山东省畜禽粪污土地承载力时空分异特征分析

探明山东省畜禽粪污资源的空间分布以及近十年畜禽粪污土地承载力变化情况,为合理利用畜禽粪污资源、优化畜禽养殖结构、推动种养结合的绿色农业发展提供参考。通过文献调研与相关数据资料收集,量化分析山东省作物粪污养分需求量、畜禽粪污养分供应量,将不同畜种产生的畜禽粪便量统一换算为猪粪当量,计算各市畜禽粪污土地承载力指数(I),分析山东省畜禽粪污土地承载力的时空变化特征。山东省畜禽养殖环境承载潜力存在明显的时空变异性。从空间上来看,各市畜禽粪便污染风险存在明显差异,其中青岛、淄博、聊城、菏泽以N、P为基准的I值均小于1,土地消纳畜禽粪污不超载。济南、枣庄、烟台、泰安、威海、日照、莱芜、临沂、德州以N、P为基准的I值均大于1,畜禽粪污量超过了农田的承受能力,农田畜禽污染风险较大,尤其是莱芜市以N、P为基准的土地承载力指数I分别为2.14和2.36,农田畜禽污染风险较大,养分的大量盈余可能会造成农田N、P污染。从时间上来看,近十年山东省养殖规模总体呈上升趋势,从7042万头增加到8401万头,尤其在2009年至2012年间迅速增加,增幅达13.3%。植物对粪污N、P养分的需求量呈逐年上升趋势,分别增长了10.6%、13.1%。畜禽粪污N、P养分供应量呈现上升趋势,增幅分别为8.9%、2.9%。2016年山东省畜禽养殖环境承载潜力以N、P为基准分别可达8576万、9809万头,均高于实际养殖规模(8401万头)。山东省以N、P为基准的畜禽粪污土地承载力指数I均呈波动下降趋势。山东省畜禽养殖主要集中在鲁西南、鲁中南、以及德州、潍坊等区域,其中济南、枣庄、烟台、泰安、威海、日照、莱芜、临沂、德州畜禽粪污量超过了农田的承受能力,有潜在的N、P污染风险。从以N、P为基准的畜禽粪污土地承载力指数I来看,山东省农田对畜禽粪便仍具有一定的消纳空间。

The spatial and temporal distribution features of the land bearing capacity for livestock manure in Shandong Province, China

This research aims to investigate the spatial distribution of livestock and poultry manure resources and the changes in land bearing capacity for livestock and poultry manure over the past decade in Shandong Province. The objectives are to provide scientific information for rational utilization of livestock and poultry feces resources, optimize the structure of livestock breeding, and promote the development of green agriculture combined with planting and breeding. Based on a literature review and official statistical data collection, we quantified crop nutrient demands and nutrient supply from livestock manure. By converting the animal manure produced from different livestock species into pig equivalent to obtain an index of land bearing capacity for livestock and poultry manure, we analyzed the temporal and spatial characteristics of the land bearing capacity for livestock and poultry manure. The results showed that there were significant spatial and temporal variations in the distribution of land bearing capacity for livestock manure in Shandong Province. As for the spatial characteristics, the pollution risks of livestock and poultry manure in different districts were quite different; the values of I for N and P were all less than 1 in the cities of Qingdao, Zibo, Liaocheng, and Heze, thereby indicating that the land consumption of livestock and poultry manure was not overloaded in these cities. The values of I for N and P in the cities of Jinan, Zaozhuang, Yantai, Tai''an, Weihai, Rizhao, Laiwu, Linyi, and Dezhou were all greater than 1. The higher values of I for N and P in these areas revealed that the livestock and poultry manure exceeded the farmland''s bearing capacity and that high risks of livestock and poultry manure pollution existed. In particular, the I values for N and P in Laiwu City were 2.14 and 2.36, respectively, thereby showing a high risk of pollution in farmlands. The large surplus of nutrients from livestock and poultry manure greatly exceeded the carrying capacity of agricultural land and would result in N and P pollution. From a time series perspective, the overall breeding scale had generally increased in Shandong Province in the past ten years, and had increased from 7.042×10⁷ to 8.401×10⁷ pigs. Especially from 2009 to 2012, the overall scale increased greatly by 13.3%. The crop demands of N and P nutrients from manure increased each year by an overall increment of 10.6% and 13.1%, respectively. The N and P nutrient supplies from livestock and poultry manure showed an increasing trend with increments of 8.9% and 2.9%, respectively. In 2016, the land bearing capacity for livestock and poultry manure in Shandong Province reached 8.58×10⁷ and 9.81×10⁷ pig equivalent for N and P, respectively, which were higher than the actual breeding scale of 8.40×10⁷ pig equivalent. The I index of land bearing capacity based on the N and P contents of livestock and poultry manure in Shandong Province showed a decreasing trend. The livestock and poultry breeding industries in Shandong Province are mainly distributed in the regions of Dezhou and Weifang in the southwest and middle-south of Shandong Province. The livestock and poultry manure of the cities of Jinan, Zaozhuang, Yantai, Tai''an, Weihai, Rizhao, Laiwu, Linyi, and Dezhou all exceed the farmland''s bearing capacity. These areas have a potential risk of N and P pollution. Based on the values of the index of land bearing capacity for livestock and poultry manure, there is still potential for farmland to dispose of livestock and poultry manure in some cities of Shandong Province.