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181.
182.
化工园区开发建设项目具有建设内容复杂、建设范围大、建设周期长等特点,且不确定性强,产生污染物种类多、数量大,对周边区域的环境影响复杂,其规划环境影响评价应主要依据《开发区区域环境影响评价技术导则》编制。根据化工园区开发项目的环境影响特点,选址、功能区布局、产业规划及可持续发展能力分析作为化工园区规划环评中重点关注的问题,并给予重点评价。 相似文献
183.
Jung-Chen Huang William J. Mitsch Andrew D. Ward 《Journal of the American Water Resources Association》2010,46(5):957-971
Huang, Jung-Chen, William J. Mitsch, and Andrew D. Ward, 2010. Design of Experimental Streams for Simulating Headwater Stream Restoration. Journal of the American Water Resources Association (JAWRA) 1-15. DOI: 10.1111/j.1752-1688.2010.00467.x Abstract: Headwater streams flowing through agricultural fields in the midwestern United States have been extensively modified to accommodate subsurface drainage systems, resulting in deepened, straightened, and widened streams. To restore these headwater streams, partial or total reconstruction of channels is frequently attempted. There are different approaches to reconstructing the channel, yet there is little evidence that indicates which promises more success and there has been no experimental work to evaluate these approaches. This study designs three experimental channels – two-stage, self-design, and straightened channels – on a human-created swale at the Olentangy River Wetland Research Park, Columbus, Ohio, for long-term evaluation of headwater stream evolution after restoration. The swale receives a continuous flow of pumped river water from upstream wetlands. Using streamflow and stage data for the past 12 years, a channel-forming discharge of 0.18 m3/s was estimated from bankfull discharge, effective discharge, and recurrence interval. These stream channels, after construction, will be monitored to evaluate physical, chemical, and biological responses to different channels over a decade-long experiment. We hypothesize that the three stream restoration designs will eventually evolve to a similar channel form but with different time periods for convergence. Monitoring the frequency and magnitude of changes over at least 10 years is needed to document the most stable restored channel form. 相似文献
184.
Revenga JE Campbell LM Kyser K Klassen K Arribére MA Ribeiro Guevara S 《Chemosphere》2011,83(3):265-270
Silver (Ag) ions are among the most toxic metallic ions to aquatic biota. In southern Argentina, fish from Patagonian lakes have liver Ag concentrations [Ag] among the highest ever reported globally. Silver concentration in phytoplankton from Lake Moreno (1.82 ± 3.00 μg g−1 dry weight, DW) was found to be significantly higher than [Ag] in zooplankton (0.25 ± 0.13 μg g−1). Values in snails and decapods (0.60 ± 0.28 μg g−1 and 0.47 ± 0.03 μg g−1 respectively), were higher than in insect larvae (0.28 ± 0.39 μg g−1 for Trichoptera). We examined trophic transfer of Ag in the biota using stable nitrogen and carbon isotopes ratios (δ15N and δ13C respectively). Silver concentrations in the biota of Lake Moreno were not associated with any particular C source, as assessed by δ13C. Hepatic [Ag] significantly increased with trophic position, as measured by δ15N, within the brook trout sample set. Biodilution of Ag was observed between primary producers and small forage fish when whole body [Ag] was analyzed. Nevertheless, when considering whole food web biomagnification and hepatic [Ag] of top predator fish, a significant positive regression was found between [Ag] and trophic position, as measured by δ15N. The importance of species-specific and tissue-specific considerations to obtain more information on Ag trophodynamics than that usually presented in the literature is shown. To the best of our knowledge, this is the first study in assessing Ag trophodynamics and tissue-specific biomagnification in a whole freshwater food web. 相似文献
185.
We monitored nest boxes during 1997–1999 at Acadia National Park, Mt. Desert Island, ME and at an old-field site in Orono,
ME to determine mercury (Hg) uptake in tree swallow (Tachycineta bicolor) eggs, tissues, and food boluses. Also, in 1998–1999 we monitored nest boxes at Grove Pond and Plow Shop Pond at a U.S. Environmental
Protection Agency Superfund site in Ayer, MA. We recorded breeding success at all locations. On average among locations, total
mercury (THg) biomagnified 2 to 4-fold from food to eggs and 9 to 18-fold from food to feathers. These are minimum values
because the proportion of transferable methyl mercury (MeHg) of the THg in insects varies (i.e., 35%–95% of THg) in food boluses.
THg was highest in food boluses at Aunt Betty Pond at Acadia, whereas THg in eggs was highest at the Superfund site. A few
eggs from nests at each of these locations exceeded the threshold (i.e., 800–1,000 ng/g, wet wt.) of embryotoxicity established
for Hg. Hatching success was 88.9% to 100% among locations, but five eggs failed to hatch from 4 of the 11 clutches in which
an egg exceeded this threshold. MeHg in feathers was highest in tree swallows at Aunt Betty Pond and the concentration of
THg in bodies was related to the concentration in feathers. Transfer of an average of 80%–92% of the Hg in bodies to feathers
may have enhanced nestling survival. Residues of Hg in tissues of tree swallows in the Northeast seem higher than those of
the Midwest. 相似文献
186.
Nelson SJ Johnson KB Kahl JS Haines TA Fernandez IJ 《Environmental monitoring and assessment》2007,126(1-3):69-80
Precipitation and streamwater samples were collected from 16 November 1999 to 17 November 2000 in two watersheds at Acadia
National Park, Maine, and analyzed for mercury (Hg) and dissolved inorganic nitrogen (DIN, nitrate plus ammonium). Cadillac
Brook watershed burned in a 1947 fire that destroyed vegetation and soil organic matter. We hypothesized that Hg deposition
would be higher at Hadlock Brook (the reference watershed, 10.2 μg/m2/year) than Cadillac (9.4 μg/m2/year) because of the greater scavenging efficiency of the softwood vegetation in Hadlock. We also hypothesized the Hg and
DIN export from Cadillac Brook would be lower than Hadlock Brook because of elemental volatilization during the fire, along
with subsequently lower rates of atmospheric deposition in a watershed with abundant bare soil and bedrock, and regenerating
vegetation. Consistent with these hypotheses, Hg export was lower from Cadillac Brook watershed (0.4 μg/m2/year) than from Hadlock Brook watershed (1.3 μg/m2/year). DIN export from Cadillac Brook (11.5 eq/ha/year) was lower than Hadlock Brook (92.5 eq/ha/year). These data show that
∼50 years following a wildfire there was lower atmospheric deposition due to changes in forest species composition, lower
soil pools, and greater ecosystem retention for both Hg and DIN. 相似文献
187.
Peckenham JM Kahl JS Nelson SJ Johnson KB Haines TA 《Environmental monitoring and assessment》2007,126(1-3):97-104
Fall and spring streamwater samples were analyzed for total mercury (Hg) and major ions from 47 locations on Mount Desert
Island in Maine. Samples were collected in zones that were burned in a major wildfire in 1947 and in zones that were not burned.
We hypothesized that Hg concentrations in streamwater would be higher from unburned sites than burned watersheds, because
fire would volatilize stored Hg. The Hg concentrations, based on burn history, were not statistically distinct. However, significant
statistical associations were noted between Hg and the amount of wetlands in the drainage systems and with streamwater dissolved
organic carbon (DOC). An unexpected result was that wetlands mobilized more Hg by generating more DOC in total, but upland DOC was more efficient at transporting Hg because it transports more Hg per unit DOC. Mercury concentrations were higher in samples collected at lower elevations. Mercury was positively correlated with relative
discharge, although this effect was not distinguished from the DOC association. In this research, sample site elevation and
the presence of upstream wetlands and their associated DOC affected Hg concentrations more strongly than burn history. 相似文献
188.
Bank MS Burgess JR Evers DC Loftin CS 《Environmental monitoring and assessment》2007,126(1-3):105-115
We reviewed literature reporting both total and methylmercury from biota from Acadia National Park, Maine, USA. Our review
of existing data indicates that 1) mercury contamination is widespread throughout the Park’s various aquatic ecosystems; 2)
mercury pollution likely represents a moderate to high risk to biota inhabiting the Park; and 3) biota at all trophic levels
possess elevated concentrations of both total and methylmercury. Watershed fire history and the resulting post-fire forest
succession patterns are an important landscape attribute governing mercury cycling at Acadia National Park. Therefore, park
service personnel should consider these factors when planning and implementing Hg biomonitoring efforts. Additional baseline
funding from the National Park Service for Hg research and biomonitoring will likely be required in order to further evaluate
the spatial and temporal patterns of mercury contamination in the park’s biota.
An erratum to this article can be found at 相似文献
189.
Johnson KB Haines TA Kahl JS Norton SA Amirbahman A Sheehan KD 《Environmental monitoring and assessment》2007,126(1-3):55-67
Throughfall and bulk precipitation samples were collected for two watersheds at Acadia National Park, Maine, from 3 May to
16 November 2000, to determine which landscape factors affected mercury (Hg) deposition. One of these watersheds, Cadillac
Brook, burned in 1947, providing a natural experimental design to study the effects of forest type on deposition to forested
watersheds. Sites that face southwest received the highest Hg deposition, which may be due to the interception of cross-continental
movement of contaminated air masses. Sites covered with softwood vegetation also received higher Hg deposition than other
vegetation types because of the higher scavenging efficiency of the canopy structure. Methyl mercury (MeHg) deposition was
not affected by these factors. Hg deposition, as bulk precipitation and throughfall was lower in Cadillac Brook watershed
(burned) than in Hadlock Brook watershed (unburned) because of vegetation type and watershed aspect. Hg and MeHg inputs were
weighted by season and vegetation type because these two factors had the most influence on deposition. Hg volatilization was
not determined. The total Hg deposition via throughfall and bulk precipitation was 9.4 μg/m2/year in Cadillac Brook watershed and 10.2 μg/m2/year in Hadlock Brook watershed. The total MeHg deposition via throughfall and bulk precipitation was 0.05 μg/m2/year in Cadillac Brook watershed and 0.10 μg/m2/year in Hadlock Brook watershed. 相似文献
190.
J. Shaun Dustin A. Woodruff Miller 《Journal of the American Water Resources Association》2001,37(4):887-898
ABSTRACT: Increased visitation at Grand Teton National Park (GTNP) has raised concerns about impacts on surface water in the park. The purposes of this study are to perform a benchmark trophic state survey for comparison to future evaluations and to identify possible areas of concern. Four watershed regions based on geographic and geologic features were delineated for study. Six Alpine lakes, six Moraine lakes, three Valley lakes, and two Colter Bay lakes are evaluated. Lakes were sampled for total phosphorus (TP), chlorophyll‐a, and transparency. The water quality, as defined by trophic state, in the park is generally good. Oligotrophic to mesotrophic conditions were found in the Alpine and Moraine lakes and mesotrophic to eutrophic conditions were found in the Colter Bay and Valley lakes. High inflow TP concentrations in the park's northeast side may be due to the presence of natural geologic phosphate from the Phosphoria Formation. 相似文献