论文部分内容阅读
为了探讨加工番茄连作对土壤质量的影响及其障碍机理,分别观测分析了不同连作年限下的土壤理化性质、微生物量及其区系特征,应用综合指数法评价连作对土壤质量的影响。结果表明:随着连作年限的增加,土壤质地变得粘重,土壤砂粒含量下降,粉粒和黏粒含量增加;土壤pH和全盐含量显著增加,有机质、速效钾和速效磷含量持续下降,连作4a后分别下降19.10%、49.11%和80.92%,土壤盐分离子SO42-、HCO3-、Cl-、Ca2+、Mg2+含量呈增加的趋势,Na+、K+含量呈下降趋势;土壤微量元素含量显著降低。土壤微生物总量连作4 a后降低53.95%,其中土壤细菌、放线菌数量显著降低,土壤真菌数量增加。土壤质量综合指数随着连作年限的增加呈幂函数递减。由此可知,土壤连作障碍是土壤质量整体下降的必然结果。
In order to investigate the effect of cropping continuous cropping on soil quality and its obstacle mechanism, soil physical and chemical properties, microbial biomass and its flora characteristics under different continuous cropping years were observed and analyzed. The comprehensive index method was used to evaluate the effect of cropping on soil quality. The results showed that with the increase of continuous cropping years, soil texture became sticky, the content of soil sand decreased, the content of silt and clay increased, the content of soil pH and total salt increased significantly, the content of organic matter, available potassium and available phosphorus decreased continuously, The contents of SO42-, HCO3-, Cl-, Ca2 +, Mg2 + in soil salt ion increased with the increase of 19.10%, 49.11% and 80.92% respectively even after continuous cropping for 4a, while the content of Na + and K + decreased gradually. The contents of soil trace elements decreased significantly. After 4 a continuous cropping, the total amount of soil microorganisms decreased by 53.95%. The amount of soil bacteria, actinomycetes and soil fungi increased significantly. The comprehensive index of soil quality decreased gradually with the increase of continuous cropping years. It can be seen that the continuous cropping obstacle is the inevitable result of the overall decline of soil quality.