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51.
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
52.
Mapping Outlets of Iowa Flood Center and National Water Center River Networks for Hydrologic Model Comparison 下载免费PDF全文
Felipe Quintero Witold F. Krajewski 《Journal of the American Water Resources Association》2018,54(1):28-39
River networks based on Digital Elevation Model (DEM) data differ depending on the DEM resolution, accuracy, and algorithms used for network extraction. As spatial scale increases, the differences diminish. This study explores methods that identify the scale where networks obtained by different methods agree within some margin of error. The problem is relevant for comparing hydrologic models built around the two networks. An example is the need to compare streamflow prediction from the Hillslope Link Model (HLM) operated by the Iowa Flood Center (IFC) and the National Water Model (NWM) operated by the National Water Center of the National Oceanic and Atmospheric Administration. The HLM uses landscape decomposition into hillslopes and channel links while the NWM uses the NHDPlus dataset as its basic spatial support. While the HLM resolves the scale of the NHDPlus, the outlets of the latter do not necessarily correspond to the nodes of the HLM model. The authors evaluated two methods to map the outlets of NHDPlus to outlets on the IFC network. The methods compare the upstream areas of the channels and their spatial location. Both methods displayed similar performance and identified matches for about 80% of the outlets with a tolerance of 10% in errors in the upstream area. As the aggregation scale increases, the number of matches also increases. At the scale of 100 km2, 90% of the outlets have matches with tolerance of 5%. The authors recommend this scale for comparing the HLM and NWM streamflow predictions. 相似文献
53.
Conservation practitioners, natural resource managers, and environmental stewards often seek out scientific contributions to inform decision-making. This body of science only becomes actionable when motivated by decision makers considering alternative courses of action. Many in the science community equate addressing stakeholder science needs with delivering actionable science. However, not all efforts to address science needs deliver actionable science, suggesting that the synonymous use of these two constructs (delivering actionable science and addressing science needs) is not trivial. This can be the case when such needs are conveyed by people who neglect decision makers responsible for articulating a priority management concern and for specifying how the anticipated scientific information will aid the decision-making process. We argue that the actors responsible for articulating these science needs and the process used to identify them are decisive factors in the ability to deliver actionable science, stressing the importance of examining the provenance and the determination of science needs. Guided by a desire to enhance communication and cross-literacy between scientists and decision makers, we identified categories of actors who may inappropriately declare science needs (e.g., applied scientists with and without regulatory affiliation, external influencers, reluctant decision makers, agents in place of decision makers, and boundary organization representatives). We also emphasize the importance of, and general approach to, undertaking needs assessments or gap analyses as a means to identify priority science needs. We conclude that basic stipulations to legitimize actionable science, such as the declaration of decisions of interest that motivate science needs and using a robust process to identify priority information gaps, are not always satisfied and require verification. To alleviate these shortcomings, we formulated practical suggestions for consideration by applied scientists, decision makers, research funding entities, and boundary organizations to help foster conditions that lead to science output being truly actionable. 相似文献
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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
56.
The most recent intervention on the coastline of Espinho, located on the Portuguese West Atlantic coast, was part of the General
Plan for Coastal Protection in 1980/81. As a result, two unusually large groins/headlands were built which were reinforced
and enlarged in 1997, slightly changing their geometry and orientation. However, due to the decreased sediment supply from
the north and the impact of energetic sea conditions common to the northwest coast of Portugal the coastal evolution has not
developed as desired, although in general terms the initial expectations were fulfilled. The numerical modelling of the Espinho
coastline using SMC software focused on both hydrodynamic and hydromorphological aspects. The purpose of this study is to
analyse the most vulnerable areas of the Espinho seafront for current velocities and littoral drift, as well as to confirm
the effectiveness of the two groins in terms of coastal protection. To achieve this, various simulations were performed, taking
into account diverse sea conditions. 相似文献
57.
The management of small-scale freshwater fisheries in Amazon has been based usually on surveys of urban markets, while fisheries
of rural villages have gone unnoticed. We compared the fishing characteristics (catch, effort and selectivity) between an
urban market and five small villages in the Lower Tocantins River (Brazilian Amazon), downstream from a large reservoir. We
recorded 86 and 601 fish landings in the urban market and villages, respectively, using the same methodology. The urban fishers
showed higher catch per unit of effort, higher amount of ice (related to a higher fishing effort, as ice is used to store
fish catches) and larger crew size per fishing trip, but village fishers had a higher estimated annual fish production. Conversely,
urban and village fishers used similar fishing gear (gillnets) and the main fish species caught were the same. However, village
fishers showed more diverse strategies regarding gear, habitats and fish caught. Therefore, although it underestimated the
total amount of fish caught in the Lower Tocantins River region, the data from the urban market could be a reliable indicator
of main fish species exploited and fishing gear used by village fishers. Monitoring and management should consider the differences
and similarities between urban and rural fisheries, in Amazon and in other tropical regions. 相似文献
58.
Baraj B Niencheski F Fillmann G De Martinez Gaspar Martins C 《Environmental monitoring and assessment》2011,179(1-4):155-162
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
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Guimarães Barbara Maria Ribeiro Scatolino Mário Vanoli Martins Maria Alice Ferreira Saulo Rocha Mendes Lourival Marin Lima José Tarcísio Junior Mario Guimarães Tonoli Gustavo Henrique Denzin 《Environmental science and pollution research international》2022,29(6):8665-8683
Environmental Science and Pollution Research - The growing demand for products with lower environmental impact and the extensive applicability of cellulose nanofibrils (CNFs) have received... 相似文献