论文部分内容阅读
近年来我国地膜施用量及覆盖面积快速增加,在提高农业产量的同时也产生了严重的农膜污染,在西北干旱区的表现尤为突出。论文利用实地采样数据及农户调查数据,建立Probit模型与多元线性回归模型,分析黑河中游绿洲区地膜的残留水平与影响农户地膜施用行为的主要影响因素。结果表明:1)目前张掖市农用地膜覆盖现象已经非常普遍,有69.9%的农作物播种面积覆盖了地膜;2)仅2014年1 a研究区地膜的残留率平均为25.7%;耕地中地膜的残留总量达到了63.75 kg/hm2,相当于2014年单位玉米种植面积的地膜用量,已经接近我国国家标准限定值(75.0 kg/hm2),明显高于内蒙古与华北地区;3)在低温少水的黑河中游山区,农户并未大规模施用地膜进行保温保湿,而是采用种植春小麦与大麦作物应对气候不足。地膜施用与否的高程界线约为2 100 m。从多元线性回归模型的结果来看,农户地块数量和农户的非农工资水平对农户地膜回收率有明显的负面影响,农业劳动投入时间与高程则具有明显的正面影响。从原因上看,农户非农收入水平的高低对地膜回收率具有决定性的影响。值得注意的是,农业补贴与户主的受教育程度对地膜回收率的影响不明显。为提高地膜回收率,减少地膜污染,需要提高地膜质量,防止破碎以便于捡拾;加快地膜回收机械的研发与推广,替代逐步提高的人工费用;加快研发与推广可快速降解的地膜技术。
In recent years, the application of mulching film and its coverage in China have been rapidly increasing, which has also caused serious pollution of agricultural film while increasing agricultural output, especially in the arid areas of northwestern China. Based on the field sampling data and household survey data, Probit model and multivariate linear regression model were established to analyze the residual film level of mulched oasis in the middle reaches of the Heihe River and the main factors affecting the mulching film application. The results showed as follows: 1) At present, the coverage of agricultural land cover in Zhangye City has been very common, with 69.9% of the sown area covered by plastic film; 2) Only 25.7% of the residual film in the study area in 2014 was amassed; The total amount reached 63.75 kg / hm2, which is equivalent to the amount of mulching of corn acreage per unit area in 2014, which is close to the limit value of China’s national standard (75.0 kg / hm2) and significantly higher than that of Inner Mongolia and North China; 3) In the middle reaches of the Heihe River, farmer households did not use large-scale plastic mulch for heat preservation and moisturization. Instead, they used spring wheat and barley crops to cope with climate problems. The limit of application of the film is about 2 100 m. From the results of multivariate linear regression model, the number of peasant land plots and the non-agricultural wage level of peasant households have a significant negative impact on the peasant household mulching film reclamation rate, and the time and elevation of agricultural labor input have obvious positive impacts. From the point of view, the level of non-agricultural income of farmers has a decisive impact on the film recovery rate. It is worth noting that the effect of agricultural subsidies and head-of-household education on plastic film recovery is not obvious. In order to improve the recovery rate of mulching film and reduce the pollution of mulch film, the quality of mulching film needs to be improved so as to prevent it from being broken so as to facilitate picking up. The research and development and promotion of mulching film recovery equipment will be accelerated to replace the gradual increase of labor cost.