Element loss on rain forest conversion in East Amazonia: comparison of balances of stores and fluxes
Element loss on rain forest conversion in East Amazonia: comparison of balances of stores and fluxes
复制标题
东亚马逊雨林转变的元素损失：储存量和通量平衡的比较
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
H. Fölster
中科院分区：
文献类型：
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作者：
R. Klinge;A.R. Araujo Martins;J. Mackensen;H. Fölster
通过比较干扰前后的养分储量，以及测量干扰期间的养分通量，可以估算森林生态系统因燃烧和淋失造成的养分损失。我们将这两种方法应用于亚马逊东部贝伦附近的采伐试验，时间序列正确，持续时间为15个月。养分通量测量包括木材出口、燃烧到大气中的损失和淋溶。后者是基于土壤水分模型的水通量模拟和土壤水提取物的元素分析(陶瓷杯蒸渗仪)。将剩余生物量为33和92 t ha−1的两个样地(出口木材后留下的直径为7 cm)与森林对照样地进行了比较。土壤贮藏量和通量平衡在Na、K、Mg和S的情况下符合得很好，在Ca和全P的情况下部分也是一致的。偏差似乎是由土壤贮藏量(主要是C和全N)不稳定但在统计上不显著的变化引起的。土壤参数的空间变异性要求很高的样本重复性，特别是扰动后。通量测量更好，但成本更高。
Nutrient loss from forest ecosystems by burning and leaching can be estimated by comparing nutrient stores before and after the disturbance, and by measuring the nutrient fluxes during disturbance. We applied both methods to a clear cutting experiment near Belem, Eastern Amazon, in a correct time series of 15 months duration. Nutrient flux measurements include wood export, loss to the atmosphere by burning, and leaching. The latter was based on water flux simulation with a soil water model, and on element analysis of soil water extracts (ceramic cup lysimeter). Two plots with 33 and 92 t ha−1 of residual biomass (left after export of wood >7 cm diameter) were compared with a forest control plot. Store and flux balances agreed well in case of Na, K, Mg, and S, and partially also for Ca and total P. Deviations seem to be caused by erratic but statistically not significant variations of the soil stores (mainly C and total N). Spacial variability of soil parameters demand very high sample replication, especially after disturbance. Flux measurements are better but more costly.