Factors governing macrozoobenthic assemblages in perennial springs in north-western Switzerland

Springs are important freshwater habitats that provide refuge for many rare species. In this study, the fauna and abiotic parameters of 20 perennial springs in north-western Switzerland were investigated. Correlation of abiotic and macrozoobenthos data showed that physicochemical parameters had little impact on macrozoobenthic composition, whereas specific substrate parameters strongly influenced the composition of the macrofauna. Surprisingly, nonmetric multidimensional scaling did not reveal a grouping of springs with similar substrate composition or macrozoobenthic assemblages. However, discharge was identified as the factor significantly determining substrate and the composition of macroinvertebrate assemblages. This justifies the hypothesis that, variation in discharge is the disturbance factor governing the macrofaunal composition temporally and spatially within and between patche

A first approach to a faunistic crenon typology based on functional feeding groups

Springs are ecomorphologically and faunistically diverse freshwater ecosystems. Their limnological classification has been afocus of interest since crenic research began. Despite many attempts to include the crenic fauna in the classification of springs, thereis no faunistic crenon typology. Over a three-year period we investigated the macroinvertebrate assemblages and the physical,chemical and ecomorphological conditions of 82 springs in the Swiss Jura Mountains, north-western Switzerland. Based on thesedata we selected the 25 least-disturbed springs to develop a faunistic crenon classification. Based on functional feeding groups wedifferentiated three crenon groups. An analysis of similarities and nonmetric multidimensional scaling for the substratum typessupported the crenon groupings. In general we can distinguish between springs that are dominated by scrapers and characterized bya lotic environment, and those that are mostly inhabited by filtering collectors, associated with a lentic environment. Those twocrenon types are the extremes of a continuum. Particular crenon forms, such as those with extensive carbonate deposits, lie betweenthese extremes. This third group is characterized by gathering collectors and shredders. Using this approach we can distinguishfaunistic crenon types, based on functional feeding groups, which reflect the abiotic conditions within the springs. We provide afoundation for a faunistic crenon typology which now can be tested in other landscapes and will then be applicable to other lowmountain ranges in Europe

Where a springhead becomes a springbrook : a regional zonation of springs

Springs are important freshwater habitats that provide specific abiotic conditions for many species. These conditions may change very rapidly downstream. Limnologists tend to treat spring sources and their adjacent springbrooks as a unity because of the lack of clear criteria to separate these sections. In this study, we investigated the longitudinal distribution of macroinvertebrate assemblages in ten undisturbed springs in north-western Switzerland at three different distances from the source. Using non-metric multidimensional scaling and analysis of similarities, we detected significant differences between the macroinvertebrate assemblages of the investigated sections in all spring ecosystems, even over short distances. These results stress the importance of distinguishing between the sequential habitats in this upper region of headwaters. Although a complex of abiotic factors is responsible for the distribution of macroinvertebrates, we consider temperature to be of special importance. Based on our faunistic data, we propose that the rheocrene-like springs in the Jura Mountains consist of two sections: the springhead and the springbrook, with the springhead consisting of the source and the upper part of the adjacent downstream section. In accordance with literature and our faunistic and temperature data, we place the beginning of the springbrook at approximately 5 m from the springhead. With this distinction, we justify that springheads and springbrooks are unique, discrete ecosystems, and as such must be considered in conservation legislation

Factors governing macrozoobenthic assemblages in perennial springs in north-western Switzerland

Fauna in 20 ausgewählten Quellen der Nordwestschweiz Springs are important freshwater habitats that provide refuge for many rare species. In this study, the fauna and abiotic parameters of 20 perennial springs in north-western Switzerland were investigated. Correlation of abiotic and macrozoobenthos data showed that physicochemical parameters had little impact on macrozoobenthic composition, whereas specific substrate parameters strongly influenced the composition of the macrofauna. Surprisingly, nonmetric multidimensional scaling did not reveal a grouping of springs with similar substrate composition or macrozoobenthic assemblages. However, discharge was identified as the factor significantly determining substrate and the composition of macroinvertebrate assemblages. This justifies the hypothesis that, variation in discharge is the disturbance factor governing the macrofaunal composition temporally and spatially within and between patches

The importance of small water bodies for biodiversity and ecosystem services: implications for policy makers

Small waterbodies, including ponds and small lakes, low-order streams, ditches and springs, are the most numerous freshwater environments globally, are critical for freshwater biodiversity and are increasingly recognised for their role in ecosystem service delivery. Small waters often represent the best remaining examples of intact freshwater habitats and are the most likely to remain unpolluted, often being a refuge for species which have disappeared from larger, more damaged, waterbodies. Practically all water-related ecosystem services are initially mediated by small waters and some, such as carbon cycling, may be dominated by them. Small waters are exposed to all the threats affecting larger waters, and some experienced only by small waters. Despite this, small waters remain the least investigated part of the water environment and are largely excluded from water management planning. We identify the priorities for research to underpin better protection of small waters and recommend policy actions needed to better integrate small waters into the management of catchments and landscapes. The primary requirements are to identify reliable monitoring programmes for small waters, develop effective measures to protect the biodiversity and ecosystem services they provide and ensure that regulators take full account of this critical part of the water environment