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521.
Adaptive maritime spatial planning (MSP) uses monitoring and evaluation of the effectiveness of spatial and temporal management measures to promote understanding and improve planning and decision-making. An adaptive approach to MSP involves exploring alternative ways to meet management objectives, predicting the outcomes of alternative management measures, implementing one or more of these alternative management measures, monitoring to learn about the effects of management measures, and then using the results to update knowledge and adjust management actions. A monitoring and evaluation plan should be designed to be both cost effective and comprehensive. The process of setting and assessing performance metrics requires that the ecological and socio-economic objectives of the spatial management plan must be clearly stated up front for management actions to reflect those objectives accurately. To evaluate the effectiveness of a MSP plan, a range of ecological, socio-economic and institutional indicators need to be developed and monitored.  相似文献   
522.
In this paper, we explore a range of concerns that arise in measuring short-term effects of ozone on health. In particular, we tackle the problem of measuring exposure using alternative daily measures of ozone derived from hourly concentrations. We adopt the exposure paradigm of Chiogna and Bellini (Environmetrics 13:55–69, 2002) extending it to ozone concentrations, and we compare its performances with respect to traditional exposure measures by exploiting model selection. To investigate the stability of model selection, we then apply the idea of bootstrapping the modelling process.  相似文献   
523.
Salinity levels vary spatially in coastal areas, depending on proximity to freshwater sources, and may also be slowly decreasing as a result of anthropogenic climatic changes. The impact of salinity on host–parasite interactions is potentially a key regulator of transmission processes in intertidal areas, where trematodes are extremely common parasites of invertebrates and vertebrates. We investigated experimentally the effects of long-term exposure to decreased salinity levels on output of infective stages (cercariae) and their transmission success in the trematode Philophthalmus sp. This parasite uses the snail Zeacumantus subcarinatus as intermediate host, in which it asexually produces cercariae. After leaving the snail, cercariae encyst externally on hard substrates to await accidental ingestion by shorebirds, which serve as definitive hosts. We found that at reduced salinities (25 or 30 psu), the cercarial output of the parasite was lower, the time taken by cercariae to encyst was longer, fewer cercariae successfully encysted and encysted parasites had lower long-term survival than at normal seawater salinity (35 psu). The strong effect of salinity on the replication and transmission of this parasite suggests that there may be sources and sinks of transmission to birds along coastal areas, depending on local salinity conditions. Also, unless it evolves to adapt to changing conditions, the predicted reduction in salinity as a consequence of climate change may have negative impact on the parasite’s abundance.  相似文献   
524.
Loss of zooxanthellae (dinoflagellate Symbiodinium) from corals will sometimes lead to mass mortality of corals. To detect and quantify Symbiodinium released from corals, we developed a zooxanthellae “trap” and a quantitative PCR (qPCR) system with Symbiodinium clades A–F-specific primer sets. The trap was attached to a branch or the surface of several wild stony corals, and the water samples within the traps, including released Symbiodinium, were subjected to qPCR. All tested corals released clade C Symbiodinium at estimates of ~5,900 cells h−1 cm−2 of coral surface. Although all tested Pocillopora eydouxi harboured both clades C and D, some of these colonies released only clade C or released a lesser amount of clade D than that in the tissues. Our Symbiodinium quantification system revealed that wild hermatypic corals constantly release Symbiodinium to the environment. Our result suggests that some corals may discharge certain clades of Symbiodinium alternatively.  相似文献   
525.
526.
石油降解菌的分离鉴定及4株芽胞杆菌种间效应   总被引:1,自引:0,他引:1  
王佳楠  石妍云  郑力燕  王喆  蔡章  刘杰 《环境科学》2015,36(6):2245-2251
通过富集培养和分离纯化的方法,从天津大港油田石油污染土壤和渤海海上钻井平台洗油污水中分离出6株石油降解细菌,生理生化试验及16S r DNA序列分析鉴定表明,它们分别属于Bacillus芽胞杆菌属(S1、S2、S3、S4)、Pseudomonas假单胞菌属(W1)和Ochrobactrum苍白杆菌属(W2),其中,S3具有最高的烷烃(41.3%)和芳烃(30.9%)降解率,从石油污染场地中筛选出的内源微生物对本油田石油的降解效果优于外源物种.对4株芽胞杆菌属菌株构建微生物组进行石油降解实验,结果表明,由S1和S4构成的微生物组F3具有最高的烷烃(50.5%)和芳烃(54.0%)降解率,比单菌降解率分别提高了69.9%和156.1%,同时比最优降解单菌S3的降解率分别高出22.1%和74.6%,而由S2和S3构成的微生物组F4对烷烃和芳烃的降解率最低,分别为18.5%和18.9%,比单菌降解率降低了55.3%和39.0%,实验表明同菌属微生物种间对石油的降解同时存在协同促进和拮抗抑制作用,芽胞杆菌属内亲缘性近的菌株之间对石油降解主要表现为促进作用.  相似文献   
527.
Environmental Science and Pollution Research - A large amount of biochar-derived dissolved organic matter (BDOM) will be released into the environment with biochars application into repairing...  相似文献   
528.
Environmental Science and Pollution Research - Groundwater pollution seriously threatens water resource safety due to high-intensity land use throughout the world. However, the relationship between...  相似文献   
529.
Environmental Science and Pollution Research - The massive use of silver nanoparticles (AgNPs) is potentially harmful to exposed humans. Although previous studies have found that AgNPs can induce...  相似文献   
530.
Environmental Science and Pollution Research - The rapid economic development in China places a large demand for energy, and as a result, thermal power plants in China are producing an enormous...  相似文献   
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