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
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
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
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.
