The estimation of non-point source pollution loads into the Danjiangkou Reservoir is highly significant to environmental protection in the watershed. In order to overcome the drawbacks of traditional watershed numeric...The estimation of non-point source pollution loads into the Danjiangkou Reservoir is highly significant to environmental protection in the watershed. In order to overcome the drawbacks of traditional watershed numerical models, a base flow separation method was established coupled with a digital filtering method and a flux method. The digital filtering method has been used to separate the base flows of the Hanjiang,Tianhe, Duhe, Danjiang, Laoguan, and Qihe rivers. Based on daily discharge, base flow, and pollutant concentration data, the flux method was used to calculate the point source pollution load and non-point source pollution load. The results show that:(1) In the year 2013, the total inflow of the six rivers mentioned above accounted for 95.9% of the total inflow to the Danjiangkou Reservoir. The total pollution loads of chemical oxygen demand(CODMn) and total phosphorus(TP) from the six rivers were 58.20 103 t and 1.863 10~3 t, respectively, and the non-point source pollution loads were 39.82 10~3 t and 1.544 10~3 t, respectively, indicating that the non-point source pollution is a major factor(with a contribution rate of 68.4% for CODMnand 82.9% for TP).(2) The Hanjiang River is the most significant contributor of pollution loads to the Danjiangkou Reservoir, and its CODMnand TP contribution rates reached 79.3% and 83.2%, respectively. The Duhe River took the second place.(3) Non-point source pollution mainly occurred in the wet season in 2013, accounting for 80.8% and 90.9% of the total pollution loads of CODMnand TP, respectively. It is concluded that the emphasis of pollution control should be placed on non-point source pollution.展开更多
[Objective] The aim was to study the control countermeasures of agricultural non-point source pollution in lakeside belt of Poyang Lake.[Method] The current situation of water quality of Poyang Lake was analyzed first...[Objective] The aim was to study the control countermeasures of agricultural non-point source pollution in lakeside belt of Poyang Lake.[Method] The current situation of water quality of Poyang Lake was analyzed firstly,then the causes of agricultural non-point source pollution in Duchang section of Poyang Lake were studied,finally corresponding control countermeasures were put forward.[Result] Agricultural non-point source pollution in Duchang section of Poyang Lake was mainly related to the rapid development of pearl industry and livestock industry,aggravated soil erosion and excessive utilization of fertilizer.Based on analysis of current environmental situation and bearing capability of resources in Poyang Lake basin,agricultural non-point source pollution would be controlled through the reduction of external source pollution load,restoration of river wetland and construction of aquatic ecosystem.After the primary implementation of agricultural non-point source pollution control project,the amount of agricultural non-point source pollution in demonstration plot was reduced,and the quality of effluent met the first Class (Class A) of state Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB18918-2002).Meanwhile,biodiversity index in river wetland increased by about 30%,so the pollution load entering Poyang Lake was decreased.[Conclusion] The study could provide technology integration and demonstration for the environmental remediation in lakeside belt of Poyang Lake.展开更多
Based on Kunming statistical yearbook and field survey data of agricultural non-point source pollution in counties or districts in the Dianchi Lake basin,previous and current situation of agricultural production and a...Based on Kunming statistical yearbook and field survey data of agricultural non-point source pollution in counties or districts in the Dianchi Lake basin,previous and current situation of agricultural production and agricultural non-point source pollution control in the Dianchi Lake basin were studied,and countermeasures and suggestions of comprehensive control of agricultural non-point source pollution in the basin were proposed.展开更多
Ascertaining the relationship between "source-sink" landscape and non-point source(NPS) pollution is crucial for reducing NPS pollution, however, it is not easy to realize this target on cell unit scale. To ...Ascertaining the relationship between "source-sink" landscape and non-point source(NPS) pollution is crucial for reducing NPS pollution, however, it is not easy to realize this target on cell unit scale. To reveal the relationships between "sourcesink" landscape and NPS pollution based on cell units of a small catchment in the Three Gorges Reservoir Region(TGRR), the runoff and nutrient yields were simulated first by rainfall events on a cell unit scale based on the Annualized AGricultural Non-Point Source Pollution Model(AnnAGNPS). Landscape structure and pattern were quantified with "sourcesink" landscape indicators based on cell units including landscape area indices and locationweighted landscape indices. The results showed that:the study case of small Wangjiagou catchment highlighted a good prediction capability of runoff and nutrient export by the AnnAGNPS model. Throughout the catchment, the spatial distribution trends of four location-weighted landscape indices were similar to the trends of simulated total nitrogen(TN) and total phosphorus(TP), which highlighted the importance of spatial arrangement of "source" and "sink" landscape types in a catchment when estimating pollutant loads. Results by Pearson correlation analysis indicated that the location-weighted landscape index provided a more comprehensive account of multiple factors, and can better reflect NPS-related nutrient loss than other landscape indices applied in single-factor analysis. This study provides new findings for applying the "source-sink" landscape indices based on cell units in small catchments to explain the effect of "source-sink" landscape on nutrient export based on cell unit, and helps improve the understanding of the correlation between "source-sink" landscape and NPS pollution.展开更多
Taihu Lake is located at the center of Changjiang delta region, the Lake and its effluent rivers are important water sources for 40 million around inhabitants and rapidly increasing industrial factories in Shanghai, J...Taihu Lake is located at the center of Changjiang delta region, the Lake and its effluent rivers are important water sources for 40 million around inhabitants and rapidly increasing industrial factories in Shanghai, Ji-angsu and Zhejiang. The pollutants originate mainly from acidy rain, home sewage of the vast number of inhabitants, livestock manure, agricultural fertilizers & pesticides applied over fields in the drainage basin, and the industrial sewage. Due to the kinds of pollutants, the Lake water is getting highly eutrophic, with frequent blooms of blue-green algae. Compared with point-source pollutants, diffuse pollution is much com-plicated and difficult to control. Thus combating non-point pollution (NPP) is paid much great attention. Based on analysis on source-sink of NPP in Taihu Lake basin, it is concluded that the function of forests on NPP control is multiple and important by both source reduction and sink expansion. The primary objective of planting trees through constructing forested wetlands and establishing riparian forest buffers is to control soil & water erosion, decrease agrochemicals application, and improve farming conditions in the region of Taihu Lake basin. Moreover forests help to intercept acidy rain, protect streambanks, uptake nutrients, hold up pollutants and provide habitat for wildlife.展开更多
[Objective] The aim was to study the control model of rural non-point source pollution.[Method] Taking Ninghe County(a typical agricultural county in Tianjin) as an example,the current development of local economy and...[Objective] The aim was to study the control model of rural non-point source pollution.[Method] Taking Ninghe County(a typical agricultural county in Tianjin) as an example,the current development of local economy and society and characteristics of rural non-point source pollution were studied firstly,then the control model of rural non-point source pollution suitable for Ninghe County was constructed,and its environmental and economic benefits were analyzed finally.[Result] According to the sources of non-point source pollution,the control model of rural non-point source pollution in Ninghe County was divided into three modules from the aspects of planting industry,livestock raising industry and rural living.The main content of non-point source pollution control module of planting industry was composed of rational utilization of chemicals,water-saving irrigation,diversified utilization of straw etc.Non-point source pollution control module of livestock raising industry focused on the site selection of farm or raising zones,choice of raising mode,comprehensive utilization of livestock waste etc.In the non-point source pollution control module of rural living,villages were divided into two types(small town and ecological village) based on various geographical positions.In a word,these three modules were interrelated and targeted for non-point source pollution control in villages under different development situations.[Conclusion] The study could provide references for the rural non-point source pollution control in Hai River basin and other regions of Northern China.展开更多
The main causes of non-point source pollution in Taihu Lake are the improper ways of crop production, animal husbandry, and daily runoff. The paper discusses the relationship between countrywomen and non-point source ...The main causes of non-point source pollution in Taihu Lake are the improper ways of crop production, animal husbandry, and daily runoff. The paper discusses the relationship between countrywomen and non-point source pollution control by 731 questionnaires in Weidu village and 466 questionnaires in Dapu Town. The roles of countrywomen have changed in families and they have close relationship with non-point source pollution. Furthermore, we discuss the possibility and methods of organizing countrywomen in non-point source pollution control.展开更多
Changes in natural geographic features and landscape patterns directly influence the hydrology and non-point source pollution processes in the watershed;however,to slow down non-point source pollution,it is necessary ...Changes in natural geographic features and landscape patterns directly influence the hydrology and non-point source pollution processes in the watershed;however,to slow down non-point source pollution,it is necessary to distinguish their effects.But the non-point source pollution process is interactional as a result of multiple factors,and the collinearity between multiple independent variables limits our ability of reason diagnosis.Thus,taking the Burhatong River Basin,Northeast China as an example,the methods of hydrological simulation,geographic detectors,and redundancy analysis have been combined to determine the impact of natural geographic features and landscape patterns on non-point source pollution in the watershed.The Soil&Water Assessment Tool(SWAT)has been adopted to simulate the spatial and temporal distribution characteristics of total nitrogen and total phosphorus in the watershed.The results show that the proportions of agricultural land and forest area and the location-weighted landscape contrast index(LWLI)are the main indicators influencing the rivers total nitrogen and total phosphorus.The interaction of these indicators with natural geographic features and landscape configuration indicators also significantly influences the changes in total nitrogen(TN)and total phosphorus(TP).Natural geographical features and landscape patterns have different comprehensive effects on non-point source pollution in the dry and wet seasons.TN and TP loads are affected mainly by the change in landscape pattern,especially in the wet season.Although the ecological restoration program has improved forest coverage,the purification effect of increased forest coverage on the water quality in the watershed may be offset by the negative impact of increased forest fragmentation.The high concentration and complexity of farmland patches increase the risk of non-point source pollution spread to a certain extent.展开更多
Agricultural non-point source pollution has become the main part of water pollution prevention and control in China. This paper made a brief introduction to the causes and hazards of agricultural non-point source poll...Agricultural non-point source pollution has become the main part of water pollution prevention and control in China. This paper made a brief introduction to the causes and hazards of agricultural non-point source pollution and the current situation of agricultural non-point source pollution prevention and control in China. In view of the serious agricultural non-point source pollution in water environment of Guangxi and the difference in quality of drinking water between urban and rural areas,it came up with recommendations for strengthening agricultural non-point source pollution prevention and control from scientific distribution,linked operation and maintenance,popular science education,and legal system construction,to guarantee safe and healthy drinking water in rural areas.展开更多
In this study,an inventory analysis approach was used to investigate the intensity of agricultural non-point source pollution(ANSP)and its spatial convergence at national and provincial levels in China from 1999 to 20...In this study,an inventory analysis approach was used to investigate the intensity of agricultural non-point source pollution(ANSP)and its spatial convergence at national and provincial levels in China from 1999 to 2017.On this basis,spatial factors affecting ANSP were explored by constructing a spatial econometric model.The results indicate that:1)The intensity of China's ANSP emission showed an overall upward trend and an obvious spatial difference,with the values being high in the eastern and central regions and relatively low in the western region.2)Significant spatial agglomeration was shown in China's ANSP intensity,and the agglomeration effect was increasing gradually.3)In the convergence analysis,a spatial lag model was found applicable for interpretation of the ANSP intensity,with the convergence rate being accelerated after considering the spatial factors but slower than that of regional economic growth.4)The spatial factors affecting the ANSP intensity are shown to be reduced by improving agricultural infrastructure investment,labor-force quality,and crop production ratio,while the expansion of agricultural economy scale and precipitation and runoff have positive impact on ANSP in the study region.However,agricultural research and development(R&D)investment showed no direct significant effect on the ANSP intensity.Meanwhile,improving the quality of the labor force would significantly reduce the ANSP intensity in the surrounding areas,while the precipitation and runoff would significantly increase the pollution of neighboring regions.This research has laid a theoretical basis for formulation and optimization of ANSP prevention strategies in China and related regions.展开更多
Non-point source nitrogen loss poses a risk to sustainable aquatic ecosystems. However, non-point sources, as well as impaired river segments with high nitrogen concentrations, are difficult to monitor and regulate be...Non-point source nitrogen loss poses a risk to sustainable aquatic ecosystems. However, non-point sources, as well as impaired river segments with high nitrogen concentrations, are difficult to monitor and regulate because of their diffusive nature, budget constraints, and resource deficiencies. For the purpose of catchment management, the Bayesian maximum entropy approach and spatial regression models have been used to explore the spatiotemporal patterns of non-point source nitrogen loss. In this study, a total of 18 sampling sites were selected along the river network in the Hujiashan Catchment. Over the time period of 2008e2012, water samples were collected 116 times at each site and analyzed for non-point source nitrogen loss. The morphometric variables and soil drainage of different land cover types were studied and considered potential factors affecting nitrogen loss. The results revealed that, compared with the approach using the Euclidean distance, the Bayesian maximum entropy approach using the river distance led to an appreciable 10.1% reduction in the estimation error, and more than 53.3% and 44.7% of the river network in the dry and wet seasons, respectively, had a probability of non-point source nitrogen impairment. The proportion of the impaired river segments exhibited an overall decreasing trend in the study catchment from 2008 to 2012, and the reduction in the wet seasons was greater than that in the dry seasons. High nitrogen concentrations were primarily found in the downstream reaches and river segments close to the residential lands. Croplands and residential lands were the dominant factors affecting non-point source nitrogen loss, and explained up to 70.7%of total nitrogen in the dry seasons and 54.7% in the wet seasons. A thorough understanding of the location of impaired river segments and the dominant factors affecting total nitrogen concentration would have considerable importance for catchment management.展开更多
Landuse is one of the most influential factors of non-point source pollution. Based on the three-year landuse data( 2000,2005 and 2008),Arc GIS and Fragstat were used to analyze the landuse type and the change of land...Landuse is one of the most influential factors of non-point source pollution. Based on the three-year landuse data( 2000,2005 and 2008),Arc GIS and Fragstat were used to analyze the landuse type and the change of landscape pattern. The relationships between landuse and non-point source-total nitrogen( NPS-TN) and nonpoint source-total phosphorus( NPS-TP) were discussed with the methods of spatially statistical analysis,landscape pattern analysis and principal component analysis. The study results conveyed that agricultural land and forestland,which accounted for over 92% of the study area,were the major landuse type of Ashi River Basin.Meanwhile,the NPS pollution had close connections with landuse type and landscape pattern. When it comes to landuse type,the export risks of NPS-TN and NPS-TP were agricultural land > urban land > grassland > forestland. As for landscape pattern,NPS-TN and NPS-TP were positively related to SHDI and SHEI, while negatively connected with LPI,AI and COHESION. Therefore,the study could reach the conclusion that the more fragmented and complicated the landscape patterns were,the more serious the NPS pollution was.展开更多
According to China’s second national survey of pollution sources, the contribution of agricultural non-point sources(ANS) to water pollution is still high. Risk prevention and control are the main means to control co...According to China’s second national survey of pollution sources, the contribution of agricultural non-point sources(ANS) to water pollution is still high. Risk prevention and control are the main means to control costs and improve the efficiency of ANS, but most studies directly take pollution load as the risk standard, leading to a considerable misjudgment of the actual pollution risk. To objectively reflect the risk of agricultural non-point source pollution(ANSP) in Chongqing, China, we investigated the influences of initial source input, intermediate transformation, and terminal absorption of pollutants via literature research and the Delphi method and built a PTA(pressure kinetic energy, transformation kinetic energy, and absorption kinetic energy) model that covers 12 factors, with the support of geographical information system(GIS) technology. The terrain factor calculation results and the calculation results of other factors were optimized by Python tools to reduce human error and workload. Via centroid migration analysis and Kernel density analysis, the risk level, spatial aggregation degree, and key prevention and control regions could be accurately determined. There was a positive correlation between the water quality of the rivers in Chongqing and the risk assessment results of different periods, indirectly reflecting the reliability of the assessment results by the proposed model. There was an obvious tendency for the low-risk regions transforming into high-risk regions. The proportion of high-risk regions and extremely high-risk regions increased from 17.82% and 16.63%in 2000 to 18.10% and 16.76% in 2015, respectively. And the risk level in the main urban areas was significantly higher than that in the southeastern and northeastern areas of Chongqing. The centroids of all grades of risky areas presented a successive distribution from west to east, and the centroids of high-risk and extremely high-risk regions shifted eastward. From 2000 to 2015, the centroids of highrisk and extremely high-risk regions moved 4.63 km(1.68°) and 4.48 km(12.08°) east by north, respectively. The kernel density analysis results showed that the high-risk regions were mainly concentrated in the main urban areas and that the distribution of agglomeration areas overall displayed a transition trend from contiguous distribution to decentralized concentration. The risk levels of the regions with a high proportion of cultivated land and artificial surface were significantly increased, and the occupation of cultivated land in the process of urbanization promoted the movement of the centroids of high-risk and extremely high-risk regions. The identification of key areas for risk prevention and control provides data scientific basis for the development of prevention and control strategies.展开更多
Non-point source(NPS) water pollution generated by agricultural production has become a major environmental issue in agroforestry watersheds such as the Three Gorges. Landscape ecology emphasizes the regulation and ef...Non-point source(NPS) water pollution generated by agricultural production has become a major environmental issue in agroforestry watersheds such as the Three Gorges. Landscape ecology emphasizes the regulation and effect of landscape pattern on material flow, energy flow in the ecological processes. This paper reviewed landscape ecological approaches of controlling non-point source pollution in agroforestry watershed of the Three Gorges from the patch level and landscape level. Stage I: landscape ecological investigation. The investigation is to fi gure out landscape pattern characteristics of the watershed, major causes and key sections of the non-point source pollution, "source" patches and ecological process of non-point source pollution, and the feedback relationship between landscape pattern and non-point source pollution. Stage II: landscape ecological planning. In the patch level, the best management procedures(BMPs) are selected to judge the application effect. In the landscape level, new landscape elements are introduced, "source" and "sink" landscape patch types adjusted, landscape level regulation effect assessed. Stage III: landscape ecological management. Small-watershed landscape ecological construction is carried out from patch level and landscape level, BMPs implemented gradually, landscape ecological planning and management integrated, landscape heterogeneity enhanced, intensity of non-point source pollution controlled effectively to achieve sustainable development of small watersheds.展开更多
On the basis of investigating rural population, land types, livestock and poultry breeding scale in drinking water conservation area of the Hongfeng Lake in Guiyang City, as well as the urban domestic pol utant discha...On the basis of investigating rural population, land types, livestock and poultry breeding scale in drinking water conservation area of the Hongfeng Lake in Guiyang City, as well as the urban domestic pol utant discharge coefficient, livestock and poultry excretion coefficient, nitrogen fertilizer and phosphate fertilizer loss rate in the first national pollution source survey, this paper tried to explore current situation of agricultural non-point source pollution, and provide scientific support for the pollution control. The results showed that in the drinking water conservation area of the Hongfeng lake in 2013, contribution rate of pollution sources to the water pollution in the Hongfeng Lake followed the sequence "livestock and poultry breeding > rural life > farmland fertilizer". Among all agricultural non-point source pollutants, livestock and poultry breeding pollutants were major pollution sources, with a contribution rate to CODCr, TP and NH3-N in water above 50%; rural domestic pollutants were also important pollution sources, its contribution rate to CODCr and NH3-N was 43.49% and 46.69%, respectively; contribution rate of farmland fertilizer pollutants to TN and TP was 33.76% and 27.71%, respectively, higher than that of rural domestic pollutants(25.87% and 6.75%). Therefore, the control of non-point source pollution within the drinking water conservation area should be enhanced, so as to control the pollution from the source.展开更多
In order to get a thorough understanding of non-point source pollution,it is essential to examine its temporal and spatial distribution. A physically-based distributed model,Soil and Water Assessment Tool( SWAT),was u...In order to get a thorough understanding of non-point source pollution,it is essential to examine its temporal and spatial distribution. A physically-based distributed model,Soil and Water Assessment Tool( SWAT),was used in this research,to quantitatively estimate the NPS load and analyze the temporal and spatial distributions of NPS pollution in Ashi River Basin. The results indicated that SWAT was suitable to simulate stream-flow and water quality in Ashi River Basin. Total Nitrogen which was contributed by NPS( NPS-TN) accounted for 32. 47%-62. 61%,and Total Phosphorus which was contributed by NPS( NPS-TP)accounted for 22. 30%- 57. 85% of the total load respectively. In inter-annual timescale,both NPS-TN and NPS-TP were influenced by stream-flow and fertilizer. However,when compared with fertilizer,NPS pollution was more directly affected by stream-flow. In annual timescale,NPS-TN and NPS-TP mainly occurred in flood season( from May to September). In the aspect of space,spatial differences of NPS-TN and NPS-TP were extremely significant. The spatial variations of NPS pollution were mainly influenced by land use,precipitation,soil and slope.展开更多
Based on Kunming statistical yearbook and field survey data of agricultural non-point source pollution in counties or districts in the Dianchi Lake basin,advances in the history,current situation and control measures ...Based on Kunming statistical yearbook and field survey data of agricultural non-point source pollution in counties or districts in the Dianchi Lake basin,advances in the history,current situation and control measures of agricultural non-point source pollution in the basin were summarized to provide theoretical and technical support for the thorough improvement of present situation of water pollution in the basin.展开更多
Based on the TM remote sensing interpretation of land use data of a non-point source polluted area in southern China in 2015, supported by ArcGIS and the fractal theory, this paper established the perimeter-area fract...Based on the TM remote sensing interpretation of land use data of a non-point source polluted area in southern China in 2015, supported by ArcGIS and the fractal theory, this paper established the perimeter-area fractal equation of the spatial structure of land use types, quantitatively calculated the fractal dimension and stability index of various land use types in this non-point source polluted area in 2015, and analyzed the spatial structure characteristics of land use types. The results showed that the fractal dimension values of the different land use types in the research area ranged 1.141–1.657, and the whole fractal dimension of the research area was 1.206. To be specific, the fractal dimension values of unused land, grass land and rural residential land were high, and the fractal dimension values of dry land, paddy filed and waters were low, and the fractal dimension values of urban land, industrial traffic construction land and forest land were moderate. The area of the land use types whose stability index values were 0.2–0.4 accounted for 89.5% of total area, suggesting that the stability of the spatial structure of land use types of Beibei District in 2015 was not high generally. The rural residential land and urban land of the research area should be planned and managed more properly from now on.展开更多
Using the survey data on 340 farmers in Chongqing City,this paper performs an empirical analysis of the factors influencing the non-point source pollution of pesticides. The results show that the older householders wi...Using the survey data on 340 farmers in Chongqing City,this paper performs an empirical analysis of the factors influencing the non-point source pollution of pesticides. The results show that the older householders will apply more pesticides,which may be due to the weak physical strength and weak ability to accept the concept of advanced cultivation; the householders with high level of education will choose to use less pesticides; the pesticide application rate is negatively correlated with whether farmers have participated in agricultural technology training,that is,the farmers having participated in agricultural technology training have stronger ability to scientifically apply pesticides,and in-depth understanding of advanced agricultural production technology and positive and negative effects of pesticides,so they often choose to reduce the application rate of pesticide; the cognitive factor on the role of pesticides in better promoting the growth of crops is significant,which requires the government and relevant departments to carry out concrete publicity of effectiveness and negative impact of different pesticides during the popularization of agricultural science knowledge,to prompt farmers to have a systematic and in-depth understanding of the agricultural nonpoint source pollution caused by pesticides.展开更多
The SWAT model was applied to analyze the temporal-spatial distribution patterns of non-point source pollution loads and the difference of pollution loads of different land use types in Xixi Watershed of Jinjiang Basi...The SWAT model was applied to analyze the temporal-spatial distribution patterns of non-point source pollution loads and the difference of pollution loads of different land use types in Xixi Watershed of Jinjiang Basin. The results showed that both yearly nitrogen and phosphorus pollution loads were evenly distributed during 1973 to 1979,the annual TN pollution from non-point source was 1530 t,or 6. 3 kg / ha,and the annual TP pollution from non-point source was 270 t,or 1. 1 kg / ha during 1973 to 1979 in the watershed. Considerable differences were identified on both monthly nitrogen and phosphorus pollution loads. The TN and TP pollution loads during the flood season( from April to September) accounted for 76. 2% and 75. 8% of the annual load respectively. There were great differences in both TN and TP pollution loads of different land use types in the study area,and the pollution load of both farmland and orchard was higher than that of the other land use types. TN and TP pollution loads of farmland accounted for 66% and 83% of total watershed. There was a great spatial difference in the nonpoint source pollution load of the study area. The critical source areas of non-point source pollution are mainly located at Guanqiao Town,Longmen Town,Changkeng Town,Shangqing Town and Dapu Town,where the efforts of controlling pollution should be made.展开更多
基金supported by the National Key Research and Development Program of China(Grants No.2016YFC0402204 and 2016YFC0402207)
文摘The estimation of non-point source pollution loads into the Danjiangkou Reservoir is highly significant to environmental protection in the watershed. In order to overcome the drawbacks of traditional watershed numerical models, a base flow separation method was established coupled with a digital filtering method and a flux method. The digital filtering method has been used to separate the base flows of the Hanjiang,Tianhe, Duhe, Danjiang, Laoguan, and Qihe rivers. Based on daily discharge, base flow, and pollutant concentration data, the flux method was used to calculate the point source pollution load and non-point source pollution load. The results show that:(1) In the year 2013, the total inflow of the six rivers mentioned above accounted for 95.9% of the total inflow to the Danjiangkou Reservoir. The total pollution loads of chemical oxygen demand(CODMn) and total phosphorus(TP) from the six rivers were 58.20 103 t and 1.863 10~3 t, respectively, and the non-point source pollution loads were 39.82 10~3 t and 1.544 10~3 t, respectively, indicating that the non-point source pollution is a major factor(with a contribution rate of 68.4% for CODMnand 82.9% for TP).(2) The Hanjiang River is the most significant contributor of pollution loads to the Danjiangkou Reservoir, and its CODMnand TP contribution rates reached 79.3% and 83.2%, respectively. The Duhe River took the second place.(3) Non-point source pollution mainly occurred in the wet season in 2013, accounting for 80.8% and 90.9% of the total pollution loads of CODMnand TP, respectively. It is concluded that the emphasis of pollution control should be placed on non-point source pollution.
基金Supported by Horizontal Subject Project of Jiujiang University(2011019)
文摘[Objective] The aim was to study the control countermeasures of agricultural non-point source pollution in lakeside belt of Poyang Lake.[Method] The current situation of water quality of Poyang Lake was analyzed firstly,then the causes of agricultural non-point source pollution in Duchang section of Poyang Lake were studied,finally corresponding control countermeasures were put forward.[Result] Agricultural non-point source pollution in Duchang section of Poyang Lake was mainly related to the rapid development of pearl industry and livestock industry,aggravated soil erosion and excessive utilization of fertilizer.Based on analysis of current environmental situation and bearing capability of resources in Poyang Lake basin,agricultural non-point source pollution would be controlled through the reduction of external source pollution load,restoration of river wetland and construction of aquatic ecosystem.After the primary implementation of agricultural non-point source pollution control project,the amount of agricultural non-point source pollution in demonstration plot was reduced,and the quality of effluent met the first Class (Class A) of state Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB18918-2002).Meanwhile,biodiversity index in river wetland increased by about 30%,so the pollution load entering Poyang Lake was decreased.[Conclusion] The study could provide technology integration and demonstration for the environmental remediation in lakeside belt of Poyang Lake.
基金Supported by Research on the Comprehensive Control Measures of Agricultural Non-point Source Pollution in the Dianchi Lake Basin Funded by Kunming Agricultural Bureau(2016JC01)Project of Yunnan Engineering Research Center for Urban Characteristic Agriculture(TSNY0201)+7 种基金Scientific Research Foundation of Yunnan Department of Education(2014Y390)Application Base Research Project for Young Scholars of Yunnan Province(2013FD040)Talent Introduction Project of Kunming University(YJL14005)Talent Introduction Foundation of Kunming University(YJL12010)Key Foundation of Kunming University(XJL12020)Scientific Research Project for Undergraduates of Kunming University(XJD16081)Research on the Ecology and Rational Distribution of Main Cultivars in Producing Areas of Raw Materials of China Tobacco in Yunnan ProvinceProject of Construction of the Dominant Key Subject(Ecology)in Universities and Colleges in Yunnan Province(05000511311)
文摘Based on Kunming statistical yearbook and field survey data of agricultural non-point source pollution in counties or districts in the Dianchi Lake basin,previous and current situation of agricultural production and agricultural non-point source pollution control in the Dianchi Lake basin were studied,and countermeasures and suggestions of comprehensive control of agricultural non-point source pollution in the basin were proposed.
基金supported by the National Natural Science Foundation of China (Nos. 41671291)
文摘Ascertaining the relationship between "source-sink" landscape and non-point source(NPS) pollution is crucial for reducing NPS pollution, however, it is not easy to realize this target on cell unit scale. To reveal the relationships between "sourcesink" landscape and NPS pollution based on cell units of a small catchment in the Three Gorges Reservoir Region(TGRR), the runoff and nutrient yields were simulated first by rainfall events on a cell unit scale based on the Annualized AGricultural Non-Point Source Pollution Model(AnnAGNPS). Landscape structure and pattern were quantified with "sourcesink" landscape indicators based on cell units including landscape area indices and locationweighted landscape indices. The results showed that:the study case of small Wangjiagou catchment highlighted a good prediction capability of runoff and nutrient export by the AnnAGNPS model. Throughout the catchment, the spatial distribution trends of four location-weighted landscape indices were similar to the trends of simulated total nitrogen(TN) and total phosphorus(TP), which highlighted the importance of spatial arrangement of "source" and "sink" landscape types in a catchment when estimating pollutant loads. Results by Pearson correlation analysis indicated that the location-weighted landscape index provided a more comprehensive account of multiple factors, and can better reflect NPS-related nutrient loss than other landscape indices applied in single-factor analysis. This study provides new findings for applying the "source-sink" landscape indices based on cell units in small catchments to explain the effect of "source-sink" landscape on nutrient export based on cell unit, and helps improve the understanding of the correlation between "source-sink" landscape and NPS pollution.
文摘Taihu Lake is located at the center of Changjiang delta region, the Lake and its effluent rivers are important water sources for 40 million around inhabitants and rapidly increasing industrial factories in Shanghai, Ji-angsu and Zhejiang. The pollutants originate mainly from acidy rain, home sewage of the vast number of inhabitants, livestock manure, agricultural fertilizers & pesticides applied over fields in the drainage basin, and the industrial sewage. Due to the kinds of pollutants, the Lake water is getting highly eutrophic, with frequent blooms of blue-green algae. Compared with point-source pollutants, diffuse pollution is much com-plicated and difficult to control. Thus combating non-point pollution (NPP) is paid much great attention. Based on analysis on source-sink of NPP in Taihu Lake basin, it is concluded that the function of forests on NPP control is multiple and important by both source reduction and sink expansion. The primary objective of planting trees through constructing forested wetlands and establishing riparian forest buffers is to control soil & water erosion, decrease agrochemicals application, and improve farming conditions in the region of Taihu Lake basin. Moreover forests help to intercept acidy rain, protect streambanks, uptake nutrients, hold up pollutants and provide habitat for wildlife.
基金Supported by Hai River Basin Integrated Water Resources Management Project of Global Environment Facility(SEPA-ZWN-3,C/II/S/09/090)
文摘[Objective] The aim was to study the control model of rural non-point source pollution.[Method] Taking Ninghe County(a typical agricultural county in Tianjin) as an example,the current development of local economy and society and characteristics of rural non-point source pollution were studied firstly,then the control model of rural non-point source pollution suitable for Ninghe County was constructed,and its environmental and economic benefits were analyzed finally.[Result] According to the sources of non-point source pollution,the control model of rural non-point source pollution in Ninghe County was divided into three modules from the aspects of planting industry,livestock raising industry and rural living.The main content of non-point source pollution control module of planting industry was composed of rational utilization of chemicals,water-saving irrigation,diversified utilization of straw etc.Non-point source pollution control module of livestock raising industry focused on the site selection of farm or raising zones,choice of raising mode,comprehensive utilization of livestock waste etc.In the non-point source pollution control module of rural living,villages were divided into two types(small town and ecological village) based on various geographical positions.In a word,these three modules were interrelated and targeted for non-point source pollution control in villages under different development situations.[Conclusion] The study could provide references for the rural non-point source pollution control in Hai River basin and other regions of Northern China.
文摘The main causes of non-point source pollution in Taihu Lake are the improper ways of crop production, animal husbandry, and daily runoff. The paper discusses the relationship between countrywomen and non-point source pollution control by 731 questionnaires in Weidu village and 466 questionnaires in Dapu Town. The roles of countrywomen have changed in families and they have close relationship with non-point source pollution. Furthermore, we discuss the possibility and methods of organizing countrywomen in non-point source pollution control.
基金Under the auspices of the National Key R&D Program(No.2019YFC0409104)the National Natural Science Foundation of China(No.41830643)the National Science and Technology Basic Resources Survey Project(No.2019FY101703)。
文摘Changes in natural geographic features and landscape patterns directly influence the hydrology and non-point source pollution processes in the watershed;however,to slow down non-point source pollution,it is necessary to distinguish their effects.But the non-point source pollution process is interactional as a result of multiple factors,and the collinearity between multiple independent variables limits our ability of reason diagnosis.Thus,taking the Burhatong River Basin,Northeast China as an example,the methods of hydrological simulation,geographic detectors,and redundancy analysis have been combined to determine the impact of natural geographic features and landscape patterns on non-point source pollution in the watershed.The Soil&Water Assessment Tool(SWAT)has been adopted to simulate the spatial and temporal distribution characteristics of total nitrogen and total phosphorus in the watershed.The results show that the proportions of agricultural land and forest area and the location-weighted landscape contrast index(LWLI)are the main indicators influencing the rivers total nitrogen and total phosphorus.The interaction of these indicators with natural geographic features and landscape configuration indicators also significantly influences the changes in total nitrogen(TN)and total phosphorus(TP).Natural geographical features and landscape patterns have different comprehensive effects on non-point source pollution in the dry and wet seasons.TN and TP loads are affected mainly by the change in landscape pattern,especially in the wet season.Although the ecological restoration program has improved forest coverage,the purification effect of increased forest coverage on the water quality in the watershed may be offset by the negative impact of increased forest fragmentation.The high concentration and complexity of farmland patches increase the risk of non-point source pollution spread to a certain extent.
基金Supported by State Key Research and Development Program of Ministry of Science and Technology"Soil Passivation-Physiological Barrier-Enrichment and Removal Technology in Paddy Field with Mild Cadmium Contamination"(2016YED0800705-01)Key Research and Development Program of Guangxi"Research and Demonstration of Remediation Technology in Cadmium and Lead Polluted Paddy Field"(Gui Ke AB16380084)+2 种基金Key Agricultural Science and Technology Project of Guangxi"Integration,Research and Development of Heavy Metal Pollution Prevention Technology for Paddy Field"(201528)Scientific Research and Technological Development Program Project of Nanning City"Research and Demonstration of Integrated Ecological Restoration Technology for Heavy Metal Cadmium Polluted Paddy Field in Nanning"(20162105)Scientific and Technological Service Ability and Party Informationization Construction of Ecological Comprehensive Demonstration Village in Jianning No.1 Team of Xixiangtang District of Nanning(20152054-13)
文摘Agricultural non-point source pollution has become the main part of water pollution prevention and control in China. This paper made a brief introduction to the causes and hazards of agricultural non-point source pollution and the current situation of agricultural non-point source pollution prevention and control in China. In view of the serious agricultural non-point source pollution in water environment of Guangxi and the difference in quality of drinking water between urban and rural areas,it came up with recommendations for strengthening agricultural non-point source pollution prevention and control from scientific distribution,linked operation and maintenance,popular science education,and legal system construction,to guarantee safe and healthy drinking water in rural areas.
基金Under the auspices of Key Program of the National Social Science Fund of China(No.16ASH007)。
文摘In this study,an inventory analysis approach was used to investigate the intensity of agricultural non-point source pollution(ANSP)and its spatial convergence at national and provincial levels in China from 1999 to 2017.On this basis,spatial factors affecting ANSP were explored by constructing a spatial econometric model.The results indicate that:1)The intensity of China's ANSP emission showed an overall upward trend and an obvious spatial difference,with the values being high in the eastern and central regions and relatively low in the western region.2)Significant spatial agglomeration was shown in China's ANSP intensity,and the agglomeration effect was increasing gradually.3)In the convergence analysis,a spatial lag model was found applicable for interpretation of the ANSP intensity,with the convergence rate being accelerated after considering the spatial factors but slower than that of regional economic growth.4)The spatial factors affecting the ANSP intensity are shown to be reduced by improving agricultural infrastructure investment,labor-force quality,and crop production ratio,while the expansion of agricultural economy scale and precipitation and runoff have positive impact on ANSP in the study region.However,agricultural research and development(R&D)investment showed no direct significant effect on the ANSP intensity.Meanwhile,improving the quality of the labor force would significantly reduce the ANSP intensity in the surrounding areas,while the precipitation and runoff would significantly increase the pollution of neighboring regions.This research has laid a theoretical basis for formulation and optimization of ANSP prevention strategies in China and related regions.
基金supported by the Special Fund for Agro-Scientific Research in the Public Interest of China(Grant No.201503106)
文摘Non-point source nitrogen loss poses a risk to sustainable aquatic ecosystems. However, non-point sources, as well as impaired river segments with high nitrogen concentrations, are difficult to monitor and regulate because of their diffusive nature, budget constraints, and resource deficiencies. For the purpose of catchment management, the Bayesian maximum entropy approach and spatial regression models have been used to explore the spatiotemporal patterns of non-point source nitrogen loss. In this study, a total of 18 sampling sites were selected along the river network in the Hujiashan Catchment. Over the time period of 2008e2012, water samples were collected 116 times at each site and analyzed for non-point source nitrogen loss. The morphometric variables and soil drainage of different land cover types were studied and considered potential factors affecting nitrogen loss. The results revealed that, compared with the approach using the Euclidean distance, the Bayesian maximum entropy approach using the river distance led to an appreciable 10.1% reduction in the estimation error, and more than 53.3% and 44.7% of the river network in the dry and wet seasons, respectively, had a probability of non-point source nitrogen impairment. The proportion of the impaired river segments exhibited an overall decreasing trend in the study catchment from 2008 to 2012, and the reduction in the wet seasons was greater than that in the dry seasons. High nitrogen concentrations were primarily found in the downstream reaches and river segments close to the residential lands. Croplands and residential lands were the dominant factors affecting non-point source nitrogen loss, and explained up to 70.7%of total nitrogen in the dry seasons and 54.7% in the wet seasons. A thorough understanding of the location of impaired river segments and the dominant factors affecting total nitrogen concentration would have considerable importance for catchment management.
基金National Natural Science Foundation of China(No.51179041)the Major Science and Technology Program for Water Pollution Control and Treatment,China(No.2013ZX07201007)+2 种基金Natural Science Foundation of Heilongjiang Province,China(No.E201206)Special Fund for Science and Technology Innovation of Harbin,China(No.2012RFLXS026)the State Key Lab of Urban Water Resource and Environment(Harbin Institute of Technology),China(No.2014TS05)
文摘Landuse is one of the most influential factors of non-point source pollution. Based on the three-year landuse data( 2000,2005 and 2008),Arc GIS and Fragstat were used to analyze the landuse type and the change of landscape pattern. The relationships between landuse and non-point source-total nitrogen( NPS-TN) and nonpoint source-total phosphorus( NPS-TP) were discussed with the methods of spatially statistical analysis,landscape pattern analysis and principal component analysis. The study results conveyed that agricultural land and forestland,which accounted for over 92% of the study area,were the major landuse type of Ashi River Basin.Meanwhile,the NPS pollution had close connections with landuse type and landscape pattern. When it comes to landuse type,the export risks of NPS-TN and NPS-TP were agricultural land > urban land > grassland > forestland. As for landscape pattern,NPS-TN and NPS-TP were positively related to SHDI and SHEI, while negatively connected with LPI,AI and COHESION. Therefore,the study could reach the conclusion that the more fragmented and complicated the landscape patterns were,the more serious the NPS pollution was.
基金Under the auspices of the Chongqing Science and Technology Commission(No.cstc2018jxjl20012,cstc2018jszx-zdyfxm X0021,cstc2019jscx-gksb X0103)。
文摘According to China’s second national survey of pollution sources, the contribution of agricultural non-point sources(ANS) to water pollution is still high. Risk prevention and control are the main means to control costs and improve the efficiency of ANS, but most studies directly take pollution load as the risk standard, leading to a considerable misjudgment of the actual pollution risk. To objectively reflect the risk of agricultural non-point source pollution(ANSP) in Chongqing, China, we investigated the influences of initial source input, intermediate transformation, and terminal absorption of pollutants via literature research and the Delphi method and built a PTA(pressure kinetic energy, transformation kinetic energy, and absorption kinetic energy) model that covers 12 factors, with the support of geographical information system(GIS) technology. The terrain factor calculation results and the calculation results of other factors were optimized by Python tools to reduce human error and workload. Via centroid migration analysis and Kernel density analysis, the risk level, spatial aggregation degree, and key prevention and control regions could be accurately determined. There was a positive correlation between the water quality of the rivers in Chongqing and the risk assessment results of different periods, indirectly reflecting the reliability of the assessment results by the proposed model. There was an obvious tendency for the low-risk regions transforming into high-risk regions. The proportion of high-risk regions and extremely high-risk regions increased from 17.82% and 16.63%in 2000 to 18.10% and 16.76% in 2015, respectively. And the risk level in the main urban areas was significantly higher than that in the southeastern and northeastern areas of Chongqing. The centroids of all grades of risky areas presented a successive distribution from west to east, and the centroids of high-risk and extremely high-risk regions shifted eastward. From 2000 to 2015, the centroids of highrisk and extremely high-risk regions moved 4.63 km(1.68°) and 4.48 km(12.08°) east by north, respectively. The kernel density analysis results showed that the high-risk regions were mainly concentrated in the main urban areas and that the distribution of agglomeration areas overall displayed a transition trend from contiguous distribution to decentralized concentration. The risk levels of the regions with a high proportion of cultivated land and artificial surface were significantly increased, and the occupation of cultivated land in the process of urbanization promoted the movement of the centroids of high-risk and extremely high-risk regions. The identification of key areas for risk prevention and control provides data scientific basis for the development of prevention and control strategies.
基金Sponsored by Scientifi c Research Program of Public Welfare Industry(Forestry)(201104008)"Twelfth Five-year Plan"of Forestry Science&Technology Support Program(2011BAD38B04)
文摘Non-point source(NPS) water pollution generated by agricultural production has become a major environmental issue in agroforestry watersheds such as the Three Gorges. Landscape ecology emphasizes the regulation and effect of landscape pattern on material flow, energy flow in the ecological processes. This paper reviewed landscape ecological approaches of controlling non-point source pollution in agroforestry watershed of the Three Gorges from the patch level and landscape level. Stage I: landscape ecological investigation. The investigation is to fi gure out landscape pattern characteristics of the watershed, major causes and key sections of the non-point source pollution, "source" patches and ecological process of non-point source pollution, and the feedback relationship between landscape pattern and non-point source pollution. Stage II: landscape ecological planning. In the patch level, the best management procedures(BMPs) are selected to judge the application effect. In the landscape level, new landscape elements are introduced, "source" and "sink" landscape patch types adjusted, landscape level regulation effect assessed. Stage III: landscape ecological management. Small-watershed landscape ecological construction is carried out from patch level and landscape level, BMPs implemented gradually, landscape ecological planning and management integrated, landscape heterogeneity enhanced, intensity of non-point source pollution controlled effectively to achieve sustainable development of small watersheds.
基金Sponsored by Significant Scientific and Technological Program of Guizhou Province([2015]2001)
文摘On the basis of investigating rural population, land types, livestock and poultry breeding scale in drinking water conservation area of the Hongfeng Lake in Guiyang City, as well as the urban domestic pol utant discharge coefficient, livestock and poultry excretion coefficient, nitrogen fertilizer and phosphate fertilizer loss rate in the first national pollution source survey, this paper tried to explore current situation of agricultural non-point source pollution, and provide scientific support for the pollution control. The results showed that in the drinking water conservation area of the Hongfeng lake in 2013, contribution rate of pollution sources to the water pollution in the Hongfeng Lake followed the sequence "livestock and poultry breeding > rural life > farmland fertilizer". Among all agricultural non-point source pollutants, livestock and poultry breeding pollutants were major pollution sources, with a contribution rate to CODCr, TP and NH3-N in water above 50%; rural domestic pollutants were also important pollution sources, its contribution rate to CODCr and NH3-N was 43.49% and 46.69%, respectively; contribution rate of farmland fertilizer pollutants to TN and TP was 33.76% and 27.71%, respectively, higher than that of rural domestic pollutants(25.87% and 6.75%). Therefore, the control of non-point source pollution within the drinking water conservation area should be enhanced, so as to control the pollution from the source.
基金Sponsored by the National Natural Science Foundation of China(Grant No.51179041)the Major Science and Technology Program for Water Pollution Control and Treatment(Grant No.2013ZX07201007)+2 种基金Natural Science Foundation of Heilongjiang Province,China(Grant No.E201206)Special Fund for Science and Technology Innovation of Harbin(Grant No.2012RFLXS026)the State Key Lab of Urban Water Resource and Environment(Harbin Institute of Technology)(Grant No.2014TS05)
文摘In order to get a thorough understanding of non-point source pollution,it is essential to examine its temporal and spatial distribution. A physically-based distributed model,Soil and Water Assessment Tool( SWAT),was used in this research,to quantitatively estimate the NPS load and analyze the temporal and spatial distributions of NPS pollution in Ashi River Basin. The results indicated that SWAT was suitable to simulate stream-flow and water quality in Ashi River Basin. Total Nitrogen which was contributed by NPS( NPS-TN) accounted for 32. 47%-62. 61%,and Total Phosphorus which was contributed by NPS( NPS-TP)accounted for 22. 30%- 57. 85% of the total load respectively. In inter-annual timescale,both NPS-TN and NPS-TP were influenced by stream-flow and fertilizer. However,when compared with fertilizer,NPS pollution was more directly affected by stream-flow. In annual timescale,NPS-TN and NPS-TP mainly occurred in flood season( from May to September). In the aspect of space,spatial differences of NPS-TN and NPS-TP were extremely significant. The spatial variations of NPS pollution were mainly influenced by land use,precipitation,soil and slope.
基金Supported by Research on the Comprehensive Control Measures of Agricultural Non-point Source Pollution in the Dianchi Lake Basin Funded by Kunming Agricultural Bureau(2016JC01)Project of Yunnan Engineering Research Center for Urban Characteristic Agriculture(TSNY0201)+4 种基金Scientific Research Foundation of Yunnan Department of Education(2014Y390)Application Base Research Project for Young Scholars of Yunnan Province(2013FD040)Talent Introduction Project of Kunming University(YJL14005),Talent Introduction Foundation of Kunming University(YJL12010),Key Foundation of Kunming University(XJL12020),Scientific Research Project for Undergraduates of Kunming University(XJD16081)Research on the Ecology and Rational Distribution of Main Cultivars in Producing Areas of Raw Materials of China Tobacco in Yunnan ProvinceProject of Construction of the Dominant Key Subject(Ecology)in Universities and Colleges in Yunnan Province(05000511311)
文摘Based on Kunming statistical yearbook and field survey data of agricultural non-point source pollution in counties or districts in the Dianchi Lake basin,advances in the history,current situation and control measures of agricultural non-point source pollution in the basin were summarized to provide theoretical and technical support for the thorough improvement of present situation of water pollution in the basin.
基金Sponsored by Humanities and Social Sciences Research Project of the Ministry of Education(19YJCZH134)Binzhou University Research Fund(BZXYG1716)Experimental Technology Project Funded by Binzhou University(BZXYSYXM201816)
文摘Based on the TM remote sensing interpretation of land use data of a non-point source polluted area in southern China in 2015, supported by ArcGIS and the fractal theory, this paper established the perimeter-area fractal equation of the spatial structure of land use types, quantitatively calculated the fractal dimension and stability index of various land use types in this non-point source polluted area in 2015, and analyzed the spatial structure characteristics of land use types. The results showed that the fractal dimension values of the different land use types in the research area ranged 1.141–1.657, and the whole fractal dimension of the research area was 1.206. To be specific, the fractal dimension values of unused land, grass land and rural residential land were high, and the fractal dimension values of dry land, paddy filed and waters were low, and the fractal dimension values of urban land, industrial traffic construction land and forest land were moderate. The area of the land use types whose stability index values were 0.2–0.4 accounted for 89.5% of total area, suggesting that the stability of the spatial structure of land use types of Beibei District in 2015 was not high generally. The rural residential land and urban land of the research area should be planned and managed more properly from now on.
基金Supported by Chongqing Humanities and Social Science Key Research Project(11SKB31)Chongqing Philosophy and Social Science Planning Project(2014YBGL130)
文摘Using the survey data on 340 farmers in Chongqing City,this paper performs an empirical analysis of the factors influencing the non-point source pollution of pesticides. The results show that the older householders will apply more pesticides,which may be due to the weak physical strength and weak ability to accept the concept of advanced cultivation; the householders with high level of education will choose to use less pesticides; the pesticide application rate is negatively correlated with whether farmers have participated in agricultural technology training,that is,the farmers having participated in agricultural technology training have stronger ability to scientifically apply pesticides,and in-depth understanding of advanced agricultural production technology and positive and negative effects of pesticides,so they often choose to reduce the application rate of pesticide; the cognitive factor on the role of pesticides in better promoting the growth of crops is significant,which requires the government and relevant departments to carry out concrete publicity of effectiveness and negative impact of different pesticides during the popularization of agricultural science knowledge,to prompt farmers to have a systematic and in-depth understanding of the agricultural nonpoint source pollution caused by pesticides.
基金Supported by Key Technology Project of State Administration of Work Safety Supervision for Prevention and Control of Major Safety Accidents in 2015(Shandong-0052-2015AQ)Shandong Natural Science Foundation(ZR20-14EEP009)+1 种基金Binzhou Science and Technology Development Program(2013ZC1001)Research Fund of Binzhou University(BZXYG1414)
文摘The SWAT model was applied to analyze the temporal-spatial distribution patterns of non-point source pollution loads and the difference of pollution loads of different land use types in Xixi Watershed of Jinjiang Basin. The results showed that both yearly nitrogen and phosphorus pollution loads were evenly distributed during 1973 to 1979,the annual TN pollution from non-point source was 1530 t,or 6. 3 kg / ha,and the annual TP pollution from non-point source was 270 t,or 1. 1 kg / ha during 1973 to 1979 in the watershed. Considerable differences were identified on both monthly nitrogen and phosphorus pollution loads. The TN and TP pollution loads during the flood season( from April to September) accounted for 76. 2% and 75. 8% of the annual load respectively. There were great differences in both TN and TP pollution loads of different land use types in the study area,and the pollution load of both farmland and orchard was higher than that of the other land use types. TN and TP pollution loads of farmland accounted for 66% and 83% of total watershed. There was a great spatial difference in the nonpoint source pollution load of the study area. The critical source areas of non-point source pollution are mainly located at Guanqiao Town,Longmen Town,Changkeng Town,Shangqing Town and Dapu Town,where the efforts of controlling pollution should be made.
