The Research Of Changes In Vegetable Greenhouse Use And Effects On Soil Environment In Shouguang

With the rapid development of national economy and the growing demand for vegetable,the vegetable industry has entered a new stage of rapid growth since our country decided toimplement the “Vegetable Basket Project”. Therefore, ascertaining the area and changes ofvegetable greenhouse is necessary, and in the meanwhile contrasting the discrepancy betweenhorticulture and common farmland can provide the scientific basis for increasing of soilfertility and producing the pollution-free agriculture produce. These results have referencevalue for the optimum location of vegetable greenhouse and the reducing the negative impactsto achieve the horticulture sustainable development.Taking Shouguang as the research area, this paper analyzed the characteristics ofvegetable greenhouse use temporal and spatial evolution in Shouguang between the year of2003and2009. On this basis, the paper conducted a systematic study of the soil PH, nutritioncontents and heavy metal contents effected by the different soil depth and the planting yearsafter analyzing the available soil data. In the end, it put forward countermeasures accordinglyfor the healthy development of horticulture. The main conclusions in this paper are as follows:(1) In2009, there are0.75%,85.04%and14.21%of the total area of vegetablegreenhouse which are multi-span greenhouse, solar greenhouse and plastic greenhouse. Thespatial distribution of Shouguang horticulture is the southern towns area of more, the northerntowns area of less. The rangeability of vegetable greenhouse is79.46%between the year of2003and2009. The vegetable greenhouse acreage of all towns is incremental exceptShengcheng subdistrict which is decreasing. The vegetable greenhouse of Shouguang hasbeen increasing by13.27%speed every year between2003and2009, which belongs to theslow change type. The change of Shengcheng horticulture belongs to the very slow changetype, while the towns of Wenjia, Hualong, Taitou, Tianliu, Shangkou, Houzhen and Jitaibelong to the rapid changes type, and the other towns are the slow changes type. The proportion of vegetable greenhouse to cultivated land is from13.58%in2003to24.73%in2009. The spatial distribution of the proportion accord with the Thunen Ring Theory, thatcentered on the Shengcheng street, the proportion of vegetable greenhouse to cultivated landdecreases as the distance from the center increases.(2) The PH values of cultivated land plunge that is fluctuated with the expansion ofvegetable greenhouse, while the organic matter, total nitrogen and Olsen-K values ascend, theregularity of Olsen-P values is poor. The variation of the soil PH and nutrient indicatorsbetween solar greenhouses and common farmland is significant. The organic matter, totalnitrogen and Olsen-K values augment while the PH value declines with the increase of soildepth. The Olsen-P maximizes in10-20cm. The values of PH and nutrient indicators can beinfluenced by the different planting years. It is significant for the variation of soil Zn, Cu, Cr,Pb and As in different agricultural land use types. The soil Zn, Cu and Cr maximize invegetable greenhouse while the Pb and As maximize in natural soil. The heavy metalscontents of Zn, Cu, Cr, As in vegetable greenhouse are higher than that in common farmland.(3) This paper points out the factors that restric the sustainable development ofShouguang horticulture, which include the small scale of greenhouse, the low degree ofmechanization, the issue of soil quality and the feeble support of science and technology. Andthen it put forward the corresponding suggestions based on this.