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1.
The newly formed extensive flooded land associated with the Three Gorges Reservoir hold great potentials to provide ecosystem services (ESs) for surrounding cities and communities. Conflicting values and conventional management strategies may complicate and inhibit broad-scale decision-making for this novel ecosystem. Public attitudes are a crucial influence in the way this process plays out. This study was conducted to assess how the reservoir bank is perceived by the general public of Chongqing Municipality in terms of importance of riparian ESs, and preference for corresponding landscape design styles through photo-questionnaire interviewing. Although Chongqing citizens know little of the “ecosystem services” concept, they do recognise riparian environmental and ecological benefits especially the bank protection and pollution interception functions, while benefits of habitats for wildlife and flood attenuation were of less concern. Recreational values were least appreciated, which is inconsistent with other studies. This may be attributed to a wider, intensive environmental education in various social media in today’s China. But publicity has been dominated by toxic air, water and soil pollution control rather than the benefits of nature conservation and personal contact with nature. In line with recognition of ESs, there is quite strong preference for the forested design scenario and particularly vegetation components across the socio-demographic spectrum. Overall, socio-demographic variables have very low explanatory power for the perceptual responses. Our study also revealed misunderstandings around riparian functions and a gap between public expectations and special abiotic and biotic prerequisites in restoring novel ecosystems. Finally, we discuss the relevance of this research to urban novel ecosystems in general, and implications for raising public awareness, engaging appropriate public values in sustainable design and management of such ecosystems.  相似文献   
2.
2018年4月10日、6月11日、8月14日在桓仁水库的上游(江南九队)、中游(砬砬岗子)和下游(泗河大地)3个站位用500 mL具塞磨口瓶盛装采水器采集的水库水样,进行限制性营养盐原位试验,同时测定水中溶解氧和初级生产力,并检测分析水体理化指标,以查明辽宁桓仁水库氮磷分布、营养盐限制和初级生产力状况,保护桓仁水库生态系统的结构和功能完整性。试验结果显示,营养盐加富试验中,0.5 mg/mL氮+0.3 mg/mL磷的添加组可显著提高水体中的溶解氧水平(P<0.05);上游和中游氮磷比为2∶1、下游氮磷比为4∶1可显著提高水体中的溶解氧水平(P<0.05);初级生产力随季节变化特征明显,原始P/R系数均小于试验组。根据试验结果分析得知,桓仁水库营养盐限制因素受季节变化的影响显著,具有氮、磷双限制等特征;根据初级生产力判断桓仁水库为自养代谢型水体。  相似文献   
3.
魏晋南北朝时期中原的战乱促使河北山东等地的世家大族及流民纷纷迁徙到辽西地区,此地的人口数量大为增加,且带来了中原地区的先进生产技术。十六国时期,先后统治辽西地区的前燕、后燕、北燕三个地方政权对农业的重视和发展,加之优越的生态环境和悠久的农耕基础,辽西农业在耕作技术、作物的种类、水利灌溉等方面都有了较快发展,且带动了慕容鲜卑由畜牧经济向农耕经济的转变。农业生产虽受自然灾害和战争等因素的限制但整体上呈现波浪式发展。  相似文献   
4.
三峡库区沉积物中重金属化学形态分布特征与相关性分析   总被引:1,自引:1,他引:0  
为全面了解三峡库区干支流沉积物中重金属的赋存形态,更好地为评价及保护三峡库区水生态环境提供科学依据,于2015年6月在三峡库区采集沉积物样品67个,通过ICP-MS等仪器测定了沉积物中各重金属元素的不同赋存形态量,运用SPSS、Matlab统计分析软件对重金属赋存形态进行对比分析。结果表明,库区表层沉积物中Cr、Ni元素主要以残渣态为主(占总量的75%以上);Cu、Zn、As元素主要以残渣态和可还原态为主(合计占总量80%~95%);Cd元素主要以酸可提取态和可还原态为主(分别占总量的55%和23%);Pb元素主要以可还原态和残渣态为主(各占总量的71%和18%)。Cd和Pb元素生物可利用态量较高,均超过该元素的长江沉积物背景值;该种形态下的重金属元素容易进入水体,并且在地球化学条件变化时转化成能被生物吸收和利用的形态,对生物造成较大危害。干流上游段重庆主城区及下游段,渠系河、大宁河、磨刀溪、沿渡河应当是重金属生态危害研究与防治的重点区域。  相似文献   
5.
Abstract Diel changes in littoral fish assemblage were studied in four reservoirs in the Czech Republic (Central Europe). The sampling was performed by beach seining in an unstructured littoral zone. Perch, Perca fluviatilis L., roach, Rutilus rutilus (L.), bream, Abramis brama (L.), carp, Cyprinus carpio L., ruffe, Gymnocephalus cernua (L.), pikeperch, Sander lucioperca (L.), eel, Anguilla anguilla (L.) and A. brama × R. rutilus hybrids exhibited higher densities at night. Only bleak, Alburnus alburnus (L.) exhibited higher densities during the day. The number of species was higher in night hauls, and mean body size of roach and bleak was also higher at night. Diel changes in fish densities resulted in the change in species composition between day and night. The study has implication for the sampling design to assess littoral fish assemblages using beach seine netting and recommends night sampling for a representative assessment or sampling during both diel periods for a robust assessment.  相似文献   
6.
用三氮脒以3.5 mg/kg的剂量对患有附红细胞体病的藏獒进行肌肉注射,隔日用同等剂量的三氮脒肌肉注射,24 h后,藏獒发生以神经症状为主的中毒现象,并表现出食欲废绝,后肢发软,四肢抽搐呈划水状,卧地不起,昏迷,体温正常临床症状。经血清生化检验,藏獒的尿素氮、肌酸激酶等的生化指标明显升高,血糖降低占病例的100%。经过5 d的药物治疗后,中毒藏獒基本恢复健康。  相似文献   
7.
Sandstone massifs with their deep ravines or gorges offer the instructive opportunity to study the response of organisms to steep environmental gradients. In 2008–2010, many groups of soil fauna were studied along transects across three ravines in the Bohemian Switzerland National Park (north-western Czech Republic), a part of the Elbe Sandstone Massif. Each transect included five sampling positions: two opposite edges, two opposite mid-slope positions, and the ravine bottom. The ravines had a specific microclimate characterized by temperature inversion. In general, the cooler and more humid ravine bottoms had also less acid soil with lower carbon content but enriched by litter of deciduous trees and herbs. The other transect positions were characterized by spruce (mid-slopes) and pine (edges) stands with mor humus, exposed to drought in the upper parts. The soil animal communities (identified to species level) differed substantially in dependence on their position along the transects. Ravine bottoms hosted a diverse soil fauna, including a rich macrofauna. The thick duff layer of acid soils on the slopes and edges hosted a poorer fauna but supported high densities of important decomposers such as enchytraeids, oribatid mites and microbivorous nematodes. In general, these were higher on the slopes, presumably due to the drought exposure of the edges. Vertical position in the ravine and soil pH were the most important factors explaining community composition. This confirmed that the area's high geomorphological diversity, leading to steep microclimatic gradients and heterogenous soil conditions, is a major cause of its high biodiversity. A shift in community structure in the lower parts of the ravines, observed after the first half of the study period, was possibly caused by summer flash floods. An increased frequency and severity of dry spells and flash floods due to heavy rains, predicted by relevant climate warming scenarios, will probably have an detrimental effect on the ravines'soil fauna.  相似文献   
8.
某水库建设项目地质灾害危险性评估   总被引:2,自引:0,他引:2  
通过野外调查、室内分析研究了评估区的地质环境条件,主要包括环境地质、水文地质和工程地质;结合建设项目可行性研究报告、岩土工程勘察报告,对某水库建设项目地质灾害危险性进行了现状评估、预测评估以及综合性分区评估;对拟建场地进行了适宜性评价,并提出了地质灾害防治措施。  相似文献   
9.
为缩短产品研制周期、增强企业竞争能力,逆向工程技术也正逐步从其他产品设计制造业领域引入到我国农业机械领域。以统收式采棉机的采摘部件梳齿为测绘对象,通过逆向工程技术,采用青岛雷顿数控设备有限公司生产的先进的NC(865)型三坐标测量仪进行扫描与测绘,获取了梳齿的点云数据,然后对其进行预处理、多边形阶段处理、参数化处理,最终运用SolidWorks软件绘制出三维模型,完成了梳齿部件的逆向设计。通过实例运用,证实了逆向工程技术在农业机械研究领域的可行性,其研究结果将对我国农业机械化的发展起到积极的推动作用。  相似文献   
10.
“三严三实”思想内容丰富,对我国各级领导干部的作风与工作提出了更新的要求,要真正的为人民谋福利,必须要深刻发扬出党的优良作风,“三严三实”的思想与践行社会主义核心价值观有着密切的关系,两者的本质是有机统一的,同时,落实“三严三实”的思想是践行社会主义核心价值观的一项需求。文章主要针对现阶段广大农村落实“三严三实”与践行社会主义核心价值观核心构建的关系与具体途径进行分析。  相似文献   
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