Anupam Ghosh

Bio: Anupam Ghosh is an academic researcher from Bankura Christian College. The author has contributed to research in topics: Culex quinquefasciatus & Anopheles stephensi. The author has an hindex of 21, co-authored 51 publications receiving 2368 citations. Previous affiliations of Anupam Ghosh include University of Burdwan.

Ecosystems and Human Well-Being

Abstract: Over the past 50 years, humans have altered their environment to a significant extent, although human well-being is dependent on ecosystem functioning. Ecosystems are particularly affected by unsustainable use of resources, such as, food, water, and timber. Ecosystem functions depend on water, carbon, and other nutrients cycles. Human activities have modified these cycles in a number of way. Use of ecosystems for recreation, spiritual enrichment, cultural purposes, and for other short term benefits is growing continuously, although ecosystem capacity to provide such services has reported to be declined significantly. Human well-being depends on material welfare, health, good social relations, security and freedom, which are affected by changes in ecosystem services. Intensive ecosystem use often produces short-term advantage. Poverty level remains high in more than one billion people, who are dependent on ecosystems with an income of less than $1 per day as reported elsewhere. Regions including some parts of Africa, Asia and Latin America have the greatest ecosystemrelated problems and are facing developmental challenges. Habitat change occurs, for instance, when the area of land used for agriculture or cities is expanded. Instability and unproductivity including desertification, water logging, mineralization and many other unwanted outcomes throughout the world are continuing. Habitat fragmentation by roads, canals, power lines limits the species potential for dispersal and colonization. Indirect drivers, like changes in human population, economic activity and technology as well as socio-political and cultural factors affect ecosystems by influencing direct drivers. World climate has changed and continues to change, affecting temperature, rainfall and sea levels. Intensive fertilizer use has polluted ecosystems. Climate change and high nutrient levels in water are becoming increasing problems. Ecosystem management for shortterm benefits is increasing. Loss of biodiversity makes it difficult for ecosystems to recover from damage. Once an ecosystem has undergone an abrupt change, recovery to the original state is slow, costly, and sometimes impossible. Changes in ecosystems complexity- functioning relationships could diminish the stability, resistance and resilience of managed terrestrial ecosystems, and may jeopardize important food and fibre sources, and ability of natural ecosystems both to provide natural resources, and to remove pollutants from atmosphere. Ecological complexity and ecosystem functioning depend on factors that govern species coexistence. Complexity of landscapes is determined by number of ecosystem types, their characteristics, their sizes and shapes, and associated connectivity. Complexity at this scale would have large consequences on regional to global scale processes. Presence and arrangement of keystone ecosystem types, such as, wetlands often determine total carbon and nitrogen balance of a region. Changes in average or extreme environmental events and intense land use management are believed to increase species extinction rate in isolated habitat fragments. Loss of key species, such as, top predators, fruit dispersers and pollinators from habitat may severely disrupt ecosystems functioning. Land use changes due to expanding urbanization, concomitant landscape fragmentation and intensification of production systems. Such change results in transformation of an ecosystem, form one state to another state, via a transition phase. The combined value of 17 ecosystem services has been reported in the estimated range of US$16-54 trillion per year by Costanza and others. About 30% of modern medicines are developed from plants and animals, and 10 of the world's 25 topselling drugs in 1997 were reported to be derived from natural sources. Global market value of pharmaceuticals derived from genetic resources is estimated at US $ 75 000-150 000 million annually. Some 75% of the world's populations rely for health care on traditional medicines, which are derived directly from natural sources as recorded elsewhere. Socio-economic development of human civilization and human well-being depends on long-term health of environment including ecosystems. Environmental problems are generally addressed in isolation, but practically such problems are interrelated, and originate from the root cause of unsustainable development. Damage to natural ecosystems and release of environmental pollutants must be minimized for protecting natural ecosystem, and human well-being.

Plant extracts as potential mosquito larvicides

Abstract: Mosquitoes act as a vector for most of the life threatening diseases like malaria, yellow fever, dengue fever, chikungunya ferver, filariasis, encephalitis, West Nile Virus infection, etc. Under the Integrated Mosquito Management (IMM), emphasis was given on the application of alternative strategies in mosquito control. The continuous application of synthetic insecticides causes development of resistance in vector species, biological magnification of toxic substances through the food chain and adverse effects on environmental quality and non target organisms including human health. Application of active toxic agents from plant extracts as an alternative mosquito control strategy was available from ancient times. These are non-toxic, easily available at affordable prices, biodegradable and show broad-spectrum target-specific activities against different species of vector mosquitoes. In this article, the current state of knowledge on phytochemical sources and mosquitocidal activity, their mechanism of action on target population, variation of their larvicidal activity according to mosquito species, instar specificity, polarity of solvents used during extraction, nature of active ingredient and promising advances made in biological control of mosquitoes by plant derived secondary metabolites have been reviewed.

Mosquito control by larvivorous fish.

Abstract: There is growing of the effects of insecticide used controlling the vectors of human diseases Manipulating or introducing an auto-reproducing predator into the ecosystem may provide sustained biological control of pest populations The selection of a biological agent should be based on its self-replicating capacity, preference for the target pest population in the presence of alternate natural prey, adaptability to the introduced environment, and overall interaction with indigenous organisms In order to achieve an acceptable range of control, a sound knowledge of various attributes of interactions between the pest population and the predator to be introduced is desirable Biological larviciding for the control of mosquito borne diseases is feasible and effective only when breeding sites are relatively few or are easily identified and treated Larval control appears to be promising in urban areas, given that the density of humans needing protection is higher than the limited number of breeding sites Since 1937, fish have been employed for controlling mosquito larvae Different types of fish have been used so far in this operational technique However, use of fish of indigenous origin is found to be more appropriate in this operation This review presents information on different larvivorous fish species and the present status of their use in mosquito control and provides a ready reference for workers involved and interested in mosquito research

Mosquito larvicidal activities of Solanum villosum berry extract against the dengue vector Stegomyia aegypti.

Abstract: Vector control is facing a threat due to the emergence of resistance to synthetic insecticides. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. Although several plants have been reported for mosquitocidal activity, only a few botanicals have moved from the laboratory to field use, because they are poorly characterized, in most cases active principals are not determined and most of the works are restricted to preliminary screening. Solanum villosum is a common weed distributed in many parts of India with medicinal properties, but the larvicidal activity of this plant has not been reported so far. Aqueous and polar/non-polar solvent extract of fresh, mature, green berries of S. villosum was tested against Stegomyia aegypti, a common vector of dengue fever. A phytochemical analysis of chloroform:methanol extract was performed to search for the active toxic ingredient. The lethal concentration was determined (log probit analysis) and compared with Malathion. The chemical nature of the active substance was also evaluated following ultraviolet-visual (UV-Vis) and infrared (IR) analysis. In a 72 hour bioassay experiment with the aqueous extract, the highest mortality was recorded in 0.5% extract. When the mortality of different solvent extracts was compared, the maximum (p < 0.05) mortality was recorded at a concentration of 50 ppm of chloroform:methanol extract (1:1, v/v). The larvicidal activity was lower when compared with the chemical insecticide, Malathion (p < 0.05). Results of regression analysis revealed that the mortality rate (Y) was positively correlated with the period of exposure (X) and the log probit analysis (95% confidence level) recorded lowest value (5.97 ppm) at 72 hours of exposure. Phytochemical analysis of the chlororm:methanol extract reported the presence of many bioactive phytochemicals. Two toxic compounds were detected having R f = 0.82 (70% and 73.33% mortality in 24 and 48 hours, respectively) and R f = 0.95 (40% and 50% mortality in 24 and 48 hours, respectively). IR analysis provided preliminary information about the steroidal nature of the active ingredient. S. villosum offers promise as potential bio control agent against S. aegypti particularly in its markedly larvicidal effect. The extract or isolated bioactive phytochemical could be used in stagnant water bodies for the control of mosquitoes acting as vector for many communicable diseases.

Antibacterial activity of some medicinal plant extracts.

Abstract: Antibacterial activity of hot aqueous and methanolic extracts prepared from six plants (Terminallia chebula, Terminallia bellerica, Phyllanthus emblica, Punica granatum, Lawsonia alba and Mikania micrantha) used in traditional folk medicines of India were screened against five pathogenic bacteria (Staphylococcus aureus MTCC 2940, Bacillus subtilis MTCC 441, Escherichia coli MTCC 739, Proteus vulgaris MTCC 426 and Enterobacter aerogenes MTCC 111). The highest antibacterial potentiality was exhibited by the methanolic leaf extract of T. chebula, followed by the aqueous fruit extract of T. bellerica. The leaf extract of T. chebula can be considered to be as equally potent as the most effective antibiotics, such as ciprofloxacin, gentamycin, kanamycin, ofloxacin and cephalexin. A sensitivity test performed with commonly used sensitivity test disks resulted in the appearance of multiple drug resistance phenotypes of the bacteria tested. A comparision of data in the inhibition zones of pathogenic bacteria showed that gentamycin, ofloxacin, kanamycin and tobramycin were effective against all of the bacterial strains tested.

Scenarios for global biodiversity in the 21st Century

Abstract: Quantitative scenarios are coming of age as a tool for evaluating the impact of future socioeconomic development pathways on biodiversity and ecosystem services. We analyze global terrestrial, freshwater, and marine biodiversity scenarios using a range of measures including extinctions, changes in species abundance, habitat loss, and distribution shifts, as well as comparing model projections to observations. Scenarios consistently indicate that biodiversity will continue to decline over the 21st century. However, the range of projected changes is much broader than most studies suggest, partly because there are major opportunities to intervene through better policies, but also because of large uncertainties in projections.

Biodiversity, Ecosystem Functioning, and Human Wellbeing: An Ecological and Economic Perspective

Abstract: In an age of accelerating biodiversity loss, this timely and critical volume summarizes recent advances in biodiversity-ecosystem functioning research and explores the economics of biodiversity and ecosystem services. The book starts by summarizing the development of the basic science and provides a meta-analysis that quantitatively tests several biodiversity and ecosystem functioning hypotheses. It then describes the natural science foundations of biodiversity and ecosystem functioning research including: quantifying functional diversity, the development of the field into a predictive science, the effects of stability and complexity, methods to quantify mechanisms by which diversity affects functioning, the importance of trophic structure, microbial ecology, and spatial dynamics. Finally, the book takes research on biodiversity and ecosystem functioning further than it has ever gone into the human dimension, describing the most pressing environmental challenges that face humanity and the effects of diversity on: climate change mitigation, restoration of degraded habitats, managed ecosystems, pollination, disease, and biological invasions.However, what makes this volume truly unique are the chapters that consider the economic perspective. These include a synthesis of the economics of ecosystem services and biodiversity, and the options open to policy-makers to address the failure of markets to account for the loss of ecosystem services; an examination of the challenges of valuing ecosystem services and, hence, to understanding the human consequences of decisions that neglect these services; and an examination of the ways in which economists are currently incorporating biodiversity and ecosystem functioning research into decision models for the conservation and management of biodiversity. A final section describes new advances in ecoinformatics that will help transform this field into a globally predictive science, and summarizes the advancements and future directions of the field. The ultimate conclusion is that biodiversity is an essential element of any strategy for sustainable development.

Plant extracts as potential mosquito larvicides

Abstract: Mosquitoes act as a vector for most of the life threatening diseases like malaria, yellow fever, dengue fever, chikungunya ferver, filariasis, encephalitis, West Nile Virus infection, etc. Under the Integrated Mosquito Management (IMM), emphasis was given on the application of alternative strategies in mosquito control. The continuous application of synthetic insecticides causes development of resistance in vector species, biological magnification of toxic substances through the food chain and adverse effects on environmental quality and non target organisms including human health. Application of active toxic agents from plant extracts as an alternative mosquito control strategy was available from ancient times. These are non-toxic, easily available at affordable prices, biodegradable and show broad-spectrum target-specific activities against different species of vector mosquitoes. In this article, the current state of knowledge on phytochemical sources and mosquitocidal activity, their mechanism of action on target population, variation of their larvicidal activity according to mosquito species, instar specificity, polarity of solvents used during extraction, nature of active ingredient and promising advances made in biological control of mosquitoes by plant derived secondary metabolites have been reviewed.

Research in mosquito control: current challenges for a brighter future.

Abstract: Mosquitoes (Diptera: Culicidae) are a key threat for millions of people worldwide, since they act as vectors for devastating pathogens and parasites. In this scenario, vector control is crucial. Mosquito larvae are usually targeted using organophosphates, insect growth regulators, and microbial agents. Indoor residual spraying and insecticide-treated bed nets are also employed. However, these chemicals have negative effects on human health and the environment and induce resistance in a number of vectors. Newer and safer tools have been recently implemented to enhance control of mosquitoes. Here, I focus on some crucial challenges about eco-friendly control of mosquito vectors, mainly the improvement of behavior-based control strategies (sterile insect technique (“SIT”) and “boosted SIT”) and plant-borne mosquitocidals, including green-synthesized nanoparticles. A number of hot areas that need further research and cooperation among parasitologists, entomologists, and behavioral ecologists are highlighted.