中国能源消费碳排放变化的驱动因素研究

将DEA中基于能源投入的Shephard距离函数引入到LMDI分解模型中,建立了1995~2010年中国6大产业能源消费碳排放7因素分解模型.研究结果显示, 产业结构效应、经济产出效应、人口规模效应、能源绩效效应对碳排放的增加具有一定的拉动作用,其中经济产出效应的累积贡献率最大为135%,产业结构效应、人口规模效应、能源绩效效应对碳排放累积贡献率分别为10.74%、9.39%、0.65%;潜在能源强度效应对碳排放下降的累积贡献率最大为54.6%,说明产业能源强度的调整空间较大,且抑制效应逐年增强;能源结构效应、能源技术进步效应对我国碳减排的累积贡献率分别为0.2%和1.04%,贡献微弱,亟待提高;从产业层面研究发现,农林牧渔业、建筑业、批发零售和住宿餐饮业和其他行业的低碳发展较好,工业、交通运输仓储和邮政业低碳发展不佳,工业始终是我国碳排放的主要来源.     

挥发性有机物处理新技术的研究

随着VOCs处理要求的不断提高,新型的VOCs处理技术日益受到关注。详细分析了生物法、光催化氧化法以及等离子体催化氧化法VOCs处理新技术的研究进展。高效微生物的筛选、新型生物填充材料的研究使生物法VOCs处理更加实用;光催化剂的表面改性有助于防止催化剂钝化,保证光催化系统的长期稳定运行;等离子体催化氧化VOCs过程中能耗的降低以及副产物的控制将是下一步研究的重点。     

保护性耕作对农田土壤有机碳库的影响

农田土壤有机碳库是陆地生态系统碳库的重要组成部分,对维持全球碳平衡具有重要意义。有机碳库的储量除了受气候和环境因素的影响外,还受农业耕作措施的影响。综述了保护性耕作对土壤有机碳库的影响,并从碳输入、碳分解和碳固持3个方面讨论了保护性耕作影响有机碳库的途径。大量实验结果表明,保护性耕作在表层土壤中能提高作物根系生物量1.0%~142.9%;增加土壤微生物的生物量2.2%~140%。免耕还显著降低土壤的呼吸强度,在0.9%~72.6%之间,从而减少碳的损失。免耕还提高了土壤团聚体数量,从而有利于有机碳在土壤中的固持。今后的研究应该在如下几方面加强：（1）加强区域性对比研究;（2）加强长期定位研究;（3）加强对固碳机理的研究;（4）建立模型加强对多种因子综合效应的研究。     

基于因素分解模型的水资源利用变动分析

残差项的存在影响了因素分解模型对水资源利用驱动效应的量化效果,论文引入无残差的对数平均迪氏分解法(LMDI),对大连市1980-2009年间的水资源利用变动进行了分析,将其影响因素分解为:定额效应、产业结构变动效应、经济规模效应及人口效应,并与常用的3种非完全因素分解模型的结果进行对比。最后选择LMDI完全分解的结果对大连市水资源利用变动的特征进行分析。结果表明:①LMDI法的分解效果最好,残差为0;②经济效应和人口效应为水资源利用的拉动效应,其中,经济效应为主要因素;定额效应和产业结构变动效应为水资源利用的抑制效应,其中,定额效应为主要因素;③2005年之后,大连市社会经济对用水的拉动进一步加剧,现有节水能力显出疲态。     

洱海湖滨带挺水植物残体腐解特征及其环境效应初探

采用试验模拟的方法,研究洱海4种主要挺水植物茭草(Zizania caduciflora)、香蒲(Typha latifolia)、水葱(Scirpus validus)和芦苇(Phragnites australis)在水体中的腐解特征. 结果表明:在21 d的腐解试验中,水葱腐解速率最快,茭草和香蒲其次,芦苇最慢; 挺水植物单位干物质TN释放量表现为水葱>茭草≈香蒲>芦苇,TP释放量表现为水葱>茭草>香蒲>芦苇; 4种植物TP释放率均高于TN,腐解出的TP进入水体的比例也明显高于TN. 水体中ρ(TN),ρ(TP)及ρ(COD_Cr)均在腐解初期(1～3 d)快速上升,pH和ρ(DO)快速下降; 随后,ρ(TN),ρ(TP)及ρ(COD_Cr)均缓慢下降,pH和ρ(DO)则缓慢回升. 结合洱海湖滨带挺水植物空间分布的调查结果,估算全湖湖滨带4种挺水植物中TN和TP的总质量分别为17.622和2.870 t,其中茭草和香蒲中的TN和TP分别占91%和95%,对茭草和香蒲进行适时、适宜的收割对改善湖滨带的水质具有重要的意义.      

脱硫石膏热分解特性及其动力学参数研究

采用热分析仪,研究了氮气气氛下分析纯石膏、干法脱硫石膏和湿法脱硫石膏的热重特性,并利用Coast-Redfern法计算了三种石膏的动力学参数。结果表明:三种石膏的分解过程可分为干燥、结晶水脱除、杂质分解和硫酸钙分解等四个阶段;三种石膏中硫酸钙的起始分解温度在1 000～1 200℃之间,且两种脱硫石膏的起始分解温度比分析纯石膏有所降低;分析纯石膏的表观活化能最大,两种脱硫石膏的活化能基本相当,分析纯石膏、干法脱硫石膏和湿法脱硫石膏的表观活化能分别为214.73,128.54,111.12 kJ/mol。     

3D geometric structures and biological activity: Application to microbial soil organic matter decomposition in pore space

During the past 10 years, soil scientists have started to use 3D Computed Tomography in order to gain a clearer understanding of the geometry of soil structure and its relationships with soil properties. We propose a geometric model for the 3D representation of pore space and a practical method for its computation. Our basic idea consists in representing pore space using a minimal set of maximal balls (Delaunay spheres) recovering the shape skeleton. In this representation, each ball could be considered as a maximal local cavity corresponding to the “intuitive” notion of a pore as described in the literature. The space segmentation induced by the network of balls (pores) was then used to spatialize biological dynamics. Organic matter and microbial decomposers were distributed within the balls (pores). A valuated graph representing the pore network, organic matter and distribution of micro-organisms was then defined. Microbial soil organic matter decomposition was simulated by updating this valuated graph. The method was implemented and tested using real CT images. The model produced realistic simulated results when compared with data in the literature in terms of the water retention curve and carbon mineralization. A decrease in water pressure decreased carbon mineralization, which is also in accordance with findings in the literature. From our results we showed that the influence of water pressure on decomposition is a function of organic matter distribution in the pore space. As far as we know, this is the approach to have linked pore space geometry and biological dynamics in a formal way. Our next goal will be to compare the model with experimental data of decomposition using different soil structures, and to define geometric typologies of pore space shape that can be attached to specific biological and dynamic properties.     

Modelling of Air Quality with CAMx: A Case Study in Switzerland

The three-dimensional Eulerian model CAMx (Comprehensive Air QualityModel with Extensions) was applied for the first time to simulate bothgaseous and particulate photochemical air pollution in Switzerland during July 28–30, 1993. The meteorological input data were prepared using the Systems Applications International Mesoscale Model (SAIMM). The CAMx model results were compared with the measurements carried out at ground level andfrom airborne measuring platforms within the frame of the Swiss POLLUMET research programme. In general, the CAMx performance for gaseous species wasfound to be better than that of the previously used Urban Airshed Model (UAM)and the Variable Grid Urban Airshed Model (UAM-V). The most significant improvement for the gaseous species is in the prediction of HNO₃ concentrations, due to the inclusion of aerosol chemistry. Aerosol species such as NO₃ ^-, NH₄ ⁺, SO₄ ^2-, and secondary organic aerosols were calculated in one particle size range (0.04–2.5 m) and compared with a few measurements available. Although July 29 was reasonably well simulated, overestimated wind speeds by SAIMM for July 30 caused a too fast transport of pollutants. Similarly to measurements, significant spatial correlation of the secondarily formed aerosols with ozone and formaldehyde is found in the afternoon.     

Polycyclic aromatic hydrocarbons (PAH) in different forest humus types

The behavior of 20 PAH in the organic layers of a L mull, an Of mull and a mor was assessed by a combined approach of a soil profile study, and the analysis of particle-size separates. Increasing PAH concentrations with depth in the mor profile (L, 866 μg kg⁻³; Of, 2902 μg kg⁻¹; Oh, 10489 ug kg⁻¹) were assigned to selective enrichment during organic matter decomposition. PAH were further highly enriched within the finer separates. For the L horizons, significant positive correlations were established between the enrichment of individual PAH (as observed from the decomposition gradient between the >2-mm fraction and the < 0.05-mm fraction), and the K_OW for each compound. The slope of the regression line, m, described the degree of differentiation between low- and high-molecular PAH during litter decomposition. Since m was greatest in the most biologically active humus type (L mull, 0.33) and smallest in the most inactive (mor, 0.20), microbial breakdown was assumed as the dominating process for this differentiation. The results also indicated that decomposition processes had already taken place in the L horizons, leading to morphological and chemical changes of organic matter, and to an enrichment of high molecular PAH.     

防火树种阻火特性的实验研究

以木荷作为防火树种 ,首先利用热重装置分别研究了其树干和枝叶的热解失重过程 ,从得到的热重曲线TG、DTG中发现 ,伴随着温度的升高 ,试样发生了三次失重高峰 ,并且 5 0 0℃时的残留物不及其初始重量的 10 %。然后在燃料床上以松针为燃料 ,分别模拟了 2 0°和 30°等小坡度情况下地表火的蔓延过程 ,通过分析热电偶记录下来的温度场分布 ,研究了火蔓延过程中防火树种在火焰和坡度作用下的阻火特性和阻火机理 ,结合其热解特性的研究 ,论证了水分析出是防火树种发挥阻火性能的关键因素 ,得到一些对生物防火技术研究有用的结论 ,为更好的利用和发展生物防火技术来预防和控制大规模森林火灾提供了理论基础。