572 research outputs found
Sort by
A Structure for Environment Governance: A Perspective
No full textGoverning India’s environment in a way that strikes the right balance between sustainability, local livelihoods and developmental pressures has become an increasingly challenging task. Conflicts and controversies are emerging almost every week, what with projects reportedly being submitted for clearance at the rate of more than
150 per month. In this context, the move by the Ministry of Environment and Forests (MoEF) to restructure the environmental governance structure is welcome, as also the invitation for public comment on the specific idea of a National Environmental Protection Agency (NEPA)
(MoEF 2009
Assessing Plant Diversity in a Dry Tropical Forest: Comparing the Utility of Landsat and Ikonos Satellite Images
No full textWhile high expectations have been raised about the utility of high resolution satellite imagery for biodiversity assessment, there has been almost no empirical assessment of its use, particularly in the biodiverse tropics which represent a very challenging environment for such assessment challenge. This research evaluates the use of high spatial resolution (IKONOS) and medium spatial resolution (Landsat ETM+) satellite imagery for assessing vegetation diversity in a dry tropical forest in central India. Contrary to expectations, across multiple measures of plant distribution and diversity, the resolution of IKONOS data is too fine for the purpose of plant diversity assessment and Landsat imagery performs better
Ficus trees As Components of Rained Agrarian Systems in Mandy District of Karnataka
Get PDFMandya district in southern dry agroclimatic zone of Karnataka harbours a remarkable abudance and diversity of trees of ficus genus in dryland fi elds. Various species
identified from a survey of hundred farmlands in the district are enlisted in the is communication, along with farmers' perception on direct benefits of these trees in
agroforestry systems
Monitoring systems outdated and protectionist
No full textNone of Jeffrey Sachs and colleagues' cited monitoring systems (Nature 466, 558-560; 2010) meets the innovation requirements for the comprehensive monitoring of agro-ecological zones worldwide.
Information technologies now offer an array of approaches and tools for rapid collation, organization and dissemination of interactive data, but most monitoring systems are outdated and protectionist. They are often developed and maintained in isolation, which severely reduces the utility of the data and information gathered. New platforms and different ways of collecting information will be required to build a global system
The impact of forest use and reforestation on soil hydraulic conductivity in the Western Ghats of India: Implications for surface and sub-surface hydrology
No full textThere is comparatively limited information in the humid tropics on the surface and sub-surface permeability
of: (i) forests which have been impacted by multi-decades of human occupancy and (ii) forestation
of land in various states of degradation. Even less is known about the dominant stormflow pathways for
these respective scenarios. We sampled field saturated hydraulic conductivity, K* at 23 sites at four
depths (0 m, n = 166), (0.10 m, n = 139), 0.45–0.60 m, n = 117, (1.35–1.50 m, n = 117) under less disturbed
forest (Forest), disturbed production forest of various local species (Degraded Forest) and tree-plantations
(Acacia auriculiformes, 7–10 years old, Tectona grandis, �25–30 years old, Casuarina equisetifolia, 12 years
old) in the Uttar Kannada district, Karnataka, India, in the Western Ghats. The sampling strategy was also
undertaken across three physiographic blocks and under three main soil types. Subsequently the determined
K* were then linked with rainfall intensity–duration–frequency (IDF) characteristics to infer the
dominant stormflow pathways.
The Degraded Forest shows an order of magnitude decline in K* at the surface as result of human impacts
at decadal to century time scales. The lowest surface permeability is associated with the Degraded Forests
over the Laterite (Eutric Nitosols and Acrisols) and Red soils (Eutric Nitosols) and infiltration-excess overland
flow, IOF probably occurs. Further there is a progressive decline in K* with depth in these soils supporting
Degraded Forests. The A. auriculiformes plantations over the Red and Lateritic soils are
progressively restoring the near-surface K*, but their K* still remain quite low when compared to the less
disturbed forest permeability. Consequently these plantations still retain the ‘memory’ from the previous
degraded state. In contrast the permeability of the Black soils (Vertisols) are relatively insensitive to T.
grandis plantations and this soil group has a very low K*, irrespective of land cover, so that IOF likely prevails.
Overall, the Laterites are the most variable in K* when compared to the other soil groups. Thus when
compared to other studies, IOF is probably more prevalent in this region. More especially so, when taking
into account the marked reduction in surface K* during the wet season when compared to dry season
measurements. In addition, we have demonstrated the potential for the ‘infiltration – trade-off’ hypothesis
to be realized in this landscape under certain conditions of land degradation and restoration. It is
most relevant to the combination of degraded sites and A. auriculiformes plantations on Red or Laterite
soils using the less disturbed forests as the baseline. The intensity of forest use and effects of monoculture
plantations on soil ecology (relative to native, mixed forests) is likely to be the critical factor in affecting
surface K* over time. Predicted changes in the intensity of rain events in the future is likely to enhance
overland flow on degraded sites on all soils and especially on Black soils, and restoration efforts by all
stake-holders, preferably using native or non-invasive species, are needed to address this concern
Cataloguing life in India: the taxonomic imperative
Get PDFTaxonomy, the science of discovering, describing and naming new species has become critically important in this era of declining biodiversity. Cataloguing species
is fundamental to conservation and sustainable use of biodiversity. Taxonomy also forms the basis of elucidating evolutionary relationships among agricultural
crops, parasites, pathogens and insect pests. Many pharmaceutical products are based on plants and the indigenous systems of medicines are basedon our ability to accurately classify and describe living organisms. Thus taxonomy plays a vital role in the human
well-being
Evaluation of methods to estimate foliage density in the understorey of a tropical evergreen forest
Get PDFFoliage density and leaf area index are important vegetation structure variables. They can be measured
by several methods but few have been tested in tropical
forests which have high structural heterogeneity.In this study, foliage density estimates by two indirect methods, the point quadrat and photographic methods,were compared with those obtained by direct leaf counts in the understorey of a wet evergreen forest in southern India. The point quadrat method has a tendency to overestimate, whereas the photographic method consistently and significantly underestimates foliage density. There was stratification within the understorey, with areas close to the ground having higher foliage densities
Do endemic rattans have lower Genetic variability than their Co-generic and con-specific non-endemic rattans?
No full textComparisons between the population genetic variability of endemic and non-endemic species provide valuable information for the conservation of the endemic species. Comparisons between the endemic and non-endemic species are seldom carried out with con-generic and co-occurring species. In this study, we have compared three pairs of con-specific endemic and non-endemic rattan species at three locations in the Central Western Ghats, one of the global biodiversity hot-spots located in India. We have analyzed the demographic structure of these species across these three sites. We found that overall the endemic rattan species suffered from poor regeneration compared to their con-specific and con-generic non endemic rattan species. We also used molecular markers to analyze the genetic variability of these endemic and non-endemic rattan species. Our results suggest that, except in one species, the genetic variability of the endemic species was significantly lower than the con-specific non-endemic rattan species. These results indicate the lower genetic variability of the endemic species and have important implications in prioritizing species for conservatio
Functional dioecy in Nothapodytes nimmoniana, a distylous species in the Western Ghats
No full textNothapodytes nimmoniana (Icacinaceae) is a subcanopy
tree species, commercially exploited for its
wood chips that yield an anti-tumour alkaloid. The
species displays intriguing sexual variation. Apart
from the flowers which are comparable to typical
thrum and pin morphs of distylous species, some flowers
show intermediate features. We studied functional
gender of the different flower types to assess the sexuality
of individual plants in two populations in the
Biligiri Rangan Hills Wildlife Sanctuary, Western
Ghats, India. The species shows functional/cryptic
dioecy. Thrum flowers are functionally males, pin
flowers are females and intermediate flowers are
bisexual with functional pollen and stigma. Apart
from male and female plants, a small proportion of
plants which are essentially males produces a small
number of female and bisexual flowers. We refer to
the sexual system in Nothapodytes as subdioecy and it
appears to be a transitory stage in the evolution of
dioecy from heterostyly
Attenuation of camptothecin production and negative relation between hyphal biomass and camptothecin content in endophytic fungal strains isolated from Nothapodytes nimmoniana Grahm (Icacinaceae)
Get PDFEndophytic fungi, a group of fungi living inside the host plant tissues without causing visible symptoms of disease, are known to occur ubiquitously in plants. Existing in a mutualistic association with their host plants, they have been shown to enhance the plant’s ability to tolerate abiotic and biotic stresses3. In culture, many endophytic species have been shown to produce a number of important secondary metabolites including anticancer,antidiabetic, antifungal and immunosuppressant compounds. Many of these compounds closely mimic those produced by the respective host plants, suggesting that the fungi could in fact potentially serve as an alternative source of plant secondary metabolites. Notwithstanding these findings, to date, there has been no major breakthrough in commercially exploiting the endophytic fungi as a source of important secondary metabolites. Among the reasons attributed is the severe attenuation of production of the secondary metabolite by the fungi in culture. Li et al. showed that successive cultures of an endophytic fungi Pericornia sp. isolated from Torreya grandifolia, resulted in the attenuation of taxol production, though the fungal growth itself was unaffected. Although the reasons for such attenuation are not extensively studied, it is conjectured that it could be due to lack of host stimulus in the culture media