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为了解马尾松人工林不同发育时期的养分动态,利用空间代替时间的方法对7、17、31和51年生4个年龄阶段的马尾松人工林养分积累、分配及循环进行了研究.结果表明:马尾松人工林发育过程中,生物量积累与养分积累具有不同步性,从17年生到51年生,生物量积累增长速率是N、P、K、Ca和Mg积累增长速率的3.3、5.4、3.3、3.7和9.8倍;各器官中养分的分配与养分库增长速率有关,随着林龄的增长,树干养分的比重和养分的根冠比增大;单位养分生产的干物质量随林龄增长而提高,51年生时林分的养分循环系数较高,具有低存留、高归还的特点,养分利用效率最高.缩短轮伐期降低了养分高效利用的机会.为维持林地的长期生产力,建议将马尾松人工林轮伐期延长到50年以上,同时降低收获强度.
In order to understand the nutrient dynamics of Pinus massoniana plantations at different developmental stages, the spatial distribution of time, the nutrient accumulation, distribution and circulation of Pinus massoniana plantations at four age stages of 7, 17, 31 and 51 years were studied.The results showed that: During the development of Pinus massoniana plantation, biomass accumulation and nutrient accumulation were asynchronous. From 17 years to 51 years, biomass accumulation and growth rate was 3.3, 5.4, 3.3 of accumulation rate of N, P, K, Ca and Mg , 3.7 and 9.8 times respectively. The distribution of nutrients in various organs was related to the growth rate of nutrient pool. With the increase of forest age, the proportion of trunk nutrients and root / shoot ratio of nutrients increased. The dry matter mass per unit nutrient production increased with age Improve the nutrient cycling efficiency of the stand at 51 years old is higher, and it has the characteristics of low retention and high return, the highest utilization efficiency of nutrients, shorten the rotation period and reduce the opportunity of efficient use of nutrients.In order to maintain the long-term productivity of woodland, Pine plantation rotation period extended to more than 50 years, while reducing harvest intensity.