【摘要】 根据马尔可夫链模型,定量地探讨了湖南省洞庭湖区农田生态系统中Cd的迁移转化问题,计算了Cd在土壤-水-稻谷-大气系统中的滞留时间和环境允许量,进而探讨了系统的生态承载力,得到系统中Cd的最大允许排放量CdA与生态承载力M人口之间的关系式:CdA=3.56×10-4M人口,为生态环境地球化学评价提供了一种新的方法和途径。更多还原

【Abstract】 Based on the Markov chain model, we discuss quantitatively the transfer and conversion of Cd element in cultivated areas of the Dongting Lake region, Hunan province, China. We calculate the residence time and environmental capacity of Cd element in the soil-water-paddy-atmosphere system. Furthermore, we discuss the ecology-bearing capacity of the system. We obtain the relationship between the environmental capacity (CdA) of Cd and ecology-bearing capacity (Mpopulation) of the system: CdA=3.56×10-4Mpopulation. This provides a new approach for the geochemistry evaluation of an ecosystem.更多还原