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601.
Management and valuation of an environmentally sensitive area: Norfolk Broadland,England, case study 总被引:1,自引:0,他引:1
Wetlands, like any other environmentally sensitive resource, require very careful evaluation. While it is accepted that all wetlands may be equally valuable in terms of maintaining global life-support systems, individual areas may be ranked according to their uniqueness or the irreplaceability of the resource should the wetland be developed. The various techniques available for evaluating the wetland resource in the development versus conservation conflict situation are critically assessed. Indirect appraisal via the opportunity cost method can generate valuable data which have contributed to the mitigation of such conflict situations.The Broadland, in Norfolk, England, recently designated an environmentally sensitive area (ESA), provides a case study example of wetland management. The search for an acceptable flood alleviation strategy for the ESA is examined in detail. The economic and environmental asset structure of the study area is examined at two levels. A basic screening system is applied to each of the identified flood protection planning units to enable the rank ordering of the units. A more detailed appraisal is then made of the value of selected units so that the cost-effectiveness of any planned expenditure on flood protection works can be assessed. Specific management issues and their likely effect on the environment, in terms of land use for example, are also addressed. The 1986 Agriculture Act marks a potential watershed in British conservation policy. The ESA policy encompasses a dual management strategy that attempts to stimulate compatible agricultural and conservation practices and activities. Other countries that still retain significant unspoiled wetland resources may find that preemptive regulatory government intervention in favor of conservation would help to avoid the worst aspects of the British experience. 相似文献
602.
David J. Parsons David M. Graber James K. Agee Jan W. Van Wagtendonk 《Environmental management》1986,10(1):21-24
An evolving understanding of ecological processes, together with ambiguities in National Park Service policy, have led to multiple interpretations of the role of management in our large natural area National Parks. National Park Service management policies must be dynamic and responsive to changes in scientific knowledge and societal values. We propose that the principal aim of NPS resource management in natural areas is the unimpeded interaction of native ecosystem processes and structural elements. The case of the changing role of natural fire management is used as an example in developing this rationale. 相似文献
603.
Veronica M. Sol Petronella E. M. Lammers Harry Aiking Joop de Boer Jan F. Feenstra 《Environmental management》1995,19(3):457-467
This paper describes the development of an integrated environmental index that may serve as a representation of the general
environmental quality at a certain location. This index is meant to be used by local administrators to strike a balance between
the development of industrial activities and the protection of sensitive land-uses (housing). The approach used to arrive
at this index, based on health considerations, is described, detailing the different steps in the construction of the index:
identification, assessment, summation, valuation and aggregation. The index combines environmental quality information concerning
noise, odor, air pollution, and risk of industrial calamities. The resulting integrated environmental index is illustrated
using data of a pilot project. 相似文献
604.
Vladimir Kucera Johan Tidblad Katerina Kreislova Dagmar Knotkova Markus Faller Daniel Reiss Rolf Snethlage Tim Yates Jan Henriksen Manfred Schreiner Michael Melcher Martin Ferm Roger-Alexandre Lefèvre Joanna Kobus 《Water, Air, & Soil Pollution: Focus》2007,7(1-3):249-258
A “multi-pollutant exposure programme” reflecting the new pollution situation where SO2 is no longer the dominating pollutant has been performed by the International Co-operative Programme on Effects on Materials,
including Historic and Cultural Monuments (ICP Materials) within the activities of the Convention on Long-range Transboundary
Air Pollution. The main results obtained in the period 1997–2003 are summarised. Dose-response functions are presented for
carbon steel, zinc, copper, bronze and limestone. Parameters involved in the functions include besides SO2 and pH, which were included in the previously developed functions from ICP Materials, also the effect of particulate matter
and HNO3. 相似文献
605.
Within the European monitoring network (EMEP, ) several different sampling procedures for measuring the main air components have been applied. This has contributed to systematic
concentration differences and a comparability problem. Since 1997 co-located experiments in 15 countries have been carried
out to quantify these differences. In addition, three major measurement campaigns were organized by EMEP between 1985 and
1991. Differences among results depend on the concentration level and methods used. The decrease in SO2 concentrations over the last twenty years has placed greater demands on the methodology. Absorbing solutions methods for
SO2, (H2O2 and tetrachloromercurate (TCM)) typically have higher detection limits than the reference method, which uses KOH impregnated
filters. The TCM method also has problems with negative interference, especially in summertime. UV fluorescence monitors have
in a few cases proven to give good results, but interferences, detection limit and poor maintenance can be problems. For NO2, many countries are using the TGS absorption solution method, which has a higher detection limit than the reference method
using NaI impregnated glass sinters. The Salzmann method gives unreliable results at concentrations below 1 μgN/m3, and even at higher concentrations the uncertainty is rather unsatisfactory. The chemiluminescence monitor with molybdenum
converters tends to systematically overestimate NO2 concentrations, possibly because zero-drift problems and the non-specific response to NO2. Particulate sulphate measurements in general have lower bias and uncertainties than gas and other aerosol measurements. 相似文献
606.
Marianne Lindström Maria Johansson Jan Herrmann Olle Johnsson 《Journal of Environmental Planning and Management》2006,49(4):495-513
Human actions towards land, freshwater and oceans have already caused biodiversity to decline. This study aims to investigate attitudes towards the conservation of biological biodiversity among different groups in a Swedish city, Kristianstad. An inquiry including statements measuring attitudes towards the conservation of habitats, animals and plants, to the biological diversity within selected local areas, to global and national areas, and to societal issues, was replied to by 271 persons. Deciduous forests, birds and wild flowers were given highest priority. An area categorized as wetland including lakeshore meadows with a rich bird life was prioritized as most important for conservation while a forest area was chosen as best for recreation. The experts gave lower priority to arable land, urban parks, domestic animals, agricultural and garden plants and to conifer forests compared to the other groups. Knowledge about what people in general value as important could facilitate the future planning of nature areas in the city of Kristianstad. 相似文献
607.
Hongjie Xie Xiaobing Zhou Jan M.H. Hendrickx Enrique R. Vivoni Huade Guan Yong Q. Tian Eric E. Small 《Journal of the American Water Resources Association》2006,42(1):237-256
This study examines NEXRAD Stage III product (hourly, cell size 4 km by 4 km) for its ability in estimating precipitation in central New Mexico, a semiarid area. A comparison between Stage III and a network of gauge precipitation estimates during 1995 to 2001 indicates that Stage III (1) overestimates the hourly conditional mean (CM) precipitation by 33 percent in the monsoon season and 55 percent in the nonmonsoon season; (2) overestimates the hourly CM precipitation for concurrent radar‐gauge pairs (nonzero value) by 13 percent in the monsoon season and 6 percent in the nonmonsoon season; (3) overestimates the seasonal precipitation accumulation by 11 to 88 percent in monsoon season and underestimates by 18 to 89 percent in the nonmonsoon season; and (4) either overestimates annual precipitation accumulation up to 28.2 percent or underestimates it up to 11.9 percent. A truncation of 57 to 72 percent of the total rainfall hours is observed in the Stage III data in the nonmonsoon season, which may be the main cause for both the underestimation of the radar rainfall accumulation and the lower conditional probability of radar rainfall detection in the nonmonsoon season. The study results indicate that the truncation caused loss of small rainfall amounts (events) is not effectively corrected by the real‐time rain gauge calibration that can adjust the rainfall rates but cannot recover the truncated small rainfall events. However, the truncation error in the monsoon season may be suppressed due to the larger rainfall rate and/or combined effect of overestimates by bright band and hail contaminations, virga, advection, etc. In general, improvement in NEXRAD performance since the monsoon season in 1998 is observed, which is consistent with the systematic improvement in the NEXRAD network. 相似文献
608.
Andersson P Byegård J Tullborg EL Doe T Hermanson J Winberg A 《Journal of contaminant hydrology》2004,70(3-4):271-297
Experiments were conducted at the Asp? Hard Rock Laboratory in order to improve the understanding of radionuclide retention properties of fractured crystalline bedrock in the 10-100 m scale (TRUE Block Scale Project, jointly funded by ANDRA, ENRESA, Nirex, JNC, Posiva and SKB). A series of tracer experiments were performed using sorbing tracers in three different flow paths. The different flow paths had Euclidian lengths of 14, 17 and 33 m, respectively, and one to three water conducting structures. Four tests were performed using different cocktails made up of radioactive sorbing tracers (22,24Na+, 42K+, 47Ca2+, 85Sr2+, 83,86Rb+, 131,133Ba2+ and 134,137Cs+). For each tracer injection, the breakthrough of sorbing tracers was compared to the breakthrough of a conservative tracer, 82Br-, 131I-, HTO and 186ReO4-, respectively. In the two longer flow paths, no breakthrough of 83Rb+ and 137Cs+ was observed after 8 months of pumping. Selected tracer tests were subject to basic modelling in which a one-dimensional (1D) advection-dispersion model, including surface sorption, and an unlimited matrix diffusion were used for the interpretation of the results. The results of the modelling indicated that there is a slightly higher mass transfer into a highly porous material in the block-scale experiment compared with in situ experiments performed over shorter distances and significantly higher than what would have been expected from laboratory data obtained from studies of the interactions in nonaltered intact rock. 相似文献
609.
Richard Haynes Frans W. A. Brom Jan Elliott Peter Schaber 《Journal of Agricultural and Environmental Ethics》2000,13(1):1-5
Editorial Introduction
From the Editors 相似文献610.
Jan M. Pestka Florian Barvencik Frank T. Beil Robert P. Marshall Eilin Jopp Arndt F. Schilling Andreas Bauerochse Mamoun Fansa Klaus Püschel Michael Amling 《Die Naturwissenschaften》2010,97(4):393-402
Although numerous bodies were deposited in Western European bogs in the past centuries, few were found and underwent archeological
analysis. No studies comparing skeletal structure and mineralization of bog bodies from different ages have been performed
to this day. Therefore, the aim of this study was to analyze and compare skeletal features and specifics of the human remains
of three bog bodies from the Iron and Middle Ages found in Northern European peat bogs. Demineralization due to the acidic
environment in peat bogs was comparably pronounced in all three bodies. Still, the macroscopic state of skeletal preservation
was excellent. In addition to contact radiography, we used peripheral quantitative computed tomography to measure cortical
bone mineral density. The conservation of skeletal three-dimensional microstructural elements was assessed by high-resolution
microcomputed tomography analysis. These techniques revealed severe differences in bone mineral density and enabled us to
determine handedness in all three bodies. Additionally, unique skeletal features like intravital bone lesions, immobilization
osteoporosis, and Harris lines were found. A deformity of the left femoral head was observed which had the typical appearance
of an advanced stage of Legg–Calve–Perthes disease. This study gives detailed insight into the skeletal microstructure and
microarchitecture of 800- to 2,700-year-old bog bodies. Skeletal analysis enables us to draw conclusions not only concerning
changes in the acidic environment of the bog, but also serves as a diagnostic tool to unravel life circumstances and diseases
suffered by humans in the Iron and Middle Ages. 相似文献