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21.
This paper examines the relationship between economic growth and environmental degradation in Ecuador from 1971 to 2010. We estimate this relationship in a country with a heavy reliance on revenue from the exploitation of natural resources, the depletion of vegetation cover in recent decades and a low level of participation of industry in GDP. We show the existence of an inverse relationship between real GDP and vegetation cover, indicating that the output of this country is based on environmental degradation. Through Johansen co-integration tests, we check that there is a relationship of long-term equilibrium between the first differences of real GDP, vegetal cover and the urbanization rate. The ECM shows that there is a short-term relationship between vegetation cover, the GDP and the rate of urbanization. Finally, we did not found Granger causality between the variables. A policy implication based on our findings is that policies to protect the environment should not jeopardize economic growth and not limit the rapid urbanization in the country.  相似文献   
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This paper presents a study of cement replacement by sugar cane bagasse ash (SCBA) in industrial scale aiming to reduce the CO2 emissions into the atmosphere. SCBA is a by-product of the sugar/ethanol agro-industry abundantly available in some regions of the world and has cementitious properties indicating that it can be used together with cement. Recent comprehensive research developed at the Federal University of Rio de Janeiro/Brazil has demonstrated that SCBA maintains, or even improves, the mechanical and durability properties of cement-based materials such as mortars and concretes. Brazil is the world’s largest sugar cane producer and being a developing country can claim carbon credits. A simulation was carried out to estimate the potential of CO2 emission reductions and the viability to issue certified emission reduction (CER) credits. The simulation was developed within the framework of the methodology established by the United Nations Framework Convention on Climate Change (UNFCCC) for the Clean Development Mechanism (CDM). The State of São Paulo (Brazil) was chosen for this case study because it concentrates about 60% of the national sugar cane and ash production together with an important concentration of cement factories. Since one of the key variables to estimate the CO2 emissions is the average distance between sugar cane/ethanol factories and the cement plants, a genetic algorithm was developed to solve this optimization problem. The results indicated that SCBA blended cement reduces CO2 emissions, which qualifies this product for CDM projects.  相似文献   
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Environmental Science and Pollution Research - Biosolids are a by-product of wastewater treatment, and their nutritional composition makes them ideal for fertilizing crops. However, pre-treatments,...  相似文献   
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ABSTRACT

The concept of reflexive governance has to a large extent emerged from an increasing recognition of the need to consider different meanings of nature in the environmental policy-making process. Yet, so far, little attention has been paid to creating conditions for reflexive governance among different actors in intercultural settings, particularly in the context of environmental conflict and strong cultural change among indigenous peoples. This paper reviews three participatory research projects carried out in the Gran Sabana in Canaima National Park, Venezuela, which facilitated dialogue among indigenous people regarding their conflicting views of fire, in part by developing community-wide critical reflections on processes of cultural change and identity formations. These experiences suggest that once marginalized environmental knowledge is publicly acknowledged within the context of endogenous cultural processes, indigenous people feel more confident to engage in dialogue with other actors, thus allowing the emergence of reflexive environmental governance.  相似文献   
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This contribution determines the coastal erosion risk of Necochea and Quequén cities, Necochea Municipality, Buenos Aires Province (Argentina). Both risk components, hazard and vulnerability, were assessed by the construction of indices. The hazard index is composed of four indicators: the erosion or accretion rate, coastal geomorphology, storm waves effects, and sediment supply. The vulnerability index is comprised of land use/cover, demographic, life conditions, and work and consumption indicators, and includes population census data such as demographic, education, health, sanitary, economic, production, work and population exposure aspects. The analysis concluded that coastal erosion risk ranges from very low to high along the study area, Quequén yielding the highest values. Risk levels vary in both cities based on the uneven spatial distribution of hazard. The risk assessment developed herein constitutes a practical and adequate tool that can be utilized with other elements and tasks in the elaboration of a coastal management program.  相似文献   
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Environment, Development and Sustainability - Current trends such as imminent overpopulation and the take-make-waste economic model are largely responsible for the planet’s dire situation....  相似文献   
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ABSTRACT: Intact riparian zones are the product of an incredibly complex multitude of linkages between the geomorphic, hydrologic, and biotiè features of the ecosystem. Land‐use activities that sever or alter these linkages result in ecosystem degradation. We examined the relationship between riparian vegetation and channel morphology by sampling species composition and herbaceous root biomass in incised (down‐cut and widened) versus unincised (intact) sections of unconstrained reaches in three headwater streams in northeastern Oregon. Incision resulted in a compositional shift from wetland‐obligate plant species to those adapted to drier environments. Root biomass was approximately two times greater in unincised sections than incised sections and decreased with depth more rapidly in incised sections than in unincised sections. Total root biomass ranged from 2,153 g m‐2 to 4,759 g m‐2 in unincised sections and from 1,107 g m‐2 to 2,215 g m‐2 in incised sections. In unincised sections less than 50 percent of the total root biomass was found in the top 10 cm, with approximately 20 percent in successive 10‐cm depth increments. In contrast, incised sections had greater than 60 percent of the total root biomass in the top 10 cm, approximately 15 percent in the 10 to 20 cm depth, less than 15 percent in the 20 to 30 cm depth, and less than 10 percent in the 30 to 40 cm depth. This distribution of root biomass suggests a positive feedback between vegetation and channel incision: as incision progresses, there is a loss of hydrologic connectivity, which causes a shift to a drier vegetation assemblage and decreased root structure, resulting in a reduced erosive resistance capacity in the lower zone of the streambank, thereby allowing further incision and widening.  相似文献   
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Toledo LC  Silva AC  Augusti R  Lago RM 《Chemosphere》2003,50(8):1049-1054
In this work Fenton's reagent was used to treat activated carbon saturated with organochloro compounds for the oxidation of the adsorbed contaminants and the regeneration of the carbon adsorbent. Activated carbon containing adsorbed chlorinated model substrates such as chlorobenzene, tetrachloroethylene, chloroform or 1,2-dichloropropane was treated with Fenton's reagent at room temperature resulting in a rapid consumption of the organochloro compounds. Thermogravimetric, infrared, BET surface area and MIMS adsorption studies showed that Fenton's treatment has no significant effect on the physico-chemical properties of the activated carbon. The used carbon adsorbents can be efficiently regenerated and recycled with no loss of its adsorption capacity even after five consecutive treatments with Fenton's reagent.  相似文献   
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