By using factor analysis method and establishing analysis indicator system from four aspects including crop production,poultry farming,rural life and township enterprises,the difference,features,and types of factors i...By using factor analysis method and establishing analysis indicator system from four aspects including crop production,poultry farming,rural life and township enterprises,the difference,features,and types of factors influencing the rural environmental pollution in the hilly area in Sichuan Province,China.Results prove that the major factor influencing rural environmental pollution in the study area is livestock and poultry breeding,flowed by crop planting,rural life,and township enterprises.Hence future pollution prevention and control should set about from livestock and poultry breeding.Meanwhile,attention should be paid to the prevention and control of rural environmental pollution caused by rural life and township enterprise production.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
The carbon cycle of terrestrial ecosystems is an important scientific issue in global climate change research.Plantation forest plays an important role in terrestrial carbon budget in China.In this study,eddy covarian...The carbon cycle of terrestrial ecosystems is an important scientific issue in global climate change research.Plantation forest plays an important role in terrestrial carbon budget in China.In this study,eddy covariance flux data measured at Xiaolangdi forest ecosystem research station（XLD） in 2007 and 2008 are used to analyze the seasonal variation and meteorological control of CO2 flux in a 30-yr-old mixed plantation.The plantation forest mainly consists of Quercus variabilis,Platycladus orientalis,and Robinia pseudoacacia.The results show that the seasonal variations of net ecosystem exchange of CO2（NEE）,gross primary production（GPP）,and ecosystem respiration（Re） display single-peak curves.The maximum of carbon sequestration appears during May and June each year.The relative contribution of carbon release from ecosystem respiration to GPP varied slightly between 2007 and 2008.The relationship between NEE and photosynthetic active radiation（Qp） accords with the rectangular hyperbola model on diurnal scale,and shows a good linear correlation on monthly scale.The ecosystem photosynthetic parameters：the maximum photosynthetic rate（Pmax）,the ecosystem photosynthetic photonyield（α）,and the daytime ecosystem respiration（Rd） exhibit seasonal variations.Pmax reaches the maximum in August each year,with small interannual difference.The interannual differences of α and Rd are obvious,which is attributed to the changes of meteorological factors,such as solar radiation,vapor pressure deficit（D）,precipitation,etc.Parameters Re,GPP,and NEP（net ecosystem production） have obvious exponential relations with temperature on monthly scale.There is a hysteresis in the response of GPP and NEP to temperature,i.e.,the carbon sequestration is not the maximum when the temperature reaches the peak value.The Q10 values were 1.37 and 1.45 in 2007 and 2008,respectively.On monthly scale,Re,GPP,and NEE increase as D increases,but rise slowly and even decrease when D is higher than 1.5 kPa.展开更多
The rural social space quality is an important indicator to measure the living standard and thinking ideas and so forth of rural residents in a certain region.In this paper,213 administrative villages in Longxi County...The rural social space quality is an important indicator to measure the living standard and thinking ideas and so forth of rural residents in a certain region.In this paper,213 administrative villages in Longxi County of the Loess Hilly Area,China are taken as evaluation units to construct the evaluation model of the rural social space quality.This paper deeply analyzed the variation patterns and their formation mechanism of the rural social space quality at a village scale,and proposed a governance model based on the rural social space quality.The results show that:(1)the social space quality levels of individual administrative villages show a gradually decreasing trend from the township seats to outward.The eastern part of Longxi County has a relatively high education level and living standard,and the western part has a relatively high population stability level and income level.(2)The rural social space quality is mainly in a ring structure,supplemented by the interlaced structure.The core area is the towns and their surrounding areas,while the transition area,marginal area,and other areas are expanded around the core area.(3)Social forces and spatial effects jointly shape the variation of the rural social space quality.Social organizations provide a driving force for the allocation of elements,and interweaving with the spatial effects lead to the differences in the social space quality.(4)The governance models of the rural social space quality are constructed based on the principles of retaining the rural“people”,optimizing the rural“land”,and developing the rural“industry”,so as to improve the rural centripetal force,core force,inner thrust,and source power.展开更多
基金Supported by National Science and Technology Support Program (2006BAJ05A13,2007BAD89B15)
文摘By using factor analysis method and establishing analysis indicator system from four aspects including crop production,poultry farming,rural life and township enterprises,the difference,features,and types of factors influencing the rural environmental pollution in the hilly area in Sichuan Province,China.Results prove that the major factor influencing rural environmental pollution in the study area is livestock and poultry breeding,flowed by crop planting,rural life,and township enterprises.Hence future pollution prevention and control should set about from livestock and poultry breeding.Meanwhile,attention should be paid to the prevention and control of rural environmental pollution caused by rural life and township enterprise production.
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 the Special Research Fund for Young Scholars of Research Institute of Forestry, Chinese Academy of Forestry(RIF2008-04)the 11th Five-Year National Sci. & Tech. Research Program of China (2006BAD03A11)
文摘The carbon cycle of terrestrial ecosystems is an important scientific issue in global climate change research.Plantation forest plays an important role in terrestrial carbon budget in China.In this study,eddy covariance flux data measured at Xiaolangdi forest ecosystem research station（XLD） in 2007 and 2008 are used to analyze the seasonal variation and meteorological control of CO2 flux in a 30-yr-old mixed plantation.The plantation forest mainly consists of Quercus variabilis,Platycladus orientalis,and Robinia pseudoacacia.The results show that the seasonal variations of net ecosystem exchange of CO2（NEE）,gross primary production（GPP）,and ecosystem respiration（Re） display single-peak curves.The maximum of carbon sequestration appears during May and June each year.The relative contribution of carbon release from ecosystem respiration to GPP varied slightly between 2007 and 2008.The relationship between NEE and photosynthetic active radiation（Qp） accords with the rectangular hyperbola model on diurnal scale,and shows a good linear correlation on monthly scale.The ecosystem photosynthetic parameters：the maximum photosynthetic rate（Pmax）,the ecosystem photosynthetic photonyield（α）,and the daytime ecosystem respiration（Rd） exhibit seasonal variations.Pmax reaches the maximum in August each year,with small interannual difference.The interannual differences of α and Rd are obvious,which is attributed to the changes of meteorological factors,such as solar radiation,vapor pressure deficit（D）,precipitation,etc.Parameters Re,GPP,and NEP（net ecosystem production） have obvious exponential relations with temperature on monthly scale.There is a hysteresis in the response of GPP and NEP to temperature,i.e.,the carbon sequestration is not the maximum when the temperature reaches the peak value.The Q10 values were 1.37 and 1.45 in 2007 and 2008,respectively.On monthly scale,Re,GPP,and NEE increase as D increases,but rise slowly and even decrease when D is higher than 1.5 kPa.
基金National Natural Science Foundation of China,No.41961033Natural Science Foundation of Gansu Province,No.20JR5RA519The Graduate Research Funding Project of Northwest Normal University in 2021,No.2021KYZZ01039。
文摘The rural social space quality is an important indicator to measure the living standard and thinking ideas and so forth of rural residents in a certain region.In this paper,213 administrative villages in Longxi County of the Loess Hilly Area,China are taken as evaluation units to construct the evaluation model of the rural social space quality.This paper deeply analyzed the variation patterns and their formation mechanism of the rural social space quality at a village scale,and proposed a governance model based on the rural social space quality.The results show that:(1)the social space quality levels of individual administrative villages show a gradually decreasing trend from the township seats to outward.The eastern part of Longxi County has a relatively high education level and living standard,and the western part has a relatively high population stability level and income level.(2)The rural social space quality is mainly in a ring structure,supplemented by the interlaced structure.The core area is the towns and their surrounding areas,while the transition area,marginal area,and other areas are expanded around the core area.(3)Social forces and spatial effects jointly shape the variation of the rural social space quality.Social organizations provide a driving force for the allocation of elements,and interweaving with the spatial effects lead to the differences in the social space quality.(4)The governance models of the rural social space quality are constructed based on the principles of retaining the rural“people”,optimizing the rural“land”,and developing the rural“industry”,so as to improve the rural centripetal force,core force,inner thrust,and source power.
