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1.
香港海域2004年浮游植物群落结构特征   总被引:2,自引:0,他引:2  
根据 2004 年冬、春、夏和秋季对香港海域(东部、中部、西部和南部水域共取 7 个站位)的浮游植物进行采样调查,分析了香港海域浮游植物的种类组成、丰度、优势种、群落组成、多样性和均匀度等群落特征.2004 年香港海域的浮游植物共鉴定了 73 属 196 种(含变种和变型),其中潜在赤潮种 88 种,丰度范围在 9.17 × 103 cells / L ~ 8.56 × 106 cells / L之间,平均值为 9.51 × 105 cells / L.丰度的周年变化曲线呈单峰型,夏季高,秋冬季节低.香港海域的浮游植物种类多样性较高,以暖水性和广分布性种类为主;浮游植物群落与上世纪 70 年代相比,仍以硅藻为主导,但甲藻和微型隐藻的优势有所增加.由于海洋环境特点的不同,香港不同海域的群落组成差异显著.  相似文献   
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Abstract

Waquoit Bay, a shallow bay on Cape Cod, Massachusetts, is exhibiting symptoms of eutrophication, largely attributed to septic nitrogen inputs. This study assessed septic nitrogen inputs by linking a three-dimensional ground-water model, a geographic information system (GIS), and a customized spatio-temporal nitrogen loading program. Owing to the slow speed of ground-water movement, the bulk of septic nitrogen entering the bay lags behind development by nearly a decade. Even if residential development is held at 1989 levels, nitrogen input from septic systems wilt increase by 36% over the current levels. At full residential build-out (i.e., development), septic nitrogen loading will eventually increase to more than twice the current levels.  相似文献   
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This study examined the characteristics of the diurnal variations of heavy rainfall (≥110 mm in 12 hours) in Korea and the related atmospheric circulation for July from 1980?2020. During the analysis period, two dominant pattens of diurnal variation of the heavy rainfall emerged: all-day heavy rainfall (AD) and morning only heavy rainfall (MO) types. For the AD-type, the heavy rainfall is caused by abundant moisture content in conjunction with active convection in the morning (0000?1200, LST; LST = UTC + 9) and the afternoon hours (1200?2400 LST). These systems are related to the enhanced moisture inflow and upward motion induced by the strengthening of the western North Pacific subtropical high and upper-tropospheric jet. For the MO-type, heavy rainfall occurs mostly in the morning hours; the associated atmospheric patterns are similar to the climatology. We find that the atmospheric pattern related to severe heavy rainfalls in 2020 corresponds to a typical AD-type and resembles the 1991 heavy-rainfall system in its overall synoptic/mesoscale circulations. The present results imply that extremely heavy rainfall episodes in Korea during the 2020 summer may occur again in the future associated with the recurring atmospheric phenomenon related to the heavy rainfall.  相似文献   
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Throughout vast areas of Asia, the summer of 2020 was extraordinarily wet. After an exceptionally wet May in North-east India and Bangladesh, excessive rainfall hit at least 10 provinces in central and southern China in June and July, caus-ing extensive flooding in many rural and urban locations. Long standing rainfall, lake and river level records were con-sequently broken in several parts of the region with the Yangtze-Huaihe river valleys, particularly badly impacted, with con-sequential economic losses. Floods and landslides also affected parts of Japan with at least one location in Kumamoto province even experiencing a record-breaking 1000 mm of rainfall in just 3 days in early July. The 2020 wet season in South Korea was also exceptionally long, lasting 54 days, compared to their more usual 32.  相似文献   
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Aerosol is an important component of the atmosphere, and its source, composition, distribution, and effects are highly complicated. Governments and scientists have given much attention to aerosol problems, and it has become a hot topic due to the important role it plays in climate change and the Earth’s environment. In this paper, 1) the importance of aerosol in climate change, the atmospheric environment, and human health is summarized; 2) the recent serious problems of aerosol pollution and the shortage of current aerosol research in China are pointed out; and 3) the necessity to enhance aerosol research in China is emphasized.  相似文献   
7.
甲藻(Dinophyta)凯伦藻科(Kareniaceae)的分类学研究与展望   总被引:2,自引:0,他引:2  
凯伦藻科(Kareniaceae)是甲藻门中较新建立的一个科。凯伦藻科种类广泛分布于全球海域,目前已报道3属30个种。由于该科大部分种类频发藻华,严重威胁近海生态安全和水产养殖,因而备受关注。自20世纪90年代起,我国沿岸也逐渐成为凯伦藻藻华的重灾区,凯伦藻曾引发我国最严重的几次藻华事件。本文对本科种类分类学特征进行详细描述,翻译其中文名,编制属、种分类检索表,以期为我国凯伦藻生物多样性研究以及凯伦藻藻华防治提供基础而必要的种源信息。  相似文献   
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Spatial Interpolation of Daily Precipitation in China:1951-2005   总被引:4,自引:0,他引:4  
Climate research relies heavily on good quality instrumental data; for modeling efforts gridded data are needed. So far, relatively little effort has been made to create gridded climate data for China. This is especially true for high-resolution daily data. This work, focuses on identifying an accurate method to produce gridded daily precipitation in China based on the observed data at 753 stations for the period 1951-2005. Five interpolation methods, including ordinary nearest neighbor, local polynomial, r...  相似文献   
9.
A remarkable character of the Fangshan (房山) granodiorite isthe abundance of the large phenocrystic orthoclase perthite throughoutthe central part of the igenous body. They project on the weathered  相似文献   
10.
DQ-87型地球物理数据采集和处理系统   总被引:6,自引:1,他引:6       下载免费PDF全文
在地球物理学领域内经常遇到各种观测资料,其信号频率范围属于甚低频和超低频。例如地磁脉动,由电离层反射的无线电波频率的多普勒偏移,哨声,声重力波以及一般的地磁、地电、地震资料,大气参量的变化及其湍动等等,它们的频率范围从千分之几赫兹到数千赫兹。这些资料的收集和整理通常是分开的,由于记录的资料通常并不是数据化的,  相似文献   
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