Hydrological,sediment,and bathymetric data of the Shashi Reach in the middle Yangtze River for the period of 1975-2018 were collected,and the characteristics of low water level changes and their impacts on utilization...Hydrological,sediment,and bathymetric data of the Shashi Reach in the middle Yangtze River for the period of 1975-2018 were collected,and the characteristics of low water level changes and their impacts on utilization of water depth for navigation were investigated.The results showed that,during the study period,the Shashi Reach riverbed was significantly scoured and incised,with cross-sectional profiles showing overall narrowing and deepening.This indicated a strong potential to improve the water depth of the channel.The analysis of the temporal variation of in-channel topographical features showed that the Taipingkou diara underwent siltation and erosion,with its head gradually scoured and relocated downstream after 2008,and the Sanbatan diara continued to shrink and migrate leftwards.Low water levels with the same flow rate over the study period decreased.For instance,from 2003 to 2020,the water level at the Shashi hydrological station decreased to 1.37 m with a flow rate of 6000 m^(3)/s.Furthermore,the designed minimum navigable water level of the Shashi Reach was approximately 2.11m lower than the recommended level.In terms of utilization of the channel water depth,continuous scouring of the river channel is expected to result in a reduction in discharge at the Taipingkou mouth,which will improve the water depth conditions of the channel during the dry season in the Shashi Reach.With several channel regulation projects,the 3.5-m depth of the Shashi Reach would basically be unobstructed.This promotes utilization of the shipping route from the Taipingkou south branch to the Sanbatan north branch as the main navigation channel during the dry season.Considering the factors of current water depth and the clear width limitation of the navigation hole at the Jingzhou Yangtze River Bridge,this route can still be favored as the main navigation channel with a 4.5-m depth during the dry season.展开更多
[Objectives]To explore the agricultural water resources utilization and management under the agricultural safety aim.[Methods]Fuzzy neural network algorithm was adopted.The evaluation model of agricultural water resou...[Objectives]To explore the agricultural water resources utilization and management under the agricultural safety aim.[Methods]Fuzzy neural network algorithm was adopted.The evaluation model of agricultural water resources utilization and management carrying capacity based on quantitative system was established.[Results]With the remarkable improvement of China's national income,great progress has been made in China's agricultural development.However,in the process of agricultural safety production,the problem of sustainable development has not been noticed,the problem of water resources exceeding the limit bearing capacity frequently occurs.[Conclusions]It is of great significance to effectively solve the problem of water resources utilization and management.In the feasibility test for the algorithm,further tests on various indicators show that the research is feasible.展开更多
The Yangtze River Basin’s water resource utilization efficiency(WUE)and scientific and technological innovation level(STI)are closely connected,and the comprehension of these relationships will help to improve WUE an...The Yangtze River Basin’s water resource utilization efficiency(WUE)and scientific and technological innovation level(STI)are closely connected,and the comprehension of these relationships will help to improve WUE and promote local economic growth and conservation of water.This study uses 19 provinces and regions along the Yangtze River’s mainstream from 2009 to 2019 as its research objects and uses a Vector Auto Regression(VAR)model to quantitatively evaluate the spatiotemporal evolution of the coupling coordination degree(CCD)between the two subsystems of WUE and STI.The findings show that:(1)Both the WUE and STI in the Yangtze River Basin showed an upward trend during the study period,but the STI effectively lagged behind the WUE;(2)The CCD of the two subsystems generally showed an upward trend,and the CCD of each province was improved to varying degrees,but the majority of regions did not develop a high-quality coordination stage;(3)The CCD of the two systems displayed apparent positive spatial autocorrelation in the spatial correlation pattern,and there were only two types:high-high(H-H)urbanization areas and low-low(L-L)urbanization areas;(4)The STI showed no obvious response to the impact of the WUE,while the WUE responded greatly to the STI,and both of them were highly dependent on themselves.Optimizing their interaction mechanisms should be the primary focus of high-quality development in the basin of the Yangtze River in the future.These results give the government an empirical basis to enhance the WUE and promote regional sustainable development.展开更多
This paper examines the current status of water resource management and conservation in China,along with strategies to address the water resource crisis.Given the current situation,the paper highlights issues such as ...This paper examines the current status of water resource management and conservation in China,along with strategies to address the water resource crisis.Given the current situation,the paper highlights issues such as incomplete legal mechanisms,limited environmental awareness among enterprises,and insufficient government investment.To ad-dress these challenges,the paper proposes a series of strategies,including improving the ecological environment,enhanc-ing production techniques,strengthening management systems,rationalizing water resource allocation,and implementing water-saving measures in both industrial and agricultural production.These strategies serve to achieve sustainable water resource management,reduce water pollution,and effectively tackle the pressing water resource issues faced in China currently.展开更多
Water scarcity has become a limiting factor for increasing crop production.Finding ways to improve water use efficiency(WUE)has become an urgent task for Chinese agriculture.To understand the response of different mai...Water scarcity has become a limiting factor for increasing crop production.Finding ways to improve water use efficiency(WUE)has become an urgent task for Chinese agriculture.To understand the response of different maize populations to changes in precipitation and the effects of changes in maize populations on WUE,this study conducted maize population experiments using maize hybrids with different plant types(compact and semi compact)and different planting densities at 25 locations across China.It was found that,as precipitation increased across different locations,maize grain yield first increased and then decreased,while WUE decreased significantly.Analyzing the relationship between WUE and the main climatic factors,this study found that WUE was significantly and negatively correlated with precipitation(R(daily mean precipitation)and R(accumulated precipitation))and was positively correlated with temperature(TM(daily mean maximum temperature),T_(M-m)(T_(m),daily mean minimum temperature)and GDD(growing degree days))and solar radiation(Ra(daily mean solar radiation)and Ra(accumulated solar radiation))over different growth periods.Significant differences in maize grain yield,WUE and precipitation were found at different planting densities.The population densities were ranked as follows according to maize grain yield and WUE based on the multi-site experiment data:60000 plants ha^(-1)(P_(2))>90000 plants ha^(-1)(P_(3))>30000 plants ha^(-1)(P_(1)).Further analysis showed that,as maize population increased,water consumption increased significantly while soil evaporation decreased significantly.Significant differences were found between the WUE of ZD958(compact type)and that of LD981(semi-compact type),as well as among the WUE values at different planting densities.In addition,choosing the optimum hybrid and planting density increased WUE by 21.70 and 14.92%,respectively,which showed that the hybrid played a more significant role than the planting density in improving WUE.Therefore,choosing drought-resistant hybrids could be more effective than increasing the planting density to increase maize grain yield and WUE in northern China.Comprehensive consideration of climatic impacts,drought-resistant hybrids(e.g.,ZD958)and planting density(e.g.,60000 plants ha^(-1))is an effective way to increase maize grain yield and WUE across different regions of China.展开更多
The reclaimed water that we can use in daily life accounts for as much as 35 %,but we do not give it enough concern.The authors focus on the design methods and approaches of green buildings,which refer to water saving...The reclaimed water that we can use in daily life accounts for as much as 35 %,but we do not give it enough concern.The authors focus on the design methods and approaches of green buildings,which refer to water saving and environmental protection.In this paper,the authors illustrate the generating channels of reclaimed water in architecture design:rainwater collection integration design,sewage zero discharge of reclaimed water reused by biological technology,and sponge yard,thereby protecting environment.展开更多
Available irrigation resources are becoming increasingly scarce in the North China Plain (NCP),and nitrogen-use efficiency of crop production is also relatively low.Thus,it is imperative to improve the water-use effic...Available irrigation resources are becoming increasingly scarce in the North China Plain (NCP),and nitrogen-use efficiency of crop production is also relatively low.Thus,it is imperative to improve the water-use efficiency (WUE) and nitrogen fertilizer productivity on the NCP.Here,we conducted a two-year field experiment to explore the effects of different irrigation amounts (S60,60 mm;S90,90 mm;S120,120 mm;S150,150 mm) and nitrogen application rates (150,195 and 240 kg ha^(–1);denoted as N1,N2 and N3,respectively) under micro-sprinkling with water and nitrogen combined on the grain yield(GY),yield components,leaf area index (LAI),flag leaf chlorophyll content,dry matter accumulation (DM),WUE,and nitrogen partial factor productivity (NPFP).The results indicated that the GY and NPFP increased significantly with increasing irrigation amount,but there was no significant difference between S120 and S150;WUE significantly increased first but then decreased with increasing irrigation and S120 achieved the highest WUE.The increase in nitrogen was beneficial to improving the GY and WUE in S60 and S90,while the excessive nitrogen application (N3) significantly reduced the GY and WUE in S120 and S150 compared with those in the N2 treatment.The NPFP significantly decreased with increasing nitrogen rate under the same irrigation treatments.The synchronous increase in spike number (SN) and 1 000-grain weight (TWG)was the main reason for the large increase in GY by micro-sprinkling with increasing irrigation,and the differences in SN and TGW between S120 and S150 were small.Under S60 and S90,the TGW increased with increasing nitrogen application,which enhanced the GY,while N2 achieved the highest TWG in S120 and S150.At the filling stage,the LAI increased with increasing irrigation,and greater amounts of irrigation significantly increased the chlorophyll content in the flag leaf,which was instrumental in increasing DM after anthesis and increasing the TGW.Micro-sprinkling with increased amounts of irrigation or excessive nitrogen application decreased the WUE mainly due to the increase in total water consumption (ET)and the small increase or decrease in GY.Moreover,the increase in irrigation increased the total nitrogen accumulation or contents (TNC) of plants at maturity and reduced the residual nitrate-nitrogen in the soil (SNC),which was conducive to the increase in NPFP,but there was no significant difference in TNC between S120 and S150.Under the same irrigation treatments,an increase in nitrogen application significantly increased the residual SNC and decreased the NPFP.Overall,micro-sprinkling with 120 mm of irrigation and a total nitrogen application of 195 kg ha^(–1) can lead to increases in GY,WUE and NPFP on the NCP.展开更多
On the basis of analyzing the concurrency of water resource shortage and flood disasters in Chinese cities, this paper proposed the application of natural water drainage mechanism, and introduction of rainwater garden...On the basis of analyzing the concurrency of water resource shortage and flood disasters in Chinese cities, this paper proposed the application of natural water drainage mechanism, and introduction of rainwater garden into the urban landscape architecture design. The drainage ways of green streets including rainwater garden were elaborated, and it was proposed that roadside green belts can be used to save rainwater, realize the resource utilization of rainwater, to deal with the concurrency of drought and food in Chinese cities.展开更多
The Tarim River is a typical inland river in arid area without runoff yield of itself, and water resources are all supplied by its headstreams. The method of time series analysis is applied to annual runoff series of ...The Tarim River is a typical inland river in arid area without runoff yield of itself, and water resources are all supplied by its headstreams. The method of time series analysis is applied to annual runoff series of three headstreams, namely the Aksu River, Yarkant River and Hotan River to analyze their dynamic variations. A model is established to estimate water consumption in the headstream areas. Quantitative results indicate that both total annual runoff of headstreams and water consumption in the headstream areas have an increasing trend. The dynamic trends of annual runoff of hydrologic stations along the mainstream of the Tarim River are also presented to estimate the intermittence drying-up time at each station. Water consumption model of the mainstream area is used to analyze the characteristics of water consumption in the upper and middle reaches. It is shown that water consumption in each river reach of the mainstream decreases with the decrement of inflow and increases with human activities.展开更多
This study uses geographically weighted regression to determine the spatial distribution of the effective utilization coefficient of irrigation water in Zhejiang Province,China,owing to the influences of spatial attri...This study uses geographically weighted regression to determine the spatial distribution of the effective utilization coefficient of irrigation water in Zhejiang Province,China,owing to the influences of spatial attributes on the irrigation efficiency.The sample set of this study comprised 165 agricultural test sites.A multivariate linear regression model and a geographically weighted regression model were established using the effective utilization coefficient of agricultural irrigation water as the dependent variable in addition to a suite of independent variables,including the actual irrigation area,the percentage of farmland using water-saving irrigation,the type of irrigation area,the net water consumption per mu,the water intake method,the terrain slope,and the soil field capacity.Results revealed a positive spatial correlation and noticeable agglomeration features in the effective utilization coefficient of irrigation water in Zhejiang Province.The geographically weighted regression model performed better in terms of fit and prediction accuracy than the multivariate linear regression model.The obtained findings confirm the suitability of the geographically weighted regression model for determining the spatial distribution of the effective utilization coefficient of irrigation water in Zhejiang,and offer a new approach on a regional scale.展开更多
The loessal hill region in southern Ningxia is a semiarid and severe eroded area with developed agriculture and animal husbandry. It has long been an argument whether there might be more potentiality of farming and wh...The loessal hill region in southern Ningxia is a semiarid and severe eroded area with developed agriculture and animal husbandry. It has long been an argument whether there might be more potentiality of farming and whether food production can be sustained at a level of local sufficiency.展开更多
Winter wheat and summer maize were planted from 2015-2017 to study the effects of different rotational tillage patterns on soil physicochemical properties,crop yield,water content,and fertilizer utilization.The tillag...Winter wheat and summer maize were planted from 2015-2017 to study the effects of different rotational tillage patterns on soil physicochemical properties,crop yield,water content,and fertilizer utilization.The tillage treatments were designed as wheat subsoiling-maize no tillage(WS-MN),wheat rotary tillage-maize subsoiling(WR-MS),wheat subsoiling-maize subsoiling(WS-MS),and conventional wheat rotary tillage-maize no tillage(WR-MN)as a control.Among the four treatments,WS-MN and WR-MS were single-season subsoiling treatments,and WS-MS was a two-season subsoiling treatment.The average soil bulk density decreased by 7.6%in the single-and double-season subsoiling groups compared to the WR-MN group,and the total porosity and noncapillary porosity increased by 10.7%and 12.2%,respectively.Single-or double-season subsoiling treatment was not conducive to water storage in the 0-20 cm soil layer but increased the water content of the 20-140 cm soil layer,and the average soil water content of the 0-140 cm layer was increased by 11.6%in the two-growing season treatment groups compared with the WR-MN group.In WS-MS and WS-MN groups compared with the WR-MN group,the soil ammonium nitrogen content was increased by an average of 18.6%in 0-20 cm soil and 16.8%in 20-100 cm soil;soil nitrate-nitrogen content was decreased by 13.5%in 0-100 cm soil;total organic carbon and microbial carbon contents in the 15-30 cm soil were increased by 18.1%and 12.7%,respectively;and soil urease,catalase,and alkaline phosphatase activities were increased by 46.1%,15.2%,and 23.1%,respectively.Annual crop yield and water use efficiency increased by 8.9%and 15.0%,respectively,in both the single-and double-season subsoiling treatment groups.This study demonstrated the advantages of subsoiling tillage and suggested that it is suitable for crop cultivation in the Haihe Plain,China.展开更多
Introduction:Arid area is an important base for human settlement,however,long and drastic human activities have altered the drainage patterns in the arid watersheds significantly,causing serious ecological consequence...Introduction:Arid area is an important base for human settlement,however,long and drastic human activities have altered the drainage patterns in the arid watersheds significantly,causing serious ecological consequences.This study,through a case study of the Minqin Basin,a microcosm of the artificial oases in the arid northwest China,used the multitypes of data to recover the spatial distribution of human settlement and drainage patterns during historical period and analyze the relationship between them over the past 2000 years.Outcomes:Before the Han Dynasty(121 BC),the utilization of water resources in the Minqin Basin was in the primitive stage and the drainage pattern maintained the natural state.From the Han(121 BC-220)to the Wei-Jin Dynasties(220-316),the utilization of water resources intensified unprecedentedly,but the natural shape of the river systems was still maintained.In the following 1,000 years or so,the drainage pattern was in the state of“following its own course”due to the small human population.In the Ming Dynasty(1368-1644),with the alteration of the main rivers,the water resource utilization increased obviously,but the human reclamations were mainly confined to the southern part of the basin.In the Qing Dynasty(1644-1911),the reclamation of the Liulin Lake area significantly changed the drainage patterns,resulted in the drastically northward expansion of human settlement.Since the foundation of the People’s Republic of China(PRC)in 1949,the artificial water system completely replaced the natural water system and intensified the ecological problems in the basin.Discussion:The changes over the past 2000 years show the drastic impacts of human activities on the alterations of the drainage patterns and related ecological problems in the arid Northwest China.Conclusion:Rehabilitation of such ecological impairments requires both ecological restoration projects and changes in human paradigm and behavior over multiple temporal and spatial scales.展开更多
基金supported by the National Key Research and Development Program of China(Grant No.2018YFB 1600400)the National Natural Science Foundation of China(Grants No.51779184 and 51809131)+1 种基金the Fundamental Research Funds for Central Welfare Research Institutes(Grants No.TKS20200404 and TKS 190406)the Special Scientific Research Project of Changjiang Waterway Regulation(Grants No.SXHXGZ-2020-4,SXHXGZ-2022-1,and QD20190608-4).
文摘Hydrological,sediment,and bathymetric data of the Shashi Reach in the middle Yangtze River for the period of 1975-2018 were collected,and the characteristics of low water level changes and their impacts on utilization of water depth for navigation were investigated.The results showed that,during the study period,the Shashi Reach riverbed was significantly scoured and incised,with cross-sectional profiles showing overall narrowing and deepening.This indicated a strong potential to improve the water depth of the channel.The analysis of the temporal variation of in-channel topographical features showed that the Taipingkou diara underwent siltation and erosion,with its head gradually scoured and relocated downstream after 2008,and the Sanbatan diara continued to shrink and migrate leftwards.Low water levels with the same flow rate over the study period decreased.For instance,from 2003 to 2020,the water level at the Shashi hydrological station decreased to 1.37 m with a flow rate of 6000 m^(3)/s.Furthermore,the designed minimum navigable water level of the Shashi Reach was approximately 2.11m lower than the recommended level.In terms of utilization of the channel water depth,continuous scouring of the river channel is expected to result in a reduction in discharge at the Taipingkou mouth,which will improve the water depth conditions of the channel during the dry season in the Shashi Reach.With several channel regulation projects,the 3.5-m depth of the Shashi Reach would basically be unobstructed.This promotes utilization of the shipping route from the Taipingkou south branch to the Sanbatan north branch as the main navigation channel during the dry season.Considering the factors of current water depth and the clear width limitation of the navigation hole at the Jingzhou Yangtze River Bridge,this route can still be favored as the main navigation channel with a 4.5-m depth during the dry season.
基金Supported by Special Scientific Research Program of Shaanxi Provincial Department of Education"Study on the Development of Farmer Water Use Cooperative Organizations from the Dual Perspectives of Social Capital and Organizational Structure"(13YJC790135)Project of Social Science Foundation of Shaanxi Province"Study on Development of Farmer Water Use Cooperative Organization in Guanzhong Irrigation Area Based on the Withdrawal Behavior of Members"(2016D026)Special Scientific Research Fund Project of Xianyang Normal University"Study on Member Heterogeneity and the Governance of Farmers Fund Mutual Aid Organizations"(14XYK056).
文摘[Objectives]To explore the agricultural water resources utilization and management under the agricultural safety aim.[Methods]Fuzzy neural network algorithm was adopted.The evaluation model of agricultural water resources utilization and management carrying capacity based on quantitative system was established.[Results]With the remarkable improvement of China's national income,great progress has been made in China's agricultural development.However,in the process of agricultural safety production,the problem of sustainable development has not been noticed,the problem of water resources exceeding the limit bearing capacity frequently occurs.[Conclusions]It is of great significance to effectively solve the problem of water resources utilization and management.In the feasibility test for the algorithm,further tests on various indicators show that the research is feasible.
基金funded by the Humanities and Social Science Research Project of Chongqing Education Commission(23SKJD111)Science and Technology Research Project of Chongqing Education Commission(KJQN202101122 and KJQN201904002)+6 种基金Project of Chongqing Higher Education Association(CQGJ21B057)Chongqing Graduate Education Teaching Reform Research Project(yjg223121)Chongqing Higher Education Teaching Reform Research Project(233337)Higher Education Research Project,Chongqing University of Technology(2022ZD01)Annual project of the“14th Five-Year Plan”for National Business Education in 2022(SKKT-22015)Party Building and Ideological and Political Project,Chongqing University of Technology(2022DJ307)Chongqing University of Technology Undergraduate Education and Teaching Reform Research Project(2021YB21).
文摘The Yangtze River Basin’s water resource utilization efficiency(WUE)and scientific and technological innovation level(STI)are closely connected,and the comprehension of these relationships will help to improve WUE and promote local economic growth and conservation of water.This study uses 19 provinces and regions along the Yangtze River’s mainstream from 2009 to 2019 as its research objects and uses a Vector Auto Regression(VAR)model to quantitatively evaluate the spatiotemporal evolution of the coupling coordination degree(CCD)between the two subsystems of WUE and STI.The findings show that:(1)Both the WUE and STI in the Yangtze River Basin showed an upward trend during the study period,but the STI effectively lagged behind the WUE;(2)The CCD of the two subsystems generally showed an upward trend,and the CCD of each province was improved to varying degrees,but the majority of regions did not develop a high-quality coordination stage;(3)The CCD of the two systems displayed apparent positive spatial autocorrelation in the spatial correlation pattern,and there were only two types:high-high(H-H)urbanization areas and low-low(L-L)urbanization areas;(4)The STI showed no obvious response to the impact of the WUE,while the WUE responded greatly to the STI,and both of them were highly dependent on themselves.Optimizing their interaction mechanisms should be the primary focus of high-quality development in the basin of the Yangtze River in the future.These results give the government an empirical basis to enhance the WUE and promote regional sustainable development.
文摘This paper examines the current status of water resource management and conservation in China,along with strategies to address the water resource crisis.Given the current situation,the paper highlights issues such as incomplete legal mechanisms,limited environmental awareness among enterprises,and insufficient government investment.To ad-dress these challenges,the paper proposes a series of strategies,including improving the ecological environment,enhanc-ing production techniques,strengthening management systems,rationalizing water resource allocation,and implementing water-saving measures in both industrial and agricultural production.These strategies serve to achieve sustainable water resource management,reduce water pollution,and effectively tackle the pressing water resource issues faced in China currently.
基金the National Key Research and Development Program of China(2016YFD0300106)the National Natural Science Foundation of China(31601247).
文摘Water scarcity has become a limiting factor for increasing crop production.Finding ways to improve water use efficiency(WUE)has become an urgent task for Chinese agriculture.To understand the response of different maize populations to changes in precipitation and the effects of changes in maize populations on WUE,this study conducted maize population experiments using maize hybrids with different plant types(compact and semi compact)and different planting densities at 25 locations across China.It was found that,as precipitation increased across different locations,maize grain yield first increased and then decreased,while WUE decreased significantly.Analyzing the relationship between WUE and the main climatic factors,this study found that WUE was significantly and negatively correlated with precipitation(R(daily mean precipitation)and R(accumulated precipitation))and was positively correlated with temperature(TM(daily mean maximum temperature),T_(M-m)(T_(m),daily mean minimum temperature)and GDD(growing degree days))and solar radiation(Ra(daily mean solar radiation)and Ra(accumulated solar radiation))over different growth periods.Significant differences in maize grain yield,WUE and precipitation were found at different planting densities.The population densities were ranked as follows according to maize grain yield and WUE based on the multi-site experiment data:60000 plants ha^(-1)(P_(2))>90000 plants ha^(-1)(P_(3))>30000 plants ha^(-1)(P_(1)).Further analysis showed that,as maize population increased,water consumption increased significantly while soil evaporation decreased significantly.Significant differences were found between the WUE of ZD958(compact type)and that of LD981(semi-compact type),as well as among the WUE values at different planting densities.In addition,choosing the optimum hybrid and planting density increased WUE by 21.70 and 14.92%,respectively,which showed that the hybrid played a more significant role than the planting density in improving WUE.Therefore,choosing drought-resistant hybrids could be more effective than increasing the planting density to increase maize grain yield and WUE in northern China.Comprehensive consideration of climatic impacts,drought-resistant hybrids(e.g.,ZD958)and planting density(e.g.,60000 plants ha^(-1))is an effective way to increase maize grain yield and WUE across different regions of China.
基金Sponsored by Science and Technology Support Plan Project in"Twelfthth Five-year"Period(2014BAL06B02)
文摘The reclaimed water that we can use in daily life accounts for as much as 35 %,but we do not give it enough concern.The authors focus on the design methods and approaches of green buildings,which refer to water saving and environmental protection.In this paper,the authors illustrate the generating channels of reclaimed water in architecture design:rainwater collection integration design,sewage zero discharge of reclaimed water reused by biological technology,and sponge yard,thereby protecting environment.
基金funded by the National Key Research and Development Program of China(2016YFD0300105 and 2016YFD0300401)the National Natural Science Foundation of China(31871563)the earmarked fund for China Agriculture Research System(CARS-3)。
文摘Available irrigation resources are becoming increasingly scarce in the North China Plain (NCP),and nitrogen-use efficiency of crop production is also relatively low.Thus,it is imperative to improve the water-use efficiency (WUE) and nitrogen fertilizer productivity on the NCP.Here,we conducted a two-year field experiment to explore the effects of different irrigation amounts (S60,60 mm;S90,90 mm;S120,120 mm;S150,150 mm) and nitrogen application rates (150,195 and 240 kg ha^(–1);denoted as N1,N2 and N3,respectively) under micro-sprinkling with water and nitrogen combined on the grain yield(GY),yield components,leaf area index (LAI),flag leaf chlorophyll content,dry matter accumulation (DM),WUE,and nitrogen partial factor productivity (NPFP).The results indicated that the GY and NPFP increased significantly with increasing irrigation amount,but there was no significant difference between S120 and S150;WUE significantly increased first but then decreased with increasing irrigation and S120 achieved the highest WUE.The increase in nitrogen was beneficial to improving the GY and WUE in S60 and S90,while the excessive nitrogen application (N3) significantly reduced the GY and WUE in S120 and S150 compared with those in the N2 treatment.The NPFP significantly decreased with increasing nitrogen rate under the same irrigation treatments.The synchronous increase in spike number (SN) and 1 000-grain weight (TWG)was the main reason for the large increase in GY by micro-sprinkling with increasing irrigation,and the differences in SN and TGW between S120 and S150 were small.Under S60 and S90,the TGW increased with increasing nitrogen application,which enhanced the GY,while N2 achieved the highest TWG in S120 and S150.At the filling stage,the LAI increased with increasing irrigation,and greater amounts of irrigation significantly increased the chlorophyll content in the flag leaf,which was instrumental in increasing DM after anthesis and increasing the TGW.Micro-sprinkling with increased amounts of irrigation or excessive nitrogen application decreased the WUE mainly due to the increase in total water consumption (ET)and the small increase or decrease in GY.Moreover,the increase in irrigation increased the total nitrogen accumulation or contents (TNC) of plants at maturity and reduced the residual nitrate-nitrogen in the soil (SNC),which was conducive to the increase in NPFP,but there was no significant difference in TNC between S120 and S150.Under the same irrigation treatments,an increase in nitrogen application significantly increased the residual SNC and decreased the NPFP.Overall,micro-sprinkling with 120 mm of irrigation and a total nitrogen application of 195 kg ha^(–1) can lead to increases in GY,WUE and NPFP on the NCP.
基金Sponsored by"Twelfth Five-year Plan"of Jiangxi Provincial Social Sciences Program(14SH05)
文摘On the basis of analyzing the concurrency of water resource shortage and flood disasters in Chinese cities, this paper proposed the application of natural water drainage mechanism, and introduction of rainwater garden into the urban landscape architecture design. The drainage ways of green streets including rainwater garden were elaborated, and it was proposed that roadside green belts can be used to save rainwater, realize the resource utilization of rainwater, to deal with the concurrency of drought and food in Chinese cities.
基金This work was supported by State Key Project of the 9th Five-Year Plan (Grant No. 96-912-02-02) the Special Funds for State Major Basic Research Project (Grant No. G1999043500).
文摘The Tarim River is a typical inland river in arid area without runoff yield of itself, and water resources are all supplied by its headstreams. The method of time series analysis is applied to annual runoff series of three headstreams, namely the Aksu River, Yarkant River and Hotan River to analyze their dynamic variations. A model is established to estimate water consumption in the headstream areas. Quantitative results indicate that both total annual runoff of headstreams and water consumption in the headstream areas have an increasing trend. The dynamic trends of annual runoff of hydrologic stations along the mainstream of the Tarim River are also presented to estimate the intermittence drying-up time at each station. Water consumption model of the mainstream area is used to analyze the characteristics of water consumption in the upper and middle reaches. It is shown that water consumption in each river reach of the mainstream decreases with the decrement of inflow and increases with human activities.
基金This study was supported by the National Key R&D Program of China(Nos.2016YFC0401005 and 2016YFA0601703)the National Natural Science Foundation of China(Grant Nos.42075191,92047203 and 91847301)Nanjing Hydraulic Research Institute Fund(No.Y520009).We thank Chinese Academy of Meteorological Sciences for providing monitoring data of the study area.
文摘This study uses geographically weighted regression to determine the spatial distribution of the effective utilization coefficient of irrigation water in Zhejiang Province,China,owing to the influences of spatial attributes on the irrigation efficiency.The sample set of this study comprised 165 agricultural test sites.A multivariate linear regression model and a geographically weighted regression model were established using the effective utilization coefficient of agricultural irrigation water as the dependent variable in addition to a suite of independent variables,including the actual irrigation area,the percentage of farmland using water-saving irrigation,the type of irrigation area,the net water consumption per mu,the water intake method,the terrain slope,and the soil field capacity.Results revealed a positive spatial correlation and noticeable agglomeration features in the effective utilization coefficient of irrigation water in Zhejiang Province.The geographically weighted regression model performed better in terms of fit and prediction accuracy than the multivariate linear regression model.The obtained findings confirm the suitability of the geographically weighted regression model for determining the spatial distribution of the effective utilization coefficient of irrigation water in Zhejiang,and offer a new approach on a regional scale.
文摘The loessal hill region in southern Ningxia is a semiarid and severe eroded area with developed agriculture and animal husbandry. It has long been an argument whether there might be more potentiality of farming and whether food production can be sustained at a level of local sufficiency.
基金the Key R&D projects in Hebei Province(Grant No.20326407D)National Key Research and Development Project(Grant No.2017YFD0300906)National Science and Technology Support Project(Grant No.2012BAD04B06).
文摘Winter wheat and summer maize were planted from 2015-2017 to study the effects of different rotational tillage patterns on soil physicochemical properties,crop yield,water content,and fertilizer utilization.The tillage treatments were designed as wheat subsoiling-maize no tillage(WS-MN),wheat rotary tillage-maize subsoiling(WR-MS),wheat subsoiling-maize subsoiling(WS-MS),and conventional wheat rotary tillage-maize no tillage(WR-MN)as a control.Among the four treatments,WS-MN and WR-MS were single-season subsoiling treatments,and WS-MS was a two-season subsoiling treatment.The average soil bulk density decreased by 7.6%in the single-and double-season subsoiling groups compared to the WR-MN group,and the total porosity and noncapillary porosity increased by 10.7%and 12.2%,respectively.Single-or double-season subsoiling treatment was not conducive to water storage in the 0-20 cm soil layer but increased the water content of the 20-140 cm soil layer,and the average soil water content of the 0-140 cm layer was increased by 11.6%in the two-growing season treatment groups compared with the WR-MN group.In WS-MS and WS-MN groups compared with the WR-MN group,the soil ammonium nitrogen content was increased by an average of 18.6%in 0-20 cm soil and 16.8%in 20-100 cm soil;soil nitrate-nitrogen content was decreased by 13.5%in 0-100 cm soil;total organic carbon and microbial carbon contents in the 15-30 cm soil were increased by 18.1%and 12.7%,respectively;and soil urease,catalase,and alkaline phosphatase activities were increased by 46.1%,15.2%,and 23.1%,respectively.Annual crop yield and water use efficiency increased by 8.9%and 15.0%,respectively,in both the single-and double-season subsoiling treatment groups.This study demonstrated the advantages of subsoiling tillage and suggested that it is suitable for crop cultivation in the Haihe Plain,China.
基金This study was partially supported by Natural Science Foundation of China(NSFC Grants:41471163,41530752,91025010,and 40401060).
文摘Introduction:Arid area is an important base for human settlement,however,long and drastic human activities have altered the drainage patterns in the arid watersheds significantly,causing serious ecological consequences.This study,through a case study of the Minqin Basin,a microcosm of the artificial oases in the arid northwest China,used the multitypes of data to recover the spatial distribution of human settlement and drainage patterns during historical period and analyze the relationship between them over the past 2000 years.Outcomes:Before the Han Dynasty(121 BC),the utilization of water resources in the Minqin Basin was in the primitive stage and the drainage pattern maintained the natural state.From the Han(121 BC-220)to the Wei-Jin Dynasties(220-316),the utilization of water resources intensified unprecedentedly,but the natural shape of the river systems was still maintained.In the following 1,000 years or so,the drainage pattern was in the state of“following its own course”due to the small human population.In the Ming Dynasty(1368-1644),with the alteration of the main rivers,the water resource utilization increased obviously,but the human reclamations were mainly confined to the southern part of the basin.In the Qing Dynasty(1644-1911),the reclamation of the Liulin Lake area significantly changed the drainage patterns,resulted in the drastically northward expansion of human settlement.Since the foundation of the People’s Republic of China(PRC)in 1949,the artificial water system completely replaced the natural water system and intensified the ecological problems in the basin.Discussion:The changes over the past 2000 years show the drastic impacts of human activities on the alterations of the drainage patterns and related ecological problems in the arid Northwest China.Conclusion:Rehabilitation of such ecological impairments requires both ecological restoration projects and changes in human paradigm and behavior over multiple temporal and spatial scales.