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High resolution satellite imagery for tropical biodiversity studies: the devil is in the detail
No full textWhile high resolution satellite remote sensing has been hailed as a very useful
source of data for biodiversity assessment and monitoring, applications have been more
developed in temperate areas. The biodiverse tropics oVer a challenge of an altogether
diVerent magnitude for hyperspatial and hyperspectral remote sensing. This paper examines
issues related to hyperspatial and hyperspectral remotely sensed imagery, which constitutes
one of the most potentially powerful yet underutilized sources of for tropical
research on biodiversity. Hyperspatial data with their increased pixel resolution are possibly
best suited at facilitating the accurate location of features such as tree canopies, but less
suited to the identiWcation of aspects such as species identity, particularly when spatial
resolution becomes too Wne and pixels are smaller than the size of the object (e.g., tree
canopy) being identiWed. Hyperspectral data on the other hand, with their high spectral
resolution, can be used to record information pertaining to a range of critical plant properties
related to species identity, and can be very eVective used for discriminating tree species
in tropical forests, despite the greater complexity of such environments. There remains a
glaring gap in the easy availability of hyperspectral and hyperspatial satellite data in the tropics
due to reasons of cost, data coverage, and security restrictions. Stimulating discussion
on the applications of this powerful, but underutilized tool by ecologists, is the Wrst step i
Value of deforestation?
No full textThe Union government has drafted the Compensatory Afforestation Bill, 2008 to establish a compensatory
afforestation fund. Revenues collected from agencies
that divert forests (even protected ones) for nonforest
use will be pooled into this corpus. Net present value (npv) has been adopted as an economic tool to calculate the compensatory fiscal value of diverted forests. But there are two question marks over the move. Firstly, can forests, especially the protected ones, which provide vital ecological and cultural services, be assigned an economic value in lieu of their diversion? Second, is NPV an appropriate fiscal tool to calculate the 'compensatory'value of functioning physical entities such as forests
Management Regimes, Property Rights, and Forest Biodiversity in Nepal and India
No full textThis article compares a range of initiatives aimed at involving people in the management of forest resources in Nepal and India. In Nepal, we focus on three categories of state-initiated programs: community forestry,the parks’ buffer zone program, and leasehold forestry. In
the southern Indian state of Karnataka, we study the state initiated Joint Forest Planning and Management program along with older institutions of leaf manure forests (Soppina betta) and historical sacred forests (Kans). We conclude that state-initiated approaches to involving communities have been limited, at best, promote standardized and relatively inflexible management practices, and lead to partial improvement in biodiversity and people’s livelihoods. When management is initiated and owned by the community, as in the case of sacred groves in India, and when other conditions are appropriate, communities can have the opportunity to demonstrate their capacity for putting effective and adaptive conservation practices in place
Forest fragmentation and regrowth in an institutional mosaic of community, government and private ownership in Nepal
No full textThis study analyzes forest change in an area of Nepal that signifies a delicate balance between sustaining the needs and livelihood of a sizable human population dependent on forest products, and an effort to protect important wildlife and other natural resources. The study area, a portion of the Chitwan valley district of Nepal, represents what may be becoming a common institutional mosaic in many countries of the world who have a population reliant on forest products for their livelihood: (1) a national park; (2) a designated park buffer involving participatory forest management programs; (3) scattered patches of designated community forest; and (4)large areas of adjacent landscape made up of mostly private landholdings under agricultural practices. Utilizing Landsat images from 1989 and 2000, we analyze land cover change in each of these management
zones using landscape ecology metrics and quantifying proportional distributions of land cover categories. Our results show significant differences in terms of land cover dynamics and landscape spatial pattern between these land ownership classes. These findings indicate that community-based institutions (participatory management programs in the park buffer and the designated community forests) are capable of halting or even reversing trends in deforestation and forest fragmentation
Reproductive strategies of Strobilanthes kunthianus, an endemic, semelparous species in southern Western Ghats, India
No full textStrobilanthes kunthianus (Acanthaceae) is a semelparous species with synchronized flowering and mast seeding
once in 12 years. As semelparous plants have only one chance to reproduce, they are expected to develop effective strategies to prevent reproductive failure. The reproductive strategies of S. kunthianus were investigated by studying the floral traits, pollination biology, and breeding system that are critical for reproductive success. The species exhibits a series of floral traits: (1) gregarious flowering attracts a large number of Apis cerana indica, the major pollinator; (2) the stigma is sensitive to touch by the pollinator; in fresh flowers, the receptive surface faces the entry path of the incoming bee, facilitating pollen deposition; as an immediate response, the stigma curves backwards moving the receptive surface away from the path of the exiting bee, thus preventing autogamy and interference in pollen transfer; (3) flowers remain fresh for 2 days with receptive stigma and nectar and pollen reward. These traits render the species 100% pollination efficient to ensure a high seed set. As the species is self-compatible, the prevailing high degree of geitonogamous pollinations does not interfere with fruit set. The
evolution of the adaptive floral traits has facilitated mast seeding in the species
Do Parks Work? Impact of Protected Areas on Land Cover Clearing
No full textThis paper evaluates the impact of protected areas on
land-cover clearing, using a metadata analysis of information
on 49 locations from 22 countries. Protected
areas had significantly lower rates of clearing in comparison
to their surroundings. In addition, protected areas
had also significantly lowered rates of clearing within their
boundary following initiation of protection. Thus, protected
areas do appear to be effective at limiting overall landcover
clearing. There was some variation in the rates of
clearing across regions, where most protected areas from
North America and Europe showed positive rates of landcover
change, while protected areas from Asia had the
highest rates of land-cover clearing. While most protected
areas from North America and Europe involved a
relatively smaller number of actors, a greater number of
actors and drivers of clearing was implicated in protected
areas from Asia, Africa, and Latin America, indicating the
increased difficulties faced by park management in these
regions. In contrast, country income levels and the
International Union for the Conservation of Nature and
Natural Resources category of protection did not appear
to impact the likelihood of land-cover clearing in protected
areas
Ecosystem impacts of disturbance in a dry tropical forest in southern India
No full textIndian forests provide a multitude of services to vast populations. Common human activities including livestock grazing, fuelwood extraction and burning have the potential to impact forest ecosystem structure and function. The effects of these activities on vegetation, ecology and soil properties were investigated in Bandipur National Park (BNP) in southern India. Data were collected from 200 sites in four watersheds within the park. Sample sites spanned a degradation gradient measured by a field disturbance index (FDI). This paper focusses on the impacts on vegetation structure, diversity and composition, and integrates impacts on soil. Shrub and tree species were inventoried and evaluated in plots 10-m in diameter. The tree layer was dominated by Anogeissus–Emblica–Tectona species. The understory was dominated by invasives Chromolaena odorata and Lantana camara, and native Gymnosporia emarginata. Vegetation plot heights, canopy cover and tree diameters were negatively correlated with field disturbance resulting in stunted forest stature in degraded sites. Vegetation composition in degraded watersheds was dominated by small woody tree species and a greater diversity of shrub species. Ordination analysis was used to integrate soil data with vegetation and disturbance, revealing that deciduous forest in the park is degrading to scrub forest along with negative impacts on soil characteristics. Consequences of services currently enjoyed by local populations are discussed. Copyright © 2008 John Wiley & Sons, Ltd
Proximity to forests drives bird conservation value of coffee plantations: implications for certification
No full textWidespread loss of primary habitat in the tropics has led to increased interest in production landscapes for biodiversity conservation. In the Western Ghats biodiversity hotspot in India, shade coffee plantations are located in close proximity to sites of high conservation value: protected and unprotected forests. Coffee is grown here under a tree canopy that may be
dominated by native tree species or by nonnative species, particularly silver oak (Grevillea robusta). We investigated the influence of properties at the local scale and the landscape scale in determining bird communities in coffee plantations, with particular emphasis on species of conservation priority.We used systematic point counts in 11 coffee plantation sites and analyzed data in a randomized linear modeling framework that addressed spatial autocorrelation. Greater proportion of silver oak at the local scale and distance to contiguous forests at the landscape scale were implicated as factors most strongly driving declines in bird species richness and abundance, while increased basal area of native tree species, a local-scale variable, was frequently related to increased bird species richness and abundance. The influence of local-scale variables increased at greater distances from the forest. Distance to forests emerged as the strongest predictor of declines in restricted-range species, with 92% reduction in the abundance of two commonly encountered restricted-range species (Pompadour Green Pigeon and Yellow-browed Bulbul) and a 43% reduction in richness of bird species restricted to Indian hill forests within 8 km of forests. Increase in proportion of silver oak from 33% to 55% was associated with 91% reduction in the abundance of one commonly encountered restricted-range species (Crimson-fronted Barbet). One conservation strategy is providing incentives to grow coffee in a biodiversity-friendly manner. One implication of our study is that plantations located at varying distances to the forest cannot be compared fairly for biodiversity friendliness by existing certification methodology. Another is that conservation of existing forests at the landscape scale is essential for maintaining higher biodiversity in coffee plantations. Incentive schemes that promote conservation of remnant forests at the landscape scale and biodiversity-friendly practices locally and that relate to coffee communities as a whole rather than individual planters are likely to be more effective
Contrasting spatial patterns of distribution of genetic diversity in two important bamboo species in the Central Western Ghats, India
No full textBamboo fonns an important component of the tropical forests of South and Southeast Asia and provides livelihood requirements to a large number of forest fringe communities. Large-scale destruction of habitats and over-harvesting of many economically important species of barn boo has led to irreversible loss of its genetic diversity. Thus, in recent years there has been an increasing concern over the conservation of genetic resources of bamboo. However, for most species of bamboo, critical infonnation on the extent of intra-specific genetic variability of the populations is unavailable. In this direction, we have examined the population genetic variability of Dendrocalamus strictus and Bambusa bambos, the most important species of bamboo in the Central Western Ghats, India. The study shows that the two species exhibit strikingly contrasting patterns in the distribution of genetic variability. While the diversity of D. strictus was higher in the northern latitudes, the diversity of B. bambos was higher in the southern latitudes. These findings could have important implications for conservation and management of genetic
resources of bamboo in the Central Western Ghats, India
Ecology and Behaviour of An Endemic Treeshrew Tupaia Nicobarica Zelebor 1869 on Great Nicobar Island, India
No full textThe Nicobar treeshrew Tupaia nicobarica is an endemic mammal restricted in its distribution to Great and Little
Nicobar islands in the Andaman Sea. This article aims to report basic information on the ecology and behaviour as
well as a preliminary population assessment of this species on Great Nicobar Island. Nicobar treeshrews spend more than 60% of the day foraging, followed by resting or sleeping (12%). The proportion of time spent on major activities was significantly different across different time periods, with much of the feeding activity in the mornings and evenings. Nicobar treeshrews were observed largely solitarily or as breeding pairs. Observations on mating, aggression and vocalisation are also reported. Most of the ecological and behavioural traits are shared with one or more species of Tupaia in the region. Observations on this species point to its extreme arboreality in comparison to other Tupaia. The species also exhibited a high degree of insectivory during the study period. A combination of these two traits makes
this species one among a handful of nonvolant foliage gleaning insectivorous small mammals that exist in the world today. The species was observed in moderate numbers both in the littoral forests as well as in the rain forests in the interior of the island. Although formally classified as endangered (on account of its restricted range), the species is common locally. The current status of the species seems to be stable in the Great Nicobar Island which has some of the best preserved forests in India