace elements, as wel as changes of nutritional elements. [Result] Avail-able boron, copper, iron, manganese, zinc and available potassium in soils of jujube orchards with 3, 5 and 7 years planting history reduced as planting year increased, which coincided with that in the soil of 20-40 cm. [Conclusion] Because trace ele-ments are never applied in southern Xinjiang, available B, Cu, Fe, Mn, and Zn and available K would be consumed by tree root growth. Due to root distribution differ-ences and ploughing effects in fields, the contents of nutrients tend to be volatile in or out of tree canopy scope. Tree root in deeper soils absorbs more nutrients, and soil nutrients would decrease dramatical y if additional chemical fertilizers are not provided, leading to soil degradation. 展开更多
关键词 ORCHARD Soil degradation Soil available nutrient Trace element in soil
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A review of the effects of forest fire on soil properties 被引量:7
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作者 Alex Amerh Agbeshie Simon Abugre +1 位作者 Thomas Atta-Darkwa Richard Awuah 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第5期1419-1441,共23页
Forest fires are key ecosystem modifiers affecting the biological,chemical,and physical attributes of forest soils.The extent of soil disturbance by fire is largely dependent on fire intensity,duration and recurrence,... Forest fires are key ecosystem modifiers affecting the biological,chemical,and physical attributes of forest soils.The extent of soil disturbance by fire is largely dependent on fire intensity,duration and recurrence,fuel load,and soil characteristics.The impact on soil properties is intricate,yielding different results based on these factors.This paper reviews research investigating the effects of wildfire and prescribed fire on the biological and physico-chemical attributes of forest soils and provides a summary of current knowledge associated with the benefits and disadvantages of such fires.Low-intensity fires with ash deposition on soil surfaces cause changes in soil chemistry,including increase in available nutrients and pH.High intensity fires are noted for the complete combustion of organic matter and result in severe negative impacts on forest soils.High intensity fires result in nutrient volatilization,the break down in soil aggregate stability,an increase soil bulk density,an increase in the hydrophobicity of soil particles leading to decreased water infiltration with increased erosion and destroy soil biota.High soil heating(> 120℃) from high-intensity forest fires is detrimental to the soil ecosystem,especially its physical and biological properties.In this regard,the use of prescribed burning as a management tool to reduce the fuel load is highly recommended due to its low intensity and limited soil heating.Furthermore,the use of prescribed fires to manage fuel loads is critically needed in the light of current global warming as it will help prevent increased wildfire incidences.This review provides information on the impact of forest fires on soil properties,a key feature in the maintenance of healthy ecosystems.In addition,the review should prompt comprehensive soil and forest management regimes to limit soil disturbance and restore fire-disturbed soil ecosystems. 展开更多
关键词 Forest fires Low-severity fire MINERALIZATION Soil available nutrients Soil organic matter VOLATILIZATION
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Soil pH Dynamics and Nitrogen Transformations Under Long-Term Chemical Fertilization in Four Typical Chinese Croplands 被引量:7
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作者 MENG Hong-qi XU Ming-gang +6 位作者 L Jia-long HE Xin-hua LI Jian-wei SHI Xiao-jun PENG Chang WANG Bo-ren ZHANG Hui-min 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第11期2092-2102,共11页
Long-term fertilization experiment provides the platform for understanding the proton budgets in nitrogen transformations of agricultural ecosystems. We analyzed the historical (1990-2005) observations on four agric... Long-term fertilization experiment provides the platform for understanding the proton budgets in nitrogen transformations of agricultural ecosystems. We analyzed the historical (1990-2005) observations on four agricultural long-term experiments in China (Changping, Chongqing, Gongzhuling and Qiyang) under four different fertilizations, i.e., no-fertilizer (control), sole chemical nitrogen fertilizer (FN), sole chemical phosphorous and potassium fertilizers (FPK) and chemical nitrogen, phosphorous and potassium fertilizers (FNPK). The significant decline in topsoil pH was caused not only by chemical N fertilization (0.29 and 0.89?pH at Gongzhuling and Qiyang, respectively) but also by chemical PK fertilization (0.59?pH at Gongzhuling). The enhancement of available nutrients in the topsoil due to long-term direct nutrients supply with chemical fertilizers was in the descending order of available P (168-599%)〉available K (16-189%)〉available N (9-33%). The relative rate of soil pH decline was lower under long-term judicious chemical fertilization (-0.036-0.034 ?pH yr-1) than that under long-term sole N or PK fertilization (0.016-0.086 ?pH yr-1). Long-term judicious chemical fertilization with N, P and K elements decreases the nutritional limitation to normal crop growth, under which more N output was distributed in biomass removal rather than the loss via nitrate leaching. We concluded that the N distribution percentage of nitrate leaching to biomass removal might be a suitable indicator to the sensitivity of agricultural ecosystems to acid inputs. 展开更多
关键词 available nutrients ECOSYSTEM long-term fertilization N distribution soil pH
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Impact of Continuous Chinese Fir Monoculture on Soil 被引量:13
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作者 YANGYu-Sheng LIUChun-Jiang: +2 位作者 W.KUTSCH CHENGuang-Shuit YUXin-Tuo 《Pedosphere》 SCIE CAS CSCD 2004年第1期117-124,共8页
Soil properties were investigated in sites where three succeeding generationsof Chinese fir (Gunning-hamia lanceolata, (Lambert) Hooker) in Nanping, Fujian, China, werecultivated in order to show the impact of a repea... Soil properties were investigated in sites where three succeeding generationsof Chinese fir (Gunning-hamia lanceolata, (Lambert) Hooker) in Nanping, Fujian, China, werecultivated in order to show the impact of a repeated monoculture on site productivity. Compared withthe first generation (FG) stand the soil structure deteriorated in the second generation (SG) andthe third generation (TG) stands. For instance, the destruction rate of the peds increased by 55%-115% in the SG and the TG stands compared to the FG stand. Soil nutrient storage and nutrientavailability also decreased in the SG and the TG stands. For surface soils of 0-20 cm, the organicmatter content, total N and P, and available N and P decreased by 3%-20% relative to those in the FGstand. For many soil parameters, the differences between the FG stand and the SG and the TG standswere statistically significant (LSD test, P < 0.05). Furthermore, with each succeeding generation ofChinese fir, the total number of soil microbes declined, the soil enzyme activity weakened, and thesoil biological activity decreased. In order to maintain sustainable site productivity, newsilvicultural practices need to be developed for management of Chinese fir plantations. 展开更多
关键词 chinese fir nutrient availability repeated monoculture soil biochemistry soil structure
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N and P resorption in a pioneer shrub(Artemisia halodendron) inhabiting severely desertified lands of Northern China 被引量:11
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作者 YuLin LI Chen JING +3 位作者 Wei MAO Duo CUI XinYuan WANG XueYong ZHAO 《Journal of Arid Land》 SCIE CSCD 2014年第2期174-185,共12页
Nutrient resorption is an important conservation mechanism for plants to overcome nutrient limitation in the less fertile area of desertifled land. In the semi-arid Horqin Sandy Land of Northern China, the shrub Artem... Nutrient resorption is an important conservation mechanism for plants to overcome nutrient limitation in the less fertile area of desertifled land. In the semi-arid Horqin Sandy Land of Northern China, the shrub Artemisia ha/odendron usually colonizes into the bare ground of severely desertified land as a pioneer species. It is, therefore, expected that A. ha/odendron will be less dependent on current nutrient uptake through efficient and proficient re- sorption of nutrients. In this study, we found that averaged nitrogen (N) and phosphorus (P) concentrations in se- nesced leaves significantly varied from 12.3 and 1.2 mg/g in the shifting sand dune to 15.9 and 1.9 mg/g in the fixed sand dune, respectively, suggesting that foliar N and P resorption of A. ha/odendron were more proficient in the shifting sand dune. In particular, positive relationships between nutrient concentrations in senesced leaves and soil nutrient availability indicate that A. ha/odendron in infertile habitats is more likely to manage with a low level of nu- trients in senesced leaves, giving this species an advantage in infertile soil. Moreover, foliar N- and P-resorption efficiencies and proficiencies showed limited inter-annual variability although annual precipitation varied greatly among 2007-2009. However, N and P resorption of A. ha/oc/endron were not more efficient and proficient than those previously reported for other shrubs, indicating that the pioneer shrub in sand dune environments does not rely more heavily than other plants on the process of resorption to conserve nutrients. Incomplete resorption of nutrients in A. halodendron suggests that senesced-leaf fall would return litter with high quality to the soil, and thereby would indirectly improve soil nutrient availability. The restoration of desertified land, therefore, may be ac- celerated after A. halodendron pioneers into shifting sand dunes. 展开更多
关键词 foliar nutrient concentration nutrient-resorption efficiency nutrient-resorption proficiency senesced vs. green leaves DESERTIFICATION soil nutrient availability
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Variation of soil enzyme activity and microbial biomass in poplar plantations of different genotypes and stem spacings 被引量:6
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作者 Ye Li Liping Zhang +2 位作者 Shengzuo Fang Ye Tian Jiao Guo 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第4期958-967,共10页
To improve the productivity of poplar planta- tions, a field experiment of split-plot design with four tree spacings and three poplar clones was established, and four soil enzyme activities and microbial biomass were ... To improve the productivity of poplar planta- tions, a field experiment of split-plot design with four tree spacings and three poplar clones was established, and four soil enzyme activities and microbial biomass were monitored in the trial. Soil enzyme activities, in most cases, were significantly higher in topsoil (0-10 cm) than in lower horizons (10-20 cm). Soil cellulase, catalase and protease activities during the growing season were higher than during the non-growing season, while invertase activity followed the opposite trend. Soil invertase, cellulase and catalase activities varied by poplar clone but soil protease activity did not. Cellulase and protease activities in the plantation at 5 × 5 m spacing were significantly higher than in the other spacings. The highest catalase activity was recorded at 6 × 6 m spacing. At the same planting density, invertase activity was greater in square spacings than in rectangular spacings. Soil microbial biomass was also significantly affected by seedling spacing and poplar clone. The mean soil MBC was significantly lower in topsoil than in the lower horizon, while MBN showed the opposite pattern. Significantly positive correlations were observed among soil cellulase, protease and catalase activities (p 〈0.01), whereas soil invertase activity was negatively and significantly correlated with cellulase, protease and catalase activities (p 〈 0.01). Soil microbial biomass and enzyme activities were not correlated except for a significantly negative correlation between soil MBC and catalase activities. Variations in soil enzyme activity and microbial biomass in different poplar plantations suggest that genotype and planting spacing should be considered when modeling soil nutrient dynamics and managing for long-term site productivity. 展开更多
关键词 Microbial activity nutrient availability Planting density Poplar clone Seasonal variation
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Antioxidant compounds and minerals in tomatoes by Trichodermaenriched biofertilizer and their relationship with the soil environments 被引量:4
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作者 Yeakub Khan Manjurul Haque +2 位作者 Abul Hossain Molla Mizanur Rahman Mohammad Zahangeer Alam 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第3期691-703,共13页
The experiment was conducted to evaluate the efficacy of Trichoderma-enriched biofertilizer(BioF/compost)on antioxidants and minerals in ripe tomatoes and soil health improvements in terms of nutrient availability a... The experiment was conducted to evaluate the efficacy of Trichoderma-enriched biofertilizer(BioF/compost)on antioxidants and minerals in ripe tomatoes and soil health improvements in terms of nutrient availability and microbial populations.The study was comprised of six treatments:control(zero input);recommended doses of NPK(135.5,45.6 and 22.9 kg ha^-1,respectively);100%BioF/compost;75%BioF/compost+25%N;50%BioF/compost+50%N;and 25%BioF/compost+75%N.The recommended doses of P and K were used in the last three treatments.It was found that the application of 100%BioF/compost enhanced plant growth,leaf greenness,and produced 12.9%higher yield compared to the recommended doses of NPK and other treatments.Mineral contents(P,K,Ca,Mg,Cu,Fe,Mn and Zn)in tomato roots,shoots and fruits and antioxidant compounds,i.e.,ascorbic acid,β-carotine,and lycopene were increased significantly in fruits fertilized with100%BioF/compost.The high efficiency of Trichoderma compost might be the result of its potential of nutrient solubilization and harboring soil microorganisms.Collectively,BioF/compost increased soil fertility and favored growth of microbes in the rhizosphere which ultimately contributed to higher yield,antioxidant,and mineral concentrations in tomatoes.Thus,Trichoderma-enriched biofertilizer may reduce application of chemical fertilizers and therefore,can be considered as a noble practice in sustainable agriculture. 展开更多
关键词 Trichoderma harzianum T22 MINERALS .antioxidants nutrient availability microbial populations
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A Study of Soil-dynamics Based on a Simulated Drought in an Alpine Meadow on the Tibetan Plateau 被引量:4
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作者 WANG Zhi-yuan SUN Geng +2 位作者 LUO Peng MOU Cheng-xiang WANG Jun 《Journal of Mountain Science》 SCIE CSCD 2013年第5期833-844,共12页
Extreme weather events have played an important role in driving the ecosystem dynamics in high altitude areas, but the underlying mechanism remains unclear. To understand if and how the soil processes of an ecosystem ... Extreme weather events have played an important role in driving the ecosystem dynamics in high altitude areas, but the underlying mechanism remains unclear. To understand if and how the soil processes of an ecosystem react to extreme drought, we manipulated a once-in-a-century meteorological extreme drought in an alpine meadow on the Tibetan Plateau, which is also known as the "forerunner of global weather changes". The extremity was determined by statistical extreme weather events with respect to a historical reference period from April to September during 1962 - 2004, where the local historical precipitation data was calculated and intensified to loo-year recurrent drought event with Gumbel I distribution. The indicators we measured included soil microbial biomass C/N/P and soil enzymatic activities of phosphatase (AP) disbounding organic phosphate, cellobiohydrolase (CBH), β- glucocidase (BG), N-releasing enzyme N-acetyl- glucosaminidase (NAG) as well as soil respirations, during and after the treatments. It was found that the manipulated event induced a rapid shift in microbial biomass and activities, indicating a lower resistance of the underground process. However, the microbial and biochemical parameters saw rapid recovery after the event, which meant the soil processes enjoyed high resilience. The high responsiveness and lag-time effects of the soil indicators rendered new horizons for us to evaluate the interaction between the extremes and the ecosystem stability. Our study indicated that the once-in-a-century extreme drought induced very short term response in the soil biotic process, and the soil processes worked to buffer against such events under the observation period. 展开更多
关键词 Extreme weather event Soil enzyme Microbial biomass nutrient availability
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Growth characteristics of multipurpose tree species, crop productivity and soil properties in agroforestry systems under subtropical humid climate in India 被引量:3
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作者 M. Datta N. P. Singh 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第4期261-270,共10页
Multipurpose tree species (MPTs) were studied in an agroforestry arboretum under subtropical humid climate in Northeast India. Out of 12 MPTs planted under agroforestry systems, Acacia auriculiformis in spacing of 2... Multipurpose tree species (MPTs) were studied in an agroforestry arboretum under subtropical humid climate in Northeast India. Out of 12 MPTs planted under agroforestry systems, Acacia auriculiformis in spacing of 2 m × 2 m (2500 stems·hm^-2) could have the potentiality to meet the timber/fuelwood requirement due to its high wood production of 635 m^3·hm^-2 with mean annual increment (MAI) of 2.54×10^-2 m^3.treel.a^-1 in a short rotation period of 10 years. Thus, A. auriculiformis is a short rotation forest tree species suitable to grow in subtropical humid climate. On the other hand, at 16 years of age, Eucalyptus hybrid and Michelia champaca in spacing of 3 m × 3 m (1111 stems.hm^2) produced appreciably high timber volume of 315 m^3.hm^-2 and 165 m^3.hm^-2 with MAI of 1.77×10^-2 m^3.tree^-1·a^-1 and 0.92×10.2 m^3.tree^-1.a^-1, respectively. At 16 years of age, Gmelina arborea produced a timber volume of 147 m^3.hm^-2 with MAI of 1.47×10^-2 m^3.tree^-1.a^-1 followed by Samania saman (140 m^3.hm^-2), Albizziaprocera (113 m^3·hm^-2) and Tectona grandis (79 m3.hm^-2) with MAI of 1.40, 1.13 and 0.78 × 10^-2 m^3 .tree^-1a^-1, respectively in 4 m × 4 m spacing (625 stems.hm^-2). Gliricidia maculata and Leucaena leucocephala could be used as live fences around the farm boundary to supply their N-rich leaves for mulch as well as manure to crops. In agroforestry arboretum, direct seeded upland rice (Oryza sativa - variety, AR-11), groundnut (Arachis hypogaea - variety, JL-24) and sesamum (Sesamum indicum - variety, B-67) were grown during the initial period upto 8 years of tree establishment. Under other MPTs, there was a reduction in crop productivity as compared to open space. After 8 years of tree establishment, horti-silvi and silvi-pastoral systems were developed and pineapple (Ananas comosus - variety Queen), turmeric (Curcuma longa -variety RCT -1) and cowpea (Vigna sinensis - variety Pusa Barsati) as forage crop were raised. The productivity of pineapple, turmeric and cowpea was comparatively high under Azadirachta indica. The productivity of horticultural and forage crops in association with trees such as G. arborea, A. procera, S. saman, T. grandis and M. champaca of high timber value could be harnessed as viable agroforestry systems. Changes in soil properties were also monitored. Amelioration of soil acidity, increase in soil organic carbon, and enhanced humification of soil humus, high nutrient availability, low soil erodibility and high surface soil (0-15 cm) moisture availability were noted in soils under MPTs. 展开更多
关键词 Multipurpose trees Subtropical humid climate Growth characteristics Timber volume Crop productivity Soil organic car-bon Soil humus nutrient availability Soil erodibility indices Soil moisture.
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Board-invited review: Sensitivity and responses of functional groups to feed processing methods on a molecular basis 被引量:2
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作者 Peiqiang Yu 《Journal of Animal Science and Biotechnology》 SCIE CAS 2013年第1期1-4,共4页
In complex feed structures, there exist main chemical functional groups which are associated with nutrient utilization and availability and functionality. Each functional group has unique molecular structure therefore... In complex feed structures, there exist main chemical functional groups which are associated with nutrient utilization and availability and functionality. Each functional group has unique molecular structure therefore produce unique molecular vibration spectral profile. Feed processing has been used to improve nutrient utilization for many years. However, to date, there was little study on processing-induced changes of feed intrinsic structure and functional groups on a molecular basis within intact tissue. This is because limited research technique is available to study inherent structure on a molecular basis. Recently bioanalytical techniques: such as Synchrotron Infrared Microspectroscopy as well as Diffuse Reflectance Infrared Fourier Transform molecular spectroscopy have been developed. These techniques enable to detect molecular structure change within intact tissues. These techniques can prevent destruction or alteration of the intrinsic protein structures during processing for analysis. However, these techniques have not been used in animal feed and nutrition research. The objective of this review was show that with the advanced technique, sensitivity and responses of functional groups to feed processing on a molecular basis could be detected in my research team. These functional groups are highly associated with nutrient utilization in animals. 展开更多
关键词 Sensitivity and responses of functional groups Molecular structures Feed processing nutrient utilizationand availability
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Impact of MgCl<sub>2</sub>Modified Biochar on Phosphorus and Nitrogen Fractions in Coastal Saline Soil 被引量:1
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作者 Sharmin Jannat Lutfunnahar Mahmudul Islam Piash M. Hasinur Rahman 《Open Journal of Soil Science》 2021年第6期331-351,共21页
Biochar application is claimed to improve nutrient availability in many problem soils;however, pristine biochars are often reported to produce inconsistent results. Therefore, appropriate biochar modification techniqu... Biochar application is claimed to improve nutrient availability in many problem soils;however, pristine biochars are often reported to produce inconsistent results. Therefore, appropriate biochar modification techniques are required to retain soil nutrients at an optimum level. To increase Nitrogen (N) and Phosphorus (P) availability in coastal saline soil, two slow pyrolyzed biochars viz domestic organic waste (DWB) and farmyard manure (FMB) were modified with MgCl<sub>2</sub>. Ten different treatments comprising the biochars (pristine and modified) with and without the recommended fertilizer were applied (2% w/w) to the soil and incubated for ninety days. The soils were analyzed for pH, EC, available <img src="Edit_0d6ce0cb-4936-4874-a480-35d5b2f585ff.png" alt="" />, <img src="Edit_64cd5bd3-ddeb-4e08-ad2e-48f0710feace.png" alt="" /> and different phosphorus fractions sequentially extracted by NH<sub>4</sub>Cl, NaHCO<sub>3</sub>, NaOH, and HCl. During the incubation period, biochar treatments increased all phosphorus and nitrogen fractions than the control and recommended fertilizer treatment. The application of FMB significantly (<em>p</em> < 0.05) increased NH<sub>4</sub>Cl, NaHCO<sub>3</sub>, and NaOH extractable P fractions from DWB, while HCl soluble fraction was enhanced (<em>p</em> > 0.05) by DWB. The increased Al and/or Fe bound phosphate after 60 days of incubation had significant correlations to decreasing soil pH and NaHCO<sub>3</sub>-P, indicating reduced availability with time. Further Mg modification slightly increased P availability only after 60 days of incubation. The modification also improved both nitrogen fractions but significantly (<em>p</em> < 0.05) increased the NO<sub>3</sub>-N content which could be the result of electrostatic attraction between Mg<sup>2</sup>+ and <img src="Edit_c55861ac-dd25-4c26-9ecc-2e134a948b8e.png" alt="" /> ions. Overall, Mg-modified biochar may retain both phosphates and nitrates in soil. However, the magnitude of retention will vary depending on biochar type, nutrient species, and aging in soil. 展开更多
关键词 Biochar Application Saline Soil MgCl2 Modification nutrient Availability PHOSPHORUS
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