重庆三峡广场商圈大气CO2浓度变化特征与相关因素分析

利用便捷式CO2温度监测仪监测了重庆三峡广场商圈不同地点和时间的大气CO2浓度,采用摄像机记录车流量、人流量及天气状况,采用单因素方差分析和Pearson相关性检验法分析了城市商圈大气CO2浓度时空变化特征及其与各影响因素的相关关系。研究表明,车流量和天气状况是影响城市商圈大气CO2浓度的重要因素,人流量对城市商圈大气CO2浓度的影响不明显。     

SO_2和NO_2对高梁生长的影响及感受性

引言目前人们已把SO_2和NO_2对作物的许多影响完整地记录下来。有些研究者指出,很低浓度的SO_2就能有效地降低某些重要的经济作物的生理过程和产量。不过,降低农作物产量的临界浓度很可能得取决于环境的变异。烟薰法实验系统的差别引起了获得结果的许多差异。作物对SO_2的感受性与温度和     

柳叶蜡梅苗定植后光合作用日变化初探

应用光合作用分析仪对定植于花盆和山坡地两种不同生长环境下柳叶蜡梅苗的光合作用效率进行分析.结果表明,两种定植条件下的柳叶蜡梅苗都有“光合午休”现象,但净光合速率日变化曲线不同；盆栽苗蒸腾速率变化呈单峰曲线,与其净光合速率变化不一致；山地苗蒸腾速率与净光合速率的变化趋势基本一致；盆栽苗进气CO2浓度在一天中变化幅度不大,较高浓度在早晨；山地移植苗进气CO2浓度中午为低谷,下午15:30之后浓度较高.定植苗的光合有效辐射值、叶表面温度、进气CO2浓度的增加等生理生态因子对净光合速率存在不同程度的影响.     

基于走航的CO2驱油与封存场地大气环境监测

CO2驱油和地质封存项目中的泄漏风险是制约其发展的重要瓶颈,对地表大气中的CO2开展监控被认为是预防项目泄漏风险、证实项目埋碳量的关键手段。该研究首次引入了CO2走航监测技术,选取新疆克拉玛依油田CO2混相驱试验区为研究对象,开展了地表CO2泄漏特征监测。监测结果显示：该试验区周边行政区内9个功能区块的CO2均值浓度为417.95×10-6～767.59×10-6,清洁本底浓度为416.66×10-6。试验区CO2小时浓度变化与现场生产组织的作息呈现相关性,小时均值浓度为416.81×10-6～420.69×10-6,与本底浓度差异不大,因此对大气环境影响较小。局部异常点出现于注气点、采油井、现场休息室、修井作业点、生活基地5类位置。注气系统中,储罐、换热器和注入泵有较明显检出,6组注气系统的泄漏值最大值低于CO2长期接触限值,远低于CO2短期接触限值。     

乌鲁木齐市采暖期居室内空气污染状况及其来源

1989年采暖期对乌鲁木齐市居室内 CO、SO_2、NO_X 和 TSP 浓度,以及吸烟对 CO 浓度影响进行了实际采样分析,并对污染物来源和变化规律作了初步探讨。     

秦皇岛空气污染特征及其与气象因素的关系

利用国控站点空气监测数据和气象数据,对2016年秦皇岛市空气污染特征及其与气象因素的关系进行了分析。结果表明:2016年秦皇岛市NO_2、PM_(10)和PM_(2.5)浓度未达到国家二级标准限值,污染物浓度季节变化规律明显,SO_2峰值出现在1月,O_3峰值出现在5月,PM_(10)、PM_(2.5)、NO_2和CO浓度峰值均出现在12月。污染物在西南偏西风时污染程度较高。PM_(10)、PM_(2.5)、SO_2、CO浓度受风速影响较小,NO_2、O_3浓度受风速影响较大。颗粒物浓度受湿度影响较大,随湿度增加而增大。     

不同有机物料还田对土壤结构与玉米光合速率的影响

为解决由于长期不合理耕作及有机物料利用率低而导致土壤养分贫瘠和土壤物理性状恶化情况,本试验针对黑土宜板结和肥力保持等问题设置了不同技术措施,研究在玉米生育时期不同有机物料还田模式对土壤结构特性及玉米光合速率的影响。结果表明：收获后浅翻深松＋秸秆还田和有机肥处理较常规处理,土壤容重下降了0.13 g＆#183;cm-3和0.09 g＆#183;cm-3,浅翻深松＋秸秆还田、有机肥、翻压绿肥和生物肥均能降低土壤紧实度,改善土壤三相比,增加土壤通气透水性,使得土壤物理结构得到改善。有机肥、秸秆还田和生物肥处理提高玉米喇叭口期光合速率,较常规处理提高2.1～7.6μmol＆#183;m-2＆#183;s-1;秸秆还田和生物肥较常规施肥处理,蒸腾速率下降57%和56%;在玉米喇叭口期各处理气孔导度均小于对照,灌浆期秸秆还田处理较常规处理气孔导度增加,导致叶片胞间CO2浓度下降,说明气孔阻力的降低导致叶片胞间CO2浓度降低。有机物料还田后可以降低土壤容重、紧实度,土壤三项比达到合理范围,并且可以提高作物的光合速率,降低蒸腾速率,尤其是秸秆还田和有机肥处理好于其他处理。保护性耕作和有机物料还田对于提高土壤肥力、改善土壤物理特性,提高作物光合速率,增加作物产量均起到积极促进作用。     

作物受二氧化硫危害的原理

一、作物的暗呼吸和二氧化硫在二氧化硫对作物的光合作用和呼吸所造成的影响中,对光合作用的影响显著,这方面的研究也很多,但是对光呼吸或暗呼吸而带来的影响,几乎没有研究。水稻幼株的暗呼吸和二氧化硫浓度之关系见图1。随着SO_2浓度的增加,对水稻幼株的危害几乎呈直线加剧。SO_2为4 ppm时,暗呼吸暂时加强,但随着时间的延长,危害作用明     

湿地匍灯藓监测大气污染的初步研究

本研究监测了湖南省某市5个点位2个时段的大气SO_2、NO_2、CO、PM_(2.5)污染实况,同期检测了自然暴露的湿地匍灯藓的Chlo、MDA、Pro水平。监测和检测结果显示,PM_(2.5)是影响空气质量的主要因子,Pro是比Chlo、MDA更灵敏的监测指标;相关系数分析显示,PM_(2.5)与湿地匍灯藓之间的污染物浓度—生理指标水平关系具有更高的相关性。本研究认为,湿地匍灯藓Pro可应用于PM_(2.5)污染的短期追溯性监测和现状监测。     

长沙城区大气中二氧化碳浓度变化及与其它污染物相关性分析

利用长沙市城区2011年及2012年连续自动监测获得的CO2数据,两年的平均值为412．2×10^-6,高于世界本底站青海瓦里关5．6％,与临安、无锡相当,略高于乌鲁木齐,而低于北京、上海。冬季CO2浓度日小时变化呈现双峰形态,峰值出现在上午9时及晚上19时～21时。夏季日小时变化为单峰形态,峰值出现在上午8时。冬季CO2浓度日均值为420．3×10^-6,比夏季高3．4％。CO2除与O3呈负相关以外,与其它污染物均呈现显著性正相关,特别是与CO、NO、NO2、NOx、SO2的相关性最强,而与颗粒物（PM10、PM25）的相关性稍差。     

温室效应与全球变化（三）：全球碳循环与人为二氧化碳排放的控制

本文综述了全球碳循环的现状及人类活动对它的影响，指出人为释放大量的二氧化碳又不使大气中二氧化碳浓度升高是不可能的，人为促进海洋光合作用的增加和在陆地上植树造林在控制大气二氧化碳浓度上升上所能起的作用也是有限的。只有在不放慢经济发展的速度，不降低能源总有效消费量的情况下，努力减少人为二氧化碳的排放才是现实的。本文探讨了这一途径在技术上的可能性。     

温室效应与全球变化（四）：通过国际谈判与合作减少全球人为二氧化碳的排放

在限制人为二氧化碳的排放以控制全球变化的问题上，发达国家与发展中国家之间存在着尖锐的利益冲突。目前，大气中人为增加的二氧化碳绝大中份是发达国家在过去１５０年内排放的。它们目前的排放量仍占全球人为排放量的四分之三。发展中国家在经济发展过程中不可避免地要增加二氧化碳的排放量，这是它们正当的发展权利。作者讨论了各种限制人为二氧化碳排放的国际协定方案，认为可交易的二氧化碳排放许可证制度是比较现实的方案。     

SO_2气敏电极的研制及扩大应用

本文用自制二甲基硅橡胶作为气透膜制成一种SO_2气敏电报,电极的线性响应范围与内充电解质NaHSO_3的浓度有关。CO_2气敏电极可以用SO_2气敏电极骨架将NaHSO_3内充电解质改为NaHCO_3制成。     

Potential Economic Benefits of Adapting Agricultural Production Systems to Future Climate Change

Potential economic impacts of future climate change on crop enterprise net returns and annual net farm income (NFI) are evaluated for small and large representative farms in Flathead Valley in Northwest Montana. Crop enterprise net returns and NFI in an historical climate period (1960–2005) and future climate period (2006–2050) are compared when agricultural production systems (APSs) are adapted to future climate change. Climate conditions in the future climate period are based on the A1B, B1, and A2 CO₂ emission scenarios from the Intergovernmental Panel on Climate Change Fourth Assessment Report. Steps in the evaluation include: (1) specifying crop enterprises and APSs (i.e., combinations of crop enterprises) in consultation with locals producers; (2) simulating crop yields for two soils, crop prices, crop enterprises costs, and NFIs for APSs; (3) determining the dominant APS in the historical and future climate periods in terms of NFI; and (4) determining whether NFI for the dominant APS in the historical climate period is superior to NFI for the dominant APS in the future climate period. Crop yields are simulated using the Environmental/Policy Integrated Climate (EPIC) model and dominance comparisons for NFI are based on the stochastic efficiency with respect to a function (SERF) criterion. Probability distributions that best fit the EPIC-simulated crop yields are used to simulate 100 values for crop yields for the two soils in the historical and future climate periods. Best-fitting probability distributions for historical inflation-adjusted crop prices and specified triangular probability distributions for crop enterprise costs are used to simulate 100 values for crop prices and crop enterprise costs. Averaged over all crop enterprises, farm sizes, and soil types, simulated net return per ha averaged over all crop enterprises decreased 24% and simulated mean NFI for APSs decreased 57% between the historical and future climate periods. Although adapting APSs to future climate change is advantageous (i.e., NFI with adaptation is superior to NFI without adaptation based on SERF), in six of the nine cases in which adaptation is advantageous, NFI with adaptation in the future climate period is inferior to NFI in the historical climate period. Therefore, adaptation of APSs to future climate change in Flathead Valley is insufficient to offset the adverse impacts on NFI of such change.     

秦皇岛市陆地植被与大气碳平衡研究

地球的碳循环已成为全球气候变化的一个热点,陆地植被是地球破循环中的一个重要贮存库。本文在分析秦皇岛市陆地植被状况的基础上,对CO_2排放量和吸收量进行了估算,结果表明,陆地植被吸收CO_2的数量占排放量的79％。结合秦皇岛市的实际,提出有利于大气碳平衡的对策。     

Methane oxidation in an intensively cropped tropical rice field soil under long-term application of organic and mineral fertilizers

Methane (CH4) oxidation is the only known biological sink process for mitigating atmospheric and terrestrial emissions of CH4, a major greenhouse gas. Methane oxidation in an alluvial soil planted to rice (Oryza sativa L.) under long-term application of organic (compost with a C/N ratio of 21.71), and mineral fertilizers was measured in a field-cum-laboratory incubation study. Oxidation rates were quantified in terms of decrease in the concentration of CH4 in the headspace of incubation vessels and expressed as half-life (t(1)2) values. Methane oxidation rates significantly differed among the treatments and growth stages of the rice crop. Methane oxidation rates were high at the maximum tillering and maturity stages, whereas they were low at grain-filling stage. Methane oxidation was low (t(1)2) = 15.76 d) when provided with low concentration of CH4. On the contrary, high concentration of CH4 resulted in faster oxidation (t(1)2) = 6.67 d), suggesting the predominance of "low affinity oxidation" in rice fields. Methane oxidation was stimulated following the application of mineral fertilizers or compost implicating nutrient limitation as one of the factors affecting the process. Combined application of compost and mineral fertilizer, however, inhibited CH4 oxidation probably due to N immobilization by the added compost. The positive effect of mineral fertilizer on CH4 oxidation rate was evident only at high CH4 concentration (t(1)2 = 4.80 d), while at low CH4 concentration their was considerable suppression (t(1) = 17.60 d). Further research may reveal that long-term application of fertilizers, organic or inorganic, may not inhibit CH4 oxidation.     

含硫气田设备及管道的腐蚀与防腐

四川气田系我国典型的含硫气田,设备及管道的腐蚀与防腐问题一直是一个重要的研究课题。文章首先分别探讨了H_2S腐蚀和CO_2腐蚀的机理及其影响因素,进而提出了H_2S和CO_2的防腐工艺和措施,最后探讨了含硫气田腐蚀及防腐研究的热点和发展方向,指出应该大力开展高含硫气田的腐蚀和防腐技术、二氧化碳条件下的钢材腐蚀机理和防腐技术、细菌腐蚀以及新型合金材料及非金属管道的应用研究,同时进行防腐实验。     

Food safety assessment of planting patterns of four vegetable-type crops grown in soil contaminated by electronic waste activities

A field experiment was conducted to assess the effect of crop and planting pattern on levels of cadmium (Cd), lead (Pb), and copper (Cu) in crops grown in soil contaminated by electronic waste. The crops were maize (Zea mays L. var. Shentian-1), tomato (Solanum lycopersicum L. var. Zhongshu-4), cabbage (Brassica oleracea L. var. Jingfeng-1), and pakchoi (Brassica chinensis (L.) Makino. var. Youdonger-Hangzhou). The planting patterns were crop monoculture, crop co-planted with a legume, and crop co-planted with another crop. Metal concentrations in the edible parts of the crops varied with types of metals and crops. Pb concentration was higher in leafy vegetables (cabbage and pakchoi) than in maize or tomato, Cd concentration was higher in tomato and pakchoi than in maize or cabbage, and Cu concentration was higher in maize and pakchoi than in tomato or cabbage. Metal concentrations in the edible part were also influenced by planting pattern. Relative to monoculture, co-planting and especially co-planting with Japanese clover tended to decrease Pb accumulation and increase Cd accumulation. According to the maximum permissible concentration (MPC) standard of the National Standard Agency in China, only maize (under all planting patterns) could be safely consumed. Because co-planting tended to increase Cd accumulation even in maize, however, the results suggest that maize monoculture is the optimal crop and planting pattern for this kind of contaminated soil.     

土壤水分管理对甲烷和氧化亚氮排放的影响

为控制农田温室气体排放的途径提供依据,通过实验室培养的方法测定了不同水分管理条件下CH4和N2O的排放,干旱处理（60％-70％WFP）和长期淹水土样在施肥后的Eh变化。最终得出：稻田CH4和N2O排放之间存在着互为消长的关系（R2=0．609）,CH4和N2O的排放是水肥共同作用的结果,水分管理通过Eh来影响气体排放,有机质是造成前后期排放浓度差异的主要原因。