江苏历史时期洪涝灾害时空分布特征

以江苏历史文献记录的洪涝灾害为研究对象，分析历史时期江苏地区洪涝灾害发生的时空差异性特征，探讨影响洪涝灾害时空差异性的原因。时间尺度上，历史时期江苏地区洪涝灾害明清时期多发，集中于夏秋季节，其影响因素有长时间异常降水、风暴潮以及厄尔尼诺事件等。空间尺度上，洪涝灾害多发生于太湖平原、里下河平原及沿江地区。唐宋时期，太湖平原、沿江地区是江苏省洪涝灾害最为集中的地区，明代以降苏北平原洪涝灾害更为集中，原因应该是宋代太湖平原人口激增，涸湖造田破坏了太湖东泄水道，明清后泄洪能力得到提升，长江口的演变则使得沿江地区潮灾逐渐减少，而里下河平原因为黄河夺淮入海，导致泥沙沉降，水流不畅，成为洪涝走廊。     

Deficit analysis: service capacity assessment and planning in developing countries – case study in the Philippines

Current demand analysis methods do not formally cover the case of chronic deficits in quantity or quality of water and sanitation services. These services include drinking water supply (DWS), wastewater and sewage treatment (WST), and municipal solid waste management (MSW). Formal analysis of this case would, at minimum, define the deficit state and evaluate appropriate options for reducing it. This paper proposes for a formal analytical model for municipal sanitation systems (MSS) that operate with deficits in at least one of the constituent services of DWS, WST, or MSW. The model introduces definitions and notation for describing the deficit state for conducting demand analysis on municipal sanitation systems. This model of demand analysis for systems with chronic deficits will hereinafter be referred to as deficit analysis. A case study for Bacoor, Philippines is presented as an example.     

生态示范区内生态工业建设模式探讨

生态工业建设为生态示范区建设的重要内容之一 ,是一项涉及到地区经济发展、人地关系协调的重大举措。从生态示范区建设中生态工业的基本定义出发 ,对生态工业建设层次进行详尽分析 ;并结合代表江苏省苏南、苏中和苏北不同社会经济发展水平的三个地区——吴县市、邗江县和邳州市的具体案例 ,通过对其产业构成、主导产业、消费结构以及经济发展总量与人均水平的对比分析 ,指出经济发展水平较低的地区要立足当地农业资源 ,实施末端治理并逐步推广清洁生产这种较低层次的生态工业建设模式 ;而经济发展较好的地区其生态工业的建设则要采用生态企业以及生态工业园区这种较高层次的建设模式。为确保生态工业建设的顺利实施 ,最后从政府、企业、市场和公众四方面提出了生态工业建设的驱动机制     

人工神经网络在预测深基坑周边地表沉降变形中的应用研究

深基坑开挖引起的周边地表变形预测是一个复杂非线性问题,引起地表沉降的影响因素很多,各因素之间呈高度的非线性关系。传统的基坑用边地表沉降变形预测方法存在着一定的局限性,其预测精度有待提高,而人工神经网络是一种多元非线性动力学系统,可以灵活方便地对多成因的复杂未知系统进行高度建模,实现全面考虑各种主要影响因素的深基坑周边地表沉降变形预测。本文介绍了误差反向传播(BP)网络模型的结构、学习过程及其算法的改进,径向基函数(RBF)网络模型的结构及其学习过程;分析了影响深基坑开挖周边土体沉降变形的主要影响因素;以25个基坑工程的地表沉降实测资料为训练样本,建立了11个输入影响因素的BP神经网络模型和RBF神经网络模型,通过对样本的学习训练过程及对5个检验样本的预测精度,说明了人工神经网络用于预测基坑周边地表沉降的可行性和准确性。     

“两山”实践成效评价指标体系构建与测算

将生态环保目标(“绿水青山”)和经济发展目标(“金山银山”)称为“两山”,客观、科学地评价“两山”成效,明晰制约“两山”转化的瓶颈,对于推动“两山”实践进程至关重要.在辨析“绿水青山”与“金山银山”内涵的基础上构建了“两山”实践成效评价指标体系,并以浙江省为例,对浙江省11个城市的“两山”实践成效进行了分析.结果表明:①2008—2017年,综合发展度与“两山”指数均呈波动上升趋势,综合发展程度对“两山”指数产生重要影响,浙江省11个城市间“两山”指数区域性差异明显.②浙江省11个城市间“绿水青山”指数与“金山银山”指数排名基本呈逆向变化特征,丽水市、衢州市等“绿水青山”指数排名靠前,但“金山银山”指数排名靠后.②根据“两山”指数的分布情况,浙江省11个城市可划分为“绿水青山”保护领先型、“金山银山”建设领先型、“两山”建设相对同步型3种类型.研究显示,尽管浙江省“两山”建设已步入第三阶段,但11个城市中“两山”建设差异较大,区域发展不均衡,建议各城市要因地制宜,适时调整政策,推进“两山”实践.      

乙醇汽油对国六直喷汽油车排放特性的影响

选择5台国六直喷汽油车采用3种不同组分的E10乙醇汽油和1种不含含氧化合物的国VI汽油,按照国六排放标准开展了WLTC循环测试,研究乙醇和基础油组分对污染物排放的影响规律.结果表明,多数国六直喷汽油车的CO、THC和PM排放有所降低,NO_x排放无明显差异,PN排放微增,所有样车的CO、THC和PM平均排放降低为6%、7%和14%.E10乙醇汽油中的重质芳香烃含量增高时,PN排放明显增加,PN排放与PMI指数呈现较强的正相关关系.     

基于逸度方法分析大连湾海域PFASs在海水-沉积物界面的扩散趋势

研究污染物在沉积物-水界面的扩散趋势对于开展其环境风险评估具有重要作用。本研究基于大连湾海域海水和沉积物样品中全氟烷基化合物（PFASs）的含量数据,应用变异系数（C_v）分析了浓度分布的空间变异程度,应用逸度分数（ff）分析了PFASs在沉积物-水界面扩散趋势,应用响应系数（RC）分析了有机碳含量对扩散趋势的影响。结果表明:大连湾海域海水和沉积物中9种PFASs的总浓度均为中等变异;在沉积物中的浓度空间差异略大,可能受历史排放污染物残留及污染事故的影响。在海水-沉积物界面扩散过程中,全氟烷基磺酸类和全氟烷基羧酸类化合物呈现相同的扩散特性,总体表现为ff值随PFASs链长的增加而逐渐降低的趋势。短链PFASs在大连湾海域倾向于存在于水体中,而长链PFASs倾向于扩散到沉积物中。有机碳是影响PFASs在沉积物-水界面扩散趋势的重要参数,且对长链PFASs的影响更明显。全氟辛烷磺酸作为一种持久性有机污染物在大连湾海域中主要处于平衡状态。     

船舶溢油事故风险分析

伴随着船舶制造业和水运行业的进步和发展,船舶运输成为国内外主要的运输方式之一,是沿海经济的支柱和国家发展的标志。然而大规模的船舶运输在带来经济效益的同时势必会产生一定的负面影响,其中船舶溢油事故成为影响海洋健康发展的重要来源之一,为了保持海洋的可持续性发展,必须对船舶溢油事故进行预控。根据京唐港多年溢油事故的数据和经验,确定溢油事故模拟情景,进而评价码头前沿及航道入港口处的溢油事故,可供类似相关行业风险评估参考。     

Sulphate, Nitrogen and Base Cation Budgets at 21 Forested Catchments in Canada, the United States and Europe

To assess the concern over declining base cation levels in forest soils caused by acid deposition, input-output budgets (1990s average) for sulphate (SO₄), inorganic nitrogen (NO₃-N; NH₄-N), calcium (Ca), magnesium (Mg) and potassium (K) were synthesised for 21 forested catchments from 17 regions in Canada, the United States and Europe. Trend analysis was conducted on monthly ion concentrations in deposition and runoff when more than 9 years of data were available (14 regions, 17 sites). Annual average SO₄ deposition during the 1990s ranged between 7.3 and 28.4 kg ha⁻¹ per year, and inorganic nitrogen (N) deposition was between 2.8 and 13.8 kg ha⁻¹ per year, of which 41–67% was nitrate (NO₃-N). Over the period of record, SO₄ concentration in deposition decreased in 13/14 (13 out of 14 total) regions and SO₄ in runoff decreased at 14/17 catchments. In contrast, NO₃-N concentrations in deposition decreased in only 1/14 regions, while NH₄-N concentration patterns varied; increasing at 3/14 regions and decreasing at 2/14 regions. Nitrate concentrations in runoff decreased at 4/17 catchments and increased at only 1 site, whereas runoff levels of NH₄-N increased at 5/17 catchments. Decreasing trends in deposition were also recorded for Ca, Mg, and K at many of the catchments and on an equivalent basis, accounted for up to 131% (median 22%) of the decrease in acid anion deposition. Base cation concentrations in streams generally declined over time, with significant decreases in Ca, Mg and K occurring at 8, 9 and 7 of 17 sites respectively, which accounted for up to 133% (median 48%) of the decrease in acid anion concentration. Sulphate export exceeded input at 18/21 catchments, likely due to dry deposition and/or internal sources. The majority of N in deposition (31–100%; median 94%) was retained in the catchments, although there was a tendency for greater NO₃-N leaching at sites receiving higher (<7 kg ha^-1 per year) bulk inorganic N deposition. Mass balance calculations show that export of Ca and Mg in runoff exceeds input at all 21 catchments, but K export only exceeds input at 16/21 sites. Estimates of base cation weathering were available for 18 sites. When included in the mass balance calculation, Ca, Mg and K exports exceeded inputs at 14, 10 and 2 sites respectively. Annual Ca and Mg losses represent appreciable proportions of the current exchangeable soil Ca and Mg pools, although losses at some of the sites likely occur from weathering reactions beneath the rooting zone and there is considerable uncertainty associated with mineral weathering estimates. Critical loads for sulphur (S) and N, using a critical base cation to aluminium ratio of 10 in soil solution, are currently exceeded at 7 of the 18 sites with base cation weathering estimates. Despite reductions in SO₄ and H⁺ deposition, mass balance estimates indicate that acid deposition continues to acidify soils in many regions with losses of Ca and Mg of primary concern. The U.S. Government's right to retain a non-exclusive, royalty free licence in and to any copyright is acknowledged. The Canadian Crown reserves the right to retain a non-exclusive, royalty free licence in and to any copyright.