Use of quantitative models to design microbial transport experiments in a sandy aquifer     

Scheibe TD  Chien YJ  Radtke JS 《Ground water》2001,39(2):210-222

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成都近郊农业生态旅游业可持续发展研究   总被引：4，自引：0，他引：4  

杨建翠  殷继成  鄢和琳 《四川地质学报》2001,21(1):60-64

阐述了农业生态旅游业的概念以及成都近郊农业生态旅游业的发展状况及其特点，综合分析了影响成都近郊农业生态旅游可持续发展的一系列问题，并针对这些问题提出了可持续发展对策。  相似文献   

地质雷达在工程,环境管理和地质学方面的应用   总被引：1，自引：0，他引：1  

Mell.  JS 陈王堂 《地震科技情报》1996,(8):10-16

穿透和穿入坚固材料内部的无损技术性能在那些可能需要损害性或破坏性方法进行研究的不同领域有着重要的应用，使用取心或钻探方法探测混凝土，土壤和岩可以提供有关地下特征的详细信息，但是只在距测试孔很近外才有效，地质雷达能够提供有关地下特征的连续的高分辨度剖面，因而可确定不同规模的目标和层位的位置，地质雷达技术在建筑，工程，环境管理以及矿产勘探等各种领域得到应用。  相似文献   

1991年海洋地质和地球物理研究进展     

麦克.  JS 《国土资源信息化》1992,(9):35-36

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Is the invasion of the common reed,Phragmites australis,into tidal marshes of the eastern US an ecological disaster?     

Weis JS  Weis P 《Marine pollution bulletin》2003,46(7):816-820

Studies of effects of the invasive brackish marsh plant Phragmites australis (common reed) on estuarine biota are reviewed. With few exceptions, most field studies indicate that these P. australis-dominated marshes have diverse and abundant benthic biota, and are utilized by nekton, comparable to Spartina alterniflora marshes. However, larval mummichogs, Fundulus heteroclitus, appear to be reduced in P. australis marshes compared with S. alterniflora marshes. Small epifauna living on plant stems also appear to be denser on S. alterniflora than P. australis stems. Other studies indicate that the detritus produced by decaying P. australis litter provides food value comparable to that of S. alterniflora and that its production enters estuarine food webs. Therefore, the general assumption that these marshes are ecologically "useless" is untrue. This information should be considered by marsh managers when making decisions about restoration projects.  相似文献   

Contaminant concentrations in sport fish from San Francisco Bay, 1997     

Davis JA  May MD  Greenfield BK  Fairey R  Roberts C  Ichikawa G  Stoelting MS  Becker JS  Tjeerdema RS 《Marine pollution bulletin》2002,44(10):1117-1129

In 1997, seven sport fish species were sampled from seven popular fishing areas in San Francisco Bay. Mercury exceeded a human health screening value in 44 of 84 (52%) samples. All collected samples of leopard shark and striped bass exceeded the mercury screening value of 0.23 microg/g wet weight. PCBs exceeded the screening value in 51 of 72 (71%) samples. DDT, chlordane, and dieldrin, had lower numbers of samples above screening values: 16 of 72 (22%) for DDT, 11 of 72 (15%) for chlordanes, and 27 of 72 (37%) for dieldrin. Concentrations of PCBs and other trace organics were highest in white croaker and shiner surfperch, the two species with the highest fat content in their muscle tissue. Fish from one location, Oakland Harbor, had significantly elevated wet weight concentrations of mercury, PCBs, DDTs, and chlordanes compared to other locations. Removal of skin from white croaker fillets reduced lipid concentrations by 27-49% and concentrations of trace organics by 33-40%.  相似文献   

Mercury uptake by the estuarine species Palaemonetes pugio and Fundulus heteroclitus compared with their parasites,Probopyrus pandalicola and Eustrongylides sp     

Bergey L  Weis JS  Weis P 《Marine pollution bulletin》2002,44(10):1046-1050

When exposed to methylmercury in the laboratory, grass shrimp, Palaemonetes pugio, parasitized by the isopod Probopyrus pandalicola, accumulated lower concentrations of mercury than their unparasitized counterparts. The parasitic isopod accumulated far less mercury than the grass shrimp. When exposed to mercury in a contaminated field site, mummichogs, Fundulus heteroclitus, parasitized with the nematode Eustrongylides, similarly accumulated lower concentrations of mercury than unparasitized fish, and the parasite similarly accumulated less than the host. The lower uptake by the parasites compared to their hosts is counter to the general view of biomagnification of methylmercury, since parasites are a trophic level above their hosts. The mechanism whereby parasitized animals accumulate less toxicant than unparasitized ones is unknown, but may be partially due to lower metabolic rate.  相似文献   

cDNA cloning and expression of a cytochrome P450 1A (CYP1A) gene from the hermaphroditic fish Rivulus marmoratus     

Lee YM  Williams TD  Jung SO  Lee JS 《Marine pollution bulletin》2005,51(8-12):769-775

We previously described the genomic structure of the cytochrome P450 1A (CYP1A) gene from the hermaphroditic fish Rivulus marmoratus [Kim, I.-C., Kim, Y.J., Yoon, Y.-D, Kawamura, S., Lee, Y.-S., Lee, J.-S., 2004a. Cloning of cytochrome P450 1A (CYP1A) genes from the hermaphroditic fish Rivulus marmoratus and the Japanese medaka Oryzias latipes. Mar. Environ. Res. 58, 125–129]. To further characterize R. marmoratus CYP1A, we cloned the cDNA sequence of a CYP1A gene from this species and also expressed its recombinant protein in an E. coli system. We exposed R. marmoratus to 4-nonylphenol, and found a small induction of CYP1A mRNA in the treated animals. In this paper, we discuss the characteristics of R. marmoratus CYP1A gene as well as its potential use in a biomonitoring assay.  相似文献   

Constraints on spatial variability in soft-sediment communities affected by contamination from an Antarctic waste disposal site   总被引：1，自引：0，他引：1  

Stark JS  Snape I  Riddle MJ  Stark SC 《Marine pollution bulletin》2005,50(3):276-290

A small-scale (<500 m length) transect-based survey was conducted in December 1998 to examine the spatial distribution of soft-sediment communities and of concentrations of heavy metals and hydrocarbons in sediments in Brown Bay, adjacent to an abandoned waste dump, at Casey Station, Antarctica. Samples were taken along three transects at increasing distances (nine stations) from the shore-line waste dump. A gradient of contamination was detected, but concentrations of contaminants were very variable with "hotspots" or high levels of contaminants at some stations. Multivariate analysis revealed that the distribution of soft-sediment communities was distinctly different between the inner, middle and outer stations. Abundances of most taxa were very variable with few patterns apparent, but some fauna displayed an abundance gradient from the inner to the outer part of the bay. Many taxa had maximum abundances at outer stations and minimum at inner stations. Multivariate correlations between environmental variables and soft-sediment communities indicated that combinations of some metals (Cd, Cu, Sn, Pb) and grain size (mainly finer fractions, fine sands and coarse silts) were the variables that best "matched" the community patterns within Brown Bay. This study indicated that there were significant correlations between the presence of contaminants and the distribution and composition of soft-sediment communities over very small spatial scales.  相似文献   

Predicting copper toxicity in estuarine and marine waters using the Biotic Ligand Model   总被引：6，自引：0，他引：6  

Arnold WR  Santore RC  Cotsifas JS 《Marine pollution bulletin》2005,50(12):1634-1640

The Biotic Ligand Model (BLM) has proven efficient in predicting the toxicity of a variety of metals to freshwater organisms. Consequently, the US EPA has proposed its use for calculating freshwater copper criteria. This study evaluates the BLM for use in estuarine and marine waters. Studies were conducted using the bivalve, Mytilus sp. and 48-h embryo-larval development chronic estimator test methods. These are the most sensitive taxa and test in the US EPA saltwater copper criteria database. Samples from five locations around the USA were tested. There is a strong relationship between measured and BLM predicted copper EC50s (log transformed data, r² = 0.76, p < 0.001, n = 44). The BLM predicted within a factor ±2 of measured EC50s in 41 of 44 cases. However, the BLM tends to predict lower EC50s when measured EC50s are approximately 10 μg Cu/L. This may be due to limitations of the metal-dissolved organic matter interaction model.  相似文献