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621.
Andrea Kölzsch Thomas K. Lameris Gerhard J. D. M. Müskens Kees H. T. Schreven Nelleke H. Buitendijk Helmut Kruckenberg Sander Moonen Thomas Heinicke Lei Cao Jesper Madsen Martin Wikelski Bart A. Nolet 《Conservation Letters》2023,16(1):e12927
In the present Anthropocene, wild animals are globally affected by human activity. Consumer fireworks during New Year (NY) are widely distributed in W-Europe and cause strong disturbances that are known to incur stress responses in animals. We analyzed GPS tracks of 347 wild migratory geese of four species during eight NYs quantifying the effects of fireworks on individuals. We show that, in parallel with particulate matter increases, during the night of NY geese flew on average 5–16 km further and 40–150 m higher, and more often shifted to new roost sites than on previous nights. This was also true during the 2020–2021 fireworks ban, despite fireworks activity being reduced. Likely to compensate for extra flight costs, most geese moved less and increased their feeding activity in the following days. Our findings indicate negative effects of NY fireworks on wild birds beyond the previously demonstrated immediate response. 相似文献
622.
Lasse Wallquist Vivianne H.M. Visschers Michael Siegrist 《International Journal of Greenhouse Gas Control》2009,3(5):652-657
Laypeople's acceptance and perception of Carbon Dioxide Capture and Storage (CCS) can have an influence on its political feasibility. It is important, therefore, to study how laypeople perceive CCS and which cognitions they hold with respect to this technique. We conducted in-depth interviews with laypeople (N = 16) to explore their mental concepts of CCS. Little knowledge about CCS was detected among laypeople. We also found that laypeople fear that a deployment of CCS could create incentives that would hinder a sustainable development of the energy economy. A misunderstanding of the concepts of hydro- and geostatic pressure, as well as a lack of knowledge about the physical–chemical properties of carbon dioxide seemed to trigger fundamental rejection of CCS among some laypeople. This qualitative study identifies concepts that underlie CCS perception, and these should be objects of future studies. We provide some suggestions for risk management and communication about CCS. 相似文献
623.
Spatiotemporal variability of wet atmospheric nitrogen deposition to the Neuse River Estuary, North Carolina 总被引:1,自引:0,他引:1
Excessive nitrogen (N) loading to N-sensitive waters such as the Neuse River estuary (North Carolina) has been shown to promote changes in microbial and algal community composition and function (harmful algal blooms), hypoxia and anoxia, and fish kills. Previous studies have estimated that wet atmospheric deposition of nitrogen (WAD-N), as deposition of dissolved inorganic nitrogen (DIN: NO3-, NH3/NH4+) and dissolved organic nitrogen, may contribute at least 15% of the total externally supplied or "new" N flux to the coastal waters of North Carolina. In a 3-yr study from June 1996 to June 1999, we calculated the weekly wet deposition of inorganic and organic N at eleven sites on a northwest-southeast transect in the watershed. The annual mean total (wet DIN + wet organics) WAD-N flux for the Neuse River watershed was calculated to be 956 mg N/m2/yr (15026 Mg N/yr). Seasonally, the spring (March-May) and summer (June-August) months contain the highest total weekly N deposition; this pattern appears to be driven by N concentration in precipitation. There is also spatial variability in WAD-N deposition; in general, the upper portion of the watershed receives the lowest annual deposition and the middle portion of the watershed receives the highest deposition. Based on a range of watershed N retention and in-stream riverine processing values, we estimate that this flux contributes approximately 24% of the total "new" N flux to the estuary. 相似文献
624.
The concept of intrinsic value and transgenic animals 总被引:1,自引:0,他引:1
H. Verhoog 《Journal of Agricultural and Environmental Ethics》1992,5(2):147-160
The creation of transgenic animals by means of modern techniques of genetic manipulation is evaluated in the light of different interpretations of the concept of intrinsic value. The zoocentric interpretation, emphasizing the suffering of individual, sentient animals, is described as an extension of the anthropocentric interpretation. In a biocentric or ecocentric approach the concept of intrinsic value first of all denotes independence of humans and a non-instrumental relation to animals. In the zoocentric approach of Bernard Rollin, genetic engineering is seen as a morally neutral tool, as long as the animal does not suffer as a result of it. Robert Colwell who defends an ecocentric ethic, makes a sharp distinction between wild animals and domesticated animals. Genetic manipulation of wild species is a serious moral issue, in contrast to genetic manipulation of domesticated species which is no problem at all for Colwell. Both authors do not take the species-specific nature (or telos) of domesticated animals seriously. When domestication is seen as a process between the two poles of the wild animal and the human construct (which can be patented), the technique of genetic manipulation can only be seen as a further encroachment upon the intrinsic value of animals. At the level of molecular biology, the concept of an animal's telos loses its meaning. 相似文献
625.
626.
Vegetation stress detection through chlorophyll a + b estimation and fluorescence effects on hyperspectral imagery 总被引:2,自引:0,他引:2
Zarco-Tejada PJ Miller JR Mohammed GH Noland TL Sampson PH 《Journal of environmental quality》2002,31(5):1433-1441
Physical principles applied to remote sensing data are key to successfully quantifying vegetation physiological condition from the study of the light interaction with the canopy under observation. We used the fluorescence-reflectance-transmittance (FRT) and PROSPECT leaf models to simulate reflectance as a function of leaf biochemical and fluorescence variables. A series of laboratory measurements of spectral reflectance at leaf and canopy levels and a modeling study were conducted, demonstrating that effects of chlorophyll fluorescence (CF) can be detected by remote sensing. The coupled FRT and PROSPECT model enabled CF and chlorophyll a + b (Ca + b) content to be estimated by inversion. Laboratory measurements of leaf reflectance (r) and transmittance (t) from leaves with constant Ca + b allowed the study of CF effects on specific fluorescence-sensitive indices calculated in the Photosystem I (PS-I) and Photosystem II (PS-II) optical region, such as the curvature index [CUR; (R675.R690)/R2(683)]. Dark-adapted and steady-state fluorescence measurements, such as the ratio of variable to maximal fluorescence (Fv/Fm), steady state maximal fluorescence (F'm), steady state fluorescence (Ft), and the effective quantum yield (delta F/F'm) are accurately estimated by inverting the FRT-PROSPECT model. A double peak in the derivative reflectance (DR) was related to increased CF and Ca + b concentration. These results were consistent with imagery collected with a compact airborne spectrographic imager (CASI) sensor from sites of sugar maple (Acer saccharum Marshall) of high and low stress conditions, showing a double peak on canopy derivative reflectance in the red-edge spectral region. We developed a derivative chlorophyll index (DCI; calculated as D705/D722), a function of the combined effects of CF and Ca + b content, and used it to detect vegetation stress. 相似文献
627.
A. Wieraszko Z. Ahmed J. Armani N. Maqsood S. Philips H. Raja 《The Environmentalist》2005,25(2-4):145-155
Summary The influence of pulsed magnetic fields (PMF) on the properties of nervous tissue was investigated. Hippocampal slices or
synaptosomes obtained from hippocampal tissue were used as model systems. The amplitude of potentials recorded in vitro from one of the hippocampal pathways (Schaffer collaterals that use glutamate as a neurotransmitter) was employed as a measure
of the influence of magnetic fields on synaptic efficiency. The synaptic glutamate turnover and radioactive calcium accumulation
were used as markers of the PMF influence on biochemistry of synaptic mechanisms. The exposure of hippocampal slices for 30
min to PMF amplified evoked potentials. While the frequency of 0.16 Hz exerted the strongest effect, lower (0.01, 0.07, 0.03
Hz) and higher (0.5 Hz) frequencies were much less effective. The enhancement of the neuronal excitability was correlated
with significant increase in the neuronal spontaneous activity mediated by electrical synapses. The PMF-induced changes in
the excitability of the tissue were accompanied by an increase in the synaptic turnover of glutamate. The release of radioactive
D-Aspartate (a glutamate analog used as a marker for glutamate turnover) from the slices, and its uptake by synaptosomes were
enhanced, and reduced respectively, following the stimulation with pulsed magnetic fields. The frequency which was the most
efficient in amplification of evoked potentials (0.16 Hz) was also the most effective in the modulation of the release and
uptake processes. The PMF-induced changes in neurotransmitter turnover coincided with an increase in 45Ca2+ accumulation observed in hippocampal slices exposed to PMF. 相似文献
628.
629.
Reclamation of wastes contaminated by copper,lead, and zinc 总被引:18,自引:0,他引:18
M. H. Wong 《Environmental management》1986,10(6):707-713
Waste materials containing toxic levels of copper, lead, and zinc, such as mine and smelter wastes, present difficult conditions for the establishment of vegetation. This article reviews the many attempts which have been made to reclaim these wastes. Inert wastes from mining and quarrying operations, such as slate quarry waste and certain colliery shales, seem to be good materials for reclaiming wastes contaminated by copper, lead, and zinc. Organic wastes, such as sewage sludge and domestic refuse, may provide only a temporary visual improvement and stabilization of the toxic materials.Nontolerant plant materials may often be planted directly on modern waste materials, which are less toxic than they were in the past. However, tolerant plant materials are needed for revegetating waste materials produced by early and more primitive extraction methods. 相似文献
630.
Land treatment of municipal wastewater effluent is a proven method for augmenting freshwater resources and avoiding direct nutrient discharges to surface waters. We assessed changes in soil test phosphorus (P) of the Ap horizon of cropped fields continuously irrigated for 26 yr with secondary effluent from the Penn State University wastewater treatment plant. For annual P additions averaging 97 kg P ha(-1), Mehlich-3 P (M3P) response in the 0- to 20-cm surface soil (initially < 20 mg kg(-1)) was represented by two lines. For the first 12 yr of irrigation, soil test P increased, with 14.5 kg P ha(-1) needed to increase M3P by 1 mg P kg(-1). After the initial buildup, M3P maintained a quasi-steady-state value of approximately 110 mg kg(-1). Over time, the surface soil equilibrium P concentration at zero sorption increased markedly (from < 1 to 5.5 mg P L(-1)), and extractable aluminum (Al) decreased significantly (P < 0.001). Speciation modeling using Visual MINTEQ suggests complexation of Al by dissolved organic carbon at site pH conditions. Loss of Al from the surface layer lowered its P-sorbing capacity, causing added effluent-P to move into the subsoil. Results suggest that current management practices can continue for many years without exceeding the surface soil M3P environmental threshold (200 mg kg(-1)) used in state P-based nutrient policies. 相似文献