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1.
湖泊是气候变化的敏感指示器,研究其动态变化对揭示全球气候变化及水资源利用与管理具有重要意义。本文以长江源区多尔索洞错-米提江占木错为研究对象,应用Landsat-5/7/8卫星和高分遥感影像,分析了1989—2021年湖泊面积变化的时空特征,并探讨了冰湖-冰川对气候变化的响应。结果表明,1989—2021年间,多尔索洞错-米提江占木错湖泊平均面积为1 011.37 km2,由1989年的872.07km2扩张至2021年的1 119.5 km2,平均扩张率为8.62 km2·a-1。从年代际变化来看,21世纪初期湖泊面积扩张最明显,尤其是在湖泊北部、西北部及南部地区;20世纪90年代增长最为缓慢。1990—2020年各拉丹冬冰川面积从1990年的797.85 km2缩小至2020年的766.19 km2,减少了31.66 km2,缩减率为1.106 km2·a-1。20... 相似文献
2.
基于多源数据的近50 a玛纳斯河流域冰川变化分析 总被引：3，自引：3，他引：0
我国新疆玛纳斯河流域的冰川变化极大影响流域内及其周边地区的经济社会发展.使用国产高分一号(GF-1)遥感影像和Landsat8数据,分别通过基于多源数据的冰川识别方法和波段比值法获取了2013年玛纳斯河流域冰川信息,结合玛纳斯河流域第一次(1964年)、第二次(2009年)冰川编目数据与1998年、2003年TM影像冰川目视解译结果等四期的冰川边界矢量数据,对玛纳斯河流域1964-2013年50 a来的冰川变化特征进行了综合分析.研究结果显示:玛纳斯河流域冰川自2009年以来有略微增加的趋势,2013年冰川面积比2009年增加了10.25 km2,这在一定程度上抑制了长期以来冰川的快速消融;1964-2013年,玛纳斯河流域的冰川总体呈减少趋势;冰川面积从1964年的673.61 km2减少到2013年的512.07 km2,面积减少161.54 km2,减少23.98%;近50 a来,流域内冰川面积在海拔4500 m及以上呈净增加趋势,而在海拔4500 m以下呈净减少趋势,冰川在海拔(4000±100) m左右退缩的速率最大,高达0.5 km2·a-1;冰川面积的减少主要体现为大量的冰舌后退和小面积冰川的快速消融,超过85%的冰川冰舌后退距离在200 m以上;该流域的冰川变化主要集中在南、北两个坡向,在南坡向上出现明显的先减少和后增加的变化趋势;1964-2013年,玛纳斯河流域的气温和降水量呈较明显的增加趋势,线性增加率分别为0.26℃·(10a)-1和16.07 mm·(10a)-1.研究结果表明气温的持续升高和降水量的增加分别是导致玛纳斯河流域冰川减少期和增加期形成的主要原因. 相似文献
3.
利用Landsat卫星影像,采用面向对象分类方法提取珠穆朗玛峰自然保护区湖泊信息,分析了湖泊动态及对区域气候变化的响应关系。结果表明：（1）2015年保护区湖泊总面积为489.07 km2,构造湖、河成湖、冰川湖分别占总面积的77.3%、2.6%、20.1%。（2）1975-2015年,保护区内各类湖泊面积变化速率不同,冰川湖最大（1.05 km2·a-1）,构造湖次之（-0.85 km2·a-1）,河成湖最稳定（0.013 km2·a-1）;保护区南坡冰川湖面积变化速率（0.53 km2·a-1）略大于北坡（0.52 km2·a-1）。（3）北坡构造湖、河成湖对区域气候的响应呈阶段性变化规律,1975-2000年珠峰地区气候呈暖湿化趋势,2000年构造湖、河成湖面积达到峰值,两类总计增加22.8 km2;2000-2015年转变为显著的暖干气候,构造湖、河成湖面积均呈减少趋势,总共减少57.16 km2。随着区域气候的变暖,冰川湖总面积不断扩大,近40年间冰川湖面积累计增加43.06 km2。（4）灰色关联度分析显示,年极端低温对构造湖面积变化影响最显著,年均气温对冰川湖起主导作用,年均相对湿度对河成湖影响最大。较其他气候因子而言,降水量对各类湖泊面积变化的影响均最小。 相似文献
4.
南疆地区经济发展对荒漠化程度的影响研究 总被引：1，自引：0，他引：1
荒漠化程度的变化对南疆地区来说是生态系统退化的表现。应用NDVI数据,利用图像处理软件ENVI对南疆地区荒漠化程度进行分析,结果表明： 1952-1983年之间南疆地区荒漠化面积约增长11%,其中重度荒漠化面积约增14.21%左右,而中轻度荒漠化面积增7%~8%。1983-1993年荒漠化保持着基本稳定的状态。在21世纪初,即从2000年、2005年、2010年、2014年4期遥感数据解译分析结果来看, 2000年荒漠化总面积达到96.11×104 km2,约占总面积的90.41%,其中严重荒漠化面积为72.93×104 km2,重度荒漠化面积为15.76×104 km2,中轻度荒漠化面积为7.42×104 km2,到了2014年,荒漠化总面积达到95.31×104 km2,比2000年下降1.24%,但严重中轻度荒漠化土地面积不断发生变化。通过分析发现,荒漠化程度变化主要是人类活动和自然因素共同作用所导致的。 相似文献
5.
1956—2017年河西内流区冰川资源时空变化特征 总被引：7，自引：6，他引：1
基于修订后的河西内流区第一、 第二次冰川编目数据及2016—2017年Landsat OLI遥感影像, 对河西内流区1956—2017年冰川时空变化特征进行分析。结果表明： ①河西内流区现有冰川1 769条, 面积976.59 km2, 冰储量约49.82 km3。冰川面积以介于0.1 ~ 10 km2的冰川为主, 数量以<0.5 km2的冰川为主。祁连山是该区域冰川集中分布区, 其冰川数量、 面积和冰储量分别占该区域冰川相应总量的98.47%、 97.52%和97.53%。②疏勒河流域（5Y44）冰川数量、 面积及冰储量最多（最大）, 冰川平均面积为0.81 km2, 石羊河流域（5Y41）最少（最小）。从四级流域来看, 宁掌等流域（5Y445）冰川最为发育, 冰川数量、 面积及储量均最大, 宰尔莫合流域（5Y446）冰川平均面积最大（1.80 km2）, 夹道沟-潘家河流域（5Y422）最小, 仅有0.05 km2。③近60年河西内流区冰川数量减少556条, 面积减少417.85 km2, 冰储量损失20.16 km3。面积介于0.1 ~ 0.5 km2之间的冰川数量与面积减少最多（457条和 -117.49 km2）, 海拔4 400 ~ 5 400 m区间是冰川面积集中退缩的区域（98.55%）, 北朝向冰川面积减少最多（-219.92 km2）且冰川退缩速率最快（-3.61 km2·a-1）。④1956—2017年河西内流区各流域冰川面积均呈退缩态势, 区内冰川变化呈自西向东逐渐加快的趋势, 但有3条冰川在1986—2017年出现不同程度的前进, 气温升高是该区域冰川退缩的主要原因。 相似文献
6.
中亚干旱区咸海面积变化与人类活动及气候变化的关联研究 总被引：4，自引：2，他引：2
咸海是亚洲仅次于里海的第二大内陆咸水湖, 20世纪60年代以来湖泊面积急剧萎缩。基于1960 - 2018年咸海的面积数据、 CRU气温和降水数据以及咸海流域灌溉面积、 水库容量等资料, 定量分析了1960年以来咸海湖泊面积的变化情况, 并从气候变化与人类活动两方面探究了咸海面积变化的主要影响因素。结果表明： 1960 - 2018年咸海的面积由6.85×104 km2持续萎缩至（8.32±0.19）×103 km2, 共减少了（6.02±0.02）×104 km2（约87.85%）, 其中1960 - 2009年面积萎缩了（5.94±0.02）×104 km2（约86.77%）, 而在2009 - 2018年其面积萎缩速率明显放缓, 减少了740.04 km2（约8.17%）。统计结果显示, 1960年以来强烈的人类活动（主要表现为灌溉用水和水库储水量的持续增加）是导致咸海面积急剧萎缩的主要因素, 其对咸海面积变化的影响远大于气候变化。在中亚地区气候继续向暖湿变化的背景下, 咸海流域应尽快调整以农业灌溉为主的用水结构, 否则在上游冰川融水达到峰值后, 咸海可能面临干涸的危险。 相似文献
7.
1980-2010年西藏波密地区典型冰川变化特征及其对气候变化的响应 总被引：4，自引：3，他引：1
运用遥感(RS)与地理信息系统(GIS)技术, 结合波密县1960-2010年气象数据, 分析了西藏波密地区冰川的主要分布特征和典型大冰川1980-2010年的时空变化. 结果显示: 波密县共有冰川数量2 040条, 总面积为4 382.5 km2, 其中, 分布在海拔4 000~6 000 m的高山冰川总面积达4 086 km2, 占冰川总面积的93.2%; 南坡分布冰川1 504条, 面积3 180.04 km2, 分别占波密冰川总量的73.73%和72.56%, 而北坡占还不到三分之一. 提取1980、 1990、 2000和2010年4期面积大于20 km2的24条大冰川面积进行对比分析, 1980-2010年间波密县大冰川面积总体呈减小趋势, 由1980年的1 592.78 km2退缩至2010年1 567.04 km2, 共退缩了25.74 km2; 其中, 1980-1990年冰川变化贡献最大, 冰川面积退缩了16.62 km2, 占冰川总面积退缩量的64.6%. 波密县气象站数据显示, 50 a来冰川退缩主要受温度持续上升的影响, 降水量变化对冰川变化影响不大. 相似文献
8.
基于东北黑土地1∶250 000土地质量地球化学调查数据,按照《土地质量地球化学评价规范》和《土壤环境质量农用地土壤污染风险管控标准（试行）》,对讷河市土壤养分、土壤环境质量、土壤综合质量及绿色产地适宜性进行评价. 结果显示讷河市土地肥沃,环境清洁,适合于发展绿色农业：1）土壤养分单指标N、P、K、有机质、CaO、MgO、Fe2O3、S、B、Zn、Mn、Cu、Mo、Co、Ge、V共16项中,除Cu、Zn为较缺乏和Ge、B缺乏外,其他指标均为丰富和较丰富;土壤养分综合等级以较丰富和中等为主,分布面积分别为3 666.74 km2和2 574.11 km2,占全区面积的56.94%和39.97%. 2）土壤环境质量以一等（无风险）为主,一等区面积6 435.78 km2,占全区面积的99.94%;二等（风险可控）区面积仅4 km2,占0.06%. 3）全区土壤质量综合等级以优质为主,优质土壤面积3 806.06 km2,占全区面积的59.11%;良好级土壤面积2 574.11 km2,占39.97%;中等级土壤面积59.61 km2,占0.92%;没有四等（差等）和五等（劣等）土壤. 4）符合一级绿色食品产地的土壤面积为6 461.5 km2,占全区面积的97.5%;符合二级绿色食品产地的土壤面积为38.1 km2,占全区面积的0.58%;不符合绿色食品产地的土壤面积为65.6 km2,占全区面积的0.99%. 相似文献
9.
选取青海羌塘盆地1976-2010年5期遥感影像, 解译了该区域面积大于1 km2以上的67个湖泊面积.结果表明: 1976-1994年, 研究区大部分湖泊呈萎缩状态, 湖泊面积萎缩了446.8 km2, 萎缩幅度为12.5%;1994-2001年, 湖泊面积由3 132.6 km2增加到3 395.2 km2, 至2007年和2010年, 湖泊持续扩张, 面积分别达到3 641.7 km2和3 836.2 km2, 其中2010年的湖泊面积较1994年增加了22.5%, 甚至超过了1976年, 2007-2010年期间湖泊扩张强度最大.同时, 分析了研究区1959-2010年的气候水文变化, 结果显示年平均气温呈显著上升趋势, 年蒸发量在1959-1980年呈下降趋势, 以后趋于稳定, 年降水量、年径流量在1998-1999年间出现了突变上升.湖泊面积对气候、水文的响应关系表明, 近期的湖泊扩张主要由降水、径流偏丰引起, 与气温上升以及蒸发变化的关系并不显著, 气温上升导致冰川退缩所增加的水量对近期湖泊扩张影响较小. 与青海湖、黄河源等地相比, 青海羌塘盆地近期气候、水文、湖泊面积发生转折的时间要提前7 a左右. 相似文献
10.
基于GIS的玛旁雍错流域冰川地貌及现代冰川湖泊变化研究 总被引：11，自引：0，他引：11
基于多源多时相的数字遥感影像、地形图和DEM数据,利用遥感(RS)和地理信息系统(GIS)技术,对西藏玛旁雍错流域冰川地貌类型和空间分布进行了研究,并对流域内近30 a来冰川和湖泊的变化进行分析.结果表明:1974-2003年玛旁雍错流域冰川总面积减少了7.27 km2,平均退缩速率0.24 km2·a-1;湖泊总面积减少37.58 km2,平均退缩速率1.25 km2·a-1.多时相的监测表明,冰川在加速退缩,且阳坡冰川的消融速度大于阴坡,坡度陡、面积小的冰川消融比例大于坡度缓、面积较大的冰川;湖泊面积先减少后有所增加,但总面积还是减少了,不少小湖泊消失.分析流域附近气象资料可知,气温上升和降水量减少是玛旁雍错流域内冰川消融与退缩的主要原因. 相似文献
11.
本文以政府间气候变化专业委员会（IPCC）于2001年专门报告中关于21世纪内全球气候变化的温度和海平面变化的预估为前提。简要介绍了中国珊瑚礁的定位、类型和分布,对其进行了成熟度分类,评估了全球海平面变化对中国珊瑚礁的影响。据预测,21世纪我国各海域海平面上升以南海最大,为32 ~ 98cm,其平均上升速率为0.32 ~ 0.98cm/a。从海平面上升速率与珊瑚礁生长速率的理论对比分析,中国珊瑚礁基本上能与前者同步生长,即使海平面以预估高值上升,也不会威胁其生存。从中国珊瑚礁成熟度较高、其生长趋势以侧向生长为主的现实状况出发,未来全球海平面上升能为其创造向上生长的有利条件。从古地理学“将古论今”观点出发,自全新世6000aBP以来曾存在过的高海平面和较高表层海水温度的历史,也可以佐证,21世纪的全球海平面上升不会对中国珊瑚礁的存在和发育造成威胁。现存的珊瑚礁岛应对于全球海平面上升,可以做到“水涨岛高”,它们能够屹立于上升了的未来海平面之上;但对于岛上的人工建筑物则会被浸、被淹,或被淘蚀和破坏,因此必须根据海平面上升的幅度和速率,采取相应的防御措施。 相似文献
12.
Studies on the coral reefs of the South China Sea (SCS) was the theme of the 6th Session of the 3rd Conference on Earth System Science (CESS) in Shanghai, 2014. This session discussed the most recent study developments on the SCS coral reefs, including coral reefs’ responses to global changes, coral reefs’ records on past climatic variations, and the activities about constructions and oil gas explorations in the coral reefs areas of the SCS. Disturbed by intensive anthropogenic activities and global climate warming, coral reefs in the SCS have declined dramatically, reflecting the up to 80% decrease of living coral cover and many areas having less than 20% of living coral cover. Geochemical data of SCS coral skeletons clearly show that since the Industry Revolution, the pollution situation of the SCS have dramatically increased and the seawater pH values have been continuously lowering, i.e. oceanic acidification. All these environmental phenomenon are further stressing the healthy development of the coral reef ecosystem in the SCS. Meanwhile, the poor coral reef ecosystems in the SCS are facing more anthropogenic disturbances such as coastal developments and engineering constructions. Obviously, the SCS coral reefs will be faced with more environmental challenges in the coming future. We therefore suggest that the policy makers should realize the extreme importance and the fragile of the coral reef ecosystems, and scientifically and with great cautions design construction project when in coral reef areas. We initiated the concept of “green engineering” for future developments in coral reef areas. Coral reefs are widely spreading in the whole SCS, and most of them developed since Miocene. Variations in coral reef structures provide good future oil-gas exploration. Because the SCS coral reefs have a long-developing history and a wide spatial distribution, they provide great potential in recording past environmental changes. 相似文献
13.
Alina M. Szmant 《Estuaries and Coasts》2002,25(4):743-766
Coral reefs are degrading worldwide at an alarming rate. Nutrient over-enrichment is considered a major cause of this decline because degraded coral reefs generally exhibit a shift from high coral cover (low algal cover) to low coral cover with an accompanying high cover and biomass of fleshy algae. Support for such claims is equivocal at best. Critical examination of both experimental laboratory and field studies of nutrient effects on corals and coral reefs, including the Elevated Nutrient on Coral Reefs Experiment (ENCORE) enrichment experiment conducted on the Great Barrier Reef, does not support the idea that the levels of nutrient enrichment documented at anthropogenically-enriched sites can affect the physiology of corals in a harmful way, or for most cases, be the sole or major cause of shifts in coralalgal abundance. Factors other than nutrient enrichment can be significant causes of coral death and affect algal cover, and include decreased abundance of grazing fishes by fishing, and of grazing sea urchins to disease; grazing preferences of remaining grazers; temperature stress that kills coral (i.e., coral bleaching) and creates more open substrate for algal colonization; sedimentation stress that can weaken adult corals and prevent coral recruitment; coral diseases that may be secondary to coral bleaching; and outbreaks of coral predators and sea urchins that may be secondary effects of overfishing. Any factor that leads to coral death or reduces levels of herbivory will leave more substrate open for algal colonization or make the effects of even low-level enrichment more severe. Factors that contribute to an imbalance between production and consumption will result in community structure changes similar to those expected from over-enrichment. Over-enrichment can be and has been the cause of localized coral reef degradation, but the case for widespread effects is not substantiated. 相似文献
14.
Kekuewa Samuel A. H. Courtney Travis A. Cyronak Tyler Kindeberg Theodor Eyre Bradley D. Stoltenberg Laura Andersson Andreas J. 《Aquatic Geochemistry》2021,27(4):241-268
Globally, coral reefs are threatened by ocean warming and acidification. The degree to which acidification will impact reefs is dependent on the local hydrodynamics, benthic community composition, and biogeochemical processes, all of which vary on different temporal and spatial scales. Characterizing the natural spatiotemporal variability of seawater carbonate chemistry across different reefs is critical for elucidating future impacts on coral reefs. To date, most studies have focused on select habitats, whereas fewer studies have focused on reef scale variability. Here, we investigate the temporal and spatial seawater physicochemical variability across the entire Heron Island coral reef platform, Great Barrier Reef, Australia, for a limited duration of six days. Autonomous sensor measurements at three sites across the platform were complemented by reef-wide boat surveys and discrete sampling of seawater carbonate chemistry during the morning and evening. Variability in both temporal and spatial physicochemical properties were predominantly driven by solar irradiance (and its effect on biological activity) and the semidiurnal tidal cycles but were influenced by the local geomorphology resulting in isolation of the platform during low tide and rapid flooding during rising tides. As a result, seawater from previous tidal cycles was sometimes trapped in different parts of the reef leading to unexpected biogeochemical trends in space and time. This study illustrates the differences and limitations of data obtained from high-frequency measurements in a few locations compared to low-frequency measurements at high spatial resolution and coverage, showing the need for a combined approach to develop predictive capability of seawater physicochemical properties on coral reefs.
相似文献15.
Coral reefs are often constrained by diagenesis as a sound environmental archive. The correct understanding and evaluation of diagenesis is the key to the paleoenvironmental reconstruction of coral reefs. The diagenesis of coral reefs mainly includes cementation, dissolution, neomorphism and dolomitization etc. On the one hand, the diagenesis itself can record the paleoenvironment that coral reefs underwent, such as sea-level fluctuation, climate change, change of sea water, hydrothermal alteration, microbial activity and so on. The diagenetic evolution thus can be used for the reconstruction of paleoenvironment change. On the other hand, diagenesis also destroys the original environmental information which recorded of coral reefs recard, and it is necessary to know the degree of the impact of diagenesis. In the future, we should pay more attention to the study on the relationships among diagenesis, modern climate, sea-level change, atmospheric water transformation and microbial activity. It can provide more accurate and longer time series of paleoenvironmental information that coral reefs recorded. 相似文献
16.
Sami Ullah Muhammad Shafique Muhammad Farooq Muhammad Zeeshan Matthias Dees 《Arabian Journal of Geosciences》2017,10(3):67
Satellite images of various spatial resolutions and different image classification techniques have been utilized for land cover (LC) mapping at local and regional scale studies. Mapping capabilities and achievable accuracies of LC classification in a mountain environment are, however, influenced by the spatial resolution of the utilized images and applied classification techniques. Hence, developing and characterizing regionally optimized methods are essential for the planning and monitoring of natural resources. In this study, the potential of four non-parametric image classification techniques, i.e., k-nearest neighbor (k-NN), support vector machine (SVM), random forest (RF), and neural network (NN) on the accuracy of LC classification was evaluated in the Hindu Kush mountains ranges of northern Pakistan. Moreover, we have assessed the impact of the spatial resolution of the utilized satellite imagery, i.e., SPOT-5 with 2.5 m and Landsat-8 with 30 m on the accuracy of the derived LC classification. For the classification of LC based on SPOT-5, we have achieved the highest overall classification accuracy (OCA) = 89% with kappa coefficient (KC = 0.86) using SVM followed by k-NN, RF, and NN. However, for LC classification derived from Landsat-8 imagery, we achieved the highest OCA = 71% with KC = 0.59 using RF and SVM followed by k-NN and NN. The higher accuracy derived from SPOT-5 versus Landsat-8 indicated that the results of LC classification based on SPOT-5 are more accurate and reliable than Landsat-8. The findings of the present study will be useful for the classification and mapping task of LC in a mountain environment using SPOT-5 and Landsat-8 at local and regional scale studies. 相似文献
17.
珊瑚礁是发育于热带海洋环境中由生物作用和地质作用共同形成的地质体,具有独特的新构造运动意义。南海西北部珊瑚礁记录所反映的新构造运动主要有火山活动、地壳升降运动和地震活动等。珊瑚礁区第四纪火山活跃,到现代已停止活动,部分火山构成珊瑚礁的基座,个别出露海面为火山岛;地壳升降运动差异较大,雷州半岛西南部珊瑚礁呈上升趋势,上升率为0.02~0.05mm/a;西沙群岛等岛礁地壳运动则呈下降趋势,下降率为-0.07~-0.10mm/a,岛礁中的造礁石珊瑚生长率、礁顶和灰沙岛的堆积率均相当于或大于地壳下降率与现代海平面上升率的总和;南海西北部珊瑚礁区内地震活动较强,尤其是1994年12月31日和1995年1月10日在雷州半岛西南部海域发生了6.1级和6.2 级地震,这两次地震对该区珊瑚礁的发育有较大的影响。 相似文献
18.
We investigated whether the otolith chemistry ofHaemulon flavolineatum (French grunt), a nocturnally active fish, could be used as a means to differentiate individuals occupying mangrove and coral reef habitats. In 2003, adults were collected from 9 mangrove and 10 coral reef sites throughout Turneffe Atoll, Belize. Concentrations of trace elements were measured at the edge of sagittal otoliths by laser ablated inductively coupled plasma mass spectrometry. Results of a two-factor nested MANCOVA (sites nested within habitat and covariate of fish size), used to investigate whether significant differences in otolith elemental concentrations existed between habitats (i.e., mangrove versus reef) and among sites, indicated significant differences between habitats, in terms of lithium, magnesium, zinc, and rubidium (fish from mangroves had greater concentrations than those from coral reefs), as well as among sites (for several elements). Because elemental variability existed between habitats and among sites, we asked whether this variability was sufficient to differentiate habitats and sites using separate linear discriminant function analyses (LDFA). LDFA indicated that fish were classified to the habitat (mangrove or reef) from which they were collected with a moderate degree of accuracy (correct classification of 74% and 79% for mangrove and coral reef fish, respectively), but were poorly classified to the site from which they were collected (average correct classification of 46% with a range of 0–89%). Otolith microchemical investigations ofH. flavolineatum at Turneffe Atoll can be used to identify movement between habitats, yet due to the lack of unique site-specific chemical signatures likely caused by the nocturnal movement of individuals, it will not be possible to identify specific sites from which reef fish originated. 相似文献
19.
《Comptes Rendus Geoscience》2014,346(1-2):45-51
In southern Corsica, three successive Upper Burdigalian coral reef episodes (R1, R2 subdivided into R2A and R2B subunits, and R3) developed within the Cala di Labra Formation. Tabular corals dominated under high water energy and siliciclastic input conditions. The R1 reefs show the highest coral diversity with 16 species described for the first time. A coral impoverishment was recorded in the R2 and R3 reefal episodes. The reefs did not reach a climax growth stage, except the R1 ones. Analogous to North Sardinian reefs, they reflect local vanishing conditions in the Corsican–Sardinian block through Upper Burdigalian because of constant siliciclastic inputs and deepening of the Bonifacio straight. 相似文献
20.
Pinxian Wang 《地球科学进展》2019,34(12):1222-1233
The discovery of deep sea coral forests in the spring of 2018 filled a significant gap in the benthos research and even in carbon cycling in the South China Sea. Previously, the researches of deep-sea benthos were restricted to the sediment-covered soft bottom due to the technical limitations, and the rocky hard bottom was believed to be barren of life. Using submersible technique in the mid-1990s, deep-water coral reefs were first discovered in the Atlantic Ocean, which opened a new research direction in marine sciences. Two groups of deep sea corals have been recognized: scleractinian hexacorals and gorgonian octocorals. The aragonite skeleton of the former group build up deep sea coral reefs, while the latter make up deep sea coral forests with high-Mg calcite skeleton in many gorgonian corals. All kinds of carbonate coral skeletons can record environment changes of the deep sea and provide excellent material for high-resolution paleoceanography. Although the development of deep sea coral reefs in the Pacific Ocean is hampered by its extremely shallow aragonite compensation depth, deep sea coral forests are ubiquitous in the ocean. Up to now, most parts of the Pacific have not yet explored in this respect, and deep sea corals remain outside the research scope. The present paper is a literature review and calls for attention to the deep sea forests. It starts with the composition and distribution of deep sea coral reefs and forests, followed by discussions on the significance of deep sea coral forests in marine ecology and in paleoceanographic reconstructions. 相似文献