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Upscaling biodiversity: estimating the species–area relationship from small samples

Upscaling biodiversity: estimating the species–area relationship from small samples

Abstract. The challenge of biodiversity upscaling, estimating the species richness of a large area from scattered local surveys within it, has attracted increasing interest in recent years, pro- ducing a wide range of competing approaches. Such methods, if successful, could have important applications to multi-scale biodiversity estimation and monitoring. Here we test 19 techniques using a high quality plant data set: the GB Countryside Survey 1999, detailed surveys of a strati- fied random sample of British landscapes. In addition to the full data set, a set of geographical and statistical subsets was created, allowing each method to be tested on multiple data sets with different characteristics. The predictions of the models were tested against the “true” speciesarea relationship for British plants, derived from contemporaneously surveyed national atlas data. This represents a far more ambitious test than is usually employed, requiring 5 – 10 orders of magnitude in upscaling. The methods differed greatly in their performance; while there are 2,326 focal plant taxa recorded in the focal region, up-scaled species richness estimates ranged from 62 to 11,593. Several models provided reasonably reliable results across the 16 test data sets: the Shen and He and the Ulrich and Ollik models provided the most robust estimates of total species richness, with the former generally providing estimates within 10% of the true value. The methods tested proved less accurate at estimating the shape of the speciesarea relationship (SAR) as a whole; the best single method was Hui ’ s Occupancy Rank Curve approach, which erred on average by < 20%. A hybrid method combining a total species richness estimate (from the Shen and He model) with a downscaling approach (the Sizling model) proved more accurate in predicting the SAR (mean rel- ative error 15.5%) than any of the pure upscaling approaches tested. There remains substantial room for improvement in upscaling methods, but our results suggest that several existing methods have a high potential for practical application to estimating species richness at coarse spatial scales. The methods should greatly facilitate biodiversity estimation in poorly studied taxa and regions, and the monitoring of biodiversity change at multiple spatial scales.

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A field test of the relationship between habitat area and population size for five perennial plant species

A field test of the relationship between habitat area and population size for five perennial plant species

out of five investigated species seem to be able to respond to large habitat areas by forming large populations. Jacquemyn et al. (2002) found a significant relationship between forest area and population size for the forest herb Primula elatior. However, if the results of the present inves- tigation apply more generally, a fundamental assumption of incidence function models is not met with. This shed doubt on their general applicability (contrary to Hanski 1999) and on empirical studies of plant metapopulations (e.g. Quintana-Ascencio and Menges 1996). All five spe- cies are long-lived perennials with moderate reproductive output. Yet, they seem to differ in one or more vital at- tributes, which might be potential population growth rate. Alternatively, variation among the species in other at- tributes might explain results, e.g. dispersal ability and niche breadth. These will be discussed in turn.

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Phormium tenax, an unusual nurse plant

Phormium tenax, an unusual nurse plant

At Sugarloaf, Phormium tenax appears to be a successful nurse plant for native tree and shrub species facilitating succession to native forest. Seedlings and saplings of many woody plants were found in P. tenax clumps; in contrast no regeneration of woody species was observed in the grassland surrounding the clumps although occasional seedlings of woody plants were seen elsewhere in these grasslands. While the distance of individual P. tenax clumps from the remnant forest does not appear to influence regeneration within clumps, the size of the P. tenax clumps plays an important role (Table 2). As the area of each P. tenax clump increases so does the number of regenerating individuals present although there is no significant difference in species diversity with clump size. This relationship corresponds with a decrease in P. tenax cover, with the largest clumps generally being the most open. Those P. tenax clumps with high cover lack regeneration of woody species, while the most open clumps, which tend to be the largest, generally have an abundance of regeneration.

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The island–mainland species turnover relationship

The island–mainland species turnover relationship

composition could be determined from the IUCN range maps (figure 1; electronic supplementary material, figure S1). Each cookie-cutter’s orientation and placement was ran- domly determined. Owing to the larger land area in South America, purely random placement could result in under- representation of more northern environments. To account for this, we first selected a random latitude. Longitude was then randomly chosen from the available land at the chosen latitude. This approach is similar to the spreading-dye method of Algar & Losos [21] except that it preserved island shape as well as size. Each island in our study was represented by five MSRs, resulting in 230 non-overlapping MSRs for terraranans and 325 for anoles. Sampling was performed separately for anoles and terraranans and was lim- ited to regions with at least one anole (or terraranan) species. Following Algar & Losos [21], we excluded the disjunct distribution of Anolis carolinensis in the southeast US, as this region was colonized from the Caribbean [23], and whether it should be treated as part of the mainland or as a biogeographic island is unclear.

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Structure of the species-energy relationship

Structure of the species-energy relationship

relationship between energy availability, the overall amount of resources in an area, the total number of indi- viduals that can thus be maintained, and consequently the number of species. This predicts that individual species will probably be more abundant with increasing energy availability (figure 1c), that they will occupy more sites with increasing energy availability, and also that at lower energy levels there will be higher turnover in species ident- ities among sites than at higher ones (at which most spe- cies can maintain viable populations in most places). By contrast, what we shall call the ‘specialization’ hypothesis assumes that higher energy levels enable finer sub-division of available resources, either because of reductions in niche breadth or through the generation of greater resource diversity or habitat heterogeneity (e.g. Abrams 1995; Kerr et al. 2001). This predicts that individual spe- cies may become less abundant with increasing energy availability (figure 1d), that they will occupy fewer sites at higher energy availability, and also that there will tend to be higher turnover of species among sites at higher levels of energy availability than among sites at lower availability (see Whittaker 1960; Gaston & Williams 1996; Brown & Lomolino 1998).

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Dissecting the species–energy relationship

Dissecting the species–energy relationship

Kaspari et al. (2004) also found that the species richness of ant assemblages was more closely related to temperature than to plant productivity and suggested that such a pattern provided support for Rohde’s (1978, 1992) evolutionary rates hypothesis. This states that higher levels of solar radiation increase mutation rates, promoting faster molecular evolution and greater speciation, so more species occur in high-energy areas because more evolve there. The British avifauna contains one endemic bird species, Loxia scotica, although its taxonomic status is debated (Summers et al. 2002). We are not aware of any other suggestions that species of birds breeding in Britain evolved there. Indeed, this seems highly unlikely. First, Britain has been subject to frequent glaciation periods during which most species would have been displaced further south. Moreover, speciation in Britain could only have occurred during the interglacial periods and these were typically much shorter, approximately 25,000 years (Adams et al. 1999), than the time typically required for avian speciation, which has been estimated at between 250,000 and two million years (Avise et al. 1998; Johnson & Cicero 2004). Second, most species breeding in Britain have large geographic ranges covering Europe, and often parts of Asia and/or Africa (Gregory & Blackburn 1998); it would be rather remarkable if the majority of these species evolved in the same small area of their distribution. In addition, established exotic avian species in Britain exhibit a strong–species energy relationship (Evans et al. 2005d ), which cannot arise through a relationship between energy

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The Relationship between Birds Diversity and Habitats in Phou Khao Khouay (PKK) National Park of Lao PDR

The Relationship between Birds Diversity and Habitats in Phou Khao Khouay (PKK) National Park of Lao PDR

The structure and function of bird’s community can be further understood by analyzing and studying the feeding habits of birds. From the survey of bird’s feeding habits, the majority of the birds, a total of 83 species, accounting for 70.94% of the total bird species, were found to be carnivorous, which mainly feed on meat, aquatic animals and insects including a large numbers of water- fowl feeding on aquatic animals and insect-eating birds. The distribution range of this largest birds group is very wide, throughout all the surveying area in- cluding Tad Xai, the largest regional area. Because of having high habitat diver- sity with rich vegetation, Tad Xai provides favourable conditions for the growth of many insects like bees, butterflies, beetles, moths, flies, thus providing foods for insect-eating birds and consequently harbouring them. Moreover, large wa- ter bodies present in this area make it inhabitable for waterfowls as they supply adequate aquatic foods to them. The carnivorous groups were followed by a total of 32 species of graft mainly passeriformes fringillidae birds. However, compared to the first two groups, there were only 17 species of omnivorous birds. Feeding statis- tics of birds in the inspection area of PKK National Park is depicted in Figure 6.

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Evolution of diversity : analysis of species and speciation in Hemiandrus ground wētā : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Zoology, Massey University,  New Zealand

Evolution of diversity : analysis of species and speciation in Hemiandrus ground wētā : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Zoology, Massey University, New Zealand

Land area can have a positive influence on rates of endemism due its influence on speciation rates and extinction rates which tend to be higher and lower respectively in bigger areas (Crampton et al. 2010; Foote et al. 2007; Kisel and Barraclough 2010). Therefore I predicted that endemism would be highest in regions that have had more land available for a longer period of time. Some types of invertebrate species have been shown to have average durations of about nine million years (Foote et al. 2007), while mammal species have been suggested to have average durations of only one million years (Martin 1993). These timespans are compatible with genetic analyses that suggest geologically recent, rather than ancient processes are important for determining the distribution of a species (e.g. Trewick and Wallis (2001), McGlone et al. (2001)). I found that of all the environmental variables tested, only land area 3Ma was correlated significantly with endemism score, and no variables were correlated with species diversity or number of endemic species. Land area 3Ma was also one of the strongest correlates (β =0.018, p<0.0001) in the generalised linear model of number of endemic taxa. Current land area was not correlated with endemism and did not improve the GLM, suggesting that, land availability in the recent past has had a greater effect on endemism levels than currently available land. The most notable effector of the relationship between land area 3Ma and endemism is the lack of land in southern North Island which was still submerged until about 1.5 million years ago (Trewick and Bland 2011), and where there are currently few endemic species. In this scenario, historical biogeographical events are not masked by ecogeographical processes; recent geological history, rather than ecology, has made this a region of low endemism.

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Interactions between canopy structure and herbaceous biomass along environmental gradients in moist forest and dry miombo woodland of Tanzania

Interactions between canopy structure and herbaceous biomass along environmental gradients in moist forest and dry miombo woodland of Tanzania

Fig 2. Relationships between leaf area index (LAI), stand structural and environmental variables in moist forest and miombo woodland of Hanang district in Tanzania. (A) LAI shows a non-linear relationship with predominant height, (B) linear relationship with tree species richness, (C) soil nitrogen, (D) soil pH under high disturbance levels, (E) stem density and (F) tree species evenness when all other variables are set to their mean values (S2 Table, combined models). Solid lines plot fitted partial regressions from generalized linear models, with standard errors of the mean in dotted lines.

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Relationship between Psidium species (Myrtaceae) by resistance gene analog markers: focus on nematode resistance.

Relationship between Psidium species (Myrtaceae) by resistance gene analog markers: focus on nematode resistance.

The present study included the molecular characterization of Psidium species, some of which have little or no previous molecular description, providing important information for guava tree breeding programs. Furthermore, genetic variability of Psidium genotypes is evaluated using molecular markers, constituting the first description of RGA analysis in these species. The studied genotypes exhibit different genetic behavior, and can be useful for crossings, as rootstocks, or for the selection of genes of interest for guava breeding. The identification of differential genomic fragments in Psidium with resistance to M. enterolobii was accomplished, and common regions of RGAs were demonstrated in 10 Psidium species. This information has potential to be used for the development of markers of R genes for the breeding of P. guajava. Additionally, two DNA markers in genotypes that are susceptible and resistant to the nematode were compared. The differential RGAs identified are a valuable resource for the identification of R genes and the development of RGA molecular markers for the construction of genetic maps, and may also be useful for improving disease resistance. Hence, this work provides useful information for breeding programs of guava tree, especially with regard to resistance to M. enterolobii. This study also provides molecular evidence for studies of the plant-nematode interaction, an area in which there has been a delay compared to studies of other pathogens.

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Avian Species-Area Relationships and Environmental Covariates in Natural and Constructed Wetlands of Northeastern Alberta

Avian Species-Area Relationships and Environmental Covariates in Natural and Constructed Wetlands of Northeastern Alberta

Few studies have examined factors affecting avian species richness in constructed wetlands. Alsfeld et al. (2010) studied how richness in constructed wetlands in Delaware varied with respect to several variables of distance-to-neighbouring-habitat and found that forest area and proximity to forest were the strongest predictors of avian species richness. However, Alsfeld et al. (2010) did not consider variables of wetland size or wetland habitat characteristics. Hapner et al. (2011) found that species richness was only loosely tied to distance to the nearest forest within created and restored wetlands of Wisconsin. Within the constructed wetlands of the oilsands leased sites, Dagenais’ (2009) results corroborated those of Alsfeld et al. (2010), in that the overall species richness was greatest at wetlands closest to forest patches. In this study, the distance to the nearest forest was correlated weakly in the principal component analysis with percent open water and percent emergent vegetation cover. However, there was no significant relationship between species richness and percent open water cover in the constructed wetlands; so it would be difficult to comment on the relationship with proximity to forest. It is noteworthy that most wetlands were situated right at forest edge or within 50 m of a forest, still within the range of auditory detection of the point count. Therefore, some forest-resident bird species records were likely inadvertently included during the survey period and this may account for the lack of relationship.

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Plants Species Diversity along River Benue Bank under the Influence of Siltation and Solid Waste Effluents, Adamawa State, Nigeria

Plants Species Diversity along River Benue Bank under the Influence of Siltation and Solid Waste Effluents, Adamawa State, Nigeria

DOI: 10.4236/oalib.1104125 11 Open Access Library Journal productivity as a result of higher species diversity. In the present study amongst all the study sites, the increase in plant species diversity was observed more in NSW area (Table 5), which had not been polluted by either silt or waste efflu- ents. This corroborates the result of [20] who stated that amongst all the study stations (1 - 10) sited on the banks of the confluence of the Mula and Mutha Rivers, in Pune city at the south west of India stations 5 and 9 (Vitthalwadi Hol- kar Bridge) were represented as most diverse. It has highest species richness due to relatively less human intervention, whereas station 6 and 8 (Garware and Da- podi) were having the least species Shannon diversity index as a result of rea- sonably high population pressure, apparently patchy vegetation due to biotic in- ference involving farming practices, habitat destruction and domestic livestock.

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Ten year trend analysis of malaria prevalence in Kola Diba, North Gondar, Northwest Ethiopia

Ten year trend analysis of malaria prevalence in Kola Diba, North Gondar, Northwest Ethiopia

The study was conducted at Kola Diba health center (first health center in Ethiopia), Dembia District, which is located in north Gondar, Amhara region, 729 km north of Addis Ababa. Dembia is one of the districts of North Gondar Administrative Zone, known for its flat land. This district is malarious and covers an area of 1270 km with a total population of about 263000 and the population of the district is predominately Amhara, Orthodox Christianity being the main reli- gion. The altitude of the district ranges between 1750 and 2100 m above sea level. The District of Dembia lies close to Lake Tana (the largest lake in Ethiopia) and the majority of the population depends on subsist- ence farming. The administrative centre Kola Diba is only 35 km from the ancient city of Gondar. Malaria is the most prevalent seasonal disease in the area, accounted as second of all the reported diseases in the health center and October to December is the peak malaria transmission season in the area. Both P.vivax and P.falciparum exist in the area with P.falciparum prevailing all year.

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Floristic Analysis of the Species concerning the Astragalus L. Type Spread in the Daridagh Area

Floristic Analysis of the Species concerning the Astragalus L. Type Spread in the Daridagh Area

of Armenia, Iran and Central Asia. The Iranian group extends to Tien Shan and western Pamir, covering a large area. This group covers all Iranian territory, especially mountainous and Caspian shore areas. This group is originally a group of Northern Iran (Atropathan) that incorporated mountain xerophytic plants in the area, including A.cancellatus Bunge, A.kochichus Sosn, A.schelkovinikovii Grossh, A.asterias Stev.ex Ledeb, A.argyroides G. Beck ex Stapf. A.fabaceus Bieb species.

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Vegetation Composition And Diversity In Oil And Gas Facility, Grissik Village, South Sumatra

Vegetation Composition And Diversity In Oil And Gas Facility, Grissik Village, South Sumatra

Mining activity is a promising business sector in terms of economy. Many countries have made mining industry as one of the main sectors for GDP contribution, as well as Indonesia. Since 1997 Asian monetary crisis that also caused major conflict in Indonesia’s economy and business sector, the mining sector has become a dependable and important supplier to Indonesia’s domestic income [1]. According to PwC (2016) [2], Indonesia is also one of important member in international mining industry with significant production of copper, gold, coal, nickel, and tin. Indonesia also become world's largest exporters of thermal coal. Global mining companies consistently rank Indonesian highly in terms of coal and mineral prospects [3]. However, usually, this business sector cannot be in line with environmental sustainability. Mining activity is often linked to activities that can damage the environment. Some types of mining operations may have environmental impacts, such as land clearing, waterways diversion, river bank breakdown, moreover, logging of couple of plants in excavation work [4]. In fact, biodiversity is essential thing for mining industries to show their dependencies and impacts on biodiversity and ecosystem services [5]. According to Morton et al (2014) [6], negative influences on biodiversity can accumulate when there are numerous mining activities within a region and regional development around mines can reach these negative effects across a wider area. Morton et al (2014) [6] more over stated that There are three main strategies to moderate the impact of mining on biodiversity: before mining begins, during the life of a mine, and when mines close. Mining is not industry with green prospects. Because of that, challenges are greater for some sectors of the mining industry than for others. Using land in greater sympathy with wildlife is such intrinsic practices to a more caring corporate culture and likely to promote attention and loyalty among some customers. Furthermore, these measures contribute to improving overall environmental performance and

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Minimum area of forests left to spontaneous development in protected areas

Minimum area of forests left to spontaneous development in protected areas

val forest reserve the area on which the respective commu- nity of natural forest can be taken as a biologically (in terms of growth and development) autonomous, permanently dy- namically balanced unit of autochthonous primeval forest. The area proportion of basic developmental stages, aver- age growing stock and current increment are approximately identical with this area for a long time. A permanent nutrient cycle is guaranteed there while the essence and the form of primeval forest are roughly identical. In the course of 40-years’ research on primeval forests in Slovakia Korpeľ drew a conclusion that more than 30 ha are a sufficiently large area for developmental autonomy and guaranteed per- sistence in natural environmental conditions. He considered the area above 50 ha as optimum for the development and persistence of primeval forest (K ORPEĽ 1989). Similar

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To Investigate the Effect of Electromagnetic Radiations on Flavonoids of Lettuce Species

To Investigate the Effect of Electromagnetic Radiations on Flavonoids of Lettuce Species

The readily increase in the rate of cell phones, diverted all the researchers to detect the effect of radio waves on living organisms not only on humans but also on plants. Many studies suggested adverse health symptoms which are caused by mobile phone radiations. Exposure to these mobile phone radiations can cause ill effects; cell damage by formation of reactive oxygen species and ultimately cell death. These radiations are of two types and that are- ionizing and non- ionizing radiations and both of them affect the environment, human and plants. These radiations

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Nanoscale Thermal and Electronic Properties of Thin Films of Graphene and Organic Polyradicals

Nanoscale Thermal and Electronic Properties of Thin Films of Graphene and Organic Polyradicals

the electrical conductivity of the nanocomposites is nearly the same. This condition is described in panel (c) of Figure 6.8, where it can be seen that P6OV aggregates limitedly connect the graphene-based platelets. Going further, panel (d) demonstrates that at higher coverage area (quite above graphene percolation threshold) for which there is sufficient pathway for charge transport, the polymer imbeds the platelets and acting more as an insulating layer. In this morphology regime, all the graphene platelets tend to interlace with each other and only a thin P6OV layer of a few nm separates them. Transport between graphene platelets is therefore facilitated by the quantum mechanical tunneling and hopping between localized states situated at specific charged monomers along the polymer filament [14]. Since charge hopping is less efficient than free carrier transport, the electrical transport in the nanocomposites also becomes less efficient. This is responsible for the decrease in conductivity in the sample with the lowest (1-f) voids shown in Figure 6.8(a).

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The Invasive Species of Walhalla Area in Columbus, Ohio

The Invasive Species of Walhalla Area in Columbus, Ohio

Invasive species are plants, animals, or pathogens that are non-native (or alien) to the ecosystem under consideration and whose introduction causes or is likely to cause harm. Invasive species can harm both the natural resources in an ecosystem as well as threaten human use of these resources. Walhalla is an urban wooded ravine area (10 acre area) in the middle of Columbus, Ohio. Many residents are actually actively planting new invasive species in a misguided attempt to prevent erosion on their property. Other properties are suffering from not-so-benign neglect, as the existing trees are slowly succumbing to insect infestation and rot (because of moisture trapped by ivy, etc.) and no new saplings are emerging to replace them (because of the thick ground cover). In both of these instances, it’s proving to be difficult to con- vince the landowners that they’re causing more harm than good—the local soil & water conservation people are all too eager to reinforce the notion that the ground must be covered with a blanket of impenetrable invasive species in order to prevent erosion. The objectives of this study were to collect and identify the invasive species in Walhalla area in order to educate the residents about these species and its impact on their properties and gardens; moreover, using the findings of this project to de- velop a plan to remove these dangerous species. This survey has documented 18 in- vasive species in 18 families. Two notable invasive species were found in this area, Alliaria petiolata (M. Bieb.) Cavara & Grande and Hedera helix L. (English Ivy). The found invasive species have an abundant growth in the studied area. The studied area has had no previous botanical collecting. Therefore, the area was in an urgent need to be inventoried and analyzed in order to identify and document its invasive species. Moreover, these identified species will be used for educational purposes for the resi- dents of this area and well rounded plan is developed to remove these harmful spe- cies. This inventory represents a model for the other residential and agricultural areas in the state to follow, which will help overcome the negative impact and dam- age caused by the invasive species in these areas.

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Phylogenetic relationship of six species of Pyrgomorphidae (Orthoptera: Caelifera: Acridomorpha) as revealed by RAPD PCR analysis

Phylogenetic relationship of six species of Pyrgomorphidae (Orthoptera: Caelifera: Acridomorpha) as revealed by RAPD PCR analysis

OPAA-09 did not generate bands in sample A.c.crenulata, C.oxypterus, P.picta OPAI-05&OPB-10 did not produce bands in sample P.pictus,OPB-18 did not produce bands in P.picta, C.oxypterus and C.tracypterus OPAI-05 andOPB-10 produced no bands for P.pictaOPC-06 produced more number of bands with 41 of total bands, from all the 10 different primers. Similarly other primers generated bands ranging between 19-32.Polymorphism for bands profile is presented in Table-2. The result was subjected to cluster analysis which shows 2 main cluster A&B. Cluster A includes 2 species Neorthacrisacuticepsacuticeps&Atractomorphacrenulatacrenu lata,with respect to distance values and cluster B has four species dividing further into 3 branches. Of these Poecilocerapicta & Pyrgomorphabispinosabispinosa are closely related and Chrotogonusoxypterus & Chrotogonustrachypterus are distantly related to each other. Even the unrooted tree profile shows Poecilocerapicta &

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