Effect And Evaluation Of Greenhouse Intensive Planting Of Vegetable On Soil Quality

Intensive planting is the main mode of agricultural production nowadays,however after long-term intensive planting,the soil quality may be degraded,such as salt accumulation,soil acidification,and accumulation of heavy metals,and so on.The effect of intensive planting on the greenhouse vegetable soil quality was studied,the soil from Shangsuan Town and Jincheng Town,Jinning District in Kunming city.The amied to provide basis for increasing yield and improving quality,meanwhile enhancement of soil quality.The soil physics,chemistry,biology and pollutant indicators were determined using greenhouse’vegetable soils planting 1~6a and 10~20a fields.Soil quality index and Nemerow comprehensive index method were applied to evaluate soil fertility quality and environmental quality in studied area.The main results are as follows:1,Soil indicators with planting time of 10～20a soils including maximum water holding capacity,conductivity,available potassium,available phosphorus,organic matter,total nitrogen,total phosphorus,total potassium,enzyme activity(alkali phosphatase,urease,catalase)were higher than planting time of 1～6a soils in Shangsuan town.The soil pH values were neutral in Jinning area.The nutrient level was rich,especially the phosphorus content was extremely rich in Jinning area.2.The soil heavy metal contents(total lead,total chromium,total cadmium,total mercury,total arsenic)with the planting timeof 10～20a soils in Shangsuan town were higher than of 1～6a soils,while the soil heavy metals with planting time of 10～20a soils in the Jincheng town were higher than planting time of 1～6a soils,except the total chromium and total mercury.3.The minimum data set(MDS)includes:soil available potassium,available phosphorus,organic matter,total phosphorus,and total potassium.Based on the minimum data set,the SQI with the planting time of 10～20a soil in Shangsuan Town was 0.89,which was higher than the planting time of 1～6a soil;The SQI of Jincheng Townof 10～20a is 0.88,which is lower than 0.91 of planting age of 1～6a.4.The Nemerow comprehensive index withthe planting time of 10～20a soils was 1.18 in Shangsuan town,which was higher than the planting time of 1～6a soils,and reached the lightly polluted line.The Nemerow comprehensive index was 0.65 with both planting times in Jincheng town,which was the level of safety.Overall the Jinning area,the Nemerow comprehensive index with a planting time of 10～20a is higher than planting time of 1～6a,it is 0.91,and reached the warning line.In summary,with the extension of planting years,the study area showed the trend of soil acidification and salinization,and the soil heavy metal content increased,but the phosphorus content in this area was higher,which was related to the phosphate rock in Jinning District.In view of the long-term irrational intensive planting in the region which is cause soil quality degradation,it is recommended to carry out scientific nutrient management.