不同稻麦种植模式适应气候变化的效益比较分析

通过调查江苏省全球环境基金项目区农户和专家的投入产出,使用成本效益分析方法和IPCC推荐的温室气体估算方法评估比较了3种种植方式（人工插秧、机械插秧和直播）的水稻在麦稻轮作复种“两晚”模式（水稻晚收, 小麦晚播）下的社会、经济和生态效益。结果表明：水稻直播和机械插秧可以节省更多劳动力;农业机械燃油、施用化肥、稻田淹水等农作措施导致了大量人为温室气体排放;水稻种植方式为人工插秧的麦稻轮作模式能取得最优的经济和生态效益;“两晚”模式实施的关键是适时地利用近年来增加的农业气候资源。水稻人工插秧与麦稻“两晚”相配合的种植模式是减缓和适应气候变化的较优选择。     

Monitoring winter wheat growth in North China by combining a crop model and remote sensing data

Both of crop growth simulation models and remote sensing method have a high potential in crop growth monitoring and yield prediction. However, crop models have limitations in regional application and remote sensing in describing the growth process. Therefore, many researchers try to combine those two approaches for estimating the regional crop yields. In this paper, the WOFOST model was adjusted and regionalized for winter wheat in North China and coupled through the LAI to the SAIL–PROSPECT model in order to simulate soil adjusted vegetation index (SAVI). Using the optimization software (FSEOPT), the crop model was then re-initialized by minimizing the differences between simulated and synthesized SAVI from remote sensing data to monitor winter wheat growth at the potential production level. Initial conditions, which strongly impact phenological development and growth, and which are hardly known at the regional scale (such as emergence date or biomass at turn-green stage), were chosen to be re-initialized. It was shown that re-initializing emergence date by using remote sensing data brought simulated anthesis and maturity date closer to measured values than without remote sensing data. Also the re-initialization of regional biomass weight at turn-green stage led that the spatial distribution of simulated weight of storage organ was more consistent to official yields. This approach has some potential to aid in scaling local simulation of crop phenological development and growth to the regional scale but requires further validation.     

西北太平洋台风累积动能的气候特征

利用1945-2008年JTWC提供的台风资料,计算了西北太平洋地区台风累积动能,分析了台风累积动能的时间分布特征,统计累积动能与尼诺3.4区海温的关系.结果表明:每年台风累积动能主要集中在6-12月;累积动能有明显的阶段性;1990年以后极端台风事件发生频数有增加的趋势;6-12月台风累积动能与尼诺 3.4区的海温距平呈正相关;台风累积动能与海温的关系通过沃克环流和局地哈得来环流起作用.     

江淮梅雨期降水南北反位相分布与大气准双周振荡

利用1954—2005年中国740站逐日降水资料和NCEP/NCAR再分析资料,分析江淮梅雨期降水的南北反位相分布(Anti-Phase Distribution:APD)和大气准双周振荡(Qusi-Biweekly Oscillation:QBWO)之间的关系,诊断结果表明:(1)1954—2005年江淮梅雨APD共有16年较为显著。从1990年代开始,梅雨APD显著增强,并且表现出显著的2年和4～6年振荡周期。在降水较多的区域,降水的准双周振荡往往也较强。(2)梅雨期降水APD和中国东部地区降水的南北变动同属一个位相,中国东部地区的南涝北旱或者南旱北涝在很大程度上可以由江淮地区降水的分布类型来说明。(3)"南旱北涝"年,准双周滤波的整层水汽通量能够传播到30°N以北,同时存在强烈的水汽通量辐合从中高纬度向南传播到江淮流域。而在"南涝北旱"年,准双周的水汽输送所能到达的纬度明显偏南,来自中高纬度向南传播的水汽通量辐合也不显著。(4)"南旱北涝"年降水正位相,西北太平洋副热带高压(简称西太副高)脊线位于22°N以北,850 hPa低频反气旋的位置相对于"南涝北旱"年偏北,调节西太副高进入南海位置也偏北。南海和江淮上空的准双周垂直速度异常位置整体偏北,第3位相的上升运动和第7位相的下沉运动都位于30°N以北,南海的垂直速度异常也主要位于南海北部,而在"南涝北旱"年,准双周垂直速度异常的分布偏南。     

山区水稻后期气象灾害与发展粳稻的可行性

根据籼、粳稻抽穗开花期要求的气象条件,分析了当地该阶段常年气象资料,结果发现:此期低温频繁、降温快,籼稻遇冷害减产几率60%以上;由于粳稻耐寒.要求气温指标较籼稻低2℃以上,遇冷害减产几率0%～3%.因此.南召县缩籼扩粳对高产稳产,改善民生.提高效益,都具重要意义.     

The sources and seasonal variations of organic compounds in PM<Subscript>2.5</Subscript> in Beijing and Shanghai

Fine aerosol samples were collected throughout spring, summer, and winter in 2004∼2005 at a major urban traffic junction (BNU) and a suburban location (MY) in Beijing and at a downtown site (SH) in Shanghai, China. Ten of the 16 EPA priority polycyclic aromatic hydrocarbons (PAHs), seven fatty acids, levoglucosan, and cholesterol were identified and quantified. PAHs detected in Beijing and Shanghai were up to one order of magnitude higher than those reported in the developed countries either in urban or suburban areas, while levoglucosan was one order of magnitude lower than that in other countries for no biomass combustion in domestic heating in the mega-cities in China. PAHs showed the same seasonal trend in all sampling sites as the highest in winter and the lowest in summer, while fatty acids no pronounced seasonal variation. A significant fraction of levoglucosan from cooking with higher concentrations in urban than in suburban area contributed to the ambient atmosphere, indicating that the main source of levoglucosan in urban environment would be cooking rather than biomass burning. The relative contributions of coal combustion and vehicle exhaust sources to PAHs in fine aerosols were preliminarily estimated to be 1:2 in Beijing and 1:1 in Shanghai, revealing that the air pollution in these mega-cities in China was mainly the mixing of coal combustion with vehicle exhaust. Cooking was one of the major sources of organic aerosols in both Beijing and Shanghai.     

GRAPeS三维变分同化系统的理想试验

文中介绍了一种新的、适合格点模式的三维变分同化方案GRAPeS 3DVAR。该方案采用相互独立的流函数、非平衡速度势函数、非平衡位势和水汽作为分析变量。通过变量变换对目标函数进行预调节 ,不仅避免了直接计算背景误差协方差逆矩阵的困难 ,而且改善了Hessian矩阵的性状 ,提高了收敛速度。采用EOF分解方法 ,将三维分析变量投影到垂直摸态上 ,分解成为二维场 ;水平方向采用数字 (递归 )滤波器代替矩阵运算 ,实现和简化了方案的求解。此外 ,还考虑了质量场和风场之间的平衡约束关系。理想试验结果表明 ,GRAPeS 3DVAR能够正确地反映多变量之间相互作用关系 ,收敛迅速 ,分析结果合理     

纤维矿物生物活性研究的新进展

石棉、毛沸石、硅灰石、坡缕石、海泡石、水镁石是被国际癌症研究所（ＩＡＲＣ）列为具有致癌、潜在致癌作用或具有较强生物活性的六种纤维矿物,本文综述了目前国内外对这几种纤维矿物生物活性的研究状况及最新进展     

近3000cal.aB.P.以来东海东北部环境异常及其与全新世ElNiño活动的可能联系

利用取自东海东北部、冲绳海槽西侧陆坡的重力柱状岩芯DOC082（29°13.93′N,128°08.53′E;水深1128m）,通过对碳酸钙、有机碳和蛋白石等生源组分含量的分析,结合浮游有孔虫、底栖有孔虫、放射虫和硅鞭藻等微体古生物化石丰度的变化以及底栖有孔虫属种组成特征,揭示了全新世东海东北部生物生产力的演变。研究结果显示,近10500cal.aB.P.以来生源组分含量和微体古生物化石丰度的演变趋势十分相似,明显分为3个阶段:约4000cal.aB.P.之前的早、中全新世明显偏低,大约在4000cal.aB.P.左右开始突然大幅度上升,而约3000cal.aB.P.以来的晚全新世以持续的高值为显著特征。生源组分含量、微体古生物化石丰度以及底栖有孔虫内生属种Uvigerina和Bulimina百分含量等指标的变化一致指示,东海东北部近10500cal.aB.P.以来古生产力演变的显著特征是早、中全新世明显偏低,约4000cal.aB.P.左右突然且大幅度上升,大约3000cal.aB.P.之后的晚全新世为生物生产力异常的高值期;同时有研究表明该区域的表层海水年平均温度（SST）也呈现了明显的三段式演变:早全新世10500～8400cal.aB.P.期间为持续的高值期、中全新世SST相对稳定、3100～500cal.aB.P.期间的晚全新世为显著的低SST时期[1]。近3000cal.aB.P.以来古生产力的异常高值和表层海水古温度的大幅度下降说明晚全新世区域海洋环境发生了明显的改变。据东海东北部现代生物生产力和表层海水温度的分布特征和控制机制、结合现代ElNio发生期间中国大陆气候和降水异常以及黑潮暖流变异的分析表明,近3000cal.aB.P.来东海东北部的环境异常可能是对晚全新世ElNio活动显著增强的反应。     

气候模拟数据的订正与应用——以北京为例

为了消除气候模拟数据中气候平均值和气候变率的漂移,发展了一种新的数据订正方案。应用该方案对IPCC提供的B2情景下北京未来100 a气候预估值进行了订正试验,证实了方案的可用性。在此基础上分析了北京未来气候变化特征,结果表明：21世纪北京气温将继续上升,升温速率约为0.31℃/10 a,最低、最高气温的非对称变化仍将持续;未来北京年降水量呈微弱下降趋势,下降速率约为1.03 mm/10 a。