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781.
The objective of this research is to develop a desirable type III environmental declaration format for the industrial consumer.
A total of five different scenarios were chosen for the presentation of life-cycle assessment results in a format that meets
the requirements of a type III environmental declaration. Life-cycle assessment of an electronic component was performed for
this purpose. Environmentally significant impact categories and input/output items of a product system derived from the life-cycle
assessment are presented in this format. Presenting these information concisely in a standardized format would accelerate
the communication of environmental aspects of materials and components in a product supply chain. Thus the type III environmental
declaration can be a useful instrument for the manufacturing of an ecoproduct. 相似文献
782.
Jen‐Yang Lin Shaw L. Yu Tsu‐Chuan Lee 《Journal of the American Water Resources Association》2000,36(5):989-1001
ABSTRACT: For many years, a commonly used strategy for source water protection in Taiwan has been setting up arbitrary, fixed‐width buffer zones near sensitive waters, such as water‐supply reservoirs, and prohibiting any development in their watersheds. However, such regulations are now often viewed as infringing by the government on landowners' property rights, a situation that has led to citizen protests. This paper describes a proposed strategy that is water‐quality based and uses a quantitative zoning approach. A reservoir's watershed is divided into several zones beginning from the normal water line to the divide. Different levels of best management practices (BMPs) are required for controlling runoff pollution in different zones. The layout of the management zones is based on a number of factors such as reservoir classification, water quality conditions, and physical characteristics of the watershed. The goal of promoting such an approach is to try to balance the needs of watershed development and water quality protection. A case study using the Tapu Reservoir Watershed in Northern Taiwan as an example for illustrating the proposed zoning approach is presented. 相似文献
783.
Timothy O. Randhir John G. Lee 《Journal of the American Water Resources Association》2000,36(3):595-608
ABSTRACT: Enforceable standards play a crucial role in the design and implementation of most water quality policies. The impacts of these standards on farm income and nonpoint source (NPS) pollution can provide valuable information to develop economic policies that can improve water quality with minimal loss in income and minimal risk. This study uses an integration of nonlinear programming and a simulation model to assess the impacts of enforceable standards at technology and farm boundary levels. The results indicate that the type of pollutant regulated, enforcement type, and the level of standard had a significant impact on farm income and water quality. Choice of farm boundary standards over technology standards is dependent on the impact of the policy on other NPS pollutants, in addition to the reduction of nitrate and phosphorus pollutants. Enforcing farm boundary standards on nitrates had desirable effects on subsurface and percolate nitrogen and variance in income. Technology standards were uncertain in their effects because of the restriction on the choice of technologies available to farmers. A comparative policy analysis considering incentives, multiple impacts, transaction costs of implementation, and regional consideration is important to an effective policy design. 相似文献
784.
C M Chen M C Liu M L Shih S C Yu C C Yeh S T Lee T Y Yang S J Hung 《Chemosphere》2001,45(4-5):581-588
Bleached kraft pulp and paper mill effluents (BKMEs) are known to have adverse effects on aquatic organisms. One of the effects of BKMEs is its ability to induce cytochrome P4501A activity in exposed fish. 7-Ethoxyresorufin O-deethylase (EROD) activity is the most common biomarker used to measure the mixed-function monooxygenase activity. In this study, Tilapia were exposed to BKMEs using different exposure systems and their hepatic EROD activity, as well as liver/somatic index (LSI), were determined. In the Phase I study, Tilapia treated with betaNF and a whole (100%) BKME using a static, non-renewal system exhibited statistically significant EROD induction, but LSI values were not altered. In the Phase II study, fish were either caged in the mill's fishpond with the whole effluent passing through or cultured in tanks receiving 100% of the BKME continuously using a flow-through system in the laboratory. Their EROD activities were then compared with the non-exposed fish (control). The EROD activities in both groups of fish were elevated significantly with the greatest induction being observed in the field-exposed group. The LSI values in all of the field-exposed fish were significantly greater than the control Tilapia. The EROD assay was sensitive in detecting biological changes in fish exposed to the BKME. Further studies are warranted to better understand the impacts of BKMEs on aquatic organisms in Taiwan. 相似文献
785.
Longevity can buffer plant and animal populations against changing climatic variability 总被引:3,自引:0,他引:3
Morris WF Pfister CA Tuljapurkar S Haridas CV Boggs CL Boyce MS Bruna EM Church DR Coulson T Doak DF Forsyth S Gaillard JM Horvitz CC Kalisz S Kendall BE Knight TM Lee CT Menges ES 《Ecology》2008,89(1):19-25
Both means and year-to-year variances of climate variables such as temperature and precipitation are predicted to change. However, the potential impact of changing climatic variability on the fate of populations has been largely unexamined. We analyzed multiyear demographic data for 36 plant and animal species with a broad range of life histories and types of environment to ask how sensitive their long-term stochastic population growth rates are likely to be to changes in the means and standard deviations of vital rates (survival, reproduction, growth) in response to changing climate. We quantified responsiveness using elasticities of the long-term population growth rate predicted by stochastic projection matrix models. Short-lived species (insects and annual plants and algae) are predicted to be more strongly (and negatively) affected by increasing vital rate variability relative to longer-lived species (perennial plants, birds, ungulates). Taxonomic affiliation has little power to explain sensitivity to increasing variability once longevity has been taken into account. Our results highlight the potential vulnerability of short-lived species to an increasingly variable climate, but also suggest that problems associated with short-lived undesirable species (agricultural pests, disease vectors, invasive weedy plants) may be exacerbated in regions where climate variability decreases. 相似文献
786.
Relative and interactive effects of plant and grazer richness in a benthic marine community 总被引:2,自引:0,他引:2
The interactive effects of changing biodiversity of consumers and their prey are poorly understood but are likely to be important under realistic scenarios of biodiversity loss and gain. We performed two factorial manipulations of macroalgal group (greens, reds, and browns) and herbivore species (amphipods, sea urchin, and fish) composition and richness in outdoor mesocosms simulating a subtidal, hard-substratum estuarine community in North Carolina, U.S.A. In the experiment where grazer richness treatments were substitutive, there were no significant effects of algal or herbivore richness on final algal biomass. However, in the experiment in which grazer treatments were additive (i.e., species-specific densities were held constant across richness treatments), we found strong independent and interactive effects of algal and herbivore richness. Herbivore polycultures reduced algal biomass to a greater degree than the sum of the three herbivore monocultures, indicating that the measured grazer richness effects were not due solely to increased herbivore density in the polycultures. Taking grazer density into account also revealed that increasing algal richness dampened grazer richness effects. Additionally, the effect of algal richness on algal biomass accumulation was far stronger when herbivores were absent, suggesting that grazers can utilize the increased productivity and mask the positive effects of plant biodiversity on primary production. Our results highlight the complex independent and interactive effects of biodiversity between adjacent trophic levels and emphasize the importance of performing biodiversity-ecosystem functioning experiments in a realistic multi-trophic context. 相似文献
787.
Shumei Jiang Xiang Li Long Zhang Wei Sun Shikun Dai Lianwu Xie Yonghong Liu Kyung Jin Lee 《Marine Biology》2008,153(5):945-952
The study describes the diversity of actinobacteria isolated from the marine sponge Iotrochota sp. collected in the South China Sea. Species and natural product diversity of isolates were analyzed, including screening
for genes encoding polyketide synthases (PKS) and nonribosomal peptide synthetase (NRPS), and 16S rRNA gene restriction fragment
length polymorphism (RFLP). PKS and NRPS sequences were detected in more than half of the isolates and the different “PKS-I–PKS-II–NRPS”
combinations in different isolates belonging to the same species indicated a potential natural product diversity and divergent
genetic evolution. The phylogenetic analysis based on 16S rRNA gene sequencing showed that the isolates belonged to genera
Streptomyces, Cellulosimicrobium, and Nocardiopsis. The majority of the strains tested belonged to the genus Streptomyces and one of them may be a new species. To our knowledge, this is the first report of a bacterium classified as Cellulosimicrobium sp. isolated from a marine sponge.
Key Laboratory of Marine Bio-recourses Sustainable Utilization (LMB-CAS), Guangdong Key Laboratory of Marine Materia Medica
(LMMM-GD), South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, People’s Republic of China. 相似文献
788.
Bhattarai HD Paudel B Park NS Lee KS Shin HW 《Journal of environmental biology / Academy of Environmental Biology, India》2007,28(4):857-863
Environmental impacts caused by tin and copper based commercial antifouling (AF) paints were proved to be detrimental to aquatic ecosystems. Therefore, a search of environmental friendly AF compounds to be used in marine paint to protect the surface of maritime developmental structures from the unwanted biofouling is a burning issue of the present time. Commercially available eight organic chemicals--allyl isothiocyanate, beta-myrecene, cis-3-hexenyl acetate, citral, ethyl heptanoate, eugenol, methyl caproate, and octyl alcohol were evaluated forAF activities using both laboratory and field assays. The test chemicals were found to repel the target motile marine bacteria--Alteromonas marina, Bacillus atrophaeus, Roseobactergallaeciensis and Shewanella oneidensis and motile spores of the green alga, Ulva pertusa. The bacterial and Ulva spore repulsion activities of the test chemicals were measured by chemotaxis and agar diffusion methods respectively interestingly these test chemicals were less toxic to the test fouling species. The toxicity of the test chemicals was measured by using antibiotic assay disks against the bacteria and motility test against Ulva spores. Moreover, in field assay, all test chemicals showed a perfect performance ofAF activity showing no fouling during the experimental period of one year Such results and commercial as well as technical feasibility of the test chemicals firmly showed the possibility of using as alternatives of the existing toxic AF agents. 相似文献
789.
Batch scale reactions were conducted to evaluate the efficacy of modified low-grade kaolin for the treatment of petroleum
contaminants. Low-grade kaolin, which has been unvalued as material in the mining process because of its low quality for commercial
products, was modified with HDTMA (hexadecyl-trimethylammonium), and its efficiency was compared with that of HDTMA-modified
bentonite, which is used as a secondary containment barrier for underground storage tanks. The sorption capacity and hydraulic
conductivity of both the HDTMA-modified bentonite and low-grade kaolin were investigated and showed distribution coefficients
in the sorption of benzene, toluene, ethylbenzene and xylene ranging between 45.7 and 583.7 and 57.0 and 525.1, respectively.
The hydraulic conductivities were 2.53 × 10−8 and 5.62 × 10−8 cm/s for the HDTMA-modified bentonite and low-grade kaolin, respectively. These results suggest that HDTMA-modified low-grade
kaolin could be used as a hydraulic barrier against advection migration of petroleum contaminants. Simulation of the one-dimensional
transport of benzene through a liner made of either one of the compounds was also performed. These results also showed that
HDTMA-modified kaolin more effectively retards the transport of benzene. 相似文献
790.
Bioleaching from soil artificially contaminated with analogues of radionuclides, Co and Sr, was carried out using a Fe-oxidizing
bacterium, Acidithiobacillus ferrooxidans. Due to bacterial metabolism, the pH and dissolved Fe3+ concentration in a biotic slurry decreased and increased respectively, over time, but the concentrations of Co and Sr extracted
from the soil showed no significant enhancement compared with those under abiotic control. In both cases, Co and Sr were leached
from the soil during the initial period of the experiment, due to the initially low solution pH of 2.0, and the dissolved
concentrations remained almost constant for the duration of the experiment (300 h). Since oxidation of Fe2+ by A. ferrooxidans led to the production of Fe precipitates and colloidal suspensions, the Co and Sr extracted into solution were most likely
re-adsorbed onto the Fe solids. Also, A. ferrooxidans, without an external supply of Fe2+, extracted almost equal or greater amounts of Co and Sr from the soil than when Fe2+ was supplied. Under the same leaching conditions, the extent of Sr removal was much lower than that of Co. On the contrary
to the high efficiency of microbial metal leaching in biohydrometallurgy for low-graded sulfide ores, which has been widely
documented, conventional bioleaching techniques with A. ferrooxidans supplied with enough Fe2+ showed low efficiency for the removal of radionuclides loosely bound onto soil particle surfaces. 相似文献