基于CMIP5多模式集合预估东海和南海21世纪海平面高度变化

人类活动引起的当代气候变暖已导致全球海平面显著上升,在21世纪全球气候继续变暖的背景下,东南沿海海平面的升高将对区域环境及社会可持续发展带来巨大挑战,但目前对未来区域海平面变化的预估尚存在较大的不确定性。本文基于筛选的国际耦合模式比较计划第5阶段（CMIP5）的10个模拟性能较好的气候模式输出结果,通过多模式集合预估了未来温室气体三种排放情景下21世纪东海和南海区域海平面高度的趋势变化,并分析了不同影响因子的贡献。通过计算海水热比容、盐比容和动力因子对海平面高度的影响,并在考虑冰川冰盖消融等因子的订正后,发现：21世纪东海和南海海平面高度都呈现连续上升趋势,东海和南海地区上升幅度略小于全球平均,南海上升幅度略大于东海。在温室气体低（RCP2.6）、中（RCP4.5）和高（RCP8.5）排放情景下,21世纪后期（2081—2100年）较前期（2006—2025年）东海/南海平均海平面分别上升0.26 [0.01—0.55] m/0.29 [0.05—0.55] m、0.38 [0.10—0.66] m/0.40 [0.14—0.67] m和0.52[0.15—0.89] m/0.52[0.23—0.83] m（方括号内为相应的不确定性范围）。随着温室气体排放的升高,海平面上升幅度也增大,东海海平面上升区由东南向西北扩展,南海海平面上升区由东北向西南扩展。统计分析还表明：在不同排放情景下,不同影响因子对海平面变化的贡献也不一样,随着排放强度从低到高变化,海洋比容加动力因子的相对贡献从28%—34%升高至46%—47%,而冰川冰盖消融等其他因子的相对贡献从 66%—72%降低至53%—54%。     

塔里木盆地北缘绿洲不同连作年限棉田土壤有机碳、无机碳含量与环境因子的相关性

农田土壤碳库是土壤碳库的重要组成部分,易受人类活动调节且固碳减排潜力巨大,研究土壤有机碳、无机碳含量特征及其与环境因子的关系有助于深入理解土壤生态过程,为全球碳收支平衡研究提供理论支持.本文以塔里木盆地北缘绿洲为靶区,分析土壤碳库特征,结合冗余分析、通径分析,探究土壤有机碳、无机碳含量及其与环境因子的相关关系.结果表明:(1)同一土层不同连作年限棉田土壤有机碳、无机碳含量存在显著差异(P0.05),随连作年限增加,有机碳含量呈先增加后减少趋势,而无机碳含量呈先减少后增加趋势;同一连作年限棉田不同土层土壤有机碳、无机碳含量存在显著差异(P0.05),有机碳含量均在0~20 cm层达到最大值,而无机碳含量均在20~50 cm层达到最大值.(2)通过冗余分析得出环境因子对土壤碳库特征影响的重要性排序为:磷酸酶活性p H值蔗糖酶活性过氧化氢酶活性全氮速效磷速效钾土壤含水量脲酶活性电导率;磷酸酶活性、p H值、蔗糖酶活性、过氧化氢酶活性、全氮、速效磷、速效钾与土壤有机碳、无机碳含量呈极显著相关关系(P0.01);土壤含水量、脲酶活性与土壤有机碳、无机碳含量表现为显著相关(P0.05).(3)通径分析表明,速效钾对有机碳含量直接作用显著,是影响有机碳含量的主要因素,而脲酶活性对无机碳含量直接作用显著,是影响无机碳含量的主要因素.干旱半干旱区土壤有机碳、无机碳含量研究是评价农田生态系统土壤碳的"源/汇"效应的基础数据,对研究全球碳收支平衡和陆地碳循环机制具有重要意义.     

水稻土壤组分去除有机质和游离氧化铁后对As5+吸附解吸特征的影响

采用平衡液吸附法、NaCl解吸剂解吸法研究了名山河流域水稻土原土及各粒径组分去除有机质和游离氧化铁后对砷(As~(5+))的吸附解吸特性,同时运用热力学和动力学方法,研究了去除有机质、游离氧化铁后的土壤微团聚体(0.25~2 mm、0.053~0.25 mm、0.002~0.053 mm、0.002 mm)对砷(As~(5+))的吸附解吸过程。结果表明:1)同时去除有机质和游离氧化铁后,水稻土原土及各粒径组分对砷(As~(5+))的吸附量有所减小,吸附量从大到小依次为(0.002 mm)、0.002~0.053 mm、原土、0.25~2 mm、0.053~0.25 mm。砷(As~(5+))的动力学吸附量随时间延长而逐渐降低,60 min内反应迅速,在600min达到吸附动态平衡,动力学吸附以Elovich方程拟合最佳;2)等温吸附量随砷(As~(5+))的初始质量浓度增加逐渐增加,初始质量浓度0~100 mg/L时反应快速,在砷(As~(5+))初始质量浓度达到160 mg/L时吸附趋于饱和,等温吸附以Freundlich方程拟合最佳;3)易解吸量随时间和浓度的增加而增加,易解吸率顺序与吸附量顺序相反,易解吸率也随着有机质、游离氧化铁含量的减少而增加;4)去除土壤中的有机质、游离氧化铁后,砷的吸附减少量随时间和浓度增加而增加,吸附减少量与有机质、游离氧化铁去除量呈正比。     

衡阳丰乐五号西瓜空心畸形事件调查及气候影响分析

2009年6月衡阳丰乐五号西瓜出现空心、畸形现象,果农经济损失惨重。经相关部门多次调查发现,5月下旬持续低温阴雨天气是造成该事件发生的主要原因,栽培管理不当导致灾损进一步发展。历史数据分析表明,衡阳5月低温天气发生频率为67.57%,主要出现在上旬后期—中旬前期。进入新世纪以后,低温发生频率减少,强度减弱。对西瓜提前栽种似乎更加有利,但由此所带来的风险更大,为了保险起见,应大力推进设施栽培,采用小拱架双膜覆盖等栽培技术。     

High-resolution modeling and evaluation of ozone air quality of Osaka using an MM5-CMAQ system

High-resolution modeling approach is increasingly being considered as a necessary step for improving the monitoring and predictions of regional air quality.This is especially true for highly urbanized region with complex terrain and land-use.This study uses Community Multiscale Air Quality (CMAQ) model coupled with MM5 mesoscale model for a comprehensive analysis to assess the suitability of such high-resolution modeling system in predicting ozone air quality in the complex terrains of Osaka,Japan.The 1-km and 3-km grid domains were nested inside a 9-km domain and the domain with 1-km grid covered the Osaka region.High-resolution Grid Point Value-Mesoscale Model μgPV-MSM) data were used after suitable validation.The simulated ozone concentrations were validated and evaluated using statistical metrics using performance criteria set for ozone.Daily maxima of ozone were found better simulated by the 1-km grid domain than the coarser 9-km and 3-km domains,with the maximum improvement in the mean absolute gross error about 3 ppbv.In addition,1-km grid results fared better than other grids at most of the observation stations that showed noticeable differences in gross error as well as correlation.These results amply justify the use of the integrated high-resolution MM5-CMAQ modeling system in the highly urbanized region,such as the Osaka region,which has complex terrain and land-use.     

Models3在北京地区PM_(10)模拟应用中的三维系统检验

为研究北京地区大气PM10的变化规律和三维空间结构,文章基于Models3/CMAQ空气质量模式,利用北京及周边省市详细调查的污染源数据,采取双层网格嵌套技术建立起适用于北京及周边地区的大气PM10数值模拟系统。为了检验该模式系统的准确性和可靠性,文章将模拟结果与北京市城近郊区7个地面站近2500h的逐时地面监测数据以及一次典型污染过程的激光雷达垂直观测记录分别进行了对比分析,结果表明,该模式系统较好的反映了北京地区PM10浓度三维时空分布特征,是研究华北地区复杂地形下大气PM10传输及演变规律的一个有效工具。     

HP-5毛细管柱气相色谱法分离水中滴滴涕色谱条件研究

本试验利用HP-5毛细管柱,气相色谱法对水中滴滴涕几种衍生体的分离条件进行了研究和优化,找到了最佳仪器条件,为水中滴滴涕的检测提供了一定的试验参考。     

差压法测定水样中的BOD5

差压法（压力感测法）是测定BOD5的一种简单可靠的方法,OxiTop即是基于这一原理的BOD测量系统,经试验验证分析,该方法操作简单、结果准确,是目前测定BOD5较好的一种方法。     

Isolation of marine benzo[a]pyrene-degrading Ochrobactrum sp. BAP5 and proteins characterization

A bacterial strain BAP5 with a relatively high degradation ability of benzo[a]pyrene (BaP) was isolated from marine sediments of Xiamen Western Sea, China and identified as Ochrobactrum sp. according to 16S rRNA gene sequence as well as Biolog microbial identification system. Strain BAP5 could grow in mineral salt medium with 50 mg/L of BaP and degrade about 20% BaP after 30 d of incubation. Ochrobactrum sp. BAP5 was able to utilize other polycyclic aromatic hydrocarbons (PAHs) (such as phenanthrene, pyrene and fluoranthene) as the sole carbon source and energy source, suggesting its potential application in PAHs bioremediation. The profile of total soluble protein from Ochrobactrum sp. BAP5 was also investigated. Some over- and special-expressed proteins of strain BAP5 when incubated with the presence of BaP were detected by two-dimensional polyacrylamide gel electrophoresis, and found to be related with PAHs metabolism, DNA translation, and energy production based on peptide fingerprint analysis through matrix-assisted laser desorption/ionization-time of flight mass spectrometry.     

High-resolution modeling and evaluation of ozone air quality of Osaka using MM5-CMAQ system

High-resolution modeling approach is increasingly being considered as a necessary step for improving the monitoring and predictions of regional air quality. This is especially true for highly urbanized region with complex terrain and land-use. This study uses Community Multiscale Air Quality (CMAQ) model coupled with MM5 mesoscale model for a comprehensive analysis to assess the suitability of such high-resolution modeling system in predicting ozone air quality in the complex terrains of Osaka, Japan. The 1-km and 3-km grid domains were nested inside a 9-km domain and the domain with 1-km grid covered the Osaka region. High-resolution Grid Point Value-Mesoscale Model (GPV-MSM) data were used after suitable validation. The simulated ozone concentrations were validated and evaluated using statistical metrics using performance criteria set for ozone. Daily maxima of ozone were found better simulated by the 1-km grid domain than the coarser 9-km and 3-km domains, with the maximum improvement in the mean absolute gross error about 3 ppbv. In addition, 1-km grid results fared better than other grids at most of the observation stations that showed noticeable di erences in gross error as well as correlation. These results amply justify the use of the integrated high-resolution MM5-CMAQ modeling system in the highly urbanized region, such as the Osaka region, which has complex terrain and land-use.