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711.
712.
Southern Chile encompasses one of the most extensive fjord regions of the world, the Patagonia, currently exposed to natural
and anthropogenic perturbations. These fjord ecosystems provide important services to humans, which have not been adequately
measured and valued. As a consequence, ecosystem services are commonly ignored in public policy design and in the evaluation
of development projects. Here we tackle questions that are highly relevant for the nation’s development, namely (1) understanding
fjord functioning, and (2) developing management strategies based on ecosystem services, in order to secure simultaneous and
adequate use of these ecosystems which area influenced by ecological (e.g., biogeochemical) and productive (e.g., aquaculture,
fisheries) processes. We also seek to strengthen the analysis of fjord ecosystem value from the economical (including coastal
zoning), socio-cultural, institutional, and governmental points of view. In addition, the investigation of current and future
effects of climate change on this large region offers a unique opportunity to understand the social and economic consequences
of a global phenomenon at local to regional scales. Biogeochemical and socio-economic models will be used to simulate future
scenarios under a gamut of management options. 相似文献
713.
Joseph N.T. Darbah Mark E. Kubiske Katre Kets Anu Sober David F. Karnosky 《Environmental pollution (Barking, Essex : 1987)》2010,158(4):983-19373
Photosynthetic acclimation under elevated carbon dioxide (CO2) and/or ozone (O3) has been the topic of discussion in many papers recently. We examined whether or not aspen plants grown under elevated CO2 and/or O3 will acclimate after 11 years of exposure at the Aspen Face site in Rhinelander, WI, USA. We studied diurnal patterns of instantaneous photosynthetic measurements as well as A/Ci measurements monthly during the 2004-2008 growing seasons. Our results suggest that the responses of two aspen clones differing in O3 sensitivity showed no evidence of photosynthetic and stomatal acclimation under either elevated CO2, O3 or CO2 + O3. Both clones 42E and 271 did not show photosynthetic nor stomatal acclimation under elevated CO2 and O3 after a decade of exposure. We found that the degree of increase or decrease in the photosynthesis and stomatal conductance varied significantly from day to day and from one season to another. 相似文献
714.
Erica Donner Kris Broos Diane Heemsbergen Mike J. McLaughlin Mark E. Hodson 《Environmental pollution (Barking, Essex : 1987)》2010,158(1):339-345
As zinc (Zn) is both an essential trace element and potential toxicant, the effects of Zn fixation in soil are of practical significance. Soil samples from four field sites amended with ZnSO4 were used to investigate ageing of soluble Zn under field conditions over a 2-year period. Lability of Zn measured using 65Zn radioisotope dilution showed a significant decrease over time and hence evidence of Zn fixation in three of the four soils. However, 0.01 M CaCl2 extractions and toxicity measurements using a genetically modified lux-marked bacterial biosensor did not indicate a decrease in soluble/bioavailable Zn over time. This was attributed to the strong regulatory effect of abiotic properties such as pH on these latter measurements. These results also showed that Zn ageing occurred immediately after Zn spiking, emphasising the need to incubate freshly spiked soils before ecotoxicity assessments. 相似文献
715.
E. Lombi D.P. Stevens M.J. McLaughlin 《Environmental pollution (Barking, Essex : 1987)》2010,158(6):2110-2116
Water treatment residuals (WTRs) are produced by the treatment of potable water with coagulating agents. Beneficial recycling in agriculture is hampered by the fact that WTRs contain potentially toxic contaminants (e.g. copper and aluminium) and they bind phosphorus strongly. These issues were investigated using a plant bioassay (Lactuca sativa), chemical extractions and an isotopic dilution technique. Two WTRs were applied to an acidic and a neutral pH soil at six rates. Reductions in plant growth in amended soils were due to WTR-induced P deficiency, rather than Al or Cu toxicity. The release of potentially toxic Al from WTRs was found to be mitigated by their alkaline nature and pH buffering capacity. However, acidification of WTRs was shown to release more soluble Al than soil naturally high in Al. Copper availability was relatively low in all treatments. However, the lability of WTR-Cu increased when the WTR was applied to the soil. 相似文献
716.
Grahovac ZM Mitić SS Pecev ET Pavlović AN 《Journal of environmental science and health. Part. B》2010,45(8):783-789
In the present study, a new sensitive and simple kinetic-spectrophotometric method for the determination of the insecticide diflubenzuron [1-(4-chlorophenyl)-3-(2,6-diflubenzoil)urea] is proposed. The method is based on the inhibited effect of diflubenzuron on the oxidation of sulphanilic acid (SA) by hydrogen peroxide in phosphate buffer in presence Cu(II) ion. Diflubenzuron was determined with linear calibration graph in the interval from 0.31 to 3.1 μg mL?1 and from 3.1 to 31.0 μg mL?1. The optimized conditions yielded a theoretical detection limit of 0.18 μg mL?1 corresponding to 0.036 mg kg(-1)mushroom sample based on the 3S(b) criterion. The RSD is 5.03-1.83 % and 2.81-0.71 % for the concentration interval of diflubenzuron 0.31-3.1 μg mL?1 and 3.1-31.0 μg mL?1, respectively. The reaction was followed spectrophotometrically at 370 nm. The kinetic parameters of the reaction are reported, and the rate equations are suggested. The developed procedure was successfully applied to the rapid determination of diflubenzuron in spiked mushroom samples of different mushroom species. The HPLC method was used like a comparative method to verify results. 相似文献
717.
718.
Short-term increases in soil solution nitrate (NO3−) concentration are often observed after forest harvest, even in N-limited systems. We model NO3− leaching below the rooting zone as a function of site productivity. Using national forest inventories and published estimates of N attenuation in rivers and the riparian zone, we estimate effects of stem-only harvesting on NO3− leaching to groundwater, surface waters and the marine environment. Stem-only harvesting is a minor contributor to NO3− pollution of Swedish waters. Effects in surface waters are rapidly diluted downstream, but can be locally important for shallow well-waters as well as for the total amount of N reaching the sea. Harvesting adds approximately 8 Gg NO3-N to soil waters in Sweden, with local concentrations up to 7 mg NO3-N l−1. Of that, ∼3.3 Gg reaches the marine environment. This is ∼3% of the overall Swedish N load to the Baltic. 相似文献
719.
Miriam Hampel Esteban Alonso Irene Aparicio James E. Bron Juan Luis Santos John B. Taggart Michael J. Leaver 《Environmental science and pollution research international》2010,17(4):917-933
Background, aim, and scope
Pharmaceuticals are emerging pollutants widely used in everyday urban activities which can be detected in surface, ground, and drinking waters. Their presence is derived from consumption of medicines, disposal of expired medications, release of treated and untreated urban effluents, and from the pharmaceutical industry. Their growing use has become an alarming environmental problem which potentially will become dangerous in the future. However, there is still a lack of knowledge about long-term effects in non-target organisms as well as for human health. Toxicity testing has indicated a relatively low acute toxicity to fish species, but no information is available on possible sublethal effects. This study provides data on the physiological pathways involved in the exposure of Atlantic salmon as representative test species to three pharmaceutical compounds found in ground, surface, and drinking waters based on the evaluation of the xenobiotic-induced impairment resulting in the activation and silencing of specific genes. 相似文献720.