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1.
应用X射线衍射(XRD)对南海北部陆架海域225个站位表层沉积物黏土组分进行分析,结果表明,研究区黏土矿物总体以伊利石和绿泥石为主,高岭石和蒙脱石质量分数少,绿泥石、高岭石与蒙脱石质量分数呈明显的负相关关系。根据南海北部陆架海域表层沉积物中黏土矿物空间分布特征,结合邻近河流的黏土矿物组分以及洋流搬运作用,雷州半岛东部海域伊利石主要来源于广东沿海河流和珠江,绿泥石来自台湾岛,蒙脱石主要由吕宋河流提供,高岭石则由广东沿海河流和海南岛入海河流提供;雷州半岛西部海域伊利石来源于珠江,绿泥石和高岭石由红河提供,蒙脱石可能受广西入海河流携带的沉积物影响。 相似文献
2.
Long Island Sound (LIS), a large urban estuary in the northeastern USA, receives freshwater from many rivers along its northern shore. The size of these rivers varies widely in terms of basin area and discharge. The Regional Ocean Modeling System (ROMS) was applied with conservative passive tracers to identify the distribution, mixing, freshwater residence times, and storm response for all of LIS’s river systems during the summer of 2013. A watershed model was applied to overcome the lack of adequate river discharge observations for coastal watersheds. The Connecticut River was the largest contributor to riverine freshwater throughout the estuary despite its entry point near the mouth. The Connecticut River strengthened bulk stratification in the eastern LIS the most but acted to weaken stratification near the mouths of other rivers and in far western LIS by freshening waters at depth. The Housatonic and Hudson Rivers had the strongest influence on stratification in central and western LIS, respectively. Smaller coastal rivers were the most influential in strengthening stratification near the southwestern Connecticut shoreline. The influence of small coastal rivers was amplified after a major storm due to shorter storm response times relative to the larger rivers. Overall, river water was close to a well-mixed state throughout LIS, but more stratified near river mouths. Freshwater residence time estimates, meanwhile, indicated monthly to multi-seasonal time scales (43 to 180 days) and grew longer with greater distance from the LIS mouth. 相似文献
3.
为了探讨渤海东部和黄海北部稀土元素分布特征及其影响因素,对渤海东部和黄海北部138个表层沉积物样品进行电感耦合等离子体质谱法分析.结果表明:渤海东部和黄海北部沉积物的配分模式与中国黄土的接近,与周边的鸭绿江、黄河等河流输入物质也有相似性,表明研究区沉积物主要来自于周边大陆.沉积物物源判别结果显示:山东半岛近岸及其西南部沉积物主要来源于黄河,该区域沉积物分布受山东半岛沿岸流及近岸潮流影响;研究区东部沉积物稀土元素组成特征与鸭绿江沉积物组成相近,表明研究区东部沉积物可能由鸭绿江供应;研究区西北部沉积物主要来源于黄河及辽宁沿岸物质输入,局部有滦河、六股河物质存在;研究区东南部物质主要来源于黄河.对沉积物稀土元素百分含量及参数特征值进行了Q型聚类分析,将研究海域沉积物划分为4个不同的区域,分别为北黄海东部区域(Ⅰ)、山东半岛近岸周边区域(Ⅱ)、渤海东部中部区域(Ⅲ)及研究区的西北部与东南部分布区(Ⅳ). 相似文献
4.
Atlantic tomcod larvae, hatching in late February and early March 1975 and 1976 into a regime of accelerating river flows, were moved rapidly downriver from milepoint 42–54 (MP 0 is the estuary mouth) to the most seaward reaches of the estuary. This resulted in a spatiotemporal distribution markedly different from that of other Hudson River fish species. Peak tomcod density on posthatch sampling dates was observed most frequently at the George Washington Bridge station (MP 11). Correlation between movements of the 1.0‰ salt front and movements of the age-0 tomcod population was high (r=0.82); and may have been enhanced by high freshwater flows. The population epicenter was always seaward of the 1.0‰ salt front and mean distance between the two was 16–17 km. Moved by tidal and freshwater flows, the tomcod population oscillated between MP 0 and MP 43 during March–May 1973–1976. Location of the population epicenter after mid march was predicted (r2=0.76) to be seaward of the Tappan Zee Bridge (MP 30) when freshwater flows were greater than 450 m3 s?1. During flow regimes greater than 1,290 m3 s?1, the epicenter was predicted to be seaward of the George Washington Bridge (MP 11). An optimum-allocation sampling design for age-0 tomcod showed that 58% of the total effort from mid March to early June should be directed to the river region between MP 0 and MP 24, a region largely ignored in previous studies. *** DIRECT SUPPORT *** A01BY066 00013 相似文献
5.
Theory and observations of river plumes are reviewed. The importance of the Kelvin number in characterizing anticipated plume behavior is stressed. In the absence of strong external forcing, a northern hemisphere plume will turn anticyclonically and attach to the coast, where it then merges into a coastal current. Observations and theory of such coastal currents are also reviewed, with emphasis on flows over shallow continental shelves. Major unresolved questions involve the processes controlling mixing of coastal current waters with ambient shelf waters and the dynamics of the plume in the region where it attaches to the coast. 相似文献
6.
Migration patterns of Neolithic settlements on the abandoned Yellow and Yangtze River deltas of China 总被引：4，自引：0，他引：4
Archaeological records of the Neolithic settlements on the eastern China coast between 35°N and 30°N, an area covering the abandoned Yellow River and the Yangtze River delta plains, reveal that Neolithic people moved from the Yellow River basin onto the northern coast for fishing, hunting and dry-land agriculture ~ 7000 yr ago. Marine transgression interrupted their activities on the low-lying (2-5 m in elevation) coastal wetlands between 6000 and 5000 yr ago, after which they reclaimed their land near the river mouths. Their migration routes on the southern Yangtze delta plain indicate another scenario: early Neolithic communities moved onto the plain for wet-rice cultivation. Despite relative sea-level rise from 7000 to 4000 yr ago, a large number of settlements were established on the lowlands between the eastern Chenier Ridges and the western Taihu Lake depression. The Chenier Ridges, with ~ 1.0 m higher topography than the adjacent coastal area, played a role in sheltering the Neolithic people. Subsequently, settlements waned considerably, possibly due to further marine inundation combined with cold climate. The present study shows that migration patterns of the Neolithic settlements are closely associated with a gradually rising sea level between 7000 and 4000 yr ago. 相似文献
7.
Ficopomatus enigmaticus, a polychaete inhabiting the subtidal zone in the Mar Chiquita coastal lagoon, builds reef-like aggregates that facilitate silt accumulation. To describe the life cycle, samples were take monthly from September 1984 to September 1985. In contrast with other polychaetes, it has two oocyte generations per year; maturation of the oocytes takes approximately 4 mo. Temperature level and day length regime do not appear as environmental signals to the onset of oogenesis, although they possibly affect oogenesis growth. Two periods of spawning and recruitment were observed in November–December and April–May, when water temperature is above 18°C. Hermaphroditic individuals were not found. Sex ratio was male-biased in all months, significantly in November, February, and August (p<0.001). Monthly size-frequency distributions show distinct year-classes with early (November–December) and late (April–May) recruitment. Early recruited cohorts have two spawning periods during a 24-mo lifespan. Late cohorts have one spawning period during their 20-mo lifespan. The life cycle of this species can be summarized as follows: annual iteroparous—1 to 2 batches of small eggs per female during each lifespan, free spawning, planktotrophic larvae, sedentary suspension-feeder worms. 相似文献
8.
Charles A. Menzie 《Estuaries and Coasts》1980,3(1):38-54
The benthic fauna of a small cove of the Hudson River containing the aquatic plantMyriophyllum spicatum L. was studied for a one-year period. The fauna was characteristic of oligohaline zones of United States east coast estuaries. Total abundance of invertebrates retained on a 0.12 mm mesh sieve averaged 124,631 organisms m?2 (sediment and plant populations combined) and ranged up to 196,000 m?2. During the May–August period, invertebrates living on the plants comprised 16–35% of the invertebrate fauna in the cove. Chironomid larvae were the most abundant organisms on plants and the third most abundant in the sediments. Two assemblages of chironomid species were recognized; one lived solely in the sediments, the other lived primarily on the plants.Chironomus decorus andTanytarsus sp. dominated the former group andCricotopus sylvestris the latter. The chironomidDicrotendipes modestus utilized both habitats. During the May–August period, chironomid biomass on the plants comprised approximately 50% of total chironomid biomass in the cove. The mean dry-weight biomass of chironomids in the cove (1.6 g m?2) is estimated to be sixteen times greater than that of the fauna in the deeper areas of the river. Because chironomid larvae are eaten by fish and invertebrates, shallow water regions with their rich chironomid (and other fauna) may contribute importantly to the trophic dynamics of estuarine systems. *** DIRECT SUPPORT *** A01BY009 00004 相似文献
9.
河海交互作用沉积与平原地貌发育* 总被引：3，自引：15，他引：3
河流是搬运陆源泥沙的主要动力,对相邻的海岸海洋沉积动力有巨大影响。中国河流汇入海洋中的泥沙曾占全球入海泥沙的10 ％ ,现代中国边缘海大陆架在晚更新世时曾是海岸平原,河-海交互作用是形成海岸平原与浅海输积泥沙的主要因素。本文选择5个不同类型的河流展示其不同的泥沙运动与河口沉积的特性以及对相邻陆架之影响,包括: 1)强潮型动力的鸭绿江河口湾,形成从陆向海与从海向陆的双向水流交汇沉积,海岸形成潮流脊体系。 2)季风波浪为主导动力的滦河口,以泥沙的横向运动为主,形成沙坝环绕的双重海岸,沉积粒径自海向陆减小; 沿岸浪流携运泥沙向河口两侧分布,使沙坝具有沙咀状的复合特点。 3)弱潮型、多沙的黄河口,径流于两侧堆积指状沙咀,沙咀下风侧形成粉砂粘土淤泥湾,沿岸流携运泥沙向渤海湾延伸为淤泥舌。 4)径流与沿岸流组合作用的沉积模式,以长江口为代表,泥沙沿岸向南输运为主导,向海岸与向内陆架构成颗粒变细的带状沉积,外陆架出露残留砂。 5)充填河口湾的三角洲,以珠江为代表,河流分汊与会潮点泥沙堆积,悬移质扩散至湾外,被沿岸流携带沿海岸向SW运移,外陆架为残留砂沉积。20世纪80年代以来,上述河流均受到人为活动的改造影响,河流自然过程与河海交互作用效应均发生改变。本文主要以滦河三角洲为例阐述河-海交互作用与平原的地貌特征。 相似文献
10.
M. R. Jones 《Australian Journal of Earth Sciences》2013,60(3):433-444
Central Queensland lies on the passive margin of eastern Australia and owes its landscape to processes that began following rifting and opening of the Tasman Sea. The modern landscape is the result of long-term processes of landform development, and the landforms themselves are the evidence of these processes. Hence, interpreting their significance provides an understanding of long-term landscape evolution. Along the eastern Australian coast, numerous rivers drain into the sea but among these, there are two that stand out: the neighbouring Fitzroy and Burdekin Rivers in central Queensland. These two streams have by far the largest catchments of any rivers along the eastern seaboard of Australia. The Burdekin and Fitzroy catchments contain widespread remnants of Cenozoic deposits, which accumulated predominantly in fluvial and lacustrine environments established during the Palaeogene. Alluvial sediments were supplied by erosion of nearby uplands, and accumulated in depressions and basins on a prior land surface. Volcanic activity also resulted in large lava flows in central western areas. Water was the main agent of sediment transport, distributing unconsolidated deposits along the drainage networks of the time, some of which were directed inland. It is inferred that during the Palaeogene, the divide between coastward and inland draining streams was further to the east than it is at present. Several basins were located west of the former coastal divide, and were characterised by continental environments of deposition in a generally westward drainage system. With continued accumulation of sediments, individual basins overflowed and merged to form a widespread flat-lying Palaeogene landscape that concealed an earlier land surface on which bedrock was more extensive. In the Early Cenozoic, there was a change from the depositional phase that resulted in the continental sequence, to an erosional phase that developed the modern landforms. The change from deposition to erosion probably started during the Palaeogene. Erosion continued through to the present, re-exposing parts of the basal Palaeogene sequence and earlier Mesozoic land surface. The erosional phase that shaped the landforms of the modern Burdekin and Fitzroy catchments can be explained by slowly evolving drainage basins in the interior being captured by small coastal streams—the predecessors of the Burdekin and Fitzroy Rivers. The coastal streams were short and steep in comparison with those in the interior, allowing a more active erosional environment along the coast. As the coastal streams expanded, the drainage divide moved rapidly westwards. Stream capture began a phase of regional erosion, which transported large quantities of sediments to the coast. The sediments contributed to coastal and nearshore features similar to the Holocene high sea-level examples at the mouth of the Burdekin River in the north, and the Fitzroy Delta and the Keppel Coast in the south. Large volumes of sediments were also transported beyond the present coast during low sea-levels of the Cenozoic, forming similar coastal features and contributing to a major eastward bulge on the central Queensland continental shelf. The emptying of continental basins has paralleled the development of the continental shelf bulge from the coast to the Marion Plateau. 相似文献
11.
Robert W. Hastings John C. O’Herron Kevin Schick Mark A. Lazzari 《Estuaries and Coasts》1987,10(4):337-341
Sampling in the upper tidal Delaware River between Trenton, New Jersey, and Philadelphia, Pennsylvania, from July 1981 through December 1984 demonstrated the existence of a significant population of shortnose sturgeon. The sturgeon aggregate in the river channel during daylight hours, especially in the area between Trenton and Florence, New Jersey (river km 211.8 to 198.8). Occurrence in the river downstream of Florence appears to be restricted by poor water quality during summer months. Sturgeon were present in the study area throughout the year, but largest numbers were collected from May though November. No spawning was observed during this study, but presence of males with milt suggests that spawning possibly occurs in the Trenton area. Preliminary population estimates (Peterson, Schnabel and Seber-Jolly) indicate an adult population of approximately 6,000–14,000 shortnose sturgeon occupying the upper tidal Delaware River. 相似文献
12.
As part of the Microbial Exchanges and Coupling in Coastal Atlantic Systems (MECCAS) Project, crab larvae were collected in the shelf waters off Chesapeake Bay in June and August 1985 and April 1986. We conducted hydrographic (temperature, salinity, nutrients) and biological (chlorophyll, copepods) mapping in conjunction with Eulerian and Lagrangian time studies of the vertical distribution of crab larvae in the Chesapeake Bay plume. These abundance estimates are used with current meter records and drifter trajectories to infer mechanisms of larval crab dispersion to the shelf waters and recruitment back into Chesapeake Bay. The highest numbers of crab larvae were usually associated with the Chesapeake Bay plume, suggesting that it was the dominant source of crab larvae to shelf waters. Patches of crab larvae also were found in the higher salinity shelf waters, and possibly were remnants of previous plume discharge events. The distribution of crab larvae in the shelf waters changed on 1–2 d time scales as a consequence of both variations in the discharge rate of the Chesapeake Bay plume and local wind-driven currents. Downwelling-favorable winds (NW) intensified the coastal jet and confined the plume and crab larvae along the coast. In April during a downwelling event (when northwesterly winds predominated), crab zoeae were transported southward along the coast at speeds that at times exceeded 168 km d−1. During June and August the upwelling-favorable winds (S, SW) opposed the anticyclonic turn of the plume and, via Ekman circulation, forced the plume and crab larvae to spread seaward. Plume velocities during these conditions generally were less than 48 km d−1. The recruitment of crab larvae to Chesapeake Bay is facilitated in late summer by the dominance of southerly winds, which can reverse the southward flow of shelf waters. Periodic downwelling-favorable winds can result in surface waters and crab larvae moving toward the entrance of Chesapeake Bay. Approximately 27% of the larval crabs spend at least part of the day in bottom waters, which have a residual drift toward the bay mouth. There appears to be a variety of physical transport mechanisms that can enhance the recruitment of crab larvae into Chesapeake Bay. 相似文献
13.
深圳是我国经济高速发展的海滨城市。最近20年城市发展中对海洋资源开发已取得巨大成就,特别在 海港建设、围海造地开拓城市用地空间等方面。文章是配合深圳城市发展建设,从海岸海洋环境资源的调查分析 着手,对海岸带利用作出空间规划。 深圳西岸是珠江口冲积平原,正处珠江河口区的最大浑浊带范围,泥沙淤积使岸线外移,是深圳海涂资源主要 分布区。至2000年深圳在海涂区已围海造地26.8km2,按规划至2010年,将再填海28km2。西岸的填海已影响到 珠江口深槽淤积、浅滩扩大及深圳湾污染加重。至2010年,预期围海工程完毕后,已达海涂开发与海洋环境容量 的极限,今后不能再围海造地。 深圳是中国南方主要外贸进出口港,可能会发展成与上海并列为中国的两个国际航运中心。2020年运量将超 过2亿吨,西岸深水港发展将饱和,深圳深水港后备基地将在东部海岸,大鹏湾东岸下沙、南澳沿岸是理想的大型 深水港后备基地。 利用深圳河及开凿梧桐山,贯通大鹏湾与深圳湾,这一深圳运河工程是改善深圳湾海洋环境、根治深圳河污染 的重要生态工程,同时还具有航运与旅游功能。 相似文献
14.
Hurricane Floyd in September 1999 caused disastrous flooding from South Carolina to Massachusetts in the United States, with particularly severe and prolonged flooding in eastern North Carolina resulting in record flood-flow loadings of freshwater and contaminants to Pamlico Sound, North Carolina. The inland flooding, water quality, and loadings to Pamlico Sound were determined as part of a multi-agency response to the floods and in an effort to understand the effects of the floods on the greater Pamlico Sound Basin. All major river basins draining to Pamlico Sound experienced floods at the 500-yr recurrence level. The volume of flood waters entering Pamlico Sound during September–October 1999 was estimated to be equivalent to about 95% of the volume of Pamlico Sound, meaning that flood waters could have essentially displaced most of the water present in Pamlico Sound. Nitrogen and phosphorus loads to the Pamlico River estuary and Neuse River estuary, the two principal estuaries draining to Pamlico Sound, in a 36-d period during the flooding were between 50–90% of the long term average annual loads. Pesticide concentrations in flood waters were surprisingly high, given the amount of dilution produced by the floodwaters. 相似文献
15.
渤海湾西岸全新世沉积速率对河流供给的响应 总被引：2，自引：1，他引：1
渤海湾西岸由北向南获取了3个钻孔,以全新世海相岩心为研究对象,采用AMS14C(Accelerator Mass Spectrometry14C,加速器质谱14C)测年方法建立年代框架并计算平均沉积速率,结合沉积物粒度组成及沿岸古河流三角洲发育历史,探讨了沉积速率对沿岸河流供给变化的时空响应。结果表明,早全新世—中全新世初期(11~6ka),渤海湾西岸整体沉积速率偏低,仅0.03~0.07cm/a,沉积物粒度较粗;中全新世6.43~4.97ka cal BP期间,NP3孔平均沉积速率为0.60~0.93cm/a,高于同期沿岸南部的CH110孔和BT113孔。沉积物组成以粉砂为主,粘土含量低,向上逐渐变粗,具三角洲反粒序特征。该时段的高沉积速率系渤海湾西北岸对潮白河、永定河及滦河沉积物供给的响应;中全新世晚期3.68~2.67ka cal BP期间,BT113孔沉积速率为0.27~1.4cm/a,高于同期沿岸北部CH110孔和NP3孔,沉积物组成以粉砂为主,粘土含量较NP3孔高,向上逐渐变粗,具三角洲反粒序特征。该时段的高沉积速率系渤海湾西岸南部对黄河沉积物供给的响应;晚全新世2.29~0.24ka cal BP期间,沿岸中部CH110孔沉积速率为0.55~0.91cm/a,高于同期沿岸南部的BT113孔和北部的NP3孔,该高沉积速率为渤海湾西岸中部对黄河和海河供给沉积的先后响应。 相似文献
16.
Steven G. Morgan Jennifer L. Fisher Skyli T. McAfee John L. Largier Seth H. Miller Megan M. Sheridan Joseph E. Neigel 《Estuaries and Coasts》2014,37(5):1269-1283
The effectiveness of larval behavior in regulating transport between well-mixed, low-inflow estuaries and coastal waters in seasonally arid climates is poorly known. We determined the flux of an assemblage of benthic crustacean larvae relative to physical conditions between a shallow estuary and coastal waters on the upwelling coast of northern California (38°18′N, 123°03′W) from 29 to 31 March 2006. We detected larval behaviors that regulate transport in adjacent coastal waters and other estuaries for only two taxa in the low-inflow estuary, but they were apparent for taxa outside the estuary. Vertical mixing in the shallow estuary may have overwhelmed larvae of some species, or salinity fluctuations may have been too slight to cue tidal vertical migrations. Nevertheless, all larval stages of species that complete development in nearshore coastal waters were present in the estuary, because they remained low in the water column reducing seaward advection or they were readily exchanged between the estuary and open coast by tidal flows. Weak tidal flows and gravitational circulation at the head of the estuary reduced seaward transport during development for species that completed development nearshore, whereas larval release during nocturnal ebb tides enhanced seaward transport for species that develop offshore. Thus, nonselective tidal processes dominated larval transport for most species back and forth between the low-inflow estuary and open coastal waters, whereas in adjacent open coastal waters, larval behavior in the presence of wind-induced shear was more important in regulating migrations between adult and larval habitats along this upwelling coast. 相似文献
17.
依据深圳沿海所取31件表层海水样品的水化学数据,对主要离子Ca2+、Mg2+、Na+、K+、SO42-和HCO3-与C l-以及B r-与C l-的关系作散点图分析。西海岸表层海水Ca2+、K+、SO42-和HCO3-与C l-的比偏离海水稀释线,源于其位于珠江河道影响范围,与珠江水有不同程度的混合;东海岸表层海水Ca2+、K+和HCO3-与C l-的比主要围绕海水稀释线波动,表明沿海表层海水流动缓慢,受表层海水蒸发和当地沿岸污染河水排泄的长期累积影响;靠近深圳湾的5件西海岸海水样品成分与东海岸表层海水相似。 相似文献
18.
Andreas Kleeberg 《Estuaries and Coasts》1996,19(1):21-30
Presented is a simple mass-balance approach to evaluate the efficiency of dredged sedimentation traps for the elimination of suspended matter and phosphorus (P). Sediment parameters inside and outside the traps were analysed from three river mouths in northern Germany. In the pits, a fine-grained sediment richer in iron, P, and organic content than the surrounding sediment was trapped. However, the sediment P fractionation carried out indicates that no increased release of P is expected, which is not different from those found in natural beds. Hence, these traps are a practicable measure of reducing riverine seston and P discharges to the interior coastal waters and consequently to the open Baltic. *** DIRECT SUPPORT *** A01BY073 00003 相似文献
19.
Charles E. Tilburg Shaun M. Gill Stephan I. Zeeman Amy E. Carlson Timothy W. Arienti Jessica A. Eickhorst Philip O. Yund 《Estuaries and Coasts》2011,34(4):785-799
Interest in the coastal dynamics of river plumes has mainly focused on large rivers, but plumes from the more numerous smaller
rivers have important local consequences and may, in aggregate, be significant contributors to coastal circulation. We studied
the dynamics of the plume from the Saco River in Saco Bay, Gulf of Maine, over a 3-year period. The transport and salinity
in the region are governed by river discharge, tides, winds, and interaction with the Western Maine Coastal Current. The dynamics
of the flow field vary with location within the plume and discharge. The far-field dynamics of the Saco River plume are dominated
by inertial processes (hence qualifying it as a small-scale river plume), during times of low discharge, with low salinity
water present both up and downstream of the river mouth, but are dominated by rotational processes during times of high discharge
(thus qualifying it as a large-scale river plume), with buoyant water primarily advected downshelf. Near-field dynamics are
governed by weak, subcritical flow during low discharge but strongly inertial, supercritical flow during high discharge. Offshore
movement of the plume is not governed by Ekman dynamics but is instead a result of discharge, wind-induced vertical mixing,
and the geography of the coastline and adjacent islands. 相似文献
20.
为了深入认识珠江现代入海物质在粤西陆架随海流迁移扩散的路径和沉积中心,利用Gao-Collins方法分析了粤西-琼东北近海1 515个站位的粒径趋势,并用210Pb法测定了8支柱样的现代沉积速率。结果表明,在粤西沿岸流和南海暖流这两个相向海流的共同作用下,珠江口外珠江来源的泥质沉积物的主体被限制在-50 m等深线以浅的内陆架。现代珠江入海物质能维持粤西陆架泥质沉积区0.1 cm/a左右的现代沉积速率。在川山群岛至海陵岛一带和琼州海峡东侧泥质区,分别受岛屿阻挡和逆时针中尺度涡旋的影响,形成了现代沉积中心。在沉积物不同粒级的来源和搬运方式存在差异的地方,粒径趋势分析结果可能主要反映的是粗颗粒沉积物的运移趋势,而非细颗粒沉积物的运移方向。 相似文献