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71.
SUMMARY

In recent years, indigenous tenure over forest lands has emerged as a means to conserve forests while recognizing indigenous rights. There is concern, however, that indigenous reserves may not be an appropriate policy tool for sustained forest conservation. Our research examined how recognition of indigenous common-property rights has controlled agricultural expansion and conserved forests in Bosawas Biosphere Reserve, Nicaragua. We used satellite imagery with empirical data gathered in the field on land-use institutions, population pressures, and land-use practices to compare whether indigenous communities under territorial management or public management are better able to (1) control the ‘fast threat’ of frontier expansion and (2) address the long-term ecological threats posed by indigenous land-use practices and institutional changes in the region. Our findings are that indigenous residents who share common-property rights over their territories are better able to control agricultural expansion than are indigenous residents living on public lands. With respect to the long-term threats to the region, a series of simulations of possible land-use pressures demonstrate that the enforcement of territorial boundaries and further development of indigenous forest management rules will prove crucial in determining land-use capacity and deforestation over the next 50 years.  相似文献   
72.
Geologic processes strongly influence water and sediment quality in aquatic ecosystems but rarely are geologic principles incorporated into routine biomonitoring studies. We test if elevated concentrations of metals in water and sediment are restricted to streams downstream of mines or areas that may discharge mine wastes. We surveyed 198 catchments classified as "historically mined" or "unmined," and based on mineral-deposit criteria, to determine whether water and sediment quality were influenced by naturally occurring mineralized rock, by historical mining, or by a combination of both. By accounting for different geologic sources of metals to the environment, we were able to distinguish aquatic ecosystems limited by metals derived from natural processes from those due to mining. Elevated concentrations of metals in water and sediment were not restricted to mined catchments; depauperate aquatic communities were found in unmined catchments. The type and intensity of hydrothermal alteration and the mineral deposit type were important determinants of water and sediment quality as well as the aquatic community in both mined and unmined catchments. This study distinguished the effects of different rock types and geologic sources of metals on ecosystems by incorporating basic geologic processes into reference and baseline site selection, resulting in a refined assessment. Our results indicate that biomonitoring studies should account for natural sources of metals in some geologic environments as contributors to the effect of mines on aquatic ecosystems, recognizing that in mining-impacted drainages there may have been high pre-mining background metal concentrations.  相似文献   
73.
74.
Factorial design plan was experimented in Perna perna in order to find out the contribution of day exposure, Cd and Cu concentrations in water, and their interactions on metallothioneins (MT), Cd, and Cu (the dependent measured variables) in the gills. The picture obtained is more adequate than by studying the factor effect separately. Compared with the control group, the MT concentration after 22?days exposure period in the mixture of 100?μg/mL Cu and Cd is increased almost two times, showing that P. perna might be used as a biomonitor. Cd showed stronger effect than Cu on MT inducing.  相似文献   
75.
Environmental Science and Pollution Research - Anticoagulant rodenticides (ARs) are used globally to control rodent pest infestations in both urban and agricultural settings. It is well documented...  相似文献   
76.
Environmental Science and Pollution Research - The following work provides a perspective on the potential application of solar heterogeneous photocatalysis, which is a nonselective advanced...  相似文献   
77.

During gestation, essential and non-essential trace elements are transferred from the pregnant females to embryos. This study aimed to determine and compare the concentrations of seven essential trace elements (Fe, Zn, Se, Cu, Mn, Cr, Co) and six non-essential trace elements (As, Cd, V, U, Tl, Ag) in the muscle and the liver of a Munk’s pygmy devil ray pregnant female, Mobula munkiana, and its embryo. Transfer evidence of essential and non-essential trace elements was detected in M. munkiana tissues. Arsenic was found in elevated concentrations in the pregnant female and the embryo tissues. Elevated levels of Cd, V, U, and Ag were found in the pregnant female liver, but were minimal in the embryo tissue. This is the first study to investigate maternal transfer of essential and non-essential trace elements in these species and their reproductive strategy.

  相似文献   
78.
Environmental Science and Pollution Research - In this work, graphene oxide (GO) was synthesized by the modified Hummers method. The nanomaterial was characterized by FTIR and Raman spectroscopy,...  相似文献   
79.
A field study was carried out in the south of the Iberian Peninsula in an industrial area in the neighbourhood of Huelva city, SW Spain, and in a natural area (Do?ana National Park) for comparison, to estimate the genetic risk induced by environmental pollution in wild mice. Genotoxic effects in a sentinel organism, the Algerian mice (Mus spretus) free living in the industrial area were compared with animals of the same species living in the natural protected area. The single cell gel electrophoresis, or Comet assay, was performed as a genotoxicity test in peripheral blood of mice. Our results clearly show that mice free living in the contaminated area bear a high burden of genetic damage as compared with control individuals. The results suggest that the assessing of genotoxicity levels by the Comet assay in wild mice can be used as a valuable test in pollution monitoring and environmental conservation.  相似文献   
80.
Global warming is negatively affecting the environment of the planet. This situation has led to the development of international standards, such as the International Organisation for Standardization's DIS 14064‐1 and the Greenhouse Gas Protocol Corporate Standard, both of which measure corporate carbon footprints. These standards provide guidelines that can be applied to different organizational sectors. However, these are not sufficient for controlling the reduction of carbon emissions, because although they propose the use of indicators, they do not explicitly define them. In addition, in the case of emissions from wastewater treatment, they only suggest that the emissions associated with this process be considered. In the present study, an eight‐step, unified methodology based on these two international standards is proposed, focusing on direct emissions. Moreover, the step‐by‐step to data collection, calculations, and the required indicators to control the emissions are defined. The first scope considers direct emissions from sources that are owned or controlled by the company. Methane generation measurement from wastewater treatment has been included in the methodology within Scope 1, as it is the second most polluting gas after carbon dioxide, both of which give rise to global warming. The proposed methodology was tested as a case study in one of the most important companies in the food sector in Colombia.  相似文献   
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