An improved method used for evaluating potential environmental pollution risk based on spatial distribution and density of farms

Evaluation of the local decoupling of livestock and cropland in the Huang-Huai-Hai region

Decoupling livestock and cropland production at regional scale have poor resource-use efficiency and detrimental effects on environment in China. It is therefore necessary to identify the decoupled livestock and cropland production system and make recommendations to recouple livestock and cropland. This study used the indexes of land carrying capacity (LCC), animal manure absorption capacity (AMAC), and risk warning value (R) to evaluate the coupling between cropland and livestock at the local scale in the Huang-Huai-Hai region. The decoupling of cropland and livestock in the case of Beijing (SY_BJ) was found assessed with lower theoretical value of LCC and higher theoretical value of AMAC compared with local actual situation, categorized as grade IV with a high R value (above 1). Contrary results were found that the livestock and cropland production systems were coupled at the local scale in the cases located in Hebei and Shandong Provinces, categorized as grade I or II. Two measures were used to optimize the decoupled case by adjusting the ratio of manure to fertilization or reducing breeding quantity. The decoupled case of SY_BJ could be optimized by adjusting the ratio of manure to fertilization (95.34% based on nitrogen and 81.97% based on phosphorus, respectively). The breeding quantity in this case should be reduced by at least 46% to recouple the livestock and cropland at the local level to manage nutrient surpluses from livestock and poultry breeding.

A Transportation Network Optimization Model for Livestock Manure under Different Terrains Considering Economic and Environmental Benefits

Optimizing the path of livestock manure used for farmland is a hugely significant issue, which not only improves the utilization efficiency of manure but also reduces the cost of the transportation of manure. However, some factors such as different terrains and the density of surrounding farmland may lead to more difficulty in further improving the resource utilization rate. Therefore, this paper aims to establish a transport network optimization model for a complex livestock manure distribution scheme. Using basic information from livestock and poultry farms, cultivated land, water areas and forestland in Xinzhou District, Wuhan City, Hubei Province, the relationship between farmland and livestock farms is divided into farm-intensive and water-intensive farmland areas by using the Voronoi diagram subdivision method. Then, according to the supply–demand balance of manure and crop demand, an optimization model is proposed to discuss the manure return scheme for these two types of terrain. The results show that our model can help significantly improve manure utilization efficiency under different terrain situations, which is proposed comprehensively, considering the economic and environmental benefits.

Spatial Suitability Evaluation of Livestock and Poultry Breeding: A Case Study in Wangkui County, Heilongjiang Province, China

With the development of animal husbandry, environmental pollution caused by livestock and poultry breeding (LPB) has become a major problem faced by environmental protection departments. In response to this problem, this study established a spatial suitability evaluation system for LPB. According to the particularity of the indicators, there is a nonlinear relationship after quantification and not all elements in the matrix presented by the indexes and evaluation units have an ‘order’ relationship. Therefore, this study selects a method of combining a self-organising map network. The Hasse diagram technique and geographic information system were used to evaluate the suitability of LPB. Practical application research was conducted in Wangkui County. Most regions of Wangkui County are unsuitable for LPB, accounting for 81.23% of the total area of the county. A small part of a suitable region (434.76 km2) was determined to be a potential site for LPB. According to the results of suitable breeding regions, 17 existing large-scale livestock and poultry farms (LPFs) with unreasonable distribution were optimised for space, which are located in an urban construction area. Spatial optimisation was performed using GIS buffer and overlay analyses, providing the best relocation plot for these 17 LPFs. The results provide a scientific basis for the utilisation of livestock manure and spatial layout planning for LPB.

Evaluation index system design and coordinated development analysis for the industrial green development system and regional non-waste system in the Yangtze River Economic Zone

Based on the research background of the new economic norm and the construction of "non-waste city" in China, this paper studies the coordinated development between the industrial green development system and the regional "non-waste" system of the Yangtze River Economic Zone. First, using the data from 11 provinces from 2013 to 2017 as samples, the comprehensive evaluation index systems for the industrial green development system and the regional "non-waste" system are constructed, respectively. Then, considering the multi-source heterogeneous characteristics of the evaluation index data, the two-tuple linguistic entropy weight method, and gray relational analysis method are applied to filter the evaluation indexes and determine the index weights respectively. Third, combined with the dynamic TOPSIS idea, a new improved coupling coordination degree model is proposed to study the coordination development between the two systems. Finally, an empirical analysis is made, and the result shows that the overall degree of coupling coordination of the two systems shows a fluctuating upward trend. Moreover, the provinces are mainly low-level coupling coordination, and the factors that are hindered in various regions are different.