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751.
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
752.
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
753.
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: |
754.
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
755.
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
756.
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
757.
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
758.
Kangjoo Kim Sung-Min Park Jinsam Kim Seok-Hwi Kim Yeongkyoo Kim Jeong-Tae Moon Gab-Soo Hwang Wang-Seog Cha 《Chemosphere》2009,77(2):222-227
The geochemical behavior of As in porewaters of an alkaline coal ash disposal site was investigated using multilevel samplers. The disposal site was in operation from 1983 until 1994 and was covered with 0.3–0.5 m thick soils in 2001 when this study was initiated. Sequential extraction analyses and batch leaching experiments were also performed using the coal ash samples collected from the disposal site. The results suggest the important roles of siderite (FeCO3) precipitation/dissolution and soil cover, which have been ignored previously. Arsenic levels in the porewater were very low (average of 10 μg L−1) when the site was covered with soil due to coprecipitation with siderite. The soil cover enabled the creation of anoxic conditions, which raised the Fe concentration by the reductive dissolution of Fe-(hydr)oxides. Because of the high alkalinity generated from the alkaline coal ash, even a small increase in the Fe concentration (0.66 mg L−1 on average) could cause siderite precipitation. When the soil cover was removed, however, an oxidizing condition was created and triggered the precipitation of dissolved Fe as (hydr)oxides. As a result, the dissolution of previously precipitated As-rich siderite caused higher As concentration in the porewater (average of 345 μg L−1). 相似文献
759.
A study was conducted to investigate the effects of time-gap settings and contents of secondary tasks on a fix-based bus driving simulator on drivers’ performance while reclaiming control from ACC in a car-following scenario of emergency brake by the lead vehicle. Thirty professional bus drivers drove on the simulator with the scenario of highway traffic flow under 12 random time-gap settings: from 0.64 s to 2.40 s with the interval of 0.16 s. As for the effects of secondary tasks, subjects were evenly divided into three conditions: no secondary task interference, simple secondary task, and complex task. The results demonstrated that different safety demarcations of time-gaps on subjective acceptance and driving performance can be found out. The integrated demarcations separated time-gaps into divisions that represented different levels of danger. It revealed that the safer time-gaps for different situations were: longer than 1.60 s for none-secondary task distraction and longer than 2.08 s for being continuously distracted by secondary tasks. The demand for simple tasks is relatively high, so a larger time-gap is needed for the driver to remain safe. This research has implications for the time-gap selection of ACC and effects of secondary task distraction on buses. A next logical step will focus on determining time-gaps for lead vehicles on curves or slopes, when multiple vehicles are present ahead, and modeling driver behavior and performance with ACC for cars, buses, and other types of vehicles. 相似文献
760.
This study proposes and employs a structural model to examine the effects of environmental literacy, environmental awareness, environmental attitudes, and environmental behavior among middle school students in Eski?ehir on their purchase of environmentally friendly products. In the proposed structural model, environmental illiteracy and environmental awareness were the exogenous latent variables, while pro-environmental attitude, pro-environmental behavior, and the purchase of environmentally friendly products were the endogenous latent variables. The latent variable of environmental illiteracy did not have a statistically significant effect on environmental attitudes and purchase of environmentally friendly products, whereas environmental awareness had a positive effect on pro-environmental attitudes and the purchase of environmentally friendly products. These findings indicate that students with environmental awareness also develop positive attitudes toward the environment, and the presence of a positive attitude toward the environment leads them to display pro-environmental behaviors and adopt a positive attitude toward environmentally friendly products. 相似文献