Hydrologic Variability Effects on Dryland Ecosystems
D'Odorico, P. and Bhattachan, A. 2012. Hydrologic variability in dryland regions: impacts on ecosystem dynamics and food security. Philosophical Transactions of the Royal Society B 367: 3145-315.
To further explore what might initially have been expected in the way of negative ecosystem consequences due to greater interannual variability of precipitation in dryland ecosystems, D'Odorico and Bhattachan studied "some of the current patterns of hydrologic variability in drylands around the world," reviewing "the major effects of hydrologic fluctuations on ecosystem resilience, maintenance of biodiversity and food security." And what did they find were the real consequences of enhanced hydrologic fluctuations?
The two U.S. researchers report that the preponderance of the investigations they reviewed indicated that random hydrologic fluctuations may actually enhance the resilience of dryland ecosystems by obliterating threshold-like responses to external drivers, and that "by increasing biodiversity and the associated ecosystem redundancy, hydrologic variability can indirectly enhance post-disturbance recovery, i.e., ecosystem resilience." And in the concluding words of their paper, they re-emphasize that dryland ecosystem resilience is "enhanced by environmental variability through the maintenance of relatively high levels of biodiversity, which may allow dryland ecosystems to recover after severe disturbances, including those induced by extreme hydroclimatic events."
Reynolds, J.F., Smith, S.D.M., Lambin, E.F., Turner II, B.L., Mortimore, M., Batterbury, S.P.J., Downing, T.E., Dowlatabadi, H., Fernandez, R.J., Herrick, J.E., Huber-Sannwald, E., Jiang, H., Leemans, R., Lynam, T., Maestre, F.T., Ayarza, M. and Walker, B. 2007. Global desertification: building a science for dryland development. Science 316: 847-851.