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111.
The impact of ancient fertilization practices on the biogeochemistry of arable soils on the remote Scottish island of Hirta, St Kilda was investigated. The island was relatively unusual in that the inhabitants exploited seabird colonies for food, enabling high population densities to be sustained on a limited, and naturally poor, soil resource. A few other Scottish islands, the Faeroes and some Icelandic Islands, had similar cultural dependence on seabirds. Fertilization with human and animal waste streams (mainly peat ash and bird carcases) on Hirta over millennia has led to over-deepened, nutrient-rich soils (plaggen). This project set out to examine if this high rate of fertilization had adversely impacted the soil, and if so, to determine which waste streams were responsible. Arable soils were considerably elevated in Pb and Zn compared to non-arable soils. Using Pb isotope signatures and analysis of the waste streams, it was determined that this pollution came from peat and turf ash (Pb and Zn) and from bird carcases (Zn). This was also confirmed by 13C and 15N analysis of the profiles which showed that soil organic matter was highly enriched in marine-derived C and N compared to non-arable soils. The pollution of such a remote island may be typical of other ‘bird culture’ islands, and peat ash contamination of marginal arable soils at high latitudes may be widespread in terms of geographical area, but less intense at specific locations due to lower population densities than on Hirta.  相似文献   
112.
Engaging with dialogue concerning the relevance and applicability of social capital to a model of sustainable community development, we illustrate an in-depth case of a community experiencing an ideological clash with the dominant politico-societal structures. We argue that while the exclusivity of bonding social capital has been described as the 'dark side', it may be essential for progressive sustainable community development (PSCD). When faced with a development threat, such bonds are essential for building links, bridges and solidarity, enabling cultural reproduction and promoting environmental protection for sustainability.  相似文献   
113.
The European Commission (EC) has recognized a need for strengthening innovation of environmental technologies in order to increase competitiveness of European technologies on a global market and to achieve a more sustainable development in Europe. In the area of soil and groundwater remediation, innovative technologies are principally available and have proven applicability and performance on demonstration scales, but market uptake is disappointing. Consequently, initiatives have been launched in order to promote application of these technologies and to investigate on the harmonization of applications. The European Co‐ordination Action for Demonstration of Efficient Soil and Groundwater Remediation (EURODEMO), an EC‐funded project, is one strategic initiative for supporting these goals. This article summarizes results obtained so far regarding the investigation of the European situation and some undertaken and envisaged measures to achieve better market uptake. The results of this research project may serve as prerequisites for a European Environmental Technologies Verification (ETV) process. © 2006 Wiley Periodicals, Inc.  相似文献   
114.
Edwards AM 《Ecology》2011,92(6):1247-1257
A surprisingly diverse variety of foragers have previously been concluded to exhibit movement patterns known as Lévy flights, a special type of random walk. These foragers range in size from microzooplankton in experiments to fishermen in the Pacific Ocean and the North Sea. The Lévy flight conclusion implies that all the foragers have similar scale-free movement patterns that can be described by a single dimensionless parameter, the exponent micro of a power-law (Pareto) distribution. However, the previous conclusions have been made using methods that have since been shown to be problematic: inaccurate techniques were used to estimate micro, and the power-law distribution was usually assumed to hold without testing any alternative hypotheses. Therefore, I address the open question of whether the previous data still support the Lévy flight hypothesis, and thus determine whether Lévy flights really are so ubiquitous in ecology. I present a comprehensive reanalysis of 17 data sets from seven previous studies for which Lévy flight behavior had been concluded, covering marine, terrestrial, and experimental systems from four continents. I use the modern likelihood and Akaike weights approach to test whether simple alternative models are more supported by the data than Lévy flights. The previously estimated values of the power-law exponent micro do not match those calculated here using the accurate likelihood approach, and almost all of them lie outside of the likelihood-based 95% confidence intervals. Furthermore, the original power-law Lévy flight model is overwhelmingly rejected for 16 out of the 17 data sets when tested against three other simple models. For one data set, the data are consistent with coming from a bounded power-law distribution (a truncated Lévy flight). For three other data sets, an exponential distribution corresponding to a simple Poisson process is suitable. Thus, Lévy flight movement patterns are not the common phenomena that was once thought, and are not suitable for use as ecosystem indicators for fisheries management, as has been proposed.  相似文献   
115.
ABSTRACT: A pumping test on a phreatic glacial till aquifer was performed near Ames, Iowa, in November 1990. The head in a horizontal well was pumped down rapidly and then held constant for the duration of the 30-hour test. Throughout the test, the flow rate at the pumped well and the head at an adjacent vertical observation well were recorded. The pumping test data were used to determine the hydraulic conductivity and specific yield of the aquifer. The results indicate a hydraulic conductivity of 2.23 × 10?5 cm/s and a representative specific yield of 0.03. Hydraulic conductivity was calculated by a simple integration of Darcy's Law after extrapolating the data to steady state. Specific yield was determined by use of several methods from the literature and a new method proposed by the author. The results show that specific yield increases with time, and that each method is within an order of magnitude of the others.  相似文献   
116.
117.
Edwards KF  Stachowicz JJ 《Ecology》2010,91(11):3146-3152
For competing species limited by one or few resources, diversity is thought to be maintained by trade-offs that allow niche differentiation without resource partitioning. However, few studies have quantified multiple key traits for each species in a guild and shown that trade-offs among these traits apply across the guild. Here we document strong bivariate and multivariate relationships among growth rate, fecundity, longevity, and overgrowth ability for six co-occurring colonial invertebrates. We find that all four of these traits are constrained to a single "fast-slow" niche axis that mechanistically relates life history variation to a colonization-competition trade-off. The location of species on this axis strongly predicts the timing of their peak abundance during succession. We also find that species closer to each other on the fast-slow axis are more likely to differ in reproductive phenology, suggesting a secondary dimension of niche differentiation for otherwise similar species.  相似文献   
118.
119.
Agricultural activities are one of the major drivers of increased nutrient levels such as nitrogen (N) and phosphorus (P) to both terrestrial and aquatic ecosystems. Elevated nutrient concentrations are associated with degraded water quality that can result in potential impacts for human health and the environment. A recent European study has identified elevated concentrations of N and P for many European river monitoring stations. In many cases the management of N and P has been considered separately here we address the multi-dimensional issue of water quality where the simultaneous management and control of both N and P is considered desirable. Using an integrated modelling approach various nutrient management scenarios are examined. It is found that although the control of N and P involve different farm adjustments and induce different land use changes there is a certain degree of complementarity between these two nutrient controls. The policy implication of ignoring such complementarity is that the appropriate environmental taxes to control the required nutrient losses are overestimated, resulting in unnecessary welfare losses to the society.  相似文献   
120.
With more and more organizations seeking opportunities to generate benefits beyond compliance from environmental management activities, the challenges for environmental directors today is to develop and implement an environmental strategy that links environmental performance with the overarching strategic business goals of the organization. Organizations today are looking for opportunities to develop environmental management solutions that not only address the concerns of regulatory stakeholders, but also provide opportunities to improve operating efficiency and financial performance, enhance customer satisfaction, sustain market growth, and enhance goodwill, to satisfy the demands of a broader set of stakeholder groups including customers, investors, and employees. To achieve broader benefits from environmental management investments, this article shows how organizations must first develop a methodology for aligning their environmental management activities with the organization's strategic business goals and create a plan for systematically managing continuous improvement to achieve these goals. The second challenge is to implement this strategy at the business unit and facility level in a manner which integrates environmental management activities with an organization's core business processes to achieve improved product and service performance.  相似文献   
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