2010年5月与2013年6月黄、渤海大型底栖动物群落组成和结构的比较研究

基于2010年5月和2013年6月采集的黄、渤海海域的大型底栖动物数据,对该海域大型底栖动物的种类组成和群落结构等进行了研究,对该海域大型底栖动物群落结构的时间和空间差异进行了分析,并利用AMBI和m-AMBI生物指数对各站位的生态质量状况进行了评估。研究结果表明:在2010年5月和2013年6月所采站位的大型底栖动物共有131种,其中软体动物和甲壳动物占据了较大比例的物种数量,分别为51种和42种;其次为鱼类、多毛类和棘皮动物。该海域的优势物种为日本鼓虾 Alpheus japonicus、日本褐虾 Crangon hakodatei、司氏盖蛇尾Stegophiura sladeni和奇异指纹蛤Acila mirabilis,其中司氏盖蛇尾具有最大的丰度和优势度。生物指数(AMBI和m-AMBI)的结果显示黄、渤海区域底栖生态环境仍相对稳定,但与历史资料比较得知,该海域大型底栖动物生存环境整体趋于恶化。     

Contrasting hydrography and phytoplankton distribution in the upper layers of cyclonic eddies in the Mozambique Basin and Mozambique Channel

Hydrographic data collected in cyclonic eddies in the Mozambique Channel and Basin revealed notable differences in temperature and salinity at a depth of 100 m, the upper mixed layer, the nitracline depths, and vertical distribution of chlorophyll-a (Chl-a). Differences in temperature and salinity did not show any consistent patterns. In contrast, the differences in the upper mixed layer, nitracline depths and the vertical Chl-a profile appeared to be driven by combined effects of eddy dynamics (i.e. shoaling of isopleths) and the seasonal variation in light availability and mixing conditions in the upper layers. Cyclonic eddies studied during austral spring and summer in the Mozambique Channel exhibited shallower upper mixed layers and nitracline depths, and deeper euphotic zones. Distinct subsurface Chl-a maxima (SCM) were associated with the stratified conditions in the upper layers of these eddies. In contrast, a cyclonic eddy studied during mid-austral winter in the Mozambique Basin had a shallower euphotic zone, deeper upper mixed layer and uniform Chl-a profiles. Another eddy sampled in the Mozambique Basin toward the end of winter showed a less pronounced SCM and roughly equal euphotic zone and upper mixed layer depths, suggestive of a transition from a well-mixed upper layer during winter to stratified conditions in summer.     

中哈油气资源合作面临的挑战、趋势及启示

中哈两国在资源、地缘优势和共同利益等方面具有合作的互补性和必要性,从我国经济可持续发展的长远利益考虑,加强中哈油气合作具有重要意义。通过分析两国油气合作面临的挑战,阐述了今后合作的发展方向和趋势,进而对中哈乃至中亚国家的资源合作给出了思路。     

基于多格网算法的卫星图像恢复

将求解二次椭圆偏微分方程问题的多格网算法应用到卫星影像的恢复中。其基本思想是在将由总变分求极小生成的偏微分方程离散成为差分方程的过程中,采用不同大小的格网。在取得较好恢复结果的同时,提高了传统图像恢复算法的运算效率,降低了恢复运算所需要的时间。     

Seasonal growth in brown trout in two New Zealand streams

Brown trout Salmo trutta Linn, were marked with individual tags and recaptured throughout a year in two small Canterbury streams. The growth recorded showed a marked seasonal variation which differed in pattern in the two streams. There was a considerable difference in the growth rate between the two populations and fish transferred from the slow‐growth stream to the faster‐growth stream showed an immediate response to the change.     

基于多卫星融合资料的南海浪高时空分布特征研究

为提高对南海波浪场的认识, 采用基于多卫星融合的2009年9月～2011年11月的AVISO(Archiving, Validation and Interpretation of Satellite Oceanographic data)有效浪高格点数据对南海浪高的月变化特征进行分析, 并结合南海的波浪特征和地形特点, 将南海划分为6个海区, 讨论南海浪高的空间分布规律。研究发现南海浪高具有以下2个特征: (1)南海浪高表现为由东向西、由北往南递减: 北部深水区>北部陆架区>南海中部≈北部湾>南部陆架区>泰国湾。(2)浪高的月变化与季风的变化密不可分: 10月～次年3月(冬季风影响期间)>4月和9月(季风转换期)>5月～8月(夏季风影响期间), 1月最大, 5月最小。该研究成果对开展南海海浪的中长期预报、保障南海资源开发和军事安全等有一定的借鉴意义和参考价值。     

近20年来胶东半岛南部典型海岸带地区岸线变迁的遥感分析

通过近20年来胶东半岛南部Landsat TM遥感影像及Alos、Spot等高分辨率遥感影像的解译,结合GIS等手段和海岸带调查数据,制作了典型海岸带地区海岸线变化图和海岸带土地利用分类图,并对不同时期典型海岸带地貌的演变进行了分析,阐述了岸线变迁的控制因素及人类活动的影响。     

Diversity and temporal fluctuations of epiphytes and sessile invertebrates on the rhizomes Posidonia oceanica in a seagrass meadow off Tunisia

The aim of this work is to study the temporal dynamics of rhizome epiphytes and sessile animals living on the rhizomes of the seagrass Posidonia oceanica in the east of Tunisia. Surveys were conducted in October 2009, and in January, April and August 2010 on a fringing reef located in Chebba. Rhizomes were sampled by SCUBA diving at three stations. Samples were examined with a microscope to estimate the cover of macroinvertebrate and macroalgal organisms on the top 10 cm of each rhizome. Results revealed a high diversity of epiphytes on P. oceanica rhizomes with a dominance of red and brown algae, ascidians, and bryozoans. Distinct temporal changes were observed in Oued Lafrann, with a high January cover (winter period) for all groups. These winter increases can be attributed to: (i) the low phenological parameters of P. oceanica in winter that reduce the effects of shading, (ii) life cycles of the epiphytes and invertebrates, (iii) water motion and (iv) grazing.     

高原湖泊鱼类生长特性与形态差异研究

根据2009年8—11月洱海流域采集的2991尾鱼类样本,研究了其生长特性与形态差异。结果表明,洱海流域大部分鱼类表现为匀速生长或近匀速生长,但有两种鱼类(中华青、大理裂腹鱼)呈现强异速生长。肥满度以吃食性鱼类最高(鲫、鲤、团头鲂),滤食性鱼类次之(鲢、鳙)。对主要优势种——麦穗鱼、鲫的形态分析表明,洱海麦穗鱼、鲫种群与西湖、茈碧湖、海西海三个湖泊的麦穗鱼、鲫种群在形态上均无显著差异。西湖、茈碧湖、海西海三个湖泊的麦穗鱼种群之间以及鲫种群之间均存在种群间差异(C.D<1.28),其中茈碧湖、海西海两个湖泊的鲫种群在眼径/头长性状上的差异达到亚种水平(C.D=1.5)。     

1998～2010年夏季台湾海峡西部沿岸海水遥感透明度的年际变化

通过比较分析不同的透明度卫星遥感算法,提出将一个基于固有光学特性的、适用于沿岸海域的算法应用于台湾海峡西岸海域,反演获得1998～2010年SeaWiFS遥感透明度时间序列.根据这组时间序列数据,发现该海域夏季透明度低值(<4 m)年份出现在1998、2001和2006年,高值(最高值达到10 m)年份出现在1999、2004和2010年.控制这一年际变动的因素,以目前有限的数据来看,主要是径流与上升流共同引发的水华强度的变化.此外,该海域透明度在研究时段内没有呈现一定的变化趋势,甚至在2006年之后,似乎在持续加深,说明海峡西岸活跃的经济活动,在1998～2010的13 a间,暂时没有对沿岸水质产生显著的破坏性的影响.