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201.
Charles H. Eccleston 《环境质量管理》1999,8(3):43-48
The National Environmental Policy Act (NEPA) of 1969 provides the basic national charter for protection of the environment in the United States. Today NEPA provides an environmental policy model, emulated by nations around the world. Recently, questions have been raised regarding the appropriateness and under what conditions it makes sense to combine the preparation of a NEPA analysis with the International Organization for Standardization (ISO) ISO 14000 standards for Life-Cycle Assessment (LCA). This article advances a decision-making tool consisting of six discrete factors for use in determining when it is appropriate to perform an integrated NEPA/LCA analysis. Properly applied, this tool should reduce the risk that an LCA may be inappropriately prepared and integrated with a NEPA analysis.© 1999 John Wiley & Sons, Inc. 相似文献
202.
The number of males in primate social groups: a comparative test of the socioecological model 总被引:2,自引:2,他引:0
Charles L. Nunn 《Behavioral ecology and sociobiology》1999,46(1):1-13
As applied to polygynous mammals, the socioecological model assumes that environmental risks and resources determine the
spatial and temporal distribution of females, which then sets male strategies for monopolizing fertile matings. The effects
of female spatial distribution (i.e., female number) and temporal overlap (female mating synchrony) have been examined in
comparative studies of primates, but the relative influence of these two factors on male monopolization potential (the number
of males) remains unclear. One particular problem is that female synchrony is more difficult to estimate than female number.
This paper uses multivariate statistical methods and three independent estimates of female synchrony to assess the roles of
spatial and temporal effects in the context of a phylogenetically corrected dataset. These analyses are based on sensitivity
analyses involving a total of four phylogenies, with two sets of branch length estimates for each tree, and one nonphylogenetic
analysis in which species values are used (because male behavior may represent a facultative response to the distribution
of females). The results show: (1) that breeding seasonality predicts male number (statistically significant in six out of
nine sensitivity tests); (2) that expected female overlap, after controlling for female group size using residuals, also accounts
for the number of males in primate groups (significant in eight out of nine tests), and (3) that actual estimates of female
mating synchrony predict male number, again after correcting for female group size (significant in five out of nine tests).
Nonsignificant results are in the predicted direction, and female group size is significant in all statistical tests. These
analyses therefore demonstrate an independent influence of female temporal overlap on male monopolization strategies in mammalian
social systems.
Received: 24 July 1998 / Received in revised form: 5 February 1999 / Accepted: 7 February 1999 相似文献
203.
Becky L. Williams Charles T. Hanifin Edmund D. Brodie Jr Edmund D. Brodie III 《Chemoecology》2010,20(4):285-290
Lethal chemical defenses in prey species can have profound effects on interactions with predators. The presence of lethal defenses in prey can correct the selective imbalance suggested by the life-dinner principle in which the fitness consequences of an encounter between predator and prey should be much greater for the prey species than the predator. Despite the apparent adaptive advantages of lethality the evolution of deadly prey presents a fundamental dilemma. How might lethal defenses confer an individual fitness advantage if both predators and prey die during interactions? We examined the interaction between the rough-skinned newt (Taricha granulosa), which contains a powerful neurotoxin called tetrodotoxin (TTX), and the common garter snake (Thamnophis sirtalis). In some sympatric populations, Th. sirtalis have evolved physiological resistance to TTX. Whether the newts’ toxin confers protection from snake predators or has been disarmed by the snakes’ physiological resistance has not yet been directly tested. In predator–prey trials, newts that were rejected by snakes had greater concentrations of TTX in their skin (4.52 ± 3.49 mg TTX/g skin) than those that were eaten (1.72 ± 1.53 mg TTX/g skin). Despite the plethora of taxa that appear to use TTX defensively, this is the first direct and quantitative demonstration of the antipredator efficacy of TTX. Because the survival probability of a newt (and thus fitness) is affected by individual TTX concentration, selection can drive the escalation of toxin levels in newts. The variable fitness consequences associated with both TTX levels of newts and resistance to TTX in snakes that may promote a strong and symmetrical coevolutionary relationship have now been demonstrated. 相似文献
204.
Three strains of the chain-forming diatom Skeletonema marinoi, differing in their production of polyunsaturated aldehydes (PUA) and nutritional food components, were used in experiments
on feeding, egg production, hatching success, pellet production, and behavior of three common planktonic copepods: Acartia tonsa, Pseudocalanus elongatus, and Temora longicornis. The three different diatom strains (9B, 1G, and 7J) induced widely different effects on Acartia tonsa physiology, and the 9B strain induced different effects for the three copepods. In contrast, different strains induced no
or small alterations in the distribution, swimming behavior, and turning frequency of the copepods. 22:6(n-3) fatty acid (DHA)
and sterol content of the diet typically showed a positive effect on either egg production (A. tonsa) or hatching success (P. elongatus), while other measured compounds (PUA, other long-chain polyunsaturated fatty acids) of the algae had no obvious effects.
Our results demonstrate that differences between strains of a given diatom species can generate effects on copepod physiology,
which are as large as those induced by different algae species or groups. This emphasizes the need to identify the specific
characteristics of local diatoms together with the interacting effects of different mineral, biochemical, and toxic compounds
and their potential implications on different copepod species. 相似文献
205.
Sally Ann Sims Jennifer R. Seavey Charles G. Curtin 《Journal of Coastal Conservation》2013,17(3):339-350
Accelerated sea level rise (slr) is expected to transform vulnerable Atlantic coastal habitats in the United States during this century. Low-elevation sandy beaches, important nesting habitat for the continued recovery of the federally threatened piping plover (Charadrius melodus) in Rhode Island, are especially vulnerable. These beaches, under a mix of private and public ownership, exist in a heterogeneous landscape of dunes, rocky headlands, salt ponds, and heavily developed areas. Understanding the extent to which piping plover nesting beaches can retreat landward under projected slr is important for prioritizing future conservation actions across multiple jurisdictions. This research examines habitat change in response to slr (0.5, 1.0, and 1.5 m) under stationary and migration beach responses and whether development blocks habitat migration for five productive piping plover nesting beaches. We found that under the stationary habitat model, all beaches lose area under all slr scenarios. For the habitat migration model, future habitat availability differs by beach depending on elevation, landward topography, and presence of development. However, across the majority of beach area, piping plover habitat will be able to migrate landward if unconstrained by future development. A coalition of public and private stakeholders already supports management efforts to help ensure plover population recovery in the area. With emerging habitat change prediction tools, these stakeholders and other partners can engage in innovative, local-level planning needed to protect wildlife habitat and commercial, residential, and infrastructure assets from sea level rise. 相似文献
206.
Gregory W Whitledge Charles F Rabeni Gust Annis Scott P Sowa 《Ecological applications》2006,16(4):1461-1473
Moderation of stream temperatures by riparian shading and groundwater are known to promote growth and survival of salmonid fishes, but effects of riparian shade and groundwater on to be growth of warmwater stream fishes are poorly understood or assumed to be negligible. We used stream temperature models to relate shading from riparian vegetation and groundwater inflow to summer water temperatures in Missouri Ozark streams and evaluated effects of summer water temperatures on smallmouth bass, Micropterus dolomieu, growth using a bioenergetics model. Bioenergetics model simulations revealed that adult smallmouth bass in non-spring-fed streams have lower growth potential during summer than fish in spring-fed streams, are subject to mass loss when stream temperatures exceed 27 degrees C, and will likely exhibit greater interannual variation in growth during summer if all growth-influencing factors, other than temperature, are identical between the two stream types. Temperature models indicated that increased riparian shading will expand the longitudinal extent of thermal habitat capable of supporting adult smallmouth bass growth in spring-fed stream reaches when mean daily air temperatures exceed 27 degrees C. Optimum growth temperature (22 degrees C) will be present only in spring-fed streams under these conditions. Potential for increasing shade through riparian restoration is greatest for streams <5 m wide and along north-south reaches of larger streams. However, temperature models also indicated that restoring riparian shading to maximum levels throughout a watershed would increase the total stream mileage capable of supporting positive growth of adult smallmouth bass by only 1-6% when air temperatures are at or near average summer maxima; increases in suitable thermal habitat would be greatest in watersheds with higher spring densities. Riparian management for maintenance or restoration of the thermal habitat of adult smallmouth bass during summer should be focused in areas strongly influenced by groundwater. Restoring riparian shading along spring-fed warmwater streams will likely benefit adult smallmouth bass growth and may ultimately influence population sizes. 相似文献
207.
Olivier Roux Charles Gers Josèphe Nathan Tene-Ghomsi Laurence Arvanitakis Dominique Bordat Luc Legal 《Chemoecology》2007,17(1):13-18
Summary. Cotesia plutellae is a specialist parasitoid of Plutella xylostella. This specificity is potentially under the control of several factors before and after oviposition. Thereby, the stimuli
that lead female parasitoids to host locations and to oviposition, might be at the basis of the specificity. We explore here
the response of C. plutellae females exposed to host cuticular lipids. A total cuticular lipid extract of host caterpillars was fractionated into a hydrocarbon
fraction and a non-hydrocarbon fraction. Neither fraction alone had any effect on oviposition behaviour in C. plutellae but the hydrocarbon fraction alone did seem to have a positive effect on the rate of antennal contact by the females. To
induce oviposition behaviour, both fractions were necessary and reflect cooperation between at least one compound in each
fraction. Identification of cuticular lipids shows that hydrocarbons were dominant (77%). Non-hydrocarbon compounds were mainly
represented by 15-nonacosanone (18% of the total lipid extract). This ketone is rare in insect cuticle lipids and is thought
to originate from the cabbage epicuticle where it is dominant with n-C29 and 14- and 15-nonacosanol also found among the cuticular lipids of the host caterpillar. 相似文献
208.
Steven C. Schimmel Sandra J. Benyi Charles J. Strobel 《Environmental monitoring and assessment》1999,56(1):27-49
Data from the Environmental Protection Agency's (EPA) Environmental Monitoring and Assessment Program (EMAP) from 1990 to 1993 were used to assess the condition of the Long Island Sound (LIS) estuary. Ambient water, sediment and biota were collected during the summer months from 53 LIS stations using an unbiased sampling design. The design consists of two LIS subunits, LIS proper, and small estuaries (<2.6 km2) at the margins of the Sound. Selected indicators of condition included: benthic species composition, abundance and biomass; fish species composition and gross external pathology; sediment physical and chemical characterization and sediment toxicity; and water clarity and quality. Results of the four-year sampling indicated that 28(±11)% of the areal extent of LIS proper had a benthic index < zero (impacted) and 51(±12)% of the area of small estuaries was impacted. Analysis of the results of other indicators also shows that small estuaries were particularly affected. For example, 42(±10)% of the areal extent of small estuaries exhibited sediment toxicity, and significant chemical contamination was evident in 22% of the area of small estuaries. Low dissolved oxygen (D.O.) concentrations (<5 ppm), however, appeared to affect only the deeper open waters of western LIS. Approximately 48(±12)% of the areal extent of LIS proper documented exposure to at least moderate D.O. stress (<5 ppm). The overall results of this monitoring study indicate that significant anthropogenic impacts have occurred in LIS and that if remediation was to take place, specific localized sediment problems would need attention. Point source and non-point source nutrient inputs to the Sound, which are believed to be the primary causative factor for the observed hypoxic conditions, would also need attention. 相似文献
209.
Charles S. Tapiero 《Environmental Modeling and Assessment》2005,9(4):201-206
Conclusion In this paper we have considered a specific environmental game emphasizing both control-prevention efforts and the propensity to pollute by a firm which adopts a given pollution abatement technology. A random payoff game was constructed and solved under a risk neutral assumption and quadratic utilities for both the firm and the environmental controller. The game thus defined, provides a wide range of interpretations and potential approaches for selecting a control-inspection policies to prevent environmental risks. There are of course many facets to this problem, which could be considered and have not been considered in sufficient depth. For example, more complex control mechanisms and liabilities, the effects of insurance and risk sharing, the application of cooperative efforts and subvention of pollution abatement investments (through tax incentives and their like), etc. have not been considered [5,7]. These are topics for further research. The basic presumption of this paper is that it is very difficult to fully enforce pollution prevention by firms, as a result, some controls are needed to ensure that firms be controlled so that appropriate efforts are carried. 相似文献
210.
The present study tested the utilization of dead microbial biomass by two benthic deposit-feeders:Abra alba (Wood) (Mollusca: Bivalvia) andEupolymnia nebulosa (Montagu) (Annelida: Polychaeta). Clams were collected in the Canet lagoon during spring 1989. Worms were collected in the Port-Vendres harbour during spring 1989. The14C-labelled (glutamic acid, 24 h) sediment used during the study was sterilized with 1% chloroform, washed with sterile seawater, and dried (60°C; 48 h). This sterilisation procedure, called fumigation is the least harmful to the sediment (Novitsky 1986). Both clams and worms were incubated in the presence of the fumigated sediment for 5, 10, 20, and 50 h. At the end of each experiment we recorded the radioactivity in four compartments: (1) sediment, (2) dissolved organic matter (DOM), (3) CO2, and (4) animals. The radioactivity of the sediment was subdivided into five fractions: (i) soluble in 2N HCl, (ii) soluble in hot 5% trichloroacetic acid (TCA), (iii) soluble in 1N NaOH, (iv) soluble in hot 6N HCl, (v) residual (after combustion in a Leco carbon analyser). In the first set of experiments, after 20 h of incubation, 5.4 and 4.7% of the total radioactivity was taken up by clams and worms, respectively. However, a model revealed that this uptake could have been correlated with the release of radiolabelled DOM (33% of total radioactivity during the first 5 h). In order to test this assumption, we used the same protocol with three additional washes of the fumigated sediment. This resulted in a significantly lower uptake by the clams (1.9% of the total radioactivity byt = 50 h), whereas the worms exhibited an uptake similar to that in the initial experiment (5.1% of total radioactivity byt = 50 h). These results underline the importance of considering interactions with DOM when applying radiotracer techniques to the study of benthic food chains. The average ingestion rates of fumigated sediment byA. alba andE. nebulosa were 5.2 10–2 mg sediment dry wt mg–1 clam h–1 and 3.5 10–2 mg sediment dry wt mg–1 worm h–1, respectively, which is comparable to previous data reported for other deposit-feeding bivalves and polychaetes feeding on natural sediment or detritus. The low radioactivity recorded for CO2 together with the similarity of the changes in the partitioning of the radioactivity within the sediment between control experiments and experiments carried out in the presence of clams or worms suggest low assimilation efficiencies. Therefore, the present study supports the fact that dead microbial biomass does not constitute an important food source for benthic deposit-feeders. 相似文献