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151.
Başak K. Taşeli 《The Environmentalist》2007,27(3):315-327
Environmental pollution and degradation of ecosystems considerably affect the natural resources. The Turkish Government is
aware of the importance of the preservation of natural ecology and thereby the environmental conservation of many species
in their natural habitat. This paper provides critical assessments of the problems and possible solutions in the identification,
implementation and management of the Specially Protected Areas (SPAs) system by giving basic information about stakeholders
and their responsibilities that currently offer nature conservation in Turkey. The goals of the article are to analyze how
the SPAs interface with the local people, especially the villagers who have dwelt there before SPA designation and how people-SPA
conflicts resolved; to show how effective the SPA conservation objectives have been; to outline the significance of informing
and empowering people in nature conservation for the protected area management and to show the importance of planning at all
levels during protection of the natural, archeological and cultural values of the SPAs. 相似文献
152.
Ben A. Minteer Elizabeth A. Corley 《Journal of Agricultural and Environmental Ethics》2007,20(4):307-333
Few disputes in the annals of US environmentalism enjoy the pedigree of the conservation-preservation debate. Yet, although
many scholars have written extensively on the meaning and history of conservation and preservation in American environmental
thought and practice, the resonance of these concepts outside the academic literature has not been sufficiently examined.
Given the significance of the ideals of conservation and preservation in the justification of environmental policy and management,
however, we believe that a more detailed analysis of the real-world use and understanding of these ideas is needed. In this
paper, we describe the results of a qualitative, semantic study of the concepts of conservation and preservation undertaken
in the context of the Chattahoochee National Forest (CNF), located in northern Georgia (USA). Thirty in-depth interviews were
conducted with scientists and north Georgia residents either interested or involved in the future management of the forest.
Respondents were asked to define conservation and preservation in their own words and to indicate which approach they felt
was more appropriate for the management of the CNF. Qualitative content analysis was used to elicit a set of recurring themes
for each foundational concept. Taken together, these themes help to flesh out the meaning of conservation and preservation
for citizens and scientists today, and illustrate the evolving nature of two of the more significant and venerable ideas animating
US environmental policy and management. 相似文献
153.
The microbiological and physico-chemical characteristics of the drinking water supplied by the Central Borehole at the University
of Benin, Ugbowo Campus were investigated. The investigation entailed assessment of the pH, turbidity, total suspended solids,
total dissolved solids, dissolved oxygen, temperature, salinity, conductivity, nitrate, nitrite, phosphate, sulphate, chloride,
N-nitroso compounds, cadmium, chromium, nickel, lead, zinc, manganese, iron, coliform count, BOD5 and COD of the water at the Central Borehole and at ten residential quarters. The assessment indicated that the water was
fit for drinking and other domestic applications. Results were also compared with WHO, EU and Nigeria FEPA standards. The
results showed that the pH values of the water (5.01–5.86) and total coliform count (1–2/100 ml) expressed as MPN were outside
the limits set by the WHO, EU and FEPA. The data also showed that the other water quality parameters assessed were within
WHO, EU and FEPA permissible limits. The results of ANOVA showed that significant changes occurred during distribution. 相似文献
154.
The optimized BCR sequential extraction procedure (proposed by the Standards, Measurements and Testing Programme (SM&T) of
the European Union) was applied to seven topsoil samples from refuse dump sites for the determination of Cu, Zn, Ni, Pb and
Cd. The metals were partitioned into four operationally defined chemical fractions: acid extractable, reducible, oxidizable
and residual, and analysed using flame atomic absorption spectrophotometry, FAAS.
The results were compared with total metal concentrations obtained using HNO3, HClO4 and HF digestion procedures. Results for total metal analysis ranged from - 15.55 to 43.45 for Cu, 37.15 to 222.35 for Zn,
5.15 to 12.10 for Ni, 10.30 to 93.05 for Pb and 0.35 to 3.75 for Cd in μgg−1 dry weight. The results of the partitioning study showed that zinc prevailed in the more soluble fractions and was distributed
between the acid-extractable (32.4%) and the reducible (40.3%) fractions, whereas Pb was distributed mainly in the reducible
fraction. Copper and nickel were predominantly associated with the reducible and residual fractions - 53.4, 33.3 and 51.1,
24.1% respectively. The ranking of the four fractions for the partitioning of cadmium was: reducible > residual > oxidizable
> acid extractable. The percentage recovery for all metals when comparing total metal concentration with the fractional sum
of the optimized BCR procedure, were of the order: Zn(93%) > Pb(83%) > Cu(78) > Cd > (68%) > Ni(63%). 相似文献
155.
Marko S. Markov 《The Environmentalist》2007,27(4):465-475
Magnetic and electromagnetic fields are now recognized by the 21st century medicine as real physical entities that promise
the healing of various health problems, even when conventional medicine has failed. Today magnetotherapy provides a non-invasive,
safe, and easy method to directly treat the site of injury, the source of pain and inflammation, and other types of diseases
and pathologies. Millions of people worldwide have received help in treatment of musculoskeletal system, as well as pain relief.
Pulsed electromagnetic fields are one important modality in magnetotherapy and recent technological innovations, such as Curatron
pulsed electromagnetic field devices, offer excellent, state of the art computer controlled therapy system. In this article
the development, state of the art and future of pulsed electromagnetic field therapy are discussed. 相似文献
156.
Correlating turbulent burning velocity to turbulence intensity and basic flame parameters-like laminar burning velocity for dust air mixtures is not only a scientific challenge but also of practical importance for the modelling of dust flame propagation in industrial facilities and choice of adequate safety strategy. The open tube method has been implemented to measure laminar and turbulent burning velocities at laboratory scale for turbulence intensities in the range of a few m/s. Special care has been given to the experimental technique so that a direct access to the desired parameters was possible minimising interpretation difficulties. In particular, the flame is propagating freely, the flame velocity is directly accessible by visualisation and the turbulence intensity is measured at the flame front during flame propagation with special aerodynamic probes. In the present paper, those achievements are briefly recalled. In addition, a complete set of experiments for diametrically opposed dusts, starch and aluminium, has been performed and is presented hereafter. The experimental data, measured for potato dust air mixtures seem to be in accordance with the Bray Gülder model in the range of 1.5 m/s<u′<3.5 m/s. For a further confirmation, the measurement range has been extended to lower levels of turbulence of u′<1.5 m/s. This could be achieved by changing the mode of preparation of the dust air mixture. In former tests, the particles have been injected into the tube from a pressurised dust reservoir; for the lower turbulence range, the particles have been inserted into the tube from above by means of a sieve–riddler system, and the turbulence generated from the pressurised gas reservoir as before. For higher levels of turbulence, aluminium air mixtures have been investigated using the particle injection mode with pressurised dust reservoir. Due to high burning rates much higher flame speeds than for potato dusts of up to 23 m/s have been obtained. 相似文献
157.
158.
A. M. Rusanov 《Russian Journal of Ecology》2012,43(1):33-39
Results are presented that have been obtained in studies on the effect of forests growing in the steppe zone on the conditions
of formation and qualitative and quantitative composition of organic matter and on the properties of humus in chernozem soils
of neighboring biogeocenoses. 相似文献
159.
Richard C. Foltz 《Journal of Agricultural and Environmental Ethics》2007,20(6):533-542
160.
Quantification and reduction of erroneous differences between images in remote sensing 总被引:1,自引:0,他引:1
The reliability of image data, along with the difficulty of accurately comparing images acquired at different times or from
different sensors, is a generic problem in remote sensing. Measurement repeatability errors occur frequently and can substantially
reduce the system’s ability to reliably quantify real spectral and spatial change in a target. This paper outlines methodologies
for quantifying and reducing erroneous differences between monochrome and multispectral or hyperspectral images. [Each of
these image types is acquired by an instrument that collects light photons across a variable range of the electromagnetic
spectrum (often referred to as an image band). The hyperspectral image is often referred to as a hyperspectral cube with XY
spatial dimensions and many Z bands (spectral demotions)]. In this paper, we specifically discuss the Pixel Block Transform
(PBT), the Spectral Averaging Transform (SAT), and the Wavelet Transform (WAVEL). We briefly address sensor fusion. Results
indicate that the PBT is a powerful cross-noise and repeatability error reducing tool, applicable to monochrome, multispectral,
and hyperspectral images. The SAT is as powerful as the PBT in reducing error but is suitable only for hyperspectral imagery.
WAVEL can reduce some of the finer scale noise, but it is not as powerful in reducing cross-noise as PBT or SAT and it requires
some trial and error for selecting the appropriate wavelet function. It is important that those involved in developing statistically
sound relationships between remotely sensed imagery and other data sources understand the problems and their solutions to
prevent wasting time or developing relationships that are statistically insignificant or unstable, or that lead to faulty
conclusions. 相似文献