The Freshwater Animal Diversity Assessment: an overview of the results

Abstract

We present a summary of the results included in the different treatments in this volume. The diversity and distribution of vertebrates, insects, crustaceans, molluscs and a suite of minor phyla is compared and commented upon. Whereas the available data on vertebrates and some emblematic invertebrate groups such as Odonata (dragonflies and damselflies) allow for a credible assessment, data are deficient for many other groups. This is owing to knowledge gaps, both in geographical coverage of available data and/or lack of taxonomic information. These gaps need to be addressed urgently, either by liberating date from inaccessible repositories or by fostering taxonomic research. A similar effort is required to compile environmental and ecological information in order to enable cross-linking and analysis of these complementary data sets. Only in this way will it be possible to analyse information on freshwater biodiversity for sustainable management and conservation of the world's freshwater resources.

Integrated water resources management of overexploited hydrogeological systems using Object-Oriented Bayesian Networks

“…patterns to the Threat maps, but only considering pollution. Our results are also congruent with 13 previous threat assessments conducted at the coarser drainage basin and ecoregional scales 7 We were unable to compute a global estimate of adjusted BD Threat due to the paucity of 3 relevant data but also the reality that much less comprehensive investment has been directed to 4 BD conservation than to HWS 34,35 . Limited global investment in environmental protection and 5 rehabilitation means that stresses on BD for many locations are beyond control.…”

“…Direct stressors include widespread land cover change, urbanisation, 3 industrialisation, and engineering schemes like reservoirs, irrigation, and interbasin transfers that 4 maximise human access to water 1,5 . The benefits of water provision on economic productivity 2,6 5 are often accompanied by impairment to ecosystems and biodiversity, with potentially grave but 6 unquantified costs 3,7,8 . Devising interventions to reverse these trends, such as conventions to 7 protect aquatic biodiversity 9,10 and ensure the sustainability of water delivery systems 11 , requires 8 frameworks to diagnose the primary threats to water security at a range of spatial scales from 9 local to global.…”

“…19 20 The need to mobilise financial resources to support integrated approaches remains urgent, lest 21 further deterioration of freshwaters becomes the accepted norm 2,34 . Habitat monitoring 24-26 and 22 spatially explicit species inventories 7 are essential in evaluating the success of investments 31,34 23 and detecting the emergence of new challenges. Tradeoffs and difficult choices involving 1 competing stakeholders are already the order of the day 2,3,48 and resolving these dilemmas more 2 effectively requires high resolution spatial approaches that engage policymakers and water 3 managers at scales relevant to their decisions including sub-national administrative units, river 4 basins, and individual stream reaches.…”

Estado de conservación y distribución de la biodiversidad de agua dulce en los Andes tropicales

“…Los ecosistemas de agua dulce ocupan menos del 1% de la supericie global, pero albergan aproximadamente el 10% del total de las especies conocidas y un tercio de las especies de vertebrados (Balian et al 2008). La biodiversidad de estos ecosistemas, además, juega un papel vital en la provisión de recursos para los humanos, incluyendo alimento, forraje, medicinas, además de otros servicios indirectos como el control de inundaciones, iltración de agua, reducción de contaminación, recreación, entre otros (Strayer y Dudgeon 2010, Russi et al 2013.…”

Implications of differences between temperate and tropical freshwater ecosystems for the ecological risk assessment of pesticides

“…In line with this, the number of cladocerans and especially rotifers species in the Afrotropical, Neotropical and Oriental zoogeographic regions appear to be lower than in the Palaearctic and Nearctic zoogeographic regions ( Table 2). The insect classes Chironomidae and Culicidae, both belonging to the insect order Diptera, have a, respectively, higher and lower species diversity in the Palearctic and Nearctic regions compared to the Neotropical, Afrotropical and Oriental regions (Balian et al 2008a; Table 2). Furthermore, it should be noted that a comparison of species diversity between the temperate and tropical zone has often been reported to be biased by the fact that taxonomic expertise and research efforts have centered on temperate regions (Mares 1997;Dudgeon 2000;Balian et al 2008a).…”