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121.
The study investigated the origin, quality, composition, and trophic state of sedimentary organic matter (SOM) in core samples collected from three zones (Munambam, Vypin, Chettuva) of Central Kerala, India. The SOM exhibited enhanced levels for carbohydrate (CHO) followed by protein (PRT) and lipid (LPD); and phytopigment in the sediment followed the trend: Pheophytin (Pheo) > Carotenoid (carotend) > Chlorophyll-a (Chl-a) > Chlorophyll-b (Chl-b) > Chlorophyll-c (Chl-c). The low PRT: CHO ratio indicated a large amount of nonliving or aged organic matter in the sedimentary environment. Whereas the low Chl-a: Pheo ratio interprets the abundance of dead plant materials in the sediments. Correlation matrix showed strong association between organic matter and clay fraction of sediment. Furthermore, the strong interrelationships between biochemical components and chloropigments in all the zones suggested that SOM is strictly connected to phytodetritus deposition. Vypin zone near Vallarpadam Container Terminal revealed the presence of high biopolymeric carbon content. Besides, the PRT: CHO > 1 reflected the eutrophic condition at the same site but the low PRT: CHO ratio in the remaining stations displays the oligotrophic nature.  相似文献   
122.
基于臭氧检测仪(Ozone Monitoring Instrument,OMI)的遥感数据,利用ArcGIS10.2对2005—2020年中三角地区(湖北省、湖南省、江西省)紫外吸收性气溶胶指数(Ultraviolet Aerosol Index,UVAI)的时空变化进行分析,结合气溶胶颗粒物(PM2.5、PM10)和气态污染物(CO)数据,利用HYSPLIT(Hybrid Single-Particle Lagrangian Integrated Trajectory model)方法研究主要污染城市气溶胶颗粒物的来源与传输路径,通过核密度估计法、相关性分析、聚类分析,研究其影响因素.结果表明:(1)在空间分布上,中三角地区吸收性气溶胶的高值区集中在襄阳市北部、孝感市东部、武汉市西部;在时间分布上,2008年UVAI最低,2014年达到最大值;季节分布具有明显变化,2005—2020年吸收性气溶胶指数季均值为冬季>春季>秋季>夏季.(2)UVAI与人口增长率、第二产业产值占总产值的比重呈正相关性,与节能环保预算支出呈显著负...  相似文献   
123.
本文对北京等华北中部5站1956至1985年旱涝成因进行了分析讨论.结果表明,区域性旱涝主要是在海洋和局地土壤热状况异常作用下产生的.对华北中部而言,冬季黑潮海温与局地地温变化是引起汛期旱涝变异最重要的原因.前期下垫面热源异常对后期旱涝影响往往是通过累积的异常加热造成环流形势和系统的异常而实现的.海温与地温影响降水的机制不同,前者的影响是大尺度的,而后者的影响只是区域性的.当海温异常造成的大尺度环流变化与局地热状况都有利于降水时.洪涝更容易发生,反之易旱.  相似文献   
124.
中央生态环境保护督察是党中央、国务院推进生态文明建设和生态环境保护工作的重大制度创新。《中央生态环境保护督察工作规定》于近期正式出台,首次以党内法规形式明确了生态环境保护督察的制度框架、程序规范、权限责任等。从发展历程来看,我国生态环境保护督察大致经历了督企为主、督政督企并举、党政同责三个阶段。生态环境保护督察具有突出政治站位、压实责任,坚持问题导向、强化震慑,突出边督边改、取信于民等基本特征。为强化成果应用,全面准确把握当前我国生态环境保护工作的重点难点,本文设置7个一级指标和18个二级指标对首轮中央生态环境保护督察所指问题的分布特征进行统计分析,初步剖析问题产生原因,并从督察对象、督察内容和督察体制方面对第二轮中央生态环境保护督察进行了展望。  相似文献   
125.
In Ethiopia, not only farmers but also the public and private sector partners are still hesitant to invest in sustainable land management (SLM). This study focuses on the Central Rift Valley and explores the potential for co-investments in SLM, where public and private sector partners support farmers with material, capital, knowledge, etc. A survey revealed current bottlenecks for co-investments and requirements needed to collaboratively invest in SLM. It covered 165 public sector partners (micro-, meso- and macro-level institutions) and 42 private sector partners (banks, exporters and local traders). Results for the public sector show a gap between macro- and micro-/meso-level actors concerning co-investments in SLM. Macro-level institutions do not acknowledge the bottlenecks identified by micro- and meso-level institutions (e.g. lack of accountability, top-down approaches and lack of good leadership). Similarly, opinions on requirements for co-investments in SLM differ considerably, showing that bridging the institutional micro–macro gap is crucial to co-investments. Most factors are related to the wider governance context and to different perceptions among micro- and macro-level actors as to the critical pre-conditions to co-investment in SLM. Improving governance at all institutional levels, capacity building and enhancing a common understanding on barriers to SLM is required. Results for the private sector reveal that economic bottlenecks limit possibilities to co-invest in SLM, and that enabling policies in the public sphere are required to trigger private investments. Hence, the potential for co-investments in SLM is available in Ethiopia at micro- and meso-level and within the private sector, but profound commitment and fundamental policy changes at the macro-level are required to exploit this potential.  相似文献   
126.
This paper presents research currently being conducted in Central Queensland, Australia to understand conflicts between coastal zone resource users and the associated sociocultural and political issues surrounding coastal zone management. Conflict occurs between stakeholders in the coastal zone over values, conservation and development trade-offs, access, and resource use rights. Decisions are currently made within a multi-stakeholder framework where there is limited understanding among stakeholders of each groups values and aspirations, and few, mechanisms for negotiation, or to ensure transparency of decisions and feedback on consultation. This paper reports on the contribution of stakeholder analysis and social mapping to conflict management and findings from their application. As it is applied here, stakeholder analysis and social mapping have been successful participatory tools used to document and feed back the values, interests, attitudes and aspirations of stakeholders. Understanding stakeholder conflict is essential in progressing a whole catchment approach to decision-making that secures the cooperation of a diverse range of social groups.  相似文献   
127.
Forest degradation in the tropics is often associated with roads built for selective logging. The protection of intact forest landscapes (IFL) that are not accessible by roads is high on the biodiversity conservation agenda and a challenge for logging concessions certified by the Forest Stewardship Council (FSC). A frequently advocated conservation objective is to maximize the retention of roadless space, a concept that is based on distance to the nearest road from any point. We developed a novel use of the empty‐space function – a general statistical tool based on stochastic geometry and random sets theory – to calculate roadless space in a part of the Congo Basin where road networks have been expanding rapidly. We compared the temporal development of roadless space in certified and uncertified logging concessions inside and outside areas declared IFL in 2000. Inside IFLs, road‐network expansion led to a decrease in roadless space by more than half from 1999 to 2007. After 2007, loss leveled out in most areas to close to 0 due to an equilibrium between newly built roads and abandoned roads that became revegetated. However, concessions in IFL certified by FSC since around 2007 continuously lost roadless space and reached a level comparable to all other concessions. Only national parks remained mostly roadless. We recommend that forest‐management policies make the preservation of large connected forest areas a top priority by effectively monitoring – and limiting – the occupation of space by roads that are permanently accessible.  相似文献   
128.
以中原城市群强市-新乡市为例,介绍城市环境噪声的声源构成主要以工业噪声和社会生活噪声为主。随着城镇化规模的扩大,近年来的噪声监测值总体呈下降趋势,但道路交通噪声和社会生活噪声有增高趋势。结合声环境质量现状,提出了合理规划功能区布局、加强声环境管理、利用城市绿地降低噪声、提高单体建筑规划设计水平等改善对策措施。  相似文献   
129.
• 90% total COD, 95.3% inert COD and 97.2% UV254 were removed. • High R2 values (over 95%) for all responses were obtained with CCD. • Operational cost was calculated to be 0.238 €/g CODremoved for total COD removal. • Fenton oxidation was highly-efficient method for inert COD removal. • BOD5/COD ratio of leachate concentrate raised from 0.04 to 0.4. The primary aim of this study is inert COD removal from leachate nanofiltration concentrate because of its high concentration of resistant organic pollutants. Within this framework, this study focuses on the treatability of leachate nanofiltration concentrate through Fenton oxidation and optimization of process parameters to reach the maximum pollutant removal by using response surface methodology (RSM). Initial pH, Fe2+ concentration, H2O2/Fe2+ molar ratio and oxidation time are selected as the independent variables, whereas total COD, color, inert COD and UV254 removal are selected as the responses. According to the ANOVA results, the R2 values of all responses are found to be over 95%. Under the optimum conditions determined by the model (pH: 3.99, Fe2+: 150 mmol/L, H2O2/Fe2+: 3.27 and oxidation time: 84.8 min), the maximum COD removal efficiency is determined as 91.4% by the model. The color, inert COD and UV254 removal efficiencies are determined to be 99.9%, 97.2% and 99.5%, respectively, by the model, whereas the total COD, color, inert COD and UV254 removal efficiencies are found respectively to be 90%, 96.5%, 95.3% and 97.2%, experimentally under the optimum operating conditions. The Fenton process improves the biodegradability of the leachate NF concentrate, increasing the BOD5/COD ratio from the value of 0.04 to the value of 0.4. The operational cost of the process is calculated to be 0.238 €/g CODremoved. The results indicate that the Fenton oxidation process is an efficient and economical technology in improvement of the biological degradability of leachate nanofiltration concentrate and in removal of resistant organic pollutants.  相似文献   
130.
中亚黄土是研究区域古气候和古环境变化的重要载体。但是对于受到广泛研究的黄土 高原黄土来说,对中亚东部塔城黄土的报道较少。基于对塔城黄土粒度的系统分析,与伊犁盆 地黄土、典型黄土高原的黄土对比,我们发现无论是粒度频率曲线、粒度结构散点图、还是三 角图,塔城黄土与伊犁盆地清水河黄土较相似,而与黄土高原黄土不同,塔城黄土粒度频率分 布曲线为三峰分布,粒度组成比较分散,分选较差,细、中颗粒含量较少,主要以粗颗粒物质 为主,属近源风成黄土。结合当地地形和现代环流分析,我们认为中亚萨雷耶西克阿特劳沙漠 为塔城黄土提供主要的物源,盛行西风为粉尘的搬运提供足够的动力,向西开口的山间盆地地 形为粉尘的沉积提供有利的沉积中心,这三个条件的共同作用导致了塔城盆地厚层黄土的沉积。  相似文献   
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