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31.
Jennifer E. Price Carl E. Zipper Jess W. Jones Christopher T. Franck 《Journal of the American Water Resources Association》2014,50(4):837-858
The Clinch River, in eastern United States, supports a diverse freshwater fauna including endangered mussels. Although mussel populations are stable in the Clinch's northeastern Tennessee segment, long‐term declines have been documented upstream in Virginia. We analyzed water and sediment quality data collected by government agencies from the 1960s through 2013 in an effort to inform current management. The river was divided into sections considering data availability and major tributaries. We tested for spatial differences among river sections and for temporal trends, and compared measured values to potentially protective levels if available. Ammonia concentrations approaching and exceeding protective levels were recorded, most often during the 1970s and 1980s in upstream sections. Sediment metals occurred at levels potentially causing biological effects, mainly during the 1980s and 1990s. In the 2000s, water‐column metals have been well below protective levels for general aquatic life. Dissolved solids (DS) increased in most river sections over the study period but mussel‐specific protective levels are not known. Analysis of water pH, total N, and total P did not generate conservation concern. Enhanced monitoring for sediment metals, water‐column metals, and ionic composition of DS; closer alignment of agency water monitoring practices in the two states; and research to determine biological effects of DS at current and anticipated levels can aid future conservation management. 相似文献
32.
Brad D. Wolaver Cassandra E. Cook David L. Sunding Stephen F. Hamilton Bridget R. Scanlon Michael H. Young Xianli Xu Robert C. Reedy 《Journal of the American Water Resources Association》2014,50(5):1081-1101
Texas water resources, already taxed by drought and population growth, could be further stressed by possible listings of endangered aquatic species. This study estimated potential economic impacts of environmental flows (EFs) for five freshwater unionid mussels in three Central Texas basins (Brazos, Colorado, and Guadalupe‐San Antonio Rivers) that encompass 36% of Texas (~246,000 km2). A water availability model projected reductions in water supply to power, commercial and industrial, municipal, and agriculture sectors in response to possible EFs for mussels. Single‐year economic impacts were calculated using publicly available data with and without water transfers. Benefits of EFs should also be assessed, should critical habitat be proposed. Potential economic losses were highest during droughts, but were nominal (<$1 M) in wetter years — even with high EFs. Reduced supplies to San Antonio area power plants caused worst‐case impacts of a single‐year shutdown up to $107 million (M) during drought with high EFs. For other sectors in the study area, water transfers reduced worst‐case losses from $80 to $11 M per year. Implementing innovative water management strategies such as water markets, conjunctive use of surface water and groundwater, aquifer storage and recovery could mitigate economic impacts if mussels — or other widely distributed aquatic species — were listed. However, approaches for defining EFs and strategies for mitigating economic impacts of EFs are needed. 相似文献
33.
Mendoza G Gutierrez L Pozo-Gallardo K Fuentes-Rios D Montory M Urrutia R Barra R 《Environmental science and pollution research international》2006,13(1):67-74
- DOI: http://dx.doi.org/10.1065/espr2006.01.011
Goal, Scope and Background Chile signed the Stockholm Convention, which establishes measures to reduce or eliminate Persistent Organic Pollutants (POPs)
release into the environment, including the prohibition of their use and reduction of secondary products release, as well
as management related with waste treatment. Among POPs, PCBs are a family of 209 compounds that differ in chlorine level and
position. These substances present a wide variability in their physicochemical properties such as vapor pressure, water solubility
and partition coefficients that determine their behavior and mobility within the different environmental compartments. In
Chile, as in other countries, the use of these compounds were and continue to occur in diverse industrial applications such
as dielectric fluid in transformers and condensers, with a use in Chile of approximately 550,000 L. A sampling of bivalves
was performed during the years 2000-2002 in order to obtain information on the spatial distribution of the PCB levels for
the length of the long Chilean coast (180–540 South latitude, 4,200 km), contributing in this way to a better understanding
of the PCB trend and eventual fractionation along latitudinal gradients in Chile, using as the bivalve Perumytilus purpuratus
('Chorito Maico') bioindicator.
Methods The marine bivalves Perumytilus purpuratus were collected in 16 localities in northern and southern Chile. All samples were
lyophilized, and PCBs (51 congeners) were extracted in a Soxhlet system (24 h) with n-hexane. Samples were cleaned in florisil
and analyzed by GC-ECD. Blanks, certified reference materials and standards were processed along with the samples.
Results and Discussion The results obtained for P. purpuratus indicate a congeneric distribution profile associated to a latitudinal gradient, and
the statistical analysis of the congeneric composition of the PCBs indicated five groups in relation to the molecular weight
(number of chlorines), where the lighter congeners were observed in areas corresponding to high latitudes with total PCB values
of 298 ng/g dry weight.
Conclusion P. purpuratus turns out to be a good bioindicator of PCB levels in the coastal areas of Chile due to its wide distribution.
The highest concentrations and the more volatile congeners were found in southern Chile, which could be the result of processes
of long-range transport or illegal discharge occurring in such remote areas. These results confirm previous data from the
International Mussel Watch project ten years ago.
Recommendation and Outlook Future studies are needed to confirm our findings utilizing another environmental matrix such as soil/sediments and air samples. 相似文献
34.
A landscape ecological approach to address scaling problems in conservation management and monitoring 总被引:3,自引:0,他引:3
Management of many African game reserves is today often still an art based on experience and intuition, rather than a science.
Decision-making is based on an informal integration of accumulated individual knowledge and keen field observations. Data
are generally poorly captured and curated. Until fairly recently, denominators of biological parameters (such as the unit
of land or unit of plant production used as measurement) have generally been treated as being homogenous. The patchiness of
landscapes and the issue of ecological scaling were ignored, often because of a lack of appropriate technical tools. The ecological
data available on the 49,000-ha Songimvelo Game Reserve (SGR) result from a number of discrete survey and monitoring projects
undertaken by different researchers, with different objectives, at different spatial and temporal scales. A landscape ecological
approach towards research and monitoring is appropriate for an area of the size and diversity of the SGR. A combination of
a database approach and spatial representation was used to consolidate and integrate data across temporal and spatial scales.
Herbivore spatial and temporal distribution patterns were explored across three spatial scales. An understanding was achieved
of the importance of landscape patchiness in controlling resource availability for herbivores. This insight is important in
guiding management and monitoring of the SGR by placing perceived patch overutilization in its proper landscape context. The
landscape ecological approach bridges the traditional scale-independent view to a more contemporary scale-related understanding
of ecosystem diversity and functioning. 相似文献
35.
In 1991 and 1992 we determined the levels of metals, arsenic, boron, and selenium in the Neosho River drainage in southeastern Kansas, the primary habitat for the threatened Neosho madtom (Noturus placidus). We evaluated concentrations in sediments, mussels (Quadrula pustulosa and Q. metanevra), and fish(Percina phoxocephala, Cyprinus carpio,and Ictiobus bubalus) from three sites on theNeosho River and one site on the Cottonwood River. We also evaluated contaminant concentrations in C. carpio composite samples collected by theKansas Department of Health and Environment (KDHE)at two additional locations on the Neosho River in1990–92. Sediments were contaminated by lead. Concentrations of selenium, boron, and most metalsin mussels were low to normal for biota. Arseniclevels in mussels and fish suggest low-levelcontamination of biota. Aluminum, barium, manganeseand strontium concentrations were much higher inmussels than in fish. Five fish composite sampleshad cadmium concentrations that indicate chronicdeleterious effects on biota. Lead concentrationsin six fish samples were elevated. Mercuryconcentrations in most large fish compositesexceeded concentration for protection of animalsthat might consume them. We believe that reductionsin cadmium, lead, and mercury contamination, inparticular, would benefit aquatic life in theriver. 相似文献
36.
《环境科学学报(英文版)》2023,35(3):332-339
Mono-chlorinated products of cyclic volatile methylsiloxanes (cVMS), i.e., Monochlormet-hylheptamethylcyclotetrasiloxane [D3D(CH2Cl)], monochlormethylnonamethylcyclopenta-siloxane [D4D(CH2Cl)], and monochlormethylundemethylcyclohexasiloxane [D5D(CH2Cl)], were detected in water [<LOQ (Limit of quantitation) -86.3 ng/L, df (detection frequency) = 23%-38%, n=112] and sediment samples [<LOQ-504 ng/g dw (dry weight), df = 33%-38%, n=112] from 16 lakes located in Shengli oilfield of China, and had apparent increasing trends (31%-34% per annum) in sediments during Year 2014-2020. Simulated experiments showed that chloro-cVMS in sediment-water system had approximately 1.7-2.0 times slower elimination rates than parent cVMS. More specifically, compared with those of parent cVMS, volatilization (86-2558 days) and hydrolysis (135-549 days) half-lives of chloro-cVMS were respectively 1.3-2.0 and 1.8-2.1 times longer. In two species of freshwater mussels (n=1050) collected from six lakes, concentrations of chloro-cVMS ranged from 9.8-998 ng/g dw in Anodonta woodiana and 8.4-970 ng/g dw in Corbicula fluminea. Compared with parent cVMS, chloro-cVMS had 1.1-1.5 times larger biota-sediment accumulation factors (2.1-3.0) and 1.1-1.7 times longer half-lives (13-42 days). Their stronger persistence in sediment and bioaccumulation in freshwater mussels suggested that environmental emission, distribution and risks of chloro-cVMS deserve further attention. 相似文献
37.
Municipal wastewaters are major sources of pollution for the aquatic biota. The purpose of this study was to determine the levels of some pharmaceutical products and the immunotoxic potential of a municipal wastewater aeration lagoon for the treatment of the domestic wastewaters of a small town with wastewater inputs from a 400-bed hospital complex. Endemic mussels were collected, caged and placed in the final aeration lagoon and at sites 1 km upstream and 1 km downstream of the effluent outfall in the receiving river for a period of 14 days. The results showed that the final aeration lagoon contained high levels of total coliforms, conductivity and low dissolved oxygen (2.9 mg/L) as well as detectable amounts of trimethoprim, carbamazepine, gemfibrozil, and norfloxacin at concentrations exceeding 50 ng/L. The lagoon effluent was indeed toxic to the mussel specimens, as evidenced by the appearance of mortality after 14 days (10% mortality), decreased mussel weight-to-shell-length ratio and loss of hemocyte viability. The number of adhering hemocytes, phagocytic activity, total nitrite levels and arachidonic cyclooxygenase activity were significantly higher in mussels placed in the final aeration lagoon. A multivariate analysis also revealed that water pH, conductivity, total coliforms and dissolved oxygen were the endpoints most closely linked with phagocytic activity, the amount of adhering hemocytes and loss of hemocyte viability. In conclusion, exposure of mussels to treated aerated lagoon wastewater is deleterious to freshwater mussels where the immune system is compromised. 相似文献
38.
Snejana Moncheva Jacek Namiesnik Resat Apak Patricia Arancibia-Avila Fernando Toledo Seong-Gook Kang 《Chemistry and Ecology》2013,29(1):31-41
The aim of this investigation was to examine biochemical differences in the gastropod Rapana venosa (R. venosa) from polluted (RvP) and nonpolluted (RvN) sites of the Black Sea's Bulgarian coast that may serve as bioindicators of environmental quality. Mussels Mytilus galloprovincialis (MMg) were collected from polluted (MMgP) and nonpolluted (MMgN) sites at the same time for comparison. Bioactive compounds and the antioxidant activity of dry matter (DM) methanol extracts from RvP and RvN were determined. Three-dimensional fluorometry (3D-FL) and Fourier transform infrared (FTIR) analyses were used to evaluate polyphenols and proteins. DM methanol extracts from RvP, and to lesser extent RvN, showed high amounts of total phenolics (23.22±2.9 and 15.60±1.8 mg GAE · g?1 DW) and exhibited high levels of antioxidant activity in some radical scavenging assays (μ MTE · g?1 DW): 56.38±5.2 and 33.79±3.3 by 2,2azino-bis (3-ethyl-benzothiazoline-6-sulfonic acid) diamonium salt (ABTS·+); 54.79±5.6 and 33.7±2.6 by cupric reducing antioxidant capacity (CUPRAC); 62.34±6.8 and 30.31±3.9 by the 1diphenyl-2-picrylhydrazyl method (DPPH). A correlation in the above indices was found between R. venosa and M. galloprovincialis, but all results were relatively higher for M. galloprovincialis than for R. venosa. The obtained indices of R. venosa may serve as a bioindicator of environmental ecological quality. 相似文献
39.
对分布于珠江河口区海域的翡翠贻贝有机氯农药和多氯联苯的含量进行测定 ,结果显示 :HCHs为ND— 1.1ng·g-1,DDTs为 9.5— 191ng·g-1,PCBs为 82 .8— 6 15 .1ng·g-1.尖沙嘴码头 (维多利亚港 )贻贝积累的PCBs浓度最高 ,珠江河口桂山岛和外伶仃岛的贻贝积累的DDTs和PCBs浓度较高 ,而荷包岛 (珠江河口西海区 )的贻贝则检出含量较高的HCHs和DDTs .贻贝选择性积累含 5— 6个氯原子数的PCB异构体 .各采样点贻贝积累的PCBs组成分析表明珠江河口区海域存在两个PCBs污染源 相似文献
40.
Sirpa Herve Harry F. Prest Pertti Heinonen Tarja Hyötyläinen Jaana Koistinen Jaakko Paasivirta 《Environmental science and pollution research international》1995,2(1):24-30
Semipermeable membrane sampling devices (SPMDs) and caged lake mussels (Anodonta piscinalis) were simultaneously deployed at four lake watercourse sites in Central Finland four weeks in August 1992. This study was
part of the regular annual monitoring of the organochlorine compounds (OCC) in pulp-mill recipient watercourses of Finland
with bivalves. Chlorohydrocarbons (CHCs), chlorophenol compounds (PCPs), chloroanisoles (PCAs) and chloroveratroles (PCVs)
were analyzed from lipid extract of mussels and from the synthetic triolein lipid of the SPMDs. Hexane-diethyl ether (9:1,
v/v) dialysis using polyethylene membrane was applied in dean up of the SPMD lipids and, for comparison, to six sets of the
mussel fat. Dialysis recovered CHCs but not PCPs from the mussel fat. CHCs, PCPs, PCAs and PCVs were all recovered in dialysis
of the SPMD lipid. Handling of SPMDs in the transport and deployment operations caused significant OCC contamination for the
blank SPMDs. Similar trends were revealed in the OCC profiles for mussels ans SPMDs. An exception was the lack of PCPs appearing
in SPMDs that did appear in mussels and in a complementary manner the appearance of the PCAs and PCVs in SPMDs. 相似文献