Conservation priorities in the Southern Central Andes: mismatch between endemism and diversity hotspots in the regional flora

North western Argentina, the southernmost portion of the tropical Andes, contains one of the main areas of endemism within the Southern Cone, as well as one of the main diversity hotspots of the country. Historically its reserve area systems have been located in the richest ecoregion of the area; the Southern Andean Yungas. We evaluated the effectiveness of the current protected areas in preserving the endemic flora of the region. The distributions of 505 endemic species were either modeled or included as observed data to determine endemism hotspots in each ecoregion. The endemic species were mainly found in arid ecoregions such as the High Monte and the Central Andean Puna, as well as in the transition zones between these regions and the Southern Andean Yungas. We found that more than 1/3 of the endemic species are unprotected in their entire ranges by the current system, while nearly half of the species are protected in only 5 % of their distribution ranges. New priority areas were chosen to increase the effectiveness based on the irreplaceability concept. We show that adding 251 new cells of 100 km² each would improve the protection values and convert the system to effective. The present paper highlights that priorities set on the basis of species richness may not successfully conserve areas of high plant endemism. However, zoologist would have to realize similar assessments in the endemic fauna in order to find the optimal designed of protected areas system to conserve both the endemic flora and fauna in the Southern Central Andes.     

Fish fauna of Chalakudy River,part of Western Ghats biodiversity hotspot,Kerala, India: patterns of distribution,threats and conservation needs

Seventy one fish species belonging to 27 families and 50 genera were collected from various sampling sites spread along the upstream and downstream parts of the Chalakudy river, in the Western Ghats biodiversity hotspot in Kerala, South India. Cyprinids were the most dominant group represented by 24 species belonging to 13 genera, followed by the catfishes of the family Bagridae (7 species from 2 genera) and loaches belonging to the family Balitoridae (5 species from 5 genera). Of the 71 species, 4 belong to the ‘critically endangered’ (CR) and 16 to the ‘endangered’ (EN) category. 3 of the critically endangered species are strictly endemic to the Chalakudy river system. We also collected 5 exotic species several of them categorized as potential pest. Fish species richness (FSR) showed a direct relationship with increasing stream order with maximum values observed in the downstream/low elevation regions. Considerable differences were observed in the FSR between different microhabitats with maximum values observed in bed rock and pool riffle and the lowest in regimes followed by step pools. Diversity and species richness decreased with increasing altitude and higher diversity and species richness were observed in sampling sites located between 0–200 m above sea level. A definite temporal partitioning was also observed with regard to FSR with higher richness during the day time and the lowest observed at dawn. Indiscriminate collection of endemic and threatened ornamental fish species for export, exploitation of endangered food fishes by forest-dwelling communities and local fisher folk, pollution, loss of riparian cover, damming and exotic species threaten the rich ichthyofaunal diversity of Chalakudy River. An urgent need exists for studying the life history traits and demography of the most important endemic and threatened fishes, as lack of information on these aspects have significantly affected conservation efforts. The implementation of strong management strategies like fixing total allowable catch (TAC), and the use of quotas are needed to reduce the overall collection pressure with regard to the trade in native ornamental species from the river.     

Are protected areas maintaining bird diversity?

Evaluating the effectiveness of protected areas for sustaining biodiversity is crucial to achieving conservation outcomes. While studies of effectiveness have improved our understanding of protected‐area design and management, few investigations (< 5%) have quantified the ecological performance of reserves for conserving species. Here, we present an empirical evaluation of protected‐area effectiveness using long‐term measures of a vulnerable assemblage of species. We compare forest and woodland bird diversity in the Australian Capital Territory over 11 yr on protected and unprotected areas located in temperate eucalypt woodland and matched by key habitat attributes. We examine separately the response of birds to protected areas established prior to 1995 and after 1995 when fundamental changes were made to regional conservation policy. Bird diversity was measured in richness, occurrence of vulnerable species, individual species trajectories and functional trait groups. We found that protected areas were effective in maintaining woody vegetation cover in the study region, but were less effective in the protection of the target bird species assemblage. Protected areas were less species rich than unprotected areas, with significant declines in richness across sites protected prior to 1995. Small, specialised and vulnerable species showed stronger associations with unprotected areas than protected areas. Our findings indicate that recently established reserves (post‐1995) are performing similarly to unprotected woodland areas in terms of maintaining woodland bird diversity, and that both of these areas are more effective in the conservation of woodland bird populations than reserves established prior to 1995. We demonstrate that the conservation value of protected areas is strongly influenced by the physical characteristics, as well as the landscape context, of a given reserve and can diminish with changes in surrounding land use over time. Both protected areas and off‐reserve conservation schemes have important roles to play in securing species populations.     

沙区植物多样性保护研究进展

沙区景观表现为沙丘和低地交错分布.沙区常具独特的植物区系,含有特有和稀有植物.沙区植物丰富度降低和特有(稀有)植物消失问题近些年已受到很大关注,被列入国际生物多样性保护计划,很多国家和地区都对此开展了专门的研究.本文以近期发表的文献为基础,从植物多样性保护问题的提出、植物多样性形成机制、植物多样性保护途径、植物多样性研究与生态学理论的发展等方面论述了沙区植物多样性保护及其研究进展.沙区植物多样性保护应注意植物多样性保护目标的地域间差异(维持沙丘上的高植物丰富度还是保护特有或稀有植物)、流沙固定-植物多样性保护间的均衡、"植物多样性保护的量(高的植物丰富度)-质(特有或稀有植物出现)"间的均衡.还应将沙丘体和丘间低地视为一个统一体,研究干扰和生境破碎化对植物多样性造成的影响.     

Plant diversity and priority conservation areas of Northwestern Yunnan,China

The Global Plant Conservation Strategy of the Convention on Biological Diversity calls for “protection of 50% of the most important areas for plant diversity.” All global biodiversity analyses have identified the mountains of northwestern Yunnan as a conservation priority for plant diversity. The challenge we were presented with was how to transform this sweeping global recognition into regional geographic priorities and measurable conservation action. This challenge is especially acute in Yunnan where there are no readily accessible data on the distribution and status of plant diversity, yet great conservation urgency due to the rapid pace of economic development. We used endangered and endemic species to represent plant diversity as a whole due to time and financial constraints. To identify conservation priorities, we relied on experts’ knowledge, supplemented with a rapidly assembled plant diversity data base, rapid field assessments to fill knowledge gaps, and analyses of the spatial patterns of richness and habitat relationships. Ninety-eight endangered species and 703 endemic species occur in the project area. Experts identified nine Plant Diversity Conservation Areas for northwestern Yunnan, including eight specific geographies and one priority habitat. We found that the current nature reserve system is serving an important role in plant diversity protection, even though many of the reserves were not specifically designated for plant diversity considerations. This project provided a means for scientific experts to directly contribute to conservation decision-making by government and Non-Government Organizations, and essential information for the plant conservation in Northwestern Yunnan.     

Scale dependence of plant species richness in a network of protected areas

Despite the widely recognised importance of reserve networks, their effectiveness in encompassing and maintaining biodiversity is still debated. Species diversity is one of the most affordable measures of biodiversity, but it is difficult to survey such data over large scales. This research aimed to perform a sample-based assessment of species richness of groups of plants with different conservation value (alien species, protected species, and all species) within a reserve network, testing the use of partitioning as a tool for assessing diversity at different spatial scales, from the plot to the entire network. Plant diversity patterns differed for the groups of species for most of the investigated spatial scales. Despite these patterns assumed divergent tendencies when different species groups were considered, most of the species richness within the network was given by larger scale β-diversity for both alien and protected species, as well for all species. Diversity partitioning proved an effective tool to quantify the role of spatial scales in structuring the total species richness of the network, and is helpful in planning reserve networks.     

Optimizing conservation of forest diversity: a country-wide approach in Mexico

A recent vegetation study [Palacio-Prieto et al. (2000) Bol Inst Geogr UNAM 43:183–203] showed that Mexico’s forest area has declined to 33.3%, from originally 52.0% of the country’s land area. In order to assess strategies for tree diversity conservation, we compiled a list of 846 tree species native to Mexico, and determined for each the presence or absence in 234 geographical squares of 1° latitude by 1° longitude (approximately 106 × 106 km). On the average, any two squares shared only 6% of their species composition. Using a standard optimization method from engineering and economics [Dantzig (1963) Linear programming and extensions. Princeton University Press, Princeton, NJ, USA, 625 p], we determined the minimally necessary land area in Mexico to conserve the 846 tree species, while securing that each species is found in an area of (approximately) 1,100 km² of currently existing forest vegetation. Furthermore, we took into account 15 existing protected areas with a size of at least 1,100 km² each. With these constraints, the total minimum area needed to conserve all 846 tree species is 45,136 km² of currently existing forest vegetation, or 2.3% of Mexico’s surface. While this analysis can be refined with subsequent field work, the proposed reserve network indicates that efficient land use planning on a national scale may be able to conserve tree species diversity in a relatively small portion of Mexico, even after severe deforestation has taken place.     

Characterizing ecological generalization in plant-pollination systems

Despite the development of diversity indices in community ecology that incorporate both richness and evenness, pollination biologists commonly use only pollinator richness to estimate generalization. Similarly, while pollination biologists have stressed the utility of pollinator importance, incorporating both pollinator abundance and effectiveness, importance values have not been included in estimates of generalization in pollination systems. In this study, we estimated pollinator generalization for 17 plant species using Simpson’s diversity index, which includes richness and evenness. We compared these estimates with estimates based on only pollinator richness, and compared diversity estimates calculated using importance data with those using only visitation data. We found that pollinator richness explains only 57–65% of the variation in diversity, and that, for most plant species, pollinator importance was determined primarily by differences in visitation rather than by differences in effectiveness. While simple richness may suffice for broad comparisons of pollinator generalization, measures that incorporate evenness will provide a much more accurate understanding of generalization. Although incorporating labor-intensive measurements of pollinator effectiveness are less necessary for broad surveys, effectiveness estimates will be important for detailed studies of some plant species. Unfortunately, at this point it is impossible to predict a priori which species these are.     

Relative contribution of vegetation types to regional biodiversity in Central Zagross forests of Iran

Managers in conservation biology are continually faced with the dilemma of needing to demonstrate which areas should receive conservation priority based on the diversity of species contained. Darenasab (Hashtadpahloo) forest catchment with dominated oak species in Mediterranean forests of Zagross in Iran was chosen as a case study. In order to estimate plant species richness in different vegetation types at landscape level, field method that sample both trees and herbs strata simultaneously (modified multi-scale Whittaker plots) was used to make species–area curves. Twenty-one modified multi-scale Whittaker plots (250 m² area) were located randomly in four vegetation types. Three species–area, species–log (area) and log (species)–log (area) curves models were constructed. The log (species)–log (area) model had the highest adjusted r² among others. Based on Jaccard’s coefficient, the pure oak vegetation type was the most heterogeneous (22% overlap), and the cushion plants vegetation type is the most homogeneous (29% overlap). The slope of species–area curves had the least range (0.05) and the slope of species–log (area) curves had the largest range (4.38). When the slopes of species–log (area) curves divided by mean Jaccard’s coefficient, the species–log (area) curves estimated values closest to those observed. The index of vegetation types contribution to regional diversity for determining conservation priority in off-reserve area, based on ranking of the observed mean species per plots, slopes of the species–log (area) curves, mean of Jaccard’s coefficient, mean unique species per plot, and the number of threatened species in each vegetation types were calculated. This composite index may provide a scientific method to rank vegetation types with high conservation value.     

Change in the woody floristic composition,diversity and structure from protected to unprotected savannahs in Pendjari Biosphere Reserve (Benin,West Africa)

Savannahs are widespread vegetation type in Sudanian zone of Africa. As protected areas are often assumed to be the best way to conserve biodiversity, we assessed the effectiveness of the Pendjari Biosphere Reserve in Benin, for maintaining savannah woody species composition, diversity and structure. Square plots of 900 m² were randomly established in protected and surrounding unprotected savannahs, and all woody species (dbh ≥ 1 cm) were recorded and identified. Species composition, Importance Value Index, densities, basal area and diversity indexes were assessed in relation to conservation status. The results showed that DCA based on presence/absence species data did not separate clearly protected savannahs from unprotected ones. However, some species were prominent in unprotected savannahs while others showed the same scheme in protected ones. Diversity indexes indicated a good distribution of species in the two savannah types. The woody density showed a higher value in protected than unprotected savannah at shrub layer level. The basal area was significantly higher in the protected savannah than unprotected one at the two woody layer levels. It can be concluded that biodiversity conservation in surrounding unprotected areas should be of great importance to increase biodiversity conservation by protected area whether specific actions were implemented.     

Does designation of protected areas ensure conservation of tree diversity in the Sudanian dry forest of Burkina Faso?

The importance of conservation status of the forest (protected versus unprotected) at two sites with differing human population density (high versus low) on the tree diversity of a Sudanian dry forest in Burkina Faso was studied. All woody species were recorded in 127 circular plots (area = 456.16 m²), and density, dominance, frequency, importance value indices and a variety of diversity measures were calculated to assess the species composition, structure and heterogeneity. A total of 69 species, representing 26 families and 52 genera, were found. Combretaceae, Leguminosae subfamily Caesalpinioideae and Rubiaceae were the dominant families. Neither human pressure nor forest conservation status significantly influenced the tree species richness. Stem density and basal area were significantly higher at the site with high population density than otherwise. Fisher’s diversity index revealed the unprotected forest at the site with low population density as the most diverse. We identified species with high conservation importance that should be enriched to maintain a viable population size. In conclusion, the current designation of protected areas seems inefficient at ensuring the conservation of tree diversity in the forest reserve. Thus, participatory conservation programme should be initiated.     

A comparative study of Odonata (Insecta) assemblages along an altitudinal gradient in the sierra de Coalcomán Mountains, Michoacán, Mexico

Odonate diversity in the Coalcomán Mountain Range (CMR), Michoacán State, Mexico, was surveyed, and samplings were made during 2 years in eight streams along an altitudinal gradient. Presence–absence data were analyzed using non-parametric and parametric methods. Beta and gamma diversities were estimated using Whittaker’s and Lande’s formulae, respectively. A total of 2,526 adults and 489 larvae were captured, yielding 116 species (γ diversity), 44 genera and 9 families. Five new species were discovered. The genus Argia was the most important contributor to Zygoptera diversity and total richness (γ diversity), yielding 40.4 and 14.7%, respectively. The non-parametric estimator Chao2 provided the closest theoretical estimate of species richness, and Clench’s model fit the data well (R ² ranged from 99.44 to 99.99) to explain a high proportion of the variance (98.8). We conclude that beta diversity is important at the landscape scale, supporting the hypothesis that Mexico is a beta diverse country. Our results triple the number of known species of Odonata for Michoacán. Given the considerable richness of odonates at local and landscape scales, our results support the proposal of the Coalcomán Mountain Range as a priority area for conservation and related research.     

Species richness and complementarity of beetle faunas in a mediterranean-type biodiversity hotspot

Regions of mediterranean-type climate represent most extra-tropical biodiversity hotspots, being both highly diverse and highly endangered. Though renowned for their plant richness, these regions’ insects constitute the bulk of their alpha diversities. Data on insect distribution and rarity are generally lacking for such regions, and are often considered unattainable. Intensive field inventories combined with statistical extrapolation methods can provide a sufficient understanding of alpha, beta, and gamma diversity components for application to conservation planning. These are essential to assessing the adequacy of a regional reserve network for the conservation of insect diversity. Here the beetle faunas of three protected areas spanning three major ecoregions in the California Floristic Province were inventoried and analyzed for species richness, complementarity, and uniqueness. These surveys produced collectively nearly 1,200 species from all three sites, estimated to be about 80% of their total faunas. Diversity was highly partitioned among sites, no one site containing more than 60% of the species. Dissimilarity was moderate to high for all comparisons, and all sites contained >40% unique species. Comparison of these results with those based on species of co-occurring plants reveal incongruent species richness but congruent similarities among sites. These results provide quantitative support to the perception that mediterranean insect faunas show high spatial variability. Along with online specimen level data on distribution, rarity, and seasonality, these results will help speed the incorporation of insect data into serious conservation planning.     

China Subregional Avian Endemism and Biodiversity Conservation

Richness of endemic species is considered important for biodiversity conservation and avifaunal regionalization, but no detailed studies concerning the subregional endemism have yet been done in China. Here we investigate the assemblage of China avian endemics of each avifaunal subregion, and analyze the faunal subregional species diversity, subspecific differentiation, and their relationships. The endemic species richness is found to be the highest in the Southwest Mountainous subregion where 60 species account for 57.1% of China’s 105 endemics. Seventy seven species accounting for 73.3% are monotypic. Twenty eight species (26.7%) occurred in only one subregion; the mean was 3.14±1.929 subregions, while 3 species were found widespread over 8 subregions. The number of species distributed only at one specific subregion (EOSR) is the highest in Taiwan subregion. The Southwest Mountainous subregion has the second highest EOSR and the highest richness of monotypic species, but the ratio of numbers of monotypic species or EOSR to the numbers of its subregional overall endemic species is not high in this subregion (68.3%; 10.0%). On the contrary, Taiwan subregion does not have higher richness of overall endemic species and monotypic species, but the EOSR is the highest, while the ratio of numbers of monotypic species or EOSR to the numbers of its subregional overall endemic species is also the highest among all subregions (76.2%; 71.4%). From the evidence of comparing subregional distribution of overall endemic species, EOSR, monotypic species and subspecific diversification, we may conclude that geographical isolation might be the main effect factor contributing to both subspecific diversification and avian subregional endemism in China. The higher endemic and monotypic richness in the Southwest Mountainous subregion may also indicate that the subregion’s avifaunal evolutionary and ecological isolation results from the highly diversified habitats and geographical environments as well as the historical effects from the primitive avifauna.     

Biodiversity Hotspots and Conservation Priorities in the Campo-Ma’an Rain Forests,Cameroon

Until recently, patterns of species richness and endemism were based on an intuitive interpretation of distribution maps with very limited numerical analyses. Such maps based solely on taxonomic collections tend to concentrate on collecting efforts more than biodiversity hotspots, since often the highest diversity is found in well-collected areas. During the last decades, there has been an overwhelming concern about the loss of tropical forest biological diversity, and an emphasis on the identification of biodiversity hotspots in an attempt to optimise conservation strategies. Furthermore, the concept of sites of high diversity, or hotspots, has attracted the attention of conservationists as a tool for conservation priority settings. With the development of GIS tools, geostatistics, phytosociological and multivariate analysis software packages, more rigorous numerical analyses of distributional and inventory data can be used for assessing conservation priorities. In the Campo-Ma’an rain forest, inventory data from 147 plots of 0.1 ha each and 7137 taxonomic collections were used to examine the distribution and convergence patterns of strict and narrow endemic species. We analysed the trends in endemic and rare species recorded, using quantitative conservation indices such as Genetic Heat Index (GHI) and Pioneer Index (PI), together with geostatistic techniques that help to evaluate and identify potential areas of high conservation priority. The results showed that the Campo-Ma’an area is characterised by a rich and diverse flora with 114 endemic plant species, of which 29 are restricted to the area, 29 also occur in southwestern Cameroon, and 56 others that are also found in other parts of Cameroon. Although most of the forest types rich in strict and narrow endemic species occur in the National Park, there are other biodiversity hotspots in the coastal zone and in areas such as Mont d’Eléphant and Massif des Mamelles that are located outside the National Park. Unfortunately, these areas, supporting 17 strict endemic species that are not found in the park, are under serious threat and do not have any conservation status for the moment. Taking into consideration that with the growing human population density, pressure on these hotspots will increase in the near future, it is suggested that priority be given to the conservation of these areas and that a separate management strategy be developed to ensure their protection.     

Diversity,Geographical, and Consumption Patterns of Traditional Vegetables in Sociolinguistic Communities in Benin: Implications for Domestication and Utilization<Superscript>1</Superscript>

Diversity, Geographical, and Consumption Patterns of Traditional Vegetables in Sociolinguistic Communities in Benin: Implications for Domestication and Utilization. Traditional vegetables in many African rural areas are an important part of the daily diet and economy but have been poorly documented until recently. We undertook a survey in Benin on the diversity and patterns of use of traditional vegetables by 18 sociolinguistic groups in the three major phytogeographical regions. Major groups include the Yoruba–Nagot, Fon, Bariba, Adja, Cotafon, and Ditammari. Focus groups and field visits were conducted in 49 villages. Species richness at the country level and in phytogeographical regions was estimated using species accumulation curves. Our results indicated that 245 species belonging to 62 families are used as vegetable resources all over the country. The most frequently used families include Amaranthaceae, Asteraceae, Cucurbitaceae, and Leguminoseae. About 80% of collected vegetables are wild resources; only 19% were clearly under cultivation. Herbs were the most widely consumed life form. The Guinean and the Sudanian regions exhibit similar species richness while in the Sudano–Guinean region vegetable richness is higher. The use of a species as a vegetable depends not only on socio–cultural attributes but also on geographical occurrence. Based on this inventory, we identified needs for further research and activities for both the conservation and promotion of traditional vegetables.     

The effects of land-use change on arthropod richness and abundance on Santa Maria Island (Azores): unmanaged plantations favour endemic beetles

We study how endemic, native and introduced arthropod species richness, abundance, diversity and community composition vary between four different habitat types (native forest, exotic forest of Cryptomeria japonica, semi-natural pasture and intensive pasture) and how arthropod richness and abundance change with increasing distance from the native forest in adjacent habitat types in Santa Maria Island, the Azores. Arthropods were sampled in four 150 m long transects in each habitat type. Arthropods were identified to species level and classified as Azorean endemic, single-island endemic (SIE), native, or introduced. The native forest had the highest values for species richness of Azorean endemics, SIEs and natives; and also had highest values of Azorean endemic diversity (Fisher’s alpha). In contrast, the intensive pasture had the lowest values for endemic and native species richness and diversity, but the highest values of total arthropod abundance and introduced species richness and diversity. Arthropod community composition was significantly different between the four habitat types. In the semi-natural pasture, the number of SIE species decreased with increasing distance from the native forest, and in the exotic forest the abundance of both Azorean endemics and SIEs decreased with increasing distance from the native forest. There is a gradient of decreasing arthropod richness and abundance from the native forest to the intensive pasture. Although this study demonstrates the important role of the native forest in arthropod conservation in the Azores, it also shows that unmanaged exotic forests have provided alternative habitat suitable for some native species of forest specialist arthropods, particularly saproxylic beetles.     

Hyperspectral Remote Sensing of Canopy Biodiversity in Hawaiian Lowland Rainforests

Mapping biological diversity is a high priority for conservation research, management and policy development, but few studies have provided diversity data at high spatial resolution from remote sensing. We used airborne imaging spectroscopy to map woody vascular plant species richness in lowland tropical forest ecosystems in Hawai’i. Hyperspectral signatures spanning the 400–2,500 nm wavelength range acquired by the NASA Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) were analyzed at 17 forest sites with species richness values ranging from 1 to 17 species per 0.1–0.3 ha. Spatial variation (range) in the shape of the AVIRIS spectra (derivative reflectance) in wavelength regions associated with upper-canopy pigments, water, and nitrogen content were well correlated with species richness across field sites. An analysis of leaf chlorophyll, water, and nitrogen content within and across species suggested that increasing spectral diversity was linked to increasing species richness by way of increasing biochemical diversity. A linear regression analysis showed that species richness was predicted by a combination of four biochemically-distinct wavelength observations centered at 530, 720, 1,201, and 1,523 nm (r ² = 0.85, p < 0.01). This relationship was used to map species richness at approximately 0.1 ha resolution in lowland forest reserves throughout the study region. Future remote sensing studies of biodiversity will benefit from explicitly connecting chemical and physical properties of the organisms to remotely sensed data.     

Plant diversity in sacred forest fragments of Western Ghats: a comparative study of four life forms

The effect of fragmentation on different life forms within tropical forest plant communities is poorly understood. We studied the effect of degree of fragmentation and surrounding matrix on trees, lianas, shrubs and epiphytes in tropical forest fragments of Kodagu, Western Ghats, India. These fragments exist as sacred groves amidst a highly modified agricultural landscape, and have been preserved by the religious sentiments of local communities. Plants were sampled at two sites in continuous forests and 11 forest fragments. A total of 122 species of trees, 29 species of lianas, 60 species of shrubs and 66 species of epiphytes were recorded. Trees exhibited a significant species–area relationship (R ² = 0.74). Richness estimates after controlling for stem density (rarefaction) revealed that observed species–area relationship was not an artefact of passive sampling. Variation in species richness of the other three groups was explained by stem density and structural diversity. Linear distance from the reserve forest did not explain any variation in species richness. All life forms exhibited significant nested pattern. Trees were nested along the area gradient while nestedness in the other three groups showed evidence in support of habitat nestedness. The four life forms thus responded variably to degree of fragmentation. Our study revealed that 74% of the regional diversity for trees was contributed by diversity among plots, highlighting the importance of inter-patch habitat diversity in maintaining the total regional species pool. We conclude that trees alone cannot serve as good indicator for taking appropriate conservation measures to mitigate species loss resulting from habitat fragmentation.