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121.
Quantifying species recovery and conservation success to develop an IUCN Green List of Species
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H. Resit Akçakaya Elizabeth L. Bennett Thomas M. Brooks Molly K. Grace Anna Heath Simon Hedges Craig Hilton‐Taylor Michael Hoffmann David A. Keith Barney Long David P. Mallon Erik Meijaard E.J. Milner‐Gulland Ana S.L. Rodrigues Jon Paul Rodriguez P.J. Stephenson Simon N. Stuart Richard P. Young 《Conservation biology》2018,32(5):1128-1138
Stopping declines in biodiversity is critically important, but it is only a first step toward achieving more ambitious conservation goals. The absence of an objective and practical definition of species recovery that is applicable across taxonomic groups leads to inconsistent targets in recovery plans and frustrates reporting and maximization of conservation impact. We devised a framework for comprehensively assessing species recovery and conservation success. We propose a definition of a fully recovered species that emphasizes viability, ecological functionality, and representation; and use counterfactual approaches to quantify degree of recovery. This allowed us to calculate a set of 4 conservation metrics that demonstrate impacts of conservation efforts to date (conservation legacy); identify dependence of a species on conservation actions (conservation dependence); quantify expected gains resulting from conservation action in the medium term (conservation gain); and specify requirements to achieve maximum plausible recovery over the long term (recovery potential). These metrics can incentivize the establishment and achievement of ambitious conservation targets. We illustrate their use by applying the framework to a vertebrate, an invertebrate, and a woody and an herbaceous plant. Our approach is a preliminary framework for an International Union for Conservation of Nature (IUCN) Green List of Species, which was mandated by a resolution of IUCN members in 2012. Although there are several challenges in applying our proposed framework to a wide range of species, we believe its further development, implementation, and integration with the IUCN Red List of Threatened Species will help catalyze a positive and ambitious vision for conservation that will drive sustained conservation action. 相似文献
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Scot D. Anderson Taylor K. Chapple Salvador J. Jorgensen A. Peter Klimley Barbara A. Block 《Marine Biology》2011,158(6):1233-1237
Mark-recapture techniques can be used to estimate white shark (Carcharodon carcharias) population abundance. These frameworks are based on assumptions that marks are conserved and animals are present at the
sampling location over the entire duration of the study. Though these assumptions have been validated across short-time scales
for white sharks, long-term studies of population trends are dependent on these assumptions being valid across longer periods.
We use 22 years of photographic data from aggregation sites in central California to support the use of dorsal fin morphology
as long-term individual identifiers. We identified five individuals over 16–22 years, which support the use of dorsal fins
as long-time individual identifiers, illustrate strong yearly site fidelity to coastal aggregation sites across extended time
periods (decades), and provide the first empirical validation of white shark longevity >22 years. These findings support the
use of fin morphology in mark-recapture frameworks for white sharks. 相似文献
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Most species of benthic marine invertebrates have a single mode of larval development. Poecilogonous species are those that
produce more than one type of larval offspring. Reports of variable development within one species, especially in combination
with widely differing ecological habitat, are frequently attributed to cryptic species. The spionid polychaete Boccardia proboscidea Hartman, 1940 exhibits development that varies both within a single brood and among broods produced by different females.
Some females have planktotrophic development and produce many small larvae with a 2 week planktonic period before metamorphosis.
Other females produce broods containing both planktotrophic larvae as well as nurse-egg-ingesting (adelphophagic) offspring
that hatch as juveniles. Molecular analysis (RAPD-PCR) showed that a significant proportion of genetic variance is attributable
to geographic origin, and not to developmental type. Adults of both developmental types showed no consistent differences in
taxonomically important features (e.g. type and arrangement of chaetae, modified fifth setiger, caruncle, branchiae, pygidium)
when examined with SEM. These data support the hypothesis that developmental variability in this species is a case of poecilogony,
and is not attributable to cryptic species.
Received: 21 April 1998 / Accepted: 20 April 1999 相似文献
125.
P.L. Livingstone K. Magliano K. Gürer P.D. Allen K.M. Zhang Q. Ying B.S. Jackson A. Kaduwela M. Kleeman L.F. Woodhouse K. Turkiewicz L.W. Horowitz K. Scott D. Johnson C. Taylor G. O'Brien J. DaMassa B.E. Croes F. Binkowski D. Byun 《Atmospheric environment (Oxford, England : 1994)》2009,43(37):5971-5977
We investigated a two-week episode with high PM concentrations in California Central Valley during the Christmas–New Year of 2000–2001 using a modeling system that consists of a computationally efficient, 3-D photochemical–microphysical transport model, a mesoscale meteorological model, emission models, and an evaluation package. One hundred simulations were conducted with fine resolutions and observational constraints, to reproduce spatial and temporal features of observed PM concentrations and to understand the formation mechanism of the episode. Simulated PM concentrations consist of secondary inorganic components, mainly ammonium nitrate, and total carbon in areas with elevated concentrations in the accumulation mode, and consist of mainly dust and sea salt in the coarse mode. Simulated oxidants and nitrate were significantly elevated over the valley, and the latter showed much less amplitude than the former. Simulated PM concentrations were evaluated with observations systematically with spatially and temporally paired method, a more restrictive multivariate method (NMFROC), and a more flexible “gradient evaluation” method. The paired evaluation shows that high correlation coefficient (R = ~0.8) and low fractional error (FE = ~0.1) could be achieved at stations with elevated 24-h concentration of PM in the accumulation mode in some simulations. The NMFROC method was used to extract useful information from seemingly failed simulations. A “gradient evaluation” method is introduced here to extract additional information from simulations. We found that emission reductions of NOx and AVOC showed similar effects on percentage basis in different areas, and both are more effective than reducing NH3 for abating elevated concentrations of accumulation mode PM in California Central Valley during the winter episode. 相似文献
126.
An assessment of Spain's Programa AGUA and its implications for sustainable water management in the province of Almería, southeast Spain 总被引:1,自引:0,他引:1
Spain's Programa AGUA was proposed in 2004 as a replacement for the Spanish National Hydrological Plan and represented a fundamental policy shift in national water management from large inter-basin water transfers to a commitment to desalination. Twenty-one desalination facilities are planned for six provinces on the Spanish Mediterranean coast to supplement their water needs. These include the province of Almería that for the last 30 years has endured a net water abstraction overdraft leading to serious reservoir depletion and groundwater imbalances. Rising water use is a result of increasing demand to support irrigated agriculture (e.g. greenhouse horticulture) and for domestic needs (e.g. rapid urban growth and tourism development), which has led observers to question Almería's long-term water sustainability. Desalinated water alone is unlikely to be sufficient to make up these water deficits and water-users will have to accept a move to full-price water recovery by 2010 under the European Union (EU) Water Framework Directive of which Spain is a signatory. Anticipated water efficiencies resulting from higher water tariffs, increasing water reuse and water infrastructure improvements (including inter-basin transfers), in conjunction with increasing use of desalinated water, are expected to address the province's current water overdraft. However, Almería will need to balance its planned initiatives against long-term estimates of projected agricultural and domestic development and the environmental consequences of adopting a desalination-supported water future. 相似文献
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The suggestion that utility is logically necessary for behavioural adjustments to be made in response to changes in intrinsic risk is fundamental to risk homeostasis theory (RHT). However, the methodology used to investigate RHT — analysis of road traffic accidents — is ill-suited to the investigation of this assertion. The role of utility and intrinsic risk as possible determinants of behavioural compensation were therefore examined experimentally across 14 specific behaviours using the Aston Driving Simulator. RHT predicts that these two factors act in a multiplicative way to form a statistical interaction. It also predicts that the behavioural pathways through which the effect manifests itself should be reconcilable with the concept of utility. Both predictions received little support in this experiment, suggesting that utility and intrinsic risk operate as independent factors: both factors produced significant main effects across a number of behaviours. This finding, if it can be generalised, implies that, contrary to mathematically-based models of danger compensation and the traditional model of risk homeostasis, utility is not logically necessary for behavioural compensation in response to a change in intrinsic risk. 相似文献