Factors affecting species richness pdf

Investigations of species richness effects on ecosystem. Biophysical factors, land use, and species viability in. Factors affecting species diversitycorona species diversity 11. Although some of these issues have been resolved it is still not obvious how to perform studies on species loss so that they may be relevant to effects of species. Flather and carolyn hull sieg in virtually all ecological communities around the world, most species are represented by few individuals, and most individuals come from only a few of the most common species. This function provides tools for the identification of most likely causal factors significantly correlated with species richness by following these steps. The response of the species richness of this guild to ecological processes is evaluated in this paper. Global distributional gradientsinterregional differences mangrove plants are found throughout the world in tropical regions and occasionally in. Jahanbakhsh ganjeh et al factors influencing abundance and species richness of overwintered waterbirds in parishan international. Understanding the factors that affect and are affected by smallscale species richness is fundamental to understanding how eco logical.

Factors determining mammal species richness on habitat islands and isolates. Description usage arguments details value authors references examples. Factors affecting the species richness, composition and horizontal. Considering all the species, the models of abundance highlighted the negative influence of altitude, proportion of land covered by forests and grasslands, and the positive influence of slope, proportion of land covered by shrubs and habitat diversity. Temporal variation of ecological factors affecting bird species richness in urban and periurban forests in a changing environment. June 2011 species richness and ecological limits 77.

The effect of management related factors on species richness of epiphytic bryophytes and lichens was studied in managed deciduousconiferous mixed forests in westernhungary. Factors influencing epiphytic bryophyte and lichen species. With regard to species richness s, a total of 20 ant species were detected in undisturbed orchard plots table 1, figure 2. The pattern in anuran species richness along the elevational gradient was investigated using. Fox school of biological science, university of new south wales, sydney 2052, australia, e. Species richness is typically greater on larger islands and more species are found on islands that are nearer to the mainland the source of colonization. Species richness s, and both shannonwiener and simpsons diversity indices were best explained by independent pca factors involving leaf litter, water volume, dissolved oxygen concentrations, and tank light levels. Factors affecting songbird richness, abundance, and nest. However, abundances of certain species were higher in patches adjacent to small order streams indicating that these areas may be important to. The causes of species richness patterns across space. Species abundance is the number of individuals per species, and relative abundance refers to the evenness of distribution of. Factors affecting stem borer parasitoid species diversity. Allopatric speciation that occurs when biological populations of the same species become isolated from each other to an extent that prevents or interferes with genetic interchange. In this chapter we continue by examining the relationships between species richness and factors that can be thought of as exerting an influence in their own right.

The causes of species richness patterns across space, time, and clades and the role of. Environmental factors affecting the composition and. In 2009, the staphylind fauna was studied in six habitats of the baltic sea coast of schleswigholstein northern germany. Factors affecting the distribution pattern of wild plants. Biological factors that affect species richness competition competitive exclusion, perhaps the most often cited form of species interaction in ecology, occurs when one species species richness. Effects of habitat and human activities on species. We used the software package modestr to determine the geographical distribution of all valid marine elasmobranch species 512 species of sharks and 619 species of batoids. Effect of habitat complexity attributes on species richness jasmine i.

Pdf factors that affect the species richness of the. Factors determining mammal species richness on habitat. Factors and processes affecting plant biodiversity in permanent. Factors affecting fish species richness in ontario lakes. Factors affecting plant species richness and endemism in the south aegean 287 riables with a tolerance value larger than 0. Permanent grasslands are kind of agricultural fields with high biodiversity in farmlands due to high plant species diversity gibon 2005. Factors affecting avian species richness and density in. Fish species richness in relation to lake area, ph, and other abiotic factors in ontario lakes. Ecological and historical factors affecting distribution pattern and richness of endemic plant species. How does species richness of tree regeneration respond to small. Experimental factors affecting pcrbased estimates of. The afroalpine moorlands of the bale mountains national park bmnp constitute a diverse guild of avian carnivores. Pdf the loess plateau of china is a special region that has suffered from soil erosion and water loss for a long time.

Species diversity is determined not only by the number of species within a biological communityi. The effect of urbanization on ant abundance and diversity. Many factors affect smallscale species richness, including geographic e. Construction activities resulted in the permanent loss of 17 species 85% decline and only 3 species were present right after construction was completed and 4 species were present 1 year after construction was completed. Factors influencing abundance and species applied ecology and. Bird species richness and community composition metrics provide a means to assess effects of management or conservation efforts. Factors affecting frog species richness in the solomon. Factors affecting species richness our results showed that the species richness of extremely small populations was always reduced by human activities figure 3a, 3b. Species richness and diversity did not differ with relative tank age, however abundances of a midge and a mosquito species did. Factors affecting plant species richness and endemism on. Pdf factors affecting plant species richness in field. Factors influencing biodiversity and distributional. Factors affecting macroinvertebrate richness and diversity. Temporal variation of ecological factors affecting bird.

Pdf field boundaries are expected to support the maintenance of biodiversity in agroecosystems, since they provide the habitat for a range of plant. I found that species richness was positively associated with patch width but was not related to stream size. The key to the survival of ecosystems is the ability to adapt. Environmental and spatial factors affecting species richness and composition in urban ponds chloe jaquenoud, ruddy montan, eduardo mora, faith perez, yvonne scorcia, carol henger, sarah davis figure 1. Factors affecting macroinvertebrate richness and diversity in portuguese streams. Effect of habitat complexity attributes on species richness. During the rapid economic growth of japan over recent decades, some igune woodlots have been abandoned or logged. Igune, a traditional agricultural landscape in the tohoku region of japan, is characterized by smallscale artificial woodlots surrounding a farmers house that are interspersed with paddy fields. Factors affecting species diversity of plant communities. Factors affecting species richness and distribution. Understanding the factors that affect and are affected by small scale species richness is fundamental to community ecology. Two key factors in equatorialpolar gradients of species richness are probably evolutionary history and climate.

Many factors apply at more than one scale, but in each case it is useful to draw out the subtle distinctions. The effect of forest maturity and fragmentation was also a possible factor affecting species richness and evenness 31. To estimate these metrics, we used methods that incorporated species detection probabilities from data collected at 160 points at 23 sites on the san pedro river during 19982001. A number of these factors have been discussed in previous chapters disturbance and successional status in chapter 16, competition, predation and parasitism in chapter 19. Four types of factor affecting species richness species. The following habitats lagoon, sandy beach, shingle beach, primary dune, wooded cliff, and woodless cliff were significantly separated by their species composition. Factors affecting species richness of marine elasmobranchs. Species richness and diversity significantly increased with increased time since abandonment. Ponds that are disconnected or connected by underground channels have different species compositions while those that are. A multiple regression model of species richness accounted for 48% of variance. Identification of the factors affecting species richness.

We used the software package modestr to determine the geographical distribution of all valid marine elasmobranch species 512 species. We compared species richness and densities of breeding songbirds among 3 narrow 5595 m and 3 wide 400530 m forested. They form a landbridge, connecting the coasts of the southeastern continental part of greece peloponnisos with southern asia minor and forming the anna kagiampaki et al. Biology help describe factors that affect species richness. Ecological and historical factors affecting distribution. These results are in agreement with several previous studies luisa et al. At the stand level, the potential explanatory variables were tree species composition, stand structure, microclimate and light conditions, landscape and historical variables. Factors affecting avian species richness and occupancy in a tropical city in southern china. Species abundance is the number of individuals per species, and relative abundance refers to the evenness of. There is a strong inverse correlation in many groups between species richness and latitude. Exploring trends in species richness and the distribution of individual species over time as well as the factors affecting these trends informs conservation. Kovalenko 1,2 1department of biological sciences, university of windsor, windsor, ontario n9b3p4 canada 2natural resources research institute, university of minnesota, duluth, minnesota 55811 usa citation. You make the assumption that each organism constitutes a single species.

The south aegean islands are mainly of continental origin. Species richness generally declines along an equatorialpolar gradient and is especially great in the tropics. Abstract riparian areas are an important part of conservation efforts directed toward minimizing the effects of habitat loss on birds because riparian areas host a large number of bird species. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Islands constitute welldefined fragmented areas enabling reliable plant inventories and, often, hosting many endemic taxa. Species richness, very simply, is a count of the different species in a given ecosystem, region or particular area. Environmental factors affecting endemic species, species richness and species diversity in saint catherine protectorate, south sinai, egypt. This study indicated that bamboo forests and windbreak forests had a positive. If an ecosystem can maintain balance, it will survive. Speciation is the evolutionary process by which new biological species arise. Factors affecting plant species richness and endemism in the south aegean283. The models excluding the egyptian vulture selected.

Different habitat types affect bird richness and evenness. Urban and periurban forests determine different habitat services for biodiversity according to their characteristics. An increase in two local abiotic factors, lake area and mean depth, increased richness. Factors influencing species richness and community. Pdf factors affecting species diversity of plant communities and.

Importance of human disturbance and open green space myungbok lee, indika peabotuwage, hao gu. If this is the first time you use this feature, you will be asked to authorise cambridge core to connect with your account. The change in species richness and diversity is the main indicator of the succession process lin et al. Factors affecting plant species richness in field boundaries in the mediterranean region article pdf available in biodiversity and conservation 214. While humans have had the greatest impact, other natural factors such as weather and fire have influenced ecosystems. Factors affecting their species richness such as area, isolation, altitude and habitat diversity are relatively easy to measure. Of the two regional factors included in the model, watershed species richness increased lake species richness and elevation decreased it. Vegetation and soil moisture were the most important factors separating the assemblages. Pdf environmental factors affecting endemic species. Many studies on elasmobranchs, sharks and batoids rays, skates and guitarfishes, have focused on the factors responsible for biomass decline, but little attention has been paid to the factors that affect species richness. Factors affecting plant species richness and endemism in. Effects of environmental factors on the species richness.