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61.
Barriers to adaptation have become an important concept in scientific and political discussions in the governance of climate change adaptation. Over the past years, these discussions have been dominated by one analytical lens in examining barriers and proposing ways to overcome them: the problem solving lens. In this paper, we aim to demonstrate theoretically and empirically that the choice of analytical lens influences how barriers to adaptation are constructed and the intervention strategies proposed. Drawing from recent governance literature, we explore the rationale of three dominant philosophies in the study of governance: the optimist, the realist, and the pessimist philosophy. Next, we demonstrate how these philosophies are operationalized and guide scientific inquiry on barriers to adaptation through four empirically rooted analytical lenses: i) governance as problem solving, ii) governance as competing values and interests, iii) governance as institutional interaction, and iv) governance as dealing with structural constraints. We investigate the Dutch government’s Spatial Adaptation to Climate Change programme through each of the four lenses. We discuss how each analytical lens frames barriers in a specific way, identifies different causes of barriers, leads to competing interpretations of key events, and presents other types of interventions to overcome barriers. We conclude that it is necessary to increase analytical variety in order to critically engage in theoretical debates about barriers and to empower policy practitioners in their search for successful intervention strategies to implement adaptation measures.  相似文献   
62.
Recently, fly ash deposits have been revealed as a secondary refuge of critically endangered arthropods specialised on aeolian sands in Central Europe. Simultaneously, these anthropogenic habitats are well known for their negative impact on human health and the surrounding environment. The overwhelming majority of these risks are caused by wind erosion, the substantial decreasing of which is thus necessary. But, any effects of anti-dust treatments on endangered arthropods have never been studied. We surveyed communities of five arthropod groups (wild bees and wasps, leafhoppers, spiders, hoverflies and orthopteroid insects) colonising three fly ash deposits in the western Czech Republic. We focused on two different anti-dust treatments (~70 and 100 % cover of fly ash by barren soil) and their comparison with a control of bare fly ash. Altogether, we recorded 495 species, including 132 nationally threatened species (eight of them were considered to be extinct in the country) and/or 30 species strictly specialised to drift sands. Bees and wasps and leafhoppers contained the overwhelming majority of species of the highest conservation interest; a few other important records were also in spiders and orthopteroids. Total soil cover depleted the unique environment of fly ash and thus destroyed the high conservation potential of the deposits. On the other hand, partial coverage (with ~30 % of bare fly ash) still offered habitats for many of the most threatened species, as we showed by both regression and multivariate analyses, with a decrease of wind erosion. This topic still needs much more research interest, but we consider mosaic-like preservation of smaller spots of fly ash as one of the possible compromises between biodiversity and human health.  相似文献   
63.
Climate warming is occurring in concert with other anthropogenic changes to ecosystems. However, it is unknown whether and how warming alters the importance of top-down vs. bottom-up control over community productivity and variability. We performed a 16-month factorial experimental manipulation of warming, nutrient enrichment, and predator presence in replicated freshwater pond mesocosms to test their independent and interactive impacts. Warming strengthened trophic cascades from fish to primary producers, and it decreased the impact of eutrophication on the mean and temporal variation of phytoplankton biomass. These impacts varied seasonally, with higher temperatures leading to stronger trophic cascades in winter and weaker algae blooms under eutrophication in summer. Our results suggest that higher temperatures may shift the control of primary production in freshwater ponds toward stronger top-down and weaker bottom-up effects. The dampened temporal variability of algal biomass under eutrophication at higher temperatures suggests that warming may stabilize some ecosystem processes.  相似文献   
64.
The aim of this paper is to explore the issue of problem definition in coastal (zone) management, with particular emphasis on social and institutional aspects. Do the existing scientific theories provide the necessary tools for open formulation of questions or problem definition, without preconceived ideas? Or are they rigid frameworks, which lead our curiosity along well-paved trails to predetermined results? Formulation of the right questions is probably the most important step in arriving at relevant answers.  相似文献   
65.
Massive cyanobacterial water blooms and production of toxins (cyanotoxins) have become a worldwide problem. In this report, we present results of cyanotoxins analyses (peptide microcystins, alkaloid cylindrospermopsin) in the Czech Republic reservoirs using HPLC-PDA and ELISA. Our study suggests the occurrence of cylindrospermopsin in the Czech Republic for the first time (particularly, in water blooms containing Aphanizomenon klebahnii). We also discuss human health risks associated with microcystins in relation to the drinking water guideline value of 1.0 μg/l as recommended by the World Health Organization.  相似文献   
66.
Species diversity modulates predation   总被引:3,自引:0,他引:3  
Kratina P  Vos M  Anholt BR 《Ecology》2007,88(8):1917-1923
Predation occurs in a context defined by both prey and non-prey species. At present it is largely unknown how species diversity in general, and species that are not included in a predator's diet in particular, modify predator-prey interactions. Therefore we studied how both the density and diversity of non-prey species modified predation rates in experimental microcosms. We found that even a low density of a single nonprey species depressed the asymptote of a predator's functional response. Increases in the density and diversity of non-prey species further reduced predation rates to very low levels. Controls showed that this diversity effect was not due to the identity of any of the non-prey species. Our results establish that both the density and diversity of species outside a predator's diet can significantly weaken the strength of predator-prey interactions. These results have major implications for ecological theory on species interactions in simple vs. complex communities. We discuss our findings in terms of the relationship between diversity and stability.  相似文献   
67.
Environmental Science and Pollution Research - The Moravian-Silesian region of the Czech Republic with its capital city Ostrava is a European air pollution hot spot for airborne particulate matter...  相似文献   
68.
69.
Environmental Science and Pollution Research - Willows (Salix spp.) are considered to be effective for the phytoremediation of trace elements from contaminated soils, but their efficiency is...  相似文献   
70.
Testing biodegradability of plastics under varied conditions of the environment as well as under laboratory conditions in accordance with valid international standards is very laborious, lengthy and often also economically demanding. For this reason, applicability was verified of gas chromatography to analyze gaseous phase when investigating the biodegradation course of plastics in an aqueous environment as an alternative to customary employed methods. A mathematical model of acid–basic CO2 equilibrium in a gas–liquid system was worked out, enabling to determine quantity of produced CO2 through chromatographic analysis of gaseous phase, in dependence on ratio of liquid and gas phase volumes (V l/V g) and on actual pH of liquid phase. Experimental conditions for organizing the tests were optimized. A ratio that proved suitable was V l/V g ≅ 0.1 at pH ≈ 7.1 of liquid phase. Under these test conditions, biodegradability of model samples, PHB, Gellan gum and Xanthan gum, was explored; course of biodegradation was studied through produced CO2 (values ) determined by analyzing gaseous phase through gas chromatography on the one hand, and through customary “titration” procedure on the other. With water-soluble polymers, the decrement in dissolved organic carbon (values D DOC) was also studied. Difference between values does not exceed 5%. The procedures in question are alternative “substituting” procedures for observing course of aerobic biodegradation of substances in an aqueous environment.  相似文献   
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