Maximizing water yield with indigenous non-forest vegetation: a New Zealand perspective

Abstract

Provision of clean freshwater is an essential ecosystem service that is under increasing pressure worldwide from a variety of conflicting demands. Water yields differ in relation to land‐cover type. Successful resource management therefore requires accurate information on yields from alternative vegetation types to adequately address concerns regarding water production. Of particular importance are upper watersheds/catchments, regardless of where water is extracted. Research in New Zealand has shown that, when in good condition, indigenous tall tussock grasslands can maximize water yield relative to other vegetation cover types. A long‐term hydrological paired‐catchment study revealed reductions (up to 41% after 22 years) in water yielded annually from an afforested catchment relative to adjacent indigenous grassland. Furthermore, a stable isotope assessment showed that water from fog may substantially contribute to yield in upland tussock grasslands. The tall tussock life‐form and its leaf anatomy and physiology, which minimize transpiration loss, appear to be the differentiating factors. Thus, maintaining dominance of such cover is important for water production, especially in upland catchments. Ecological analogues and integrated land‐use planning are discussed in the context of this essential ecosystem service. Water management programs in other countries are reviewed and that of South Africa is commended as a model.

Hydrologic futures: using scenario analysis to evaluate impacts of forecasted land use change on hydrologic services

“…Hydrologic ecosystem services-such as the availability of water for downstream uses, water quality, and the location and timing of water delivery-can change with increasing demands for surface or groundwater, alterations in the type or amount of surface vegetation, the permeability of soil and other surfaces, and the introduction of contaminants through human activities (DeFries and Eshleman 2004, Foley et al 2005, Brauman et al 2007, Mark and Dickinson 2008.…”

“…Alterations in vegetation can also reduce water availability. In the southern hemisphere, for example, the replacement of native grasslands and shrublands with tree plantations-which is being driven by increasing demands for forest products and by policies and markets encouraging carbon sequestration-can reduce water yields (Farley et al 2005, Mark andDickinson 2008). Reduced water availability may cause or exacerbate local drought conditions, threaten municipal water supplies, diminish the functioning of hydropower plants, and degrade ecosystems (Brauman et al 2007, Buytaert et al 2007, Farley 2007, Harden et al 2009).…”

Changing Perspectives on Managing Biological Invasions: Insights from South Africa and the Working for Water programme

“…The programme ' s name, ' Working for Water ' , captures the dual goals of conserving an important ecosystem service, while simultaneously providing employment for the rural poor. The programme has received international acclaim, and is often cited as an innovative, holistic and successful approach to the management of biological invasions (Hobbs 2004 ;Mark & Dickinson 2008 ;Pejchar & Mooney 2010 ). We review here the perspectives gained during the establishment and implementation of the Working for Water programme over the past 15 years.…”

Modelling the hydrologic response of a mesoscale Andean watershed to changes in land use patterns for environmental planning

“…Many people worldwide are already living in conditions of water scarcity, and with increasing concentration of population in urban areas, future water supply and availability is a globally sensitive issue (Jenerette and Larsen, 2006). Provision of clean water, as an essential ecosystem service, is a crucial factor in watershed/catchments management (Mark and Dickinson, 2008). Land use and climate changes introduce additional complexity in the management Correspondence to: A.…”