Carbon dioxide transfer over a Central Amazonian rain forest
Carbon dioxide transfer over a Central Amazonian rain forest
复制标题
DOI：
10.1029/98jd02647
复制
发表时间：
1998-12-27
影响因子：
4.4
通讯作者：
Scott, S
中科院分区：
文献类型：
--
作者：
Malhi, Y;Nobre, AD;Scott, S
热带雨林是最重要且监测最少的陆地生态系统之一。近年来，它们对大气中二氧化碳和水蒸气浓度的影响已成为许多猜测的主题。在这里，我们展示了为期一年的二氧化碳通量研究的结果。在亚马逊流域中部的热带森林中，利用涡流协方差微气象技术。二氧化碳通量的昼夜循环与之前热带雨林的短期研究一致，这意味着亚马逊雨林在整体生态生理特征上表现出相当程度的空间均匀性。典型的白天峰值光合作用速率为24-28 μmol CO2 m(-2) s(-1)，呼吸速率为6-8 μmol CO2 m(-1) s(-1)。全年光合作用高峰期具有明显的季节性，与土壤含水量密切相关。另一方面，没有证据表明土壤呼吸具有很强的季节性。亚马逊流域中部只有短暂的 3 个月的旱季，这在热带雨林中并不罕见，因此亚马逊流域大片地区的光合作用能力可能表现出明显的季节性。计算得出初级总产量为30 t C ha(-1) yr(-1)。附录中包含数据质量分析。
Tropical rain forests are among the most important and least monitored of terrestrial ecosystems. In recent years, their influence on atmospheric concentrations of carbon dioxide and water vapor has become the subject of much speculation. Here we present results from a yearlong study of CO2 fluxes. at a tropical forest in central Amazonia, using the micrometeorological technique of eddy covariance. The diurnal cycle of CO2 flux was consistent with previous shortterm studies in tropical rain forests, implying that the Amazonian rain forest shows a fair degree of spatial uniformity in bulk ecophysiological characteristics. Typical peak daytime photosynthesis rates were 24-28 mu mol CO2 m(-2) s(-1), and respiration rates were 6-8 mu mol CO2 m(-1) s(-1). There was significant seasonality in peak photosynthesis over the year, which appeared strongly correlated with soil moisture content. On the other hand, there was no evidence of strong seasonality in soil respiration. Central Amazonia has only a short, 3 month dry season, not atypical of tropical rain forest, and it is therefore likely that large areas of Amazonia exhibit significant seasonality in photosynthetic capacity. The gross primary production was calculated to be 30 t C ha(-1) yr(-1). An analysis of data quality is included in the appendix.