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Protected areas as refugias for genetic resource: Are sandal genetic resources safe in our sanctuaries?
No full textSandal (Santalum album L.) is one of the most economically important tree species indigenous to peninsular India. The species is extracted for its heartwood and oil. The sandal genetic resources in the country are threatened by a variety of factors including logging of the trees, poaching and due to large scale changes in land use. Analyzing long-term records of extraction, in Kamataka, India, Meera et al. (2000) and Nageswara Rao et al. (1999) showed a substantial decline in the total quantity of sandalwood extracted over the years. The decrease in availability of sandal is also mirrored in the reduction of sandalwood supplied to the factories (Meera et aI., 2000). It is feared that unless these losses are checked, it could lead to an irreversible loss of the sandal genetic resources from the country (Nageswara Rao et al., 1999; Uma Shaanker et al., 2000)
Checklist of orchids from a mid elevation evergreen forest at Kakachi-Kodayar, Kalakkad-Mundanthurai Tiger Reserve, Agasthyamalai, southern Western Ghats
Get PDFThe forests at Kakachi-Kodayar (77o 24’N & 8o 32’E, 1200-1550m), in Kalakad-Mundanthurai Tiger Reserve, part of Agasthyamalai range in the southern part of the Western Ghats (see map) support one of the species-rich forest site (Ganesh et al., 1996).Though some part of the forest is lost to the dam, plantations, logging and Ochlandra spp. (reed bamboo) extraction, it still supports dense contiguous forest of subtropical wet evergreen, subtropical montane and shola forest types surrounded by grasslands
Dynamics of sediment discharge in relation to land-use and hydro-climatology in a humid tropical watershed in Costa Rica
No full textHydrology in humid tropical regions is often characterized by considerable natural variability and uncertainty. Hydrologic and land-use data from the Terraba basin in Costa Rica are used to analyze dynamics in sediment discharge processes during the period 1971–1993.Time-series of log transformed sediment concentration and flow are analyzed with a Bayesian dynamic linear regression model (DLM) to detect changes in the sediment–flow relationship over time. Annual time-series of estimated sediment discharge based on the DLMs were regressed against various hydro-climatic variables based on the Southern Oscillation Index (SOI), rainfall, stream flow and rainfall erosivity. Hydro-climatic variables such as rainfall, stream flow and rainfall erosivity were also regressed against SOI. The results from the regression models, the presence of trends in the DLM slope and other hydro-climatic parameters for each sub-basin were used to compare the hydro-climatic and sediment response characteristics of the sub-basins.
Over 60% of the variability in hydro-climatic variables like rainfall, rainfall erosivity and stream flow is explained by SOI but less than 40% for sediment discharge measured at the basin mouth. The clustering of stations and sub-basins with respect to sediment discharge responses is different from that based on hydro-climatic characteristics. Stations or sub-basins corresponding to areas with large rates of deforestation and/or agricultural intensification and earthquake related soil disturbance tend to fall in one cluster. These sub-basins are characterized by an increase in the sediment–flow regression slope over time, and weaker relationship between sediment discharge and hydro-climatic variables such as SOI, rainfall and flow. In sub-basins undergoing rapid land-surface changes, variability in sediment supplies accounted for an estimated 50–90% of the variability in annual sediment discharge. The methods described in this paper can be used to analyze many existing hydrologic time-series to detect land-use effects on watershed hydrolog
Returns to investment in conservation: Disaggregated benefit-cost analysis of the creation of a wildlife sanctuary
No full textTropical forest ecosystems provide a wide range of benefits to mankind. Economists have categorised these into use and non-use values, further categorised into direct and indirect use on the one hand and option, bequest and existence value on the other. Estimating the 'total economic value' of forests has become a popular topic of research and discussion in the conservation community. Theory and techniques for estimation of the nonusebenefits have dominated recent research. In the process, however, most valuation exercises have overlooked two fundamental issues: a) the 'so what?' problem, i.e. estimating the economic value of something in isolation is not very useful, and b) the 'aggregation problem', i.e. the fact that the supposed 'aggregate social welfare function' has no objective basis. These
problems need to be addressed if economic valuation is to provid
Conservation of bamboo genetic resources in Western Ghats: Status, threats and strategies
No full textBamboo forms a major nonwood forest produce of the tropical forests of south and southeast Asia and provides livelihood requirements to a large number of forest fringe communities. Besides the traditional user groups – the artisans, bamboo is much sought by the paper and pulp industry. Together, the demand on the bamboo resources is substantial and it is projected that in the years to come, the demand would soon outrun the stock. This is particularly true in countries such as India where almost all the requirements of bamboo are met from the natural populations. The indiscriminate extraction of bamboo
coupled with the large-scale habitat loss have seriously
endangered the genetic resources of bamboo. In this chapter we review the status and threats to the bamboo genetic resources in the central Western Ghats, India and discuss the conservation of the genetic resources of two economically important species of bamboo, Bambusa arundinacea and Dendrocalamus strictus. Our study shows that the two species exhibit strikingly contrasting spatial patterns in the distribution of genetic diversity and that accordingly, strategies for the conservation of the genetic resources of the two species need to be addressed separately
Regeneration dynamics of a wet evergreen forest, southern Western Ghats, India
No full textThe evergreen forests of Agasthyamalai in south Western Ghats, India have the highest percentage of endemic species in the Western Ghats. Despite its richness and importance, there are very few studies on the long-term demography and population changes of the tree species in the evergreen forests of Agasthyamalai (Parthasarthy, 2001; Ganesh et al., 1996)
Mapping biodiversity from the sky
No full textAn efficient conservation planning is contingent upon assessment and mapping of biological diversity to identify the local, regional and global hot spots (Wilson, 2000). The existing methods to map biodiversity on a large spatial scale are time consuming as they require intensive ground surveys. In this paper we demonstrate the use of remote sensing imagery to assess and map the biodiversity in a tropical ecosystem and discuss the use of this technique in monitoring as well as conservation planning
A regional approach for the conservation of the biological diversity of the Western Ghats
No full textBiological resources of a region constitute a range of layers such as intraspecific genetic diversity, diversity of species, their assemblages and interactions and, the diversity of ecosystems of the region (Figure 1). A
systematic regional level conservation plan ought to incorporate steps to conserve all these components; but most of the present day conservation efforts are usually focused on specific layers rather than taking a comprehensive approach. Consequently, most of these programs are often overlapping, redundant and are cost ineffective in conserving the biological diversity of a region. Systematic conservation plans that aim at an effective conservation of as many components as possible with least overlap and minimal resources are being rigorously sought for (Ganeshaiah et aI., 1999, 2001; Margulis and Pressey, 2001). In this paper we propose a program aime
Effect of weeds Lantana camara and Chromelina odorata growth on the species diversity, regeneration and stem density of tree and shrub layer in BRT sanctuary
Get PDFA study was undertaken in Biligiri Rangan hills Temple wildlife sanctuary, Karnataka covering an area of 540 km2 by laying 134 plots measuring 80 m × 5 m at 2-km intervals over the sanctuary, to understand the influence of two weeds, Lantana camara and Chromelina odorata, on species richness and stem density. All stems above 1 cm DBH were enumerated. Plots were classified based on the presence and absence of Lantana and Chromelina. Species richness and stem density were high in the plots infested with Lantana compared to control and lower species richness was recorded in plots infested with Chromelina compared to Lantana. It is argued that Lantana may not suppress the growth of other species; it probably grows in the plots with more moisture, preferred by many other species
Response of some Scolytids and their Predators to Ethanol and 4- Allylanisole in Pine Forests Of Central Oregon
No full textLindgren multiple funnel traps were set up in pine forests of central Oregon to determine the response of scolytid bark beetles to ethanol and 4-allylanisole (4AA). Traps were baited with two release rates of ethanol (4.5 or 41.4 mg/hr) and three release rates of 4AA (0, 0.6, or 4.3 mg/hr) in a 2 × 3 factorial design. All traps also released a 1:1 mixture of α- and β-pinene at 11.4 mg/hr. Of 13,396 scolytids caught, Dendroctonus valens made up 60%, Hylurgops spp. 18.5%, Ips spp. 16%, Hylastes spp. 1.8%, Ganthotrichus retusus 0.9%, and bark beetle predators another 2.8%. Increasing the release rate of ethanol in the absence of 4AA increased the number of most scolytid species caught by 1.5–3.7 times, confirming its role as an attractant. Ips latidens, Temnochila chlorodia, and clerid predators were exceptions and did not show a response to higher ethanol release rates. Release of 4AA at the lowest rate inhibited attraction of most scolytids, with a significant reduction in G. retusus, Hylastes macer, and Hylurgops porosus when compared to traps without 4AA. A high release rate of 4AA further inhibited responses for most beetles compared to low 4AA. Seven species were significantly deterred by high 4AA, including the latter three, and Hylastes longicollis, Hylastes nigrinus, Hylurgops reticulatus, and Ips latidens. Exceptions include Hylurgops subcostulatus, which was significantly attracted to both low and high 4AA, and I. pini, which was attracted to low and high 4AA in combination with low ethanol, but unaffected by either release of 4AA with high ethanol. Dendroctonus valens was significantly attracted to low 4AA and unaffected by high 4AA. Predators appeared to be less inhibited by 4AA than most bark beetles. Although 4AA can deter the attraction of some secondary bark beetles to ethanol in combination with α- and β-pinene, this inhibition could be weakened for certain species by increasing ethanol release rates. 4-Allylanisole may have some utility for managing the behavior of secondary bark beetles sensitive to this compoun