Search results for "SPECIES RICHNESS"
showing 10 items of 427 documents
Amphibians of the Kayan Mentarang National Park (East Kalimantan, Indonesia): estimating overall and local species richness
2004
On the basis of surveys since 1997 and an intensive survey at the World Wildlife Fund field station at Lalut Birai in 2001, we assessed the importance of the Kayan Mentarang National Park in East Kalimantan for the conservation of Borneo's amphibian fauna. Sixty-five frog species and one Caecilian species are currently known to occur in this region. We report their occurrence in 16 subareas. Most of the species were recorded at Upper Bahau (41) and at the Lalut Birai field station (33). Based on the results of opportunistic searches and transect censuses at Lalut Birai, we argue that the amphibian diversity of the national park is still greatly underestimated.
Dikerogammarus villosus (Sowinsky, 1894) (Crustacea, Amphipoda) colonizes next alpine lake – Lac du Bourget, France
2007
Dikerogammarus villosus has been recorded for the first time in the alpine lake – Lac du Bourget, French Alps. Low abundance of the alien species in gathered samples suggests that the colonization is just in its initial stage. Two native gammarid species: Gammarus fossarum (Koch, 1835) and G. pulex (Linnaeus, 1758) are still present in the lake. The invader has most probably reached the lake through the Canal de Savieres joining the lake to the Rhone River in which it has been already present since late 1990s.
40 Years of Breeding Bird Community Dynamics in a Primeval Temperate Forest (Białowieża National Park, Poland)
2015
We documented the composition and structure of the breeding bird assemblage in the primeval temperate forest of the Bialowieza National Park (BNP), during 2010-2014, and used 40 years of data to assess patterns of its diver- sity. We applied an improved version of the mapping technique (a combined mapping method) for forest birds in seven plots located in three old-growth forest types: ash-alder riverine, oak-hornbeam, and mixed coniferous. The composi- tion of the breeding avifauna and species richness remained basically unchanged. Jointly 67 (79% of 40-year total) breeding species were recorded in 2010-2014. Overall 49 (57%) of all species bred in the study plots in more than 35 years, th…
Determinants and Congruence of Species Richness Patterns across Multiple Taxonomic Groups on a Regional Scale
2012
Applying multiple generalized regression models, we studied spatial patterns in species richness for different taxonomic groups (amphibians, reptiles, grasshoppers, plants, mosses) within the German federal state Rhineland-Palatinate (RP). We aimed (1) to detect their centres of richness, (2) to rate the influence of climatic and land-use parameters on spatial patterns, and (3) to test whether patterns are congruent between taxonomic groups in RP. Centres of species richness differed between taxonomic groups and overall richness was the highest in the valleys of large rivers and in different areas of southern RP. Climatic parameters strongly correlated with richness in all taxa whereas land…
Biodiversity of wood-decay fungi in Italy
2011
Abstract Current knowledge about Italian wood-decay fungi (Basidiomycota and Ascomycota) is surveyed: 1582 taxa belonging to Ascomycota (341) and Basidiomycota (1241) have been reported, including 23 species new to science of Basidiomycota described from Italy within the last five years. Evaluating diversity of wood-decay fungi can provide a more accurate estimation of species richness for fungi which are an important functional component of ecosystems. Aphyllophoroid and Ascomycota species play an important role in habitat conservation and management. Sardinia, Sicily, the Alps and the Apennines are “hot spots” for wood-decay Basidiomycota in Italy.
Comparing the effects of introduced signal crayfish and native noble crayfish on the littoral invertebrate assemblages of boreal lakes
2015
The introduced North American signal crayfish Pacifastacus leniusculus (Dana) has replaced the native noble crayfish (Astacus astacus) in many European freshwaters and can be considered a new component of these ecosystems. The 2 species are apparently similar in many respects, but their ecological equivalence is uncertain and has been little investigated, especially at the whole-lake scale. We compared the effects of the 2 species on the abundance, species richness, and composition of littoral macroinvertebrate assemblages in a set of small- and mediumsized boreal lakes, which included 8 lakes with noble crayfish, 8 lakes with signal crayfish, and 8 lakes without crayfish. We collected semi…
Bacteriophage richness reduces bacterial niche overlap in experimental microcosms
2015
Antagonistic interactions such as competition and predation shape the structure and dynamics of ecological communities. Their combined effects can affect the species richness within a particular trophic level. Despite theory linking the complementarity of interactions across trophic levels and ecosystem functioning, there is a shortage of empirical tests of such predictions. We present an experimental investigation of these combined effects within a bacteria-phage interaction network. We measured the biomass yield of combinations of bacterial strains under increasing levels of bacteriophage richness. Our results show an increasing impact of phage on bacteria with increasing phage diversity.…
Influences of landscape structure on diversity of beetles associated with bracket fungi in Brazilian Atlantic Forest
2015
Abstract Brazilian Atlantic forest ecosystem is a global biodiversity hotspot. We studied the effects of area, connectivity and habitat quality of conservation areas on the diversity of beetles associated with basidiomes of wood-decaying fungi. Moreover, we analyzed the beetles' composition to verify what the process that produces the differentiation between the patches (β diversity). Species richness of fungivorous beetles increased the larger the area and the better the connectivity of conservation areas; however, neither area nor connectivity had an independent effect on beetle richness. Furthermore, the fungivorous beetle community was affected by the reduction in resource availability …
Relationship between soil microarthropod species diversity and plant growth does not change when the system is disturbed
2002
Soil microarthropods influence vital ecosystem processes, such as decomposition and nutrient mineralisation. There is evidence, however, that proper functioning of ecosystems does not require the presence of all its constituent species, and therefore some species can be regarded as functionally redundant. It has been proposed that species redundancy can act as an insurance against unfavourable conditions, and that functionally redundant species may become important when a system has faced a disturbance (the “insurance hypothesis”). We conducted a laboratory microcosm experiment with coniferous forest soil and a seedling of silver birch (Betula pendula). A gradient of microarthropod diversit…
Hot spots, indicator taxa, complementarity and optimal networks of taiga
2000
If hot spots for different taxa coincide, priority-setting surveys in a region could be carried out more cheaply by focusing on indicator taxa. Several previous studies show that hot spots of different taxa rarely coincide. However, in tropical areas indicator taxa may be used in selecting complementary networks to represent biodiversity as a whole. We studied beetles (Coleoptera), Heteroptera, polypores or bracket fungi (Polyporaceae) and vascular plants of old growth boreal taiga forests. Optimal networks for Heteroptera maximized the high overall species richness of beetles and vascular plants, but these networks were least favourable options for polypores. Polypores are an important gro…