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101.
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One goal of this paper is to present a perspective on psychological research in which the relationship between person and environment is the central point of interest. The german term Oekopsychologie is introduced as a higher level framework that subsumes both, the theory-oriented ecological perspective (the Oekologische Psychologie in German), and problem-oriented and environmental psychology (the Umweltpsychologie in German) with its more applied character. It is argued that the ecological perspective should be based on 10 tenets which stem from an emphasis on the fundamental importance of the man-environment relationship. The paper is also an attempt to stimulate bridge-building activities between German-speaking and English-speaking environmental psychologists.  相似文献   
103.
Forty‐five flood control reservoirs, authorized in the Watershed Protection and Flood Prevention Act 1954, were installed by United States Department of Agriculture (USDA) between 1969 and 1982 in the Little Washita River Experimental Watershed (LWREW), located in central Oklahoma. Over time, these reservoirs have lost sediment and flood storage capacity due to sedimentation, with rates dependent on upstream land use and climate variability. In this study, sedimentation rates for 12 reservoirs representing three major land use categories within LWREW were measured based on bathymetric surveys that used acoustic profiling system. Physiographic and climate attributes of drainage area of surveyed reservoirs were extracted from publicly available data sources including topographic maps, digital elevation models, USDA Natural Resource Conservation Service soils, and weather station databases. Correlation, principal component analysis, and stepwise regression were utilized to analyze the relationship between normalized reservoir sedimentation rates (ReSRa) and the drainage area characteristics to determine the major variables controlling sedimentation within the LWREW. Percent of drainage area with extreme slopes, saturated hydraulic conductivity, and maximum daily rainfall event recorded in spring explained most of the variability in ReSRa. It was also found that percent reduction in reservoir surface area can be used as a surrogate for estimating ReSRa. The implications of the results are discussed.  相似文献   
104.
The presence of prey heterogeneity and weakly interacting prey species is frequently viewed as a stabilizer of predator-prey dynamics, countering the destabilizing effects of enrichment and reducing the amplitude of population cycles. However, prior model explorations have largely focused on long-term, dynamic attractors rather than transient dynamics. Recent theoretical work shows that the presence of prey that are defended from predation can have strongly divergent effects on dynamics depending on time scale: prey heterogeneity can counteract the destabilizing effects of enrichment on predator-prey dynamics at long time scales but strongly destabilize systems during transient phases by creating long periods of low predator/prey abundance and increasing extinction probability (an effect that is amplified with increasing enrichment). We tested these general predictions using a planktonic system composed of a zooplankton predator and multiple algal prey. We first parameterized a model of our system to generate predictions and tested these experimentally. Our results qualitatively supported several model predictions. During transient phases, presence of defended algal prey increased predator extinctions at low and high enrichment levels compared to systems with only a single edible prey. This destabilizing effect was moderated at higher dilution rates, as predicted by our model. When examining dynamics beyond initial oscillations, presence of the defended prey increased predator-prey temporal variability at high nutrient enrichment but had no effect at low nutrient levels. Our results highlight the importance of considering transient dynamics when assessing the role of stabilizing factors on the dynamics of food webs.  相似文献   
105.
We investigated the effect of leaf age on the response of net photosynthesis (A), stomatal conductance (gwv), foliar injury, and leaf nitrogen concentration (NL) to tropospheric ozone (O3) on Prunus serotina seedlings grown in open-plots (AA) and open-top chambers, supplied with either carbon-filtered or non-filtered air. We found significant variation in A, gwv, foliar injury, and NL (P < 0.05) among O3 treatments. Seedlings in AA showed the highest A and gwv due to relatively low vapor pressure deficit (VPD). Older leaves showed significantly lower A, gwv, NL, and higher foliar injury (P < 0.001) than younger leaves. Leaf age affected the response of A, gwv, and foliar injury to O3. Both VPD and NL had a strong influence on leaf gas exchange. Foliar O3-induced injury appeared when cumulative O3 uptake reached 8-12 mmol m−2, depending on soil water availability. The mechanistic assessment of O3-induced injury is a valuable approach for a biologically relevant O3 risk assessment for forest trees.  相似文献   
106.
By 2012, Hammarby Sjöstad, a former large industrial harbor area in southern Stockholm, Sweden, will be a fully developed residential district containing approximately 11,000 apartments and accommodating 35,000 people. The transformation of the area began in 1996, and the development soon became renowned for its ambitious environmental program, inspired by Agenda 21 (United Nations in Rio declaration on environment and development. United Nations Department of Economic and Social Affairs (DESA), Rio de Janeiro, 1992) and the Sydney 2000 Olympics in Australia (Newman in Landsc Urban Plan 44:219–226, 1999). Using results based on literature reviews, in-depth interviews, discussions with focus groups, and quantitative data, this paper attempts to gain insight into how the environmental program influenced the planning and performance of the district with regard to sustainable urban development. In doing so, three important conclusions were maintained that could be valuable for similar projects concerning the planning and development of sustainable urban districts. First, the environmental program proved vital to the development process of Hammarby Sjöstad, specifically in its drive to create a sustainable urban district. When planning on improving the sustainability of future districts, such a program should be introduced and integrated earlier in the planning stage of the district. Second, the metabolic flows of Hammarby Sjöstad were reduced as a result of the integrated system—the Hammarby Model—of Hammarby Sjöstad. In order to reduce the metabolic flows in future urban districts even further, it is important to facilitate the integration of technical innovations into existing integrated systems. Third, this case study showed that there was a loss of valid and credible data related to the aims and goals of the environmental program of Hammarby Sjöstad. In future urban districts, it is of the utmost importance to include a clear structure of the assessment process in the environmental program, which would ensure the quality of gathered data and facilitate the development of even better sustainable urban districts in the future.  相似文献   
107.
The focus of this article was to explore the translocation of 109Cd, 57Co, 65Zn, 63Ni, and 134Cs via xylem and phloem in the newly found hyperaccumulator Solanum nigrum L. Two experiments with the uptake via the roots and transport of 109Cd, 57Co, and 65Zn labeled by roots, and the redistribution of 109Cd, 65Zn, 57Co, 63Ni, and 134Cs using flap label in S. nigrum in a hydroponic culture with a standard nutrient solution were conducted. The results showed that 109Cd added for 24 h to the nutrient medium of young plants was rapidly taken up, transferred to the shoot, and accumulated in the cotyledons and the oldest leaves but was not efficiently redistributed within the shoot afterward leading to a rather low content in the fruits. In contrast, 57Co was more slowly taken up and released to the shoot, but afterward, this element was redistributed from older leaves to younger leaves and maturing fruits. 65Zn was rapidly taken up and transferred to the shoot (mainly to the youngest leaves and not to the cotyledons). Afterward, this radionuclide was redistributed within the shoot to the youngest organs and finally accumulated in the maturing fruits. After flap labeling, all five heavy metals tested (109Cd, 57Co, 65Zn, 63Ni, 134Cs) were exported from the labeled leaf and redistributed within the plant. The accumulation in the fruits was most pronounced for 63Ni and 65Zn, while a relatively high percentage of 57Co was finally found in the roots. 134Cs was roughly in the middle of them. The transport of 109Cd differed from that previously reported for wheat or lupin and might be important for the potential of S. nigrum to hyperaccumulate cadmium.  相似文献   
108.
This article is the third in a series prepared to explain the Teller County growth management planning process. Once it was determined by local decision-makers that Teller County, Colorado, would pursue a policy of directed growth, concepts based on this policy were developed. These concepts presented visions and options for the future. Landscape plans then were developed for Teller County and the City of Woodland Park planning area so that these options could be visualized by local leaders and the public. The landscape plans were used as part of the ongoing citizen involvement process to inform the public about the options for growth management. To provide even more information, detailed designs were developed for specific areas in the county. From the landscape plan, public involvement effort, and detailed designs, specific implementation measures were identified, discussed, and adopted. These measures included guidelines for administration, so that county and city goals could be linked to the actual day-to-day management of development proposals. Paper 3 in a series of 3.  相似文献   
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