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No full textThere are several records on the avifauna of Billigiri Rangaswamy Temple Wildlife Sanctuary. First and foremost is by British naturalist, RC. Morris who published a couple of papers on avifauna of Biligiri Rangaswamy Temple Wildlife Sanctuary (Morris 1927, 1939). Salim Ali surveyed erstwhile Mysore district as a part of his effort to document bird life of India and covered'Billigiri Rangaswamy Temple Wildlife Sanctuary (1942 a, b; 1943 a,b,c). Since then, there have been several surveys and .additions to the bird list
(Baskaran 1992, Karthikeyan et til. 1995, Srinivasa et al. 1997, }ayadeva, (pers. Corom.) and Uttangi, 2000). Recently Aravind et at. (2001) qJade several new additions to the bird list J of Biligiri Rangaswamy Temple Wildlife Sanctuay
Patterns of accumulation of camptothecin, an anti-cancer alkaloid in Nothapodytes nimmoniana Graham., in the Western Ghats, India: Implications for identifying high-yielding sources of the alkaloid
Get PDFCamptothecin, a monoterpene indole alkaloid, is regarded
as one of the most promising anticancer drugs of the
twenty-first century. Among the various plant sources,
the highest yields of the alkaloid are reported from
Nothapodytes nimmoniana (Icacinaceae), a small tree
distributed in the Indian subcontinent. Because of the
enormous demand for the chemical worldwide, there has been an indiscriminate extraction of the trees from many parts of India, especially from the Western Ghats, a mega-diversity forest range along the western coast of
India. Recently the tree has been assigned a vulnerable
status. In an effort to conserve the remaining populations of the species and to identify high-yielding sources of the alkaloid, attempts are being initiated in chemically profiling the species. As a first step in this direction, we have attempted to establish the general patterns of accumulation of camptothecin in N. nimmoniana across individuals, plant parts, plant size and sex of plants, in the Western Ghats. Individual trees with as high as 100 per cent greater camptothecin content than hitherto reported have been found. The study indicates the potentiality of further screening populations of N. nimmoniana to identify high-yielding sources that can be used for developing in vitro production systems or for establishing high-yielding clonal populations
Impact of iron ore mining on suspended sediment response in a tropical catchment in Kudremukh, Western Ghats, India
No full textAvailable secondary suspended sediment data from the 1980s was analyzed together with new data collected during 2001–2003 at instrumented sites upstream and downstream of open-cast mining activities (∼4.2 km2) in an enclosure within the Kudremukh National Park in south India. More than 50% of the suspended sediment load in both the Bhadra River and Bhadra Reservoir comes from mining-affected lands that occupy 150 mm and hourly intensities exceeding 20 mm. One hundred and nine such episodic events occurred between 1990 and 2001 alone. A conservative estimate of the total suspended sediment load in the Bhadra River after mining commenced in the 1980s is 1.37 × 106 Mg, although the actual value could be considerably higher, up to 107 Mg. Comparison of historic data and another study in 1994, with recent measurements confirm that mining and associated activities in Kudremukh National Park are the greatest sources of sediment entering the Bhadra River; and the Bhadra river carries considerably more sediment now than before mining started damaging riverine ecosystems and disrupting downstream water resources
Prioritisation of conservation areas in the Western Ghats, India
No full textAreas of high conservation value were identified in the Western Ghats using a systematic
conservation planning approach. Surrogates were chosen and assessed for effectiveness
on the basis of spatial congruence using Pearson’s correlations and Mantel’s tests. The
surrogates were, threatened and endemic plant and vertebrate species, unfragmented
forest areas, dry forests, sub-regionally rare vegetation types, and a remotely sensed surrogate
for unique evergreen ecosystems. At the scale of this analysis, amphibian richness
was most highly correlated with overall threatened and endemic species richness,
whereas mammals, especially wide-ranging species, were better at capturing overall animal
and habitat diversity. There was a significant relationship between a remote sensing
based habitat surrogate and endemic tree diversity and composition. None of the taxa or
habitats served as a complete surrogate for the others. Sites were prioritised on the basis
of their irreplaceability value using all five surrogates. Two alternative reserve networks
are presented, one with minimal representation of surrogates, and the second with 3
occurrences of each species and 25% of each habitat type. These networks cover 8%
and 29% of the region respectively. Seventy percent of the completely irreplaceable sites
are outside the current protected area network. While the existing protected area network
meets the minimal representation target for 88% of the species chosen in this study
and all of the habitat surrogates, it is not representative with regard to amphibians,
endemic tree species and small mammals. Much of the prioritised unprotected area is
under reserve forests and can thus be incorporated into a wider network of conservation
areas
Science in the wilderness: the predicament of scientific research in India’s wildlife reserves
Get PDFEcology and allied scientific disciplines aim to understand patterns and processes pertaining to wild species, their ecosystems and their relationships with humans. India’s wildlife reserves are important ‘living laboratories’ for these disciplines. Today, there is a disturbing trend across India where scientists are increasingly denied access to wildlife reserves for scientific research or are seriously impeded, without scope for redress. Although official wildlife management rhetoric emphasizes the need for scientific research, in reality, it is viewed as undesirable and permitted, if at all, as a concession, subject to the discretion of individual forest officials. With no enabling legislative or policy framework to promote and apply science in our wildlife reserves, we are concerned that the future of many scientific disciplines in India is being jeopardized. Here, we provide an analysis of this issue and outline steps needed to promote scientific research in our natural areas
Pollination biology of Aristolochia tagala, a rare species of medicinal importance
Get PDFFloral phenology, pollination biology and breeding system
were studied in Aristolochia tagala Cham (Aristolochiaceae) grown under ex situ conditions. The flower exhibits structural features typical of fly-trap mechanism described for other Aristolochia species. Flowers show pronounced protogyny. Stigmas are receptive at anthesis and remain so for 24 h. Anthers dehisce 45–
48 h after anthesis by which time stigma receptivity is
lost. Chironomid fly (Diptera) is the pollinator. Attracted by the odour and colour of the flower, the flies enter it and are detained in the chamber of the perianthtube (where the anthers and stigma are located)
for nearly 50 h. Their escape is prevented by the presence of dense downward-pointing hairs in the perianth
tube. The nectaries provide food to the insects. Following anther dehiscence, the thorax of the flies
becomes loaded with sticky pollen grains. Hairs on the
inner wall of the perianth tube wither and facilitate
the exit of the flies. When a fly carrying the pollen load enters a fresh flower, it brings about pollination.
Manual pollinations showed that the species permits
geitonogamous pollination. The percentage of fruit set
in manually pollinated flowers is higher than that resulting from open pollination, confirming that pollination is a limitation for fruit set in the ex situ-grown population. Nevertheless, fruit and seed set is sufficiently high for ex situ conservation purposes
Ruminant-mediated Seed Dispersal of an Economically Valuable Tree in Indian Dry Forests
No full textRuminant-mediated seed dispersal, an understudied process in tropical forests, was examined via Phyllanthus emblica–Axis axis interaction. A captive Axis deer regurgitated intact P. emblica seeds after retaining them in the rumen for 7–27 h. At Rajaji National Park, a considerable fraction (22%) of deer-regurgitated P. emblica seeds germinated, although lower than unconsumed seeds (72%). The size and strength of seeds like P. emblica might ensure that ruminants regurgitate them intact instead of defecating them
Issues in Restructuring
No full textThere is a need to reiterate the interconnectedness of the biophysical, socio-economic, and institutional aspects of watershed development from within a larger conceptual and normative framework for natural resource-based Watershed development is increasingly seen as the lynchpin of rural development in dry land areas – one that integrates sectors and provides the foundation for subsequent development. Though some of the notable examples of watershed development appear to offer a way out of stagnation and degradation for all those areas that development had seemingly bypassed, various reviews and studies show that overall the performance has not kept pace with the expectations. The programme needs to be restructured significantly, if the watershed development approach has to deliver what it promises. Such a restructuring must clearly embrace a normative framework that treats livelihoods, productivity, sustainability, equity and decentralised governance as its central concerns, and must be based on strategies that respond to the varying socio-ecological contexts and past experiences with implementation
Population Growth, Human Development, and Deforestation in Biodiversity Hotspots
No full textHuman population and development activities affect the rate of deforestation in biodiversity hotspots. We quantified the effect of human population growth and development on rates of deforestation and analyzed the relationship between these causal factors in the 1980s and 1990s. We compared the averages of population growth, human development index (HDI, which measures income, health, and education), and deforestation rate and computed correlations among these variables for countries that contain biodiversity hotspots. When population growth was high and HDI was low there was a high rate of deforestation, but when HDI was high, rate of deforestation was low, despite high population growth. The correlation among variables was significant for the 1990s but not for the 1980s. The relationship between population growth and HDI had a regional pattern that reflected the historical process of development. Based on the changes in HDI and deforestation rate over time, we identified two drivers of deforestation: policy choice and human-development constraints. Policy choices that disregard conservation may cause the loss of forests even in countries that are relatively developed. Lack of development in other countries, on the other hand, may increase the pressure on forests to meet the basic needs of the human population. Deforestation resulting from policy choices may be easier to fix than deforestation arising from human development constraints. To prevent deforestation in the countries that have such constraints, transfer of material and intellectual resources from developed countries may be needed. Popular interest in sustainable development in developed countries can facilitate the transfer of these resources
Interactions between non-flying mammals and flowers of Cullenia exarillata Robyns (Bombacaceae), a canopy tree from the wet forests of Western Ghats, India
Get PDFMany non-flying mammals help in the pollination of plant species in tropical forests. However, this remains
poorly documented from India. Here we demonstrate with Cullenia exarillata, a canopy tree in the Western Ghats, how a wide range of visitors frequent flowers of the tree and how among them a few select mammals are important in pollination. Since Cullenia also uses bats as a pollinating vector, we further discuss how the dual strategy of using non-flying mammals and bats could have evolved in the wet forests of the Western Ghats