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251.
Multiple forms of valuation contribute to public acceptance of conservation projects. Here, we consider how esthetic, intrinsic, and utilitarian values contribute to public attitudes toward a proposed reintroduction of guanaco (Lama guanicoe) in a silvopastoral system of central Chile. The nexus among landscape perceptions and valuations, support for reintroductions, and management of anthropogenic habitats is of increasing interest due to the proliferation of conservation approaches combining some or all of these elements, including rewilding and reconciliation ecology, for example. We assessed attitudes and values through an online questionnaire for residents of Santiago, Chile, using multiple methods including photo-montages and Likert scale assessments of value-based statements. We also combined the questionnaire approach with key informant interviews. We find strong support for the reintroduction of guanacos into the Chilean silvopastoral system (‘espinal’) in terms of esthetic and intrinsic values but less in terms of utilitarian values. Respondents preferred a scenario of espinal with guanacos and expressed interest in visiting it, as well as support for the reintroduction project on the basis that guanacos are native to central Chile. We suggest that reintroduced guanacos could serve as a ‘phoenix flagship species’ for espinal conservation, that is, a flagship species that has gone regionally extinct and is known but not associated with the region in the cultural memory. We consider how the lack of local cultural identity can both help and weaken phoenix flagships, which we expect to become more common. 相似文献
252.
Nathalie Colbach 《Environmental science and pollution research international》2009,16(3):348-360
253.
The digital workshop: exploring the use of interactive and immersive visualisation tools in participatory planning 总被引:1,自引:0,他引:1
Salter JD Campbell C Journeay M Sheppard SR 《Journal of environmental management》2009,90(6):2090-2101
This paper examines the emerging role of digital tools in a collaborative planning process for British Columbia's Bowen Island. The goal of this research was to evaluate the effectiveness of a 'digital workshop', combining the interactive CommunityViz tool with the immersive lab facilities at the Collaborative for Advanced Landscape Planning (CALP). In support of the larger community planning process, two 3-h workshops were held at CALP's Landscape Immersion Lab. To facilitate collaborative exploration, the interactive landscape visualisation and real-time data analysis capabilities of CommunityViz were employed to illustrate the possible outcomes of residential density policies for Bowen Island's Snug Cove community. The community planning workshops were structured to provide the 14 semi-expert participants with the opportunity to explore and discuss the contentious residential density components of the draft Snug Cove Village Plan. The abilities to dynamically explore the visualisations of the planning proposals, and to see real-time changes in indicator metrics were considered particularly informative, and appeared to increase participants' understanding of the plan. Written and verbal responses indicated, however, that there was insufficient time to examine and interact with the information during the workshop, suggesting a need to examine in greater depth how and when these tools might best be employed in collaborative settings. Current and future research relating to this project is discussed. 相似文献
254.
Sand-trapping fences modify the character of the coastal landscape and change its spatial structure, image, and meaning. This
paper examines the relationship between these changes and fence usage at the municipal level, where most decisions about fence
deployment are made. Use of fences in 29 municipalities on the developed coast of New Jersey is examined over a 6-year period.
Interviews with municipal officers indicate that wooden slat sand-trapping fences are used primarily to build dunes to provide
protection against wave uprush and flooding, but they are also used to control pedestrian traffic and demarcate territory.
These uses result in changes in landforms and habitats. An aerial video inventory of fences taken in 2002 indicates that 82%
of the shoreline had fences and 72% had dunes. Single and double straight fence rows are the most commonly used. Fences are
often built to accomplish a specific primary purpose, but they can cause many different and often unanticipated changes to
the landscape. The effects of a sand fence change through time as the initial structure traps sand, creates a dune that is
colonized by vegetation, and becomes integrated into the environment by increasing topographic variability and aesthetic and
habitat value. Sand fences can be made more compatible with natural processes by not placing them in locations where sources
of wind blown sand are restricted or in unnatural shore perpendicular orientations. Symbolic fences are less expensive, are
easy to replace when damaged, are less visually intrusive, and can be used for controlling pedestrian access. 相似文献
255.
Ecologists are beginning to recognize the effect of heterogeneity on structure and function in arid and semiarid ecosystems.
Additionally, the influences of temperature on ecosystems are widely documented, but landscape temperature patterns and relationships
with vegetation are rarely reported in ecological studies. To better understand the importance of temperature patterns to
the conservation and restoration of native ecosystems, we designed an experiment to investigate relationships among soil surface
temperature, landscape heterogeneity, and grazing intensity. Grazing intensity did influence the vegetation structure and
composition. Heavy treatments had the greatest bare ground and the least vertical structure. Ungrazed treatments had the most
litter and live grass cover. However, average temperatures among the three grazing treatments were not different and ranged
less than 2°C during midday summer periods. The temperature difference between riparian and upland landscapes within grazing
treatments was 21°C. Landscape position (riparian vs. upland) did have a significant influence on soil surface temperature
and produced a variation in temperature 11 times greater than grazing intensities. Thermal heterogeneity did not differ among
grazing treatments. Lower soil surface temperatures (associated with riparian areas) may provide a critical thermal refuge
for many animals in arid and semiarid ecosystems on hot summer days, when air temperatures can exceed 37°C. Riparian zones,
specifically riparian vegetation, are an important component in ecosystem management. 相似文献
256.
Mehrey G. Vaghti Marcel Holyoak Amy Williams Theresa S. Talley Alexander K. Fremier Steven E. Greco 《Environmental management》2009,43(1):28-37
Societal constraints often limit full process restoration in large river systems, making local rehabilitation activities valuable
for regeneration of riparian vegetation. A target of much mitigation and restoration is the federally threatened Valley elderberry
longhorn beetle and its sole host plant, blue elderberry, in upper riparian floodplain environments. However, blue elderberry
ecology is not well understood and restoration attempts typically have low success rates. We determined broad-scale habitat
characteristics of elderberry in altered systems and examined associated plant species composition in remnant habitat. We
quantified vegetation community composition in 139 remnant riparian forest patches along the Sacramento River and elderberry
stem diameters along this and four adjacent rivers. The greatest proportion of plots containing elderberry was located on
higher and older floodplain surfaces and in riparian woodlands dominated by black walnut. Blue elderberry saplings and shrubs
with stems <5.0 cm in diameter were rare, suggesting a lack of recruitment. A complex suite of vegetation was associated with
blue elderberry, including several invasive species which are potentially outcompeting seedlings for light, water, or other
resources. Such lack of recruitment places increased importance on horticultural restoration for the survival of an imperiled
species. These findings further indicate a need to ascertain whether intervention is necessary to maintain functional and
diverse riparian woodlands, and a need to monitor vegetative species composition over time, especially in relation to flow
regulation. 相似文献
257.
Conservation and protection of soil and water resources and visual aspects of landscape, as well as the promotion of biodiversity, are some of the central tasks of environmental policy development and social politics in the future. One of the main questions is: ‘which agricultural systems are able to guarantee sustained resource-conserving land use?’ Based on the ecological risk concepts of the 1970s and 1980s, a potential impact model was developed using a universal assessment algorithm derived from fuzzy logic. The model estimated the potential impact of agricultural land use on ecosystem function using a few resource indicators. Intervention intensities of agricultural land-use are set in relation to site conditions and aggregated for each of several defined potential impact categories. The interpretation with respect to risk and the calculation of potential impact values are explained. 相似文献
258.
Assessment of the contribution of land use pattern and intensity to landscape quality: use of a landscape indicator 总被引:4,自引:0,他引:4
The objective of this research work is the evaluation of the impact of landuse pattern and intensity on landscape by means of an indicator. The method used to calculate a ‘landscape indicator’ (Iland) allows to take into account the objective as well as the subjective approach of landscape. Iland corresponds to the degree of agreement between landscape supply by farmers and landscape demand by the social groups. The supply and the demand are evaluated through four criteria: ‘diversity’, ‘upkeep’, ‘openness’ and ‘heritage’. The landscape supply is calculated from data of landscape objects (punctual, linear and spatial) for each criterion recorded at the field level. The values of the four criteria for the landscape demand are allocated by the user(s) of the indicator (decision makers, regional council, social groups…) into five classes (0–4). The value of the landscape indicator is the least favourable difference between supply and demand for the four criteria. An example of calculation of the ‘landscape indicator’ for an arable farm is given. The collection of data needs 2 h with the farmer and 2 h for a survey of the farm land. 相似文献
259.
Start-up performances of dry anaerobic mesophilic and thermophilic digestions of organic solid wastes 总被引:6,自引:0,他引:6
Two dry anaerobic digestions of organic solid wastes were conducted for 6 weeks in a lab-scale batch experiment for investigating the start-up performances under mesophilic and thermophilic conditions. The enzymatic activities, i.e., β-glucosidase, N-α-benzoyl-Largininamide (BAA)-hydrolysing protease, urease and phosphatase activities were analysed. The BAA-hydrolysing protease activity during the first 2-3 weeks was low with low pH, but was enhanced later with the pH increase. β-Glucosidase activity showed the lowest values in weeks 1-2, and recovered with the increase of BAA-hydrolysing protease activity. Acetic acid dominated most of the total VFAs in thermophilic digestion, while propionate and butyrate dominated in mesophilic digestion. Thermophilic digestion was confirmed more feasible for achieving better performance against misbalance, especially during the start-up period in a dry anaerobic digestion process. 相似文献
260.
Characterization and distribution of polycyclic aromatic hydrocarbon in sediments of Haihe River, Tianjin, China 总被引:7,自引:0,他引:7
JIANG Bin ZHENG Hai-long HUANG Guo-qiang DING Hui LI Xin-gang SUO Hong-tu LI Rui 《环境科学学报(英文版)》2007,19(3):306-311
In this study sediment samples were collected from 13 sites of Haihe River in Tianjin City, China, sixteen of priority polycyclic aromatic hydrocarbons (PAHs) listed in USEPA were analyzed by means of GC-MS. The total concentrations of PAH ranged from 774.81 to 255371.91 ng/g dw, and two to four rings of PAHs were dominant in sediment samples. Molecular ratios, such as phenanthrene/anthracene, fluoranthene/pyrene and low-molecular-weight PAH/high-molecular-weight PAH, were used to study the possible sources of pollution. It indicated a mixed pattern of parolytic and petrogenic inputs of PAHs in sediments in Haihe River. The petrogenic PAHs may be mainly derived from the leakage of refined products, e.g., gasoline, diesel fuel and fuel oil vehicle traffics or gas stations from urban area. The pyrolytic PAHs might be from the discharge of industrial wastewater and the emission of atmospheric particles from petrochemical factories. In addition, the levels of PAHs in the urban and industrial areas are far beyond the values reported from other rivers and marine systems reported. This situation may be due to polluted discharging from some petrochemical industrial manufactories and worse traffic conditions in Tianjin. 相似文献