Taking an example of Majiayu Catchment Area (14.15 ha) in Taoyuan County of HunanProvince, the soil and water resources dynamics, fertility evolution characteristics andland productivity changing situation were studie...Taking an example of Majiayu Catchment Area (14.15 ha) in Taoyuan County of HunanProvince, the soil and water resources dynamics, fertility evolution characteristics andland productivity changing situation were studied. Fixed observation results from 1993to 2002 showed that pools covering about 15% of total area could store up 10% of surfacerunoff, keep 78.1% of eroded soil and 65.4% of lost nutrients. The yearly ratio ofinterception and evapotranspiration in land, storage in pools and drainage was 7:2:1,which ensured the resources and nutrients equilibrium and a benign recycle in thecatchment area system, and benefited the aquatic culture and helped to resist seasonaldrought. Moreover, the results showed that soil erosion modulus decreased significantly,equal to or lower than soil loss tolerance (≤500 tkm-2) in reddish yellow soil regions.Soil organic matter, total and available N content in sloping land, dryland and paddyfield increased steadily (>10%); water storage enhanced by more than 20% in sloping landand dryland in drought season; crop production increased by more than 20%; and productionof trees, fruits, tea and fish as well as land productivity increased yearly.展开更多
Results from ten-year (1990 - 1999) field experiments indicated that the productivity and the soil fertility of rice cropping system were significantly influenced by the fertilization system adopted in red soil area o...Results from ten-year (1990 - 1999) field experiments indicated that the productivity and the soil fertility of rice cropping system were significantly influenced by the fertilization system adopted in red soil area of China. Contrasting with no-fertili/er treatment (CK), yield-increase rate of organic matter cycling, chemical NPK and inorganic-organic fertilizer incorporation treatments were 56.5% , 62.5% and 80.7% , respectively. In the case of optimum fertilization system, the largest contribution of inorganic fertilizer to the yield was 38.5% while that of inorganic-organic fertilizer incorporation was 44.7%. The content of soil organic matter changed in tendency from decrease to equilibrium with heightened the extent of N, P and K incorporation while that of inorganic-organic fertilizer incorporation could be enhanced further. After N, P and K entered into the rice cropping system and maintained organic matter cycling in the system, the pools of total N, P and K could be strengthened.展开更多
A hundred and twenty-one households in Yujiang county, Jiangxi province were investigated by adopting questionnaire method, and the evaluation system of index was established according to the integrative, hierarchical...A hundred and twenty-one households in Yujiang county, Jiangxi province were investigated by adopting questionnaire method, and the evaluation system of index was established according to the integrative, hierarchical, scientific, practical, comparative and dynamic principles. The investigation data were firstly standardized and then processed with SPSS software. The index weight was confirmed by principal component analysis. Finally, the evaluation scale of ecoagriculture was calculated. The results showed that the evaluation value ranged from 0.141 to 0.689 for 121 households. Agricultural status of 113 households got the primary phase of ecoagriculture which accounting for 93.38%; 7 households into the second phase, representing 5.79% and only 1 household into the third phase according to the evaluation value. However, the ecoagriculture was divided into 5 stages, according to the evaluation value. Therefore, the ecoagriculture has huge potential to develop in red soil area, China.展开更多
Understanding soil nutrient distributions and the factors affecting them are crucial for fertilizer management and environmental protection in vulnerable ecological regions.Based on 555 soil samples collected in 2012 ...Understanding soil nutrient distributions and the factors affecting them are crucial for fertilizer management and environmental protection in vulnerable ecological regions.Based on 555 soil samples collected in 2012 in Renshou County,located in the purple soil hilly area of Sichuan Basin,China,the spatial variability of soil total nitrogen(TN),total phosphorus(TP)and total potassium(TK)was studied with geostatistical analysis and the relative roles of the affecting factors were quantified using regression analysis.The means of TN,TP and TK contents were 1.12,0.82 and 9.64 g kg^(–1),respectively.The coefficients of variation ranged from 30.56 to 38.75%and the nugget/sill ratios ranged from 0.45 to 0.61,indicating that the three soil nutrients had moderate variability and spatial dependence.Two distribution patterns were observed.TP and TK were associated with patterns of obvious spatial distribution trends while the spatial distribution of TN was characterized by higher variability.Soil group,land use type and topographic factors explained 26.5,35.6 and 8.4%of TN variability,respectively,with land use being the dominant factor.Parent material,soil group,land use type and topographic factors explained 17.5,10.7,12.0 and 5.0%of TP variability,respectively,and both parent material and land use type played important roles.Only parent material and soil type contributed to TK variability and could explain 25.1 and 13.7%of TK variability,respectively.More attention should focus on adopting reasonable land use types for the purposes of fertilizer management and consider the different roles of the affecting factors at the landscape scale in this purple soil hilly area.展开更多
Objective] This study almed to investigate the characteristics of soiI total porosity (STP) and various factors affecting soiI water content (SWC) in eucalyptus pIantation (EP), thereby providing references for ...Objective] This study almed to investigate the characteristics of soiI total porosity (STP) and various factors affecting soiI water content (SWC) in eucalyptus pIantation (EP), thereby providing references for soiI water utiIization in eucalyptus pIanting in the red soiI hiI y region of South China. [Method] In the same cIimatic region, soiI sampIes were coI ected from surface soiI Iayer (A), iI uvial horizon (B) and parent material horizon (C) in the upper sIope, middIe sIope and Iower sIope of eucalyptus pIantation, native forest and pine forest, respectiveIy, to determine the soiI porosity and soiI water content and analyze changes and various infIuencing factors of soiI water content in horizontal and vertical direction. [Result] Average soiI porosity in eucalyptus pIantation, native forest and pine forest was 45.9%, 41.4%and 55.3%, respectiveIy; soiI water content in these three forest stands was 13.3%, 13.4% and 15.5%, respectiveIy. In addition, soiI water content in these three forest stands exhibited no significant differences (P>0.05) among different soiI profiIes and sIope positions, but soiI water content in surface soiI Iayer varied significantIy (P<0.05) among different forest stands; in the horizontal direction, soiI water content exerted an extremeIy significant positive correIation with total coverage. [Conclusion] Total coverage of canopy Iayer, herb and Iitter Iayer is one of the most critical fac-tors affecting the changes of soiI water content in surface soiI Iayer of forest stands.展开更多
Landscape and quality attributes are major ecosystem characteristics closely associated with soil conservation service(SCS).However,the intrinsic mechanisms by which these two attributes influence SCS are still unclea...Landscape and quality attributes are major ecosystem characteristics closely associated with soil conservation service(SCS).However,the intrinsic mechanisms by which these two attributes influence SCS are still unclear.Therefore,this study quantitatively analyzed the landscape pattern,ecological quality,and SCS in the Lianshui River watershed(a typical soil and water loss area of red soil in southern China)and its sub-watersheds in 2019.The boosted regression tree model was used to explore the influence of 15 factors(i.e.,landscape and quality attributes)on SCS at the sub-watershed scale.According to the results,compared with the landscape attribute,the quality attribute of the watershed ecosystem could better explain the spatial heterogeneity of SCS across 66 sub-watersheds.The overall degree of influence of five quality factors on SCS reached 57.81%,with the highest being the normalized differential build-up and bare soil index(NDBSI),at 25.11%.Among 10 landscape factors,aggregation had the greatest influence on SCS,at 28.64%.The relationships between key influencing factors and SCS were nonmonotonic and non-linear,with threshold effects.For example,NDBSI values of 0.18e0.41 had a positive influence on SCS,while NDBSI values of 0.41e0.65 had a negative influence on SCS.The findings broaden our understanding of the response of SCS to changes in landscape and quality attributes at the sub-watershed scale,and could offer comprehensive support for soil erosion management in the watershed ecosystem.展开更多
To solve the problems of excessive soil lumps,broken branches and seedlings in pods and difficulty in removing impurities in the harvested pods of peanuts in the hilly areas of southern China,which is due to the high ...To solve the problems of excessive soil lumps,broken branches and seedlings in pods and difficulty in removing impurities in the harvested pods of peanuts in the hilly areas of southern China,which is due to the high soil viscosity and easy hardening,and to improve the soil removal effect of the peanut half-feed pod picker in hilly areas of China,this article designed a half-feed peanut-cleaning picker suitable for southern clay hilly areas and provided a detailed introduction to the overall structure,working principle,and adjustment methods of various operating parameters.Through field measurement experiments,the influencing factors and laws of soil removal performance indicators,such as the comprehensive soil removal rate and POD drop rate,were studied.The results showed that the comprehensive soil removal rate gradually increased with increasing soil patting frequency,soil patting amplitude,and picking roller speed,first increased and then decreased with increasing picking roller gap and gradually decreased with increasing soil patting plate gap and clamping conveyor chain speed.The comprehensive soil removal rate of the soil patting plate using the opposite patting method was greater than that of the swinging patting method.The soil removal pod drop rate increased gradually with increasing soil patting frequency and amplitude and decreased with increasing soil patting plate gap and clamping conveyor chain speed.The soil removal pod drop rate of the soil patting plate using swing patting was lower than that using the opposite patting method.The speed and gap of the picking roller had no effect on the soil removal pod drop rate.The frequency,amplitude,form,and gap of the soil patting plate had extremely significant impacts on the rate of decrease in the number of soil removal pod drop rate.The clamping conveyor chain speed had a significant impact,while the speed and gap of the picking roller had no significant impact.The influence of all factors on the comprehensive soil removal rate was extremely significant.This study provides a theoretical basis and technical reference for parameter optimization research on peanut-cleaning picking machines in the clay hilly areas of southern China.展开更多
基金funded by the Knowledge Innovation Program of Chinese Academy of Sciences(KZCX2-SW-415,KZCX3-SW-426).
文摘Taking an example of Majiayu Catchment Area (14.15 ha) in Taoyuan County of HunanProvince, the soil and water resources dynamics, fertility evolution characteristics andland productivity changing situation were studied. Fixed observation results from 1993to 2002 showed that pools covering about 15% of total area could store up 10% of surfacerunoff, keep 78.1% of eroded soil and 65.4% of lost nutrients. The yearly ratio ofinterception and evapotranspiration in land, storage in pools and drainage was 7:2:1,which ensured the resources and nutrients equilibrium and a benign recycle in thecatchment area system, and benefited the aquatic culture and helped to resist seasonaldrought. Moreover, the results showed that soil erosion modulus decreased significantly,equal to or lower than soil loss tolerance (≤500 tkm-2) in reddish yellow soil regions.Soil organic matter, total and available N content in sloping land, dryland and paddyfield increased steadily (>10%); water storage enhanced by more than 20% in sloping landand dryland in drought season; crop production increased by more than 20%; and productionof trees, fruits, tea and fish as well as land productivity increased yearly.
文摘Results from ten-year (1990 - 1999) field experiments indicated that the productivity and the soil fertility of rice cropping system were significantly influenced by the fertilization system adopted in red soil area of China. Contrasting with no-fertili/er treatment (CK), yield-increase rate of organic matter cycling, chemical NPK and inorganic-organic fertilizer incorporation treatments were 56.5% , 62.5% and 80.7% , respectively. In the case of optimum fertilization system, the largest contribution of inorganic fertilizer to the yield was 38.5% while that of inorganic-organic fertilizer incorporation was 44.7%. The content of soil organic matter changed in tendency from decrease to equilibrium with heightened the extent of N, P and K incorporation while that of inorganic-organic fertilizer incorporation could be enhanced further. After N, P and K entered into the rice cropping system and maintained organic matter cycling in the system, the pools of total N, P and K could be strengthened.
文摘A hundred and twenty-one households in Yujiang county, Jiangxi province were investigated by adopting questionnaire method, and the evaluation system of index was established according to the integrative, hierarchical, scientific, practical, comparative and dynamic principles. The investigation data were firstly standardized and then processed with SPSS software. The index weight was confirmed by principal component analysis. Finally, the evaluation scale of ecoagriculture was calculated. The results showed that the evaluation value ranged from 0.141 to 0.689 for 121 households. Agricultural status of 113 households got the primary phase of ecoagriculture which accounting for 93.38%; 7 households into the second phase, representing 5.79% and only 1 household into the third phase according to the evaluation value. However, the ecoagriculture was divided into 5 stages, according to the evaluation value. Therefore, the ecoagriculture has huge potential to develop in red soil area, China.
基金supported by grants from the National Key Research and Development Program of China (SQ2018YFD080041)the Science Fund of the Education Department of Sichuan Province, China (16ZB0048)
文摘Understanding soil nutrient distributions and the factors affecting them are crucial for fertilizer management and environmental protection in vulnerable ecological regions.Based on 555 soil samples collected in 2012 in Renshou County,located in the purple soil hilly area of Sichuan Basin,China,the spatial variability of soil total nitrogen(TN),total phosphorus(TP)and total potassium(TK)was studied with geostatistical analysis and the relative roles of the affecting factors were quantified using regression analysis.The means of TN,TP and TK contents were 1.12,0.82 and 9.64 g kg^(–1),respectively.The coefficients of variation ranged from 30.56 to 38.75%and the nugget/sill ratios ranged from 0.45 to 0.61,indicating that the three soil nutrients had moderate variability and spatial dependence.Two distribution patterns were observed.TP and TK were associated with patterns of obvious spatial distribution trends while the spatial distribution of TN was characterized by higher variability.Soil group,land use type and topographic factors explained 26.5,35.6 and 8.4%of TN variability,respectively,with land use being the dominant factor.Parent material,soil group,land use type and topographic factors explained 17.5,10.7,12.0 and 5.0%of TP variability,respectively,and both parent material and land use type played important roles.Only parent material and soil type contributed to TK variability and could explain 25.1 and 13.7%of TK variability,respectively.More attention should focus on adopting reasonable land use types for the purposes of fertilizer management and consider the different roles of the affecting factors at the landscape scale in this purple soil hilly area.
基金Supported by National Natural Science Foundation of China(U1033004)Open Fund of Key Laboratory of Plant Nutrition and Fertilizer,Ministry of Agriculture(2012-03)+3 种基金Major Science and Technology Project of Guangxi Zhuang Autonomous Region(GKZ1347001)Natural Science Foundation of Guangxi Zhuang Autonomous Region(2012GXNSFAA053066)Special Fund for the Basic Research and Operating Expenses of Guangxi Academy of Agricultural Sciences(GNK2013YM11,GNK2015YM11)Open Project of Guangxi Key Laboratory of Superior Timber Trees Resource Cultivation(13B0201)~~
文摘Objective] This study almed to investigate the characteristics of soiI total porosity (STP) and various factors affecting soiI water content (SWC) in eucalyptus pIantation (EP), thereby providing references for soiI water utiIization in eucalyptus pIanting in the red soiI hiI y region of South China. [Method] In the same cIimatic region, soiI sampIes were coI ected from surface soiI Iayer (A), iI uvial horizon (B) and parent material horizon (C) in the upper sIope, middIe sIope and Iower sIope of eucalyptus pIantation, native forest and pine forest, respectiveIy, to determine the soiI porosity and soiI water content and analyze changes and various infIuencing factors of soiI water content in horizontal and vertical direction. [Result] Average soiI porosity in eucalyptus pIantation, native forest and pine forest was 45.9%, 41.4%and 55.3%, respectiveIy; soiI water content in these three forest stands was 13.3%, 13.4% and 15.5%, respectiveIy. In addition, soiI water content in these three forest stands exhibited no significant differences (P>0.05) among different soiI profiIes and sIope positions, but soiI water content in surface soiI Iayer varied significantIy (P<0.05) among different forest stands; in the horizontal direction, soiI water content exerted an extremeIy significant positive correIation with total coverage. [Conclusion] Total coverage of canopy Iayer, herb and Iitter Iayer is one of the most critical fac-tors affecting the changes of soiI water content in surface soiI Iayer of forest stands.
基金This work was supported by the Chinese Natural Science Foundation Program[grant number 31960331].
文摘Landscape and quality attributes are major ecosystem characteristics closely associated with soil conservation service(SCS).However,the intrinsic mechanisms by which these two attributes influence SCS are still unclear.Therefore,this study quantitatively analyzed the landscape pattern,ecological quality,and SCS in the Lianshui River watershed(a typical soil and water loss area of red soil in southern China)and its sub-watersheds in 2019.The boosted regression tree model was used to explore the influence of 15 factors(i.e.,landscape and quality attributes)on SCS at the sub-watershed scale.According to the results,compared with the landscape attribute,the quality attribute of the watershed ecosystem could better explain the spatial heterogeneity of SCS across 66 sub-watersheds.The overall degree of influence of five quality factors on SCS reached 57.81%,with the highest being the normalized differential build-up and bare soil index(NDBSI),at 25.11%.Among 10 landscape factors,aggregation had the greatest influence on SCS,at 28.64%.The relationships between key influencing factors and SCS were nonmonotonic and non-linear,with threshold effects.For example,NDBSI values of 0.18e0.41 had a positive influence on SCS,while NDBSI values of 0.41e0.65 had a negative influence on SCS.The findings broaden our understanding of the response of SCS to changes in landscape and quality attributes at the sub-watershed scale,and could offer comprehensive support for soil erosion management in the watershed ecosystem.
基金supported by the Jiangsu Agricultural Science and Technology Innovation Fund(Grant No.CX(23)3028)National Natural Science Foundation of China(Grant No.52105263)+2 种基金Key Laboratory of Modern Agricultural Intelligent Equipment in South China,Ministry of Agriculture and Rural Affairs,China(Grant No.HNZJ202201)Key Laboratory of Agricultural Equipment for Hilly and Mountainous Areas in Southeastern China(Co-construction by Ministry and Province),Ministry of Agriculture and Rural Affairs(Grant No.QSKF202304)Key Laboratory of Intelligent Equipment and Robotics for Agriculture of Zhejiang Province(Grant No.2022ZJZD2201).
文摘To solve the problems of excessive soil lumps,broken branches and seedlings in pods and difficulty in removing impurities in the harvested pods of peanuts in the hilly areas of southern China,which is due to the high soil viscosity and easy hardening,and to improve the soil removal effect of the peanut half-feed pod picker in hilly areas of China,this article designed a half-feed peanut-cleaning picker suitable for southern clay hilly areas and provided a detailed introduction to the overall structure,working principle,and adjustment methods of various operating parameters.Through field measurement experiments,the influencing factors and laws of soil removal performance indicators,such as the comprehensive soil removal rate and POD drop rate,were studied.The results showed that the comprehensive soil removal rate gradually increased with increasing soil patting frequency,soil patting amplitude,and picking roller speed,first increased and then decreased with increasing picking roller gap and gradually decreased with increasing soil patting plate gap and clamping conveyor chain speed.The comprehensive soil removal rate of the soil patting plate using the opposite patting method was greater than that of the swinging patting method.The soil removal pod drop rate increased gradually with increasing soil patting frequency and amplitude and decreased with increasing soil patting plate gap and clamping conveyor chain speed.The soil removal pod drop rate of the soil patting plate using swing patting was lower than that using the opposite patting method.The speed and gap of the picking roller had no effect on the soil removal pod drop rate.The frequency,amplitude,form,and gap of the soil patting plate had extremely significant impacts on the rate of decrease in the number of soil removal pod drop rate.The clamping conveyor chain speed had a significant impact,while the speed and gap of the picking roller had no significant impact.The influence of all factors on the comprehensive soil removal rate was extremely significant.This study provides a theoretical basis and technical reference for parameter optimization research on peanut-cleaning picking machines in the clay hilly areas of southern China.