The rapid expansion of cities seriously threatens the sustainable development of agriculture in China.Exploring the evolution law and influencing mechanism of agricultural regional system in the process of urbanizatio...The rapid expansion of cities seriously threatens the sustainable development of agriculture in China.Exploring the evolution law and influencing mechanism of agricultural regional system in the process of urbanization is of great significance for promoting sustainable development of agriculture in China.This paper takes the Loess Plateau(LP)as an example,and constructs a research framework to study the effect of urbanization on agricultural regional system through the lens of human-earth interaction,aiming at elucidating the evolutionary characteristics of agricultural regional system and revealing the impact law of urbanization.The results show that:(1)The growth trend of the evolution index of the agricultural regional system in the LP was significant,gradually evolving into a spatial pattern of"high in the north and south,low in the east and west".(2)The hot spot and sub-hot spot zones of the agricultural regional system evolution index in the LP were mainly distributed in the south and north,while the cold spot and sub-cold spot zones were primarily located in the center,east and west.(3)The levels of agricultural mechanization,agricultural land productivity,cropland area,and agricultural labor productivity were the main internal influencing factors of the agricultural regional system in the LP.The obstacle degree of agricultural mechanization level,cropland area,and the proportion of agricultural employees increased over time,while the obstacle degree of agricultural land productivity and grain yield capacity decreased.(4)The impact of population urbanization in the LP showed a spatial pattern of"inhibition in the southeast and promotion in the northwest",the impact of economic urbanization was dominated by inhibition,and the impact of land urbanization showed a spatial pattern of"promotion in the whole and inhibition in the local".This study provides ideas for the comprehensive research on the evolution and influencing factors of agricultural regional system,and offers practical references for achieving sustainable agricultural development in LP.展开更多
[Objective] The aim was to study climate changes and its effects on agriculture in Haidong agricultural region.[Method] Based on meteorology and agricultural observation data in Haidong agricultural region from 1961 t...[Objective] The aim was to study climate changes and its effects on agriculture in Haidong agricultural region.[Method] Based on meteorology and agricultural observation data in Haidong agricultural region from 1961 to 2009,the characteristics of climate change and its effects on agriculture were analyzed,and the possible effects of future climate change on Haidong agriculture were predicted according to the future climate scenarios provided by down-scaling climate model.[Result] Annual mean temperature in Haidong agricultural region during 1961-2009 showed obvious increase trend,with the rising rate of 0.37 ℃/10 a;annual mean precipitation and annual total sunshine duration went down slightly,with the climatic tendency of 3.70 mm/10 a and-27.55 h/10 a,respectively;climate extreme event occurred less frequently but became severer in recent 49 years.In future 100 years,temperature in Haidong agricultural region would go up significantly,with the slight increase of rainfall,and climate changes would affect agricultural production environment,arrangement,structure and productivity,namely increasing yield fluctuation of agricultural production,cost and investment and changing arrangement and structure.In order to adapt climate change,it was necessary to adjust agricultural structure,strengthen management,improve agricultural infrastructure,adopt new technology,increase the resistance ability of agricultural production to climate change actively and designedly,so as to improve adaptability,furthest reduce loss and realize potential benefit.[Conclusion] Our study could provide references for the decision of government and agricultural sector.展开更多
Taking the typical karst agricultural region, Xiaojiang watershed in Luxi of Yurman Province as a research unit, utilizing the groundwater quality data in 1982 and 2004, the aerial photos in 1982 and TM images in 2004...Taking the typical karst agricultural region, Xiaojiang watershed in Luxi of Yurman Province as a research unit, utilizing the groundwater quality data in 1982 and 2004, the aerial photos in 1982 and TM images in 2004, supported by the GIS, we probe into the law and the reason of its space-time change of the groundwater quality over the past 22 years in the paper. The results show： （1） There were obvious temporal and spatial changes of groundwater quality during the past 22 years. （2） Concentrations of NH4^＋, SO4^2- , NO3, NO2^-, Cl^- and the pH value, total hardness, total alkalinity increased significantly, in which NH4^2-, NO3, and NO2^- of groundwater exceeded the drinking water standards as a result of non-point pollution caused by the expansion of cultivated land and mass use of the fertilizer and pesticide. （3） Oppositely, Ca^2＋ and HCO3^- showed an obvious decline trend due to forest reduction and degradation and stony desertification. Meantime, there was a dynamic relation between the groundwater quality change and the land use change.展开更多
Supported by RS and GIS, the land use change from 1982 to 2003 were analyzed and the impacts of land use changes on pH value, organic matter, total N, total P, total K, available N, available P, and available K in soi...Supported by RS and GIS, the land use change from 1982 to 2003 were analyzed and the impacts of land use changes on pH value, organic matter, total N, total P, total K, available N, available P, and available K in soil of Xiaojiang watershed, a typical karst agricultural region of Yunnan Province, Southwest China were assessed. The following aspects are concluded. （1） The total land use converted during the past 20 years in Xiaojiang watershed covers an area of 610.12 km^2, of which 134.29 km^2 of forestland was converted into cultivated land, and 210 km^2 of.unused land was converted into cultivated land. （2） The rapid growth of population and the economic development were the main driving forces of land use change. （3） With the change in land use, the soil properties have been changed significantly. The pH, organic matter, total N, total P, total K, available N, available P and available K in soil in 1982 were 6.3, 38.02 g·kg^-1, 1.86 g·kg^-1, 1.63 g·kg^-1, 10.94 g·kg^-1, 114.42 g·kg^-1, 11.65 mg·kg^-1 and 64.69 mg·kg^-1g, respectively; and those in 2003 were 6.73, 25.26 g·kg^-1, 1.41 g·kg^-1, 0.99 g·kg^-1, 12.6 g·kg^-1, 113.43 mg·kg^-1, 11.11 mg·kg^-1 and 151.59 mg·kg^-1, respectively. Pared samples t-test of the tested indices of soil properties indicate that those indices have changed significantly during the last 20 years. But the soil properties changed differently, due to the differences in land use change. （4） Also, with the change in land use and management measures of soil, the modifications in soil properties which developed from carbonate rocks were more sensitive than those in the soil developed from sandstone.展开更多
[Objective] This study was to establish an optimized model for the allocation of agricultural fertilizer resources in Southern Xinjiang from the perspective of sustainable development.[Method] An optimized model for t...[Objective] This study was to establish an optimized model for the allocation of agricultural fertilizer resources in Southern Xinjiang from the perspective of sustainable development.[Method] An optimized model for the allocation of agricultural fertilizer resources was established based on their allocation structure.Combined with the actual agricultural production in Aksu areas of Southern Xinjiang,by establishing a rational evaluation index system,under the premise of considering the planting area constraints,the total water resources constraints and the security constraints of food production,we established the empirical optimal allocation model of the regional agricultural fertilizer resources in Aksu area of Southern Xinjiang.Moreover,we solved the model by using the search algorithm of computer and lingo programming.[Result] The increased economic benefit was near to 1.8 billion Yuan by adopting the optimal allocation methods,with a relative increment of about 34.4%.[Conclusion] Our results provided theoretical basis for achieving the sustainable development of agricultural economy in Southern Xinjiang.展开更多
Multiple cropping index （MCI） is the ratio of total sown area and cropland area in a region, which represents the regional time intensity of planting crops. Multiple cropping systems have effectively improved the ut...Multiple cropping index （MCI） is the ratio of total sown area and cropland area in a region, which represents the regional time intensity of planting crops. Multiple cropping systems have effectively improved the utilization efficiency and production of cropland by increasing cropping frequency in one year. Meanwhile, it has also significantly altered biogeochemical cycles. Therefore, exploring the spatio-temporal dynamics of multiple cropping intensity is of great significance for ensuring food and ecological security. In this study, MCI of Huang-Huai-Hai agricultural region with intensive cropping practices was extracted based on a cropping intensity mapping algorithm using MODIS Enhanced Vegetation Index （EVI） time series at 500-m spatial resolution and 8-day time intervals. Then the physical characteristics and landscape pattern of MCI trends were analyzed from 2000-2012. Results showed that MCI in Huang-Huai-Hai agricultural region has increased from 152% to 156% in the 12 years. Topography is a primary factor in determining more stable in hilly area than in plain area. An the spatial pattern dynamics of MCI, which is increase from 158% to 164% of MCI occurred irplain area while there was almost no change in hilly area with single cropping. The most active region of MCI change was the intersection zone between the hilly area and plain area. In spatial patterns, landscape of multiple cropping systems tended to be homogenized reflected by a reduction in the degree of fragmentation and an increase in the degree of concentration of cropland with the same cropping system.展开更多
An Ensemble Kalman Filter(EnKF)-based assimilation algorithm was implemented to estimate root-zone soil moisture(RZSM)using a Soil-Vegetation-Atmosphere Transfer(SVAT)model during a complete growing season of corn in ...An Ensemble Kalman Filter(EnKF)-based assimilation algorithm was implemented to estimate root-zone soil moisture(RZSM)using a Soil-Vegetation-Atmosphere Transfer(SVAT)model during a complete growing season of corn in Central Mexico.Synthetic and field soil moisture(SM)observations and NASA SMAP SM retrievals were used to understand the effect of vertically spatial updates and uncertainties in meteorological forcings on RZSM estimates.Assimilation of RZSM every 3 days using SM observations at 4 depths lowered the averaged standard deviation(ASD)and the root mean square error(RMSE)by 60%and 50%,respectively,compared to the open-loop ASD.The assimilation of synthetic SM at the top 0-5 cm obtained RZSM closer to observations compared to THEXMEX-18 SM measurements and SMAP SM retrievals.Differences between EnKF estimates and SM observations and SMAP SM retrievals are mainly due to misrepresentation of vegetation conditions.The results improved SM estimates up to 10-cm depth using SMAP SM retrievals;however,additional studies are needed to improve SM at deeper layers.The implemented methodology can estimate SM at the top 10 cm of the soil every 3 days to mitigate the impact of the climate change on agricultural production over rainfed areas,particularly in developing countries.展开更多
The regional agricultural system （RAS） can be divided into three subsystems： ecological, economic, and social. This article examines the use of the harmony coefficient （HC）, efficacy coefficient, rank of the harm...The regional agricultural system （RAS） can be divided into three subsystems： ecological, economic, and social. This article examines the use of the harmony coefficient （HC）, efficacy coefficient, rank of the harmony coefficient （RHC）, and its appraising index system within the RAS. The harmony coefficient function was developed using a variance coefficient and then applied to Ziyang District, Yiyang City in Hunan Province （ZYH）, China, as a test case. From 1995 to 2002, the HC of RAS increased from 0.2982 to 0.4826 and the RHC increased from 3 to 5, although the HC trend was an ＂n＂ type in general. This suggests that the HC was weakly maladjusted and the RAS was not harmonious. The HC of the ecological subsystem decreased from 0.3898 to 0.2850, and its RHC from 4 to 3, with the HC trend following the ＂n＂ type. For the economic subsystem, the HC value increased from 0.5767 to 0.7458 and the RHC from 6 to 8. However, the trend in HC for the economic subsystem was of the ＂U＂ type. The HC of the social subsystem increased slightly from 0.4948 to 0.4663, and the RHC did not change in value. From the HC trends, the HC curve of the economic subsystem is above the HC curve of ZYH and the HC curve of the ecological subsystem is below the HC curve of ZHY. Hence, the ZHY environment has been destroyed by economic development. Environment and social building should be regarded as important issues in the future and promoting RAS harmony development should be considered. The results of the theoretical analysis match fairly closely with reality, and suggest that the harmony theory is feasible in appraising RAS development phases.展开更多
Agricultural input and output status in southern Xinjiang,China is introduced,such as lack of agricultural input,low level of agricultural modernization,excessive fertilizer use,serious damage of environment,shortage ...Agricultural input and output status in southern Xinjiang,China is introduced,such as lack of agricultural input,low level of agricultural modernization,excessive fertilizer use,serious damage of environment,shortage of water resources,tremendous pressure on ecological balance,insignificant economic and social benefits of agricultural production in southern Xinjiang,agriculture remaining a weak industry,agricultural economy as the economic subject of southern Xinjiang,and backward economic development of southern Xinjiang.Taking the Aksu area as an example,according to the input and output data in the years 2002-2007,input-output model about regional agriculture of the southern Xinjiang is established by principal component analysis.DPS software is used in the process of solving the model.Then,Eviews software is adopted to revise and test the model in order to analyze and evaluate the economic significance of the results obtained,and to make additional explanations of the relevant model.Since the agricultural economic output is seriously restricted in southern Xinjiang at present,the following countermeasures are put forward,such as adjusting the structure of agricultural land,improving the utilization ratio of land,increasing agricultural input,realizing agricultural modernization,rationally utilizing water resources,maintaining eco-environmental balance,enhancing the awareness of agricultural insurance,minimizing the risk and loss,taking the road of industrialization of characteristic agricultural products,and realizing the transfer of surplus labor force.展开更多
Regional agriculture is the basis of regional sustainable development, so sustainable regional agricultural development is essential to the sustainable development of the whole society and becomes the focus of global ...Regional agriculture is the basis of regional sustainable development, so sustainable regional agricultural development is essential to the sustainable development of the whole society and becomes the focus of global research. The classification of regional agricultural structure is the basic work of regional agriculture study. This paper constructs index system （27 indices） of regional agricultural structure types with the three big indices： natural resources, developmental level of the agro-economy, and agro-ecological conditions. This paper also endows weight to every sub-classification index by means of AHP and obtains the comprehensive evaluation value of the three types of indices with arithmetic average weight approach. The regional agricultural structure can be classified into eight types in accordance with this evaluation results. The empirical study of China shows that the 31 provinces （municipalities and autonomous regions） are of different agriculture structural types. Finally, countermeasures of sustainsable agricultural development are put forward for the different agriculture structure features.展开更多
In the paper, three farms of Jiansanjiang Farming Bureau and five villages in of Dayushu Town in Fujin county randomly were taken as data sources for the investigation of household behavior of reclamation and agricult...In the paper, three farms of Jiansanjiang Farming Bureau and five villages in of Dayushu Town in Fujin county randomly were taken as data sources for the investigation of household behavior of reclamation and agricultural area under different land systems, and it can be concluded that the main content included production scale, arable land use structure, household behavior and economic benefits. By comparison and analysis, the advantages and disadvantages of reclamation and agricultural area can be found, which could provide references for agricultural land reform for achieving a more suitable socio-economic of efficient use and sustained and healthy development of agriculture.展开更多
Significance of nitrous oxide in atmospheric chemistry is reviewed briefly. Background concentration of N2O at Wudaoliang in Qinghai Province of Western China has been measured by collecting gas samples and analysing ...Significance of nitrous oxide in atmospheric chemistry is reviewed briefly. Background concentration of N2O at Wudaoliang in Qinghai Province of Western China has been measured by collecting gas samples and analysing them with electron capture-gas chromatography. The atmospheric concentration fluctuates in the range of 303-315 ppb with the mean value of 308 ppb. The emission rate of N2O in agriculture region of Northern China has been studied primarily. Fertilization, rain and temperature of soil appear conductible to N2O emission. The interactions between greenhouse effect and N2O emission have been discussed. The catalytic action of N2O in stratospheric ozone depletion processes and the effect of high N2O concentration on ozone depletion in stratosphere have been considered and discussed.展开更多
The state support of the agriculture is increasing with the globalization of Russia, the need to shape level and instruments in accordance with the WTO requirements. For Russia, rational state support of agriculture i...The state support of the agriculture is increasing with the globalization of Russia, the need to shape level and instruments in accordance with the WTO requirements. For Russia, rational state support of agriculture is topical according to the domestic economic problems： insufficient financing in Russia, in the regions; degradation of production facilities; turnover acreage reduction; reduction in livestock; and according to the external economic factors： the accession to the WTO, the transition to the Common Economic Space, and subsequently, the Eurasian Economic Union, global change conditions in the global food market, an increase in the world population, increasing demand for food resources, a significant increase in food prices on world markets, the increased activity of Russian agricultural producers in the world markets of grain products; ensuring of economic stability systems, critical analysis of the tools and the effectiveness of economic policy. According to the IMF, the economic has slowed down despite the state support for agriculture should stay a priority in the government＇s economic policy, in the regions.展开更多
Maize is one of our country quite important grain crops,its height output is an important pillar ensure that grain of our country is safe,if speedy science ascertaining that maize expediency area cultivating,it can pr...Maize is one of our country quite important grain crops,its height output is an important pillar ensure that grain of our country is safe,if speedy science ascertaining that maize expediency area cultivating,it can provide the most reliable decision-making reference to jobs such as agricultural regionalization,crop layout,accurate agriculture of essence.The article carries out a maize cultivating expediency research make use of the minute RS and GIS means,it can guarantee the results is timeliness and scientificalness.展开更多
Based on the data of the second national land survey and GIS method, this paper takes Fujin City as a study area to refl ect the similarities and differences of settlement system characteristics between reclamation an...Based on the data of the second national land survey and GIS method, this paper takes Fujin City as a study area to refl ect the similarities and differences of settlement system characteristics between reclamation and agricultural region in Heilongjiang Province, in order to discover the effect of land system on structure of settlement system. The results are as follows:(1) In the aspect of the spatial distribution pattern, settlement systems of both reclamation and agricultural region show clustered distribution, but those in reclamation region are denser;(2) The settlement systems of reclamation and agricultural regions can be divided into 4 levels, and their settlement systems are not incompatible with the 3 distribution patterns proposed in the center place theory, and show completely different hierarchical orders;(3) The average scale of reclamation settlement is smaller than that of agricultural settlement, but the difference is much more signifi cant;(4) The settlement systems in reclamation and agricultural regions have some problems, such as high proportion of the mini-settlements, and unreasonable space network system. Some measures should be taken, such as accelerating the reconstruction of the settlement system, optimizing the layout of settlement network system and transportation network, and promoting the connection between settlement systems in reclamation and agricultural regions in near future.展开更多
To combat the problem of residual film pollution and ensure the sustainable development of agriculture in oasis areas,a field experiment was carried out in 2019 at the Wuyi Farm Corps Irrigation Center Test Station in...To combat the problem of residual film pollution and ensure the sustainable development of agriculture in oasis areas,a field experiment was carried out in 2019 at the Wuyi Farm Corps Irrigation Center Test Station in Urumqi,Northwest China.Four types of biodegradable mulches,traditional plastic mulchs and a control group(bare land;referred to as CK)were compared,including a total of six different treatments.Effects of mulching on soil water and heat conditions as well as the yield and quality of processing tomatoes under drip irrigation were examined.In addition,a comparative analysis of economic benefits of biodegradable mulches was performed.Principal component analysis and gray correlation analysis were used to evaluate suitable mulching varieties for planting processing tomatoes under drip irrigation.Our results show that,compared with CK,biodegradable mulches and traditional plastic mulch have a similar effect on retaining soil moisture at the seedling stage but significantly increase soil moisture by 0.5%-1.5%and 1.5%-3.0%in the middle and late growth periods(P<0.050),respectively.The difference in the thermal insulation effect between biodegradable mulch and plastic mulch gradually reduces as the crop grows.Compared with plastic mulch,the average soil temperature at 5-20 cm depth under biodegradable mulches is significantly lowered by 2.04°C-3.52°C and 0.52°C-0.88°C(P<0.050)at the seedling stage and the full growth period,respectively,and the water use efficiency,average fruit yield,and production-investment ratio under biodegradable mulches were reduced by 0.89%-6.63%,3.39%-8.69%,and 0.51%-6.33%(P<0.050),respectively.The comprehensive evaluation analysis suggests that the black oxidized biological double-degradation ecological mulch made from eco-benign plastic is the optimal film type under the study condition.Therefore,from the perspective of sustainable development,biodegradable mulch is a competitive alternative to plastic mulch for large-scale tomato production under drip irrigation in the oasis.展开更多
Phosphorus（P） losses from agricultural soils contribute to eutrophication of surface waters. This field plot study investigated effects of rainfall regimes and P applications on P loss by surface runoff from rice（O...Phosphorus（P） losses from agricultural soils contribute to eutrophication of surface waters. This field plot study investigated effects of rainfall regimes and P applications on P loss by surface runoff from rice（Oryza sativa L.） and wheat（Triticum aestivum L.） cropping systems in Lake Taihu region, China. The study was conducted on two types of paddy soils（Hydromorphic at Anzhen site, Wuxi City, and Degleyed at Xinzhuang site, Changshu City, Jiangsu Province） with different P status, and it covered 3 years with low, high and normal rainfall regimes. Four rates of mineral P fertilizer, i.e., no P（control）, 30 kg P ha^（–1） for rice and 20 kg P ha^（–1） for wheat（P_（30＋20））, 75 plus 40（P_（75＋40））, and 150 plus 80（P_（150＋80））, were applied as treatments. Runoff water from individual plots and runoff events was recorded and analyzed for total P and dissolved reactive P concentrations. Losses of total P and dissolved reactive P significantly increased with rainfall depth and P rates（P〈0.0001）. Annual total P losses ranged from 0.36–0.92 kg ha^–1 in control to 1.13–4.67 kg ha^–1 in P150＋80 at Anzhen, and correspondingly from 0.36–0.48 kg h^–1 to 1.26–1.88 kg ha^–1 at Xinzhuang, with 16–49% of total P as dissolved reactive P. In particular, large amounts of P were lost during heavy rainfall events that occurred shortly after P applications at Anzhen. On average of all P treatments, rice growing season constituted 37–86% of annual total P loss at Anzhen and 28–44% of that at Xinzhuang. In both crop seasons, P concentrations peaked in the first runoff events and decreased with time. During rice growing season, runoff P concentrations positively correlated（P〈0.0001） with P concentrations in field ponding water that was intentionally enclosed by construction of field bund. The relative high P loss during wheat growing season at Xinzhuang was due to high soil P status. In conclusion, P should be applied at rates balancing crop removal（20–30 kg P ha^–1 in this study） and at time excluding heavy rains. Moreover, irrigation and drainage water should be appropriately managed to reduce runoff P losses from rice-wheat cropping systems.展开更多
Identifying the problem regions and regional problems, and thus improving regional policies, are crucial for the sustainable development of various economic entities. The coordinated development of industrialization, ...Identifying the problem regions and regional problems, and thus improving regional policies, are crucial for the sustainable development of various economic entities. The coordinated development of industrialization, informatization, urbanization and agricultural modernization（hereinafter referred to as ＂Sihua＂） is not only a practical need but an important strategic direction of integrating urban-rural development and regional development in recent China, and it also provides a significant perspective for identifying problem regions and regional problems so as to improve the regional policies. This study mainly aims to： firstly, establish a comprehensive evaluation index system so as to explore the spatial pattern of coordinated development of Sihua in China at prefecture level; secondly, to develop an evaluation criteria system to identify the problem regions and regional problems from the perspective of coordinated development of Sihua. This paper comes first in the scientific community to evaluate the coordinated development state of Sihua in China at prefecture level and identify the problem regions and regional problems from the perspective of Sihua development by quantitative analysis. This study may benefit the improvement of regional policies and thus contribute to the sustainable socio-economic development of China.展开更多
Based on explicating the definition of ecotone, this paper discussed emphatically the distribution and features of joint zone between land and water, transition zone between mountains and plains, and intersection zone...Based on explicating the definition of ecotone, this paper discussed emphatically the distribution and features of joint zone between land and water, transition zone between mountains and plains, and intersection zone between agricultural and animal husbandry regions. The geographic environment of the three ecotones were evaluated, their developing tendency predicted and the corresponding measures to be taken in the 21st century pointed out.展开更多
基金funded by the Major Program of National Natural Science Foundation of China(Grant No.42293271)the National Natural Science Foundation of China(Grant No.42171208).
文摘The rapid expansion of cities seriously threatens the sustainable development of agriculture in China.Exploring the evolution law and influencing mechanism of agricultural regional system in the process of urbanization is of great significance for promoting sustainable development of agriculture in China.This paper takes the Loess Plateau(LP)as an example,and constructs a research framework to study the effect of urbanization on agricultural regional system through the lens of human-earth interaction,aiming at elucidating the evolutionary characteristics of agricultural regional system and revealing the impact law of urbanization.The results show that:(1)The growth trend of the evolution index of the agricultural regional system in the LP was significant,gradually evolving into a spatial pattern of"high in the north and south,low in the east and west".(2)The hot spot and sub-hot spot zones of the agricultural regional system evolution index in the LP were mainly distributed in the south and north,while the cold spot and sub-cold spot zones were primarily located in the center,east and west.(3)The levels of agricultural mechanization,agricultural land productivity,cropland area,and agricultural labor productivity were the main internal influencing factors of the agricultural regional system in the LP.The obstacle degree of agricultural mechanization level,cropland area,and the proportion of agricultural employees increased over time,while the obstacle degree of agricultural land productivity and grain yield capacity decreased.(4)The impact of population urbanization in the LP showed a spatial pattern of"inhibition in the southeast and promotion in the northwest",the impact of economic urbanization was dominated by inhibition,and the impact of land urbanization showed a spatial pattern of"promotion in the whole and inhibition in the local".This study provides ideas for the comprehensive research on the evolution and influencing factors of agricultural regional system,and offers practical references for achieving sustainable agricultural development in LP.
基金Supported by Climate Change Project of China Meteorological Administration in 2010 (Evaluation Report on Climate Change in Northwest China)~~
文摘[Objective] The aim was to study climate changes and its effects on agriculture in Haidong agricultural region.[Method] Based on meteorology and agricultural observation data in Haidong agricultural region from 1961 to 2009,the characteristics of climate change and its effects on agriculture were analyzed,and the possible effects of future climate change on Haidong agriculture were predicted according to the future climate scenarios provided by down-scaling climate model.[Result] Annual mean temperature in Haidong agricultural region during 1961-2009 showed obvious increase trend,with the rising rate of 0.37 ℃/10 a;annual mean precipitation and annual total sunshine duration went down slightly,with the climatic tendency of 3.70 mm/10 a and-27.55 h/10 a,respectively;climate extreme event occurred less frequently but became severer in recent 49 years.In future 100 years,temperature in Haidong agricultural region would go up significantly,with the slight increase of rainfall,and climate changes would affect agricultural production environment,arrangement,structure and productivity,namely increasing yield fluctuation of agricultural production,cost and investment and changing arrangement and structure.In order to adapt climate change,it was necessary to adjust agricultural structure,strengthen management,improve agricultural infrastructure,adopt new technology,increase the resistance ability of agricultural production to climate change actively and designedly,so as to improve adaptability,furthest reduce loss and realize potential benefit.[Conclusion] Our study could provide references for the decision of government and agricultural sector.
基金Doctorate Foundation of Southwest University, No.SWNUB2005035 Open Foundation of Physical Geography of Southwest University, No.250-411109+2 种基金 Foundation of Science and Technology Committee of Chongqing, No.20027534 No.20048258 The project of Ministry of Land and Resources, No.200310400024
文摘Taking the typical karst agricultural region, Xiaojiang watershed in Luxi of Yurman Province as a research unit, utilizing the groundwater quality data in 1982 and 2004, the aerial photos in 1982 and TM images in 2004, supported by the GIS, we probe into the law and the reason of its space-time change of the groundwater quality over the past 22 years in the paper. The results show： （1） There were obvious temporal and spatial changes of groundwater quality during the past 22 years. （2） Concentrations of NH4^＋, SO4^2- , NO3, NO2^-, Cl^- and the pH value, total hardness, total alkalinity increased significantly, in which NH4^2-, NO3, and NO2^- of groundwater exceeded the drinking water standards as a result of non-point pollution caused by the expansion of cultivated land and mass use of the fertilizer and pesticide. （3） Oppositely, Ca^2＋ and HCO3^- showed an obvious decline trend due to forest reduction and degradation and stony desertification. Meantime, there was a dynamic relation between the groundwater quality change and the land use change.
基金The open foundation of physical geography of Southwest University, No.250-411109 Foundation of Science and Technology Committee of Chongqing, No.20027534+1 种基金 No.20048258 Project of Ministry of Land and Resources, No.200310400024
文摘Supported by RS and GIS, the land use change from 1982 to 2003 were analyzed and the impacts of land use changes on pH value, organic matter, total N, total P, total K, available N, available P, and available K in soil of Xiaojiang watershed, a typical karst agricultural region of Yunnan Province, Southwest China were assessed. The following aspects are concluded. （1） The total land use converted during the past 20 years in Xiaojiang watershed covers an area of 610.12 km^2, of which 134.29 km^2 of forestland was converted into cultivated land, and 210 km^2 of.unused land was converted into cultivated land. （2） The rapid growth of population and the economic development were the main driving forces of land use change. （3） With the change in land use, the soil properties have been changed significantly. The pH, organic matter, total N, total P, total K, available N, available P and available K in soil in 1982 were 6.3, 38.02 g·kg^-1, 1.86 g·kg^-1, 1.63 g·kg^-1, 10.94 g·kg^-1, 114.42 g·kg^-1, 11.65 mg·kg^-1 and 64.69 mg·kg^-1g, respectively; and those in 2003 were 6.73, 25.26 g·kg^-1, 1.41 g·kg^-1, 0.99 g·kg^-1, 12.6 g·kg^-1, 113.43 mg·kg^-1, 11.11 mg·kg^-1 and 151.59 mg·kg^-1, respectively. Pared samples t-test of the tested indices of soil properties indicate that those indices have changed significantly during the last 20 years. But the soil properties changed differently, due to the differences in land use change. （4） Also, with the change in land use and management measures of soil, the modifications in soil properties which developed from carbonate rocks were more sensitive than those in the soil developed from sandstone.
基金Supported by National Natural Science Foundation of China(30960188)Natural Science Fund of Principal Program from Tarim University(TDZKSS09010)+1 种基金Key Principal Program from Tarim University(TDZKZD09001)Quality Engineering Program from TarimUniversity(TDZGTD09004&DZGKC09085)~~
文摘[Objective] This study was to establish an optimized model for the allocation of agricultural fertilizer resources in Southern Xinjiang from the perspective of sustainable development.[Method] An optimized model for the allocation of agricultural fertilizer resources was established based on their allocation structure.Combined with the actual agricultural production in Aksu areas of Southern Xinjiang,by establishing a rational evaluation index system,under the premise of considering the planting area constraints,the total water resources constraints and the security constraints of food production,we established the empirical optimal allocation model of the regional agricultural fertilizer resources in Aksu area of Southern Xinjiang.Moreover,we solved the model by using the search algorithm of computer and lingo programming.[Result] The increased economic benefit was near to 1.8 billion Yuan by adopting the optimal allocation methods,with a relative increment of about 34.4%.[Conclusion] Our results provided theoretical basis for achieving the sustainable development of agricultural economy in Southern Xinjiang.
基金National Natural Science Foundation of China,No.41430861,No.41471453Strategic Priority Research Program,the Chinese Academy of Sciences(CAS),No.XDA20010202
文摘Multiple cropping index （MCI） is the ratio of total sown area and cropland area in a region, which represents the regional time intensity of planting crops. Multiple cropping systems have effectively improved the utilization efficiency and production of cropland by increasing cropping frequency in one year. Meanwhile, it has also significantly altered biogeochemical cycles. Therefore, exploring the spatio-temporal dynamics of multiple cropping intensity is of great significance for ensuring food and ecological security. In this study, MCI of Huang-Huai-Hai agricultural region with intensive cropping practices was extracted based on a cropping intensity mapping algorithm using MODIS Enhanced Vegetation Index （EVI） time series at 500-m spatial resolution and 8-day time intervals. Then the physical characteristics and landscape pattern of MCI trends were analyzed from 2000-2012. Results showed that MCI in Huang-Huai-Hai agricultural region has increased from 152% to 156% in the 12 years. Topography is a primary factor in determining more stable in hilly area than in plain area. An the spatial pattern dynamics of MCI, which is increase from 158% to 164% of MCI occurred irplain area while there was almost no change in hilly area with single cropping. The most active region of MCI change was the intersection zone between the hilly area and plain area. In spatial patterns, landscape of multiple cropping systems tended to be homogenized reflected by a reduction in the degree of fragmentation and an increase in the degree of concentration of cropland with the same cropping system.
基金supported by Consejo Nacional de Ciencia y Tecnología and the Mexican Space Agency[AEM-2017-01-292774]Instituto Politécnico Nacional[SIP-2018-1090,SIP-2020-1876]National Aeronautics and Space Administration[Terrestrial Hydrology Program-NNX16AQ24G].
文摘An Ensemble Kalman Filter(EnKF)-based assimilation algorithm was implemented to estimate root-zone soil moisture(RZSM)using a Soil-Vegetation-Atmosphere Transfer(SVAT)model during a complete growing season of corn in Central Mexico.Synthetic and field soil moisture(SM)observations and NASA SMAP SM retrievals were used to understand the effect of vertically spatial updates and uncertainties in meteorological forcings on RZSM estimates.Assimilation of RZSM every 3 days using SM observations at 4 depths lowered the averaged standard deviation(ASD)and the root mean square error(RMSE)by 60%and 50%,respectively,compared to the open-loop ASD.The assimilation of synthetic SM at the top 0-5 cm obtained RZSM closer to observations compared to THEXMEX-18 SM measurements and SMAP SM retrievals.Differences between EnKF estimates and SM observations and SMAP SM retrievals are mainly due to misrepresentation of vegetation conditions.The results improved SM estimates up to 10-cm depth using SMAP SM retrievals;however,additional studies are needed to improve SM at deeper layers.The implemented methodology can estimate SM at the top 10 cm of the soil every 3 days to mitigate the impact of the climate change on agricultural production over rainfed areas,particularly in developing countries.
基金the National Key Science and Technology Project(2004BA508B20)the National Natural Science Foundation of China(304710100)for their financial assistance.
文摘The regional agricultural system （RAS） can be divided into three subsystems： ecological, economic, and social. This article examines the use of the harmony coefficient （HC）, efficacy coefficient, rank of the harmony coefficient （RHC）, and its appraising index system within the RAS. The harmony coefficient function was developed using a variance coefficient and then applied to Ziyang District, Yiyang City in Hunan Province （ZYH）, China, as a test case. From 1995 to 2002, the HC of RAS increased from 0.2982 to 0.4826 and the RHC increased from 3 to 5, although the HC trend was an ＂n＂ type in general. This suggests that the HC was weakly maladjusted and the RAS was not harmonious. The HC of the ecological subsystem decreased from 0.3898 to 0.2850, and its RHC from 4 to 3, with the HC trend following the ＂n＂ type. For the economic subsystem, the HC value increased from 0.5767 to 0.7458 and the RHC from 6 to 8. However, the trend in HC for the economic subsystem was of the ＂U＂ type. The HC of the social subsystem increased slightly from 0.4948 to 0.4663, and the RHC did not change in value. From the HC trends, the HC curve of the economic subsystem is above the HC curve of ZYH and the HC curve of the ecological subsystem is below the HC curve of ZHY. Hence, the ZHY environment has been destroyed by economic development. Environment and social building should be regarded as important issues in the future and promoting RAS harmony development should be considered. The results of the theoretical analysis match fairly closely with reality, and suggest that the harmony theory is feasible in appraising RAS development phases.
基金Supported by the Key Research Subject of Economic Census of Xinjiang Production and Construction Corps(201004)the President Fund for Natural Science Project of Tarim University(TDZKSS09010)+1 种基金the Quality Project of Tarim University(TDZGKC09085)the Quality Project of Tarim University(TDZGTD09004)
文摘Agricultural input and output status in southern Xinjiang,China is introduced,such as lack of agricultural input,low level of agricultural modernization,excessive fertilizer use,serious damage of environment,shortage of water resources,tremendous pressure on ecological balance,insignificant economic and social benefits of agricultural production in southern Xinjiang,agriculture remaining a weak industry,agricultural economy as the economic subject of southern Xinjiang,and backward economic development of southern Xinjiang.Taking the Aksu area as an example,according to the input and output data in the years 2002-2007,input-output model about regional agriculture of the southern Xinjiang is established by principal component analysis.DPS software is used in the process of solving the model.Then,Eviews software is adopted to revise and test the model in order to analyze and evaluate the economic significance of the results obtained,and to make additional explanations of the relevant model.Since the agricultural economic output is seriously restricted in southern Xinjiang at present,the following countermeasures are put forward,such as adjusting the structure of agricultural land,improving the utilization ratio of land,increasing agricultural input,realizing agricultural modernization,rationally utilizing water resources,maintaining eco-environmental balance,enhancing the awareness of agricultural insurance,minimizing the risk and loss,taking the road of industrialization of characteristic agricultural products,and realizing the transfer of surplus labor force.
基金supported by the Natural Sci-ence Foundation of Jiangsu Province (Grant No. BK2005040)the MOHURD Program of China (Grant No. 06-R5-10).
文摘Regional agriculture is the basis of regional sustainable development, so sustainable regional agricultural development is essential to the sustainable development of the whole society and becomes the focus of global research. The classification of regional agricultural structure is the basic work of regional agriculture study. This paper constructs index system （27 indices） of regional agricultural structure types with the three big indices： natural resources, developmental level of the agro-economy, and agro-ecological conditions. This paper also endows weight to every sub-classification index by means of AHP and obtains the comprehensive evaluation value of the three types of indices with arithmetic average weight approach. The regional agricultural structure can be classified into eight types in accordance with this evaluation results. The empirical study of China shows that the 31 provinces （municipalities and autonomous regions） are of different agriculture structural types. Finally, countermeasures of sustainsable agricultural development are put forward for the different agriculture structure features.
基金Supported by the National Natural Science Foundation of China(41571167)
文摘In the paper, three farms of Jiansanjiang Farming Bureau and five villages in of Dayushu Town in Fujin county randomly were taken as data sources for the investigation of household behavior of reclamation and agricultural area under different land systems, and it can be concluded that the main content included production scale, arable land use structure, household behavior and economic benefits. By comparison and analysis, the advantages and disadvantages of reclamation and agricultural area can be found, which could provide references for agricultural land reform for achieving a more suitable socio-economic of efficient use and sustained and healthy development of agriculture.
文摘Significance of nitrous oxide in atmospheric chemistry is reviewed briefly. Background concentration of N2O at Wudaoliang in Qinghai Province of Western China has been measured by collecting gas samples and analysing them with electron capture-gas chromatography. The atmospheric concentration fluctuates in the range of 303-315 ppb with the mean value of 308 ppb. The emission rate of N2O in agriculture region of Northern China has been studied primarily. Fertilization, rain and temperature of soil appear conductible to N2O emission. The interactions between greenhouse effect and N2O emission have been discussed. The catalytic action of N2O in stratospheric ozone depletion processes and the effect of high N2O concentration on ozone depletion in stratosphere have been considered and discussed.
文摘The state support of the agriculture is increasing with the globalization of Russia, the need to shape level and instruments in accordance with the WTO requirements. For Russia, rational state support of agriculture is topical according to the domestic economic problems： insufficient financing in Russia, in the regions; degradation of production facilities; turnover acreage reduction; reduction in livestock; and according to the external economic factors： the accession to the WTO, the transition to the Common Economic Space, and subsequently, the Eurasian Economic Union, global change conditions in the global food market, an increase in the world population, increasing demand for food resources, a significant increase in food prices on world markets, the increased activity of Russian agricultural producers in the world markets of grain products; ensuring of economic stability systems, critical analysis of the tools and the effectiveness of economic policy. According to the IMF, the economic has slowed down despite the state support for agriculture should stay a priority in the government＇s economic policy, in the regions.
文摘Maize is one of our country quite important grain crops,its height output is an important pillar ensure that grain of our country is safe,if speedy science ascertaining that maize expediency area cultivating,it can provide the most reliable decision-making reference to jobs such as agricultural regionalization,crop layout,accurate agriculture of essence.The article carries out a maize cultivating expediency research make use of the minute RS and GIS means,it can guarantee the results is timeliness and scientificalness.
基金Sponsored by Key Support Program of the Youth Academic Researches of Universities and Colleges in Heilongjiang(1252G012)
文摘Based on the data of the second national land survey and GIS method, this paper takes Fujin City as a study area to refl ect the similarities and differences of settlement system characteristics between reclamation and agricultural region in Heilongjiang Province, in order to discover the effect of land system on structure of settlement system. The results are as follows:(1) In the aspect of the spatial distribution pattern, settlement systems of both reclamation and agricultural region show clustered distribution, but those in reclamation region are denser;(2) The settlement systems of reclamation and agricultural regions can be divided into 4 levels, and their settlement systems are not incompatible with the 3 distribution patterns proposed in the center place theory, and show completely different hierarchical orders;(3) The average scale of reclamation settlement is smaller than that of agricultural settlement, but the difference is much more signifi cant;(4) The settlement systems in reclamation and agricultural regions have some problems, such as high proportion of the mini-settlements, and unreasonable space network system. Some measures should be taken, such as accelerating the reconstruction of the settlement system, optimizing the layout of settlement network system and transportation network, and promoting the connection between settlement systems in reclamation and agricultural regions in near future.
基金the Scientific and Technological Innovation Team Project in Key Areas(2019CB004)the Water-Saving Irrigation Experiment Project(BTJSSY–201911)of Xinjiang Production and Construction Corps,China。
文摘To combat the problem of residual film pollution and ensure the sustainable development of agriculture in oasis areas,a field experiment was carried out in 2019 at the Wuyi Farm Corps Irrigation Center Test Station in Urumqi,Northwest China.Four types of biodegradable mulches,traditional plastic mulchs and a control group(bare land;referred to as CK)were compared,including a total of six different treatments.Effects of mulching on soil water and heat conditions as well as the yield and quality of processing tomatoes under drip irrigation were examined.In addition,a comparative analysis of economic benefits of biodegradable mulches was performed.Principal component analysis and gray correlation analysis were used to evaluate suitable mulching varieties for planting processing tomatoes under drip irrigation.Our results show that,compared with CK,biodegradable mulches and traditional plastic mulch have a similar effect on retaining soil moisture at the seedling stage but significantly increase soil moisture by 0.5%-1.5%and 1.5%-3.0%in the middle and late growth periods(P<0.050),respectively.The difference in the thermal insulation effect between biodegradable mulch and plastic mulch gradually reduces as the crop grows.Compared with plastic mulch,the average soil temperature at 5-20 cm depth under biodegradable mulches is significantly lowered by 2.04°C-3.52°C and 0.52°C-0.88°C(P<0.050)at the seedling stage and the full growth period,respectively,and the water use efficiency,average fruit yield,and production-investment ratio under biodegradable mulches were reduced by 0.89%-6.63%,3.39%-8.69%,and 0.51%-6.33%(P<0.050),respectively.The comprehensive evaluation analysis suggests that the black oxidized biological double-degradation ecological mulch made from eco-benign plastic is the optimal film type under the study condition.Therefore,from the perspective of sustainable development,biodegradable mulch is a competitive alternative to plastic mulch for large-scale tomato production under drip irrigation in the oasis.
基金funded by the Special Fund for AgroScientific Research in the Public Interest, China (201003014)
文摘Phosphorus（P） losses from agricultural soils contribute to eutrophication of surface waters. This field plot study investigated effects of rainfall regimes and P applications on P loss by surface runoff from rice（Oryza sativa L.） and wheat（Triticum aestivum L.） cropping systems in Lake Taihu region, China. The study was conducted on two types of paddy soils（Hydromorphic at Anzhen site, Wuxi City, and Degleyed at Xinzhuang site, Changshu City, Jiangsu Province） with different P status, and it covered 3 years with low, high and normal rainfall regimes. Four rates of mineral P fertilizer, i.e., no P（control）, 30 kg P ha^（–1） for rice and 20 kg P ha^（–1） for wheat（P_（30＋20））, 75 plus 40（P_（75＋40））, and 150 plus 80（P_（150＋80））, were applied as treatments. Runoff water from individual plots and runoff events was recorded and analyzed for total P and dissolved reactive P concentrations. Losses of total P and dissolved reactive P significantly increased with rainfall depth and P rates（P〈0.0001）. Annual total P losses ranged from 0.36–0.92 kg ha^–1 in control to 1.13–4.67 kg ha^–1 in P150＋80 at Anzhen, and correspondingly from 0.36–0.48 kg h^–1 to 1.26–1.88 kg ha^–1 at Xinzhuang, with 16–49% of total P as dissolved reactive P. In particular, large amounts of P were lost during heavy rainfall events that occurred shortly after P applications at Anzhen. On average of all P treatments, rice growing season constituted 37–86% of annual total P loss at Anzhen and 28–44% of that at Xinzhuang. In both crop seasons, P concentrations peaked in the first runoff events and decreased with time. During rice growing season, runoff P concentrations positively correlated（P〈0.0001） with P concentrations in field ponding water that was intentionally enclosed by construction of field bund. The relative high P loss during wheat growing season at Xinzhuang was due to high soil P status. In conclusion, P should be applied at rates balancing crop removal（20–30 kg P ha^–1 in this study） and at time excluding heavy rains. Moreover, irrigation and drainage water should be appropriately managed to reduce runoff P losses from rice-wheat cropping systems.
基金National Natural Science Foundation of China,No.41201176No.41171149No.41130748
文摘Identifying the problem regions and regional problems, and thus improving regional policies, are crucial for the sustainable development of various economic entities. The coordinated development of industrialization, informatization, urbanization and agricultural modernization（hereinafter referred to as ＂Sihua＂） is not only a practical need but an important strategic direction of integrating urban-rural development and regional development in recent China, and it also provides a significant perspective for identifying problem regions and regional problems so as to improve the regional policies. This study mainly aims to： firstly, establish a comprehensive evaluation index system so as to explore the spatial pattern of coordinated development of Sihua in China at prefecture level; secondly, to develop an evaluation criteria system to identify the problem regions and regional problems from the perspective of coordinated development of Sihua. This paper comes first in the scientific community to evaluate the coordinated development state of Sihua in China at prefecture level and identify the problem regions and regional problems from the perspective of Sihua development by quantitative analysis. This study may benefit the improvement of regional policies and thus contribute to the sustainable socio-economic development of China.
文摘Based on explicating the definition of ecotone, this paper discussed emphatically the distribution and features of joint zone between land and water, transition zone between mountains and plains, and intersection zone between agricultural and animal husbandry regions. The geographic environment of the three ecotones were evaluated, their developing tendency predicted and the corresponding measures to be taken in the 21st century pointed out.
