共查询到19条相似文献，搜索用时 171 毫秒
1.
控制中国非点源污染的生物经济学战略 总被引：4，自引：0，他引：4
While non-point pollution from agriculture has become an increasingly serious problem in China, some progress has been made in studying the causal biophysical processes. However, few studies have assessed the economic consequences of non-point pollution in China or the policy options that could be employed to combat it. In this work a sustainable strategy to control non-point pollution from crop production, which involved taxing excessive inputs of irrigation water and fertilizer, was proposed. The approach taken to assess these measures combined biophysical and economic models,having a trade-off between economic returns and an improved environment. A proven and practical spatially referenced water and nutrient management model was used to determine the quantities of excessive irrigation water and fertilizer for specific soil and land use. Also, a set of indicators were proposed for evaluating the effects of agricultural economic output and agricultural practices on the environment. 相似文献
2.
China is now the world＇s largest producer and user of industrial fertilizers and manures. Consequently China plays a substantial role in global N cycle dynamics and in man＇s disruption of the nitrogen cycle though there are still significant uncertainties about the size and importance of emission and leaching rates. A major cause of China＇s global role is the overuse of nitrogen fertilizers, which is most serious with intensive vegetable production where application rates can be up to 50% greater than crop needs, but is also a problem with wheat, rice and maize. China＇s overuse of nitrogen fertiliser over the past 10-20 years has resulted in non-point source （NPS） pollution from crop production becoming a major cause of water pollution, and the situation is projected to get worse. In contrast, water pollution from point sources such as intensive livestock production and urban or industrial development is being brought more under control. The consequences for air pollution are equally serious. Emissions of nitrous oxide from fertilizers and manures may be so large that China could be responsible for 25-30% of global emissions of this damaging greenhouse gas and of the global warming resulting from it. The main national and local issues relate particularly to low fertilizer use efficiency and the losses of ammonia and NOx that lead to acid precipitation, and leaching and run-off losses that result in high nitrate levels in groundwater and eutrophication of rivers and lakes. The reasons why farmers overuse nitrogen fertilizer are complex and not fully understood. They involve agro-climate differences between provinces and counties, farming systems and farm income structures. Although there is a wide range of institutional and technological improvements that can greatly reduce this overuse rapid progress in reducing NPS is unlikely. 相似文献
3.
作物种植导致的非点源污染: 全球性、地域性以及民族性的问题 总被引：4，自引：1，他引：4
China is now the world's largest producer and user of industrial fertilizers and manures. Consequently China plays a substantial role in global N cycle dynamics and in man's disruption of the nitrogen cycle though there are still significant uncertainties about the size and importance of emission and leaching rates. A major cause of China's global role is the overuse of nitrogen fertilizers, which is most serious with intensive vegetable production where application rates can be up to 50% greater than crop needs, but is also a problem with wheat, rice and maize.China's overuse of nitrogen fertiliser over the past 10-20 years has resulted in non-point source (NPS) pollution from crop production becoming a major cause of water pollution, and the situation is projected to get worse. In contrast, water pollution from point sources such as intensive livestock production and urban or industrial development is being brought more under control. The consequences for air pollution are equally serious. Emissions of nitrous oxide from fertilizers and manures may be so large that China could be responsible for 25-30% of global emissions of this damaging greenhouse gas and of the global warming resulting from it. The main national and local issues relate particularly to low fertilizer use efficiency and the losses of ammonia and NOx that lead to acid precipitation, and leaching and run-off losses that result in high nitrate levels in groundwater and eutrophication of rivers and lakes. The reasons why farmers overuse nitrogen fertilizer are complex and not fully understood. They involve agro-climate differences between provinces and counties, farming systems and farm income structures. Although there is a wide range of institutional and technological improvements that can greatly reduce this overuse rapid progress in reducing NPS is unlikely. 相似文献
4.
中国化肥使用带来的环境问题 总被引：7，自引：0，他引：7
CAO Zhi-Hong 《土壤圈》1996,6(4):289-303
The current status of chemical fertilizers production and consumption in China as well as their important roles in Chinese modern agriculture are discussed with special concerns to the environmental issues related to chemical fertilizer use.On the one hand.the total amount of chemical fertilizer produced is insufficient to meet the agricultural needs.On the other hand.the production and consumption of chemical fertilizers in China are obviously not balanced.In some areas over application of nitrogen fertilizers and loss of phosphate fertilizer due to soil erosion have resulted in some undesirable environmental problems such as increase of nitrate in water and eutrophication of water bodies.Maximum scientific uses of organic manures in combination with reasonable use of chemical fertilizers are part of good practices not only in increasuing soil productivity and keeping sustainable agriculture development but also in minimizing their detrimental effects on the environment. 相似文献
5.
GIS与氮淋溶模型的结合 总被引：6，自引：0，他引：6
Geographical information systems(GIS) are increasingly being applied to surface and subsurface flow and transport modling issues,In this paper,more attentions are focused on the methodology and strategies of coupling GIS with non-point pollution models.Suggestions are made on how to best itegrate current available or selected nitrogen leaching models ,especially in the aspect of programming development so as to effectively and fiexibly address the specific tasks.The new possibilities for dealing with non-point pollution problems at a regional scale are provided in the resulting integrated approach,including embedding grid-based GIS components in models. 相似文献
6.
中国亚热带丘陵地区典型流域的营养元素释放 总被引：5，自引：0，他引：5
Agriculture is still the biggest contributor of non-point source(NPS) pollution to water bodies and runoff discharges of nutrients and other chemicals are one of the most importtant pathways.This study was conducted during 1998-1999 in a typical watershed with complex agriculture and forestry systems as well as dotted farmer villages,in a transitional region between the mid-and northern subtropical zones of China.Continuous sampling of stream water was performed regularly at a weekly frequency,with additional sampling after all major rainfall events.The discharges of N and P nutrients and suspended materials were measured and the total and area-averaged annual discharges of all components were calculated .The results showed an uneven seasonal distribution of nutrient discharges with summer storms contributing most to the total fluxes.This study demonstrated a high dependence of runoff vlume on rainfall but the overall runoff coefficients were dependent on land use type and watershed size.The area-averaed annual discharges varied greatly among the sub-watershed with differnt sizes and land use structures.This is the first study estimating the area-averaged annual discharges of N and P in the hilly areas of subtropical china,which were 1.5gm^-2 a-1 and 0.1gm^-2a^-1,respectively.providing important reference values for the assessment of regional agricultural non-point source pollution. 相似文献
7.
中国东部精细农业中N肥施用的最新动态和建议 总被引：21，自引：0，他引：21
M. ROELCKE HAN Yong K. H. SCHLEEF ZHU Jian-Guo LIU Gang CAI Zu-Cong J. RICHTER 《土壤圈》2004,14(4):449-460
The Taihu Region in eastern China is one of China‘s most intensive agricultural regions and also one of the economic ally most developed areas. High nitrogen balance surpluses in the summer rice-winter wheat double-cropping systems are leading to large-scMe non-point source pollution of aquifers. In an interdisciplinary approach, four-year (1995-1998) field trials were carried out in two representative areas (Jurong County and Wuxi City) of the Taihu Region. Five farmers‘ field sites were chosen in each of the 2 locations, with each site divided into “standard“ (farmers‘ practice) and “reduced“ (by 30%-40%) N fertilization. For both fertilization intensities, N balance surpluses and monetary returns from grain sales minus fertilizer expenditures were calculated in an economic assessment. Based on the field trials, the mineral N fertilizer application rates reduced by about 10% for rice and 20%-30% for wheat were recommended in 1999. Since 1999, the research focused on the trends in N fertilizer application rates and changes in grain and agricultural commodities prices. Summer rice N fertilizer use, in Wuxi City as of 2001, dropped by roughly 25%, while for winter wheat it decreased by 10%-20%, compared to the 1995-1998 period. This has been achieved not only by grain policy and price changes, but also by an increased environmental awareness from government officials. Nitrogen balance surpluses in Anzhen Town (of Wuxi City) have consequently diminished by 50%-75% in rice and by up to 40% in wheat, with reductions being achieved without concomitant decreases in physical grain yields or returns from sales minus fertilizer costs. 相似文献
8.
Long-term excessive application of mineral fertilizer has led to soil acidification and phosphorus(P) accumulation, increasing the risk of P loss and environmental pollution, and cessation of fertilization is widely considered as a cost-effective management strategy to relieve this situation; however, how such cessation influences P speciation and concentrations in a bulk soil and colloidal fractions and whether decreasing P concentration might maintain soil fertility remain unclear. In this stu... 相似文献
9.
中国水稻土磷储量及其空间分异 总被引：2，自引：1，他引：1
LIN Jin-Shi SHI Xue-Zheng LU Xi-Xi YU Dong-Sheng WANG Hong-Jie ZHAO Yong-Cun SUN Wei-Xia 《土壤圈》2009,19(6):790-798
Due to the growing concern about the agricultural phosphorus (P) losses pollution, an in-depth understanding of P in paddy soils of China would be helpful in providing a national perspective of the environmental impact of P cycling and fertility on China’s farms. In this study, we evaluated the P storage and the P density of paddy soils in China, characterized the spatial variations of P among the subgroups of paddy soils and soil regions in China, and evaluated the P data using GIS-based analysis, which included a newly compiled 1:1 M digital soil map of China, and using 1 490 soil profiles. The available and total P densities of paddy soils were 6.7 and 698.5 g m-3, respectively. Overall in China, the total P storage within 1 m of paddy soils was estimated to be 330.1 Tg. The P density of paddy soils varied substantially with subgroups due to the different soil water regimes such as groundwater table and soil drainage. The P availability in paddy soils, especially in surface layer, was higher in high temperature and precipitation areas. Further research is needed to examine more anthropogenic impact factors, such as increasing use of chemical fertilizer. 相似文献
10.
Application of NaHCO3/ DTPA Extractant-ICP Spectrometry Technique in Soil Test for Availability of Nutrients and Heavy Metals 总被引：1，自引：0，他引：1
CHEN TONG-BIN 《土壤圈》1993,3(4):377-382
Soil test for availability of nutrients and heavy metals is extensively served as a means for the evaluations of soil fertility, and environmental effects and phytotoxicity of pollutants in soils, and for the fertilizer recommendation in agricultural and environmental sciences. Therefore, great attention has been paid to the measurement of elemental availability in soil test. 相似文献
11.
千岛湖区域农业面源污染及其控制对策 总被引：13，自引：1，他引：13
随着对点源污染管理力度的增大，农业面源污染已逐渐成为千岛湖区域的主要污染源之一。以千岛湖区域为研究对象，从畜牧养殖、种植耕作、水产养殖和农村居民生活产生的废物等4个方面系统地分析了千岛湖区域农业面源污染现状，并从控制畜禽养殖污染、水产养殖污染、秸秆和农膜污染、农药与化肥污染、农村居民生活废弃物污染等方面系统地提出了千岛湖区域农业面源污染的应对对策。 相似文献
12.
13.
新疆地区农业面源污染空间分异研究 总被引：4，自引：0，他引：4
新疆维吾尔族自治区是我国重要的农业区之一。为满足农业面源污染控制的实际需要,在GIS支持下,以主要农业面源污染物分析为基础,对新疆地区农业面源污染进行了空间分异研究。结果表明,化肥投入密度超过400 kg/hm2的地区有20个,主要集中在塔里木河、玛纳斯河、伊犁河流域及新疆生产建设兵团;农药面源污染区域的分布与化肥面源污染分布基本相同,从农药投入密度来看,超过3 kg/hm2的地区有18个;畜牧粪尿排泄密度超过30 kg/hm2的地区有13个,畜牧养殖污染从程度上来说北疆地区明显要大于南疆地区;水土流失造成的污染中风蚀占89.32%,水蚀仅占10.68%。对新疆地区面源污染进行聚类分析表明,I类区域属于重污染区域,Ⅱ类区域属于农资类污染区,Ⅲ类区域属于畜牧污染型重污染区域,Ⅳ类地区为轻污染区域。 相似文献
14.
农业非点源污染防治技术的研究现状及进展 总被引：36，自引：8，他引：28
随着点源污染的控制水平的提高,非点源污染的治理成为全球环境问题能否得到有效解决的关键,而农业非点源污染作为其中覆盖面最广、隐蔽性最强、治理难度最大的污染类别,自然受到更为广泛的关注.该文介绍了农业非点源污染及其特征,分析了农业非点源污染扩散的方式,总结了导致农业非点源污染的主要原因,以技术防治为切入点,对现阶段国内外农业非点源污染防治技术的研究进行了简要综述,提出了农业非点源污染防治技术研究中存在的问题,并结合存在的问题在化肥等农业生产投入品的新品研发、农业非点源污染情况的实时监控及预警系统的构建、以及可操作性强的决策支持系统的构建等方面对未来农业非点源污染的技术防治进行了展望. 相似文献
15.
基于农业面源污染控制的三峡库区种植业结构优化 总被引：6，自引：2，他引：4
基于农业经济效益最优和农业面源污染物减排的双重目标,运用线性规划模型,对三峡库区重庆段种植业结构和清洁农业生产进行了优化设计。通过对三峡库区重庆段种植业面源污染控制与种植业发展优化设计,得到三峡库区重庆段农作物净收益最大化的优化路径为:三峡库区重庆段粮食生产用地应保持约119.16×104 hm2,蔬菜用地保持约33.25×104 hm2,烟草、水果、茶用地应维持在17.05×104 hm2;在保证粮食生产稳定的前提下,应逐渐缩减玉米和大豆的种植面积,适当增加烟草、蔬菜、水果和茶的种植面积;在农作物生产过程中应大力推广清洁生产技术,扩大水稻、小麦、油料作物、玉米和大豆等种植的测土配方施肥面积,加强设施蔬菜生产基地建设,提倡蔬菜有机种植。通过这些措施,才能达到农业面源径流氮磷损失量减少30%的预期目标,才能实现农业面源污控制、农业经济转型和可持续发展。 相似文献
16.
农业面源污染具有发生分散、随机，排放不确定性，污染物浓度波动大、类型复杂，污染面广量大的特点，其综合防治一直是世界性难题。当前，我国面源污染防控首要的问题为污染“家底”不清，不同部门或研究学者对农业面源污染负荷估算差别大。基于几十年定位、全程的科学观测数据，本研究认为，虽然国家污染普查数据和很多学者的估算数据，均高估了种植业源排放量占面源污染总量的比例，但种植业源排放总量仍然很高，必须给予充分的重视和防控。结合中国30多年的面源污染防控经验，中国科学院南京土壤研究所学者提出了农业面源污染控制的3R（“减源—拦截—修复”）和4R策略（“源头减量—生态拦截—循环利用—生态修复”），并伴随着防控技术升级和组合优化、技术产品化和装备化，逐渐完善扩展为4R+，为我国农业面源污染防控提供了理论支撑和应用指导，在一些典型地区进行工程化实施后，形成了农业面源污染防控的成功经验和案例。然而，农业面源污染防控的工作仍然面临着许多挑战，深入了解土壤与污染物之间的相互作用机制将尤为关键。此外，为实现资源的高效循环使用，还必须进一步提高氮、磷等关键污染物的净化与回收效率，确保在增加农业产值的同时降低对环境的污染... 相似文献
17.
三峡库区不同农业经营模式的肥料投入评估及其变化特征 总被引：3，自引：0，他引：3
农村生态环境在农村发展中的地位日益突出,研究农业生产转型过程中不同农业经营模式农资投入对解析农村生态环境中非点源污染负荷有重要启示,同样有助于针对性地制定控制面源污染的方案。采用PRA(Participatory Rural Appraisal)方法,抽样采集三峡库区重庆段农业经营主要农作物肥料投入情况,根据整理调研材料、综合评估调研结果划分研究区农业生产经营模式为:一般散户、种植大户、公司企业、养殖大户、种养大户、合作社。核算不同经营模式单位面积肥料投入,确定研究区不同经营模式下用肥量与结构的变化特征。研究结果表明:1)研究区肥料用量总量在1997年到2011年间呈递增趋势,复合肥近年增速明显;2)不同经营模式用肥结构间存在差异,一般散户、养殖大户、种养大户这3种经营模式与种植大户、公司企业、合作社这3种经营模式各自内部又存在相似性,前者常规用肥比例较大,而后者在有机肥、高钾复合肥等肥料的用量及比例方面较高;3)研究区用肥结构以常规肥料为主,其中氮、磷折纯量单位面积投入为一般散户、养殖大户较种植大户、公司企业、养殖大户、种养大户、合作社显著高;4)农户种植结构因经营模式而异,一般散户、养殖大户、种养大户以传统的农作物玉米、水稻、红苕、土豆为主,表现为"小而全"的特性;而种植大户、公司企业、合作社则在技术支撑的前提下表现为以市场为导向、生产特定高附加值农产品。三峡库区重庆段不同农业经营模式中主要农作物单位面积用肥折纯量大小为玉米蔬菜土豆其他作物红苕果木园林水稻。 相似文献
18.
广东省是经济强省也是农业大省。为保障粮食安全,近年来农业发展速度加快,化肥、农药、地膜的大量使用以及畜禽养殖业的迅猛发展等,使得广东省农业面源污染问题日渐凸显。为揭示广东省农业面源污染物排放量和排放来源,阐明农业面源污染的主要特征及发展趋势,该研究基于1991—2021年历史统计数据分析,运用排污系数法估算了广东省各农业面源污染物排放负荷,阐明了农业面源污染的主要来源及其随时间发展的变化趋势。结果显示：1）1991—2021年广东省农业源化学需氧量（chemical oxygen demand,COD）、氨氮（ammonia nitrogen,NH3-N）、总氮（total nitrogen,TN）和总磷（total phosphorus,TP）排放量整体呈现增加趋势,近4年来各污染物排放量出现小幅度降低。与1991年相比,2021年农业源COD、NH3-N、TN和TP排放量分别增长至1.9、1.9、1.7和2.1倍。2）种植业和畜禽养殖业是广东省农业面源污染的主要来源,种植业对农业源NH3-N、TN排放量的贡献率最大（占比分别为48%、52%）,而畜禽养殖业对农业源COD、TP排放量的贡献率最大（占比分别为90%、51%）;此外,水产养殖业对农业源各项水污染物排放总量的贡献率在10%~16%之间,但其排放量及贡献率均呈逐年上升趋势。研究客观分析了1991年来广东省农业面源污染特征及变化趋势,结果可以为农业面源污染防治对策提供科学依据。 相似文献
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四川省化肥面源污染环境风险评估及趋势模拟 总被引：1，自引：1，他引：1
系统评估农业化肥过量施用对生态环境的潜在风险危害,可为制定下一阶段农业面源污染防治工作提供决策参考。本文基于2000—2015年化肥施用量和耕地面积等数据,采用化肥施用环境风险评价模型,探讨了四川省化肥施用及环境风险的时空变化特征;通过设置延续现状和政策干预两种情景,模拟了四川省2016—2018年执行化肥施用零增长行动期间的化肥施用环境风险变化趋势。结果表明:四川省化肥施用总量在2000—2015年间整体呈增加态势,2015年四川省化肥施用强度为376.63 kg?hm~(-2),超过了中国生态市建设的化肥施用强度250 kg?hm~(-2)的生态标准。四川省2015年化肥施用的环境总风险指数为0.69,处于中等风险程度;氮、磷、钾肥施用的环境风险指数分别为0.69、0.72和0.46。钾肥施用的环境风险处于安全状态;氮肥和磷肥的环境风险区域集中在成都平原经济区、川南经济区和川东北经济区,呈现中等风险程度并有成片聚集特征。延续现状情景下,四川各地区化肥施用环境总风险指数处于0.48~0.69,存在不同程度增加。与延续现状情景相比,四川在完成化肥施用零增长行动的任务规划前提下,2016—2018年政策干预情景的化肥施用环境总风险呈现下降趋势。以关键时间点2018年来看,川东北经济区化肥施用环境总风险下降最明显,较2015年执行化肥零增长时下降4.24%。但四川省多数地区仍存在不同程度的化肥施用环境污染风险,当地生态环境具有明显压力。建议省级部门加强对成都平原经济区和川东北经济区的化肥面源污染监测,根据各地区差异特征制定不同施肥方案,协调粮食增产和生态保护间的关系。 相似文献