The Experts below are selected from a list of 2928 Experts worldwide ranked by ideXlab platform
Raphael B B Mwalyosi - One of the best experts on this subject based on the ideXlab platform.
-
Land-use Changes and Resource Degradation in South–West Masailand, Tanzania
Environmental Conservation, 1992Co-Authors: Raphael B B MwalyosiAbstract:This study uses sequential aerial photography to identify environmental changes. The interpreted aerial photos constitute a data-bank of past and present land cover/uses.* Substantial changes have been observed in the areas of cultivation, woody cover, and bare ground.An increased 449.9% of the surveyed area has been cleared for cultivation during the last 30 years, while 77.2% of the former woodland has been destroyed during the same period, contributing to a 15.6% increase in grassland. Bare ground increased by 33.1%. Increased cultivation is caused by increase in the population of subsistence farmers and mechanization. Expansion of cultivation and overexploitation of woody Resources (fuel-wood and building materials) are the causes of decline in the woody vegetation. As consumption of woody Resources exceeds natural regeneration, woody cover is gradually replaced by grasslands.Diminution of the woody vegetation results in shortage of fuel-wood and building materials and consequent misery to the local people. Expansion of cultivation reduces grazing-land, leading to overstocking and overgrazing. Extensive cultivation, based on soil ‘mining’, subjects more and more land to physical and chemical soil Degradation, leading in turn to decline in soil fertility and crop yields. Both overgrazing and extensive cultivation accelerate soil erosion in the area, reducing available cropland, while siltation and flooding cause serious damage to property and infrastructure.Lack of effective land-use planning, uncontrolled population growth, and introduction of the Tanzanian village agricultural production system in a semi-arid area, have contributed to the present deplorable state of affairs. In general, the area shows increasing environmental Degradation and Resource depletion, while very little conservation effort is being made to reverse the trend. These results indicate that a sustainable Resource management plan is urgently needed for the area.
-
land use changes and Resource Degradation in south west masailand tanzania
Environmental Conservation, 1992Co-Authors: Raphael B B MwalyosiAbstract:This study uses sequential aerial photography to identify environmental changes. The interpreted aerial photos constitute a data-bank of past and present land cover/uses.* Substantial changes have been observed in the areas of cultivation, woody cover, and bare ground. An increased 449.9% of the surveyed area has been cleared for cultivation during the last 30 years, while 77.2% of the former woodland has been destroyed during the same period, contributing to a 15.6% increase in grassland. Bare ground increased by 33.1%. Increased cultivation is caused by increase in the population of subsistence farmers and mechanization. Expansion of cultivation and overexploitation of woody Resources (fuel-wood and building materials) are the causes of decline in the woody vegetation. As consumption of woody Resources exceeds natural regeneration, woody cover is gradually replaced by grasslands. Diminution of the woody vegetation results in shortage of fuel-wood and building materials and consequent misery to the local people. Expansion of cultivation reduces grazing-land, leading to overstocking and overgrazing. Extensive cultivation, based on soil ‘mining’, subjects more and more land to physical and chemical soil Degradation, leading in turn to decline in soil fertility and crop yields. Both overgrazing and extensive cultivation accelerate soil erosion in the area, reducing available cropland, while siltation and flooding cause serious damage to property and infrastructure. Lack of effective land-use planning, uncontrolled population growth, and introduction of the Tanzanian village agricultural production system in a semi-arid area, have contributed to the present deplorable state of affairs. In general, the area shows increasing environmental Degradation and Resource depletion, while very little conservation effort is being made to reverse the trend. These results indicate that a sustainable Resource management plan is urgently needed for the area.
Paolo Squarci - One of the best experts on this subject based on the ideXlab platform.
-
groundwater Resource Degradation in coastal plains the example of the cecina area tuscany central italy
Applied Geochemistry, 2007Co-Authors: Sergio Grassi, Gianni Cortecci, Paolo SquarciAbstract:Abstract The paper describes the Degradation of the groundwater Resources in the Cecina area, where seawater intrusion, B contamination and NO 3 pollution are all affecting the heavily exploited Pleistocene aquifer. Over-pumping has brought water levels to about 0 m.a.s.l. as far as about 7 km from the shore line, thereby promoting the seawater intrusion. The intrusion, which is characterized by cation exchange phenomena and Ca–Cl type waters, enters the plain mostly through the shallower horizons. The saline front, which advanced from 0.5 to 1 km in 4 a, has by now reached the foot of the hills to the east of the town, where it is also affecting wells of the local aqueduct. Boron contamination, linked to past discharge of industrial waste transported downstream by the river, reached concentrations as high as 3.5 mg/L in the mid-1980s. Although a decreasing trend is now under way, B content is still close to 1 mg/L. The presence of high NO 3 , which, together with the seawater intrusion, represents a major issue for groundwater management in the area, is linked to the widespread utilization of fertilizers. Nitrate concentration, which reaches a maximum of about 300 mg/L in the shallow aquifer horizons and then decreases rather regularly with depth, is strongly influenced by precipitation. However, irrigation also contributes significantly to transporting the NO 3 contamination to depth, as clearly shown by δ 18 O data. The severe decline in the quality of the groundwater Resource in the Cecina area is further compounded by an overall decrease in water availability in the region of Tuscany, as evidenced by long-term monitoring of precipitation and fluvial discharge.
-
Groundwater Resource Degradation in coastal plains: The example of the Cecina area (Tuscany – Central Italy)
Applied Geochemistry, 2007Co-Authors: Sergio Grassi, Gianni Cortecci, Paolo SquarciAbstract:Abstract The paper describes the Degradation of the groundwater Resources in the Cecina area, where seawater intrusion, B contamination and NO3 pollution are all affecting the heavily exploited Pleistocene aquifer. Over-pumping has brought water levels to about 0 m.a.s.l. as far as about 7 km from the shore line, thereby promoting the seawater intrusion. The intrusion, which is characterized by cation exchange phenomena and Ca–Cl type waters, enters the plain mostly through the shallower horizons. The saline front, which advanced from 0.5 to 1 km in 4 a, has by now reached the foot of the hills to the east of the town, where it is also affecting wells of the local aqueduct. Boron contamination, linked to past discharge of industrial waste transported downstream by the river, reached concentrations as high as 3.5 mg/L in the mid-1980s. Although a decreasing trend is now under way, B content is still close to 1 mg/L. The presence of high NO3, which, together with the seawater intrusion, represents a major issue for groundwater management in the area, is linked to the widespread utilization of fertilizers. Nitrate concentration, which reaches a maximum of about 300 mg/L in the shallow aquifer horizons and then decreases rather regularly with depth, is strongly influenced by precipitation. However, irrigation also contributes significantly to transporting the NO3 contamination to depth, as clearly shown by δ18O data. The severe decline in the quality of the groundwater Resource in the Cecina area is further compounded by an overall decrease in water availability in the region of Tuscany, as evidenced by long-term monitoring of precipitation and fluvial discharge.
Edward B Barbier - One of the best experts on this subject based on the ideXlab platform.
-
Poverty, development, and environment
Environment and Development Economics, 2010Co-Authors: Edward B BarbierAbstract:This paper examines the complex relationship that exists between poverty and natural Resource Degradation in developing countries. The rural poor are often concentrated in fragile, or less favorable, environmental areas. Consequently, their livelihoods can be intimately dependent on natural Resource use and ecosystem services. The relationship between poverty and natural Resource Degradation may depend on a complex range of choices and tradeoffs available to the poor, which in the absence of capital, labor, and land markets, is affected by their access to outside employment and any natural Resource endowments. The paper develops a poverty-environment model to characterize some of these linkages, and concludes by discussing policy implications and avenues for further research.
-
DEFORESTATION, LAND Degradation AND RURAL POVERTY IN LATIN AMERICA: EXAMINING THE EVIDENCE
Environmental Economics and Policy Making in Developing Countries, 2009Co-Authors: Edward B BarbierAbstract:The following paper examines aggregate evidence of a link between rural poverty, land Degradation and deforestation in Latin America. Overall trends in land Degradation and deforestation are discussed, as well as the geographical ‘location’ of the rural poor. The paper also compares and contrasts three statistical analyses of the factors influencing deforestation across the region, and finds evidence of potential rural poverty-Resource Degradation linkages given the negative relationship between income per capita as well as agricultural yields and deforestation, as well as the positive relationship between rural population density and forest clearance. However, policies aimed at increasing economic growth are not sufficient on their own to reverse the rural poverty-Resource Degradation linkage in Latin America. Instead, these need to be supported by more targeted policies and investments to raise the comparative returns to existing agricultural lands, improve the access of poor rural households to land and credit markets, extend key infrastructure, extension and marketing services to the rural poor, and remove tax and pricing distortions that benefit mainly wealthier farmers and landowners.
-
links between economic liberalization and rural Resource Degradation in the developing regions
Agricultural Economics, 2000Co-Authors: Edward B BarbierAbstract:This paper examines evidence of the effects of economic liberalization and globalization on rural Resource Degradation in developing countries. The principal Resource effects of concern are processes of land use change leading to forestland conversion, Degradation and deforestation. The main trends in globalization of interest are trade liberalization and economy-wide reforms in developing countries that have ‘opened up’ the agroindustrial sectors, thus increasing their export-orientation. Such reforms have clearly spurred agroindustrialization, rural development and economic growth, but there is also concern that there may be direct and indirect impacts on rural Resource Degradation. The direct impacts may occur as increased agricultural activity leads to conversion of forests and increased land Degradation from ‘unsustainable’ production methods. However, there may also be indirect effects if agroindustrial development displaces landless, near-landless and rural poor generally, who then migrate to marginal agricultural lands and forest frontier regions. This paper explores these direct and indirect effects of globalization and agroindustrialization on rural Resource Degradation both generally, plus through examining case study evidence. The paper focuses in particular on the examples of structural adjustment, trade liberalization and agricultural development in Ghana, and maize sector liberalization in Mexico under North American Free Trade Agreement (NAFTA).
-
rural poverty and natural Resource Degradation
2000Co-Authors: Edward B BarbierAbstract:The main purpose of this chapter is to investigate the influence of rural poverty on Resource Degradation in Latin America. The main trends in Resource Degradation that will be examined are rural households’ decisions to degrade rather than conserve land Resources, and the expansion of frontier agricultural activity that contributes to deforestation. In addition, the influences of recent policy changes on poverty—environment linkages will be explored.
Sisira Jayasuriya - One of the best experts on this subject based on the ideXlab platform.
-
trade liberalization Resource Degradation and industrial pollution in developing countries
Chapters, 2005Co-Authors: Ian Coxhead, Sisira JayasuriyaAbstract:Trade Theory, Analytical Models and Development, comprises 11 essays offering new contributions on the following topics: trade and wages; factor endowments, factor mobility and political economy of trade; optimality of tariffs; measurement of welfare; customs union theory; endogenous mergers and tariffs; intra-industry trade; state trading enterprises and trade liberalisation; general equilibrium effects of e-Commerce, and trade; economic growth with production and consumption externalities; and environmental pollution and Resource Degradation.
-
trade liberalization Resource Degradation and industrial pollution in developing countries an integrated analysis
Staff Paper Series, 2003Co-Authors: Ian Coxhead, Sisira JayasuriyaAbstract:"Environmental damage" is in reality many different types of phenomena, each with a unique set of causes and characteristics. We present an analytical model identifying intersectoral and interregional links of economy and environment, and explore consequences of trade policy and world price changes. The model contains explicit spatial and institutional features relevant to developing economies. We show that similar trade or policy shocks can have different effects, depending on initial economic structure, trade orientation and policies. Further, when there is more than one sectoral source of environmental damage, a policy or price shock may have unexpected environmental and welfare results.
S Dharmaraja - One of the best experts on this subject based on the ideXlab platform.
-
semi markov modeling of dependability of voip network in the presence of Resource Degradation and security attacks
Reliability Engineering & System Safety, 2011Co-Authors: Vandana A Gupta, S DharmarajaAbstract:Nowadays VoIP has become an evolutionary technology in telecommunications. Hence it is very important to study and enhance its dependability attributes. In this paper, an analytical dependability model for VoIP is proposed. The study is focused on analyzing the combined effects of Resource Degradation and security breaches on the Quality of Service (QoS) of VoIP, to enhance its overall dependability. As a preventive maintenance policy to prevent or postpone software failures which cause Resource Degradation, software rejuvenation is adopted. The dependability model is analyzed using semi-Markov process which captures the effects of non-Markovian nature of the time spent at various states of the system. The steady-state as well as the time-dependent analysis of the dependability model is presented. The steady-state results are obtained analytically, whereas the time-dependent results are obtained from simulation. Also, the analytical model is validated via simulation. The model analysis using a numerical example indicates the feasibility of our approach. Various dependability attributes such as availability, reliability and confidentiality are also obtained. A comparative study is also done between our proposed model and the existing models.
