ABSTRACT Dengue is known in India since 1940s, but the disease is very limited in its spread. Den... more ABSTRACT Dengue is known in India since 1940s, but the disease is very limited in its spread. Dengue is becoming rampant in many states of southern India. As of now, no specific treatments (therapies) or vaccines are available against the disease. The people of Tamil Nadu and Puducherry, where the dengue incidences are increasing, perceive this spurt as due to poor rainfall and power supply. We attempted to verify this perception. We also sought to find out whether these factors are in concert with the monthly surveillance reports, used to predict yearly dengue cases by formulating a prediction model. The results showed that a combination of rainfall and power supply had major effect on the spread of dengue. The prediction model, incorporating rainfall and power supply data for four seasons, could not predict the dengue outbreaks accurately. Due to poor rainfall and power supply, people resort to storing water when power is available, and this prolonged open storage of water provides habitat for the vector to breed. The present study emphasizes the need to strengthen the surveillance system for timely and effective execution of vector-control programme. It also highlights the need to improve awareness among the public about the vector's ecology. The strategy against such vector-borne diseases has to focus more on environmental health rather than only on disease management that is patient-centred, largely curative and chemical/medicine intensive. GLOBALLY climate change is getting reflected in unusual rainfall pattern leading to surplus rains in some locations, deficient rains elsewhere and untimely burst in rainfall. Studies indicate that the South Indian states are facing perceptible fluctuations in climatic conditions, and possibly the health of people is directly or indirectly affected because of these fluctuations 1,2. Rise in average temperature , an element of climate change, favours higher breeding and spread of the vectors such as Aedes aegypti, and consequently spread of dengue virus 3. In general, incidences of dengue fever, a mosquito-borne tropical disease (Flavivirus, an RNA virus of the family Flaviviridae), are increasing fast resulting in higher morbidity and mortality in humans worldwide, particularly in tropical and subtropical countries 4. More than 2.5 billion people of the global population are at risk and 50–100 million dengue infections per year are likely 5. Earlier in India, although dengue fever was recognized as a classical disease with high morbidity, but no mortality, the disease was mainly restricted to urban and semi-urban areas because of the favourable breeding sites for the vector A. aegypti 6–8. During the past few years, the frequency of dengue hemorrhagic fever (DHF) has increased remarkably in South India 9–11. The density and distribution of the vector depend on a few vital environmental factors such as season, temperature, rainfall and humidity that vary with latitude and altitude 12–14. The life span of the vector is strongly influenced by temperature and humidity and it survives best between 16C and 30C and relative humidity of 60– 80%. The abundance of A. aegypti fluctuates with unusual rainfall pattern and water storage, as it breeds well in the open containers in and around houses 15. Manmade factors such as environmentally negligent developmental activities also cause outbreaks at new locations 16,17. Tamil Nadu gets rains in four spells: winter (January– February), pre-monsoon (March–May), monsoon (June– September) and post-monsoon (October–December). The northeast monsoon, starting in October and lasting up to December, is marked with heavy rainfall, whereas the southwest monsoon, from June to September, accounts for moderate rainfall. Rainfall is scanty in the pre-monsoon period. Of the total annual rainfall (945 mm) in the state, 48% is received during the northeast monsoon, 32% during the southwest monsoon and the rest during other seasons. Rainfall critically influences several crucial issues of people 18. Many towns and cities in Tamil Nadu and Puducherry are dependent on rivers for drinking water and deficit in rainfall reduces drinking water supply. Three consecutive rain-deficit years (2011, 2012 and 2013) and delayed monsoons have created drought-like situations; overall shortfall was 20–23% of the annual average rainfall 19. The reduced rainfall also causes shortfall in power output from hydroelectric projects, and the changes in wind pattern, intensity and speed lead to decline in wind-generated electricity 20. Taking into account the economics of power purchase, there is no choice but drastic compulsory power cuts to counter the power shortage. Because of extended 16-hour daily power cuts in some parts of the state, people are forced to store water in open containers 21,22. An important, but indirect effect of this seems to be proliferation of A. aegypti, the vector spreading dengue. In 2010–2012, outbreaks of dengue/ chikungunya-like…
The ongoing massive global environmental changes and the past learnings have highlighted the urge... more The ongoing massive global environmental changes and the past learnings have highlighted the urgency and importance of further detailed understanding of the earth system and implementation of social ecological sustainability measures in a much more effective and transparent manner. This short communication discuss the potential of sensor webs in addressing those research challenges, highlighting it in the context of air pollution issues.
As a source of biofuels, nutrient scavenger and carbon sequester microalgae (phytoplankton) have ... more As a source of biofuels, nutrient scavenger and carbon sequester microalgae (phytoplankton) have a great potential and hence the inception of this study. The study aims at understanding the growth response of phytoplankton to artificially induced secondary nutrient limitation for efficient utilization of nutrients in biomass production. The growth of phytoplankton was assessed indirectly in terms of optical density measurement and at the end by one-time chlorophyll measurement. Residual nitrate and orthophosphate in the experimental systems was measured at the end by standard methods. It was found that even if the concentrations of nitrogen and phosphorus available are individually sufficient to support a good phytoplankton growth in an aquatic system, a distorted ratio (high deviation from Redfield ratio) between the nutrients created secondary limitation of the nutrient that is at lower level in relation to Redfield ratio. The results also revealed that at lower N: P ratio values with low levels of nutrient concentrations, the growth suffered primary limitation of nutrients. The treatment systems with 7-15 N: P ratio ranges are nutrient efficient and at P concentrations higher than 60 μg/L can be used for economical harvest. These observations can be useful in using wastewater containing P and N in distorted ratios for microalgal biomass production.
The "rice culture" of Kerala is fast vanishing due to the increasing diversion of the l... more The "rice culture" of Kerala is fast vanishing due to the increasing diversion of the land for non-agricultural purposes. The real estate sector is gradually swallowing up the rice cultivating low-lying wetlands. This paper attempts to examine the growth of real estate business and consequent destruction of the wetland ecosystems in the state. W etlands are an important part of the ecosystem and are also the most threatened part of it (Turner 1991). Conserving wetlands as shields against scarcity of water, floods, en-vironmental pollution, and distress of mi-cro-climatic vagaries is therefore impor-tant. Kerala has the largest proportion of land area under wetlands among all the states of India. Compared to other states of the country, wetlands in Kerala are un-der severe anthropogenic threats primari-ly because of high population density and the peculiar distribution of human habita-tions in the state. According to Nair and Sankar (2002), who mapped the wetland systems of...
The various activities being promoted under Mahatma Gandhi National Rural Employment Guarantee Sc... more The various activities being promoted under Mahatma Gandhi National Rural Employment Guarantee Scheme such as water harvesting and soil conservations could have high positive results on environment security and biodiversity and environment conservation. While this article appreciates the integration of biodiversity conservation into the MGNREGS, it points out the importance of preparing panchayat-level biodiversity registers, supporting individual and institutional efforts in biodiversity conservation and the formulation of appropriate policies. M ahatma Gandhi National Rural Employment Guarantee Sch e me (MGNREGS) 1 was launched in 2005. It aims at enhancing the liveli-hood security of people in rural areas by legally guaranteeing at least 100 days of paid employment in every fi nancial year to adult members of any household will-ing to do unskilled manual work related to public work. Covering all the 626 districts of the entire country, benefi ting 41 million households, it is the...
The present study examines the trends in the annual runoff of a tropical river basin Bharathapuzh... more The present study examines the trends in the annual runoff of a tropical river basin Bharathapuzha, a medium sized river in southern India under the influences of anthropogenic pressures and climate change. The examination of the temporal trends in the rainfall, temperature and river runoff was done using historical datasets. It was supplemented with the data on the land use/land cover (LU/LC) change in the basin based on the LANDSAT TM data. By using a multiple regression model, the influential factors determining the river discharge were identified. The results show that while the rainfall influences the runoff positively, new water bodies, dams and other diversions in the fluvial setup in the basin influence the river runoff negatively.
IOP Conference Series: Earth and Environmental Science, 2009
... Page 2. P07.34 Historical analysis of the first rain event and the number of rain days in the... more ... Page 2. P07.34 Historical analysis of the first rain event and the number of rain days in the western part of Palakkad gap, south India Raj Nikhil, PA Azeez Sálim Ali Centre for Ornithology and Natural History (SACON), Coimbatore, India ...
International Journal of Social Ecology and Sustainable Development, 2010
The present study examines responses of the public to a proposed ecotourism program. Several indi... more The present study examines responses of the public to a proposed ecotourism program. Several individuals were randomly contacted in Kerala, India, to elicit their observations and responses to the proposed program, including residents, local travelers and workers. Though a large share of the sample population supported the project, anticipating that it would accelerate the development of the city and increase their annual earnings, many were unaware of the ecological importance of the mangrove wetland. Only 5% of the total sampled populations were aware of the importance of conserving wetland ecosystems in a growing city. This exemplifies the cheerless state of the environmental consciousness of the public in Kerala, despite that the city is among the most literate, socially advanced and environmentally cognizant populations in India. This study highlights the need for development of much deeper scientific consciousness among the public at large.
Anacystis nidulans and Spirulina platensis grown in artificial aqueous culture medium were treate... more Anacystis nidulans and Spirulina platensis grown in artificial aqueous culture medium were treated with Cr as K 2 Cr 2 O 7 and the alteration in growth rate, doubling time, biomass productivity, Chl A content, carbon assimilation and metal uptake were studied. Significant reductions ...
This study reports the toxicity of nickel to Anacystis nidulans and Spirulina platensis grown in ... more This study reports the toxicity of nickel to Anacystis nidulans and Spirulina platensis grown in artificial culture medium and also the accumulation of this metal by these cyanobacteria. The two species were treated with different concentrations of Ni as NiSO 4 5H 2 O. Growth ...
ABSTRACT Dengue is known in India since 1940s, but the disease is very limited in its spread. Den... more ABSTRACT Dengue is known in India since 1940s, but the disease is very limited in its spread. Dengue is becoming rampant in many states of southern India. As of now, no specific treatments (therapies) or vaccines are available against the disease. The people of Tamil Nadu and Puducherry, where the dengue incidences are increasing, perceive this spurt as due to poor rainfall and power supply. We attempted to verify this perception. We also sought to find out whether these factors are in concert with the monthly surveillance reports, used to predict yearly dengue cases by formulating a prediction model. The results showed that a combination of rainfall and power supply had major effect on the spread of dengue. The prediction model, incorporating rainfall and power supply data for four seasons, could not predict the dengue outbreaks accurately. Due to poor rainfall and power supply, people resort to storing water when power is available, and this prolonged open storage of water provides habitat for the vector to breed. The present study emphasizes the need to strengthen the surveillance system for timely and effective execution of vector-control programme. It also highlights the need to improve awareness among the public about the vector's ecology. The strategy against such vector-borne diseases has to focus more on environmental health rather than only on disease management that is patient-centred, largely curative and chemical/medicine intensive. GLOBALLY climate change is getting reflected in unusual rainfall pattern leading to surplus rains in some locations, deficient rains elsewhere and untimely burst in rainfall. Studies indicate that the South Indian states are facing perceptible fluctuations in climatic conditions, and possibly the health of people is directly or indirectly affected because of these fluctuations 1,2. Rise in average temperature , an element of climate change, favours higher breeding and spread of the vectors such as Aedes aegypti, and consequently spread of dengue virus 3. In general, incidences of dengue fever, a mosquito-borne tropical disease (Flavivirus, an RNA virus of the family Flaviviridae), are increasing fast resulting in higher morbidity and mortality in humans worldwide, particularly in tropical and subtropical countries 4. More than 2.5 billion people of the global population are at risk and 50–100 million dengue infections per year are likely 5. Earlier in India, although dengue fever was recognized as a classical disease with high morbidity, but no mortality, the disease was mainly restricted to urban and semi-urban areas because of the favourable breeding sites for the vector A. aegypti 6–8. During the past few years, the frequency of dengue hemorrhagic fever (DHF) has increased remarkably in South India 9–11. The density and distribution of the vector depend on a few vital environmental factors such as season, temperature, rainfall and humidity that vary with latitude and altitude 12–14. The life span of the vector is strongly influenced by temperature and humidity and it survives best between 16C and 30C and relative humidity of 60– 80%. The abundance of A. aegypti fluctuates with unusual rainfall pattern and water storage, as it breeds well in the open containers in and around houses 15. Manmade factors such as environmentally negligent developmental activities also cause outbreaks at new locations 16,17. Tamil Nadu gets rains in four spells: winter (January– February), pre-monsoon (March–May), monsoon (June– September) and post-monsoon (October–December). The northeast monsoon, starting in October and lasting up to December, is marked with heavy rainfall, whereas the southwest monsoon, from June to September, accounts for moderate rainfall. Rainfall is scanty in the pre-monsoon period. Of the total annual rainfall (945 mm) in the state, 48% is received during the northeast monsoon, 32% during the southwest monsoon and the rest during other seasons. Rainfall critically influences several crucial issues of people 18. Many towns and cities in Tamil Nadu and Puducherry are dependent on rivers for drinking water and deficit in rainfall reduces drinking water supply. Three consecutive rain-deficit years (2011, 2012 and 2013) and delayed monsoons have created drought-like situations; overall shortfall was 20–23% of the annual average rainfall 19. The reduced rainfall also causes shortfall in power output from hydroelectric projects, and the changes in wind pattern, intensity and speed lead to decline in wind-generated electricity 20. Taking into account the economics of power purchase, there is no choice but drastic compulsory power cuts to counter the power shortage. Because of extended 16-hour daily power cuts in some parts of the state, people are forced to store water in open containers 21,22. An important, but indirect effect of this seems to be proliferation of A. aegypti, the vector spreading dengue. In 2010–2012, outbreaks of dengue/ chikungunya-like…
The ongoing massive global environmental changes and the past learnings have highlighted the urge... more The ongoing massive global environmental changes and the past learnings have highlighted the urgency and importance of further detailed understanding of the earth system and implementation of social ecological sustainability measures in a much more effective and transparent manner. This short communication discuss the potential of sensor webs in addressing those research challenges, highlighting it in the context of air pollution issues.
As a source of biofuels, nutrient scavenger and carbon sequester microalgae (phytoplankton) have ... more As a source of biofuels, nutrient scavenger and carbon sequester microalgae (phytoplankton) have a great potential and hence the inception of this study. The study aims at understanding the growth response of phytoplankton to artificially induced secondary nutrient limitation for efficient utilization of nutrients in biomass production. The growth of phytoplankton was assessed indirectly in terms of optical density measurement and at the end by one-time chlorophyll measurement. Residual nitrate and orthophosphate in the experimental systems was measured at the end by standard methods. It was found that even if the concentrations of nitrogen and phosphorus available are individually sufficient to support a good phytoplankton growth in an aquatic system, a distorted ratio (high deviation from Redfield ratio) between the nutrients created secondary limitation of the nutrient that is at lower level in relation to Redfield ratio. The results also revealed that at lower N: P ratio values with low levels of nutrient concentrations, the growth suffered primary limitation of nutrients. The treatment systems with 7-15 N: P ratio ranges are nutrient efficient and at P concentrations higher than 60 μg/L can be used for economical harvest. These observations can be useful in using wastewater containing P and N in distorted ratios for microalgal biomass production.
The "rice culture" of Kerala is fast vanishing due to the increasing diversion of the l... more The "rice culture" of Kerala is fast vanishing due to the increasing diversion of the land for non-agricultural purposes. The real estate sector is gradually swallowing up the rice cultivating low-lying wetlands. This paper attempts to examine the growth of real estate business and consequent destruction of the wetland ecosystems in the state. W etlands are an important part of the ecosystem and are also the most threatened part of it (Turner 1991). Conserving wetlands as shields against scarcity of water, floods, en-vironmental pollution, and distress of mi-cro-climatic vagaries is therefore impor-tant. Kerala has the largest proportion of land area under wetlands among all the states of India. Compared to other states of the country, wetlands in Kerala are un-der severe anthropogenic threats primari-ly because of high population density and the peculiar distribution of human habita-tions in the state. According to Nair and Sankar (2002), who mapped the wetland systems of...
The various activities being promoted under Mahatma Gandhi National Rural Employment Guarantee Sc... more The various activities being promoted under Mahatma Gandhi National Rural Employment Guarantee Scheme such as water harvesting and soil conservations could have high positive results on environment security and biodiversity and environment conservation. While this article appreciates the integration of biodiversity conservation into the MGNREGS, it points out the importance of preparing panchayat-level biodiversity registers, supporting individual and institutional efforts in biodiversity conservation and the formulation of appropriate policies. M ahatma Gandhi National Rural Employment Guarantee Sch e me (MGNREGS) 1 was launched in 2005. It aims at enhancing the liveli-hood security of people in rural areas by legally guaranteeing at least 100 days of paid employment in every fi nancial year to adult members of any household will-ing to do unskilled manual work related to public work. Covering all the 626 districts of the entire country, benefi ting 41 million households, it is the...
The present study examines the trends in the annual runoff of a tropical river basin Bharathapuzh... more The present study examines the trends in the annual runoff of a tropical river basin Bharathapuzha, a medium sized river in southern India under the influences of anthropogenic pressures and climate change. The examination of the temporal trends in the rainfall, temperature and river runoff was done using historical datasets. It was supplemented with the data on the land use/land cover (LU/LC) change in the basin based on the LANDSAT TM data. By using a multiple regression model, the influential factors determining the river discharge were identified. The results show that while the rainfall influences the runoff positively, new water bodies, dams and other diversions in the fluvial setup in the basin influence the river runoff negatively.
IOP Conference Series: Earth and Environmental Science, 2009
... Page 2. P07.34 Historical analysis of the first rain event and the number of rain days in the... more ... Page 2. P07.34 Historical analysis of the first rain event and the number of rain days in the western part of Palakkad gap, south India Raj Nikhil, PA Azeez Sálim Ali Centre for Ornithology and Natural History (SACON), Coimbatore, India ...
International Journal of Social Ecology and Sustainable Development, 2010
The present study examines responses of the public to a proposed ecotourism program. Several indi... more The present study examines responses of the public to a proposed ecotourism program. Several individuals were randomly contacted in Kerala, India, to elicit their observations and responses to the proposed program, including residents, local travelers and workers. Though a large share of the sample population supported the project, anticipating that it would accelerate the development of the city and increase their annual earnings, many were unaware of the ecological importance of the mangrove wetland. Only 5% of the total sampled populations were aware of the importance of conserving wetland ecosystems in a growing city. This exemplifies the cheerless state of the environmental consciousness of the public in Kerala, despite that the city is among the most literate, socially advanced and environmentally cognizant populations in India. This study highlights the need for development of much deeper scientific consciousness among the public at large.
Anacystis nidulans and Spirulina platensis grown in artificial aqueous culture medium were treate... more Anacystis nidulans and Spirulina platensis grown in artificial aqueous culture medium were treated with Cr as K 2 Cr 2 O 7 and the alteration in growth rate, doubling time, biomass productivity, Chl A content, carbon assimilation and metal uptake were studied. Significant reductions ...
This study reports the toxicity of nickel to Anacystis nidulans and Spirulina platensis grown in ... more This study reports the toxicity of nickel to Anacystis nidulans and Spirulina platensis grown in artificial culture medium and also the accumulation of this metal by these cyanobacteria. The two species were treated with different concentrations of Ni as NiSO 4 5H 2 O. Growth ...
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