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在新布伦瑞克西北部的Black Brook小流域内,采用数据库与地理信息系统(GIS)相结合的方法,探讨了描述农地水蚀空间分布特征。同时把USLE各因子值与表示地形分布的相关图结合,在中型机和计算机辅助资源信息系统(CARIS)上建立地理信息系统(GIS)。这些数据的组合,形成了独特的与USLE因子值相结合的各种多边形图,用以处理涉及各种水保生产措施方案的个别数据。GIS和数字数据库的应用吸收了大量信息和人工方法难以处理的数据。根据USLE生成的各因子值预报土壤流失。然后,根据土地生产力受损起始点确定的土壤流失允许值(T)对小流域进行分级。结果表明,以较低投入综合改进土壤管理方法可使小流域内75%农地土壤侵蚀减轻,采取各种作物轮作可解决15%,修建梯田可减少3%,剩下的7%为未实行条播作物的土地。
In the Black Brook watershed in northwest New Brunswick, the spatial distribution characteristics of water erosion in farmland are discussed using a combination of database and geographic information system (GIS). At the same time, the value of each factor in the USLE is combined with the correlation map representing the topography to establish a geographic information system (GIS) on the midsize computer and the computer-aided resource information system (CARIS). The combination of these data forms a unique variety of polygons combined with the USLE factor values to process individual data relating to various measures for the production of conservation measures. The use of GIS and digital databases has absorbed a great deal of information and data that is difficult to manipulate by manual methods. Soil erosion is predicted based on the values of various factors generated by the USLE. The catchment is then graded based on the allowable soil loss (T) determined at the point of origin loss of land productivity. The results showed that soil erosion reduction could be alleviated in 75% of agricultural land in small watershed by comprehensively improving soil management with lower input. Crop rotation can be used to solve 15%, and terraced fields can be reduced by 3%. The remaining 7% is not implemented Land crop planting.