Context
Water is needed in all aspects of life (article 18.2 of Agenda 21). The biota of freshwater habitats constitutes a large component of overall biodiversity. Recent research (Williams et al. 2004, Biggs et al. 2005) has pointed out that ponds, despite their small size, contribute significantly to the aquatic biodiversity at the regional scale. In comparison to lakes, rivers, streams and ditches, ponds were found to harbour relatively high local species richness (alpha diversity) when sampling is standardized for area. Furthermore, and even more importantly, ponds harbour a significant proportion of the total species richness of plants and macro-invertebrates that are present at larger spatial scales. In the U.K., ponds harbour about 60% of all rare freshwater species. As a result of the high diversity among ponds (beta diversity), these habitats contribute disproportional to regional total species richness (gamma diversity). Among-habitat ecological differences, isolation and chance effects leading to different alternative ecological states, are considered to be key factors promoting the high beta-diversity of pond ecosystems (Scheffer et al. 2005).
The ecological quality of individual ponds seems to be mainly determined by the influence of local land use, because they generally have a small catchment’s area (Declerck et al., 2006; Davies et al., 2008). This implies that adverse land use effects can be mitigated relatively easily by local management. Because of these characteristics, ponds and pools emerge as systems that may allow preservation of a substantial portion of the aquatic diversity in a cost-efficient way.
The project PONDSCAPE conducts research on patterns of biodiversity and ecosystem functions in ponds at multiple spatial scales, and relates these to important factors and processes, such as succession, land use, pollution, pond creation and pond management. The results of these biological investigations will, for the first time, quantify levels of scaling that are relevant to biodiversity. As such, the translation of these results into management strategies is clear.
At the same time, PONDSCAPE will assess the history of the economic and social relevance of ponds for different sectors (agriculture, nature conservation) over the past century and will assess present day perception of these stakeholders with regard to risks and benefits of pond use. Ponds are situated on land owned or managed by these stakeholders and management strategies can only be sustainable if acceptable to these stakeholders.
Based on these research avenues, PONDSCAPE will provide scientifically underpinned recommendations for a sustainable management approach (Göteborg strategy) that will reconcile desires to protect and increase biodiversity levels at various spatial scales (CBD, RAMSAR convention on wetlands, EU Water Framework Directive) with the need to sustain economic activities and ensure economic growth (Lisbon strategy with renewed impetus from the European Council meeting in Brussels 2005). The ultimate aim of PONDSCAPE is to contribute to a sustainable management regime of such water bodies that is acceptable to all stakeholders.