Spatial site selection for a centralized treatment center of livestock excreta: Taking Nantong Town as an example

At present, processing substantial livestock excreta produced by numerous concentrated small–middle-type livestock farms (SMLFs) has been a major problem of livestock farm owners and government departments. To solve this problem, this study established a suitability evaluation system for the spatial layout of a centralized treatment center of livestock excreta (CTCLE). On this basis, combined with the collection points of livestock excreta (CPLEs) determined by spatial clustering algorithm and median center and matched farmlands, the spatial site selection of CTCLE was analyzed using the geographic information system (GIS) spatial analysis method and GIS component development technology. Practical application research was conducted in Nantong Town, and pigs were used as examples. Results showed that most regions of Nantong Town belong to forbidden and unsuitable regions, accounting for 68.63% of the total region of the town. A small part of a highly suitable region (6.428 ha) was determined as potential CTCLE. A total of 839 SMLFs were divided into 61 CPLEs, and the spatial relation between potential CTCLEs and farmlands was established. The spatial sites of 11 CTCLEs in Nantong Town, Minhou County were selected, and the total nitrogen and phosphorus of livestock excreta to be reduced were estimated. The results will provide a scientific basis for the utilization of livestock excreta and the spatial layout planning of livestock and poultry breeding.