Catchment disturbance and stream metabolism: patterns in ecosystem respiration and gross primary production along a gradient of upland soil and vegetation disturbance
Catchment disturbance and stream metabolism: patterns in ecosystem respiration and gross primary production along a gradient of upland soil and vegetation disturbance
复制标题
流域扰动和河流代谢：沿着高地土壤和植被扰动梯度的生态系统呼吸和总初级生产模式
DOI：
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发表时间：
2005
影响因子：
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通讯作者：
K. Maloney
中科院分区：
文献类型：
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作者：
J. N. Houser;P. Mulholland;K. Maloney
摘要流域特征决定了河流泥沙和营养物质的输入。因此，对旱地土壤和植被的自然或人为干扰会影响到不稳定过程。本宁堡军事设施（哥伦布附近，格鲁吉亚）表现出广泛的高地干扰水平，因为空间变化的军事训练的强度。这种干扰梯度用于研究旱地土壤和植被干扰对溪流代谢速率（生态系统呼吸速率[ER]和总初级生产率[GPP]）的影响。流代谢测定使用开放系统，单站的方法。所有溪流在所有季节净异养。ER在冬春季最高，夏秋季最低。ER在冬季、春季和夏季与流域干扰水平呈负相关，但在秋季不相关。ER与粗木质残体丰度呈正相关，与底栖有机质含量无显著相关。GPP低，在所有流，一般不显着相关的干扰水平。我们的研究结果表明，这些流的一般完整的河岸带不足以保护他们免受高地干扰的影响，他们强调的作用，整个流域在确定流的结构和功能。
Abstract Catchment characteristics determine the inputs of sediments and nutrients to streams. As a result, natural or anthropogenic disturbance of upland soil and vegetation can affect instream processes. The Fort Benning Military Installation (near Columbus, Georgia) exhibits a wide range of upland disturbance levels because of spatial variability in the intensity of military training. This gradient of disturbance was used to investigate the effect of upland soil and vegetation disturbance on rates of stream metabolism (ecosystem respiration rate [ER] and gross primary production rate [GPP]). Stream metabolism was measured using an open-system, single-station approach. All streams were net heterotrophic during all seasons. ER was highest in winter and spring and lowest in summer and autumn. ER was negatively correlated with catchment disturbance level in winter, spring, and summer, but not in autumn. ER was positively correlated with abundance of coarse woody debris, but not significantly related to % benthic organic matter. GPP was low in all streams and generally not significantly correlated with disturbance level. Our results suggest that the generally intact riparian zones of these streams were not sufficient to protect them from the effect of upland disturbance, and they emphasize the role of the entire catchment in determining stream structure and function.