1979年以来南黄海辐射沙洲潮滩脊线时空变化研究

基于遥感和GIS技术,提取了南黄海辐射沙洲1979年、1990年、2002年和2014年4个时期的潮滩脊线,并对时空变化特征进行系统分析。研究显示：① 辐射沙洲潮滩脊线可分为主线和支线2级,滩脊主线为条子泥-高泥-东沙潮滩脊线,支线为滩脊主线两侧分支;② 辐射沙洲潮滩脊线空间组合形态总体稳定,条子泥段滩脊主线总体呈东西向,东沙段滩脊主线总体呈南北向,高泥段滩脊主线连接条子泥和东沙;③ 滩脊线演变呈显著空间分异,条子泥段滩脊主线南向迁移显著,东沙段和高泥段滩脊主线总体向东迁移,迁移距离条子泥段滩脊主线>高泥段、东沙段,条子泥段滩脊主线中部>两侧、东沙段滩脊主线北段>南段,条子泥滩脊支线形态和位置变化均较东沙滩脊支线显著。     

亚热带马尼拉草坪生态系统CO2净交换量测定方法比较

利用IRGA法和GC法,同步观测了3种天气(晴天、多云、阴天)条件下福州市江滨公园马尼拉草坪生态系统CO2净交换量(NEE)的白昼动态变化,比较IRGA法和GC法透明通量箱对观测样点环境的影响程度,并探讨其对NEE观测结果的影响.结果表明:在单次观测结束时,IRGA法通量箱对样点环境的扰动小于GC法,晴天白天二者箱内的平均升温分别为179 ℃和233 ℃,箱内平均光合有效辐射(PAR)降低幅度分别为1100%和2100%.3种天气情况下,IRGA法与GC法观测的NEE白天变化趋势较一致,但3种天气相同时段内GC法测定的NEE平均值比IRGA法高317 μmol·m-2·s–1,二者的差异在中午最大,在清晨和傍晚较小.IRGA法比GC法可以更为准确地测量草坪NEE.     

能源合理利用与CO2减排的国际经验及其对我国的启示

减少温室气体排放,以减缓和控制气候变化,是《联合国气候变化框架公约》和《京都议定书》的主要目标。美英法德日等主要发达国家,在工业化道路上,已走过数百年的历程,积累了包括能源节约和CO₂减排在内的先进技术和丰富经验。为了减少CO₂排放,实现可持续发展,必须借鉴国外在能源利用、结构调整和节能方面的经验。可供我国借鉴的国外经验主要有：(1)制订和实施能源合理利用与减少CO₂排放的发展战略;(2)建立和健全法律;(3)调整能源结构;(4)运用经济激励的政策和手段。     

白草和赖草无性系生长对干旱胁迫的反应

研究桶栽条件下干旱胁迫对白草和赖草无性系生物影响的结果表明:干旱胁迫对白草和赖草无性系的生长均具有抑制作用,但同一胁迫强度所导致的抑制程度因植物种类的不同而各有差异。在形态方面,白草的根茎总长度和总芽数大于赖草,而节间长度则小于赖草,产生的分株数目也比赖草多;在生物量的分配上,白草比赖草对地下部分的投资更多,须根所占的比例更大。白草无性系因具这些可塑性变化而比赖草对干旱胁迫更具适应性。     

阿司匹林的合成条件研究

以水杨酸和醋酐为原料经O-酰化反应合成阿司匹林，比较了三氯化铝、三氯化铋和无水碳酸钠三种不同催化剂以及反应条件对合成的影响，找到了最佳催化剂和最佳反应务件，即以三氯化铝为催化剂，其用量为水杨酸的2％，水杨酸与醋酐的摩尔比为1：2，反应时间为30min，回流温度为85℃左右，阿司匹林产率可迭72．6％。实验表明该催化剂催化效果好．不污染环境，是一种环境友好的催化剂。同时，本法简单、快速、经济、无污染，产品质量好，适于工业化生产。     

Geochemical Characteristics of Particulate Organic Carbon in the Kocebu Seamount Waters of the Western Pacific Ocean in Spring 2018

The study of the geochemical characteristics of the POC in the seamount area will be of great significance for further understanding the material cycle process in the seamount ecosystem. Based on a comprehensive survey of the Kocebu seamount in the Western Pacific Ocean in March, 2018, the distribution, source and composition of Particulate Organic Carbon (POC) in the seawater of the Kocebu seamount area were discussed. The results showed that the concentration of POC in the Kocebu seamount area gradually decreased with the increasing water depth, and slightly rose in the water layers near the bottom of the seamount. The average concentration of POC in each water mass was sorted from high to low in the order of North Pacific Tropic Water, North Pacific Intermediate Water and Deep Water (DW), and the concentration of POC at stations near the seamount summit was lower than that far from the seamount in the DW. There was upwelling at the water layers of 750~1 500 m above the seamount summit, causing the uplift of the 12.50 μg/L POC isoline in this region, however, no “seamount effect” was formed. The POC was mainly imported from the sea with an average POC/PON of 3.75. At the water layers of 0~300 m, only the POC/chlorophyll a (Chl a) at deep chlorophyll maximum layer was less than 200, indicating that the POC in this region was mainly in a form of life, while at the water layer of 300 m, the POC/Chl a increased sharply, indicating that the non-living POC contributed the most to the total POC.     

深埋隧洞力学响应监测与测试设计的思考

深埋隧洞工程越来越多,但相关工程经验积累不足,设计和计算方法远未成熟,深埋隧洞工程设计和施工安全控制需要大量现场监测和测试数据的支撑,而现有的监测和测试设计方法均针对浅埋工程的特点提出,在深埋隧洞施工过程中应用时遭遇到极大挑战。为此,首先依据现场揭露现象和多种先进观测技术获得的成果,分析了深埋硬岩隧洞施工期围岩的开挖力学响应特征和运行期衬砌的力学响应特征,剖析了现今主流观测方法存在的问题,提出了6条关于深埋隧洞典型断面监测和测试设计的建议,为促进此类工程相关设计方法的完善提供参考。     

未来气候变化背景下我国橡胶树寒害事件的变化特征

利用1981—2010年历史气象数据和2031—2060年（RCP2.6和RCP8.5）气候情景数据,根据橡胶寒害等级指标,结合插值分析、提取分析和地图代数等空间分析方法,研究在未来气候情景下我国橡胶树寒害事件的变化特征。结果表明：(1) RCP2.6和RCP8.5气候情景下2031—2060年我国橡胶种植适宜区基本呈现寒害发生降低的趋势,其中次适宜区（III）和局部可植区（IV）的降低幅度较为明显,有向高一等级适宜区转化的趋势。(2)我国橡胶树寒害中心的纬度,由1981—2010年的22.5°~23.5°N向北移动至2031—2060年RCP2.6情景下的24.0°~24.5°N和RCP8.5情景下的23.5°~24.0°N。(3) 2种气候情景下,2031—2060年我国海南、广西、广东、福建等植胶区橡胶树寒害发生概率（较基准时段1981—2010年）主要呈现降低趋势,云南植胶区在2种气候情景下有明显的差异,表现为RCP2.6情景下,轻度和特重寒害呈现降低趋势,中度和重度寒害呈现增加趋势;RCP8.5情景下,轻度和重度寒害呈现降低趋势,中度和特重寒害呈现增加趋势。(4)对比2种气候情景较基准时段的变化情况,RCP2.6情景对橡胶树轻度和特重寒害影响较大,RCP8.5情景对橡胶树中度和重度寒害影响较大。     

Exchange fluxes of VOSCs between rice paddy fields and the atmosphere in the oasis <Emphasis Type="Bold">of arid area</Emphasis> in Xinjiang,China

Investigations about VOSCs (volatile organic sulfur compounds) have been received increasing attention for their significant contribution to the nonvolcanic background sulfate layer in the stratosphere and the earth’s radiation balance and as a potential tool to understand the carbon budget. In this study, COS and CS₂ were always recorded throughout the entire rice cultivation season of 2014. COS fluxes appeared as emission in non-planted soil and as uptake in planted soil, the corresponding results were obtained as 2.66 and ?2.35 pmol·m^?2·s^?1, respectively. For CS₂, both planted and non-planted paddy fields acted as sources with an emission rate of 1.02 pmol·m^?2·s^?1 and 2.40 pmol·m^?2·s^?1, respectively. COS emission or uptake rates showed a distinct seasonal variation, with the highest fluxes at the jointing-booting stage. COS and CS₂ fluxes increased with increasing N fertilizer use because of improved plant and microbial growth and activity. Plots treated with both N and S reduced COS and CS₂ fluxes slightly compared with plots with only-N treatment. Light, soil moisture or temperature showed no significant correlation with COS and CS₂ fluxes, but revealed the important impacts on the magnitude and direction of gases fluxes. The results also showed that the (available) sulfur contents in soil and roots had a certain effect on VOSCs emission or uptake. Our results highlight the significance of biotic and abiotic production and consumption processes existing in the soil.