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71.
Tourism and wetland conservation: application of travel cost and willingness to pay an entry fee at Ghodaghodi Lake Complex,Nepal
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Pramod Lamsal Kishor Atreya Krishna Prasad Pant Lalit Kumar 《Natural resources forum》2016,40(1-2):51-61
This study investigated the need and applicability of wetland tourism for resource conservation, using the case of Ghodaghodi Lake Complex, a Ramsar Site in western Nepal. The travel cost method (TCM) was used to determine the recreation potential of the lake complex, while the contingent valuation method (CVM) was used to calculate willingness of visitors to pay an entry fee as a payment vehicle for conservation. The per capita travel cost was found to be NPR 540 (US $7.71), while the mean willingness to pay an entry fee was NPR 34 (US $0.48) per visitor per entry. In addition, factors affecting wetland visitation rates and maximum willingness to pay were identified. Policy implications include the establishment of an entry fee system to offset conservation budgetary constraints, government investment in social benefits equating to at least per capita travel cost identified, and public‐private partnerships, with community participation in tourism promotion and wetland conservation. 相似文献
72.
Bibhash C. Verma Siba Prasad Datta Raj K. Rattan Anil K. Singh 《Environmental monitoring and assessment》2010,171(1-4):579-593
Soil organic matter not only affects sustainability of agricultural ecosystems, but also extremely important in maintaining overall quality of environment as soil contains a significant part of global carbon stock. Hence, we attempted to assess the influence of different tillage and nutrient management practices on various stabilized and active soil organic carbon pools, and their contribution to the extractable nitrogen phosphorus and sulfur. Our study confined to the assessment of impact of agricultural management practices on the soil organic carbon pools and extractable nutrients under three important cropping systems, viz. soybean–wheat, maize–wheat, and rice–wheat. Results indicated that there was marginal improvement in Walkley and Black content in soil under integrated and organic nutrient management treatments in soybean–wheat, maize–wheat, and rice–wheat after completion of four cropping cycles. Improvement in stabilized pools of soil organic carbon (SOC) was not proportional to the applied amount of organic manures. While, labile pools of SOC were increased with the increase in amount of added manures. Apparently, green manure (Sesbania) was more effective in enhancing the lability of SOC as compared to farmyard manure and crop residues. The KMnO4-oxidizable SOC proved to be more sensitive and consistent as an index of labile pool of SOC compared to microbial biomass carbon. Under different cropping sequences, labile fractions of soil organic carbon exerted consistent positive effect on the extractable nitrogen, phosphorus, and sulfur in soil. 相似文献
73.
Seasonal variation in physicochemical properties of coastal waters of Kalpakkam, east coast of India with special emphasis on nutrients 总被引:1,自引:0,他引:1
K. K. Satpathy A. K. Mohanty U. Natesan M. V. R. Prasad S. K. Sarkar 《Environmental monitoring and assessment》2010,164(1-4):153-171
A study pertaining to the seasonal variation in physicochemical properties of the coastal waters was carried out at Kalpakkam coast for a period of 1 year (February 2006 to January 2007). It revealed that the coastal water was significantly influenced by freshwater input during North East (NE) monsoon and post-monsoon periods. Concentration of all the nutrients and dissolved oxygen (DO) was relatively high during the NE monsoon, whereas, salinity and chlorophyll-a (chl-a) were at their minimum level during this period. Phytoplankton production peak was observed in summer during which a typical marine condition prevailed. The present observed values of nitrate, phosphate, silicate, and turbidity are significantly high (five to ten times) compared to that of the pre-Tsunami period from this coast. Relatively low DO and chl-a concentration was noticed during the post-Tsunami period. A notable feature of this study is that though nutrient concentration in the coastal waters during post-Tsunami period has increased significantly, turbidity, the most single dominating factor, was found to adversely affect the phytoplankton production during post-Tsunami period as reflected by relatively low chl-a concentration. Thus, the post-Tsunami period may result in a change in coastal biodiversity pattern concomitant with change in coastal water quality. 相似文献
74.
Theerthagiri Jayaraman Karuppasamy K. Park Juhyeon Rahamathulla Nihila Kumari M. L. Aruna Souza Marciélli K. R. Cardoso Eduardo S. F. Murthy Arun Prasad Maia Gilberto Kim Hyun-Seok Choi Myong Yong 《Environmental Chemistry Letters》2023,21(3):1555-1583
Environmental Chemistry Letters - The decrease in fossil fuel usage and the projected 28% increase in the global energy demand by 2040 are calling for advanced methods to convert modern biomass... 相似文献
75.
A field study made with rice at the Indian Agricultural Research Institute, New Delhi, showed that coating urea with neem
oil, neem cake or neem oil microemulsion improved rice growth and resulted in more grain and straw than did commercial prilled
urea.
Received: 12 April 1999 / Accepted in revised form: 6 August 1999 相似文献
76.
Trace element analysis for five elements namely, Ba, Sr, Mn, Cr and Cd was carried out on both ash weight and dry weight basis for mine water and coconut water from Mangampeta barite area. The concentration of trace elements is strikingly different in the coconut water when compared with that of mine water. The coconut plant has the ability to control the presence of certain inorganic elements in its water, whatever be the amount of those elements present in irrigation water. Further, biogeochemical studies of coconut water may be of considerable importance in balneology. 相似文献
77.
Arunachalam Sivagurulingam Arun Prasad Sivanandi Periyasamy Pandian Sivakumar 《Environmental science and pollution research international》2022,29(5):6646-6655
Environmental Science and Pollution Research - In this study, marine microalgae were isolated from the Bay of Bengal, and their biodiesel production potential was investigated. Five different... 相似文献
78.
R.?Gayathri P.?L.?N.?Murty Prasad?K.?BhaskaranEmail author T.?Srinivasa Kumar 《Environmental Fluid Mechanics》2016,16(2):429-452
The head Bay region bordering the Bay of Bengal is highly vulnerable to tropical cyclones. Catastrophic risks from storm surge and associated inundation are quite high due to high population density in coastal areas, socio-economic conditions, and shallow bathymetry. It features the world’s largest deltaic system comprising of ‘Sunderbans’ bordered by West Bengal and Bangladesh. In a geomorphologic sense, the head Bay region is a low-lying belt comprising several barrier islands and river drainage systems, numerous tidal creeks, and mud flats having a high risk for widespread inundation. In addition, the high tidal range together with low-lying topography leads to high risk and vulnerability from storm surge inundation. During May 2009, a severe cyclonic storm Aila struck West Bengal causing enormous destruction to life and property along coastal belts of West Bengal and Bangladesh. It was the strongest pre-monsoon cyclone in the past two decades that had landfall in West Bengal. This work reports on a numerical study for hypothetical storm surge and associated inundation from Aila using the ADCIRC model. The study covers a comprehensive qualitative analysis on water level elevation and onshore inundation for West Bengal and Bangladesh regions. The estimated peak storm surge was about 4 m in the Sunderban region that propagated into all major riverine systems, inundating the river banks as well the inland areas. Numerical simulations indicate an average inland penetration distance of 350 m with a maximum of 600 m at various coastal locations in West Bengal and Bangladesh. The study emphasizes the need and importance of inundation modeling system required for emergency preparedness and disaster management. 相似文献
79.
Roy BK Prasad R Gunjan 《Journal of environmental biology / Academy of Environmental Biology, India》2010,31(5):567-573
The extent of accumulation of some heavy metals in root and aerial plant parts, total chlorophyll, protein and yield of C. cajan exposed to mine spoil were investigated. Chlorophyll and protein level on the control site increased from the basal level to 1.49 fold and 1.92 fold respectively on 150 d and attained a plateau within 210 d. The maximum decline in leaf protein and yield in selected mine spoil has been observed 37% (18.46 mg g(-1) fresh wt) and 76% at 150 d and maintained a slight decline when duration was extended up to 210 d as compared to control. Whereas in case of photo pigment content (Chlorophyll a and b) the maximum reduction was almost 42% (0.786 mg g(-1) fresh wt) during 210 d from its basal level. Plant tissues have accumulated maximum level of selected cations in control and mine spoil in the order (Fe > Mn > Zn > Cu > Pb > Ni > Cr > Cd). Metal accumulation in different plant parts was observed in the decreasing order roots > shoots > leaves > seeds. Invariably high accumulation of such cations in roots overshoots indicated accumulation, retention or restricted translocation from root to shoot. The metal share of seed varied from 1.3-39.5 fold as compared to their respective controls but their amount was quite below the toxic range. Thus the present work explores the metal accumulation in the plant tissues. 相似文献
80.
N. L. Rodenhouse S. N. Matthews K. P. McFarland J. D. Lambert L. R. Iverson A. Prasad T. S. Sillett R. T. Holmes 《Mitigation and Adaptation Strategies for Global Change》2008,13(5-6):517-540
We used three approaches to assess potential effects of climate change on birds of the Northeast. First, we created distribution and abundance models for common bird species using climate, elevation, and tree species variables and modeled how bird distributions might change as habitats shift. Second, we assessed potential effects on high-elevation birds, especially Bicknell’s thrush (Catharus bicknelli), that may be particularly vulnerable to climate change, by using statistical associations between climate, spruce-fir forest vegetation and bird survey data. Last, we complemented these projections with an assessment of how habitat quality of a migratory songbird, the black-throated blue warbler (Dendroica caerulescens) might be affected by climate change. Large changes in bird communities of the Northeast are likely to result from climate change, and these changes will be most dramatic under a scenario of continued high emissions. Indeed, high-elevation bird species may currently be at the threshold of critical change with as little as 1°C warming reducing suitable habitat by more than half. Species at mid elevations are likely to experience declines in habitat quality that could affect demography. Although not all species will be affected adversely, some of the Northeast’s iconic species, such as common loon and black-capped chickadee, and some of its most abundant species, including several neotropical migrants, are projected to decline significantly in abundance under all climate change scenarios. No clear mitigation strategies are apparent, as shifts in species’ abundances and ranges will occur across all habitat types and for species with widely differing ecologies. 相似文献