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Reshaping Urban Green Spaces
No full textUrban biodiversity and the associated ecosystem services have been ignored and undervalued because ecologists have focused only on pristine habitats and rare species.However, with rapid urbanisation the challenge is to build the native biodiversity within the urban landscape. This could be done by involving multiple stakeholders like the local municipality, architects and, most importantly, citizens in the neighbourhood. We also need to follow the concept of adaptive co-management
How promising are endophytic fungi as alternative sources of plant secondary metabolites?
Get PDFIn this article the authors discusses the use of endophytic fungi as substitute of plant secondary metabolites. It states that endophytic fungi exist internally in plants and enhance the plants' ability to tolerate abiotic and biotic stresses. Endophytic fungi if cultured outside their host can produce secondary metabolites such as anti-cancer, anti-fungal, anti-diabetic and immunosuppressant compounds
Spectral Distance Decay: Assessing Species Beta-diversity by Quantile Regression
No full textRemotely sensed data represents key information for characterizing and estimating biodiversity. Spectral distance among sites has proven to be a powerful approach for detecting species composition variability. Regression analysis of species similarity versus spectral distance may allow us to quantitatively estimate how beta diversity in species changes with respect to spectral and ecological variability. In classical regression analysis, the residual sum of squares is minimized for the mean of the dependent variable distribution. However, many ecological datasets are characterized by a high number of zeroes that can add noise to the regression model. Quantile regression can be used to evaluate trend in the upper quantiles rather than a mean trend across the whole distribution of the dependent variable. In this paper, we used ordinary least square (OLS) and quantile regression to estimate the decay of species similarity versus spectral distance. The achieved decay rates were statistically nonzero (p � 0.05) considering both OLS
and quantile regression. Nonetheless, OLS regression estimate of mean decay rate was only half the decay rate indicated by the upper quantiles. Moreover, the intercept value, representing the similarity reached when spectral distance approaches zero, was very low compared with the intercepts of upper quantiles, which detected high species similarity when habitats are more similar. In this paper we demonstrated the power of using quantile regressions applied to spectral distance decay in order
to reveal species diversity patterns otherwise lost or underestimated by ordinary least square regression
Broadening the Genetic Base of Crop Brassicas by Production of New Intergeneric Hybrid
No full textWide hybridization between crop brassicas and their wild relatives is an important approach towards increasing the genetic variability, which can be utilised for brassica breeding programs. A new intergeneric hybrid between Erucastrum cardaminoides and Brassica oleracea var. alboglabra was produced using embryo rescue techniques.The F1 hybrid was intermediate between the male and female parent for most of the morphological
characters. Cytological studies of pollen mother cells of the hybrid revealed a preponderance of univalents at
metaphase I. The number of bivalents in the digenomic hybrid was lower than expected. However, the presence
of trivalent and quadrivalent in cells indicated some homoeology between the two genomes and hence the possibility of introgression of genes into the cultivar. The first backcross progeny was obtained using B.oleracea
var. alboglabra as the pollen parent. Further, it is being used for developing new alloplasmic lines.The intergeneric hybrid was also used as bridge species to transfer wild (E. cardaminoides) cytoplasm to B. napus and B. carinata. The new intergeneric hybrid and bridge cross hybrids produced in the present investigation have
contributed towards increasing the genic and cytoplasmic variability and thus broadening the genetic base of
crop brassicas
People’s Perception of Benefits from a Protected Catchment: A Case Study of Gundal Command in Karnataka
No full textThis study was conducted in the command area of the Gundal irrigation project in Karnataka which is dependent on a forested catchment. It estimated the direct benefits and assessed the perceived indirect benefits of the protected watershed accruing to the community of the command area. Quantifying the major direct benefits (crops and fodder) realized by 4% of the beneficiary population, the study arrived at an estimated lower-bound (as some direct and all indirect benefits are not quantified) annual benefit of more than Rs.4 crores for 3584 acres of the command area. This indicates an additional amount of Rs.8667 per acre compared to un-irrigated farms in the area
Competing Visions: Domestic Forests, Politics and Forest Policy in the Central Western Ghats of South India
No full textRural people in developing countries including India continue to access a number of types of ‘forests’ to meet specific needs such as fuelwood, fodder, food, non-timber forest produce and timber for both subsistence and income generation. While a plethora of terms exist to describe the types of forests that rural people use—such as farm forests, social forests, community forests and small-scale forests—the expression domestic forest has recently been proposed. Domestic forest is a term aimed at capturing the diversity of forests transformed and managed by rural communities and a way to introduce a new scientific domain that recognises that production and conservation can be reconciled and that local communities can be effective managers. This paper argues in the context of the central Western Ghats of south India that while the domestic forest concept is a useful umbrella term to capture the diversity of forests used by rural people, these domestic forests are often not autonomous local forests but sites of contestation between local actors and the state forest bureaucracy. Hence, a paradigm shift within the forest bureaucracy will only occur if the scientific forestry community questions its own normative view
Protected on paper, hunted in wetlands: exploitation and trade of freshwater turtles (Melanochelys trijuga coronata and Lissemys punctata punctata) in Punnamada, Kerala, India
No full textSoft shell turtles are among the most threatened groups of freshwater animals that are in need of urgent conservation attention. In Kerala (South India), two species of freshwater turtles, the Indian black turtle or Indian pond terrapin, Melanochelys trijuga coronata (Schweigger, 1812) and the Indian Flap-shelled turtle Lissemys punctata punctata (Lacépède, 1788) are exploited from Vembanad lake and associated wetlands in Punnamada to meet the demand from local restaurants and toddy shops. Eight hundred and forty three individuals belonging to the two species (499 pond terrapins and 344 flap-shelled turtle) were observed during a field survey conducted in 2007 at Punnamada. Despite being listed at the highest level in the Indian wildlife protection act, very little law enforcement takes place and turtles are exploited and traded regularly. Collection and trade have also become an important component of the local livelihoods in Punnamada, with the involvement of around five full-time and 25 part-time collectors. Details of the collection, marketing, economics and management of the freshwater turtles in Punnamada are discussed
Prospecting for alternate sources of shikimic acid, a precursor of Tamiflu, a bird-flu drug
Get PDFShikimic acid, more commonly known by its anionic form, shikimate, is an important intermediate compound of the
‘shikimate pathway’ in plants and microorganisms1. It is the principal precursor for the synthesis of aromatic amino acids,phenylalanine, tryptophan and tyrosine and other compounds such as alkaloids, phenolics and phenyl propanoids2. It is used extensively as a chiral building
block for the synthesis of a number of compounds in both pharmaceutical and cosmetic industries3. In the recent past, the focus on shikimic acid has increased since it is the key precursor for the synthesis of Tamiflu, the only drug against avian flu caused by the H5N1 virus4,5.
Shikimic acid is converted to a diethyl ketal intermediate, which is then reduced in two steps to an epoxide that is finally transformed to Tamiflu6
Landscapes of Protection: Forest Change and Fragmentation in Northern West Bengal, India
No full textIn the tropics and sub-tropics, where high levels of biodiversity co-exist with some of the greatest levels
of population density, achieving complete exclusion in
protected area contexts has proved close to impossible.
There is a clear need to recognize that parks are significantly impacted by human–environment interactions in the larger landscape within which they are embedded, and to move the frontier of research beyond the boundaries of protected areas in order to examine larger landscapes where multiple forms of ownership and access are embedded. This research evaluates forest change and
fragmentation between 1990 and 2000, in a landscape
surrounding the Mahananda Wildlife Sanctuary in the
Indian state of West Bengal. This protected forest is
bounded to the south by a less intensively protected area, the Baikunthapur Reserve Forest, and surrounded by a mosaic of unprotected, largely private land holdings.
Results indicate differences in the extent and spatial pattern of forest cover change in these three zones, corresponding to different levels of government protection, access and monitoring. The two protected areas experience a trend toward forest regrowth, relating to the cessation of commercial logging by park management during this period
Watershed services of tropical forests: from hydrology to economic valuation to integrated analysis
No full text‘Watershed services’ provided by forest ecosystems are
receiving increasing attention in the research and policy arena. Changes in forest cover in tropical regions take many different forms and result in multi-dimensional changes in watershed processes: soil erosion rates, peak and low-flow levels, groundwater recharge rates, and water quality. These changes are in turn mediated by the socio-technical context to create a variety of context-specific human impacts, which constitute watershed ‘services’ (or ‘dis-services’). Over the past decade, understanding of the biophysical linkage has generally become nuanced. But large gaps remain in regions like south Asia and Africa and on the question of how different types of forest transitions affect low flows, and the sociohydrological links are inadequately studied. Economic valuation studies are still plagued with conceptual errors, oversimplified biophysical models, lack of social and technological context, and focus on lump-sum numbers. Greater integration of concepts, methods and latest results, and attention to context-specificity, are required for generating policy-relevant insights