The Life Cycle Assessment Of Corn Production To The Environmental Influence Of Shanxi Province

At present, our country is facing the double pressures from the food security and environmental pollution, so it is important for us to ensure food security and reduce the harm of environmental pollution. Shanxi Province is one of the main place of maize origin of our country, discussing of improving the maize yields and reducing the pollution of the environment has scientific significance. This paper research the corn which is one of the main food crops, for Shanxi province’s maize production system as an example. As the questionnaires from the 297 farmers of 99 counties about the process of maize planting and the meteorological data, soil data during of Shanxi 2013 as the basic data. Adopt the life cycle assessment and DNDC model to jointly establish the list of resource consumption and environmental pollutant emissions inventory about life cycle of maize production in Shanxi. Corn production It as the basic unit of the life cycle assessment, and the life cycle is divided into three stages:raw materials stage, agricultural materials and agronomic phase stage. Shanxi Province three regions Jinnan, Jinzhong, Shanxi Province, due to the different climate, soil, corn Life Cycle Environmental Impact Assessment under cropland management measures. Discuss the potential of environmental influence and the main factor about the three regions, the results of analysis:(1) During the process of corn planting, the nitrogenous fertilizer quantity into the field decreasing from south to north in Shanxi 2013, the southern Shanxi> Jinzhong> the northern Shanxi, especially the Yuncheng which is part of the area in southern Shanxi up to 573.93 kg·ha-1, North Shanxi is low in 300 kg·ha-1, the average nitrogen inputs is 406.88 kg-ha-1. The high fertilizer inputs results in a large number of emissions from environmental contaminant.(2) The impact degree to environmental of the resource factors during the procedure maize life cycle production followed by eutrophication, acidification, land using, global warming and energy consumption, the numeric is 0.55,0.51,0.21,0.09,0.06. And the impact degree to environmental is in order to reduce from south to north, as is the southern Shanxi> Jinzhong> the northern Shanxi. In the area of southern Shanxi and Jinzhong, the main environmental impact factor is eutrophication, the northern Shanxi is acidification.The comprehensive index of the environmental impact sort is the southern Shanxi > Jinzhong> the northern Shanxi, the numeric is 0.069 0.061 and 0.059.(3) Different methods of applying fertilizers can bring different environmental impacts in the same area. Applying fertilizers on the face of the field is greater than the applied area of applying fertilizers to the hole. For example,the Xiaxian and Wenxi belong to the south of Shanxi ,which the quantities of fertilizers are 600 kg-ha-1. But Xiaxian is applying fertilizers on the face of the field,Wenxi is applying fertilizers to the hole. At the comprehensive environmental impact potential index, Xiaxian is 0.57, Wenxi is 0.43.(4) This paper main research three factors:the corn yield, the quantity and pattern of nitrogen fertilizer. Using a lot of nitrogen fertilizer makes NH3 volatilize lead to eutrophication and acidification of the environment, so not only to reduce the amount of nitrogen fertilizer, but also change the way of nitrogen fertilizer to improve the environment. An important method of reducing environmental pollution is to make use of the nitrogen fertilizer, while reducing the amount of nitrogen fertilizer.