Prospects for monitoring freshwater ecosystems towards the 2010 targets

Abstract

Human activities have severely affected the condition of freshwater ecosystems worldwide. Physical alteration, habitat loss, water withdrawal, pollution, overexploitation and the introduction of nonnative species all contribute to the decline in freshwater species. Today, freshwater species are, in general, at higher risk of extinction than those in forests, grasslands and coastal ecosystems. For North America alone, the projected extinction rate for freshwater fauna is five times greater than that for terrestrial fauna-a rate comparable to the species loss in tropical rainforest. Because many of these extinctions go unseen, the level of assessment and knowledge of the status and trends of freshwater species are still very poor, with species going extinct before they are even taxonomically classified.Increasing human population growth and achieving the sustainable development targets set forth in 2002 will place even higher demands on the already stressed freshwater ecosystems, unless an integrated approach to managing water for people and ecosystems is implemented by a broad constituency. To inform and implement policies that support an integrated approach to water management, as well as to measure progress in halting the rapid decline in freshwater species, basinlevel indicators describing the condition and threats to freshwater ecosystems and species are required. This paper discusses the extent and quality of data available on the number and size of populations of freshwater species, as well as the change in the extent and condition of natural freshwater habitats. The paper presents indicators that can be applied at multiple scales, highlighting the usefulness of using remote sensing and geographical information systems technologies to fill some of the existing information gaps. Finally, the paper includes an analysis of major data gaps and information needs with respect to freshwater species to measure progress towards the 2010 biodiversity targets.

An inventory of mammals, birds and reptiles along a section of the river and banks of upper Ganges, India

“…However, there is an increasing concern worldwide on the loss of aquatic ecosystems and their associated biodiversity (Georges & Cottingham 2002;Saunders et al 2002;Cullen 2003), particularly for riverine landscapes (Dunn 2004). Rivers and associated freshwater habitats are among the most threatened ecosystems of the world (Revenga et al 2005;WWF 2006) due to a wide range of intensive human use and developmental activities. In addition, declines in biodiversity are far greater in fresh waters than in the most affected terrestrial ecosystems (Sala et al 2000), because inspite of facing varied threats and large scale exploitations, the freshwater hotspots generally receive less management attention than their terrestrial counterparts (Myers et al 2000).…”

Challenges and opportunities for integrating lake ecosystem modelling approaches

“…Another major purpose has been to develop predictive tools supporting inter-disciplinary ecosystem management (Carpenter et al 1999), acknowledging the great importance of lake ecosystems for society (MEA 2005). The ecological quality of lakes is threatened by a large number of anthropogenic stress factors, in particular eutrophication, pollution of various types, overexploitation and invasive species, changes in land use and hydrology in the catchment and climate change (e.g., Gulati and Van Donk 2002;MEA 2005;Mooij et al 2005;Revenga et al 2005;Jeppesen et al 2009;MacKay et al 2009). …”

Quantifying the effect of catchment land use and water nutrient concentrations on freshwater river and stream biodiversity

“…Freshwater species are, in general, at higher risk of extinction than those in terrestrial ecosystems such as forests and grasslands (Sala et al, 2000;Dudgeon et al, 2005;Revenga et al, 2005), and freshwater biodiversity has declined faster than either terrestrial or marine biodiversity over the past 30 years (Jenkins 2003;UNESCO, 2003;Xenopoulos et al, 2005). In North America the rate of species loss in freshwater ecosystems is estimated to be five times greater than that for terrestrial fauna (Revenga et al, 2005). This sensitivity to human-induced biodiversity decline makes freshwater systems such as rivers and streams a suitable study subject in order to gain insights into the rate of global biodiversity loss caused by human influences.…”

“…This sensitivity to human-induced biodiversity decline makes freshwater systems such as rivers and streams a suitable study subject in order to gain insights into the rate of global biodiversity loss caused by human influences. The major factors responsible for this rapid decline in freshwater species are physical alteration, habitat loss, water withdrawal, pollution, overexploitation and the introduction of non-native species (Sala et al, 2000;Millennium Ecosystem Assessment, 2005;Revenga et al, 2005). Habitat alteration is cited as a leading cause of extinction in general, and has contributed to 73% (Miller et al, 1989) of the fish extinctions in North America during the twentieth century (Allan and Flecker, 1993;Sala et al, 2000).…”