Animal community structure as a function of stream size

Abstract

The species-area relationship of the island biogeography theory was calculated for macroinvertebrates in 22 coastal, adjacent streams . A z-value of 0 .19 was obtained . The low z-value was probably a consequence of the short distances between streams as well as high dispersal rates . In addition, a cluster analysis based on the dissimilarity of species assemblages showed that stream size was of prime importance in categorizing the streams . To a smaller extent water quality affected the community structure in the streams .

Contributions of habitat sampling and alkalinity to diatom diversity and distributional patterns in streams: implications for conservation

“…This finding could indicate that dispersal throughout the watershed limits the number of species at a site, and local factors, such as substrata composition and alkalinity, constrain taxonomic complexity of diatom assemblages (e.g., Shannon diversity, evenness, and dominance by a taxon). Sites with larger drainage areas upstream likely have greater species pools than sites located closer to headwater sources, which coincides with the frequently observed trend that larger areas are capable of supporting a greater number of species than smaller areas (Broenmark et al 1984;Rosenzweig 1995). While streams of all sizes need protection from environmental impacts, this finding suggests that smaller headwater streams are of even more conservation value because of their greater sensitivity to loss of species than sites farther downstream.…”

Biological quality of running waters in protected areas: the influence of size and land use

“…For the water compartment, several studies have addressed the relationships between species richness and size of streams, rivers, pools, ponds, lakes and wetlands (Broenmark et al 1984;Ward and Blaustein 1994;Oertli et al 2002), however, to our knowledge, no information is available on the effect of size of protected area on aquatic species richness. Increased size of the protected area may benefit freshwater organisms based on the following considerations: (i) if a protected area is larger, it should be more effective as a buffer zone; (ii) a larger area involves a larger number of streams and inside each stream a larger number of different habitats, thus offering opportunities for a richer freshwater fauna (Vannote et al 1980;Rutt et al 1989;Jeffries 1993;Voelz and McArthur 2000); (iii) according to models developed for terrestrial protected areas (Pickett and Thompson 1978;Shaffer 1981), a larger bulk of water should keep more easily the minimum viable populations of several species.…”

Stable isotope proxies for evaluating biodiversity in stream biota

“…Abundances, species richness and assemblage structures that comprise abundance data of every species such as algae and aquatic insects in streams are also different depending on the same environmental conditions (Jenkins et al, 1984;Brönmark et al, 1984;Ward, 1992;Friberg et al, 1997;Piccolo and Wipfli, 2002;Yoshimura, 2006Yoshimura, , 2007. Thus, the differences in abundance, species richness and assemblage structure of biota in a stream appear to be strongly correlated with the values of ␦ 13 C and ␦ 15 N. For example, the biomass of periphytic algae increases where light is strong, causing a reduction in CO 2 in that specific area.…”