Effects of water loss on primary production: A landscape-scale model
Effects of water loss on primary production: A landscape-scale model
复制标题
水损失对初级生产的影响：景观尺度模型
DOI：
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发表时间：
2004
期刊：
影响因子：
2.4
通讯作者：
Jr. Jeremy B. Jones
中科院分区：
文献类型：
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作者：
E. Stanley;S. Fisher;Jr. Jeremy B. Jones
摘要：河流生态系统的水流失对初级生产者有着深远的影响。关于藻类对干燥反应的少量文献强调了抗干燥机制、再润湿后代谢活动的恢复以及小空间尺度。不幸的是，由于各个流域内的干燥水文模式和生态过程都存在高度可变性，因此小规模模式很难解释。因此，最好在更大的空间尺度上检查干燥的影响，因为在较小尺度上出现的随机变化会被纳入整个流域更大、更可预测的模式中。我们提出了一个适用于整个流域规模的水流失对初级生产者影响的概念模型。这种观点描述了对水流失的敏感性的差异，以及作为流域内位置函数的初级生产下降和恢复率的差异。通过将溪流视为在空间和时间上斑驳的、相互关联的景观，并认识到扰动在空间上的明确影响，将有助于未来对初级生产等生态系统属性的干燥问题的考虑。不同地区的河流在干旱的发生、地球物理模板和响应变量（存在的生物体类型及其集体代谢）方面可能存在很大差异。当今干旱研究的挑战是确定哪些现象是普遍且广泛应用的，哪些现象是特定地区特有的。
Abstract.Water loss from stream ecosystems has profound effects on primary producers. The small body of literature on algal responses to desiccation has emphasized mechanisms of resistance to desiccation, recovery of metabolic activity upon rewetting, and small spatial scales. Unfortunately, small-scale patterns are difficult to interpret because of the high degree of variability in both hydrologic patterns of drying and ecological processes within individual drainage basins. Consequently, effects of drying are best examined at larger spatial scales because variation that appears random at smaller scales become incorporated into larger, more predictable patterns across an entire catchment. We present a conceptual model of the effects of water loss on primary producers applicable to the scale of the entire catchment. This perspective describes differences in susceptibility to water loss, and differential rates of decline and recovery in primary production as a function of location within the catchment. Future considerations of drying on ecosystem attributes such as primary production will be facilitated by treating streams as patchy, interconnected landscapes in space and time and recognizing spatially explicit effects of disturbance. It is likely that streams of different regions vary widely in terms of the occurrence of drought, the geophysical template, and response variables (types of organisms present and their collective metabolism). The challenge in drought research today is to determine what phenomena are general and of widespread application and which are peculiar to given regions.