鄂尔多斯TSP和PM_(10)中有机氯农药的分布与来源

于2012年5月在内蒙古鄂尔多斯的东胜、纳林希里、棋盘井和上湾等4个采样点连续采集大气TSP和PM10样品,利用GC-MS分析了其中18种OCPs。结果表明:除了硫丹Ⅱ、硫丹Ⅰ和α-HCH未检出,β-HCH部分检出以外,其余14种OCPs均有100%检出。鄂尔多斯东胜、纳林希里、棋盘井和上湾TSP中∑OCPs浓度依次为2.63、9.85、5.09和6.22ng/m3;在PM10中为2.13、8.74、4.84和6.77ng/m3。∑OCPs中比重超过15%的有ADs、HCs和DDTs。TSP中∑OCPs浓度基本高于PM10中浓度,并且它们存在较好的正相关,相关系数r达到0.8846。污染源分析表明,纳林希里HCHs、CDs和DDTs可能均有外源输入。     

Estimating the number of active and successful bald eagle nests:an application of the dual frame method

Monitoring the number of animals in a wildlife population is an important task. In this paper, we estimate the number of active and successful bald eagle nests in a specific region using dual frame sampling techniques. The dual frame method combines independent samples from an incomplete list frame and an area frame that is assumed to be complete. Hartley's screening estimator is used to combine sample information from both frames. This methodology will be useful for monitoring any wildlife population where the breeding individuals have highly visible nesting territories which tend to be stable over many years.     

Mercury in Tree Swallow Food, Eggs, Bodies, and Feathers at Acadia National Park, Maine, and an EPA Superfund Site, Ayer, Massachusetts

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.     

Controls on Mercury and Methylmercury Deposition for Two Watersheds in Acadia National Park, Maine

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.     

Landscape Controls on Mercury in Streamwater at Acadia National Park, USA

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.     

拟除虫菊酯农药的微波辅助无极汞灯下的降解机理研究

在水溶液中,以微波辅助无极汞灯(Microwave-Assisted Eletrodeless Discharge Mercury Lamp,MW-EDML)降解氯氰菊酯、甲氰菊酯和功夫菊酯等3种拟除虫菊酯农药(Synthetic pyrethroids,SPs),采用固相萃取(Solid Phase Extraction,SPE)富集后,用GC-MS鉴定降解产物,并根据降解产物重点探讨了SPs的降解机理。3种SPs的主要降解产物有6种,其降解途径有:酯键水解、氰基水解、脱羧、醚键断裂、氧化、苯环的羟基化以及与溶剂反应等。实验结果还表明:MW-EDML是个高效、简便的降解SPs类农药手段,可应用于其他有机污染物的降解过程。     

Aircraft and road traffic noise exposure and children's mental health

There have been few studies examining noise and psychological disorders in children and the results are equivocal. The objective of this study was to examine exposure–effect relationships between aircraft and road traffic noise exposure and children's mental health. We conducted a cross-national, cross-sectional study assessing 2844 pupils, aged 9–10, from 89 schools around three major airports in the Netherlands, Spain and United Kingdom matched within country for socio-economic position. We selected children on the basis of exposure to external aircraft and road traffic noise exposure. The Strengths and Difficulties Questionnaire (SDQ) assessed child mental health, including emotional problems, conduct disorder, hyperactivity, peer problems and prosocial behaviour. Aircraft noise exposure was significantly associated with an increased score on the hyperactivity subscale (pooled B estimate 0.013 CI 0.007–0.019) after full adjustment. Road traffic noise was significantly associated with lower scores on the conduct problems subscale maintained after full adjustment (pooled B estimate 0.010 95%CI −0.020 to −0.001). There was no association between either aircraft or road traffic noise exposure and the SDQ total score. The hyperactivity results have been found in a previous UK study and may indicate that high aircraft noise exposure exacerbates hyperactivity symptoms in children although this finding requires further replication.     

Mass Balances of Mercury and Nitrogen in Burned and Unburned Forested Watersheds at Acadia National Park, Maine, USA

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.     

Mortality, growth, swimming activity and gill morphology of brook trout (Salvelinus fontinalis) and Atlantic salmon (Salmo salar) exposed to low pH with and without aluminum

Measurements were made of mortality, growth, swimming activity, and gill morphology of young-of-the-year brook trout (Salvelinus fontinalis) and Atlantic salmon (Salmo salar), exposed for 30 days to pH 5.6 +/- 0.5 (mean +/- 1 standard deviation) with and without addition of 107 +/- 57 microg liter(-1) exchangeable (labile monomeric) aluminum. The experiment was conducted in artificial stream channels adjacent to a natural stream and subject to daily and seasonal changes in temperature, light, and chemical conditions. There were no differences in survival or growth for brook trout in any treatment; Atlantic salmon survival and growth were significantly decreased in the acid + Al treatment. Scanning electron microscopy showed no damage to gills of either species in the acid treatments, but the acid + Al treatment caused slight swelling of brook trout gills near the filament tips and significant swelling and fusion of secondary lamellae of Atlantic salmon gills. The acid treatment increased swimming activity in brook trout, but both the acid and acid + Al treatments reduced activity in Atlantic salmon.     

Divergent foraging strategies of three co-occurring north Pacific flatfishes

Despite facing similar constraints imposed by the environment, significant variation in life history traits frequently exists among species generally considered to comprise a single ecological guild. For juvenile flatfishes, constraints on foraging activity include variation in light and prey availability, as well as predation risk. This paper describes the visual constraints on, and divergent foraging strategies of three co-occurring north Pacific flatfish species, northern rock sole (Lepidopsetta polyxystra), Pacific halibut (Hippoglossus stenolepis), and English sole (Pleuronectes vetulus). Visual foraging abilities measured in the laboratory decreased rapidly below 10⁻⁴ μmol photons·m⁻² s⁻¹, and were similar among species. Despite similar sensory constraints, field sampling in August 2004 at a Kodiak Island nursery site (Holiday Beach, 57^o41.2′ N, 152^o27.7′ W) identified species differences in diets, diel foraging patterns, and within-nursery depth distributions. Northern rock sole and English sole fed primarily on bivalve siphons and polychaetes, whereas mysids dominated the diets of Pacific halibut. Northern rock sole were geographically the most widespread but feeding activity was temporally restricted to the dusk period. Pacific halibut were rare in shallow depths (<5 m) and fed most intensively prior to dusk. English sole fed throughout the daylight hours and were abundant only in the shallowest (<5 m) habitats. These differences in diets, foraging times, and habitat use appear related to previously documented species-specific behavioral characteristics as well as general spatial (increasing with depth) and temporal (increasing during foraging activity) variations in predation risk. At one extreme, the conservative behavioral strategy of northern rock sole may permit use of a broader range of foraging habitats, whereas English sole may be restricted to shallow water by limited behavioral responses to predation threat. These observations demonstrate that the appearance of habitat partitioning is not due to differences in sensory ability, but reflects multi-faceted, species-specific responses to the ecological tradeoffs between foraging and predation risks.