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281.
Peri-urban forest monitoring requires indicators of vegetation damage. An example is the sacred fir (Abies religiosa) forests surrounding Mexico City, which have been heavily exposed to tropospheric ozone, a harmful pollutant, for over 4 decades. We developed a participatory monitoring system with which local community members and scientists generated data on ozone tree damage. Santa Rosa Xochiac rangers (13) used the digital tool KoboToolBox to record ozone damage to trees, tree height, tree ages, tree condition, tree position, and whether the tree had been planted. Thirty-five percent of the trees (n = 1765) had ozone damage. Younger trees had a lower percentage of foliage damaged by ozone than older trees (p < 0.0001), and asymptomatic trees tended to be younger (p < 0.0001). Symptomatic trees were taller than asymptomatic trees of the same age (R2c = 0.43, R2m = 0.27). Involving local communities facilitated forest monitoring and using digital technology improved data quality. This participatory system can be used to monitor forest condition change over time and thus aids restoration efforts driven by government or local communities’ interests, facilitating local decision-making.  相似文献   
282.
CO2 utilizations are essential to curbing the greenhouse gas effect and managing the environmental pollutant in an energy-efficient and economically-sound manner.This paper seeks to critically analyze these technologies in the context of each other and highlight the most important utilization avenues available thus far.This review will introduce and analyze each major pathway,and discuss the overall applicability,potential extent,and major limitations of each of these pathways to util...  相似文献   
283.
This study corroborates the importance of United Nations Sustainable Development Goal 7 (SDG-7), intended to ensure access to affordable, reliable, sustainable energy for all, and SDG-8, designed to promote decent work and sustainable economic growth. This article is motivated by the highlighted SDGs and empirically explores the long-run and causality relationship between energy consumption, urbanization, trade openness, and economic growth for annual frequency data from 1965 to 2021 for the case of Mexico. To this end, we leverage the use of fully modified ordinary least squares, dynamic ordinary least squares, and canonical regression estimation methods, while for the direction of causality, the gradual shift and wavelet coherence methods are used. According to the Autoregressive distributed lag (ARDL), the bounds test traces a long-run relationship between the outlined variables over the sampled period. Empirical evidence validates the energy-induced growth hypothesis. This result resonates with the causality analysis, where energy consumption drives economic growth one way in Mexico. This suggests that Mexico cannot embark on energy-conservative policies, as such actions will hurt economic progress. In addition, unidirectional causality is seen between urbanization, trade openness, and economic growth. These findings have far-reaching implications for economic growth and macroeconomic indicators in Mexico. More insights are highlighted in the concluding section.  相似文献   
284.
The problem of forest degradation and loss has become the concern of many countries. To address this challenge, some collaborate in sustainable forest management. The most successful outcomes, however, are observed where local participation is an essential part of conservation efforts. In Ghana, forests have experienced various degrees of exploitation over the years, resulting in their ecological decline. Despite its designation as a protected area for biodiversity and ecosystem services, the Atewa Range Forest Reserve in Ghana has been significantly impacted by deforestation, illegal mining, and other destructive activities. The purpose of this paper is to examine ecologically based management approaches that could be adopted to generate beneficial outcomes for all forest stakeholders and actors in Ghana. The study sampled forest stakeholders in Kwabeng, the administrative capital of the Atewa West District, to understand forest governance challenges and outline strategies for overcoming them. The study revealed that a bottom-up all-inclusive approach to managing forest resources is necessary. This paper, therefore, proposes an integrated forest governance that prioritizes the UN Sustainable Development Goal 15—Life on Land-related to forest preservation.  相似文献   
285.
The performance of gaseous air cleaners for commercial and residential buildings has typically been evaluated using test protocols developed for a controlled laboratory chamber or a test duct. It is currently unknown how laboratory measurements relate to the actual performance of an air cleaner installed in a real building. However, to date, there are no air cleaner field test protocols available, thereby limiting the existing field data. The National Institute of Standards and Technology (NIST) has conducted a series of experiments to support test procedure development for evaluating the installed performance of gaseous air cleaning equipment, as well as metrics for characterizing field performance. To date, over 100 experiments have been completed, of which 23 portable air cleaner experiments and 6 in-duct air cleaner experiments are described in this paper. Tests were conducted in a finished three-bedroom/two-bathroom manufactured house equipped with several gas chromatographs to semi-continuously measure air change rates and volatile organic compound concentrations. Experimental variables included air cleaner location, isolation of zones by closing doors, and contaminant source location. For each experiment, air cleaner removal of decane was directly measured using the air cleaner inlet and outlet concentrations, as well as with mass balance analyses using measured room concentrations. With a verified mass balance model, a field performance metric was developed to compare installed whole-building performance to the performance predicted by a laboratory result. The results provide insight into the protocols and metrics that might prove useful for characterizing the field performance of air cleaners as well as the impact of air cleaner removal on zonal concentration levels in a variety of situations.  相似文献   
286.
A resident population of 13 black rhinoceros ( Diceros bicornis ) persist in Ngorongoro Crater, Tanzania. The effective population size ( N e ) may be as few as 5 animals. Projected growth for this population suggests that the effective population size will remain small for the near future, threatening this Iocal population with extinction due to the stochastic factors associated with small population size. A summary of historic and recent demographic data for this population reveals a population crash during the period of heavy poaching that affected this species throughout its range. Although poaching of this species has been brought under control the population remains small. These data and models of projected population growth argue for consideration of more-intensive management within the framework of the small population paradigm. This case is an example of applied conservation resulting from this paradigm used in conjunction with rather than competing with the declining population paradigm. We identify additional monitoring, particularly of density-dependent behaviors, that will be necessary for designing a successful management program. Finally, the use of molecular markers for developing an accurate pedigree for this population is suggested in order to maintain a genetically healthy population. These strategies have broad applicability to black rhinoceros conservation throughout Africa.  相似文献   
287.
ABSTRACT: The relationship between chlorophyll u, total phosphorus, secchi disk depth, and trophic state were examined using data on U.S. lakes collected by U.S. EPA's National Eutrophication Survey. By comparing predicted secchi disk depths with observed summer secchi disk depths in 757 lakes, it was determined that in many lakes non-chlorophyll related light attenuation is important in controlling the amount of chlorophyll u produced per unit of total phosphorus. Ranking of 44 lakes by 18 different trophic state measurements and single and multivariable indices were compared with rankings provided by mean summer ambient total phosphorus and chlorophyll u. The trophic state measurements and indices were much more successful in ranking the lakes against total phosphorus than chlorophyll u, indicating that there are differences in the relative trophic rankings of many of the lakes depending upon whether primary nutrients or biological manifestations are used as the ranking mechanism. If the manifestations of nutrients rather than their absolute levels are the primary criteria for beneficial use of lakes, the use of many of the commonly employed trophic state measurements, which assume or imply that there is a constant relationship between total phosphorus or secchi disk and chlorophyll, can lead to erroneous conclusions and unnecessary costly management controls. Secchi disk measurements may be more useful as a predictor of ambient lake total phosphorus concentrations than of chlorophyll.  相似文献   
288.
/ One attempt to quantify targets for rehabilitating degraded aquatic ecosystems has been through a United States-Canada program to develop and implement comprehensive remedial action plans (RAPs) to restore beneficial uses in 42 Great Lakes Areas of Concern. The International Joint Commission has facilitated agreement on listing/delisting guidelines for determining when use impairments exist in areas of concern and when uses have been restored, while federal/state/provincial governments and local stakeholders have provided leadership in establishing quantitative targets for restoring uses and in determining how to achieve them. The listing/delisting guidelines have been instrumental in helping reach agreement on problem definition (lack of agreement on problem definition has historically been used as a reason to delay action) and reaching agreement on quantitative targets for restoring uses. Quantitative, ecosystem-based targets are being used to drive the RAP process, help organizations pursue a common mission of restoring uses, and help achieve greater accountability. As a priority, the target-setting process must also recognize the importance of establishing both short- and long-term milestones in order to measure and celebrate incremental progress in restoring uses.KEY WORDS: Use impairments; Restoring uses; Quantitative targets  相似文献   
289.
290.
Municipal Solid Waste Management in the Accra Metropolitan Area, Ghana   总被引:1,自引:0,他引:1  
Municipal solid waste management in Accra, Ghana, is at present delivered in an unsustainable manner. Due to uncontrolled urbanisation, large quantities of waste are generated daily in Accra, and this exerts much pressure on an over strained solid waste management system. Coupled with weak institutional capacity, and lack of resources, both human and capital, the city authorities face difficulties in ensuring that all the waste generated in the city is collected for disposal. Home collection of waste is limited to high and, some middle income areas while the poor are left to contend with the problem on their own. This leads to indiscriminate disposal of waste in surface drains, canals and streams, creating unsanitary, and unsightly environments in many parts of the city.  相似文献   
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