博斯腾湖表层沉积物元素地球化学特征及重金属污染评价

重金属是沉积物中一类非常典型的污染物,开展湖泊沉积物元素地球化学的研究具有重要的现实意义。本文对新疆博斯腾湖表层沉积物(0—5 cm)中24种元素含量、粒度、有机碳含量(TOC)等进行了系统分析。受干旱区强蒸发作用的影响,博斯腾湖沉积物Ca、Sr、Mg含量高于新疆土壤元素背景值,Al、Fe、Mn及重金属元素等低于新疆土壤元素背景值。Al、K、Fe及重金属等元素主要受陆源细颗粒物质影响(4μm、4—16μm),Ba、Na受粗颗粒含量(63μm)影响,Ca、Sr、Mo、TOC主要来源于湖泊内生作用,与16—63μm颗粒组分相关。Q型聚类将采样点分为3个区域,第Ⅰ区为包括河口区、湖心区及东部湖区的大部分湖区,第Ⅱ区为湖区西侧黄水沟区,第Ⅲ区为湖区东南角。在空间上,重金属元素与细颗粒组分分布基本一致,而第Ⅱ区部分地区沉积物重金属已受到流域农田排水的影响。总体来说博斯腾湖沉积物重金属元素基本不构成污染。本研究可为湖泊沉积物元素地球化学研究提供参考,对博斯腾湖流域环境管理与规划也有重要价值。     

Application of Bayesian Regularization Artificial Neural Network in explosion risk analysis of fixed offshore platform

Computational Fluid Dynamics (CFD) is routinely used in Explosion Risk Analysis (ERA), as CFD-based ERA offers a good understanding of underlying physics accidental loads. Generally, simplifications were incorporated into CFD-based ERA to limit the number of simulations. Frozen Cloud Approach (FCA) is a frequently used simplification in the dispersion part of the CFD-based ERA procedure. However, its accuracy is questionable in the complex and congested environment such as offshore facility. Furthermore, in explosion part, some specific techniques, e.g. linear/double bin-interpolated techniques have been proposed while the corresponding accuracy is still unknown since the developers did not yet check their accuracy by considering the explosion computational data as the benchmark.This study presents a more accurate algorithm, namely Bayesian Regularization Artificial Neural Network (BRANN) and accordingly proposes the frameworks regarding BRANN-based models for the CFD-based ERA procedure. Firstly, the framework is proposed to develop the Transient-BRANN (TBRANN) model for transient dispersion study. In addition, the framework to determine the BRANN model for explosion study is developed. The proposed frameworks are explained by a case study of the fixed offshore platform. Consequently, this study confirms the more accuracy of the TBRANN model over FCA and the accuracy of BRANN model for CFD-based ERA.     

韶石山- -丹霞地貌丹霞山的姐妹山

广东北部丹霞盆地是中、新生代内陆山间盆地，由早第三纪红色岩层构成的丹霞山和韶石山，是丹霞地貌命名标准地区的姐妹山。韶石山因舜帝南巡奏韶乐而得名，后为韶关市命名的主山。自古以三十六奇石著称于世。近年已逐步开发和开展旅游活动。     

基于空间聚类的中国东北气候分区及其气象干旱时间变化特征

近50年来,中国东北地区干旱化趋势明显,越来越频繁的干旱事件对该区域人民的生产和生活造成了严重的影响。基于1961-2016年中国地面降水和气温月值0.5°×0.5°格点数据,利用空间系统聚类方法对中国东北进行气候分区,通过标准化降水指数探讨了中国东北各亚区气象干旱的时间演变规律,并结合小波功率谱和小波全谱分析了各亚区干旱的周期变化特征。结果表明：（1）空间上,可将东北地区分为8个气候亚区,即西辽河平原半干旱农牧区、吉辽东部山地湿润农林区、呼伦贝尔高原半干旱牧业区、东北中部半湿润—半干旱农牧区、黑吉东部山地湿润农林区、大兴安岭北部湿润林业区、呼伦贝尔—黑河湿润—半湿润农林区、三江平原湿润农业区;（2）不同亚区的干旱事件时间演变特征存在明显差异,但大致都经历了3个干旱时期：1960s后期、1970s中后期至1980s前期、1990s后期至2000s;2000-2010年间东北地区干旱发生频率和影响范围最大,尤其是中、西部;（3）不同亚区干旱变化主要存在11年和3~8年的显著周期,第一主周期差异明显。研究结果对于弄清楚中国东北各亚区特有的气候变化驱动因素、制定气候均质区域干旱监测计划和水资源的管理具有重要的现实意义。     

城市环境噪声测量中布点数的优化研究

应用主成分分析,模糊聚类概念及动态规划方法对环境噪声测量的布点数进行优化研究。所建立的模型试用于厦门市环境噪声布点数的优化研究。     

Evaluating the Potential for Conservation Development: Biophysical, Economic, and Institutional Perspectives

Abstract:  The widespread conversion of rural land to low-density residential development poses an immediate threat to biodiversity and to the provision of ecosystem services. Given that development will continue and environmental stakes are high, analyzing alternative growth strategies is critical. Conservation development is one such strategy that has the potential to benefit ecosystems and diverse stakeholders including developers, homebuyers, governments, and society as a whole. Conservation development clusters homes on one part of a property to manage the most ecologically important land for the conservation of biodiversity and ecosystem services. We draw on lessons learned from landscape ecology, open-space development, and regional planning to weigh the biophysical, economic, and institutional evidence for and against conservation development. Conservation development offers many potential environmental and economic advantages: relatively high home values and appreciation rates, lower development costs, and social and ecological benefits to society including landscape connectivity, protection and active stewardship of important ecological assets, and the maintenance of ecosystem services. But this approach also has shortcomings: it may require enlightened institutional regulations and regional planning (and/or ecologically aware developers), it is not always more profitable than conventional development and thus may require subsidies or incentives, and additional research is required to fully understand its benefits and drawbacks. With more information on the effects of clustering, the development of flexible zoning laws, and effective regional planning, conservation development could be a viable strategy for sustaining biodiversity and ecosystem services in changing landscapes.     

Habitat association studies in conjunction with adaptive cluster samples

Habitat association studies investigate the relationships between habitat characteristics and animal usage of study regions. These studies are often conducted in conjunction with surveys designed primarily to estimate population totals. This paper shows that habitat association studies may proceed from surveys using adaptive cluster sampling. The manner in which units appear in the sample turns out not be relevant to the habitat association study, which proceeds as though the units came from a simple random sample. However, it is also shown that the information about the habitat association parameters is greater than one would expect from a simple random sample of the same general size.     

运用聚类分析划分农业生态类型区

科学地划分农业生态类型区对于分类指导农业生产、合理利用农业资源具有重大的现实意义。本文通过相关分析,选择了包括自然本底、经济条件、生态环境和生态经济效益在内的26个指标,采用聚类分析的方法,把全省划分为四个生态类型区,即山区林地生态区(Ⅰ)、盆地丘陵生态区(Ⅱ)、水网平原生态区(Ⅲ)和沿海岛屿生态区(Ⅳ)。在分区的基础上,分别对各生态类型区进行了综合评述。     

农村环境质量区划的多元分析

本文提出了适合于农村环境质量区划的分区方法，即首先以主成分分析法分析农村环境质量问题，然后以多种聚类分析法取得一个初始分区系统，最后用判别分析法判别该初始分区系统中各区域单元的类型归属是否正确，对一些类型归属不恰当的作适当调整，最终得到农村环境质量分区系统。文章最后讨论了类型划分问题。     

一个液相化学反应机理的建立和应用

利用比较积分反应速率的方法,建立了一个简化液相化学反应机理ARCML,并在各种大气状况下以及各种物理参数下对ARCML作了验证.然后利用ARCML模拟光化学烟雾形成初期的云水酸化过程,结果表明,自由基氧化s(Ⅳ)在污染或高NO_x的大气中非常重要.