关键词: 农药过量施用, 水稻生产, 农药环境测算, 外部成本, 环境影响因子

Abstract:

Applying of pesticides can help to save labor costs, inhibit crop pests and diseases and increase the economic benefits in agricultural production. However, excessive application of pesticides not only damages users' health, but also endangers food safety and pollutes the environment. From the perspective of maximizing social benefits and private benefits, the external costs of pesticide over-utilization in rice production was calculated, which includes the loss of pesticide users, consumers of agricultural products and non-target organisms in the environment, by application of the pesticide environment accounting tools (PEA), environmental impact quotient (EIQ) and damage control models. Based on the results, it was estimated for the optimum cost of pesticide application and the cost of over-application. The results show that:(1) Now, it is quite serious for the excessive pesticide application in rice production in China. In 2016, the cost of pesticide application was 225.3 yuan·hm^-2 (at constant 1990 prices), which was respectively 1.45 times and 1.22 times of the optimum society and private pesticide application cost. (2) Since 1990, it was gradually increased and shown an upward trend for the external cost of pesticide application in rice production. From 1990 to 2016, it was increased from 11.2 to 76.7 yuan·hm^-2 for the external cost of pesticide application in rice production, which was increased 5.8 times with 7.3% rate of growth per year. (3) It is inconsistent in quantity and rate of growth for the optimal application of pesticide per hectare under the social and private interests. It was 155.5 and 184.0 yuan·hm^-2, respectively for the optimum application cost of social and private pesticides in 2016, the latter was 18.3% higher than the former. From 1990 to 2016, the gap was increased from 11.0 to 28.5 yuan·hm^-2 between the pesticide best society application costs and the best private application costs. The growth rate of the optimum dosage for private farmer was faster than for the society. Therefore, the public sector should reasonably regulate the production of highly toxic pesticides, develop low-toxic pesticides and biological pesticides, strengthen the training of pesticide application technologies, promote the socialized prevention and control of crop pests and diseases, strengthen the integrative pest management approach, and vigorously promote the harmful biological comprehensive prevention or physical control measures, so as to solve the problem of excessive pesticide application and reconcile inconsistencies in pesticide application cost.

Key words: excessive pesticide application, rice production, pesticide environmental measurement, external cost, environmental impact factor