Biodiversity Hotspot

The Western Ghats of India and Sri Lanka biodiversity hotspot is often regarded as one unit because of shared biogeographical history. However, recent studies suggest that certain faunal components, particularly in the wet zones are distinct. This article looks at the existing information on species richness and endemicity of taxa in both regions. Data are available on some taxa but not on others, and many taxa have not received equal attention in both regions. The natural ecosystems of this hotspot are under threat and urgent conservation action is needed, especially in augmenting the protected area network. There is also the need for increasing the level of scientific collaboration in biodiversity studies between the two countries.

Biodiversity, a central component of Earth's life support systems, is directly relevant to human societies. We examine the dimensions and nature of the Earth's terrestrial biodiversity and review the scientific facts concerning the rate of loss of biodiversity and the drivers of this loss. The estimate for the total number of species of eukaryotic organisms possible lies in the 5-15

Heterogeneous landscapes are biodiversity ‘hotspots’. Degradation resulting from acidification, desiccation and eutrophication not only decreases habitat quality, but also causes heterogeneity to decline. While restoration measures aim at restoring habitat quality, they can further reduce heterogeneity when they affect large parts of an area (large scale) or cause disturbance (high intensity). Successful restoration of biological diversity therefore requires knowledge of the mechanisms underlying the relation between landscape heterogeneity and species diversity. This paper addresses two questions: (1) Do bog pools in a heterogeneous landscape harbour more aquatic macroinvertebrate species than those located in more homogeneous landscapes? (2) Is distance between water bodies an important factor determining species composition? To answer the first question, aquatic macroinvertebrate assemblages in bog pools with a similar water chemistry range were studied in bog remnants differing ...

Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species’ threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project – and avert – future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse ...

ABSTRACT The Japanese archipelago is a biodiversity hotspot with a unique regional climate influenced by the Asian monsoon circulation, surrounding seas, and complex topography. Japan has numerous mountains and islands, which are potentially vulnerable to climate change. This study evaluated the potential impact of climate change on species diversity in Japan, using 25 conifer tree species as a case study. We applied ensemble models based on generalised additive models, artificial neural networks, generalised boosted-models, and random forests to species' locality records at 1 km(2) resolution. The results indicated a substantial impact, such that 80% of the species may lose over half of their current climatically suitable areas by 2100. The lower attitudinal range limits were projected to shift upwards by 293 m on average, suggesting that alpine/sub-alpine and sub-boreal species may face widespread local extinctions. The impacts on sub-alpine species may be moderated by assisted migration to the northern island where they currently do not occur. However, climatically suitable areas for these species and sub-boreal species that occur on the island overlapped significantly, indicating that assisted migration may entail the risk of introducing biotic competition or interbreeding. Thus, rugged topography and dispersal barriers between islands are likely to amplify the future impacts of climate change in Japan. Limited areas in the central mountain region were identified as potential bioclimatic refugia, which should be conserved as a priority. (C) 2010 Elsevier Ltd. All rights reserved.

ABSTRACT The Japanese archipelago is a biodiversity hotspot with a unique regional climate influenced by the Asian monsoon circulation, surrounding seas, and complex topography. Japan has numerous mountains and islands, which are potentially vulnerable to climate change. This study evaluated the potential impact of climate change on species diversity in Japan, using 25 conifer tree species as a case study. We applied ensemble models based on generalised additive models, artificial neural networks, generalised boosted-models, and random forests to species' locality records at 1 km(2) resolution. The results indicated a substantial impact, such that 80% of the species may lose over half of their current climatically suitable areas by 2100. The lower attitudinal range limits were projected to shift upwards by 293 m on average, suggesting that alpine/sub-alpine and sub-boreal species may face widespread local extinctions. The impacts on sub-alpine species may be moderated by assisted migration to the northern island where they currently do not occur. However, climatically suitable areas for these species and sub-boreal species that occur on the island overlapped significantly, indicating that assisted migration may entail the risk of introducing biotic competition or interbreeding. Thus, rugged topography and dispersal barriers between islands are likely to amplify the future impacts of climate change in Japan. Limited areas in the central mountain region were identified as potential bioclimatic refugia, which should be conserved as a priority. (C) 2010 Elsevier Ltd. All rights reserved.

Ecological restoration (ER) can be defined as “the process of assisting the recovery of an ecosystem that has been degraded, damaged or destroyed” (SER 2004). To this bare-bones definition, we would add that ER is a process that recovers and improves the functionality of ...

... C. Dean a b * & G. Wardell‐Johnson a pages 180-193. ... Coops, NC. 2002. Eucalypt forest structure and synthetic aperture radar backscatter: A theoretical analysis. Trends Ecol Evol , 16: 28–46. View all references; Dean & Roxburgh 200618. Dean, C and Roxburgh, SH. 2006. ...

We assessed collection intensity of forest products in three regions of the Western Ghats: Kogar, Sigur and KMTR with differing population densities and levels of forest protection. Fuel-wood was intensively collected in all three regions; fodder and green leaves in pre-dominantly agricultural regions and cattle manure in Sigur. Agriculture, wage labour and local and regional markets were associated with resource harvesting. Collection intensity decreased with increasing levels of protection, regardless of human density. Extensive for-est degradation in these regions suggests that the in-tensive use of forests for sustenance and consumption is no longer viable.

Central Chile is an important biodiversity hotspot in Latin America. Biodiversity hotspots are characterised by a high number of endemic species cooccurring with a high level of anthropogenic pressure. In central Chile, the pressure is caused by land-use change, in which near-natural primary and secondary forests are replaced and fragmented by commercial pine and eucalyptus plantations. Large forest fires are another factor that can potentially endanger biodiversity. Usually, environmental hazards, such as wildfires, are part of the regular environmental dynamic and not considered a threat to biodiversity. Nonetheless, this situation may change if land-use change and altered wildfire regimes coerce. Land-use change pressure may destroy landscape integrity in terms of habitat loss and fragmentation, while wildfires may destroy the last remnants of native forests. This study aims to understand the joint effects of land-use change and a catastrophic wildfire on habitat loss and habitat...

Background Although allopatric speciation is viewed as the most common way in which species originate, allopatric divergence among a group of closely related species has rarely been examined at the population level through phylogeographic analysis. Here we report such a case study on eight putative cypress (Cupressus) species, which each have a mainly allopatric distribution in the Qinghai-Tibetan Plateau (QTP) and adjacent regions. The analysis involved sequencing three plastid DNA fragments (trnD-trnT, trnS-trnG and trnL-trnF) in 371 individuals sampled from populations at 66 localities. Results Both phylogenetic and network analyses showed that most DNA haplotypes recovered or haplotype-clustered lineages resolved were largely species-specific. Across all species, significant phylogeographic structure (N ST > G ST, P < 0.05) implied a high correlation between haplotypes/lineages and geographic distribution. Two species, C. duclouxiana and C. chengiana, which are distributed...

Abstract: Habitat loss is silently leading numerous insects to extinction. Conservation efforts, however, have not been designed specifically to protect these organisms, despite their ecological and evolutionary significance. On the basis of species–host area equations, ...

Habitat degradation has over time formed synergy with other factors to contribute to dwindling populations of both fauna and flora by altering their habitats. The disturbance of natural habitats affects the diversity of both vertebrates and invertebrates by altering both feeding and nesting sites for which organisms are known to depend on for survival. Little is known of the extent to which vulnerable habitats could shape the diversity of most indigent pollinators such as African meliponine bee species in tropical ecosystems. This study was conducted to determine how disturbance could shape the natural occurrence of African meliponine bee species in different ecological habitats of Taita Hills, leading to changes in their diversity. A total of four species depicted by the Renyi diversity profile was recorded in five of the six main habitat types surveyed, and a further extrapolation with Shannon index ( EH) also predicted the highest species richness of 4.24 in a deciduous habitat t...

Bushmeat hunting constitutes the most immediate threat to wildlife populations in the Udzungwa Mountains of the Eastern Afromontane biodiversity hotspot. This study assesses the impact of hunting by comparing densities of mammalian species between the little hunted West Kilombero Scarp Forest Reserve (WKSFR), the medium-hunted Udzungwa Scarp Forest Reserve (USFR) and the intensively hunted New Dabaga Ulangambi Forest Reserve (NDUFR). Of the 22 species recorded, 20 were present in WKSFR, 17 in USFR and 12 in NDUFR. Most large species (>40 kg.) were absent from hunted areas, while medium-sized species were reduced more than smaller species. Few traces of Abbot’s duiker were observed in hunted areas and bush pig was reduced below 85% in hunted areas. Hunting appears to have little effect on primates, blue duiker, Harvey’s duiker, aardvark, eastern tree hyrax, and giant pouched rat in USFR, while hunting in NDUFR only seems of less concern for primates and giant pouched rat. Thus, th...