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111.
Glen C. Filson 《Journal of Agricultural and Environmental Ethics》1993,6(2):165-184
This paper provides an analysis of a 1991 survey of the views of a stratified random sample of 1,105 Ontario farmers. Factor analysis, Kruskal—Wallis one-way ANOVA, chi-square and correlations were used to identify differences in farmers' attitudes toward rural environmental issues as a function of their demographic and farm characteristics. Younger, well-educated farmers, especially if female, were most concerned about the seriousness of rural environmental degradation. The largest operators expressed the greatest support for the use of agricultural chemicals, were most opposed to government conservation regulations and were least environmentally oriented. Such differences between Australian and Ontario farmers as the former's greater cautiousness about governmental regulation and receptivity to the Green Movement are a function of differing demographic and farm characteristics between Australia and Ontario. 相似文献
112.
Henry L. Garie Alan McIntosh 《Journal of the American Water Resources Association》1986,22(3):447-455
ABSTRACT: A study of benthic macroinvertebrate community composition was conducted at eight sites along Shabakunk Creek, a small stream in Mercer County, New Jersey, which receives urban runoff. The relationship between changes in substrate composition and the nature of the benthic macroinvertebrate community has been examined. Organisms were collected seasonally from natural substrates in riffles. Attempts to employ artificial substrates for invertebrate collection proved unsuccessful, as the population on the samplers was not representative of that in the stream bed. Number of total benthic macroinvertebrate taxa collected declined from 13 in relatively undeveloped upstream areas to four below heavily developed areas, while population density decreased simultaneously in the same areas. Periphyton samples collected from natural substrates were analyzed for selected heavy metals. Significantly higher heavy metal concentrations are reported from substrates sampled below heavily developed areas, and changes in these values are discussed with regard to changes in benthic macroinvertebrate distribution. 相似文献
113.
生态环境导向的开发模式是解决传统生态治理项目公益性强而经济效益较差的重要手段。本研究总结了“EOD+PPP”模式、投资人+EPC模式、ABO模式、政府专项债券和创新型贷款模式等五项模式的特点与应用案例,并从地方政府支出角度剖析了各种模式的适用条件。本文认为,当前 EOD模式的运行难点包括:产业培育周期较长,投资回报不确定性较大;开发存在诸多风险因素,缺少标准化制度体系;金融机构缺乏积极性,配套投融资考评体系建设不足。最后提出 EOD模式创新的政策建议,通过关联产业一体化实施、协同生态价值实现机制、强化风险管控评估、规范应用投融资模式为完善EOD投融资模式创新提供思路。 相似文献
114.
迟学芳 《中国环境管理干部学院学报》2006,16(1):96-98
“两课”教学中的时政环节为“两课”教学走出困境提供了现实可能性。它在培养学生的辩证思维方式,增强学生的时代责任感和历史使命感,促进学生正确价值观的形成以及导入新课,提高学生自信心和活跃“两课”课堂气氛等方面都起到了积极的推动作用。可以说,时政教学是增强“两课”教学时代性和感召力的重要环节。 相似文献
115.
简易、快速检测有机磷农药的酶片和生色基质片 总被引:12,自引:0,他引:12
研制出简易、快速检测有机磷农药的酶片和生色基质片。用胆碱酯酶抑制试验检测水中的有机磷农药,检测灵敏度在0.01—10mg/L范围,适宜温度在25—35℃之间,分析周期约为15—20min。甲胺磷和水胺硫磷等硫代磷酸酯类农药经溴水活化后检测灵敏度也达上述水平。实际水样检测表明,检样中农药含量在检测灵敏度范围内时,阳性结果相当明显,溶液吸光度比值A对照/A检样>2。由于检测时无需配制试剂和使用仪器,本法特别适宜于现场检测。 相似文献
116.
Tad T. Brunyé Elena Andonova Chiara Meneghetti Matthijs L. Noordzij Francesca Pazzaglia Rasmus Wienemann Caroline R. Mahoney Holly A. Taylor 《Journal of environmental psychology》2012
Three studies test whether the southern route preference, which describes the tendency for route planners to disproportionately select south- rather than north-going routes, can be attributed to regional elevation patterns; specifically, we ask whether this effect replicates in three topographically disparate international regions, one of which is characterized by higher elevations to the north and lower to the south (Padua, Italy), and two characterized by higher elevations to the south and lower to the north (Enschede, Netherlands; Sofia, Bulgaria). In all cases, we found strong evidence that route planners disproportionately select south- rather than north-going routes at rates exceeding chance. We conclude that the southern route preference is driven by strong associations between canonical direction and perceived effort of route traversal; these effects are somewhat perplexing given that such associations are not founded in the reality of physical space. 相似文献
117.
以木糖为碳源采用间歇培养方式,对木糖厌氧发酵产酸进行研究。考察木糖浓度和初始pH值对木糖厌氧产酸的影响。结果表明,随着木糖浓度的增加,总产酸量得到提高,但木糖利用率却呈现下降的趋势。当木糖浓度为5 g/L时,其利用率为100%,15 g/L时利用率为73.9%,此时挥发性脂肪酸(VFAs)为9.22 g/L。木糖的分批投加可有效促进产酸,尤其是促进乙酸浓度的提高。pH为5.0和6.0左右时,VFAs主要成分为乙酸和丁酸;而pH为7.0~9.0时,乙酸含量明显增高,在pH值为8.0的条件下乙酸含量占总VFAs的80.1%。在pH=8.0时经过8 d左右的发酵,VFAs浓度可达9.34 g/L。 相似文献
118.
119.
用石英砂、石灰、水泥和铝粉等材料制作人工湿地填料,并对自制填料、粉煤灰块和钢渣等6种填料的等温吸附特性进行研究,发现自制填料在较低与较高浓度P溶液中吸附率都最高,在P浓度为(10~50 mg/L)时,平均吸附率达96.8%,其次是粉煤灰和钢渣,分别为87.6%和85.4%;填料对P的理论饱和吸附量分别为:自制填料(2 413.6 mg/kg)>粉煤灰块(1 605.8 mg/kg)>钢渣(1 277.5 mg/kg)>碎砖(451.6 mg/kg)>碎石(182.5 mg/kg)>砾石(18.4 mg/kg);填料中金属矿物成分含量高、比表面积大,是除P效果好的原因。 相似文献
120.
秦皇岛城市旅游CTIS形象设计研究 总被引:2,自引:0,他引:2
在日趋激烈的国际城市旅游竞争中,若想取得一席之地,旅游城市需要构建系统的城市形象识别系统,即CTIS。城市CTIS系统需要在明确的市场定位基础上,通过构建旅游城市核心理念识别系统、行为识别系统及视觉识别系统实现。在对秦皇岛旅游市场进行STP(市场细分—目标市场选择—市场定位)分析的基础上,提出秦皇岛建设"健康之都"的城市定位,并且构建了相关城市CTIS系统内容。 相似文献