骨炭粉对Cd污染农田的修复效果与稳定性评价

为了探明骨炭粉对Cd污染土壤的修复效果及稳定性,以潮土与红壤Cd污染农田土壤为对象,基于土壤Cd有效态、作物降Cd率（DR,%）及降Cd失活率（IR,%）等指标,研究田间条件下施用3种浓度（0.25%、0.50%及1.0%）骨炭粉对Cd污染土壤的修复效果及120,360d后修复效果的稳定性.结果表明：骨炭粉处理均能有效促进潮土与红壤中作物生长,增加作物产量.施用骨炭粉能不同程度提高土壤中pH值、阳离子交换量（CEC）、全磷及有效磷含量;其中,0.5%和1.0%骨炭粉处理均显著（P<0.05）提高土壤pH值、土壤全磷及有效磷含量.与对照相比,不同骨炭粉处理120d后潮土和红壤中有效态Cd含量分别降低32.1%~48.4%、32.8%~56.2%,360d后土壤中有效态Cd仍然显著低于对照,降幅为26.9%~37.8%、25.8%~39.5%.对修复后三季作物Cd吸收测定结果表明,与对照相比,不同浓度（0.25%~1.0%）骨炭粉处理的第一季作物降Cd率（DR_-Cd）分别达36.0%~60.4%、33.9%~58.2%,作物降Cd率随骨炭粉施用量增加而增加.基于降Cd失活率（IR_-Cd）对骨炭粉修复效果的稳定性测定结果表明,潮土与红壤施用骨炭粉360d后,第三季作物降Cd失活率IR_-Cd为21.2%~34.7%和6.2%~21.6%,表明在酸性红壤中修复效果的稳定性大于潮土.综上骨炭粉对Cd污染土壤的修复效果及其稳定性结果表明,骨炭粉在Cd污染农田土壤修复中具有较大应用价值.     

舰艇舱室挥发性有机化合物采集方式对比测试研究

目的 准确查明某型舰艇任务期间密闭舱室空气中挥发性有机化合物(VOCs)的浓度状况,并对多种VOCs采样方式进行对比测试研究.方法 分别采用苏码罐、Tenax TA管、DNPH管等3种采样方式对舰艇不同舱室部位的VOCs进行现场采样,在实验室回溯定量分析.结果 共检测出包括烷烃、芳香烃、烯烃、卤代烃、醇类、酯类、醛酮类等物质在内的39种VOCs组分,其中的12种具有较高浓度水平,达到102μg/m3数量级以上.由于采样方式和原理的不同,检测出的VOCs种类数量和浓度含量存在差异,Tenax TA管和DNPH管的VOCs采样分析浓度普遍低于苏码罐,应当是由吸附过程中穿透导致.结论 在舰艇舱室环境VOCs测试研究中,需加强对检测结果的对比验证,注重多种采样分析方法的组合运用,实现采样分析能力的优势互补.     

Testing spatial cluster occurrence in maps equipped with environmentally defined structures

We propose a novel tool for testing hypotheses concerning the adequacy of environmentally defined factors for local clustering of diseases, through the comparative evaluation of the significance of the most likely clusters detected under maps whose neighborhood structures were modified according to those factors. A multi-objective genetic algorithm scan statistic is employed for finding spatial clusters in a map divided in a finite number of regions, whose adjacency is defined by a graph structure. This cluster finder maximizes two objectives, the spatial scan statistic and the regularity of cluster shape. Instead of specifying locations for the possible clusters a priori, as is currently done for cluster finders based on focused algorithms, we alter the usual adjacency induced by the common geographical boundary between regions. In our approach, the connectivity between regions is reinforced or weakened, according to certain environmental features of interest associated with the map. We build various plausible scenarios, each time modifying the adjacency structure on specific geographic areas in the map, and run the multi-objective genetic algorithm for selecting the best cluster solutions for each one of the selected scenarios. The statistical significances of the most likely clusters are estimated through Monte Carlo simulations. The clusters with the lowest estimated p-values, along with their corresponding maps of enhanced environmental features, are displayed for comparative analysis. Therefore the probability of cluster detection is increased or decreased, according to changes made in the adjacency graph structure, related to the selection of environmental features. The eventual identification of the specific environmental conditions which induce the most significant clusters enables the practitioner to accept or reject different hypotheses concerning the relevance of geographical factors. Numerical simulation studies and an application for malaria clusters in Brazil are presented.     

基于投入视角的黄淮海平原农业碳排放与经济发展脱钩研究

农业增长对资源依赖的变化趋势以及农业发展与环境的互动关系日益引起学术界的关注.运用脱钩理论,以2000-2005和2005-2010年为时间尺度,以县域为空间尺度,探讨黄淮海平原农业碳排放与经济增长之间的脱钩关系,揭示两者脱钩发展的时间和空间演变趋势及转移特征,并尝试分析脱钩的内在机理.结果表明:(1)脱钩类型的数量结构和空间格局均发生明显变化,黄淮海平原农业正处于由资源依赖向技术依赖的过渡时期.2000-2005年农业碳排放与经济增长以强复钩和扩张性复钩为主,脱钩空间格局较为分散;2005-2010年以强脱钩和弱脱钩为主,脱钩区域呈现空间集聚态势;若考虑因技术进步带来的碳排放系数变化因素,脱钩趋势将会更加明显.造成这种空间格局的原因主要是经济增长与环境的关系较为复杂,经济发展、技术进步和制度创新等因素通过互动机制共同作用于农业生产经营主体.(2)脱钩类型的转换呈跳跃性,转换方式以强复钩、扩张性复钩转换为强脱钩、弱脱钩为主,且脱钩状态不稳定,持续脱钩难度较大.脱钩状况受到经济效应、技术效应和政策效应等因素的共同作用,3者作用的两面性是持续脱钩难的重要原因.     

Effects of design parameters on performance and cost analysis of combined ultraviolet-biofilter systems treating gaseous chlorobenzene based on mathematical modeling

A conceptual mathematical model was used to evaluate the design parameters of a combined ultraviolet (UV)-biofilter system, and perform a cost analysis. Results showed that the UV light source strength and the gas residence times in the UV system (UVRT) and biofilter (EBRT) had positive effects on the overall chlorobenzene removal efficiency of the system. High ratio of UVRT to EBRT improved the removal efficiency, suggesting that the UV system has a greater effect on the overall performance of the system compared with the biofilter. Analysis of the capital and operating costs showed that the capital costs of the standalone biofilter system were much higher than those of the standalone UV system. However, the biofilter operating costs were lower than those of the UV system. The operating costs of the combined UV-biofilter system increased with increasing UVRT/EBRT ratio, whereas its capital costs decreased.     

风电场生命周期CO2排放核算与不确定性分析

提出了风力发电技术生命周期能耗和CO2排放核算的详细方法.应用上海某风电场数据进行核算,结果认为,风机生产阶段能耗和CO2排放占风电场生命周期能耗和CO2排放的比例均为最大,分别为68.23%和67.18%.不确定性分析认为,在所有强度参数中,钢生产综合能耗最为灵敏.风电场能耗强度和CO2强度分别为3.24gce/(kW?h)和9.47g/(kW?h),明显低于300MW火力发电机组的相同指标,分别为330gce/(kW?h)和915g/(kW?h). 20a服役期的50MW风电场满期后,同比300MW火电机组少排放CO2约234万t.     

微波法处理高浓度氨氮废水

对微波技术处理高浓度氨氮废水进行研究,分别考察了pH值、微波作用时间、曝气与否、初始氨氮浓度对去除率的影响。研究结果表明:pH和微波作用时间是影响氨氮去除率的关键因素,曝气可增强氨氮的去除率效果;浓度为500 mg/L的氨氮废水,在pH为10,微波作用时间为4 min时,曝气去除效果较好,去除率可达81.7%。     

Finding regulation among seemingly unregulated populations: a practical framework for analyzing multivariate population time series for their interactions

The structure of ecological communities is often thought to be strongly influenced by population interactions. The interactions are often labeled as bottom-up and top-down control. Previous approaches to identify these processes often assume each population in the community is itself regulated. Therefore, each time series follows a stationary process. However, complex community structure and a lack of regulation in an individual population can result in inappropriate inferences based on traditional statistical approaches. Here, we introduce a statistical framework to analyze potentially non-stationary time series that are collectively regulated. We demonstrate the method with catch-per-unit-effort time series data of selected populations in the Gulf of Mexico. In the Gulf, we found that most of the time series data, which span 26 years, were non-stationary, thus individually unregulated. Species interaction patterns were location-dependent, but where brown shrimp interacted significantly with other species, we identified significant bottom-up forcing. On the other hand, we find almost no evidence of top-down forcing throughout the study areas.     

企业碳中和行动的驱动力与模式

碳中和已成为我国气候治理和可持续发展的重要目标。尽管碳中和是国家面向2060年的长期愿景,尚未转换成针对企业的政策约束,但全球很多企业已经快速响应,主动制定自身的碳中和战略。本文从企业环境行为的驱动理论出发,分析了企业做出碳中和承诺的内部和外部驱动因素,论证了企业"化被动为主动"、自主实行碳中和战略,不但有助于在未来更加严格的气候政策规制中获得先机、赢得行业竞争优势、拓宽绿色市场份额、规避可能的经济风险,而且具有体现企业社会责任感、树立良好品牌形象、提升企业创新能力和核心竞争力等积极作用。在此基础上,梳理了能源密集型、资源密集型和高新技术企业的碳中和战略及模式,总结分析了国内企业实现碳中和承诺的机遇和挑战,为国内企业制定零碳发展战略、实现碳中和目标提出了路径建议。