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本文以贵阳市公众为研究对象,采用问卷调查法、数理分析法、相关分析法对贵阳市公众生态文明认知特征及影响因素进行分析。结果表明:贵阳市公众对生态文明概念了解程度一般,大部分人表示非常愿意接受生态文明教育,在遇到不文明行为时,大部分人持观望或无所谓态度。文化程度和职业是影响公众对生态文明概念认知程度的主要因素。性别和职业分别是影响是否接受生态文明教育态度和反对不文明行为态度的重要因素。建议贵阳市全面提高公众受教育程度、加大生态文明宣传力度、鼓励公众参与生态文明建设活动。 相似文献
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基于博弈论组合赋权的流域水资源承载力集对分析 总被引：1，自引：0，他引：1
针对受多种不确定性因素影响的流域水资源承载力评价问题,提出评价指标与标准等级之间的四元联系度模型。采用梯形模糊数定量表示差异度不确定性系数连续变化过程,建立了集对分析与梯形模糊数耦合的水资源承载力评价模型。用层次分析法确定各评价指标主观权重后,从属性效用值出发由熵权理论赋予客观权重,同时,由博弈论集结模型优化组合主客观权重,通过计算以置信区间形式表示的加权联系数,确定水资源承载力的等级标准。耦合模型相对极大熵原理法及模糊综合评判法灵敏度高,更能真实地反映出流域水资源系统本身承载力大小以及偏离分级标准的程度。实例研究结果表明,该模型方法思路清晰,过程直观,评价结果实效合理,具有较好的推广应用前景。 相似文献
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张雅萱 《中国农村水利水电》2023,(3):60-68+73
区域水资源承载力的衡定和底线约束是生态安全、区域和谐发展的前提和基础，是影响地区经济发展的主要因素，对于国土空间规划的完善具有至关重要的作用。人类生活的各方面生产需要皆依赖于水条件的控制，水资源面临的形式愈发严峻。传统的水资源承载力评价多基于静态描述并划分等级，对水资源承载能力大小的认识还有欠缺。以秦岭山区某县为研究区，在阅读文献、收集数据和实地调查的基础上，运用能值生态足迹理论，借助“以水四定”原则对水资源承载力做出评价，计算和分析了该县区2017-2020年的水生态足迹、水生态承载力和生态盈亏状况，以及水资源影响下的地区发展指标容量，并使用ArcGIS对生态足迹数据空间分布进行可视化表达，选用障碍度模型对影响水资源承载力的障碍因子进行了识别，最后对水资源合理布局方向做出科学优化。研究表明，该地区水资源供给略大于需求；水资源生态足迹空间分布高值区多在中心区域；人均水资源生态足迹、污水生态足迹和生态用水生态足迹是影响水资源承载力提升的主要障碍因子；优化方向上应根据水资源分布调整产业结构以发展特色产业。科学利用水资源对保证经济发展至关重要，只有合理调度水资源利用导向，明确水资源承载力，提... 相似文献
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基于"物理Wuli—事理Shili—人理Renli"方法论(WSR)构建水资源承载力评价理论体系,并运用"熵值—耦合协调度"分析方法,对2006-2015年河北省水资源承载力进行综合评价。研究结果表明:2006-2015年河北省水资源承载力和各系统间的耦合协调度整体呈上升趋势,其中:2006-2008年增幅较大;2008-2010年增幅趋缓并有回落;2010-2014年呈上升趋势;2014-2015年有所回落。系统内3个子系统整体上也均呈上升趋势,其中,"技术管理"子系统波动较大。另外,反应产业结构以及科技治污水平的"铅排放总量占废水排放总量比"、"工业废水治理设施日均处理能力"、"万元工业增加值用水量"是影响该地区水资源承载力的重要因素。研究方法具有实用性,可为区域水资源评价和管理提供科学依据。 相似文献
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吐鲁番地区水资源-经济-生态耦合协调发展分析 总被引：1，自引：0，他引：1
以吐鲁番地区为例,依据耦合协调度模型评价了2001-2013年该地区的水资源-经济-生态环境耦合协调发展状况。研究表明:1随着社会经济发展,吐鲁番地区水资源-经济-生态环境耦合协调发展状况也向着优质耦合的方向发展;22001-2006年吐鲁番地区的经济发展滞后,但水资源和生态环境的综合评价指标较高,2006-2008年该地区经济发展速度较快,水资源和生态环境能与经济较为协调,2009-2013,经济发展和生态环境需水给水资源供应造成了一定压力:3从2001-2013年,该地区的水资源,经济和生态环境的综合评价指数一直处于上升态势,说明在该地区,水资源和经济及生态环境协调发展是有很大空间的。但近年来,水资源形势比较严峻,建议应提高整体污水处理,提高用水效率,加大中水回用力度,促进区域整体协调发展水平的提升。 相似文献
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水价是引导水资源合理配置,促进节水型社会建设的有效手段之一。公众参与水价制定是供水方、用水方和政府共同参与,既能够客观全面反映水资源价值、供水成本、环境成本在内的,又能充分代表用水方利益的新型水资源价格形成模式。应用公众参与水价制定理论,以新疆石河子市为例,通过抽样问卷调查、分析、综合评价等途径对研究区生活用水进行了定价探析。结果表明：公众参与制定的石河子市生活用水水价更能反映其水资源的稀缺性,通过宣传教育来逐步提高现状水价,充分利用价格杠杆的约束效应来构建节水型社会是该市当前水务改革的重点。 相似文献
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《中国农村水利水电》2017,(6)
水电站中长期优化调度对于提高水资源利用效率具有重要作用,但采用定出力系数造成优化模型的计算结果不够精细。针对这一问题,通过出力系数的影响因素分析,选取水库水位和发电流量(或出力)为主要影响因子,再应用厂内负荷优化分配模型推求出力~水库水位~综合出力系数关系,并应用于水电站中长期发电优化调度数学模型。经棉花滩水电站长系列计算表明:该方法与定出力系数法的多年平均发电量相差4.34%;出力系数变化规律更符合生产实际。因此,该方法对于开展水电站中长期精细化管理具有较好的参考作用。 相似文献
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Adoption of a new technology, such as irrigation, is a complex phenomenon. Several factors of economic and social nature contribute to the farm-level decisions affecting adoption. In this study, the role played by attitudes of potential adopters towards irrigation and its subsequent adoption on their farm unit was estimated. Two models were estimated, one incorporating only adopters' socio-economic characteristics, and the other, only their attitudes towards irrigation. Results suggest that adopters' attitude, particularly with respect to economic and environmental effects of irrigation, were significant determinants of their decision to proceed with adoption of irrigation, and have a role to play in adoption of irrigation over and above that explained by socio-economic characteristics. In particular, these results suggest that negative perceptions with respect to economics of irrigation and those related to its detrimental impacts on environmental quality, particularly through soil salinity, may be significant deterrents for adoption of irrigation. The study suggests that planning of large scale water development projects, particularly those involving irrigation, must be cognizant of attitudes of potential adopters. Furthermore, during the planning stages, more attention should be paid to the development of proper educational programs, as well as extension packages, to ensure that potential adopters formulate correct attitudes towards the new technology. 相似文献
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数学作为一门基础性学科，在学生的各个学习阶段都起到了不可替代的作用，在工科院校中数学教学的重要性更是升到了一个新的高度。通过数学的学习，可以培养学生的应用能力和探究思维，通过对数学知识的学习和灵活运用，学生的综合能力会得到系统性的提高。对于数学的教学工作，应当做到有针对性、有目标，在教学工作中，充分做到对症下药、有的放矢，让学生通过对数学的学习，提高自身的综合能力，更好地为社会建设贡献力量。 相似文献
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分析了四川简阳地区砂岩和土壤中的水分运动特性和砂岩中储存的水分对土壤水分补给量的多少。对当地的砂岩和土壤进行了水分特征曲线的测定试验、入渗试验和蒸发试验,并采用研究中常用模型对试验结果进行了拟合,通过对拟合结果的分析,得出了当地土壤和砂岩的水分特性,总结出了该地区表面土层在缺水时水分很容易被下部砂岩层补给,砂岩中的水分是作物利用的重要水资源的结论。这对于充分利用当地水资源,合理确定类似地质条件地区灌溉定额,解决无灌溉条件丘陵区作物缺水问题,实现农业节水灌溉有一定的参考价值。 相似文献
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G. L. Hammer J. W. Hansen J. G. Phillips J. W. Mjelde H. Hill A. Love A. Potgieter 《Agricultural Systems》2001,70(2-3):515-553
Agricultural ecosystems and their associated business and government systems are diverse and varied. They range from farms, to input supply businesses, to marketing and government policy systems, among others. These systems are dynamic and responsive to fluctuations in climate. Skill in climate prediction offers considerable opportunities to managers via its potential to realise system improvements (i.e. increased food production and profit and/or reduced risks). Realising these opportunities, however, is not straightforward as the forecasting skill is imperfect and approaches to applying the existing skill to management issues have not been developed and tested extensively. While there has been much written about impacts of climate variability, there has been relatively little done in relation to applying knowledge of climate predictions to modify actions ahead of likely impacts. However, a considerable body of effort in various parts of the world is now being focused on this issue of applying climate predictions to improve agricultural systems.
In this paper, we outline the basis for climate prediction, with emphasis on the El Niño-Southern Oscillation phenomenon, and catalogue experiences at field, national and global scales in applying climate predictions to agriculture. These diverse experiences are synthesised to derive general lessons about approaches to applying climate prediction in agriculture. The case studies have been selected to represent a diversity of agricultural systems and scales of operation. They also represent the on-going activities of some of the key research and development groups in this field around the world. The case studies include applications at field/farm scale to dryland cropping systems in Australia, Zimbabwe, and Argentina. This spectrum covers resource-rich and resource-poor farming with motivations ranging from profit to food security. At national and global scale we consider possible applications of climate prediction in commodity forecasting (wheat in Australia) and examine implications on global wheat trade and price associated with global consequences of climate prediction.
In cataloguing these experiences we note some general lessons. Foremost is the value of an interdisciplinary systems approach in connecting disciplinary knowledge in a manner most suited to decision-makers. This approach often includes scenario analysis based on simulation with credible models as a key aspect of the learning process. Interaction among researchers, analysts and decision-makers is vital in the development of effective applications — all of the players learn. Issues associated with balance between information demand and supply as well as appreciation of awareness limitations of decision-makers, analysts, and scientists are highlighted. It is argued that understanding and communicating decision risks is one of the keys to successful applications of climate prediction.
We consider that advances of the future will be made by better connecting agricultural scientists and practitioners with the science of climate prediction. Professions involved in decision making must take a proactive role in the development of climate forecasts if the design and use of climate predictions are to reach their full potential. 相似文献
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S.H. KimM. Fan S.O. Prasher R.M. PatelS.A. Hussain 《Agricultural Water Management》2011,98(4):653-660
Pesticides degrade principally through biodegradation processes, whereas antibiotics kill microorganisms or inhibit their growth in soils and thus may affect the fate of pesticides. In this study, the impact of antibiotics on the degradation of atrazine in a sandy soil is investigated in lysimeters over a ninety-day period. Four treatments, monensin, narasin, salinomycin and non-antibiotic, were assigned in triplicate to twelve PVC lysimeters. Both soil and leachate samples were collected and analyzed at predetermined time intervals. In all treatments, atrazine was found to leach down through the soil profiles with the concentration level decreasing with depth, and only trace amounts of atrazine were found in the leachate. However, the statistical analysis of the results showed that all the three antibiotic treatments yielded a significantly slower dissipation of the atrazine level as compared to the non-antibiotic treatment; the mass balance analysis indicated an increased half-life of atrazine in the presence of antibiotics. 相似文献
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北京典型灌区土壤和农产品多氯联苯污染风险评估 总被引：5，自引：0，他引：5
为明确北京东南郊灌区表层土壤和农作物多氯联苯(PCBs)含量和污染水平以及人体健康风险,2015年在该灌区采集了20个土壤样品和28个作物样品,利用气相色谱-质谱联用仪分析了样品中7大类PCBs含量。研究结果表明,灌区表层土壤PCBs质量比为ND(低于检出限)到0.711 776μg/kg,均值为0.43μg/kg,总体上土壤PCBs含量随污灌历史年限增加而增加。本研究区表层土壤PCBs含量处于较低水平,土壤未受到PCBs污染且其生态风险概率均小于10%。灌区采集的冬小麦籽粒、大葱、茄子、梨、白薯、芥蓝PCBs含量均低于实验检出限,未检出;夏玉米籽粒、菜心和油菜PCBs总量分别为0.17~0.47μg/kg、1.63μg/kg和5.91μg/kg。不同污灌历史年限并未显著影响夏玉米籽粒PCBs含量。本研究区农产品PCBs含量处于较低水平,均低于美国卫生及公共服务部建议限量。采集的土壤和农产品样品仅四氯联苯含量高于实验检出限,能检测出;一氯联苯到三氯联苯和五氯联苯到七氯联苯均低于实验检出限,未检出。本研究中成人和儿童PCBs致癌风险分别为8.49×10-7和4.66×10-7,非致癌风险分别为1.41×10-1和3.88×10-1,均低于US EPA规定限值,说明PCBs未对人群产生明显的健康危害。致癌危害和非致癌危害均以口-作物(玉米和蔬菜)为主,其对人体健康所造成的风险占总个人年风险的比例分别为99.79%~99.95%和99.81%~99.94%。 相似文献
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沈阳市既是重工业城市,也是农业大市,发展现代农业必须依靠科技进步。在介绍沈阳市农业发展现状及农业科技条件的基础上,探讨科技进步在沈阳农业发展中的重要作用,并根据沈阳市的实际情况展望今后科技进步的发展方向,为加快沈阳市的农业发展提供理论参考。 相似文献
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针对野生刺五加叶片中黄酮含量的测量方法繁琐、时间较长及需破坏叶片等问题,提出了一种基于高光谱技术对不同时段的刺五加叶片中黄酮含量的估算模型。首先,分析提取地域、年龄、长势相近的20株刺五加叶片光谱特征,通过对叶片进行烘干、磨粉及利用紫外分光光度计等化学方法测得叶片中黄酮的真实含量,并选择4种预处理互相结合、比较的方式,判断出最优预处理模型;通过SPA与PCA算法的结合,选择出较明显的特征波段,通过MatLab2018a将特征波段的反射率分别与40组预测集验证相关性后,再分别选取预测值和20组实测值与BP神经网络、支持向量机进行模型建立。实验结果表明:利用BP神经网络建立的模型的校正集决定系数Rc2分别为0.8649、0.7976、0.8485,支持向量机建立的模型的校正集决定系数Rc2分别为0.7526、0.7742、0.7243,证明SNV和1 Der结合的预处理方式与BP神经网络所构建的模型效果最好。研究为高光谱技术对刺五加叶片中黄酮的反演提供了有力的支持,也会提高工业和药用采摘的效率及刺五加的利用价值。 相似文献
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Targeted sampling of water was performed in streams, the river mouth, and the municipal drinking-water tap in the vicinity of San Francisco, South Leyte, Philippines. Samples were processed on site and transported back to Sweden for analysis by gas chromatography mass spectrometry to identify and quantify the pesticides commonly used in the area. Collaborations were initiated with employees at the local Department of Agriculture and Municipal Disaster Coordinating Council to learn more about the rice cultivation in this area and times for spraying. Detectable levels of pesticides λ-cyhalothrin, cypermethrin and deltamethrin (0.0005-1.4 μg/L) were found in representative water samples. In 47% of samples the detected levels exceeded the recommended limit values for pesticides in surface water according to Swedish guidelines (Swedish Chemicals Agency, 2008). The analysis of samples taken at the river mouth revealed measurable levels of λ-cyhalothrin and cypermethrin, which means that residues of pesticides applied to rice paddy fields were shown to end up at the river mouth. The success of the sampling and analysis methods was confirmed by the data which was in accordance with the expected effect of dilution from day to day. Variable levels of insecticides in the river and all the way down to the sea may have adverse health effects on people using the water and on the aquatic environment, including sensitive coral reefs. This situation is applicable not only to the Philippines, but also to the whole of Southeast Asia, with approximately 70% of their human population living in coastal areas. As Southeast Asia encompasses approximately 34% of the world's coral reefs and between a quarter and a third of the world's mangroves, as well as the global biodiversity triangle formed by the Malay Peninsula, the Philippines, and New Guinea, the need to reduce the impacts of marine pollution in this region is of great importance. 相似文献