Effect Of Paddy-Upland Crop Rotation On Soil Properties Under Continuous Tomato Cropping In Greenhouse

In this paper, we chose years of tomato continuous cropping soil in greenhouse for research to study the influence of high intensity successive plantation and growing rice and field Irrigation to the properties of tomato continuous cropping soil. We analyzed the change characteristics of soil microbial quantity and diversity, soil enzyme activity, soil nutrient, soil ion, heavy metal and microelement over time. The analysis results as follows: 1. The influence of high intensity successive tomato plantation to soil properties.(1) High intensity greenhouse plantation made the soil microbial quantity significantly higher than that of field and Yangqi ground, in which bacteria was higher by 49.02% and 149.06%, fungi was higher by 47.66% and 241.57%, actinomycetes was higher by 120.90% and 510.94%, and increased the richness of bacterial community.(2) High intensity greenhouse plantation had the most impact on protease and dehydrogenates. In 0-20cm, greenhouse protease activity was lower by 84.51% and 80.53%, dehydrogenates was higher by 96.73% and 129.17%.(3) High intensity plantation resulted in accumulation of soil nutrients, which was significantly different to Yangqi ground and field.(4) High intensity greenhouse plantation resulted in the accumulation of K+、Ca2+、HCO3-, which was respectively higher than that in Yangqi ground and field by 700% and 700%,56.25% and 64.47%,136.36% and 100.00%. Ion was mainly accumulated in the soil between 0-20cm.(5) Years of high intensity plantation had most impact on the content of chromium and mercury in soil. In soil layer between 0-20cm, greenhouse cadmium content and the mercury content, which was lower than national standards, were respectively higher than that in Yangqi ground and field by 25.00% and 33.99%,80.95% and 90.00%.(6) High intensity plantation resulted in the substantial accumulation of microelement in the range of 9.07% to 1037.25%. 2. Test to two kinds of rotation pattern:(1) The content of bacteria and actinomycetes of steeping field had the biggest decline, 107.98% and 684.91%, in the two patterns.Field Irrigation improved the bacterial community diversity. Rice plantation improved the fungi community diversity.(2) Both the two treatments could improve the soil activity of invertase, urease, phosphatase and protease, but inhibit the dehydrogenase, in which rice plantation had the most impact on urease, invertase and protease activity, respectively 36.96%,2463.80% and 73.36%. Field Irrigation improved phosphatase activity by 321.43%.(3) Rice plantation and field Irrigation respectively lowered the soil pH by 6.02% and 5.95% between 0-20cm soil layer, EC decreased by 64.13% and 54.78%. Between 20-40cm soil layer, pH and EC also showed a decreasing trend.(4) In two treatments, except carbonate ions, other ions were reduced over time. Rice plantation had the largest decline.(5) Field Irrigation increased the content of available manganese and available iron and reduced the content of available copper and available zinc. Rice plantation increased the content of available iron and reduced the content of available copper and available zinc.