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为加强西双版纳地区环境友好胶园的建设,以不同林龄的橡胶林为研究对象,分析橡胶林生长过程中土壤碳氮含量与储量的变化。结果表明:在34年的橡胶种植过程中土壤碳、氮含量与储量均有不同程度的降低,碳分别减少3.33 g kg-1和21.23 t hm-2,氮分别减少0.20 g kg-1和1.3 t hm-2;土壤碳的消耗主要发生在橡胶林种植早期(≤9年林龄),橡胶种植9年以后土壤固碳量逐渐增加,并在21年林龄后达到相对稳定的状态;相比而言,土壤氮含量的降低持续时间较长(3~21年林龄),土壤容重轻微的变化即可对土壤氮储量产生影响,土壤氮储量随时间的变化没有明显的规律性;在1 m深土壤剖面上,土壤碳、氮的变化主要发生在30 cm以上的土层(每层按10 cm计);协方差分析表明,年干胶产量对土壤碳氮含量与储量没有显著影响,但在割胶初期(9年林龄)土壤碳氮含量均明显降低,割胶极有可能引起一些生理生态方面的变化,从而影响土壤的碳氮含量与储量。
In order to strengthen the construction of environment-friendly rubber plantations in Xishuangbanna, the changes of soil carbon and nitrogen contents and reserves during the growth of rubber plantation were analyzed with rubber plantations of different ages as the research object. The results showed that soil carbon and nitrogen contents and their reserves all decreased to some extent after 34 years of rubber planting, with the reduction of 3.33 g kg-1 and 21.23 t hm-2 of carbon, 0.20 g kg-1 and 1.3 g of nitrogen respectively t hm-2. The soil carbon consumption mainly occurred in the early stage of rubber plantation (≤ 9 years old). After 9 years of rubber planting, the soil carbon sequestration gradually increased and reached a relatively stable state after 21 years old. In comparison, the reduction of soil nitrogen content lasts longer (3 ~ 21 years of age) and the slight change of soil bulk density can have an impact on soil nitrogen storage. There is no obvious regularity of soil nitrogen storage over time. The changes of soil carbon and nitrogen in 1 m deep soil profile mainly occurred in the soil layers above 30 cm (10 cm in each layer). Covariance analysis showed that the annual dry glue production had no significant effect on soil carbon and nitrogen contents and reserves However, soil carbon and nitrogen contents decreased significantly in the initial stage of tapping (9 years of age), and it is very likely that some physiological and ecological changes would occur in the process of tapping. As a result, soil carbon and nitrogen contents and reserves were affected.