两类强度厄尔尼诺和拉尼娜事件对中国近海鲐鱼栖息地的影响

鲐鱼是中上层鱼类,具有较高经济价值,其种群受到气候和海洋环境的显著影响。本文根据2006-2015年7-9月中国远洋渔业数据中心提供的中国近海鲐鱼捕捞和海表温度以及海面高度两个关键环境因子的数据,构建了基于捕捞努力量的鲐鱼综合栖息地指数模型,分析研究了在不同强度厄尔尼诺和拉尼娜条件下鲐鱼栖息地适宜性的变动规律。通过计算和交叉验证,结果发现,基于算术平均法的栖息地模型能够较好地预测鲐鱼渔场栖息地适宜性指数。空间相关性结果表明,鲐鱼渔场主要作业海域范围内海表温度异常与栖息地指数值呈显著正相关关系,而海表面高度异常与栖息地指数值呈显著负相关关系。不同强度厄尔尼诺和拉尼娜事件对鲐鱼种群影响不同,具体表现为:相对于中强度厄尔尼诺事件（或中强度拉尼娜事件）,超强厄尔尼诺事件（或强拉尼娜事件）驱动鲐鱼主要作业海域内温度下降（或上升）,海面高度上升（或降低）,鲐鱼渔场适宜栖息地面积显著减小（或增大）,导致鲐鱼单位捕捞努力量渔获量骤减（或显著增加）。研究表明,中国近海鲐鱼栖息地适宜性与厄尔尼诺和拉尼娜事件显著相关,且随着异常气候事件强度的不同而发生变化。     

半分析模型在近岸及河口水体透明度反演应用研究

Secchi depth(SD, m) is a direct and intuitive measure of water's transparency, which is also an indicator of water quality. In 2015, a semi-analytical model was developed to derive SD from remote sensing reflectance, thus able to provide maps of water's transparency in satellite images. Here an in-situ dataset(338 stations) is used to evaluate its potential ability to monitor water quality in the coastal and estuarine waters, with measurements covering the Zhujiang(Pearl) River Estuary, the Yellow Sea and the East China Sea where measured SD values span a range of 0.2–21.0 m. As a preliminary validation result, according to the whole dataset, the unbiased percent difference(UPD) between estimated and measured SD is 23.3%(N=338, R~2=0.89), with about 60% of stations in the dataset having relative difference(RD)≤20%, over 80% of stations having RD≤40%. Furthermore, by excluding the field data which with relatively larger uncertainties, the semi-analytical model yielded the UPD of 17.7%(N=132,R~2=0.92) with SD range of 0.2–11.0 m. In addition, the semi-analytical model was applied to Landsat-8 images in the Zhujiang River Estuary, and retrieved high-quality mapping and reliable spatial-temporal patterns of water clarity. Taking into account the uncertainties associated with both field measurements and satellite data processing, and that there were no tuning of the semi-analytical model for these regions, these findings indicate highly robust retrieval of SD from spectral techniques for such turbid coastal and estuarine waters. The results suggest it is now possible to routinely monitor coastal water transparency or visibility at high-spatial resolutions from measurements, like Landsat-8 and Sentinel-2 and newly launched Gaofen-5.     

Two new species of medusae (Cnidaria) from the coastal waters of the northern Beibu Gulf

Medusae in 116 samples collected from the coastal waters of the northern Beibu Gulf during four seasonal oceanographic cruises from October 2017 to August 2018 were analyzed. In total, 34 species were identified. Two of the species are new to science, Proboscidactyla pentacanalis Xu, Chen & Yang sp. nov. and Helgicirrha apapillata Xu, Chen & Wang sp. nov., and three species are newly recorded in the Beibu Gulf, i.e., Hydractinia vacuolata Xu & Huang, 2006, Proboscidactyla flavicirrata Brandnt, 1834 and Phialella macrogona Xu, Huang & Wang, 1985. Collections of the species were deposited at the Third Institute of Oceanography, Ministry of Natural Resources.     

基于主成分分析法的闽江口及其近岸水域水质评价

选取2016年4月、7月和10月闽江口及其近岸水域7个调查点位的盐度、悬浮物、pH、溶解氧、化学需氧量、氮营养盐和重金属等15项监测指标数据,采取主成分分析法分析了该水域的水质,明确影响该水域水质的主要污染因子。结果表明：15项监测指标转换提取为4个主成分,解释82.153%的方差。从时间分布来看,闽江口及其近岸水域在4月份水质较差、10月份次之、7月份较好。从空间分布来看,近河口水质较差而远离河口水质较好。影响该水域污染水质的主要驱动因子是pH、COD、氮营养盐和Cd。研究结果对于进一步了解闽江口及其近岸水域水质情况具有重要意义,同时也为福建省海洋管理的科学决策提供支持。     

浅谈长江和黄河河口沉积物磁性特征及其对物源判别的指示

对采自长江和黄河河口的 7 个沉积物样品（28 个子样）进行了磁性测量并进行对比研究,结果表明：长江口沉积物的亚铁磁性物质含量高于黄河口,磁性强于黄河口;两河口沉积物的磁性特征均受亚铁磁性矿物的控制,以假单畴 PSD-多 畴 MD 晶粒为主,并存在一定量的超顺磁颗粒 SP,不同的是长江口存在着更多的单畴颗粒 SD;两河口的细粒级沉积物（< 0.063 mm） 磁性均强于粗粒级沉积物 （> 0.063 mm）,但黄河口细粒沉积物显示了更突出的磁性特征,表明黄河口沉积物的磁性物质更多地富集于细粒组分中;沉积物磁性特征与其所含的轻矿物类型和含量关系不大,相反,重矿物才是影响沉积物磁性特征的主要物质。沉积物的母岩、粒度、水动力条件和流域风化条件等因素影响着沉积物磁性特征。基于长江与黄河沉积物磁性参数的显著差异,建立了 Χ-ΧARM 和 SIRM-SOFT 物源判别图,初步探索了环境磁学指标在物源判别中的应用,对中国东部海域沉积物的物源研究具有一定意义。     

河口和沿岸海域生态环境质量综合评价方法评介

海洋环境管理从以往单纯的海洋污染管理已发展到当前的海洋生态环境综合管理。相应地,海洋环境质量评价也从以往单一的污染状况评价(包括水质、沉积物和生物体)发展到海洋生态环境质量综合评价。重点介绍了2种有代表性并被广泛应用的河口和沿岸海域生态环境质量综合评价方法———欧盟的“生态状况评价综合方法”和美国的“沿岸海域状况综合评价”。比较和评析了2种方法的异同和优缺点。建议尽快建立适合中国河口和沿岸海域特点的海洋生态环境质量综合评价方法以及相应的监测和管理体系。     

长江口南、北港分汊口演变与治理

按输水输沙特征,中等潮汐长江口多年来保持“三级分汊,四口入海”地貌形态格局。第二级南、北港分汊口问题已成为当今发展重要障碍之一。近百年来南、北港分汊口呈周期性冲淤演变,1971年前后共约10年,中央沙头石头沙西10 km左右的分汊口位置最佳,河势归顺,河床稳定,南、北港都畅通。现今分汊口正处于剧烈变动时期,分汊口治理,南支及其下游河段的开发与工程须认真考虑其影响与对策。     

互花米草化学治理对天津附近海域水质和沉积物质量的影响

互花米草作为入侵物种对潮间带滩涂和盐沼具有严重的生态危害性,化学方法治理互花米草具有简便、快速、彻底和成本低等特点,但化学药剂存在一定毒性,可能会对周边环境带来一系列不利影响,然而目前有关化学治理措施所带来的环境影响的研究较少。本文基于2017年8-11月的调查数据,研究了天津市永定河河口附近滩涂互花米草化学治理对附近海域海水水质和潮间带沉积物产生的影响,对调查海域海水水质和沉积物质量进行了评价。调查与评价结果表明,无机氮、活性磷酸盐和化学需氧量（COD）为调查海域的主要污染因子,硫化物为潮间带沉积物的主要污染因子。施药后特征污染物——草甘膦检测值高于本底值,所有站位均未检出磺酰脲类除草剂。综合来看,化学治理对附近海域海洋环境的影响较小。     

上海浦东YA孔微量元素变化与历史时期水体盐度波动

浦东YA孔浅地层剖面中微量元素变化的分析结果表明,B含量和B/Ga,Sr/Ba,Cl/Br比值是反映古水体盐度的灵敏指示剂,据此建立的YA孔古盐度指数变化曲线显示,该地区近数千年来曾发生过多次百年尺度的盐度波动事件,并可能与同期海面波动引起的海水进退直接相关.这一情况说明,滨海地区沉积地层中的微量元素是海面变化研究的良好的代用指标.     

Rehabilitation of Saline Wetlands, Olympics 2000 Site, Sydney (Australia)—I: Management Strategies Based on Ecological Needs Assessment

The Homebush Bay area, Sydney, site of the Olympic Games 2000, has been largely occupied for nearly a century by an abattoir, brickworks, armaments depot and waste dumps. However, it contains remnants of original ecosystems, including two estuarine wetlands, and the Olympic Co-ordination Authority (OCA), set up to manage the redevelopment of the site, is committed to the rehabilitation of these ecosystems. The ecological approaches and rehabilitation measures used for one of the wetlands are detailed. Apart from a history of disturbance, it has for 10 years been without tidal flushing. However, these wetlands are the largest remaining in the Sydney estuary, and are significant for a number of reasons including biodiversity and waterbird conservation. The ecological parameters of the site, the results of a ‘before-restoration-impact' study, and the iterative links between science and management in the introduction of the rehabilitation measures, are presented. Criteria for success are discussed, along with biomonitoring strategies to test success.