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51.
We evaluated performance of species distribution models for predictive mapping, and how models can be used to integrate human pressures into ecological and economic assessments. A selection of 77 biological variables (species, groups of species, and measures of biodiversity) across the Baltic Sea were modeled. Differences among methods, areas, predictor, and response variables were evaluated. Several methods successfully predicted abundance and occurrence of vegetation, invertebrates, fish, and functional aspects of biodiversity. Depth and substrate were among the most important predictors. Models incorporating water clarity were used to predict increasing cover of the brown alga bladderwrack Fucus vesiculosus and increasing reproduction area of perch Perca fluviatilis, but decreasing reproduction areas for pikeperch Sander lucioperca following successful implementation of the Baltic Sea Action Plan. Despite variability in estimated non-market benefits among countries, such changes were highly valued by citizens in the three Baltic countries investigated. We conclude that predictive models are powerful and useful tools for science-based management of the Baltic Sea.  相似文献   
52.
煤基腐殖酸对外源砷胁迫下玉米生长及生理性状的影响   总被引:1,自引:0,他引:1  
为了筛选用于砷污染土壤治理的煤基腐殖酸,采用盆栽实验研究了施用不同种类和浓度的煤基腐殖酸及EDTA对外源砷胁迫下玉米株高、株鲜重、株干重、根干重、砷积累量、叶片抗氧化酶(POD,SOD和CAT)活性和脯氨酸含量的影响。结果表明,11种供试煤基腐殖酸均促进了玉米生长,提高了叶片POD、SOD和CAT活性。其中6和10号腐殖酸可降低土壤砷活性和显著抑制玉米吸收和积累砷,而8和9号腐殖酸增加了土壤活性砷和显著促进了玉米对砷的吸收和累积,且不同程度地强于EDTA。除8和9号外,其余腐殖酸均可明显降低玉米叶片脯氨酸的含量。EDTA可显著促进玉米吸收和积累砷,且加剧了砷对玉米的危害。因此,8和9号供试煤基腐殖酸可以替代EDTA活化土壤砷,与植物配合以提高砷污染土壤的植物修复速度和效果,而6和10号供试煤基腐殖酸则可用于土壤砷钝化剂,以保证作物产品的安全。  相似文献   
53.
针对装置平台抗震能力的现状 ,研究了江苏油田真武液化气装置平台的抗震加固。即在原设备不拆除的情况下 ,提出了对框架梁、柱采用钢构套进行加固 ,并对框架柱采用钢构斜支撑加翼补强的加固设计方案和具体的加固措施。经加固后的装置平台 ,整体抗震性能得到提高 ,从而消除了隐患 ,增强了日常工作的可靠性。  相似文献   
54.
通过比较2×300 MW燃煤发电机组3种电除尘改造思路的可行性,综合考虑空间布置、运行的安全可靠性,确定采用袋式除尘技术加以改造。电除尘器改造为袋式除尘器的方案,包括主要设计参数选择、系统设计、改造工程费用与预期的环境效益。改造后,袋式除尘器运行安全、可靠,完全满足国家烟尘排放标准。  相似文献   
55.
Zhan  Junyi  Yang  Qin  Lin  Zhiyi  Zheng  Tianrun  Wang  Maojia  Sun  Wenjun  Bu  Tongliang  Tang  Zizhong  Li  Chenglei  Han  Xueyi  Zhao  Haixia  Wu  Qi  Shan  Zhi  Chen  Hui 《Environmental science and pollution research international》2021,28(11):13275-13287
Environmental Science and Pollution Research - Conyza blinii (C. blinii) is a traditional Chinese medicinal plant mainly grown in Sichuan, China. C. blinii is suitable for studying the mechanism of...  相似文献   
56.
Environmental Science and Pollution Research - The goal of this study was to identify antibiotics with potential risk in river water of the megacity Beijing, China. This was accomplished by using a...  相似文献   
57.
DEHP (di(2-ethylhexyl) phthalate) is an endocrine disruptor commonly found in plastic products that has been associated with reproduction alterations, but the effect of DEHP on toxicity is still widely unknown. Using DEHP concentrations of 10, 1, and 0.1 mg/L, we showed that DEHP reduced the reproductive capacity of Caenorhabditis elegans after 72 hr. of exposure. DEHP exposure reduced the reproductive capacity in terms of decreased brood sizes, egg hatchability (0.1, 1 and 10 mg/L), and egg-laying rate (1 and 10 mg/L), and increased numbers of fertilized eggs in the uterus (1 and 10 mg/L). DEHP also caused damage to gonad development. DEHP decreased the total number of germline cells, and decreased the relative area of the gonad arm of all exposure groups, with worms in the 1 mg/L DEHP exposure group having the minimum gonad arm area. Additionally, DEHP caused a significant concentration‐dependent increase in the expression of unc-86. Autophagy and ROS contributed to the enhancement of DEHP toxicity in reducing reproductive capacity, and glutathione peroxidase and superoxide dismutase were activated as the antioxidant defense in this study. Hence, we found that DEHP has a dual effect on nematodes. Higher concentration (10 mg/L) DEHP can inhibit the expression of autophagy genes (atg-18, atg-7, bec-1, lgg-1 and unc-51), and lower concentrations (0.1 and 1 mg/L) can promote the expression of autophagy genes. Our data highlight the potential environmental risk of DEHP in inducing reproductive toxicity toward the gonad development and reproductive capacity of environmental organisms.  相似文献   
58.
热振森林大型土壤动物群落特征及其影响因素   总被引:1,自引:0,他引:1  
为了解西藏拉萨市林周县热振国家森林公园不同海拔大型土壤动物群落的空间分布特征及其与环境因子的关系,于2021年7月(夏季)根据其地理特征设置了三个不同海拔共9个样地.采用手捡法对大型土壤动物进行收集,并将其保存在75%酒精的收集管中,同时测定相应的环境因子.共捕获大型土壤动物1427个,经形态学鉴定隶属于2门5纲15目21科,其中优势类群为姬马陆科(Julidae)和蚁科(Formicidae),占总捕获量的66.0%.常见类群共10类,占总捕获量的31.3%;稀有类群占总捕获量的2.7%.热振国家森林公园大型土壤动物的类群、Shannon多样性指数、均匀度指数和优势度指数在三个不同海拔之间无显著性差异(P>0.05).大型土壤动物群落Jaccard相似性系数位于0.15~0.77.Pearson相关性结果显示,大型土壤动物个体数与海拔呈极显著负相关(P<0.01),与土壤温度和pH呈显著正相关(P<0.05);冗余分析显示,排序轴1和轴2共同解释了的类群组成变化的55.0%,全磷(TP)和有效磷(AP)为显著性解释变量,对大型土壤动物群落的解释率分别为29.6%和18.5%,是影响大型土壤动物群落的主要环境因子.  相似文献   
59.
The content of phthalate esters (PAEs) was investigated in urban soil samples ( = 127, 0-20 cm) collected from a business area (BU), classical garden (CL), culture and educational area (CU), large public green space (LA), residential area (RE), and roadside area (RO) in Beijing. The sum of all PAE contents ranged from 1.9 to 3141.7 ng/g, with an average of 1139.6 ± 727.6 ng/g. Di-n-butyl phthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP) were the major contaminants in the soil samples. The content of DEHP and DBP in the urban soil of Beijing showed decreasing trends from the center of the city to the suburbs, which was probably because the center of the city has a longer history. In addition, higher DBP content also occurred in the south of the city, which was caused by the existence of several factories that produce commodity chemical and building materials in these areas. Because of its greater age, less disturbance from human activity, and high levels of total organic carbon and black carbon in CL, PAE content in CL was the highest among the six types of land use, followed by RE, CU, BU, LA, and RO. Although in 82.6% of the soil samples, DBP content exceeded the recommended allowable soil content in New York, USA, health risk assessment with CalTOX and Monte Carlo analysis showed that the total cancer risk values of PAEs were lower than the acceptable cancer risk value (10(-4)) and that the risk mainly came from dermal uptake and inhalation exposure pathways.  相似文献   
60.
尕斯库勒联合站采出水治理是青海油田采油一厂环境保护的一项重要工作。为了对油田采出水进行综合治理,尕斯库勒联合站先后对原有的采出水处理系统进行了四次技术改造,通过多年的实践与探索,找到了满足青海油田采出水处理需求较为成熟的采出水处理技术。  相似文献   
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