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Data from a probability sample were used to estimate wetland and stream mitigation success from 2007 to 2009 across North Carolina (NC). "Success" was defined as whether the mitigation site met regulatory requirements in place at ...
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Data from a probability sample were used to estimate wetland and stream mitigation success from 2007 to 2009 across North Carolina (NC). "Success" was defined as whether the mitigation site met regulatory requirements in place at the time of construction. Analytical results were weighted by both component counts and mitigation size. Overall mitigation success (including preservation) was estimated at 74 % (SE = 3 %) for wetlands and 75 % (SE = 4 %) for streams in NC. Compared to the results of previous studies, wetland mitigation success rates had increased since the mid-1990s. Differences between mitigation providers (mitigation banks, NC Ecosystem Enhancement Program's design-bid-build and full-delivery programs, NC Department of Transportation and private permittee-responsible mitigation) were generally not significant although permittee-responsible mitigation yielded higher success rates in certain circumstances. Both wetland and stream preservation showed high rates of success and the stream enhancement success rate was significantly higher than that of stream restoration. Additional statistically significant differences when mitigation size was considered included: (1) the Piedmont yielded a lower stream mitigation success rate than other areas of the state, and (2) recently constructed wetland mitigation projects demonstrated a lower success rate than those built prior to 2002. Opportunities for improvement exist in the areas of regulatory record-keeping, understanding the relationship between post-construction establishment and long-term ecological trajectories of stream and wetland restoration projects, incorporation of numeric ecological metrics into mitigation monitoring and success criteria, and adaptation of stream mitigation designs to achieve greater success in the Piedmont.
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Variational quantum eigensolvers offer a small-scale testbed to demonstrate the performance of error mitigation techniques with low experimental overhead. We present successful error mitigation by applying the recently proposed sy...
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Variational quantum eigensolvers offer a small-scale testbed to demonstrate the performance of error mitigation techniques with low experimental overhead. We present successful error mitigation by applying the recently proposed symmetry verification technique to the experimental estimation of the ground-state energy and ground state of the hydrogen molecule. A finely adjustable exchange interaction between two qubits in a circuit QED processor efficiently prepares variational ansatz states in the single-excitation subspace respecting the parity symmetry of the qubit-mapped Hamiltonian. Symmetry verification improves the energy and state estimates by mitigating the effects of qubit relaxation and residual qubit excitation, which violate the symmetry. A full-density-matrix simulation matching the experiment dissects the contribution of these mechanisms from other calibrated error sources. Enforcing positivity of the measured density matrix via scalable convex optimization correlates the energy and state estimate improvements when using symmetry verification, with interesting implications for determining system properties beyond the ground-state energy.
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This paper reviews the gear parameters responsible for loggerhead sea turtle (Caretta caretta) capture and mortality while taking into account the mitigation measures tested in the Mediterranean Sea. Incidental catch is considered...
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This paper reviews the gear parameters responsible for loggerhead sea turtle (Caretta caretta) capture and mortality while taking into account the mitigation measures tested in the Mediterranean Sea. Incidental catch is considered as one of the major threats for turtle survival; however, the loggerhead bycatch estimated in different areas seems to be unrealistic, which highlights the need of a method for homogenising the estimates. Drifting longlines and bottom trawls have the greatest impact on Mediterranean turtle populations, respectively in pelagic and demersal phase, while passive nets (gillnets and trammel nets) seem to be responsible for the highest direct mortality, due to drowning. Most of the experiments available for the Mediterranean are focused on drifting longline. The longline parameters, hook shape and size, bait type, setting position and the reaction to sensory stimuli, strongly affect the sea turtle bycatch and mortality. Circle hooks have the potential to reduce turtle mortality only in certain fisheries and areas; larger hooks are less likely to be swallowed by turtles due to physical constraints of the mouth, reducing the mortality rate and the catch of juveniles; branchlines, once ingested, appear to be one of the major causes of sea turtle mortality; squid bait, which consistently catches more turtles than mackerel, and lightsticks, which strongly attract turtles, should be banned, at least in some areas and seasons. On the contrary only two bottom trawl studies are available from the Mediterranean. Turtle excluder devices have been tested with promising results in Turkey and Italy, even if the loss of large fish should be carefully investigated. For set nets no practical solutions are available at this time. The analysis allows the conclusion that technical parameters affecting turtle bycatch and mortality should only be studied one at a time, in order to avoid inconclusive results, studies on post-release mortality should be implemented and finally fishermen cooperation is paramount in reducing turtle bycatch and mortality.
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The U.S. Environmental Protection Agency and U.S. Army Corps of Engineers completed revisions to the Mitigation Rule of the Clean Water Act in 2008. These revisions encourage states to carry out mitigation in a watershed context, ...
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The U.S. Environmental Protection Agency and U.S. Army Corps of Engineers completed revisions to the Mitigation Rule of the Clean Water Act in 2008. These revisions encourage states to carry out mitigation in a watershed context, prioritizing mitigation site design and placement by overall watershed need, to the extent appropriate and practicable (33 C.F.R. 332.3(c)). States are expected to establish monitoring programs and measureable performance standards for mitigation wetlands. In Pennsylvania, hydrogeomorphic (HGM)-based assessments involving 222 reference wetlands were used to compare mitigation wetland performance. For this study, 72 mitigation wetlands were sampled in 2007 and 2008 from three categories - Pennsylvania Wetland Replacement Program sites, Pennsylvania Department of Transportation mitigation banks, and permit required compensatory mitigation sites. Mitigation wetlands were intensively sampled using a Level 3 - Intensive methodology developed by Riparia. Field data and GIS computed variables were used to derive the scores of 10 HGM functional capacities. Overall, mitigation sites displayed lower potential to perform a characteristic wetland function than reference wetlands. Depressions show the greatest discrepancy, while fringing sites showed the least amount of difference from reference scores. Mitigation site size, age, and type were not significant factors in functional capacity index scores.
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To improve the reliability of sectoral mitigation potential and cost analysis, this paper made an in-depth exploration into China's electricity sector's thermal efficiency and inner structure. It is found that unlike what many lit...
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To improve the reliability of sectoral mitigation potential and cost analysis, this paper made an in-depth exploration into China's electricity sector's thermal efficiency and inner structure. It is found that unlike what many literatures portray, China is actually among the world's leaders in coal-fired power plants' generating efficiencies; besides, although there are still numerous small and inefficient generating units in the current generation fleet, many of them are in fact playing important roles in supporting local economic development, meeting peak load needs, balancing heat and electricity supply and providing job opportunities to the local economy, therefore their existence does not necessarily mean low-cost mitigation potential. Given the efficiency and structural characteristics of China's electricity sector, it is pointed out that some other mitigation options, such as demand side management, IGCC and renewable energy as well as the break-through of CCS technology may play an even more important role in emission reduction. Considering the significant lock-in effects in electricity sector, it is warned that China, if continues putting majority investment in large and advanced coal-fired generating units, will face another round of chasing-after for the new and advanced renewable generation technologies. Therefore China should put more efforts in renewable generation technologies now.
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Early action refers to activities undertaken prior to a regulatory program or generation of services prior to mitigation of impacts elsewhere. In U.S. environmental markets, early action could reduce lags in environmental performa...
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Early action refers to activities undertaken prior to a regulatory program or generation of services prior to mitigation of impacts elsewhere. In U.S. environmental markets, early action could reduce lags in environmental performance, improve outcomes, and encourage innovation in mitigation approaches. Multiple tools have emerged for encouraging early action in environmental markets. Several tools have also been deployed in markets, providing valuable insight into their function. This paper presents a systematic review of early action tools and describes their use in wetland and stream mitigation, species and habitat banking, greenhouse gas mitigation, and water quality trading. It finds that incentives necessary to motivate sellers differ from those motivating buyers. The tool or approach best suited to encourage early action also varies as conditions change. Anecdotal evidence suggests the potential for benefits to accrue from early action, but additional data are needed to inform the use of specific tools.
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The mitigation hierarchy (avoid, minimize, restore/rehabilitate and, lastly, offset or compensate) is one of the
key regulatory mechanisms that exists to include biodiversity protection in land-use planning. Implementing the
mit...
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The mitigation hierarchy (avoid, minimize, restore/rehabilitate and, lastly, offset or compensate) is one of the
key regulatory mechanisms that exists to include biodiversity protection in land-use planning. Implementing the
mitigation hierarchy requires the use by practitioners (developers, environmental consultants and government
agencies) of operational mitigation assessment methods, or offset sizing methods. This study focused on one
aspect of operationality: usefulness. Through an approach based on ergonomics, we analysed practices used in
the field in order to concretely identify in what way an offset sizing method is useful to developers, consultants
and public officials. The findings showed that sizing offset measures is a collective process involving all these
stakeholders, that these practitioners vary significantly in their level of knowledge about ecology and their
degree of expertise in the mitigation hierarchy, and that each method is not equally useful for each type of
stakeholder. Our conclusion is that to improve operationality, these methods must be adapted into tools that are
relevant to the specific user and context.
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Purpose The dependence on the use of information systems for nearly every activity and functions in the internet is increasingly high. This form of interconnectedness has bolstered national economies, enhanced how governments inte...
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Purpose The dependence on the use of information systems for nearly every activity and functions in the internet is increasingly high. This form of interconnectedness has bolstered national economies, enhanced how governments interact with their citizens and how ordinary people connect with friends and family. However, this dependence has equally resulted to a high rise in vulnerability, threat and risk associated with more use of information and communication technology. Cyber-attacks that have the potential to disrupt or damage information system infrastructure are getting more complex with some level of sophistication. Traditional protection of information system infrastructure is no longer sufficient; systems have proven to be immune to failure or incidents. This paper aims to ensure that there is a continuous availability of services through a fail-safe proof. Design/methodology/approach MYSQL replication technique was used to develop a model based on three-tier layers using the principle of network interdependency and the replication techniques. Tier 1 depicts a Telecom organization serving as service provider that provides internet service to Tier 2 organization – a Bank; Tier 3 is the financial App that can be used by bank staff and customers. The fail-safe mode integrated mechanism enables Tier 3 to continue to render its services in the event of an attack on Tier 1 such as DDoS without disruption. Findings This technique succeeded in mitigating the loss of data if cyber incident occurred or reception of uninterrupted services is countered, which give rise to future master-to-master architecture. Research limitations/implications The study conducted is limited to the design and development of a fail-safe system for interdependent networks or systems using MYSQL replication technique. Originality/value In an interdependent environment such as the cyberspace, the sectors are interdependent for optimal results. The originality of the work ensures that there is availability of services which is sustained and that data integrity is assured using the fail-safe technique based on MySQL replication method.
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Net-zero targets imply that continuing residual emissions will be balanced by carbon dioxide removal. However, residual emissions are typically not well defined, conceptually or quantitatively. We analysed governments' long-term s...
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Net-zero targets imply that continuing residual emissions will be balanced by carbon dioxide removal. However, residual emissions are typically not well defined, conceptually or quantitatively. We analysed governments' long-term strategies submitted to the UNFCCC to explore projections of residual emissions, including amounts and sectors. We found substantial levels of residual emissions at net-zero greenhouse gas emissions, on average 18% of current emissions for Annex I countries. The majority of strategies were imprecise about which sectors residual emissions would originate from, and few offered specific projections of how residual emissions could be balanced by carbon removal. Our findings indicate the need for a consistent definition of residual emissions, as well as processes that standardize and compare expectations about residual emissions across countries. This is necessary for two reasons: to avoid projections of excessive residuals and correspondent unsustainable or unfeasible carbon-removal levels and to send clearer signals about the temporality of fossil fuel use. Residual emissions, as a noticeable component of net-zero plans, should be analysed transparently and with specificity. By examining the national long-term strategies, the authors find that currently residual emissions are not clearly defined and are unlikely to be balanced by land-based carbon removal.
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