Droughts are a major hazard to both natural and human-dominated environments and those, especially of long duration and high intensity, can be highly damaging and leave long-lasting effects. Drought and Aquatic Ecosystems: Effects and Responses describes the climatic conditions that give rise to droughts, and their various forms and chief attributes. Past droughts are described including those that had severe impacts on human societies. As a disturbance, droughts can be thought of as "ramps" in that they usually build slowly and take time to become evident. As precipitation is reduced, flows from catchments into aquatic systems decline. As water declines in water bodies, ecological processes are changed and the biota can be drastically reduced, though species and populations may survive by using refuges. Recovery from drought varies in both rates and in degrees of completeness and may be a function of both refuge availability and connectivity.
For the first time, Drought and Aquatic Ecosystems: Effects and Responses reviews the available rather scattered literature on the impacts of drought on the flora, fauna and ecological processes of aquatic ecosystems ranging from small ponds to lakes and from streams to estuaries. The effects of drought on the biota of standing waters and flowing waters and of temporary waters and perennial systems are described and compared. In addition, the ways in which human activity can exacerbate droughts are outlined. In many parts of the world especially in the mid latitudes, global warming may result in increases in the duration and intensity of droughts.
Acknowledgements
1. Introduction: The Nature of Droughts
2. Types of Drought and their Assessment
3. The Perturbation of Hydrological Drought
4. Droughts of the Past: Dendrochronology and Lake Sediments
5. Water bodies, catchments and the abiotic effects of drought
6. Drought and Temporary Waters
7. Drought, Floodplain Rivers and Wetland Complexes
8. Drought and Perennial Aquatic Systems: Plants and Invertebrates
9. Drought and Fish of Standing and Flowing Waters
10. Estuaries and Drought
11. Human-induced exacerbation of Drought Effects on Aquatic Ecosystems
12. Conclusions
References
Index
Philip "Sam" Lake is an Emeritus Professor in the School of Biological Sciences and a Fellow of the Australian Centre for Biodiversity at Monash University, Melbourne, Australia. Much of his research has focussed on the effects that both natural disturbances (e.g. floods, droughts) and human-generated ones (e.g. pollution, catchment land-use change) have on the biota of freshwater systems. Recently, he has also been investigating the ecological processes involved in the restoration of degraded flowing waters.