CAJ | 학술논문

有效识别流域非点源污染高风险区，对污染控制与管理以及水环境质量改善具有重要意义。该研究以拉萨河流域为研究对象，构建包括降雨、地形和施肥影响因子的输出风险模型，识别流域各级非点源污染输出风险的地域单元。结果表明：1996年和2010年，非点源污染输出风险概率分别为50.0%和46.3%；非点源污染风险处于较高以上程度的区域面积分别为12985.8和11628.0 km2，占全区总面积的38.9%和34.9%；与1996年相比，2010年非点源污染风险程度由低级别向高级别转换的总面积约为6674.3 km2。拉萨河流域非点源污染发生的风险概率为中等，风险程度在局部范围内有所下降，主要表现在高风险区域面积减少、低风险区域面积增加，但是中等和较高风险区域面积有增加趋势。土地利用变化、农业生产和水土流失是非点源污染发生的主要原因，应巩固生态环境综合治理成果，提前应对可能出现的非点源污染问题，制定生态农业发展规划，营造控制非点源污染迁移的植被缓冲带。
유효식별류역비점원오염고풍험구，대오염공제여관리이급수배경질량개선구유중요의의。해연구이랍살하류역위연구대상，구건포괄강우、지형화시비영향인자적수출풍험모형，식별류역각급비점원오염수출풍험적지역단원。결과표명：1996년화2010년，비점원오염수출풍험개솔분별위50.0%화46.3%；비점원오염풍험처우교고이상정도적구역면적분별위12985.8화11628.0 km2，점전구총면적적38.9%화34.9%；여1996년상비，2010년비점원오염풍험정도유저급별향고급별전환적총면적약위6674.3 km2。랍살하류역비점원오염발생적풍험개솔위중등，풍험정도재국부범위내유소하강，주요표현재고풍험구역면적감소、저풍험구역면적증가，단시중등화교고풍험구역면적유증가추세。토지이용변화、농업생산화수토류실시비점원오염발생적주요원인，응공고생태배경종합치리성과，제전응대가능출현적비점원오염문제，제정생태농업발전규화，영조공제비점원오염천이적식피완충대。
Identification of the high risk area of non-point source pollution has important practical significance to control non-point source pollution and improve the water environment quality. Lasahe River basin located in the Tibet Autonomous Region of China is important drinking-water source for Lhasa City, Linzhou County and Dangxiong County. Because the underdevelopment of industry and the less discharge of industrial pollutants in this area, non-point source pollution is the most important contributing factor for water pollution. Lhasa River basin is the region of agricultural production base with the densest population in the Tibet Autonomous Region. This study built the output risk model that includes rainfall, topography, and fertilization influence factor, identification the output risk region unit from basin non-point source pollution at all levels object. The risk probability of non-point source pollution was classed into five levels: lowest, lower, moderate, higher and highest. Data used in this study were mainly from remote sensing image, statistical yearbook, and the parameters in output risk model were collected from the literatures. The results showed that risk probability of non-point source pollution output in 1996 and 2010 was 50%and 46.3%respectively. 17.5%in 1996 and 12.6%in 2010 of the study area showed that risk probability of non-point source pollution was more than 70%. The risk probability of non-point source pollution was spatially heterogeneous, corresponding with the attributes of land use types. The areas with highest risk of non-point source pollution were concentrated in farmland, where agricultural activities strengthened, and concentrated in unused land with great ecological vulnerability and sensitivity to external interference. Areas with lowest and lower risk of non-point source pollution mainly distributed in grassland, which has relative stability and robustness. Our study also found that risk probability of non-point source pollution was closely related with slope, the risk enhanced as the slope increased, and moderate risk, higher risk and highest risk mainly distributed in the area with slope greater than 15 degree. Compared with 1996, the area that non-point source pollution degree of risk transformation from lowest and lower level to higher and highest level in 2010 was about 6674.3km2. Lasahe basin non-point source pollution risk probability was medium risk level, and degree of risk decreased in the local scope. And the area of highest risk reduced, and the area of low risk increased, but the area of medium and higher risk had a tendency to increase. Land use change, agricultural production and water-soil erosion are the material cause of the basin non-point source pollution. Areas characterized by conversion from grassland to farmland and from grassland to unused land showed markedly changes in risk probability of non-point source pollution. These results would offer useful information for limiting non-point pollution and helping promote better water quality in the Lhasa River basin. The risk assessment of non-point source pollution provide an easy, verifiable, viable way to identify areas prone to non-point source pollution, supporting to design and apply adaptive management strategies. Therefore, it needs to strengthen the ecological environment comprehensive treatment results, tackle non-point source pollution in advance, formulate plans for the development of ecological agriculture, and build controlling non-point source pollution migration vegetation buffer.