[ Objective] To explore the effects of different proportion of bee pollen on the water holding capacity of pork in Duroc Landrace x Yorkshire growing-finishing pigs in order to determine the optimal proportion. [ Met...[ Objective] To explore the effects of different proportion of bee pollen on the water holding capacity of pork in Duroc Landrace x Yorkshire growing-finishing pigs in order to determine the optimal proportion. [ Method] A total of 80 Duroc x Landrace x Yorkshire growing-finishing pigs, weighing (10.0 ± 1.0) kg, were randomly divided into five groups. The experimental period was 120 d including the 5-day pre-feecling period. The corn-soybean meal was not replaced during the whole period. All pigs had free access to feed and water. The pigs were fasting for 24 h but not prohibited from feed before the beginning. Group I was the control group reared with the diet not supplemented bee pollen. The pigs in group II, III ,IV and V were reared with the diet supplemented bee pollen at the concentration of 1%, 3%, 5% and 7%, respectively. After slaughtering, eye muscle was used for determination of water holding capacity through fast filter paper method, drip loss method, cooking loss method and Na- pole yield determination method. [ Resultl With the increase of the proportion of bee pollen, the water holding capacity of pork was first good and then poor. The addition of bee pollen at the concentration of 5% significantly reduced the drip loss of pork and the water holding capacity which was detected by fast filter paper method, but the cooking loss and Napole yield were not significantly influenced. [ Condmion] The bee pollen can effectively improve the water holding capacity of pork in Duroc x Landrace x Yorkshire growing-finishing pigs, and the optimal proportion is 5%.展开更多
Rapid expansion of cultivated bamboo negatively impacts on biodiversity and soil microbial community.As such,it is important to properly manage and use bamboo to prevent and control such issues.This study focuses on o...Rapid expansion of cultivated bamboo negatively impacts on biodiversity and soil microbial community.As such,it is important to properly manage and use bamboo to prevent and control such issues.This study focuses on optimizing pyrolysis conditions to produce bamboo biochar for agricultural soil amendment,particularly soil potassium(K)and water holding capacity.Bamboo chips were pyrolyzed under nitrogen gas at 400,600,and 800℃ for 1 and 2 h of retention.A total of six biochar products were created:400-1(i.e.,400℃ in 1 h),400-2,600-1,600-2,800-1,and 800-2.The 600℃ bamboo biochar products were observed to have the greatest potential in increasing soil K and water holding capacity.The 600-1 product had the highest potassium content(4.87%),with a water holding capacity of 3.73 g g^(−1),while the 600-2 product had the second-highest potassium content(4.13%)and the highest water holding capacity(4.21 g g^(−1))and cation exchange capacity.The K release in 600℃ products was larger and slower than that of the 400℃ and 800℃ products,respectively.The results also indicated that the physicochemical characteristics of bamboo biochar,such as yield,pH,surface area,water holding capacity,and K content,were significantly impacted by temperature,retention time,or a combination of these parameters.The outcomes from this study are a valuable reference for bamboo biochar production targeting agricultural soil amendment,particularly when it is directed at increasing soil K and water holding capacity.展开更多
The current study was carried out to detect the effect of dietary guanidinoacetic acid(GAA)supplementation on carcass characteristics and meat quality in finishing pigs fed different dietary crude protein(CP)levels.Si...The current study was carried out to detect the effect of dietary guanidinoacetic acid(GAA)supplementation on carcass characteristics and meat quality in finishing pigs fed different dietary crude protein(CP)levels.Sixty-four barrows with an initial body weight of 73.05±2.34 kg were randomly allocated into 1 of 4 dietary treatments in a 2(100%vs.125%NRC CP level)×2(0 vs.300 mg/kg GAA)factorial arrangement(n=7).The feeding trial lasted for 49 d.GAA supplementation significantly reduced drip loss(P=0.01),free water distribution(T23peak area ratio)(P=0.05)and the concentrations of free alanine,threonine,methionine and isoleucine(P<0.05);but increased total glycine content(P=0.03)in the longissimus dorsi muscle of finishing pigs regardless of the dietary CP levels.Furthermore,primary myogenic cell differentiation system was employed to investigate the influence of inclusion of GAA on free amino acid concentrations in myotubes(n=4)and validate the finding in the animal feeding trial.We found that GAA inclusion in culture medium also decreased intracellular concentrations of free alanine,threonine,methionine,isoleucine,valine and proline in differentiated primary myogenic cells in vitro(P<0.05).Meanwhile,relative to diets with 100%NRC CP level,the intake of diets with 125%NRC CP level improved sarcoplasmic protein solubility,increased the contents of carnosine and total free amino acids as well as flavor amino acids in the longissimus dorsi muscle and decreased backfat thickness at the 6-7th ribs in pigs(P<0.05).In addition,we observed that the impact of dietary GAA supplementation on the last rib fat thickness,shear force,and free lysine content in the longissimus dorsi muscle was dependent on dietary CP levels(P<0.05).Collectively,dietary GAA supplementation can reduce drip loss,decrease the concentrations of free amino acids and flavor amino acids of fresh meat independent of dietary CP levels.展开更多
Relationship of soil and water is generally considered as important in soil science. To specify it further we studied two different soils in 2012-2013, three additional soils once and made several series of experiment...Relationship of soil and water is generally considered as important in soil science. To specify it further we studied two different soils in 2012-2013, three additional soils once and made several series of experiments with drying and wetting of the soils. Principal parameters studied were the gravimetric water content (GWC), water holding capacity (WHC), soil organic matter (SOM), their correlations and rates of change in drying or wetting. The three parameters are significantly inter-correlated. Distribution of GWC in the replicates of soils dried both in nature and in experiments was narrower than that in wet soils, while WHC changed less in drying. The correlations (GWC- WHC) became steeper (the slope coefficient higher) and the coefficient of determination (R2) lower. Attempts to increase WHC in wet soils with a high WHC even further were not successful. Drying may be fast or slow;rates of increase of WHC in wetting were all low, both in field and in the experiments, less than 0.1 g (H2O) g-1 (soil)·day-1. None of the three parameters can be considered as fixed characteristics of forest soils.展开更多
[Objective] This study was to reveal the effect of different land use patterns on physical characteristics of soil water in the Yellow River wetland in Shaanxi Province.[Method]Taking Yellow River wetland in Shaanxi P...[Objective] This study was to reveal the effect of different land use patterns on physical characteristics of soil water in the Yellow River wetland in Shaanxi Province.[Method]Taking Yellow River wetland in Shaanxi Province as experimental plot,we compared the physical properties of the soil water under different land use patterns and studied the physical properties and the change law of soil water during the wetland degeneration process.[Result]Under different land use patterns,soil bulk density rose with the increase of soil depth.During the degeneration process of from river wetland to reclaimed wetland(paddy field),finally to abandoned land owing to salinization,the mean soil bulk density reduced correspondingly from 1.474 to 1.522 g/cm3,finally to 1.593 g/cm3 when abandoned.Accompanying wetland degeneration,soil became compact increasingly,and the indicators of soil porosity(total porosity,capillary porosity,non-capillary porosity)were also reduced with the change of land use patterns,in which,capillary porosity and total porosity reached the extremely significant level with the change of land use patterns,and non-capillary porosity reached significant level.The changes of soil porosity condition accelerated the deterioration of wetland.Under different land use patterns,the maximum soil moisture capacity,capillary moisture capacity and minimum moisture capacity all showed a similar change law.Compared with wetland,the maximum soil moisture capacity of reclaimed land(paddy field)and salinized land respectively decreased by 5.7% and 22.3%,capillary moisture capacity by 0.2% and 19.4%,minimum moisture capacity by 2.7% and 15.9%.Of the three land use patterns,wetland displayed both higher water holding capacity and water drainage capacity over reclaimed land(paddy field)and salinized land.By comparison with wetland,the reclaimed land(paddy field)and salinized land respectively decreased by 12.4% and 15.2% in total water holding capacity,and by 2.7% and 15.9% in total water drainage capacity.[Conclusion]To conserve the water resource in Yellow River wetland,regulate the hydrological cycle and enhance drought and water logging resistances,it should be noted that reasonable countermeasures be taken to exploit the state-owned forest land and paddy field around the wetland and the related resources.展开更多
[Objective]The aim of this study was to select tartary buckwheat material with better health function.[Method]Used 35 kinds of tartary buckwheat as experimental materials,and the water holding capacity and expansion c...[Objective]The aim of this study was to select tartary buckwheat material with better health function.[Method]Used 35 kinds of tartary buckwheat as experimental materials,and the water holding capacity and expansion capacity had been determined.[Result] The water holding capacity of 35 kinds of tartary buckwheat will change in the range of 248.5%-341.4% with an average of 283.0%(the holding capacity of T324 was the highest),while the change of expansion capacity changed between 0.50 and 1.50 ml/g with an average of 1.05 ml/g(the expansion capacity of T463 was the highest).[Conclusion]This study had provided theoretical basis for screening better tartary buckwheat variety and its application.展开更多
Although forests play important roles in the hydrological cycle,there is little information that relates the water retention capacity of litter in areas under passive restoration,especially in Cerrado savannas.This st...Although forests play important roles in the hydrological cycle,there is little information that relates the water retention capacity of litter in areas under passive restoration,especially in Cerrado savannas.This study relates litter levels to water holding capacity and effective water retention among forest fragments under different passive restoration stages:46,11,and 8 years to better understand litter hydrological functions in the Cerrado.Water retention capacity and effective water retention capacity of litters(unstructured materials,branches and leaves)in the field were monitored on a monthly basis.Total litter accumulation at 46 years was significantly higher than that of the other succession stages.Unstructured litter mass was significantly higher than that of leaves and branches.The 46-year stage had the highest water holding capacity in the leaf fraction,followed by unstructured material and branches.Although the water holding capacity was lower in the oldest resto-ration,this site showed the highest efficiency under field conditions.The process was quickly reestablished,as the 11-year restoration showed results closer to that for the 46-year stage in comparison to the area at 8 years.Thus,passive restoration plays a key role in soil water mainte-nance due to the influence of litter in Cerrado savannas.Deforestation and the imminent need of restoring degraded sites,highlight the need for further studies focused on bet-ter understanding of the process of forest restoration and its temporal effect on soil water recovery dynamics.展开更多
After water imbibition, the outer layer seed coat of shaddock (Citrus grandis Osbeck) produces transparent gel-like mucilage (MSS), but its characteristics have never been studied before. This study aimed to assess th...After water imbibition, the outer layer seed coat of shaddock (Citrus grandis Osbeck) produces transparent gel-like mucilage (MSS), but its characteristics have never been studied before. This study aimed to assess the physico-chemical and functional properties of MSS. Extractions of MSS with deionized water at room temperature yielded about 3.5% based on the dry weight of seed. The major components were neutral sugars and uronic acids in the amounts of 33.5% and 49.6%, respectively. The acidic nature of MSS was confirmed by ruthenium red staining. Its water holding capacity and viscosity were 44.53 g•g<sup>-1</sup> DW and 1660 cP at 10 g/L, respectively. MSS showed a weak quenching activity against DPPH radical, and moderate ferrous ion-chelating and superoxide anion radical scavenging activities, with IC<sub>50</sub> value of 1.5 g/L and 1.1 g/L, respectively. A methyl thiazolyl tetrazolium (MTT) assay demonstrated that MSS significantly stimulated the viability of mouse skin fibroblasts (NIH/3T3) at 5 - 300 mg/L. These results impart the potential usefulness of the MSS to food, cosmetics and other applications.展开更多
Cheese has recently gained a lot of popularity around the world. This experi<span>ment was carried out to make cheese from skim milk with the addition of</span> garlic paste. This study </span><sp...Cheese has recently gained a lot of popularity around the world. This experi<span>ment was carried out to make cheese from skim milk with the addition of</span> garlic paste. This study </span><span style="font-size:10.0pt;font-family:"">focused</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">on</span><span style="font-size:10.0pt;font-family:""> the impact of garlic paste on the physicochemical properties of cheese. Cheese samples S1, S2, S3, and S4 were prepared with 0%, 1%, 3%, and 5% garlic paste, respectively, where S1 was the control</span><span style="font-size:10.0pt;font-family:""> sample</span><span style="font-size:10.0pt;font-family:"">. Compared to sample S1, the higher proportion of garlic paste incorpora<span>tion resulted in higher viscosity and water holding capacity;nevertheless, </span>lower values for syneresis</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">were obtained. Although no significant change was observed in the pH values, samples S4 (5% garlic) and S1 (0% garlic) exhibited <span>the highest and lowest pH, respectively. The results in this investigation re</span>vealed <span>that garlic inclusion had a substantial impact on the physicochemical para</span>meters of the skim milk cheese.展开更多
Marginalization and abandonment of paddy terraces are widespread,but their effects on the sustainability of subsequent agricultural production are still unknown.Hani Paddy Terraces,included in Globally Important Agric...Marginalization and abandonment of paddy terraces are widespread,but their effects on the sustainability of subsequent agricultural production are still unknown.Hani Paddy Terraces,included in Globally Important Agriculture Heritage Systems,are threatened by paddy fields drainage.Here,changes in terrace structure,the productivity of topsoil(0-20 cm),and soil water holding capacity at 0-70 cm depth were determined in a case study of Hani Paddy Terraces in Amengkong River Basin in Yuanyang County in Southwestern China,which had been converted into dryland terraces for 2-14 years.Our results showed that:(1)The degree of terrace structures degradation exhibited a U-shaped curve with increasing time since draining,with those drained for 5-9 years having the best structure;(2)Soil productivity index decreased first and then increased with time after conversion;(3)Maximum water holding capacity at 0-70 cm soil depth dramatically decreased after conversion and such trend became increasingly obvious with increasing time since conversion.Our study revealed that drainage of paddy terraces along with associated changes in crop and field management led to an increase in soil productivity,but degradation of terrace structures and a decrease in water holding capacity will inhibit restoration to paddy terraces.These findings enhance the understanding of the biophysical changes due to marginalization in paddy terraces.展开更多
Defatted chickpea flour(DCF),which is a by-product of chickpea oil extraction industry,is rich in nutrients that are beneficial to human health.In this study,the effects of temperature and DCF variation on the rheolog...Defatted chickpea flour(DCF),which is a by-product of chickpea oil extraction industry,is rich in nutrients that are beneficial to human health.In this study,the effects of temperature and DCF variation on the rheological properties,water holding capacity,freeze-thaw stability and microstructure of DCF heat induced gels were investigated.The results showed that the viscoelasticity,frequency dependence,and resistance strength of heat induced gels increased significantly with the increase of temperature and DCF variation.The degree of denaturation and water retention of heat induced gels increased significantly with increased variables within the temperature and variation windows of 75℃ to 95℃ and 13%to 21%.The CLSM results revealed that variations of both temperature and DCF variation could cause the proteins in the heat induced gels to aggregate gradually and to form protein aggregations.When temperature or variation exceeded certain value(85℃ or 17%),the protein aggregations broke up and the protein clusters became smaller and more homogeneous.Therefore,the heat induced gels presented better water holding capacity,viscoelasticity,structural stability and gel property at a temperature of 95℃ or a DCF variation of 21%within the present experimental range.展开更多
Biochar, as a kind of soil amendment, has important effects on soil water retention. In this research, 4 different kinds of biochars were used to investigate their influences on hydraulic properties and water evaporat...Biochar, as a kind of soil amendment, has important effects on soil water retention. In this research, 4 different kinds of biochars were used to investigate their influences on hydraulic properties and water evaporation in a sandy soil from Hebei Province, China. Biochar had strong absorption ability in the sandy soil. The ratio of water content in the biochar to that in the sandy soil was less than the corresponding ratio of porosity. Because of the different hydraulic properties between the sandy soil and the biochar, the saturated hydraulic conductivity of the sandy soil gradually decreased with the increasing biochar addition. The biochar with larger pore volume and average pore diameter had better water retention. More water was retained in the sandy soil when the biochar was added in a single layer, but not when the biochar was uniformly mixed with soil. Particle size of the added biochar had a significant influence on the hydraulic properties of the mixture of sand and biochar. Grinding the biochar into powder destroyed the pore structure, which simultaneously reduced the water absorption ability and hydraulic conductivity of the biochar. For this reason, adding biochar powder to the sandy soil would not decrease the water evaporation loss of the soil itself.展开更多
To further understand the adsorption characteristics of different-type leaf surfaces adsorbing pesticide droplets and reveal the adsorption mechanism of pesticide droplets on non-smooth leaves,non-smooth leaves of 12 ...To further understand the adsorption characteristics of different-type leaf surfaces adsorbing pesticide droplets and reveal the adsorption mechanism of pesticide droplets on non-smooth leaves,non-smooth leaves of 12 kinds of typical target plants were investigated in this study.The parameters of surface morphological characteristics were measured,which include contact angle between leaves and water droplets,water holding capacity surface tension,polar component,dispersion component and other quantitative range of indicators and variation by modern means.The relationships between the indicators and water holding capacity were investigated respectively.The experimental results show that the number of trichomes,epidermal wax,morphology and distribution characteristics have influences on adsorption characteristics of the water droplets.There is a negative correlation between free energy of obverse side and the water holding capacity(R=−0.447)while the free energy of reverse side and the water holding capacity show a positive correlation(R=0.212).Also,there is a negative correlation between polar component of obverse side and the water holding capacity(R=−0.357)while the polar component of reverse side and the water holding capacity in plant leaves show a positive correlation(R=0.149).The research can provide a scientific theory for reasonable spraying of pesticide in the agricultural production,and can be a reference for the development of pesticide adjuvants and bionic pesticides.展开更多
Constructed Technosols may be an alternative for creating urban green spaces. However, the hydro-structural properties emer- ging from the assembly of artefacts have never been documented. The soil shrinkage curve (...Constructed Technosols may be an alternative for creating urban green spaces. However, the hydro-structural properties emer- ging from the assembly of artefacts have never been documented. The soil shrinkage curve (SSC) could provide relevant structural information about constructed Technosols, such as the water holding capacity of each pore system (macropores and micropores). The objectives of this study were (i) to evaluate the SSC and water retention curve (WRC) to describe the structure of constructed Tech- nosols and (ii) to understand the influence of organic matter content on soil hydro-structural properties. In this study, Technosols were obtained by mixing green waste compost (GWC) with the material excavated from deep horizons of soil (EDH). The CWC was mixed with EDH in six different volumetric percentages from 0% to 50% (GWC/total). The GWC and EDH exhibited highly divergent hydro-structural properties: the SSC was hyperbolic for GWC and sigmoid for EDH. All six mixture treatments (0%, 10%, 20%, 30%, 40% and 50% GWC) exhibited the classical sigmoid shape, revealing two embedded levels of pore systems. The 20% GWC treatment was hydro-structurally similar to the 30% and 40% GWC treatments; so, a large quantity of expansive GWC is unnecessary. The relation with the GWC percentage was a second-degree equation for volumetric available water in micropores, but was linear for volumetric available water in macropores and total volumetric available water. Total volumetric available water in the 50% GWC treatment was twice as high as that in the 0% GWC treatment. By combining SSCs and WRCs, increasing the GWC percentage increased water holding capacity by decreasing the maximum equivalent size of water-saturated micropores at the shrinkage limit and increasing the maximum equivalent size of water-saturated macropores, resulting in an increased range of pore diameter able to retain available water.展开更多
文摘[ Objective] To explore the effects of different proportion of bee pollen on the water holding capacity of pork in Duroc Landrace x Yorkshire growing-finishing pigs in order to determine the optimal proportion. [ Method] A total of 80 Duroc x Landrace x Yorkshire growing-finishing pigs, weighing (10.0 ± 1.0) kg, were randomly divided into five groups. The experimental period was 120 d including the 5-day pre-feecling period. The corn-soybean meal was not replaced during the whole period. All pigs had free access to feed and water. The pigs were fasting for 24 h but not prohibited from feed before the beginning. Group I was the control group reared with the diet not supplemented bee pollen. The pigs in group II, III ,IV and V were reared with the diet supplemented bee pollen at the concentration of 1%, 3%, 5% and 7%, respectively. After slaughtering, eye muscle was used for determination of water holding capacity through fast filter paper method, drip loss method, cooking loss method and Na- pole yield determination method. [ Resultl With the increase of the proportion of bee pollen, the water holding capacity of pork was first good and then poor. The addition of bee pollen at the concentration of 5% significantly reduced the drip loss of pork and the water holding capacity which was detected by fast filter paper method, but the cooking loss and Napole yield were not significantly influenced. [ Condmion] The bee pollen can effectively improve the water holding capacity of pork in Duroc x Landrace x Yorkshire growing-finishing pigs, and the optimal proportion is 5%.
文摘Rapid expansion of cultivated bamboo negatively impacts on biodiversity and soil microbial community.As such,it is important to properly manage and use bamboo to prevent and control such issues.This study focuses on optimizing pyrolysis conditions to produce bamboo biochar for agricultural soil amendment,particularly soil potassium(K)and water holding capacity.Bamboo chips were pyrolyzed under nitrogen gas at 400,600,and 800℃ for 1 and 2 h of retention.A total of six biochar products were created:400-1(i.e.,400℃ in 1 h),400-2,600-1,600-2,800-1,and 800-2.The 600℃ bamboo biochar products were observed to have the greatest potential in increasing soil K and water holding capacity.The 600-1 product had the highest potassium content(4.87%),with a water holding capacity of 3.73 g g^(−1),while the 600-2 product had the second-highest potassium content(4.13%)and the highest water holding capacity(4.21 g g^(−1))and cation exchange capacity.The K release in 600℃ products was larger and slower than that of the 400℃ and 800℃ products,respectively.The results also indicated that the physicochemical characteristics of bamboo biochar,such as yield,pH,surface area,water holding capacity,and K content,were significantly impacted by temperature,retention time,or a combination of these parameters.The outcomes from this study are a valuable reference for bamboo biochar production targeting agricultural soil amendment,particularly when it is directed at increasing soil K and water holding capacity.
基金financially supported by the National Key R&D Program of China(Grant no.2018YFD0500402)S&T Program of Hebei(199A7310H)。
文摘The current study was carried out to detect the effect of dietary guanidinoacetic acid(GAA)supplementation on carcass characteristics and meat quality in finishing pigs fed different dietary crude protein(CP)levels.Sixty-four barrows with an initial body weight of 73.05±2.34 kg were randomly allocated into 1 of 4 dietary treatments in a 2(100%vs.125%NRC CP level)×2(0 vs.300 mg/kg GAA)factorial arrangement(n=7).The feeding trial lasted for 49 d.GAA supplementation significantly reduced drip loss(P=0.01),free water distribution(T23peak area ratio)(P=0.05)and the concentrations of free alanine,threonine,methionine and isoleucine(P<0.05);but increased total glycine content(P=0.03)in the longissimus dorsi muscle of finishing pigs regardless of the dietary CP levels.Furthermore,primary myogenic cell differentiation system was employed to investigate the influence of inclusion of GAA on free amino acid concentrations in myotubes(n=4)and validate the finding in the animal feeding trial.We found that GAA inclusion in culture medium also decreased intracellular concentrations of free alanine,threonine,methionine,isoleucine,valine and proline in differentiated primary myogenic cells in vitro(P<0.05).Meanwhile,relative to diets with 100%NRC CP level,the intake of diets with 125%NRC CP level improved sarcoplasmic protein solubility,increased the contents of carnosine and total free amino acids as well as flavor amino acids in the longissimus dorsi muscle and decreased backfat thickness at the 6-7th ribs in pigs(P<0.05).In addition,we observed that the impact of dietary GAA supplementation on the last rib fat thickness,shear force,and free lysine content in the longissimus dorsi muscle was dependent on dietary CP levels(P<0.05).Collectively,dietary GAA supplementation can reduce drip loss,decrease the concentrations of free amino acids and flavor amino acids of fresh meat independent of dietary CP levels.
文摘Relationship of soil and water is generally considered as important in soil science. To specify it further we studied two different soils in 2012-2013, three additional soils once and made several series of experiments with drying and wetting of the soils. Principal parameters studied were the gravimetric water content (GWC), water holding capacity (WHC), soil organic matter (SOM), their correlations and rates of change in drying or wetting. The three parameters are significantly inter-correlated. Distribution of GWC in the replicates of soils dried both in nature and in experiments was narrower than that in wet soils, while WHC changed less in drying. The correlations (GWC- WHC) became steeper (the slope coefficient higher) and the coefficient of determination (R2) lower. Attempts to increase WHC in wet soils with a high WHC even further were not successful. Drying may be fast or slow;rates of increase of WHC in wetting were all low, both in field and in the experiments, less than 0.1 g (H2O) g-1 (soil)·day-1. None of the three parameters can be considered as fixed characteristics of forest soils.
基金Supported by National Natural Science Foundation of China(40871119)Key Science and Technology Program of Shaanxi Province,China(2007K01-15-1)~~
文摘[Objective] This study was to reveal the effect of different land use patterns on physical characteristics of soil water in the Yellow River wetland in Shaanxi Province.[Method]Taking Yellow River wetland in Shaanxi Province as experimental plot,we compared the physical properties of the soil water under different land use patterns and studied the physical properties and the change law of soil water during the wetland degeneration process.[Result]Under different land use patterns,soil bulk density rose with the increase of soil depth.During the degeneration process of from river wetland to reclaimed wetland(paddy field),finally to abandoned land owing to salinization,the mean soil bulk density reduced correspondingly from 1.474 to 1.522 g/cm3,finally to 1.593 g/cm3 when abandoned.Accompanying wetland degeneration,soil became compact increasingly,and the indicators of soil porosity(total porosity,capillary porosity,non-capillary porosity)were also reduced with the change of land use patterns,in which,capillary porosity and total porosity reached the extremely significant level with the change of land use patterns,and non-capillary porosity reached significant level.The changes of soil porosity condition accelerated the deterioration of wetland.Under different land use patterns,the maximum soil moisture capacity,capillary moisture capacity and minimum moisture capacity all showed a similar change law.Compared with wetland,the maximum soil moisture capacity of reclaimed land(paddy field)and salinized land respectively decreased by 5.7% and 22.3%,capillary moisture capacity by 0.2% and 19.4%,minimum moisture capacity by 2.7% and 15.9%.Of the three land use patterns,wetland displayed both higher water holding capacity and water drainage capacity over reclaimed land(paddy field)and salinized land.By comparison with wetland,the reclaimed land(paddy field)and salinized land respectively decreased by 12.4% and 15.2% in total water holding capacity,and by 2.7% and 15.9% in total water drainage capacity.[Conclusion]To conserve the water resource in Yellow River wetland,regulate the hydrological cycle and enhance drought and water logging resistances,it should be noted that reasonable countermeasures be taken to exploit the state-owned forest land and paddy field around the wetland and the related resources.
基金Supported by Science and Technology Foundation of Guizhou Province[Qiankehe-J(2009)No.2108)]Guizhou Normal University Fund for Doctor(2008)~~
文摘[Objective]The aim of this study was to select tartary buckwheat material with better health function.[Method]Used 35 kinds of tartary buckwheat as experimental materials,and the water holding capacity and expansion capacity had been determined.[Result] The water holding capacity of 35 kinds of tartary buckwheat will change in the range of 248.5%-341.4% with an average of 283.0%(the holding capacity of T324 was the highest),while the change of expansion capacity changed between 0.50 and 1.50 ml/g with an average of 1.05 ml/g(the expansion capacity of T463 was the highest).[Conclusion]This study had provided theoretical basis for screening better tartary buckwheat variety and its application.
基金This work is supported by the International Paper Co.from Brazil(Process 23112.000670/2015-59)by Brazilian National Council for Scientific and Technological Development(CNPq)in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior-Brasil(CAPES)-Finance Code 001.
文摘Although forests play important roles in the hydrological cycle,there is little information that relates the water retention capacity of litter in areas under passive restoration,especially in Cerrado savannas.This study relates litter levels to water holding capacity and effective water retention among forest fragments under different passive restoration stages:46,11,and 8 years to better understand litter hydrological functions in the Cerrado.Water retention capacity and effective water retention capacity of litters(unstructured materials,branches and leaves)in the field were monitored on a monthly basis.Total litter accumulation at 46 years was significantly higher than that of the other succession stages.Unstructured litter mass was significantly higher than that of leaves and branches.The 46-year stage had the highest water holding capacity in the leaf fraction,followed by unstructured material and branches.Although the water holding capacity was lower in the oldest resto-ration,this site showed the highest efficiency under field conditions.The process was quickly reestablished,as the 11-year restoration showed results closer to that for the 46-year stage in comparison to the area at 8 years.Thus,passive restoration plays a key role in soil water mainte-nance due to the influence of litter in Cerrado savannas.Deforestation and the imminent need of restoring degraded sites,highlight the need for further studies focused on bet-ter understanding of the process of forest restoration and its temporal effect on soil water recovery dynamics.
文摘After water imbibition, the outer layer seed coat of shaddock (Citrus grandis Osbeck) produces transparent gel-like mucilage (MSS), but its characteristics have never been studied before. This study aimed to assess the physico-chemical and functional properties of MSS. Extractions of MSS with deionized water at room temperature yielded about 3.5% based on the dry weight of seed. The major components were neutral sugars and uronic acids in the amounts of 33.5% and 49.6%, respectively. The acidic nature of MSS was confirmed by ruthenium red staining. Its water holding capacity and viscosity were 44.53 g•g<sup>-1</sup> DW and 1660 cP at 10 g/L, respectively. MSS showed a weak quenching activity against DPPH radical, and moderate ferrous ion-chelating and superoxide anion radical scavenging activities, with IC<sub>50</sub> value of 1.5 g/L and 1.1 g/L, respectively. A methyl thiazolyl tetrazolium (MTT) assay demonstrated that MSS significantly stimulated the viability of mouse skin fibroblasts (NIH/3T3) at 5 - 300 mg/L. These results impart the potential usefulness of the MSS to food, cosmetics and other applications.
文摘Cheese has recently gained a lot of popularity around the world. This experi<span>ment was carried out to make cheese from skim milk with the addition of</span> garlic paste. This study </span><span style="font-size:10.0pt;font-family:"">focused</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">on</span><span style="font-size:10.0pt;font-family:""> the impact of garlic paste on the physicochemical properties of cheese. Cheese samples S1, S2, S3, and S4 were prepared with 0%, 1%, 3%, and 5% garlic paste, respectively, where S1 was the control</span><span style="font-size:10.0pt;font-family:""> sample</span><span style="font-size:10.0pt;font-family:"">. Compared to sample S1, the higher proportion of garlic paste incorpora<span>tion resulted in higher viscosity and water holding capacity;nevertheless, </span>lower values for syneresis</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">were obtained. Although no significant change was observed in the pH values, samples S4 (5% garlic) and S1 (0% garlic) exhibited <span>the highest and lowest pH, respectively. The results in this investigation re</span>vealed <span>that garlic inclusion had a substantial impact on the physicochemical para</span>meters of the skim milk cheese.
基金This work was supported by the National Natural Science Foundation of China[grant numbers 41501592,42061044,42061074].The authors would like to thank Professor Xingwu Duan of Yunnan University for suggestions for experimental design and Jiancheng Deng of Yunnan University and the villagers of Amengkong for their assistance in fieldwork.
文摘Marginalization and abandonment of paddy terraces are widespread,but their effects on the sustainability of subsequent agricultural production are still unknown.Hani Paddy Terraces,included in Globally Important Agriculture Heritage Systems,are threatened by paddy fields drainage.Here,changes in terrace structure,the productivity of topsoil(0-20 cm),and soil water holding capacity at 0-70 cm depth were determined in a case study of Hani Paddy Terraces in Amengkong River Basin in Yuanyang County in Southwestern China,which had been converted into dryland terraces for 2-14 years.Our results showed that:(1)The degree of terrace structures degradation exhibited a U-shaped curve with increasing time since draining,with those drained for 5-9 years having the best structure;(2)Soil productivity index decreased first and then increased with time after conversion;(3)Maximum water holding capacity at 0-70 cm soil depth dramatically decreased after conversion and such trend became increasingly obvious with increasing time since conversion.Our study revealed that drainage of paddy terraces along with associated changes in crop and field management led to an increase in soil productivity,but degradation of terrace structures and a decrease in water holding capacity will inhibit restoration to paddy terraces.These findings enhance the understanding of the biophysical changes due to marginalization in paddy terraces.
基金financially supported by Joint Program of Beijing Natural Science Foundation Committee and Beijing Education Committee(KZ201810011017)Beijing Excellent Talent Training Project(2017000020124G100).
文摘Defatted chickpea flour(DCF),which is a by-product of chickpea oil extraction industry,is rich in nutrients that are beneficial to human health.In this study,the effects of temperature and DCF variation on the rheological properties,water holding capacity,freeze-thaw stability and microstructure of DCF heat induced gels were investigated.The results showed that the viscoelasticity,frequency dependence,and resistance strength of heat induced gels increased significantly with the increase of temperature and DCF variation.The degree of denaturation and water retention of heat induced gels increased significantly with increased variables within the temperature and variation windows of 75℃ to 95℃ and 13%to 21%.The CLSM results revealed that variations of both temperature and DCF variation could cause the proteins in the heat induced gels to aggregate gradually and to form protein aggregations.When temperature or variation exceeded certain value(85℃ or 17%),the protein aggregations broke up and the protein clusters became smaller and more homogeneous.Therefore,the heat induced gels presented better water holding capacity,viscoelasticity,structural stability and gel property at a temperature of 95℃ or a DCF variation of 21%within the present experimental range.
文摘Biochar, as a kind of soil amendment, has important effects on soil water retention. In this research, 4 different kinds of biochars were used to investigate their influences on hydraulic properties and water evaporation in a sandy soil from Hebei Province, China. Biochar had strong absorption ability in the sandy soil. The ratio of water content in the biochar to that in the sandy soil was less than the corresponding ratio of porosity. Because of the different hydraulic properties between the sandy soil and the biochar, the saturated hydraulic conductivity of the sandy soil gradually decreased with the increasing biochar addition. The biochar with larger pore volume and average pore diameter had better water retention. More water was retained in the sandy soil when the biochar was added in a single layer, but not when the biochar was uniformly mixed with soil. Particle size of the added biochar had a significant influence on the hydraulic properties of the mixture of sand and biochar. Grinding the biochar into powder destroyed the pore structure, which simultaneously reduced the water absorption ability and hydraulic conductivity of the biochar. For this reason, adding biochar powder to the sandy soil would not decrease the water evaporation loss of the soil itself.
基金This work was supported by the National Natural Science Foundation of China(No:50905071)National Science&Technology Pillar Programme(No:2009156)+1 种基金The Key Laboratory Fund for Project Bionic Technology of the Ministry of Education(No:K201101)Students’Innovative Research Plan of Jilin University(No:2011B45104).
文摘To further understand the adsorption characteristics of different-type leaf surfaces adsorbing pesticide droplets and reveal the adsorption mechanism of pesticide droplets on non-smooth leaves,non-smooth leaves of 12 kinds of typical target plants were investigated in this study.The parameters of surface morphological characteristics were measured,which include contact angle between leaves and water droplets,water holding capacity surface tension,polar component,dispersion component and other quantitative range of indicators and variation by modern means.The relationships between the indicators and water holding capacity were investigated respectively.The experimental results show that the number of trichomes,epidermal wax,morphology and distribution characteristics have influences on adsorption characteristics of the water droplets.There is a negative correlation between free energy of obverse side and the water holding capacity(R=−0.447)while the free energy of reverse side and the water holding capacity show a positive correlation(R=0.212).Also,there is a negative correlation between polar component of obverse side and the water holding capacity(R=−0.357)while the polar component of reverse side and the water holding capacity in plant leaves show a positive correlation(R=0.149).The research can provide a scientific theory for reasonable spraying of pesticide in the agricultural production,and can be a reference for the development of pesticide adjuvants and bionic pesticides.
基金the University of Damascus, Syria, for financial support of the Ph.D.(No.1473)
文摘Constructed Technosols may be an alternative for creating urban green spaces. However, the hydro-structural properties emer- ging from the assembly of artefacts have never been documented. The soil shrinkage curve (SSC) could provide relevant structural information about constructed Technosols, such as the water holding capacity of each pore system (macropores and micropores). The objectives of this study were (i) to evaluate the SSC and water retention curve (WRC) to describe the structure of constructed Tech- nosols and (ii) to understand the influence of organic matter content on soil hydro-structural properties. In this study, Technosols were obtained by mixing green waste compost (GWC) with the material excavated from deep horizons of soil (EDH). The CWC was mixed with EDH in six different volumetric percentages from 0% to 50% (GWC/total). The GWC and EDH exhibited highly divergent hydro-structural properties: the SSC was hyperbolic for GWC and sigmoid for EDH. All six mixture treatments (0%, 10%, 20%, 30%, 40% and 50% GWC) exhibited the classical sigmoid shape, revealing two embedded levels of pore systems. The 20% GWC treatment was hydro-structurally similar to the 30% and 40% GWC treatments; so, a large quantity of expansive GWC is unnecessary. The relation with the GWC percentage was a second-degree equation for volumetric available water in micropores, but was linear for volumetric available water in macropores and total volumetric available water. Total volumetric available water in the 50% GWC treatment was twice as high as that in the 0% GWC treatment. By combining SSCs and WRCs, increasing the GWC percentage increased water holding capacity by decreasing the maximum equivalent size of water-saturated micropores at the shrinkage limit and increasing the maximum equivalent size of water-saturated macropores, resulting in an increased range of pore diameter able to retain available water.