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991.
This article analyzes and carries out an econometric test of the explanatory power of economic and attitude variables for
occurrences of the nonnative signal crayfish in Swedish waters. Signal crayfish are a carrier of plague which threatens the
native noble crayfish with extinction. Crayfish are associated with recreational and cultural traditions in Sweden, which
may run against environmental preferences for preserving native species. Econometric analysis is carried out using panel data
at the municipality level with economic factors and attitudes as explanatory variables, which are derived from a simple dynamic
harvesting model. A log-normal model is used for the regression analysis, and the results indicate significant impacts on
occurrences of waters with signal crayfish of changes in both economic and attitude variables. Variables reflecting environmental
and recreational preferences have unexpected signs, where the former variable has a positive and the latter a negative impact
on occurrences of waters with signal crayfish. These effects are, however, counteracted by their respective interaction effect
with income. 相似文献
992.
Use of Descriptors of Ecosystem Functioning for Monitoring a National Park Network: A Remote Sensing Approach 总被引:1,自引:0,他引:1
Baseline assessments and monitoring of protected areas are essential for making management decisions, evaluating the effectiveness
of management practices, and tracking the effects of global changes. For these purposes, the analysis of functional attributes
of ecosystems (i.e., different aspects of the exchange of matter and energy) has advantages over the traditional use of structural
attributes, like a quicker response to disturbances and the fact that they are easily monitored through remote sensing. In
this study, we described the spatiotemporal patterns of different aspects of the ecosystem functioning of the Spanish national
parks and their response to environmental changes between 1982 and 2006. To do so, we used the NOAA/AVHRR-GIMMS dataset of
the Normalized Difference Vegetation Index (NDVI), a linear estimator of the fraction of photosynthetic active radiation intercepted
by vegetation, which is the main control of carbon gains. Nearly all parks have significantly changed during the last 25 years:
The radiation interception has increased, the contrast between the growing and nongrowing seasons has diminished, and the
dates of maximum and minimum interception have advanced. Some parks concentrated more changes than others and the degree of
change varied depending on their different environmental conditions, management, and conservation histories. Our approach
identified reference conditions and temporal changes for different aspects of ecosystem functioning, which can be used for
management purposes of protected areas in response to global changes. 相似文献
993.
Sustainability assessment (SA) is a holistic and long-range strategic instrument capable of assisting policy-making in electing,
and deciding upon, future development priorities. The outcomes of an SA process become more relevant and strengthened when
conducted with multi-stakeholder engagement, which provides for multiple dialogues and perspectives. This was the object of
research of the SA team in the context of BioScene (Scenarios for Reconciling Biodiversity Conservation with Declining Agriculture Use in Mountain Areas in Europe), a three-year project (2002–2005) funded by the European Union 5th Framework Program, which aimed to investigate the implications
of agricultural restructuring and decline for biodiversity conservation in the mountain areas of Europe, using three distinct
methodological streams: the ecological, the socio-economic, and the SA approaches. The SA approach drew on the previous two
to assess the importance for biodiversity management of different scenarios of agri-environmental change and rural policy
in six countries (France, Greece, Norway, Slovakia, Switzerland, and the United Kingdom), develop causal chains, include stakeholder
views, and identify potential contributions for, or conflicts with, sustainability. This article tells how SA was used, what
sustainability meant in each study area through different objectives of sustainability considered, discusses the methods used
in SA, and the benefits arising. The SA was conducted by a team independent of any study area, who developed and oversaw the
application of the SA methodology, assisting national teams, and developing a cross-country understanding of the sustainability
of proposed scenarios in the different geographical and social contexts, and their implications for policy-making. Finally,
it reflects on the persistent challenges of interdisciplinary research, compounded by multi-cultural teams, and concludes
on the BioScene’s lessons for the further development and application of SA.
相似文献
William R. SheateEmail: |
994.
Agri-environment programs aim to secure environmental and social stewardship services through payments to farmers. A critical
component of many agri-environment programs is an agri-environment index (AEI) used to quantify benefits and target investments.
An AEI will typically comprise multiple indicators, which are weighted and combined using a utility function, to measure the
benefit of investment options (e.g., projects, farms, regions). This article presents a review of AEIs with 11 case studies
from agri-environment programs in the United States, Australia, and the United Kingdom. We identify a generic procedure used
to define AEIs and explore the implications of alternative methodological approaches. We conclude that AEIs have become an
extremely important policy instrument and make suggestions for their improvement. 相似文献
995.
Yung-Ping Tseng Gerard T. Kyle C. Scott Shafer Alan R. Graefe Timothy A. Bradle Michael A. Schuett 《Environmental management》2009,43(3):496-507
Along with the growing boating population and the number of boats in use on limited inland waterways, boater expectations
of setting density, safety perceptions, and the associated impacts on their experience (e.g., satisfaction) are becoming increasingly
important. The primary purpose of this article was to explore a recreational boating crowding–satisfaction model derived from
previous work using safety and enjoyment as mediating variables. We also tested our crowding–satisfaction model among day
and overnight users. Our analysis revealed no significant difference between day and overnight users for any of the relationships
tested in our model. Our final model indicated as respondents’ expectations for seeing people increased along with their feelings
of being crowded, they were more inclined to consider the conditions on the lake as being unsafe. They were also more inclined
to indicate that the number of people they had seen on the lake detracted from their boating experience. Respondents’ satisfaction
was tied to their perceptions of crowding. Mediating variables illustrated that the relationship was conditioned by perceptions
of safety and enjoyment. Analysis of the indirect effect observed in our study illustrate that when the number of people seen
on the lake exceed respondents’ expectations, their perceptions of safety and enjoyment both decline, resulting in lower satisfaction.
These findings have implications for managing recreational boating use on inland lake systems. Given the role played by expectations
in our model, efforts to communicate with boaters about conditions on these waterways is important for helping them plan their
boating experience and avoid situations they consider unsafe or unsatisfactory. 相似文献
996.
Itziar de Aranzabal María F. Schmitz Francisco D. Pineda 《Environmental management》2009,44(5):938-951
Tourism and landscape are interdependent concepts. Nature- and culture-based tourism are now quite well developed activities
and can constitute an excellent way of exploiting the natural resources of certain areas, and should therefore be considered
as key objectives in landscape planning and management in a growing number of countries. All of this calls for careful evaluation
of the effects of tourism on the territory. This article focuses on an integrated spatial method for landscape analysis aimed
at quantifying the relationship between preferences of visitors and landscape features. The spatial expression of the model
relating types of leisure and recreational preferences to the potential capacity of the landscape to meet them involves a
set of maps showing degrees of potential visitor satisfaction. The method constitutes a useful tool for the design of tourism
planning and management strategies, with landscape conservation as a reference. 相似文献
997.
Papadopoulos F Parissopoulos G Papadopoulos A Zdragas A Ntanos D Prochaska C Metaxa I 《Environmental management》2009,43(1):135-143
Field research was carried out to assess the effects of the application of reclaimed municipal wastewater on rice cultivation
in Thessaloniki, Greece during a 2-year period (1999–2000). Effects on production cost, soil composition, and health risk
were examined. A randomized complete block design was used for the paddy field with three treatments and four replicates.
The treatments were (1) river irrigation water with N–P fertilization, (2) reclaimed wastewater irrigation with surface N
fertilization, and (3) reclaimed wastewater irrigation without fertilization. The results showed that the total production
cost decreased 8.8% and 11.9% by applying the second and third treatments, respectively, compared to the first treatment,
without significant differences in the agronomic and rice quality traits. Soil composition showed discrepancies between the
2 years and the three treatments, whereas the pathogens of the reclaimed wastewater and rice tissues posed a low human risk
when taking the needed precautions. 相似文献
998.
This paper presents an innovative, quantitative assessment of pollution avoidance attributable to environmental regulation enforced through integrated licensing, using Ireland's pharmaceutical-manufacturing sector as a case study. Emissions data reported by pharmaceutical installations were aggregated into a pollution trend using an Environmental Emissions Index (EEI) based on Lifecycle Assessment methodologies. Complete sectoral emissions data from 2001 to 2007 were extrapolated back to 1995, based on available data. Production volume data were used to derive a sectoral production index, and determine ‘no-improvement’ emission trends, whilst questionnaire responses from 20 industry representatives were used to quantify the contribution of integrated licensing to emission avoidance relative to these trends. Between 2001 and 2007, there was a 40% absolute reduction in direct pollution from 27 core installations, and 45% pollution avoidance relative to hypothetical ‘no-improvement’ pollution. It was estimated that environmental regulation avoided 20% of ‘no-improvement’ pollution, in addition to 25% avoidance under business-as-usual. For specific emissions, avoidance ranged from 14% and 30 kt a− 1 for CO2 to 88% and 598 t a− 1 for SOx. Between 1995 and 2007, there was a 59% absolute reduction in direct pollution, and 76% pollution avoidance. Pollution avoidance was dominated by reductions in emissions of VOCs, SOx and NOx to air, and emissions of heavy metals to water. Pollution avoidance of 35% was attributed to integrated licensing, ranging from between 8% and 2.9 t a− 1 for phosphorus emissions to water to 49% and 3143 t a− 1 for SOx emissions to air. Environmental regulation enforced through integrated licensing has been the major driver of substantial pollution avoidance achieved by Ireland's pharmaceutical sector — through emission limit values associated with Best Available Techniques, emissions monitoring and reporting requirements, and performance targets specified in environmental management plans. This compliant sector offers a positive, but not necessarily typical, case study of IPPC effectiveness. 相似文献
999.
Aourell Mauffret André Rottiers Thomas Federle David C. Gillan Miriam Hampel Julian Blasco Ali Temara 《Environment international》2009,35(6):885-892
An innovative biodegradation test system was developed in order to fill the current gap for cost effective and environmentally relevant tools to assess marine biodegradability. Glass beads were colonized by a biofilm in an open flow-through system of seawater with continuous pre-exposure to Linear Alkylbenzene Sulfonate (LAS) (20 μg/L). Thereafter, such colonized beads were added as inoculum in different test systems. [14C]-LAS (5–100 μg/L) was added and primary and ultimate biodegradation were assessed. The bacterial density collected on the beads (109 bact./mL beads) was ca. 3 orders of magnitude higher than the typical seawater content. The LAS mineralization lag phase duration decreased from 55 to < 1 days and the mineralization extent increased from 53 to 90% as the colonized beads volume increased from 10 to 275 mL. This is the first demonstration of marine bacteria's ability to mineralize LAS. On the opposite, less than 13% LAS was mineralized in seawater only. The colonized beads possibly enhanced the probability to encounter the full degraders' consortium in a low volume of seawater (100 mL). 相似文献
1000.
Protection of the environment from ionising radiation in a regulatory context (protect): proposed numerical benchmark values 总被引:1,自引:1,他引:0