Investigation On Planting And Breeding Wastes Amount And Its Utilization Ways In Chengdu City

The agriculture production holds an important position in Chengdu city with large grain acreage and livestock breeding amount. However, it is not clear about how many crop straw and livestock manure were produced every year. To make clear of the total amount of planting and breeding wastes and its utilization way in Chengdu will be of great significance to the control of agriculture non-point source pollution, to the improvement of rural ecological environment and to the construction of resource-saving and environment friendly agriculture production system. Accordingly, this thesis makes a survey on the amount of planting and breeding wastes and it utilization ways in Chengdu to get the resource amount of main crop straw and livestock manure, and then make an analysis on its areal distribution feature. Further, this thesis conducts analysis on the utilization potential of planting and breeding wastes to evaluate the emergy of various kinds of utilization ways. At last, to analyze its rationality by the emergy ecological footprint theory, and then put forward specific suggestions to the resource utilization of planting and breeding wastes in Chengdu. Main findings are as follows:(1) The feature of crop straw resource in Chengdu is various kinds, large amount and obvious spatial variation. In2011, the total amount of crop straw in Chengdu is3.6136million tons, they are mainly paddy, wheat, corn, bean, potato, cole and peanut. Among them, the amount of paddy and cole crop straw is1.645million tons and0.7323million tons, they separately occupy45.52%and20.26%of the total amount. To see from the distribution feature, Jintang county is the most abundant in straw resource with its straw amount of0.4966million tons which occupies13.74%of the total amount of Chengdu. What’s more, the straw resource amount of Qionglai city and Chongzhou city amount to more than0.4million tons. Those areas with large straw resource amount will be the most potential areas of straw resource utilization in the future.(2) The feature of livestock manure in Chengdu is various kinds, large amount and obvious spatial variation. In2011, the total amount of livestock manure resource in Chengdu is31.566million tons, they are mainly come from pig, cattle, sheep, fowl and rabbit. Among them, manure of pig is the main source of livestock manure which amounts to22.697million tons and occupies71.91%of the total amount of Chengdu. Fowl manure amount ranks the second, but it’s far less than its of pig, it is amount to3.6505million tons. To see from the distribution feature, Qionglai city and Jintang county is the most abundant in livestock manure resource which separately amounts to4.7253million tons and4.241million tons, and occupies14.97%and13.44%of the total amount of Chengdu. In addition, the livestock manure resource amount of Dayi county and Chongzhou city also amount to about3.6million tons. Those areas with large livestock manure amount will be the most potential areas of livestock manure resource utilization in the future.(3) In2011, the resources of planting and breeding wastes in Chengdu were abundant. The amount of planting and breeding wastes in Chengdu is35.1786million tons. According to the distributional features, Qionglai city and Jintang county have the most abundant planting and breeding wastes. They are5.1509million tons and4.7376million tons respectively, which make up14.64%and13.47%of the amount of planting and breeding wastes of Chengdu. The amount of planting and breeding wastes of Chongzhou city, Dayi county and Shuangliu county is at the level of3million tons. The amount of livestock manure is much more than that of crop straw. According to the amount of planting and breeding wastes of Chengdu, the amount of livestock manure is about9times as the amount of crop straw. Hence, the livestock manure is the major part of the planting and breeding wastes in regions.(4) There is huge potential in the utilization of planting and breeding wastes in Chengdu. If all the planting and breeding wastes whose amount was35.1786million tons had been fertilized in2011, it would have theoretically provided10.0294m tons organic matter, in which N, P, K was217kilotons,167.26kilotons, and134.12kilotons respectively. Qionglai city is the place where the planting and breeding wastes contain most organic matter, N,P and K, which is1.4113million tons,31.15kilotons,24.74kilotons and19.97kilotons respectively. If these wastes can be fully utilized as energy source, it can be equivalent to4.9829million tons of standard coal or2.3424559billion liters of methane. Jintang county has the greatest potential in the practice of utilization of planting and breeding wastes, which can be converted into680,300tons of standard coal or326.3418million liters of methane. In addition, planting and breeding wastes could be used as livestock feed and have the potential of mushroom cultivation materials.(5) Through the emergy ecological footprint analysis, energy and fertilizer utilization ways are the main using ways of planting and breeding wastes in Chengdu, the utilization of planting and breeding wastes has been surplus for5years, in which the average value of the ecological surplus of the ways is1.797hm2/person per year. There is huge potential of the practice of resource of planting and breeding wastes in Chengdu. While the present cultivated lands are unable to accept planting and breeding wastes completely, some preferential policies should be made to comprehensively utilize the planting and breeding wastes in different ways.