森林生态系统稳定性的养分原理

从森林组分的易变性、对干扰的反作用、养分的储备及其流动规律等角度,分析了森林生态系统稳定性的原理,并对刺槐(R obin ia p seud oacacia)、兴安落叶松(L arix gm elin ii)、油松(P inus tabu laef orm is)和杉木(Cunn ingham ia lanceola ta)4种人工林进行了典型分析。结果表明,这4种人工林的养分均以钝性储备为主,土壤中的N,P,K,C a和M g养分贮量占整个系统对应养分总贮量的比例均大于92%,而且土壤养分均基本保持平衡或发生微弱亏损(年亏损率0.046%~0.121%),而整个生态系统的养分均基本保持平衡或发生微弱盈余(年盈余率0.005%~0.016%);与其他人工林相比,刺槐人工林为高吸收、高归还、快速循环、养分浪费型(较低养分生产力),其养分流速明显高于其他林地,预示刺槐林在面对微小干扰时具有较强的恢复力,但面对严重的干扰时其恢复力较差。同时作者提出,进行生物地球化学分类是研究森林生态系统功能稳定性的重要途径。

Nutritional principle of forest ecosystem stability

Principles of forest ecosystem stability are fully analyzed and discussed from the angle of changeability of ecological components,reaction to disturbance,pattern of nutrients storage and flux and recycle of nutrients in forests.Meanwhile,four artificial forest ecosystems,including Robinia pseudoacacia,Larix gmelinii,Pinus tabulaeformis and Cunninghamia lanceolata,are studied typically about their nutritional conditions and stabilities.It shows that the four forest ecosystems take obtuse form as their main storage of nutrient.The amounts of N,P,K,Ca and Mg stored in soil take up more than 92% respectively of the responding storages of the total forest ecosystem.Further more,the nutrients in the soil retains balance or show slight deficit,whereas,the nutrients in the total forest ecosystems happen to slight surplus or retain balance.In addition,compared with others,the forest of R.pseudoacacia is one of high nutrient absorption,high returning,fast recycling and nutrient wasting,and due to the faster recycling of nutrient,the forest of R.pseudoacacia will have strong capability of restoration in case of minimal disturbance but be irretrievable under serious disturbance.Finally it is suggested that the biogeochemical classification of forests would be an important approach to study the functional stability of forest ecosystem.