东南沿海环境变迁与区域可持续发展现场学术研讨会在福建晋江召开

由中国第四纪科学研究会热带亚热带专业委员会、福建省晋江市人民政府和中科院广州地化所等单位发起和承办的“东南沿海环境变迁与区域可持续发展现场学术研讨会”于2008年5月8日至10日在福建省晋江市召开,来自全国科研院所、高等院校有关专家学者和科技工作者100多人到会。会议收到论文50篇,中科院李坪院士到会并作了有关地质构造和地震问题的学术报告。     

Progress in the study on the formation of the summertime subtropical anticyclone

The studies in China on the formation of the summertime subtropical anticyclone on the climate timescale are reviewed. New insights in resent studies are introduced. It is stressed that either in the free atmosphere or in the planetary boundary, the descending arm of the Hadley cell cannot be considered as a mechanism for the formation of the subtropical anticyclone. Then the theories of thermal adaptation of the atmosphere to external thermal forcing and the potential vorticity forcing are developed to understand the formation of the subtropical anticyclone in the three-dimensional domain. Numerical experiments are designed to verify these theories. Results show that in the boreal summer, the formation of the strong South Asian High in the upper troposphere and the subtropical anticyclone over the western Pacific in the middle and lower troposphere is, to a great extent, due to the convective latent heating associated with the Asian monsoon, but affected by orography and the surface sensible heating over the continents.On the other hand, the formation of the subtropical anticyclone at the surface over the northern Pacific and in the upper troposphere over North America is mainly due to the strong surface sensible heating over North America, but affected by radiation cooling over the eastern North Pacific. Moreover, in the real atmosphere such individual thermal forcing is well organized. By considering the different diabatic heating in synthesis, a quadruple heating pattern is found over each subtropical continent and its adjacent oceans in summer. A distinct circulation pattern accompanies this heating pattern. The global summer subtropical heating and circulation may be viewed as “mosaics” of such quadruplet heating and circulationpatterns respectively. At last, some important issues for further research in understanding and predicting the variations of the subtropical anticyclone are raised.     

《荒漠化与防治教程》书评

正我国是荒漠化最严重的国家之一,荒漠化严重制约着我国相关地区的经济和社会发展,加强对荒漠化的研究和治理十分重要。我国科技工作者对荒漠化与防治开展了很多研究,出版了许多荒漠化及荒漠化防治的专著,但关于荒漠化与防治方面的教材尚少。到目前为止,出版的少数相关教材一般是荒漠化防治工程学和水土保持工程学方面的,缺少关于全面、系统的荒漠化发生理论与治理技术相结合的教材。由陕西师范大学赵景波、罗小庆和邵天杰主编的、中国环境出版社2014年出版的《荒漠化与防治教程》弥补了我国荒漠化与防治教材的空缺。     

沉积物再悬浮对食浮游动物鱼类捕食浮游动物的影响

在亚热带浅水湖泊中,由风浪引起沉积物再悬浮是其重要特征之一.沉积物再悬浮一方面直接影响浮游动物群落结构,另一方面通过影响食浮游动物鱼类对浮游动物的捕食而产生间接影响.以食浮游动物鱼类——餐条(Hemiculter leucisculus)为实验对象,通过模拟实验,比较不同再悬浮条件下餐条对浮游动物群落结构的影响.结果显示,在有餐条的处理组中,大型枝角类短钝溞(Daphnia obtusa)只在弱再悬浮条件下出现,并成为枝角类群落的优势种;在无餐条的处理组中,短钝溞生物量随再悬浮强度减弱而增加.强再悬浮(无餐条)和无再悬浮(有餐条)条件下,小型枝角类角突网纹溞(Ceriodaphnia cornuta)和盘肠溞(Chydorus sp.)为优势种.无论有、无餐条条件下,桡足类优势种均为中剑水蚤(Mesocyclops sp.),其生物量随再悬浮强度减弱而增加.所有处理组中,轮虫丰度均低于枝角类和桡足类丰度.研究表明,在亚热带浅水湖泊中,适当的悬浮质浓度既能干扰食浮游动物鱼类对大型浮游动物的捕食,又不影响大型浮游动物的生存,使得它们保持一定的丰度,通过对浮游植物的摄食,降低叶绿素a浓度.     

难忘的大槽湾

距我的老家村庄北面约3公里的地方,有两座对立的山峰,两山之间是一条缓平、宽阔的大槽,由于湾度相当大,状似农家砍猪菜的砍槽,自古以来人们都称这里为大槽湾。大槽湾地处亚热带季风气候,因日照时间长,气候温和,所以无论种什么庄稼都长势良好,早熟早收。     

关中地区全新世大暖期的土壤与气侯变迁

资料表明，关中地区全新世大暖期土壤中的CaCO3受到了明显淋溶，部分土壤的CaCO3淀积层脱离了粘化层，发育了淋溶性土壤所特有的风化淋滤母质层；该层土壤发生了明显的化学粘化作用，并有Fe2O3和Al20，形成以及亚热带土壤所具有的淀积型红色光性粘土胶膜发育；粘土胶膜含量明显大于淋溶褐土而与黄棕壤接近。由此得出，全新世中期成壤作用比现今显著强，土壤应为发育弱的黄棕壤，当时气候比今明显暖湿；在全新世中期，来自东南的夏季降水气团能够较频繁地到达该区，秦岭已失去温带与亚热带气候分界线的作用，其南北两侧均为亚热带气候。     

中国热带、亚热带西部丘陵山区农业气候资源及合理利用研究

在剖面考察和细网格推算资料分析基础上,系统阐述了西部山区热、水、光等衣业气候资源及农业气象灾害的垂直与水平分布特征,并结合地方生产建设实际,论证了农业气候资源优势及开发利用途径。     

Simulation and Analysis about the Effects of Geopotential Height Anomaly in Tropical and Subtropical Region on Droughts or Floods in the Yangtze River Valley and North China

Previous study comes to the conclusion:based on the anomalies of the South Asian high (SAH),100-hPa geopotential height,and 100-hPa circulation over tropical and subtropical regions,we can predict precipita- tion anomaly in the Yangtze River Valley and North China.To test its validity,a series of experiments have been designed and operated,which include controlled experiment,sensitivity experiment (which has added anomalies into 100-hPa geopotential height and wind field),and four-composite experiments.Experiments based on the composed initial field such as EPR-CF,EPR-CD,EPR-HF,and EPR-HD,can reproduce the floods or droughts in the Yangtze River Valley and North China.It suggests that anomalies of the SAH,100- hPa geopotential height,and circulation over tropical and subtropical regions may probably imply summer precipitation anomalies in the two regions.Sensitivity experiment results show that anomalies of the SAH, 100-hPa geopotential height,and southwest flow in the previous period is a signal of droughts or floods for the following summer in the Yangtze River Valley and North China.And it is also one of the factors that have impact on summer precipitation anomaly in the two regions.Positive anomaly of 100-hPa geopotential height and the anomalous intensifying of the SAH and southwest flow will induce floods in the Yangtze River Valley and droughts in North China;while negative anomaly of 100-hPa geopotential height and anomalous weakening of the SAH and southwest flow will induce droughts in the Yangtze River Valley and floods in North China.     

A Synoptic Snapshot of the East Cape Eddy （ECE）

1Introduction The East Australian Current(EAC)partially sepa-rates from the coast of Australia(Godfrey et al.,1980)and subsequently flows eastward along the Tas-man Front(TF)(Warren,1970).When the east-ward flow reaches the northernmost point of New Zealand,it turns southeastward and becomes the East Auckland Current(EAUC).The flow that goesround the East Cape is named the Ease Cape Current(ECC).The ECC separates from North Island and proceeds eastward to the north of the Chatha…