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61.
Á. Pereira A. Carballo-Penela A. Guerra X. Vence 《Journal of Environmental Planning and Management》2018,61(2):348-369
The servicising approach in vineyard protection is considered a valid alternative to achieve decoupling between the economic and environmental performance of viticulture. In this paper, a policy package is designed to promote the uptake of a servicised model of vineyard protection in an area of smallholding viticulture. In doing so, a specific methodology based on a step by step protocol has been followed that aims to come up with a package that is effective, implementable and socially as well as politically acceptable. The paper concludes on the importance of combining several policy instruments in a policy package to realise the political objective. The proposed viable policy package includes incentives that support the companies’ shift towards offering crop protection solutions, further development of IPM solutions and instruments that encourage farmers to reduce the use of pesticides and collectively hire crop protection services. 相似文献
62.
The Mekong River Delta in Vietnam plays a crucial role for the region in terms of food security and socioeconomic development; however, it is one of the most low-lying and densely populated areas in the world. It is vulnerable to seawater incursion, flood risk, and shoreline change, exacerbated as a consequence of sea-level rise (SLR) related to climate change. This study examined the Kien Giang coast in the western part of the delta, comprising seven coastal districts (namely Ha Tien, Kien Luong, Hon Dat, Rach Gia, Chau Thanh, An Bien, and An Minh), the economy of which is important in terms of agriculture and aquaculture. The analytical hierarchical process (AHP) method of multi-criteria decision making was integrated directly into geographic information systems (GIS) to derive a composite vulnerability index that indicated areas most likely to be vulnerable to SLR. The hierarchical structure comprised three key components: exposure (E), sensitivity (S), and adaptive capacity (A), at level 1. At the next level, 8 sub-components were mapped: seawater incursion, flood risk, shoreline change, population characteristics, land use/land cover, and socioeconomic, infrastructure, and technological capability, beyond which a further 22 variables (level 3) and 24 sub-variables (level 4) related to vulnerability were also mapped. Variables were assigned weights for incorporation into AHP pairwise comparisons after discussion with stakeholders. Maps were generated to visualise areas where the relative vulnerability was very low, low, moderate, high, and very high. Societal data were generally only available at district level; however, several regional patterns emerged. Relatively high exposure to flooding and inundation, salinity, and moderate loss of mangroves occurred along the coastal fringe of each district. This western section of the delta, which is low-lying and remote from the distributaries that carry sediment to the coast, appears to be particularly vulnerable. The most sensitive areas tended to be ethnic households engaged in rice cultivation and with moderate population density. The least adaptable areas consisted of high numbers of poor households, with low income, and moderate densities of transport, irrigation and drainage systems. Most coastal districts were determined to be moderately to relatively highly vulnerable, with scattered hotspots along the coast. 相似文献
63.
64.
Environmentally Friendly Polyurethane Composites: Preparation, Characterization and Mechanical Properties 总被引:1,自引:0,他引:1
J. L. Zhang D. M. Wu D. Y. Yang F. X. Qiu 《Journal of Polymers and the Environment》2010,18(2):128-134
The waterborne polyurethane (PU) prepolymer was prepared based on isophorone diisocyanate (IPDI), polyester polyol (N220), dimethylol propionic acid (DMPA) and hydroxyethyl methyl acrylate (HEMA). The modified waterborne polyurethane–acrylate (PUA) emulsions were obtained with different proportions of acrylate (butyl acrylate and methyl methacrylate) and initiating agent by in situ dispersion technique. The structures and thermal properties of prepared PU and PUA were analyzed and characterized with FT-IR, UV–Vis spectroscopy and DSC. The PUA hybrid samples had lower glass transition temperature of hard segment and higher decomposition temperatures than PU sample. Performances of the emulsion and film were studied by means of apparent viscidity, particle size and polydispersity, surface tension and mechanical properties. The results indicated that the particle sizes of the PUA dispersions were larger than those of the pure PU and the solvent resistance, mechanical properties of PUA films was improved compare with the unmodified polyurethane film. The film had the biggest hardness and the least water absorption when the BA/MMA mass ratio 5:5 modified PU. The obtained PUA have great potential application such as coatings, leather finishing, adhesives, sealants, plastic coatings and wood finishes. 相似文献
65.
为进一步探究夏季太湖CDOM(有色溶解性有机质)光学特性在空间分布上的差异性与其来源的关系,对其紫外-可见吸收及三维荧光光谱特性进行了分析研究,在此基础上进一步分析了CDOM吸尘系数及其荧光组分(C1、C2、C3、C4)强度和各水质参数间的相关性.结合主成分分析法探讨了CDOM的来源以及与各参数指标[ρ(DOC)除外]之间的来源关系.结果表明:CDOM吸收系数α(355)、S值(光谱斜率)变化范围分别为3.27~8.27 m-1和0.011~0.021 nm-1;太湖西部、北部及南部湖区CDOM丰度较大,S值较低,受陆源输入的影响较为明显.CDOM的三维荧光光谱揭示其中含有两种类蛋白质组分C1和C2以及类腐殖质组分C3和C4,并且以类蛋白质组分为主.此外,大部分采样点的荧光指数(FI)为1.70~2.01,自生源指数(BIX)大于1,腐殖化指数(HIX)小于0.6,r(T/C)(荧光峰T与荧光峰C荧光强度比值)小于2,表明夏季太湖CDOM内源特性相对强烈.研究显示,除ρ(DOC)外,CDOM与其他水质参数在第一主成分上(贡献率为90.8%)均存在显著相关关系,说明各水质参数的来源存在相似性,并且受生物自生源影响更为显著. 相似文献
66.
为评价三峡库区主要水域典型抗生素的污染状况和生态风险,利用固相萃取-高效液相色谱-串联三重四极杆质谱联用法(SPE-HPLC-MS/MS),分析三峡库区长江干流和6条支流表层水体中6类28种抗生素的质量浓度,根据欧盟环境风险评价方法计算RQS(风险商值)及RQsum(联合风险商值),并按照Hernando等提出评级方法评价研究区域的生态风险等级.结果表明:三峡库区7条河流共检出4类10种抗生素,质量浓度范围为0.6~218.0 ng/L,其中除OFX(氧氟沙星)和CAP(氯霉素)外,其余8种[SDI(磺胺嘧啶)、SMX(磺胺甲 唑)、SMZ(磺胺二甲嘧啶)、ERM(红霉素)、ROM(罗红霉素)、TYL(泰乐菌素)、FF(氟苯尼考)、LIN(林可霉素)]均为畜禽药品,并且FF、LIN在我国畜禽药品中使用量排名居前五位.7条河流抗生素RQsum由高到低依次为濑溪河>琼江>綦江>碧溪河>嘉陵江>长江>乌江,其中,濑溪河RQsum高达5.532,SMX、ERM和OFX均为高风险,说明其对濑溪河水体中相应的水生生物表现出较高的毒性风险;琼江、綦江、碧溪河和嘉陵江的RQsum均处于1~2之间,表现出较高生态风险,但4条河流检出抗生素的单个RQS均小于1,处于低风险;长江的RQsum为0.605,检出抗生素中TYL、ERM和ROM处于中风险,其余为低风险;乌江的RQsum为0.013,检出抗生素均处于低风险,说明水体受人类活动干扰最小.研究显示,三峡库区主要水域中抗生素含量略低于其他水域,但应进一步强化对畜禽养殖行业抗生素使用的监管,开展畜禽粪污还田技术规范中抗生素含量限制的相关研究. 相似文献
67.
近年来,燃煤电厂烟塔合一烟气排烟对近距离环境影响的不确定性,使其在国内的推广过程受到一定限制。准确判断烟塔合一排烟的环境影响,对于我国现有燃煤电厂烟气污染物的排放有着巨大的工程价值和明显的现实意义。利用国家环境保护某重点实验室中风洞试验平台,对燃煤电厂烟塔合一烟气污染物在近距离的扩散和传输行为,进行物理风洞试验以及数值模拟计算,并进行对比分析。结果表明:德国Austal2000模式的浓度预测并不精确;数值风洞也有其差异性,而物理风洞的结果在很大程度上符合现有的理论及国内工程实际。 相似文献
68.
Yitao Pan Xiaoyang Wang Leo W.Y. Yeung Nan Sheng Qianqian Cui Ruina Cui Hongxia Zhang Jiayin Dai 《环境科学学报(英文版)》2017,29(11):14-23
Phthalates are a large family of ubiquitous environmental pollutants suspected of being endocrine disruptors. Epidemiological studies have associated phthalate metabolites with decreased reproductive parameters and linked phthalate exposure with the level of urinary 5-methyl-2′-deoxycytidine(5mdC, a product of methylated DNA). In this study, adult male mice were exposed to 450 mg di-isobutyl phthalate(DiBP)/(kg·day) via dietary exposure for 28 days. Mono-isobutyl phthalate(Mi BP, the urinary metabolite) and reproductive function parameters were determined. The levels of 5mdC and 5-hydroxymethyl-2′-deoxycytidine(5hmdC) were measured in urine to evaluate if their contents were also altered by DiBP exposure in this animal model. Results showed that DiBP exposure led to a significant increase in the urinary 5mdC level and significant decreases in sperm concentration and motility in the epididymis, accompanied with reduced testosterone levels and downregulation of the P450 cholesterol side-chain cleavage enzyme(P450scc) gene in the mice testes. Our findings indicated that exposure to DiBP increased the urinary 5mdC levels,which supported our recent epidemiological study about the associations of urinary 5mdC with phthalate exposure in the male human population. In addition, DiBP exposure impaired male reproductive function, possibly by disturbing testosterone levels; P450scc might be a major steroidogenic enzyme targeted by DiBP or other phthalates. 相似文献
69.
Binghui Zheng Xiaolei Liu Rui Guo Qing Fu Xingru Zhao Shanjun Wang Sheng Chang Xing Wang Mengjiao Geng Guang Yang 《环境科学学报(英文版)》2017,29(11):97-109
In this work, a method was developed and optimized for the analysis of polyfluoroalkyl and/or perfluoroalkyl substances(PFASs) content in surface water and sediment samples with high instrumental response and good separation. Surface water and sediment samples were collected from the Yangtze River Delta(YRD) to analyze the distribution characteristics of perfluoroalkyl carboxylic acids(PFCAs), perfluoroalkane sulfonic acids(PFSAs), perfluoroalkyl phosphonic acids(PFPAs), perfluoroalkyl phosphinic acids(PFPiAs), and polyfluoroalkyl phosphoric acid diesters(di PAPs). The results showed that the total concentrations of PFCAs and PFSAs in YRD varied from 31 to 902 ng/L. PFCAs(≥ 11 carbons) and PFSAs(≥ 10 carbons atoms) were not detected in any surface water samples. The mean concentrations of all PFCAs and PFSAs in surface water from the sampling areas decreased in the following order:Yangtze river(191 ng/L) ≈ Taihu lake(189 ng/L) Huangpu river(122 ng/L) ≈ Qiantang river(120 ng/L) Jiaxing urban river(100 ng/L). Strong significant(p 0.05) correlations between the concentrations of many of the compounds were found in the sampling areas, suggesting a common source for these compounds. Only perfluorooctanoic acid(PFOA) was observed in all sediment samples, at concentrations varying from 0.02 to 1.35 ng/g. Finally, detection rates of two di PAPs were only 8% and 10%, respectively and the concentration of di PAPs was two to three times lower compared to PFCAs and PFSAs. 相似文献
70.
<正>Arsenic(As)is a well-recognized toxicant and carcinogen.Chronic exposure to inorganic arsenic causes a range of human cancers(e.g.,skin,bladder,and lung)and increases the risk of developing diabetes,hypertension,and cardiovascular and neurological diseases.The prevalence of arsenic species and the severity of their health effects continue to drive and demand for extensive research(Carlin et al.,2016). 相似文献