Effects Of Maize And Vegetables Intercropping Patterns On Soil Character In The Vegetables Field

The effects on soil microbial prosperities and soil physical and chemical characters and vegetable yield were studied under different intercropping pattern treatments of vegetables and maize,with sole cropping and bare land as a contrast. And the differcecn of nutrient content and biological activity in soil under different vegetable straw returning and allelopathic of straws extract on the vegetables seeds were studied too. The aim was to clarify the relationships between soil nutrients and soil organism and soil environment,and to supply academic base for solving continuous cropping obstacle and summer fallow problems in vegetable field.1. Difference of soil properties under different intercropping patternSoil total N content and soil urease activity were significantly decreased under vegetable continuous cropping than that in control, and especially the decreasing range of soil total nitrogen content and soil urease activity in two crops of broccolis in one year is largest, that results indicated that planting mode of two crops of broccolis in one year had caused soil nitrogen overly consumption and a partial lack of soil nutrient. Relay cropping mode of maize/vegetables taken advantage of soil nitrogen in different soil layer,and avoid the excessive consumption of soil nitrogen in shallow soil, and it ensured that soil total nitrogen content and soil urease activity on a high level.2. Difference of using nutrient and yield under different intercropping patternIntercropping or relay cropping could decreased the inorganic nitrogen concentration, and increase the N utilizing rate by 14% in vegetable fields compared with sole cropping. The result indicated that the glutinous maize under relay-intercropping had a higher partial land equivalent ratio, and had a significantly advantage in increasing yield. But because of intercropping green string bean lower then sole cropping green string bean, the intercropping system of maize and green string bean had a lower yield. The growth of the relay-intercropping broccoli was smaller and flowering later at the earlier development stage, but was accelerated at the later stage. There was no significant difference between sole cropping broccoli and relay-intercropping in yield. The yield of glutinous maize/broccoli relay-intercropping system increased by 12%.3. Differcecn of nutrient content and Biological Activity in soil under different vegetable straw returning The calculated results showed that Calcium Cyanamide in middle concentration can increase the content of soil organic matter and soil total nitrogen and soil ammonium nitrogen. But, Calcium Cyanamide in high concentration can improve soil pH value,and decreased the content of soil nitrate nitrogen. The results indicate that Calcium Cyanamide in middle concentration formed a soil environment where were beneficial to soil biological self reproducing and to accelerate metabolism of soil organisms,and it was favorable to decaying straw and releasing nutrient, but Calcium Cyanamide in high concentration could enhance pH value and the soil nitrification was inhibited. cucumber straw had an advantage in increasing supply of organic matter and total nitrogen and improving soil biological environment compared with potato straw and tomato straw. The combination of CaN60 and cucumber straw showed a best effect in improving soil environment at the late stage of the cucumber.4. Allelopathic of straws extract on the vegetables seedsThe straws extract of the vegetables significantly affected the germination rate of vegetables seed and the inhibition effect was raised with the concentration reasing. The straws extract of glutinous maize had a lower effect on germination rate of vegetables seed compared with the other vegetables straws extract, it showed that glutinous maize was a better crop planed before vegetables or straws returning in vegetables field. In addition, the vegetables straws extract had a higher inhibition effect on germination rate of the smaller particle seed than the bigger one.When vegetables seeding was dealt with different concentrations and concentration of straws extract,MDA and POD activity were increased, protein content and root activity were decreased. The yield of the seeding was significantly decreased under the alkaline and neutral component, and that had a higher inhibition effect on stem and leaf than root.