Sustainable use of natural resources is different from sustainable development. As the most important natural resource, sustainable use of land resource is the essential guarantee of sustainable development. The natur...Sustainable use of natural resources is different from sustainable development. As the most important natural resource, sustainable use of land resource is the essential guarantee of sustainable development. The nature of sustainable use of land resource is to retain the quantity and productivity of land resource from generation to generation.The evaluation of sustainable use of land resource is an important method to ensure land use to get onto the sustainable track. Furthermore, building index system is the key of the evaluation. In view of tendency of the evaluation indexes chosen so widely, the evaluation indexes should include only three kinds in the researches on the evaluation of sustainable use of land resource. The first is the stock and structure index of land resource, viz. Areas quantity structure of land resources. In China, it is especially paid attention to the per person index of land quantity and rate between cultivated land and farmland. The second is the productive index of land, which includes the productivity, potentiality, stability and renewal situation of land. The third is the sustained index of land environment. On the evaluation research of area level, we should lay particular emphasis on statistic indexes. With a case of Guangxi Zhuang Autonomous Region in China, the evaluation index system of sustainable land use in county area has been built in this thesis. Using the weighted average method to calculate the means of sustainable land use in each county, according to the land using situation, all counties in the autonomous region have been divided into three types. (1) Sustainable Pattern contains 18 counties, which have higher land resource productivity, stronger sustained abilities of land environment .The economic benefits of land using in these counties are obviously higher. These counties have gotten highly intensive farming, and they are all in the good circumstance. (2) Basically Sustained Pattern contains 48 counties, which productivity of land resource is of middle level. In part of counties and cities, the stock of land resource inclines to lower level, but their land using potentialities are still greater. Through changing land using pattern, these counties can rapidly enter in a good circumstance. (3) Critically Sustained Pattern contains 14 counties, which are mostly in the karst mountain areas. They have less stock of land resource, lower productivity and more extensive cultivation. The productivity of land renewing has been hindered, so it urgently need to be renovated. At last, the writers have explored the basic ways of sustainable use of land resource in Guangxi, China — (1) Retain the stock of land resource and strictly manage farmland uses. (2) Strengthen the value accounting of land resource, and control the farmland occupation of non agricultural construction. (3) Depend on technology advanced, optimize the land using structure, and promote the productive level. (4) Carry out land management all round, and improve the ecological environment of land resource. (5) Enhance evaluation researche and land monitoring, and promote the sustainable utilization level of land resource.展开更多
The countries of Central Asia are collectively known as the five "-stans": Uzbekistan, Kyrgyzstan, Turkmenistan, Tajikistan and Kazakhstan. In recent times, the Central Asian region has been affected by the ...The countries of Central Asia are collectively known as the five "-stans": Uzbekistan, Kyrgyzstan, Turkmenistan, Tajikistan and Kazakhstan. In recent times, the Central Asian region has been affected by the shrinkage of the Aral Sea, widespread desertification, soil salinization, biodiversity loss, frequent sand storms, and many other ecological disasters. This paper is a review article based upon the collection, identification and collation of previous studies of environmental changes and regional developments in Central Asia in the past 30 years. Most recent studies have reached a consensus that the temperature rise in Central Asia is occurring faster than the global average. This warming trend will not only result in a higher evaporation in the basin oases, but also to a significant retreat of glaciers in the mountainous areas. Water is the key to sustainable development in the arid and semi-arid regions in Central Asia. The uneven distribution, over consumption, and pollution of water resources in Central Asia have caused severe water supply problems, which have been affecting regional harmony and development for the past 30 years. The widespread and significant land use changes in the 1990 s could be used to improve our understanding of natural variability and human interaction in the region. There has been a positive trend of trans-border cooperation among the Central Asian countries in recent years. International attention has grown and research projects have been initiated to provide water and ecosystem protection in Central Asia. However, the agreements that have been reached might not be able to deliver practical action in time to prevent severe ecological disasters. Water management should be based on hydrographic borders and ministries should be able to make timely decisions without political intervention. Fully integrated management of water resources, land use and industrial development is essential in Central Asia. The ecological crisis should provide sufficient motivation to reach a consensus on unified water management throughout the region.展开更多
Water is the important resource to guarantee the existence and development of oases in arid areas. To improve the utilization efficiency of water resources in Manas River Basin, this paper investigated the trends and ...Water is the important resource to guarantee the existence and development of oases in arid areas. To improve the utilization efficiency of water resources in Manas River Basin, this paper investigated the trends and periods of runoff based on the runoff and climate data for the past 50 years. Subsequently, with the socioeconomic and water resources data, we studied a comprehensive evaluation on the water security in this area. The results indicated that the stream flows in the three hydrological stations of Hongshanzui, Kensiwat and Bajiahu have sig- nificantly increased and undergone abrupt changes, with periods of 18 and 20 years. According to assessment, water security in the Manas River Basin was at an unsafe level in 2008. In criterion layer, the ecological security index and the index of supply-demand situation are both at the relatively secure level; the quantity index and so- cioeconomic index of water resources are at the unsafe level and basic security level, respectively. Therefore, in order to achieve sustainable economic and social development within the Manas River Basin, it is vital to take a series of effective measures to improve the status of water security.展开更多
The study on the sustainable utilization of water resources of Jinan city is a research hotspot in the urban sustainable development field.How to use a scientific and rational evaluation index system to analyze the su...The study on the sustainable utilization of water resources of Jinan city is a research hotspot in the urban sustainable development field.How to use a scientific and rational evaluation index system to analyze the sustainable utilization of water resources of Jinan city and then guide the development and utilization of water resources becomes particularly important.Based on the theory of sustainable development this study introduces the method,basic steps and evaluation indexes of the assessment of the development and utilization of water resources.By systemic analyzing the exploitation and utilization standards of water resources and economy and society in Jinan city,the evaluation and index system of sustainable utilization of water resources in Jinan city can be constructed and index weight can be confirmed,and then,the standard of sustainable utilization of water resources in different years can be analyzed comparably.Thus,the deficiency of lack of reflection of coordination extent in water resources development standard,society and economy in traditional evaluation method is settled efficiently.The paper takes the sustainable utilization of water resources of Qingdao City in 2008 as the standard to compare and assess the water resources utilization in Jinan City.The paper also collects data of water resources in Jinan City from 2001 to 2007.The result indicates that evaluation method is of feasibility and it is effective to the implementation of sustainable utilization strategy water resources in Jinan City.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
The increasing world population has forced excessive chemical fertilizer and irrigation to complete the global food demand,deteriorating the water quality and nutrient losses.Short-term studies do not compile the evid...The increasing world population has forced excessive chemical fertilizer and irrigation to complete the global food demand,deteriorating the water quality and nutrient losses.Short-term studies do not compile the evidences;therefore,the study aimed to identify the effectiveness of reduced doses of inorganic fertilizer and water-saving practices,hence,a six-year experiment(2015-2020)was conducted in China to address the knowledge gap.The experimental treatments were:farmer accustomed fertilization used as control(525:180:30 kg NPK ha^(-1)),fertilizer decrement(450:150:15 kg NPK ha^(-1)),fertilizer decrement+water-saving irrigation(450:150:15 kg NPK ha^(-1)),application of organic and inorganic fertilizer+water-saving irrigation(375:120:0 kg NPK ha^(-1)+4.5 tones organic fertilizer ha^(-1)),and application of controlled-release fertilizer(80:120:15 kg NPK ha^(-1)).Each treatment was replicated thrice following a randomized complete block design.The results achieved herein showed that control has the highest losses in the six-year study for total nitrogen(225.97 mg L^(-1)),total soluble nitrogen(121.58 mg L^(-1)),nitrate nitrogen(0.93 mg L^(-1)),total phosphorus(0.57 mg L^(-1)),and total soluble phosphorus(0.57 mg L^(-1))respectively.Reduced fertilizer and water application improved crop nutrient uptake,nitrogen concentration was significantly enhanced with organic and inorganic fertilizer+water-saving irrigation,P concentration was increased with fertilizer decrement+water-saving irrigation,and K concentration was improved with fertilizer decrement+water-saving irrigation.Hence,this study concludes that reduced inorganic fertilizer dose combined with water-saving practices is significantly helpful in reducing nutrient leaching losses and improving nutrient uptake and water pollution.Further studies are needed to explore the impacts of reduced fertilization and water-saving irrigation on leaching losses.The benefits at different climatic conditions,soil types,and fertilizer types with application methods are also a research gap.展开更多
Our case study analyzed the proximity of previously mapped fractures in the aquifer matrix to 93 Florida panther (Puma concolor coryi) dens mapped from 2007-2016 in south Florida. Dens occurred in five counties (Colli...Our case study analyzed the proximity of previously mapped fractures in the aquifer matrix to 93 Florida panther (Puma concolor coryi) dens mapped from 2007-2016 in south Florida. Dens occurred in five counties (Collier = 77, Dade = 1, Hendry = 9, Lee = 5, and Monroe = 1) and three sub-basins of the Greater Everglades Basin (Big Cypress Swamp = 83, Caloosahatchee = 3, and Everglades = 7). Fractured aquifers occur worldwide, but are not the focus of habitat suitability studies, despite evidence that fractures influence plant species composition and density. Habitat alterations can occur many kilometers from the surface footprint of groundwater alterations in the regional Floridan aquifer system via preferential flow through fractures. Increased natural discharge from and recharge to the aquifer occur at fracture intersections. Greater induced recharge and habitat changes also may occur at fracture intersections. All dens were within 5 km of a previously mapped fracture;36% and 74% were within 1 km and 2 km, respectively, of those fractures;and 47%, 74%, and 90% of dens were within 2 km, 3.25 km and 5 km, respectively, from the nearest fracture intersection. Results suggest fractures influence the suitability and/or availability of habitat for panther dens, selection of den sites, and availability as well as abundance of high quality prey items essential for the nutritional demands of successfully rearing panther kittens in the wild. We recommend more detailed investigations of: a) vegetation characteristics near dens, b) groundwater alterations and cumulative impacts of those alterations associated with fractures in panther habitat (e.g., altered plant species composition and density), and c) influence of aquifer fractures in all habitats underlain by fractures.展开更多
The increasing challenges of pressure and ever-growing demands on limited resources in Nepal by diverse actors,land degradation,biodiversity loss and climate change require the rational use of land resources to sustai...The increasing challenges of pressure and ever-growing demands on limited resources in Nepal by diverse actors,land degradation,biodiversity loss and climate change require the rational use of land resources to sustain and enhance productivity and maintain resilient ecosystems for achieving the sustainable and efficient use of resources,taking into account biophysical and socioeconomic dimensions.Regarding this,Nepal Government has realized and taken initiation of scientific and sustainable land use zoning following the National Land Use Act 2019(2076 B.S.)to use land resources in practicable and sustainable manner.Using spatial information techniques such asZ-3 satellite image,remote sensing(RS),global positioning system(GPS)and geographic information system(GIS).Multicriteria decision making(MCDM)methods for acquiring spatial/temporal data,through expert judgment techniques based on field observation as well as laboratory analysis result,it was found that the soil nutrient status of,the municipality varied spatially and has pH with very high acidic to slightly alkaline but most of the soils are slightly acidic(39.58%).Majority of the soil are loam and sandy loam type with very low to high level of organic matter.Most of the municipal area is under medium range of organic matter.Nitrogen content ranges from very low to very high level as to same ranges of phosphorous(37.69%).Potassium level is also in very high to low as 37 percent land area has high level of potassium.Reclamation of acidic soil mainly in leachable soil is recommended with the proper management of Nitrogen with addition of organic matter is needed to manage for improving crop production.展开更多
小型农田水利工程的规划设计是提高农田灌溉效率和保障农业生产的重要环节。旨在探讨小型农田水利工程规划设计问题,并提出相应解决方案。首先,通过对小型农田水量需求进行调查和分析,确定了合理的灌溉水量。其次,针对农田的地形、土壤...小型农田水利工程的规划设计是提高农田灌溉效率和保障农业生产的重要环节。旨在探讨小型农田水利工程规划设计问题,并提出相应解决方案。首先,通过对小型农田水量需求进行调查和分析,确定了合理的灌溉水量。其次,针对农田的地形、土壤类型和作物种植情况,采用地理信息系统(Geographic Information System,GIS)技术进行数据采集和分析,以确定最佳的灌溉方式和灌溉设施布局。接着,结合农田的自然环境和社会经济条件,制定了适合农田的水资源管理和利用策略。最后,通过实地调研和模拟分析,验证了所提出的规划设计方案的可行性和有效性。研究结果表明,科学合理的小型农田水利工程规划设计可以提高农田的灌溉效率,减少水资源浪费,促进农业可持续发展。因此,该研究对于小型农田水利工程的规划设计具有一定的实践意义和指导价值。展开更多
The paper analyses the space time characteristics, primary causes and disastrous effects of the drying up of the Yellow River, and proposes the concept of "water resource bearing capacity (WRBC)", which refe...The paper analyses the space time characteristics, primary causes and disastrous effects of the drying up of the Yellow River, and proposes the concept of "water resource bearing capacity (WRBC)", which refers to the maximum bearing capacity of a river in meeting human demands for water on the precondition of sound recycling of the ecosystem. The concept encourages cautious human actions to save and conserve water resources.展开更多
文摘Sustainable use of natural resources is different from sustainable development. As the most important natural resource, sustainable use of land resource is the essential guarantee of sustainable development. The nature of sustainable use of land resource is to retain the quantity and productivity of land resource from generation to generation.The evaluation of sustainable use of land resource is an important method to ensure land use to get onto the sustainable track. Furthermore, building index system is the key of the evaluation. In view of tendency of the evaluation indexes chosen so widely, the evaluation indexes should include only three kinds in the researches on the evaluation of sustainable use of land resource. The first is the stock and structure index of land resource, viz. Areas quantity structure of land resources. In China, it is especially paid attention to the per person index of land quantity and rate between cultivated land and farmland. The second is the productive index of land, which includes the productivity, potentiality, stability and renewal situation of land. The third is the sustained index of land environment. On the evaluation research of area level, we should lay particular emphasis on statistic indexes. With a case of Guangxi Zhuang Autonomous Region in China, the evaluation index system of sustainable land use in county area has been built in this thesis. Using the weighted average method to calculate the means of sustainable land use in each county, according to the land using situation, all counties in the autonomous region have been divided into three types. (1) Sustainable Pattern contains 18 counties, which have higher land resource productivity, stronger sustained abilities of land environment .The economic benefits of land using in these counties are obviously higher. These counties have gotten highly intensive farming, and they are all in the good circumstance. (2) Basically Sustained Pattern contains 48 counties, which productivity of land resource is of middle level. In part of counties and cities, the stock of land resource inclines to lower level, but their land using potentialities are still greater. Through changing land using pattern, these counties can rapidly enter in a good circumstance. (3) Critically Sustained Pattern contains 14 counties, which are mostly in the karst mountain areas. They have less stock of land resource, lower productivity and more extensive cultivation. The productivity of land renewing has been hindered, so it urgently need to be renovated. At last, the writers have explored the basic ways of sustainable use of land resource in Guangxi, China — (1) Retain the stock of land resource and strictly manage farmland uses. (2) Strengthen the value accounting of land resource, and control the farmland occupation of non agricultural construction. (3) Depend on technology advanced, optimize the land using structure, and promote the productive level. (4) Carry out land management all round, and improve the ecological environment of land resource. (5) Enhance evaluation researche and land monitoring, and promote the sustainable utilization level of land resource.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences, Pan-Third Pole Environment Study for a Green Silk Road (XDA20060303)the Xinjiang Key Research and Development Program (2016B02017-4)+1 种基金the National Nature Science Foundation of China-United Nations Environment Programme (NSFC-UNEP, 41361140361)the ''High-level Talents Project'' (Y871171) of Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences
文摘The countries of Central Asia are collectively known as the five "-stans": Uzbekistan, Kyrgyzstan, Turkmenistan, Tajikistan and Kazakhstan. In recent times, the Central Asian region has been affected by the shrinkage of the Aral Sea, widespread desertification, soil salinization, biodiversity loss, frequent sand storms, and many other ecological disasters. This paper is a review article based upon the collection, identification and collation of previous studies of environmental changes and regional developments in Central Asia in the past 30 years. Most recent studies have reached a consensus that the temperature rise in Central Asia is occurring faster than the global average. This warming trend will not only result in a higher evaporation in the basin oases, but also to a significant retreat of glaciers in the mountainous areas. Water is the key to sustainable development in the arid and semi-arid regions in Central Asia. The uneven distribution, over consumption, and pollution of water resources in Central Asia have caused severe water supply problems, which have been affecting regional harmony and development for the past 30 years. The widespread and significant land use changes in the 1990 s could be used to improve our understanding of natural variability and human interaction in the region. There has been a positive trend of trans-border cooperation among the Central Asian countries in recent years. International attention has grown and research projects have been initiated to provide water and ecosystem protection in Central Asia. However, the agreements that have been reached might not be able to deliver practical action in time to prevent severe ecological disasters. Water management should be based on hydrographic borders and ministries should be able to make timely decisions without political intervention. Fully integrated management of water resources, land use and industrial development is essential in Central Asia. The ecological crisis should provide sufficient motivation to reach a consensus on unified water management throughout the region.
基金supported by the National Natural Science Foundation of China (41001066)the National Basic Research Program of China (Program 973) (2009CB421308)the Ministry of Water Resources’ Special Funds for Scientific Research on Public Causes (201101049)
文摘Water is the important resource to guarantee the existence and development of oases in arid areas. To improve the utilization efficiency of water resources in Manas River Basin, this paper investigated the trends and periods of runoff based on the runoff and climate data for the past 50 years. Subsequently, with the socioeconomic and water resources data, we studied a comprehensive evaluation on the water security in this area. The results indicated that the stream flows in the three hydrological stations of Hongshanzui, Kensiwat and Bajiahu have sig- nificantly increased and undergone abrupt changes, with periods of 18 and 20 years. According to assessment, water security in the Manas River Basin was at an unsafe level in 2008. In criterion layer, the ecological security index and the index of supply-demand situation are both at the relatively secure level; the quantity index and so- cioeconomic index of water resources are at the unsafe level and basic security level, respectively. Therefore, in order to achieve sustainable economic and social development within the Manas River Basin, it is vital to take a series of effective measures to improve the status of water security.
基金funded by the Project of the Department of Science and Technology of Shandong Province(Grant No.2007RKB180)
文摘The study on the sustainable utilization of water resources of Jinan city is a research hotspot in the urban sustainable development field.How to use a scientific and rational evaluation index system to analyze the sustainable utilization of water resources of Jinan city and then guide the development and utilization of water resources becomes particularly important.Based on the theory of sustainable development this study introduces the method,basic steps and evaluation indexes of the assessment of the development and utilization of water resources.By systemic analyzing the exploitation and utilization standards of water resources and economy and society in Jinan city,the evaluation and index system of sustainable utilization of water resources in Jinan city can be constructed and index weight can be confirmed,and then,the standard of sustainable utilization of water resources in different years can be analyzed comparably.Thus,the deficiency of lack of reflection of coordination extent in water resources development standard,society and economy in traditional evaluation method is settled efficiently.The paper takes the sustainable utilization of water resources of Qingdao City in 2008 as the standard to compare and assess the water resources utilization in Jinan City.The paper also collects data of water resources in Jinan City from 2001 to 2007.The result indicates that evaluation method is of feasibility and it is effective to the implementation of sustainable utilization strategy water resources in Jinan City.
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This study received funds from the National Natural Science Foundation of China[41361062]National Natural Science Foundation of China Joint Fund for Regional Innovation and Development[U20A20114]+1 种基金Natural Science Foundation of Ningxia Hui Autonomous Region[2022AAC03449]Station of Observation and Experiment National Agricultural Environment in Yinchuan,Ningxia,China[NAES091AE18].
文摘The increasing world population has forced excessive chemical fertilizer and irrigation to complete the global food demand,deteriorating the water quality and nutrient losses.Short-term studies do not compile the evidences;therefore,the study aimed to identify the effectiveness of reduced doses of inorganic fertilizer and water-saving practices,hence,a six-year experiment(2015-2020)was conducted in China to address the knowledge gap.The experimental treatments were:farmer accustomed fertilization used as control(525:180:30 kg NPK ha^(-1)),fertilizer decrement(450:150:15 kg NPK ha^(-1)),fertilizer decrement+water-saving irrigation(450:150:15 kg NPK ha^(-1)),application of organic and inorganic fertilizer+water-saving irrigation(375:120:0 kg NPK ha^(-1)+4.5 tones organic fertilizer ha^(-1)),and application of controlled-release fertilizer(80:120:15 kg NPK ha^(-1)).Each treatment was replicated thrice following a randomized complete block design.The results achieved herein showed that control has the highest losses in the six-year study for total nitrogen(225.97 mg L^(-1)),total soluble nitrogen(121.58 mg L^(-1)),nitrate nitrogen(0.93 mg L^(-1)),total phosphorus(0.57 mg L^(-1)),and total soluble phosphorus(0.57 mg L^(-1))respectively.Reduced fertilizer and water application improved crop nutrient uptake,nitrogen concentration was significantly enhanced with organic and inorganic fertilizer+water-saving irrigation,P concentration was increased with fertilizer decrement+water-saving irrigation,and K concentration was improved with fertilizer decrement+water-saving irrigation.Hence,this study concludes that reduced inorganic fertilizer dose combined with water-saving practices is significantly helpful in reducing nutrient leaching losses and improving nutrient uptake and water pollution.Further studies are needed to explore the impacts of reduced fertilization and water-saving irrigation on leaching losses.The benefits at different climatic conditions,soil types,and fertilizer types with application methods are also a research gap.
文摘Our case study analyzed the proximity of previously mapped fractures in the aquifer matrix to 93 Florida panther (Puma concolor coryi) dens mapped from 2007-2016 in south Florida. Dens occurred in five counties (Collier = 77, Dade = 1, Hendry = 9, Lee = 5, and Monroe = 1) and three sub-basins of the Greater Everglades Basin (Big Cypress Swamp = 83, Caloosahatchee = 3, and Everglades = 7). Fractured aquifers occur worldwide, but are not the focus of habitat suitability studies, despite evidence that fractures influence plant species composition and density. Habitat alterations can occur many kilometers from the surface footprint of groundwater alterations in the regional Floridan aquifer system via preferential flow through fractures. Increased natural discharge from and recharge to the aquifer occur at fracture intersections. Greater induced recharge and habitat changes also may occur at fracture intersections. All dens were within 5 km of a previously mapped fracture;36% and 74% were within 1 km and 2 km, respectively, of those fractures;and 47%, 74%, and 90% of dens were within 2 km, 3.25 km and 5 km, respectively, from the nearest fracture intersection. Results suggest fractures influence the suitability and/or availability of habitat for panther dens, selection of den sites, and availability as well as abundance of high quality prey items essential for the nutritional demands of successfully rearing panther kittens in the wild. We recommend more detailed investigations of: a) vegetation characteristics near dens, b) groundwater alterations and cumulative impacts of those alterations associated with fractures in panther habitat (e.g., altered plant species composition and density), and c) influence of aquifer fractures in all habitats underlain by fractures.
文摘The increasing challenges of pressure and ever-growing demands on limited resources in Nepal by diverse actors,land degradation,biodiversity loss and climate change require the rational use of land resources to sustain and enhance productivity and maintain resilient ecosystems for achieving the sustainable and efficient use of resources,taking into account biophysical and socioeconomic dimensions.Regarding this,Nepal Government has realized and taken initiation of scientific and sustainable land use zoning following the National Land Use Act 2019(2076 B.S.)to use land resources in practicable and sustainable manner.Using spatial information techniques such asZ-3 satellite image,remote sensing(RS),global positioning system(GPS)and geographic information system(GIS).Multicriteria decision making(MCDM)methods for acquiring spatial/temporal data,through expert judgment techniques based on field observation as well as laboratory analysis result,it was found that the soil nutrient status of,the municipality varied spatially and has pH with very high acidic to slightly alkaline but most of the soils are slightly acidic(39.58%).Majority of the soil are loam and sandy loam type with very low to high level of organic matter.Most of the municipal area is under medium range of organic matter.Nitrogen content ranges from very low to very high level as to same ranges of phosphorous(37.69%).Potassium level is also in very high to low as 37 percent land area has high level of potassium.Reclamation of acidic soil mainly in leachable soil is recommended with the proper management of Nitrogen with addition of organic matter is needed to manage for improving crop production.
文摘小型农田水利工程的规划设计是提高农田灌溉效率和保障农业生产的重要环节。旨在探讨小型农田水利工程规划设计问题,并提出相应解决方案。首先,通过对小型农田水量需求进行调查和分析,确定了合理的灌溉水量。其次,针对农田的地形、土壤类型和作物种植情况,采用地理信息系统(Geographic Information System,GIS)技术进行数据采集和分析,以确定最佳的灌溉方式和灌溉设施布局。接着,结合农田的自然环境和社会经济条件,制定了适合农田的水资源管理和利用策略。最后,通过实地调研和模拟分析,验证了所提出的规划设计方案的可行性和有效性。研究结果表明,科学合理的小型农田水利工程规划设计可以提高农田的灌溉效率,减少水资源浪费,促进农业可持续发展。因此,该研究对于小型农田水利工程的规划设计具有一定的实践意义和指导价值。
文摘The paper analyses the space time characteristics, primary causes and disastrous effects of the drying up of the Yellow River, and proposes the concept of "water resource bearing capacity (WRBC)", which refers to the maximum bearing capacity of a river in meeting human demands for water on the precondition of sound recycling of the ecosystem. The concept encourages cautious human actions to save and conserve water resources.