Spartinas kolonisation og udbredelse langs Ho Bugt

Spartina sp. (“townsendii” and anglica) was introduced in the Ho Bugt area at Esbjerg in 1931. The investigation is based on a study of a sample area on the peninsula Skallingen during the years 1957, 1960, 1965 and 1970, on litterature and on a survey of the whole bay in 1971. The colonization in the different parts of the bay is described.

“Spartina shows an extremely plastic morphological response to the varying conditions of tidal submergence and exposure on different parts of the marsh. This enables it to occupy a wide range of zones occupied in other areas by a series of different plant communities.” (Ranwell, 1964).

“It has, in fact, not only taken possession of a vacant ecological niche, but has spread from this to form a serious competition to other salt marsh species of long standing.” (Goodman a.o., 1959).     

Meteorological observations 1998 at the arctic station,Qeqertarsuaq (69°15'N), Central West Greenland/Active layer monitoring in two Greenlandic permafrost areas: Zackenberg and Disko Island

An automatic meteorological station has been operating at the Arctic Station (69°15'N, 53°31'W) in West Greenland since 1990. This paper summarises meteorological parameters during 1998, including snow cover, ground temperatures and active layer development, and presents comments on the local permafrost thickness.

Abstract

Active layer monitoring in Greenland was started in 1996 and 1997, and forms part of the Circumpolar Active Layer Monitoring (CALM) Network of the International Permafrost Association (IPA). The results of the first years of this monitoring of thaw progression and maximum active layer thickness in two Greenlandic permafrost areas are presented. Two sites are in the continuous permafrost zone at Zackenberg in NE Greenland (74 °N), and one at Disko Island in W Greenland (69 °N), at the border between discontinuous and continuous permafrost.

The data collected at Zackenberg demonstrate interannual variation in the timing of thaw progression in the monitoring grid holding a seasonal snowpatch, while there is less variation in the horizontal grid without a snowpatch. The maximum active layer thickness for the two Zackenberg grids is more or less consistent for the first three years with averages from 58 to 66 cm in mid and late August. At Disko the active layer reached 71 cm in mid August 1998. Spatially the distribution of the maximum, annual active layer thickness within the grids is concordant.     

Snow,runoff, and mass balance modeling for the entire Mittivakkat Glacier (1998–2006), Ammassalik Island,SE Greenland

Geografisk Tidsskrift, Danish Journal of Geography 108(1):121–136, 2008

SnowModel, a physically-based snow evolution modeling system that includes four submodels—MicroMet, EnBal, SnowPack, and SnowTran-3D—was used to simulate eight full-year (1998/99 through 2005/06) evolutions of snow accumulation, blowing snow sublimation, evaporation, snow and ice surface melt, runoff, and mass changes on the entire Mittivakkat Glacier (31 km²) in southeast Greenland. Meteorological observations from two meteorological stations inside the glacier catchment were used as model input, and glaciological mass balance observations were used for model calibration (1998/99 through 2001/02) and validation (2002/03 through 2005/06) of winter snow simulations. As confirmed by observations, the spatially modeled end-of-winter snow water equivalent (SWE) accumulation increased with elevation up to 700–800 m a.s.l. in response to elevation, topography, and dominating wind direction, and maximum snow deposition occurred on the lee side of the ridge east and south of the glacier. Simulated end-of-summer cumulative runoff decreased with elevation and minimum runoff occurred on the shadowed side of the ridge east and south of the glacier. The modeled test period averaged annual mass balance was 65 mm w. eq. y^?1 or ～8% more than the observed. For the simulation period, the glacier net mass balance varies from -199 to -1,834 mm w.eq. y^?1, averaging -900 (±470) mm w.eq.y^?1. The glacier averaged annual modeled precipitation ranged from 1,299 to 1,613 mm w.eq. y^?1, evaporation and sublimation from 206 to 289 mm w.eq., and runoff from 1,531 to 2,869 mm w.eq. y^?1. The model simulated Mittivakkat Glacier net loss of900 mm w.eq. y^?1 contributes approximately 42% to the average simulated runoff of 2,140 mm w.eq. y^?1, indicating a mean specific runoff of 67.8 l s^?1 km^?2.     

Meteorological observations 2003 at the Sermilik Station,Ammassalik Island,Southeast Greenland

Geografisk Tidsskrift, Danish Journal of Geography 105(2):49–56, 2005

Meteorological stations have been in operation since 1993 at Sermilik (65°40'N, 38°10'W), located in southeast Greenland. This note presents meteorological observations for the year 2003, including ground temperature, orographic effect (liquid precipitation) and air temperature lapse rates between two meteorological stations, Station Nunatak (515 m a.s.l.) and Station Coast (25 m a.s.l.).     

南极阿德雷岛不同基底中真菌的分离培养及初步鉴定

为了探索南极真菌的多样性,进一步揭示其生态学角色和筛选有特定酶活性菌株,本研究对中国第27次南极科学考察采集自阿德雷岛的6份样品进行了真菌的分离培养及其胞外酶活性测定。从6份样品中共分离得到168株真菌,其中大型海藻腐烂物样品中分离到的真菌种类和数量最多,占所分离菌株总数的34.6%;对选取的15株代表菌株进行了真菌ITS1-5.8S-ITS2序列鉴定,结果表明它们分属于4个纲,8个属,其中青霉属5株,假散囊菌属、地丝菌属和枝孢属各2株,生赤壳属、曲霉属、出芽短梗霉属和unclassified Onygenales各 1株,该结果表明南极地区具有丰富的真菌物种多样性,其优势类群青霉菌。胞外酶测定显示产淀粉酶、蛋白酶和纤维素酶产生菌分别占供试菌株的64.6%、45.1%、14.6%,产纤维素酶的菌株可能在南极物质能量循环中扮演着重要角色。     

广西涠洲岛自然保护区牛角坑湿地生态修复工程

针对涠洲岛自然保护区牛角坑湿地所出现的水源不足、生境退化、生物量下降等问题,通过实施牛角坑湿地保水工程、鸟类饵料生物培殖工程、鸟类栖息地通道修复工程、监测基础设施建设工程,实施湿地生态修复。重点实施沼泽-觅食地-引水渠-湿地调节库4级保水工程来提高牛角坑湿地的保水能力,把牛角坑间歇性沼泽地改造为永久性湿地,提高牛角坑湿地对鸟类的承载力,丰富涠洲岛自然保护区的生物多样性。     

平潭综合实验区海坛岛土地利用变化及景观格局研究

在Rs和GIS技术支持下,以2007年的LandsatTM遥感影像图和平潭综合实验区总体规划主岛发展指引图为基础数据,对未来平潭综合实验区主岛海坛岛的土地利用与景观格局变化进行了分析．结果表明：在规划实施后,人类活动对景观的干扰强度越来越大,将导致建设用地面积大量增加,区域景观类型趋向单一,平均斑块面积增大,斑块数量减少,景观多样性与均匀度降低．景观格局变化的主要驱动力因素是政府政策的影响和人口变化等．     

西南极利文斯顿岛火山岩多种成因过程的地球化学证据

利文斯顿岛火山岩是南极南设得兰岩浆弧的一部分。对岩石的Ｓｒ、Ｎｄ、Ｐｂ同位素组成以及８７Ｓｒ／８６Ｓｒ与１／Ｓｒ、Ｒｂ、Ｋ和ＳｉＯ２关系的研究表明,利文斯顿岛火山岩具有不同的源区特征。百耳斯半岛和史莱夫角的火山岩、西多斯角的粗玄岩和第三纪的英云闪长岩显示出同成因的特点,和依诺特角第四纪橄榄玄武岩一样,它们均具有原生地幔的同位素组分,源区岩浆可能直接来自上地幔。汉那角和中利文斯顿岛火山岩岩浆则受到地壳成分的混染。不相容元素对Ｌａ／Ｓｍ－Ｌａ和Ｃｅ／Ｙｂ－Ｃｅ的研究进一步显示出,上述不同产地的岩石分别为不同源岩浆不同程度部分熔融的产物。结合岩相学和岩石化学特征的研究,提出百耳斯半岛和史莱夫角的火山岩以及西多斯角的粗玄岩是上地幔发生部分熔融所生成的玄武岩岩浆从深部岩浆囊沿构造薄弱带直接喷出形成的。古生代基底岩系的存在对中利文斯顿岛和汉那角火山岩的成因过程有重要的影响,即来自深部岩浆囊的原始岩浆在上地壳中的浅部岩浆囊受到了壳源物质混染。更新世－现代火山岩的源区岩浆直接自上地幔部分熔融生成,火山作用与晚新生代时该区的拉张构造有关。