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811.
812.
Although humans are a major mechanism for short and long distance seed dispersal, there is limited research testing clothing as a vector. The effect of different types of material (sports vs hiking socks), or different items of clothing (boots, socks, laces vs legs) or the same item (socks) worn in different places on seed composition were assessed in Kosciuszko National Park, Australia. Data was analyzed using Repeated Measures ANOVA, independent and paired t-tests, Multi-dimensional Scaling Ordinations and Analysis of Similarity. A total of 24,776 seeds from 70 taxa were collected from the 207 pieces of clothing sampled, with seed identified from 31 native and 19 non-native species. Socks worn off-track collected more native seeds while those worn on roadsides collected more non-native seeds. Sports socks collected a greater diversity of seeds and more native seeds than hiking socks. Boots, uncovered socks and laces collect more seeds than covered socks and laces, resulting in 17% fewer seeds collected when wearing trousers. With seeds from over 179 species (134 recognized weeds) collected on clothing in this, and nine other studies, it is clear that clothing contributes to unintended human mediated seed dispersal, including for many invasive species. 相似文献
813.
通过熏气的方法,比较了在硫氧化物混合污染气体的作用下,木本花卉(月季Rosa chinensis,杜鹃Rhododendron simsii,一品红Euphorbia pulcherrima,茉莉花Jasminum sambac),一、二年生花卉(一串红Salvia splendens,凤仙花Impatiens balsamina),宿根花卉(君子兰Clivia miniata),室内观叶植物(文竹Asparagus setacens,吊兰Chlorophytum comosum,沿阶草Ophiopogon bodinieri,朱蕉Cordyline fruticosa,吊竹梅Zebrina pendula,白斑万年青Dieffenbachia bowmannii)中13种花卉植物的叶片伤害症状及植物抗性表现,并对植物受害后的恢复情况进行了追踪观察。发现在同种污染气体的作用下,不同种类的植物表现出不同的伤害症状。植株不同叶龄的叶片对污染气体的敏感性存在一定的差异,幼龄叶不一定比中老龄叶敏感性强。当污染浓度不超过一定阈值时,花卉植物都有不同程度的恢复能力。利用“花卉植物叶片伤害评价系统”对试验植物叶片伤害症状进行了评价,依据评价结果,对试验植物进行了抗性分级。为保证对植物抗性等级划分的准确性,建议制定统一的熏气浓度标准和评价标准。 相似文献
814.
Kiyoaki Kitamura Kiyoshi Miyajima Tadashi Higashitani Norihide Nakada Koya Komori Yutaka Suzuki 《Journal of the American Water Resources Association》2009,45(1):22-34
Abstract: The objective of this study is to evaluate the effect of estrogens on fish endocrine disruption in river water and treated wastewater. Endogenous estrogen estrone (E1), 17β‐estradiol (E2), river water, and treated wastewater were used for exposure tests on male Japanese medaka. Vitellogenin induction in male medaka was regarded as the endpoint of endocrine disruption. The effective concentrations of E1 and E2 on vitellogenin induction in medaka were evaluated by breeding medaka for 14 days in tanks with various concentrations of E1 or E2. Vitellogenin induction increased with elapse of time during exposure, with higher estrogen concentrations causing greater vitellogenin induction. According to the test results, the lowest observed effect concentrations (LOECs) of E1 and E2 were estimated to be 31.6 and 5.0 ng/l, respectively; and the E2 equivalent (EEQ) LOEC value of E1 was 5.2 ng‐E2/l, derived by multiplying the relative potency of E1 by that of E2 as estimated in this study. In continuous exposure tests using river water or treated wastewater, the estrogenic activity, an index of total estrogenic potential measured by yeast screen assay and expressed as EEQ, varied widely during the exposure tests, and significant vitellogenin induction was observed after several days of high levels of estrogenic activity in water. Vitellogenin concentration tended to significantly increase if EEQ exceeded the level of 5 ng‐E2/l. The threshold value was substantially the same as the results for E1 and E2 exposure tests of medaka. Consequently, EEQ over 5 ng‐E2/l was revealed to have the potential to cause endocrine disruption of male medaka. As estrogenic activity exceeding 5 ng‐E2/l was observed in some rivers in Japan, total estrogenic potential needs to be further decreased at wastewater treatment plants to prevent fish endocrine disruption. 相似文献
815.
An educational project on biological monitoring of air quality was launched in 2004 to involve about 650 young students (age
6 to 16) from 21 schools of nine municipalities in Tuscany (Central Italy) in active detection of the crucial pollutant ozone
with indicator sensitive tobacco seedlings. Results implied the reading of 9,300 raw biological figures and were fortified
by the data captured by six photometric analysers. Under the guidance of their teachers, the students had several opportunities
to practice with many basic and applied study areas and were initiated into the scientific method in a simple and absorbing
manner. Curiosity and involvement were widespread; a sort of emotional and responsible relationship was developed by several
pupils. Though primarily an educational exercise, the survey introduced a research element and the regional picture of air
pollution that emerged has increased our knowledge of the air quality situation in the area. Biological monitoring of air
quality is a powerful tool to improve the awareness and involvement in key topics of environmental education. In addition,
it represents a crucial element for improving the awareness of problems and implies the active participation of citizens in
the assessment of several indicators of the state of the environment. Its potential as a robust implement in landscape and
urban planning is noteworthy. 相似文献
816.
817.
818.
污水处理厂清洁生产评价指标体系的构建 总被引:1,自引:0,他引:1
运用层次分析法(AHP)根据污水处理厂自身的特点构建其清洁生产的评价指标体系模型,对于评价指标权重值的获得及考核的计算方法也作出了说明,期望能对污水处理厂的清洁生产起到推动作用。 相似文献
819.
对城市污水处理厂各处理单元释放的挥发性硫化物(VSCs)进行长期监测,评估VSCs带来的感官效应和健康风险.结果表明,从浓度上看,VSCs以H2S为主(监测期间的H2S浓度为N.D.~580μg/m3),而甲硫醇(MT)的浓度占比最少(监测期间MT的浓度为N.D.~4.7μg/m3),同时VSCs的浓度分布具有明显的季节性,即夏季>秋季>冬季.在感官方面,H2S是所有VSCs中气味贡献最大的气体(贡献率为79%~93%),除二沉池外,其在其他处理单元中均为关键性恶臭气体;虽然MT浓度水平低,但是其对气味的贡献不能被忽略;格栅、沉砂池混合气体气味活性值(SOAV)分别为2591.9、5494.8,预处理单元对该厂的气味贡献最大.在健康风险方面,春季和夏季时,格栅和沉砂池中的H2S存在非致癌风险. 相似文献
820.
Runyao Huang Jin Xu Li Xie Hongtao Wang Xiaohang Ni 《Frontiers of Environmental Science & Engineering》2022,16(9):117