Based on the integration of C#.net and SuperMap Objects(tool software of component GIS),the management system of regional pollution source is developed.It mainly includes the demand analysis of system,function design,...Based on the integration of C#.net and SuperMap Objects(tool software of component GIS),the management system of regional pollution source is developed.It mainly includes the demand analysis of system,function design,database construction,program design and concrete realization in the management aspect of pollution source.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
Data collection, factor composition, nappe analysis and integrative simulation of natural geographical factors in Erlong Lake watershed have been carried out based on GIS. The risk areas where non-point source polluti...Data collection, factor composition, nappe analysis and integrative simulation of natural geographical factors in Erlong Lake watershed have been carried out based on GIS. The risk areas where non-point source pollution may occur were compartmentalized and assessed, and the total soil erosion and the runoffs of N and P with rainfall in this valley were worked out by experiment and GIS mapping. The study indicated that the main type of soil erosion was moderate (erosion modulus is 1000-2500t/(km2·a)) at present , and the intense erosion areas are located in dry land with variable slope east of the lake and the midded ied ied ied ied ied ied ied iuntainous region (erosion modulus is more than 5000t/(km2·a)). Though the area is small, it should be paid attention to. The trend of non-point source pollution (NSP) of nitrogen and phosphorus loss was corresponded with the soil erosion. Spatial distribution and the reasons of the distribution difference have been presented and it was emphasized that the human activities among the influence factors was the most important. It surely offers a scientific basis to control and prevent non-point source pollution in the watershed.展开更多
Ammonia nitrogen (NH4+-N) is one of the three main forms of total nitrogen (TN). Most studies have estimated the load of TN from nonpoint sources instead of one specific form. The relationship between land use and con...Ammonia nitrogen (NH4+-N) is one of the three main forms of total nitrogen (TN). Most studies have estimated the load of TN from nonpoint sources instead of one specific form. The relationship between land use and concentrations of NH4+-N in runoff was analyzed using the hydraulic analysis functions of a Geographic Information Systems (GIS), and the annual loads of NH4+-N in the Xitiao River catchment were estimated according to model results. The results suggested that the calculated annual loads of NH4+-N...展开更多
堆肥能够在有效地处理有机生活垃圾的同时生产肥料产品,但堆肥过程中产生的恶臭气体是影响环境的重要因素,严重影响了该项技术的推广应用。为确定堆肥厂恶臭来源和强度,进而为进一步治理提供参考。笔者通过先期调查对堆肥厂存在的恶臭...堆肥能够在有效地处理有机生活垃圾的同时生产肥料产品,但堆肥过程中产生的恶臭气体是影响环境的重要因素,严重影响了该项技术的推广应用。为确定堆肥厂恶臭来源和强度,进而为进一步治理提供参考。笔者通过先期调查对堆肥厂存在的恶臭污染释放点进行了初步确定,利用GPS(global position system)定位技术进行网格化布点。在为期30 d的调查过程中,通过电子鼻检测手段分别对堆肥厂厂区和周边环境的恶臭污染状况进行检测。在获得大量现场检测数据的基础上选择GIS(geographic information system)技术中的张力样条法对调查区域进行插值运算,依据生成的数值绘制该区域恶臭污染的等强度曲线。通过作图能够直观地了解恶臭污染分布及浓度梯度下降趋势。对厂区的调查结果作图表明在堆肥厂厂区主要存在着2个主要的恶臭污染释放点源,一个位于发酵车间前段渗滤液抽排外运出口,电子鼻检测数值显示2465,另一个位于与生物滤池附近,电子鼻检测数值显示2913,通过折算臭气浓度分别为840和2191。其中发酵车间附近渗滤液抽排外运出口的取样点邻近与填埋场划定的厂界,其数值远远超过恶臭污染排放标准(GB14554-1993)规定的无组织排放厂界臭气浓度值。2个污染释放源的恶臭强度均达到5级水平。通过对周边环境的更大范围内的恶臭状况检测与比较分析,可以确定堆肥厂的恶臭污染是影响周边环境的首要恶臭因素。展开更多
文摘Based on the integration of C#.net and SuperMap Objects(tool software of component GIS),the management system of regional pollution source is developed.It mainly includes the demand analysis of system,function design,database construction,program design and concrete realization in the management aspect of pollution source.
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.
文摘Data collection, factor composition, nappe analysis and integrative simulation of natural geographical factors in Erlong Lake watershed have been carried out based on GIS. The risk areas where non-point source pollution may occur were compartmentalized and assessed, and the total soil erosion and the runoffs of N and P with rainfall in this valley were worked out by experiment and GIS mapping. The study indicated that the main type of soil erosion was moderate (erosion modulus is 1000-2500t/(km2·a)) at present , and the intense erosion areas are located in dry land with variable slope east of the lake and the midded ied ied ied ied ied ied ied iuntainous region (erosion modulus is more than 5000t/(km2·a)). Though the area is small, it should be paid attention to. The trend of non-point source pollution (NSP) of nitrogen and phosphorus loss was corresponded with the soil erosion. Spatial distribution and the reasons of the distribution difference have been presented and it was emphasized that the human activities among the influence factors was the most important. It surely offers a scientific basis to control and prevent non-point source pollution in the watershed.
基金the National Key BasiResearch Project of China (No. G2002CB410807)the National Natural Science Foundation of China (No40571146)
文摘Ammonia nitrogen (NH4+-N) is one of the three main forms of total nitrogen (TN). Most studies have estimated the load of TN from nonpoint sources instead of one specific form. The relationship between land use and concentrations of NH4+-N in runoff was analyzed using the hydraulic analysis functions of a Geographic Information Systems (GIS), and the annual loads of NH4+-N in the Xitiao River catchment were estimated according to model results. The results suggested that the calculated annual loads of NH4+-N...
文摘堆肥能够在有效地处理有机生活垃圾的同时生产肥料产品,但堆肥过程中产生的恶臭气体是影响环境的重要因素,严重影响了该项技术的推广应用。为确定堆肥厂恶臭来源和强度,进而为进一步治理提供参考。笔者通过先期调查对堆肥厂存在的恶臭污染释放点进行了初步确定,利用GPS(global position system)定位技术进行网格化布点。在为期30 d的调查过程中,通过电子鼻检测手段分别对堆肥厂厂区和周边环境的恶臭污染状况进行检测。在获得大量现场检测数据的基础上选择GIS(geographic information system)技术中的张力样条法对调查区域进行插值运算,依据生成的数值绘制该区域恶臭污染的等强度曲线。通过作图能够直观地了解恶臭污染分布及浓度梯度下降趋势。对厂区的调查结果作图表明在堆肥厂厂区主要存在着2个主要的恶臭污染释放点源,一个位于发酵车间前段渗滤液抽排外运出口,电子鼻检测数值显示2465,另一个位于与生物滤池附近,电子鼻检测数值显示2913,通过折算臭气浓度分别为840和2191。其中发酵车间附近渗滤液抽排外运出口的取样点邻近与填埋场划定的厂界,其数值远远超过恶臭污染排放标准(GB14554-1993)规定的无组织排放厂界臭气浓度值。2个污染释放源的恶臭强度均达到5级水平。通过对周边环境的更大范围内的恶臭状况检测与比较分析,可以确定堆肥厂的恶臭污染是影响周边环境的首要恶臭因素。
