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1.
Govindasamy?BalaEmail author Ranjith?Gopalakrishnan Mathangi?Jayaraman Ramakrishna?Nemani N.?H.?Ravindranath 《Mitigation and Adaptation Strategies for Global Change》2011,16(2):143-160
There is huge knowledge gap in our understanding of many terrestrial carbon cycle processes. In this paper, we investigate
the bounds on terrestrial carbon uptake over India that arises solely due to CO
2
-fertilization. For this purpose, we use a terrestrial carbon cycle model and consider two extreme scenarios: unlimited CO2-fertilization is allowed for the terrestrial vegetation with CO2 concentration level at 735 ppm in one case, and CO2-fertilization is capped at year 1975 levels for another simulation. Our simulations show that, under equilibrium conditions,
modeled carbon stocks in natural potential vegetation increase by 17 Gt-C with unlimited fertilization for CO2 levels and climate change corresponding to the end of 21st century but they decline by 5.5 Gt-C if fertilization is limited
at 1975 levels of CO2 concentration. The carbon stock changes are dominated by forests. The area covered by natural potential forests increases
by about 36% in the unlimited fertilization case but decreases by 15% in the fertilization-capped case. Thus, the assumption
regarding CO2-fertilization has the potential to alter the sign of terrestrial carbon uptake over India. Our model simulations also imply
that the maximum potential terrestrial sequestration over India, under equilibrium conditions and best case scenario of unlimited
CO2-fertilization, is only 18% of the 21st century SRES A2 scenarios emissions from India. The limited uptake potential of the
natural potential vegetation suggests that reduction of CO2 emissions and afforestation programs should be top priorities. 相似文献
2.
Rajiv K. Chaturvedi Ranjith Gopalakrishnan Mathangi Jayaraman Govindasamy Bala N. V. Joshi Raman Sukumar N. H. Ravindranath 《Mitigation and Adaptation Strategies for Global Change》2011,16(2):119-142
We make an assessment of the impact of projected climate change on forest ecosystems in India. This assessment is based on
climate projections of the Regional Climate Model of the Hadley Centre (HadRM3) and the dynamic global vegetation model IBIS
for A2 and B2 scenarios. According to the model projections, 39% of forest grids are likely to undergo vegetation type change
under the A2 scenario and 34% under the B2 scenario by the end of this century. However, in many forest dominant states such
as Chattisgarh, Karnataka and Andhra Pradesh up to 73%, 67% and 62% of forested grids are projected to undergo change. Net
Primary Productivity (NPP) is projected to increase by 68.8% and 51.2% under the A2 and B2 scenarios, respectively, and soil
organic carbon (SOC) by 37.5% for A2 and 30.2% for B2 scenario. Based on the dynamic global vegetation modeling, we present
a forest vulnerability index for India which is based on the observed datasets of forest density, forest biodiversity as well
as model predicted vegetation type shift estimates for forested grids. The vulnerability index suggests that upper Himalayas,
northern and central parts of Western Ghats and parts of central India are most vulnerable to projected impacts of climate
change, while Northeastern forests are more resilient. Thus our study points to the need for developing and implementing adaptation
strategies to reduce vulnerability of forests to projected climate change. 相似文献
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4.
Budget-Balancing Incentive Mechanisms 总被引:5,自引:0,他引:5
Herriges Joseph A. Govindasamy Ramu Shogren Jason F. 《Journal of Environmental Economics and Management》1994,27(3)
A. P. Xepapadeas [J. Environ. Econom. Management20, 113-26, 1991] developed a pollution abatement incentive mechanism that both reduces the information requirements of a regulator and is "budget-balancing," drawing only on the social gains from pollution abatement to encourage firm compliance. This paper demonstrates that, contrary to Xepapadeas, the budget-balancing system of random penalties cannot be used to induce compliance with the regulator′s objectives if firms are risk neutral. However, the mechanism can be successfully applied if firms are sufficiently risk averse [E. Rasmusen, RAND J. Econom.18, 428-435, 1987]. 相似文献
5.
Venkidasamy Baskar Subramanian Umadevi Samynathan Ramkumar Rajakumar Govindasamy Shariati Mohammad Ali Chung Ill-Min Thiruvengadam Muthu 《Environmental science and pollution research international》2021,28(6):6289-6301
Environmental Science and Pollution Research - Organopesticides (OPs) are a group of various synthetic chemicals prevalently used in agriculture and homestead plantations. OPs were originally... 相似文献
6.
Wildlife Conservation in Taiwan 总被引:3,自引:0,他引:3
7.
Ramu Govindasamy Mark J. Cochran Eta Buchberger 《Journal of the American Water Resources Association》1994,30(5):901-910
ABSTRACT: Non-point source pollution created by agriculture is one of the major issues of intensive production. Recent studies indicate that the eutrophication from agricultural non-point source pollution, especially from phosphorus, is of growing concern. The objectives of this paper are to measure the economic opportunity costs of a proposed phosphorus management policy that targets soils with elevated phosphorus levels and examine the impacts of alternative policies such as Pigouvian taxes on the optimal use of litter. The study focuses on land applications of poultry litter in the Muddy Fork watershed of the Illinois River in Northwest Arkansas. The analysis indicates that restriction of litter applications on soils with elevated phosphorus levels will significantly reduce the net returns generated from forage production, resulting in an environmental policy with a high opportunity cost for producers. An analysis of alternative Pigouvian tax policies shows that a smaller tax per ton of litter applied can achieve the same litter control as that of a larger tax on a per acre basis. 相似文献
8.
9.
Threat of heavy metal pollution in halophytic and mangrove plants of Tamil Nadu, India 总被引:2,自引:0,他引:2
Mangrove and halophytic plants occur along the coastal areas of Tamil Nadu, south India and these plants have been used in traditional medicine for centuries. Heavy metals are known to pose a potential threat to terrestrial and aquatic biota. However, little is known on the toxic levels of heavy metals found in mangrove and halophytic plants that are used in traditional medicine in India. To understand heavy metal toxicity, we investigated the bioconcentration factors (BCF) of heavy metals in leaves collected from eight mangroves and five halophytes in the protected Pichavaram mangrove forest reserve in Tamil Nadu State, south India. Data presented in this paper describe the impact of essential (Cu, Fe, Mg, Mn and Zn) and non-essential/environmentally toxic trace metals (Hg, Pb and Sn) in mangrove and halophytic medicinal plants. The concentrations of Pb among 13 plant species were higher than the normal range of contamination reported for plants. The average concentration of Hg in the halophytic plants (0.43+/-0.37mug/g) was seven times higher than mangrove plants (0.06+/-0.03mug/g) and it indicated pollutants from industrial sources affecting halophytes more than mangroves. 相似文献
10.
Chakraborty C Hsu CH Wen ZH Lin CS Agoramoorthy G 《Journal of environmental biology / Academy of Environmental Biology, India》2011,32(2):179-183
The use of pharmaceuticals during pregnancy may causes abnormalities to the embryo. Sometime the drug also effect to the new born if the drug transferred through lactation. We have used zebrafish model to see the effect of some pharmaceuticals on embryos and larvae. Three drugs, caffeine, norfloxacin and nimesulide, were used for this study to see the effect mainly the hatching rate of eggs, heart beat rate and the vascular endothelial growth factor (VEGF) expression of the larvae. VEGF is an important signaling protein that involved generating the new blood vessels during embryonic development. We have used 10, 20, 50, 100 microg ml(-1) concentrations of all the drugs to see the effect. No significant mortality or malformations were observed in zebrafish embryos. Hatching was stared from 60 hr. In control group, 91% hatching rate was observed. Lowest hatching rate was observed using highest concentration of norfloxacin (100 microg ml(-1)) and nimesulide (100 microg ml(-1)) i.e. 55 and 56% respectively. In control group, 110 to 115 heart beat rate was counted per minute. Significantly higher heart beat was observed in caffeine treated group which is 125 to 140 min(-1) Lower heart beat was noted in nimesulide treated group which is 100 min(-1). We have tried to observe the possible effect of VEGF of the larvae by these three drugs. Expression of VEGF was very low in caffeine treated group. Almost no VGF expression was observe in 100 microg ml(-1) caffeine treated group. These studies suggest that there is a possibility that high dosage of caffeine can harm the unborn baby or new born babies, if the mothers use caffeine. 相似文献