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281.
Luca Santini Stuart H. M. Butchart Carlo Rondinini Ana Benítez-López Jelle P. Hilbers Aafke M. Schipper Mirza Cengic Joseph A. Tobias Mark A. J. Huijbregts 《Conservation biology》2019,33(5):1084-1093
The IUCN (International Union for Conservation of Nature) Red List categories and criteria are the most widely used framework for assessing the relative extinction risk of species. The criteria are based on quantitative thresholds relating to the size, trends, and structure of species’ distributions and populations. However, data on these parameters are sparse and uncertain for many species and unavailable for others, potentially leading to their misclassification or classification as data deficient. We devised an approach that combines data on land-cover change, species-specific habitat preferences, population abundance, and dispersal distance to estimate key parameters (extent of occurrence, maximum area of occupancy, population size and trend, and degree of fragmentation) and hence predict IUCN Red List categories for species. We applied our approach to nonpelagic birds and terrestrial mammals globally (∼15,000 species). The predicted categories were fairly consistent with published IUCN Red List assessments, but more optimistic overall. We predicted 4.2% of species (467 birds and 143 mammals) to be more threatened than currently assessed and 20.2% of data deficient species (10 birds and 114 mammals) to be at risk of extinction. Incorporating the habitat fragmentation subcriterion reduced these predictions 1.5–2.3% and 6.4–14.9% (depending on the quantitative definition of fragmentation) for threatened and data deficient species, respectively, highlighting the need for improved guidance for IUCN Red List assessors on the application of this aspect of the IUCN Red List criteria. Our approach complements traditional methods of estimating parameters for IUCN Red List assessments. Furthermore, it readily provides an early-warning system to identify species potentially warranting changes in their extinction-risk category based on periodic updates of land-cover information. Given our method relies on optimistic assumptions about species distribution and abundance, all species predicted to be more at risk than currently evaluated should be prioritized for reassessment. 相似文献
282.
Growth of alfalfa in sludge-amended soils and inoculated with rhizobia produced in sludge 总被引:1,自引:0,他引:1
The efficiency of rhizobial inoculants produced in wastewater sludge used as a growth medium and as a carrier was compared with that of inoculants produced in yeast mannitol broth (YMB) medium and by using peat as a carrier. Alfalfa (Medicago sativa L.) plants were inoculated with solid and liquid Sinorhizobium meliloti inoculants and grown in pots containing two soil types (Kamouraska clay soil and Saint-André sandy soil). The effect of various levels of sludge amendment (60 and 120 kg N/ha) and nitrogen fertilizer (60 kg N/ ha) was also studied. The sludge-based inoculants showed the same symbiotic efficiency (nodulation and plant yield) as YMB-based inoculants. The inoculation increased the nodulation indexes from 4-6 to 8-12, and the rhizobial number from 10(3) (uninoculated soils) to 10(6)-10(7) cells/g in inoculated soils. However, the shoot dry weights and the nitrogen contents were not increased significantly by the inoculation. Applying sludge as an amendment enhanced the rhizobial number in soils from 10(3) to 10(4) cells/g and improved significantly the plant growth (shoot dry weights and nitrogen contents). This improvement increased with sludge rate and with the cut (three cuts). Compared with sludge, N fertilizer gave lower plant yields. The nodulation was not affected by sludge and N-fertilizer application. The texture and physico-chemical properties of soil were found to affect the yield and nitrogen content of the plants. In this study, macroelements and heavy metals were at acceptable levels and were not considered to be negative factors. 相似文献
283.
From environment to sustainability: Surveys and analysis of local agenda 21 process development in UK local authorities 总被引:1,自引:0,他引:1
Ben Tuxworth 《Local Environment》1996,1(3):277-297
Agenda 21 has come to be the most significant outcome of the Rio Summit for local government in the UK and Local Agenda 21 is emerging as the main driver for the development of local policies and programmes for sustainable development. In general, the work is being undertaken by those charged with the development of environmental policy in local authorities. Sustainability is seen as a natural extension of environmental policy work, and survey results presented confirm a gradual emergence of LA21 work from an environmental focus to a strategic approach to issues of environment, economic development, social welfare and accessibility. The level of awareness of LA21 and commitment to it in general terms appear high, but survey results suggest that the full implications of the agenda, particularly those relating to new approaches to partnership, participation and democracy, have not yet been addressed by all authorities. The author suggests that problems of corporatisation of LA21 and its relationship with traditional democratic structures remain to be tackled. The potential for the consensual approach in tackling issues of 'hard sustainability' is also discussed. 相似文献
284.
Sklaver B 《Disasters》2003,27(3):259-271
Over 13 million Humanitarian Daily Rations (HDRs) have been distributed by NGOs, international organisations and the US military since 1993. In that time, not a single technical end-user study of HDRs has been published. Nor have practical guidelines been established for HDR distribution or use. This paper seeks to establish a baseline of knowledge concerning HDRs, surveying their history, composition and distribution. Criticisms of the ration are reviewed. A comprehensive evaluation is required to understand and improve HDR distribution, end-use, perceptions, design and nutritional contents. HDRs must also be added to technical guidelines on planning nutritionally adequate rations. 相似文献
285.
Janette Ackroyd Ben Coulter Paul S. Phillips Adam D. Read 《Resources, Conservation and Recycling》2003,38(4):271-299
The business excellence through resource efficiency (betre) project aimed to increase awareness of the benefits of waste minimisation for SMEs in West Sussex, South East England. The programme was run by the West Sussex Sustainable Business Partnership, a collaboration of all West Sussex Local Authorities, the Environment Agency and EcoSys (a service provider). Betre provided a range of free business support and advice over an 18-month period including; workshops, newsletters, audits, grants and a technical Helpline. Information on environmental compliance and Best Practice for waste minimisation, recycling, energy and water efficiency was disseminated. All activities were linked with the UK government's Best Practice programmes. Although company recruitment was initially slow, betre was ultimately extremely successful at attracting companies to join; with 308 recruited. This is probably the most successful recruitment to a project, of this type, in the UK to date. Over half of the business members became actively involved and attended training events or had environmental audits. There were over 200 improvement actions identified by 64 of the participating companies. These resulted in estimated cost savings of at least £215 000 per annum. In addition, actions taken to prevent pollution and ensure compliance with environmental legislation have the potential to save businesses a further £204 000 in possible penalties. The environmental impact of the project has been significant, with reductions identified in waste (1437 tonnes), water (62 933 m3) and energy (15 million kW h—equivalent to 668 tonnes CO2). In addition to actions with directly measurable results, betre has stimulated long-term benefits by addressing pollution prevention and compliance, through the formulation of environmental policies and from the adoption of Environmental Management Systems. One of the key learning points is that it may have been better to devote less time to running training events and instead to have diverted this time to increased business support, mainly through audits. To capitalise on this success, a new project is being planned to disseminate Best Practice. 相似文献
286.
Adrienne I. Greve Jim C. Loftis Juliane B. Brown Rob R. Buirgy Ben Alexander 《Journal of the American Water Resources Association》2003,39(6):1409-1418
ABSTRACT: In 1996, the Big Thompson Watershed Forum (BTWF) was formed “to assess and protect the quality of water” in the Big Thompson Watershed in northern Colorado. However, until 1999, water quality monitoring in the watershed was performed by many state, local, and federal agencies with no coordination among programs and with few efforts toward efficiency, data comparability, or information exchange. To better meet the needs of its stakeholders, the BTWF since 1999 has been actively pursuing the design and implementation of a cooperative water quality monitoring program. The program design involved consensus building among the funding participants, primarily drinking water providers. The final design included 38 parameters to be sampled 15 times per year at 24 stream and canal locations plus two reservoirs. Although the collaborative consensus based approach has been successful for the BTWF, this approach has its drawbacks; most notable among these are the time and labor this approach requires. Also, the BTWF struggled with achieving equal representation of all interests, since those agencies that provided funding had the greatest voice in the final product. While a collaborative approach may not always be best for monitoring program design, it should be appropriate for many watershed organizations that face the common problem of severe financial constraints. 相似文献
287.
Nicholas D. Stone Ben E. Cline James Pease 《Journal of the American Water Resources Association》2002,38(2):355-365
ABSTRACT: A fundamental problem faced in developing spatially explicit, simulation‐based analyses of watershed management and policy options is determining the distribution and spatial location of agricultural resources within a watershed based on incomplete information. This paper describes the use of simulated annealing, a heuristic scheduling process, to generate an assignment of all livestock and agricultural fields in a watershed to hypothetical farms such that the combined distribution of farm types, livestock, and farmland within the watershed is a reasonable representation of watershed‐level data. Compared to a manual method using GIS‐based analysis and data from aerial photography, the heuristic method was more likely to generate realistic spatial characterizations of the distribution of agricultural resources and practices in a watershed. Also compared to the manual method, the heuristic process was considerably more efficient and could more easily accommodate multiple criteria and modifications to those criteria. 相似文献
288.
贲知明 《中国安全科学学报》1995,5(5):59-61
初步提出在一定范围内建立“安全技术咨询服务公司”的设想。当今是知识爆炸,信息大交流的时代,计算机技术的普及应用,为这种设想提供了实现的条件。人们在咨询服务系统中能方便、迅捷获得技术服务信息,帮助解决在工程施工中的各种问题。在技术力量薄弱的中、小型施工企业,将是这种服务的最大受益者。 相似文献
289.
Kambiz Haji Hajikolaei Hamed Moradi Gholamreza Vossoughi Mohammad R. Movahhedy 《Journal of Manufacturing Processes》2010,12(2):106-115
Chatter suppression in machining processes results in more material removal rate, high precision and surface quality. In this paper, two control strategies are developed to suppress chatter vibration in the turning process including a worn tool. In the first stage, a sinusoidal spindle speed variation around the mean speed is modulated to disturb the regenerative mechanism. The optimal amplitudes of the speed modulations are found based on a genetic algorithm such that the input energy to the turning process is minimized. In the second stage, to improve the response of the system which is associated with small ripples under the steady state condition, an adaptive controller is designed. In this stage, the provided external force (e.g., by a piezo-actuator) is the input variable. Results are provided for each control strategy. It is shown that if both control approaches are applied simultaneously, chatter vibration is suppressed in less time without any ripples at the steady state condition. 相似文献
290.
Kevin L. Woo Maree Hunt David Harper Nicola J. Nelson Charles H. Daugherty Ben D. Bell 《Die Naturwissenschaften》2009,96(3):415-419
By investigating the mechanisms that underlie the perception of environmental cues, we may begin to understand how the sensory
system governs behavioral responses. This is the first empirical study to examine learning and visual sensitivity in a reptile
species, the tuatara (Sphenodon punctatus). We established a non-intrusive psychophysical method by employing an instrumental paradigm in order to examine discrimination
learning and the ability to distinguish different flicker frequencies in the tuatara. Seventeen tuatara were trained under
an operant conditioning task to respond to various discriminative stimuli flickering between 2.65 and 65.09 Hz. Tuatara were
able to learn the operant task and discriminate between a constant light and flicker frequency rates between 2.65 and 45.61 Hz,
but not at 65.09 Hz. We demonstrated a reliable psychophysical method where these reptiles could learn a basic operant task
and discriminate visual stimuli in the form of flicker frequency rates. The tuatara’s ability to perceive flickering light
is comparable to that of avian, mammalian, and other reptilian species. This method is thus suitable for more comprehensive
examinations of vision and additional sensory abilities in other reptiles.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献