Study Of Ecological Environment Impact Of Rice Production In Liaoning Region

As a pillar industry of the national economy,agriculture consumes a lot of resources and energy,and emits a lot of pollutants.Rice as one of the main grain crops,consumes more resources such as chemical fertilizers,pesticides and fresh water because of its production characteristics,which in turn causes some damage to the ecological environment.Therefore,to clarify the use of agricultural resources in rice production and the effects of resource and environment,it is of great significance to the realization of multiple objectives such as agro-environmental friendly,efficient resource utilization,and“control agricultural water consumption,reduce chemical fertilizers and pesticides use,utilize livestock manure,crop straw and agricultural film”.In this paper,300 rice producers in different rice zones in Liaoning region were investigated by the combination of field survey and indoor statistical analysis,and the utilization of chemical fertilizers and pesticides of rice production in each rice zone was analyzed.On this basis,rice production was divided into 3 stages?the rice cultivation stage,the agricultural resources production stage and the raw material extraction stage?,and the inventories of resources,energy consumption and pollutant emissions of life cycle of rice production in each rice zone were established with 1 ton rice as functional unit.Then,the article evaluated the resources and environmental impact potentials of life cycle of rice production in each rice zone,in order to reduce the environmental impacts caused by unreasonable use of agricultural resources such as chemical fertilizers and pesticides in rice production.The main conclusions are as follows:1.There was a difference in the amount of chemical fertilizers applied in various rice cultivation areas and the application amount was generally high.The application amount of chemical fertilizers in each rice zone was as follows:West mountain and hill rice zone(470.59kg·ha^-1)>Liaohe plain rice zone(425.87 kg·ha^-1)>Southeast yellow sea plain rice zone(393.48kg·ha^-1)>East mountain and hill rice zone(345.70 kg·ha^-1).The highest N and K fertilizers application amount were in Liaohe plain rice zone which were 259 and 114.73 kg·ha^-11 and exceeded the upper limits of recommended N and K fertilizers application amount by 40.38%and 16.06%,respectively.The highest P fertilizers application amount was in Southeast yellow sea plain rice zone which was 97.32 kg·ha^-11 and exceeded the upper limit of recommended P fertilizers application amount by 18.62%.2.There was a difference in the amount of pesticides applied in various rice zones and the application amount was generally high.The application amount of pesticides in each rice zone was as follows:West mountain and hill rice zone(19.02 kg·ha^-1)>Liaohe plain rice zone(17.25 kg·ha^-1)>Southeast yellow sea plain rice zone(15.23 kg·ha^-1)>East mountain and hill rice zone(15.18 kg·ha^-1).The highest insecticides and fungicides application amount were in West mountain and hill rice zone,which were 8.62 and 5.95 kg·ha^-1.The highest herbicides application amount was in Southeast yellow sea plain rice zone which was 97.32 kg·ha^-1.3.There was a difference in the irrigation amount in various rice zones and the irrigation amount was generally high.The irrigation amount in each rice zone was as follows:Liaohe plain rice zone(16937.67 m³·ha^-1)>West mountain and hill rice zone(14311.00 m³·ha^-1)>East mountain and hill rice zone(11655.97 m³·ha^-1)>Southeast yellow sea plain rice zone(7101.96m³·ha^-1).The irrigation amount in Liaohe plain rice zone was the largest,exceeding 88.2%of that in Liaoning,and the irrigation amount in Southeast yellow sea plain rice zone was the least,accounting for 78.91%of that in Liaoning.4.The comprehensive environmental impacts in each rice zone were different,and the environmental impacts varied according to regions.The comprehensive environmental impact index in each rice zone was as follows:West mountain and hill rice zone?4.978?>Liaohe plain rice zone?3.342?>Southeast yellow sea plain rice zone?0.973?>East mountain and hill rice zone?0.742?.The acidification,eutrophication and water toxicity were the most serious in West mountain and hill rice zone whose environmental impact indexes was 0.02,0.13 and4.65,respectively.The energy consumption,global warming,soil toxicity and human toxicity were the most serious in Liaohe plain rice zone whose environmental impact indexes were0.00042,0.00043,0.101 and 0.091,respectively.5.The environmental impacts of different stages were different,and varied from zone to zone.The environmental impact of each stage was as follows:the rice cultivation stage>the raw material extraction stage>the agricultural resources production stage.The environmental impacts of the rice cultivation stage and the agricultural resources production stage were the most serious in West mountain and hill rice zone whose environmental impact indexes were4.87 and 0.025,respectively.The environmental impact of the raw material extraction stage was the most serious in Liaohe plain rice zone whose environmental impact index was 0.11.6.According to the results of the evaluation in each rice zone,the severity of environmental impacts were as follows:water toxicity>eutrophication>soil toxicity>human toxicity>acidification>global warming>energy consumption.