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Reference Category Journals
DOI 10.1002/rra.2853
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Title (Primary) Ecosystem management along ephemeral rivers: trading off socio-economic water supply and vegetation conservation under flood regime uncertainty
Author Arnold, S.; Attinger, S.; Frank, K. ORCID logo ; Baxter, P.; Possingham, H.; Hildebrandt, A.
Source Titel River Research and Applications
Year 2016
Department OESA; CHS
Volume 32
Issue 3
Page From 219
Page To 233
Language englisch
Keywords ecohydrology; info-gap decision theory; species coexistence; robust decision making; arid; Tamarix usneoides; Acacia erioloba; Faidherbia albida
UFZ wide themes RU5;
Abstract In ecosystems driven by water availability, plant community dynamics depend on complex interactions between vegetation, hydrology, and human water resources use. Along ephemeral rivers—where water availability is erratic—vegetation and people are particularly vulnerable to changes in each other's water use. Sensible management requires that water supply be maintained for people, while preserving ecosystem health. Meeting such requirements is challenging because of the unpredictable water availability. We applied information gap decision theory to an ecohydrological system model of the Kuiseb River environment in Namibia. Our aim was to identify the robustness of ecosystem and water management strategies to uncertainties in future flood regimes along ephemeral rivers. We evaluated the trade-offs between alternative performance criteria and their robustness to uncertainty to account for both (i) human demands for water supply and (ii) reducing the risk of species extinction caused by water mining. Increasing uncertainty of flood regime parameters reduced the performance under both objectives. Remarkably, the ecological objective (species coexistence) was more sensitive to uncertainty than the water supply objective. However, within each objective, the relative performance of different management strategies was insensitive to uncertainty. The ‘best’ management strategy was one that is tuned to the competitive species interactions in the Kuiseb environment. It regulates the biomass of the strongest competitor and, thus, at the same time decreases transpiration, thereby increasing groundwater storage and reducing pressure on less dominant species. This robust mutually acceptable strategy enables species persistence without markedly reducing the water supply for humans. This study emphasises the utility of ecohydrological models for resource management of water-controlled ecosystems. Although trade-offs were identified between alternative performance criteria and their robustness to uncertain future flood regimes, management strategies were identified that help to secure an ecologically sustainable water supply.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=15490
Arnold, S., Attinger, S., Frank, K., Baxter, P., Possingham, H., Hildebrandt, A. (2016):
Ecosystem management along ephemeral rivers: trading off socio-economic water supply and vegetation conservation under flood regime uncertainty
River Res. Appl. 32 (3), 219 - 233 10.1002/rra.2853