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为探明太阳山湿地浮游植物优势功能群季节演替规律及其主要驱动因子,于2019年4月(春季)、7月(夏季)、10月(秋季)和2020年1月(冬季)采样分析了太阳山湿地浮游植物的种类组成、优势种、丰度、生物量及季节变化,同时测定了水环境理化因子指标,采用冗余分析方法研究了浮游植物优势功能群的优势度、丰度与水环境因子之间的关系。结果表明:太阳山湿地浮游植物可分为22个功能类群;优势功能群的季节演替和空间分异特征明显,存在一定的规律性。春、秋、冬3个季节的浮游植物以硅藻门为主,夏季以绿藻门和蓝藻门为主。春季优势功能群主要为D、C、P,以硅藻门种类为主;夏季优势功能群主要为J、Lo、TC、M、H1,以硅藻门、绿藻门、蓝藻门种类为主;秋季优势功能群主要为D、S1、MP,以硅藻门、绿藻门种类为主;冬季优势功能群主要为D、X3,以硅藻门种类为主。影响太阳山湿地浮游植物优势功能群季节演替的水环境因子有水温(WT)、pH、溶解氧(DO)、透明度(SD)、盐度(Sal)、氮磷营养元素含量、化学需氧量(CODCr)和高锰酸盐指数(CODMn)。4个湖区浮游植物优势功能群的时空差异与水环境因子密切相关,其中,西湖区浮游植物优势功能群的季节演替驱动因子为pH、DO、WT、总磷(TP),东湖区为pH、DO、WT、氮磷营养元素含量,南湖区为pH、DO、CODCr、五日生化需氧量(BOD5),小南湖区为pH、DO、WT、BOD5、CODCr、TP。pH、DO、WT、BOD5、SD等水环境因子的季节差异以及TP、TN、氨氮(NH3-N)、CODMn等水环境因子的湖区差异是太阳山湿地浮游植物优势功能群出现季节演替的主要原因。 相似文献
214.
Jing Bai Huijun Yao Maosheng Lin Lina Zhang Fuan Lei Xiaofei Li Junsheng Guo 《Journal of environmental radioactivity》2010,101(11):969-973
The present paper reports the biosorption of uranium onto chemically modified yeast cells, Rhodotorula glutinis, in order to study the role played by various functional groups in the cell wall. Esterification of the carboxyl groups and methylation of the amino groups present in the cells were carried out by methanol and formaldehyde treatment, respectively. The uranium sorption capacity increased 31% for the methanol-treated biomass and 11% for the formaldehyde-treated biomass at an initial uranium concentration of 140 mg/L. The enhancement of uranium sorption capacity was investigated by Fourier transform infrared (FTIR) spectroscopy analysis, with amino and carboxyl groups were determined to be the important functional groups involved in uranium binding. The biosorption isotherms of uranium onto the raw and chemically modified biomass were also investigated with varying uranium concentrations. Langmuir and Freundlich models were well able to explain the sorption equilibrium data with satisfactory correlation coefficients higher than 0.9. 相似文献
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Noreen Brennan Thomas M Van Rensburg Cyril Morris 《Journal of Environmental Planning and Management》2017,60(11):1967-1992
Although international trade in energy may offer a flexible and cost effective means by which European countries could meet their renewable energy targets, developers in the exporting nation can face local opposition for reasons which are not always clear. Using focus groups and a public survey, we contrast perspectives between local stakeholders and wind farm operators and investigate the community impacts associated with large-scale wind energy for domestic use and export from Ireland to the UK. Although the export of renewable energy from Ireland to the UK is currently on hold, our findings suggest that significant investment is required by the state and wind farm operators in better information provision, trust building, effective instruments to internalise wind farm externalities and co-management arrangements before Ireland can fully capture the benefits of wind exports to the UK. 相似文献
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Non‐native plants have invaded nearly all ecosystems and represent a major component of global ecological change. Plant invasions frequently change the composition and structure of vegetation communities, which can alter animal communities and ecosystem processes. We reviewed 87 articles published in the peer‐reviewed literature to evaluate responses of arthropod communities and functional groups to non‐native invasive plants. Total abundance of arthropods decreased in 62% of studies and increased in 15%. Taxonomic richness decreased in 48% of studies and increased in 13%. Herbivorous arthropods decreased in response to plant invasions in 48% of studies and increased in 17%, likely due to direct effects of decreased plant diversity. Predaceous arthropods decreased in response to invasive plants in 44% of studies, which may reflect indirect effects due to reductions in prey. Twenty‐two percent of studies documented increases in predators, which may reflect changes in vegetation structure that improved mobility, survival, or web‐building for these species. Detritivores increased in 67% of studies, likely in response to increased litter and decaying vegetation; no studies documented decreased abundance in this functional group. Although many researchers have examined effects of plant invasions on arthropods, sizeable information gaps remain, specifically regarding how invasive plants influence habitat and dietary requirements. Beyond this, the ability to predict changes in arthropod populations and communities associated with plant invasions could be improved by adopting a more functional and mechanistic approach. Understanding responses of arthropods to invasive plants will critically inform conservation of virtually all biodiversity and ecological processes because so many organisms depend on arthropods as prey or for their functional roles, including pollination, seed dispersal, and decomposition. Given their short generation times and ability to respond rapidly to ecological change, arthropods may be ideal targets for restoration and conservation activities. Efectos de las Plantas Invasoras sobre los Artrópodos 相似文献
217.
盐龙湖水源生态净化系统FG和MBFG演替特征及水质响应性评价 总被引:1,自引:1,他引:0
为探究水源生态净化系统水质净化及浮游植物控制效能,并评价FG(functional group,FG)和MBFG(morphology-based functional group,MBFG)两种功能群对水源生态净化系统内部环境以及水质响应的有效性,于2018年夏季对盐龙湖生态净化系统各单元出水水质和浮游植物功能群进行监测分析.结果表明,盐龙湖生态净化系统能够有效净化水质,进水总磷、总氮、溶解氧和浊度的平均值分别为0.20 mg·L~(-1)、 1.91 mg·L~(-1)、 2.88 mg·L~(-1)和60.23 NTU,经系统处理后分别为0. 09 mg·L~(-1)、 0.95 mg·L~(-1)、 6.26 mg·L~(-1)和39.53 NTU.同时,系统内部水质的空间分布具有异质性,其中溶解氧(DO)、酸碱度(pH)和浊度的空间差异显著(P0.001).盐龙湖生态净化系统在出水处于轻度富营养状态下仍能够有效控制浮游植物密度(4.42×10~5~4.32×10~6cells·L~(-1)),降低水华风险.研究期间绝对优势FG功能群有5个:B、 P、 TC、 J和W1,绝对优势MBFG功能群有6个:GroupⅠ、 GroupⅢ、 GroupⅣ、 GroupⅤ、 GroupⅥ和GroupⅦ,两种绝对优势功能群都能够有效指示生境条件的变化.RDA分析表明MBFG功能群的环境解释度要高于FG功能群.研究结果表明,选择MBFG分类法研究夏季盐龙湖生态净化系统中浮游植物的动态来了解生境的变化更合适. 相似文献
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219.
采用傅里叶变换衰减全反射红外光谱法(ATR-FTIR)研究北京西北城区灰霾天气下PM_(2.5)中有机官能团(R-OH羟基、R-CH脂肪族碳氢基、R-CO-羰基、R-NO2硝基官能团)和无机离子(NH_4~+、SO_4~(2-)、NO_3~-)的变化规律.结果表明,PM_(2.5)中无机离子(NH_4~+、SO_4~(2-)、NO_3~-)的ATR-FTIR吸收峰值高于有机官能团(R-CH,R-CO-,R-NO_2,R-OH)的峰值;有机官能团R-CH的吸收峰峰值高于R-CO-和R-NO_2官能团的吸收峰,R-OH官能团的吸收峰峰值最低.灰霾天PM_(2.5)中各有机官能团和无机离子的ATR-FTIR吸收峰值明显高于非灰霾天.说明灰霾天气下PM_(2.5)中这些官能团及无机离子的质量浓度均高于非灰霾天.灰霾天PM_(2.5)中无机离子(NH_4~+、SO_4~(2-)、NO_3~-)质量浓度高于有机官能团(R-CH,R-CO-,R-NO_2,R-OH)的质量浓度,且有机官能团以R-CH为主,R-CO-,R-NO_2次之,R-OH最少. 相似文献
220.
Introduction: Due to the myriad of unique characteristics associated with motorcycle operation, motorcycle safety is a public health concern as complex as it is serious. National crash data suggest motorcyclists are 28 times more likely to be killed when compared to passenger car occupants. In the state of Florida, motorcycle crashes are 1.5 times more likely to result in the death of the rider, placing Florida among the top deadliest states for motorcyclists in the nation. Using police-reported data from 2016, this study addresses the complex and interconnected nature of the many characteristics associated with motorcycle operation by investigating the effect of age on motorcyclists’ riding behavior as it relates to injury severity for single-motorcycle crashes in the state of Florida. Method: To account for unobserved heterogeneity in the crash data, mixed logit models with heterogeneity in means and variances were estimated to model three injury severity outcomes (non-visible, severe, and fatal) for three age groups (under 30, 30–49, and 50 and above). Results: Model results indicate that age affects motorcyclists’ safety perception and ability to assess risks, thereby influencing their involvement in risky behaviors. Characteristics unique to motorcycle operation—spatial characteristics, speed, motorcycle type, time of day, helmet usage, alcohol consumption, ejection from motorcycle, passenger presence, endorsement status, and lighting—are further complicated by their dependency on the characteristics of the individual motorcyclist. Age of motorcyclist indicates a relationship between motorcyclists’ behavior and perceived safety. Conclusion: The model results indicated that statistically significant parameters constituted different models and they were not equal across the age groups of motorcyclists: aged under 30, aged 30–49, and aged 50 and above. Through advanced econometric modeling, this study fills a gap in the existing literature and assists the safety professionals, motorcycle trainers, policymakers, law enforcement agencies, and roadway designers in developing countermeasures. 相似文献