Late and middle Pleistocene ungulates dietary diversity in Western Europe indicate variations of Neanderthal paleoenvironments through time and space     

Florent Rivals  Ellen Schulz  Thomas M. Kaiser 《Quaternary Science Reviews》2009,28(27-28):3388-3400

Mesowear and microwear on enamel from 763 teeth of middle and late Pleistocene ungulates were analysed to infer the potential of dental wear analysis of faunal remains as a paleoenvironmental and paleoclimatic proxy in relation to climatic changes and diversity of vegetation available in the environment. Fossil localities including levels belonging to two glacial and two interglacial stages were selected in Germany, France, and Spain. At a temporal scale, results indicate that the dietary diversity in ungulates is higher during interglacial phases (MIS 5 and 3) than during pleniglacial phases (MIS 8 and 4). Dietary diversity is concluded to be related to climate-driven vegetation changes which during interglacials lead to increased variety of potential food items available to ungulates. At the geographical scale, during interglacials, changes in diet composition are evident along geographical gradients. The corresponding dietary gradients are proposed to be related to climate and vegetation gradients reflecting more arid climates in the Mediterranean area compared to North-Western Europe. Species consistently represented at all localities investigated are Cervus elaphus (Cervidae, Artiodactyla) and Equus ferus (Equidae, Perissodactyla). C. elaphus populations are found to consistently have less abrasive diets than E. ferus populations but dietary traits of both species varied largely, revealing a significant plasticity in the feeding adaptation of both species. Those traits are concluded to be related to differences in vegetation structure at each locality and complement the evidence that ungulates have broader dietary habits than what is usually assumed.  相似文献   

Climate policy at the local level: Insights from California     

Louise W. Bedsworth  Ellen Hanak 《Global Environmental Change》2013,23(3):664-677

Local governments in the United States have been hotbeds of climate change activity. Recently, states have sought to incorporate these primarily voluntary actions into broader climate change mitigation programs. Using the example of California, a national leader in U.S. climate policy, this article examines the scope for effectiveness of local climate action and assesses factors related to adoption of local climate policies. The analysis draws on two original surveys of city and county governments, designed to learn about adoption of comprehensive policy tools (emission inventories and climate action plans) and programs in specific areas (energy, water, land use, transportation). Adoption rates are fairly high and growing; by mid 2010 roughly 70% of all jurisdictions were already engaged or planning to engage in comprehensive climate actions, up from roughly 50% in 2008. The adoption of specific programs varies with the degree of local government authority in different sectors, and is generally higher for programs targeting municipal facilities and operations than those targeting residents and businesses. Population size, household income, and strong support from local leaders and the public are all associated with higher rates of adoption, particularly for comprehensive actions. Partisan attitudes are more important for comprehensive actions than for programs in specific areas such as energy efficiency and renewable energy, mirroring the findings of state and national public opinion surveys, which find broader support for actions like clean energy than for explicit climate change-oriented actions. Qualitative analysis reveals additional keys to success, including partnering with other local governments and private organizations and leveraging cost savings and other potential co-benefits of action. As states move to incorporate local actions into broader plans, mandates will also play an increasing role in setting a floor for local efforts.  相似文献   

It is a moral issue: The relationship between environmental self-identity,obligation-based intrinsic motivation and pro-environmental behaviour     

Ellen van der Werff  Linda Steg  Kees Keizer 《Global Environmental Change》2013,23(5):1258-1265

In order to effectively mitigate climate change, people need to adopt environmentally-friendly actions. We argue that some people act in an environmentally-friendly manner without external incentives to do so, but rather because they are intrinsically motivated to do so. There is some initial evidence to suggest that this is particularly likely for people with a strong environmental self-identity. However, not much is known about how environmental self-identity influences pro-environmental actions. In this research, we aimed to test whether, and if so, via which process environmental self-identity is related to environmentally-friendly behaviour. We conducted three studies to test our hypotheses. In the first study, our hypotheses were confirmed in a sample of the general population using a correlational design. In the second study, we replicated our findings with a different indicator of moral obligation and with a different dependent variable. In the third study, we tested our model in an experimental design. Again, we found support for our hypotheses that environmental self-identity is related to one's obligation-based intrinsic motivation (that is, feelings of moral obligation) to act pro-environmentally, which in turn affects pro-environmental actions. As expected, the obligation-based intrinsic motivation mediates the relationship between environmental self-identity and environmentally-friendly behaviour. Our findings suggest that strengthening environmental self-identity may be a cost-effective way to promote pro-environmental actions, as people with a strong environmental self-identity are likely to act in an environmentally-friendly manner without an external incentive to do so.  相似文献   

CAREGIVING ENVIRONMENTS AND ELDERLY RESIDENTIAL MOBILITY*     

Judith W. Meyer  Ellen K. Cromley 《The Professional geographer》1989,41(4):440-450

Formal and informal caregiving, an aspect of the environment of older elderly people, helps differentiate their residential mobility decisions from those of younger people. A recently proposed developmental model of elderly mobility that focuses on caregiving and health is evaluated through the literature and by a survey of recently hospitalized individuals over 75 years old. The model is expanded to include an anticipatory stage of mobility during which older Americans consciously try to organize their environments.  相似文献   

Biotransformation of pesticides in saturated-zone materials     

Blythe L. Hoyle  Ellen L. Arthur 《Hydrogeology Journal》2000,8(1):89-103

Many studies have been conducted to evaluate pesticide contamination of groundwater in the United States, but investigations of pesticide biotransformation in saturated zones are much less numerous than in surface soils. Because results of studies using soils are not directly applicable to the subsurface, the purpose of this paper is to illustrate examples of pesticide biotransformation in saturated-zone materials. Although it must be considered with caution, the US Environmental Protection Agency's (EPA) "Pesticides in Ground Water Database" was used to focus the discussion on the biotransformation potential of dibromoethane (EDB), atrazine, acetanilide herbicides, and aldicarb, all of which have been detected in groundwater in the United States. Results of more than two dozen studies indicate that a biotransformation potential for these pesticides exists in saturated-zone materials, although for any given pesticide substantial differences in biotransformation occurred. These variations were due both to differences in experimental methods and to heterogeneities in the subsurface materials under investigation. However, because biotransformation mechanisms were not well investigated, it is generally not possible to extrapolate predictions of biotransformation potential beyond the specific sites investigated. These results highlight the need to better understand microbial genetic regulation of biotransformation processes so that genetic information may be effectively incorporated into future investigations of biotransformation potential in the subsurface. Résumé De nombreuses études ont été réalisées pour évaluer le degré de pollution des aquifères par les pesticides aux États-Unis, mais les recherches concernant la biotransformation des pesticides dans les eaux souterraines sont beaucoup moins nombreuses que dans les sols. Du fait que les résultats des études concernant les sols ne sont pas directement applicables au milieu souterrain, le propos de cet article est d'illustrer par des exemples la biotransformation des pesticides dans les nappes. Bien qu'il faille la considérer avec précaution, la base de données sur les pesticides dans les eaux souterraines de l'Agence américaine pour la protection de l'environnement a été utilisée pour centrer la discussion sur le potentiel de biotransformation du dibromoéthane (EDB), de l'atrazine, des désherbants acétanildés et de l'aldicarb, qui tous ont été détectés dans les nappes des États-Unis. Les résultats de plus de deux douzaines d'études indiquent qu'il existe un potentiel de biotransformation de ces pesticides dans les nappes, bien qu'entre chacun de ces pesticides il existe des différences très nettes dans la biotransformation. Ces variations sont en fait dues à la fois à des différences dans les méthodes expérimentales et dans les hétérogénéités dans les matériaux étudiés. Cependant, parce que les mécanismes de la biotransformation ne sont pas bien étudiés, il est en général impossible d'extrapoler les prédictions du potentiel de biotransformation à des sites d'étude spécifiques. Ces résultats soulignent la nécessité de mieux comprendre la régulation génétique microbienne des processus de biotransformation, pour que l'information génétique puisse être efficacement prise en compte dans les futures recherches sur le potentiel de biotransformation dans le sous-sol. Resumen Se han llevado a cabo un gran número de estudios para evaluar la contaminación por pesticidas en los acuíferos de los Estados Unidos de América. Sin embargo, las investigaciones sobre biotransformación de pesticidas en la zona saturada son mucho menos numerosas que en suelos. Como los resultados obtenidos en suelos no son directamente transladables a la zona saturada, el objetivo de este artículo es mostrar ejemplos de biotransformación de pesticidas en la zona saturada. Aunque debe tomarse con cautela, la base de datos "Pesticides in Ground Water Database (Base de Datos de Pesticidas en Aguas Subterráneas)" perteneciente a la US EPA (Agencia de Protección Ambiental de los EEUU) se usó para centrar la discusión en la biotransformación potencial de diversos compuestos orgánicos detectados en diversos acuíferos de los EEUU. Los resultados de más de dos docenas de estudios indican que la biotransformación potencial de estos pesticidas en la zona saturada es posible, aunque para un pesticida dado pueden presentarse grandes diferencias, debidas tanto a diferencias en los métodos experimentales como a la heterogeneidad de los materiales. Sin embargo, no es posible en general extrapolar las predicciones de biotransformación potencial más allá de las zonas específicas estudiadas, al no haberse investigado en detalle sus mecanismos. Los resultados del estudio indican la necesidad de entender mejor la regulación genética de los procesos de biotransformación, para que la información genética pueda incorporarse de manera efectiva en las investigaciones futuras de biotransformación potencial en acuíferos.  相似文献   

Mountain river channels   总被引：1，自引：0，他引：1  

Anne Chin  Ellen Wohl 《Geomorphology》2007,83(3-4):197

  相似文献   

Environmental controls on bacterial tetraether membrane lipid distribution in soils   总被引：2，自引：0，他引：2  

Johan W.H. Weijers  Stefan Schouten  Jurgen C. van den Donker  Ellen C. Hopmans  Jaap S. Sinninghe Damsté 《Geochimica et cosmochimica acta》2007,71(3):703-713

Over the last years a novel group of branched glycerol dialkyl glycerol tetraether (GDGT) membrane lipids has been discovered in peat bogs and soils. They consist of components with 4-6 methyl groups attached to the n-alkyl chains and 0 to 2 cyclopentyl moieties in the alkyl chain. These branched membrane lipids are produced by an as yet unknown group of anaerobic soil bacteria. In this study we analysed the branched membrane lipid content of 134 soil samples from 90 globally distributed locations to study the environmental factors controlling the relative distribution of the different branched GDGT isomers. Our results show that the relative amount of cyclopentyl moieties, expressed in the cyclisation ratio of branched tetraethers (CBT), is primarily related to the pH of the soil (R² = 0.70) and not to temperature (R² = 0.03). The relative amount of methyl branches, expressed in the methylation index of branched tetraethers (MBT), is positively correlated with the annual mean air temperature (MAT) (R² = 0.62) and, to a lesser extent, negatively correlated with the pH of the soil (R² = 0.37). If both parameters are combined, however, it appears that the variation in the MBT is largely explained by both MAT and pH (R² = 0.82). These results suggest that the relative distribution of soil-derived GDGT membrane lipids can be used in palaeoenvironmental studies to estimate past annual MAT and soil pH.  相似文献   

Assessing morphological degradation in running waters using Blackfly communities (Diptera, Simuliidae): Can habitat quality be predicted from land use?     

Melanie Lautenschlger  Ellen Kiel 《Limnologica》2005,35(4):262-273

Based on benthic macroinvertebrate samples from 57 sites of streams in the European Central Highlands (Ecoregion 9; Illies (1978). Limnofauna Europaea, Stuttgart), the composition and the abundance of Simuliid species were analysed in relation to hydromorphological and land use parameters. Sampling sites were located at two stream types differing in catchment geology, stream morphology and channel width. Land use data were taken from the official German information system for cartography and topography (ATKIS) and the German River Habitat Survey. Land use categories suitable to describe the sampling sites were ‘agricultural land’, ‘urban’ and near-natural areas. Hydromorphological parameters of the sites were recorded using the AQEM site protocol (AQEM Consortium (2002). Manual for the application of the AQEM system. A comprehensive method to assess European streams using benthic macroinvertebrates, developed for the purpose of the Water Framework Directive. EVK1-CT1999-00027, Version 1.0. Available via the Internet from www.aqem.de). Relevant parameters controlling Simuliid distribution in streams were the mineral substrates and the biotic microhabitats. Blackfly larvae and pupae were sampled at each site for 15 min. Statistical analysis was performed by CANOCO^® (Ter Braak & Smilauer (1997). CANOCO Version 4.5. Biometrics Plant Research International, Wageningen, The Netherlands) using redundancy analysis (RDA).

Our results show a stream type-specific composition of the Blackfly fauna. The analyses reveal sensitivity of the Simuliid species to morphological degradation, which is indicated by the shift in the longitudinal zonation of the Simuliid communities. Especially, Prosimulium hirtipes (Fries, 1824) and Simulium argyreatum Meigen, 1838 are typical representatives of headwater streams. While they seem to indicate undisturbed conditions of this stream type and react sensitively to the degradation of stream habitats, Simulium ornatum Meigen, 1818 and Simulium equinum (Linnaeus, 1758) are more tolerant to stream degradation.

On catchment scale, ‘% natural forest’ and ‘% agricultural land use’ illustrate the degree of degradation of the two selected stream types. ‘Average stream depth’ and ‘relation riffles/pools’ account for hydromorphological degradation reflected by Simuliid species on the smaller reach scale. The analysis of habitat quality revealed that ‘% woody debris’ represents an important parameter of morphological degradation reflected by the Blackfly community.  相似文献   

CLIMATE CHANGE, AGRICULTURE AND WETLANDS IN EASTERN EUROPE: VULNERABILITY, ADAPTATION AND POLICY   总被引：6，自引：1，他引：6  

Ellen KRACAUER Hartig  Ognyan Grozev  Cynthia Rosenzweig 《Climatic change》1997,36(1-2):107-121

Naturally-occurring wetlands perform such functions as flood control, pollution filtration, nutrient recycling, sediment accretion, groundwater recharge and water supply, erosion control, and plant and wildlife preservation. A large concentration of wetlands is located in Eastern Europe. A significant amount of Eastern European wetlands has been converted to agricultural use in the past, and remaining wetlands are subject to agricultural drainage. Drained wetlands are used as prime agriculture lands for a variety of food crops. Other agricultural uses of wetlands range from growing Phragmites australis (common reed) for thatch and livestock feed, to collecting peat for heating and cooking fuel. Altered hydrologic regimes due to global climate change could further exacerbate encroachment of agricultural land use into wetlands. The vulnerability and adaptation studies of the U.S. Country Studies Program are used to analyze where climate change impacts to agriculture may likewise impact wetland areas. Scenarios indicate higher temperatures and greater evapotranspiration altering the hydrologic regime such that freshwater wetlands are potentially vulnerable in Bulgaria, Czech Republic, and Russia, and that coastal wetlands are at risk in Estonia. Runoff is identified as a key hydrological parameter affecting wetland function. Since wetland losses may increase as a result of climate-change-induced impacts to agriculture, precautionary management options are reviewed, such as establishing buffer areas, promoting sustainable uses of wetlands, and restoration of farmed or mined wetland areas. These options may reduce the extent of negative agricultural impacts on wetlands due to global climate change.  相似文献   

Multi-Objective Analysis of School District Regionalization Alternatives in Connecticut*     

Scott M. November  Robert G. Cromley  Ellen K. Cromley 《The Professional geographer》1996,48(1):1-14

This paper demonstrates the utility of multi-objective programming techniques as an aid in educational planning and the limitations to the achievement of any educational objective given the spatial distribution of existing disparities. A case study of Connecticut is used to examine alternative scenarios for the implementation of interdistrict responses to a number of issues facing the state's public education system. A mixed-integer, goal programming model is formulated where the goal constraints are to minimize disparities in: (1) minority enrollments, (2) grand-list/student ratios, (3) student-teacher ratios, and (4) overall enrollment. Results show that the traditional distance-minimizing or transportation-minimizing objectives are in conflict with all other aims of equity and quality of educational opportunities. The geographic distribution of minority students and grand-list property values also limited the reduction of statewide disparities in these goals.  相似文献