滇池内湖滨带底泥的有机质分布规律

2008年4月,用自制柱状采泥器及彼德森采泥器在滇池草海和外海采集内湖滨带底泥柱状样(每5 cm分一层)和表层样(0～10 cm).其中,草海内湖滨带底泥表层样12个,柱状样9个;外海内湖滨带底泥表层样22个,柱状样7个.研究结果表明,滇池内湖滨带底泥表层有机质含量为2.20～154.62 g/kg,滇池草海内湖滨带底泥中平均有机质含量为76.94 g/kg,明显高于外海(16.56 g/kg),这主要是因为草海是沼泽化湖湾且附近村落密集;草海内湖滨带底泥有机质含量的最大值出现在西岸,而外海内湖滨带底泥有机质含量也是西岸高于东岸,这主要是由于周围农业和渔业的影响所致.由于外源污染输入量及湖内自净能力等的综合作用逐年波动,使内湖滨带底泥有机质含量垂直分布未明显随深度增加而一直增加或降低.滇池内湖滨带底泥表层pH为7.03～7.96,略偏碱性,外海内湖滨带底泥pH水平略高于草海,底泥含水率除个别采样点外变化不大,多数低于50%.     

抚仙湖-星云湖出流改道工程环境影响分析

抚仙湖、星云湖综合治理出流改道工程旨在“保护抚仙湖、改善星云湖、不影响东风水库水质”，不仅涉及到玉溪市饮用水源的保护和城市水源的长远发展规划，还涉及到东风水库、曲江和海口河至南盘江及其沿岸城市引水工程的防洪度汛，及两湖一库（抚仙湖、星云湖、东风水库）流域的生物多样性保护和自然生态环境保护。因此，工程实施前对工程的主要生态环境影响进行全面的分析非常必要。对工程所涉及到的抚仙湖、星云湖和东风水库的水质、生态效应、生物交流以及流域内的相关用水工程的影响作较为全面的分析，旨在为工程的进一步实施提供决策参考。     

中国云南高原抚仙湖和星云湖水系氮和磷的分布状况和动态变化

2000年11月和2001年6月，通过深入细致的实地调查和分析所收集的样本，对抚仙湖和星云湖水系氮和磷的分布状况与动态变化进行了研究。星云湖的氮磷总量处在一个高浓度状态，并伴随着蓝藻水华的大爆发，而抚仙湖的氮磷总量浓度是星云湖的二十分之一到四十分之一。在雨季，抚仙湖的溶解磷和磷总量随着深度而增加，这暗示着下层滞水带对有机磷微粒活跃的降解作用以及由雨季地表径流增加而带来的大量的土壤矿石的沉积。在已测量和已发表资料的基础上，检查对星云湖和抚仙湖氮磷总量的预测。星云湖大部分外来的磷和氮从一个出口流出，但是估计进入抚仙湖97％的磷和25％的氮被埋藏在沉积物里。反硝化作用可能是抚仙湖中余留总氮耗损的原因。减少来自汇流区的总氮和总磷负荷是保护星云湖和抚仙湖所必不可少的。     

洪泽湖生态补偿多元化探索

洪泽湖是我国第四大淡水湖,目前洪泽湖的湿地保护主要由政府主导的生态补偿,但由于政府的财政支持缺口巨大,拓展洪泽湖湿地生态补偿资金的来源渠道是保障洪泽湖可持续发展的坚实基础。本研究聚焦洪泽湖生态补偿需求,提出协调多方保护主体以构建洪泽湖生态保护联盟,强化流域一体化治理,推动基于生态“洪泽湖”品牌的渔业产业升级,构建旅游生态补偿机制反哺洪泽湖湿地的保护策略,推进洪泽湖湿地碳汇潜力与湿地银行建设,自下而上推动洪泽湖生态补偿多元化。洪泽湖生态补偿模式的多元化发展依赖于顶层制度的建设与本土化策略的双向互动,共同实现洪泽湖湿地的生态价值的商品化与市场化。     

青海可可西里东北部多秀湖和盐湖水化学特征研究

2016年3月系统采集了青海可可西里东北部多秀湖和盐湖的湖水及其入湖冰川融水。研究发现,两个湖泊湖水中离子含量均较高,主要阳离子含量顺序均为Na~+Mg~(2+)K~+Ca~(2+),主要阴离子含量顺序均为Cl~-SO_4~(2-)HCO_3~-CO_3~(2-);而入湖冰川融水的离子含量非常低。根据库尔纳可夫—瓦良什科水化学分类标准,多秀湖湖水属于硫酸盐型—硫酸镁亚型,盐湖湖水属于硫酸盐型—硫酸钠亚型。多秀湖和盐湖湖水Li—Mg—B的相关性均为正相关,说明两个湖泊中这3种元素的物质来源、搬运条件及富集环境具有很强的相似性。由于气候变暖导致大量矿化度低的冰川融水注入盐湖,矿化度较低的卓乃湖和库赛湖决堤湖水泄入盐湖,使得盐湖的面积较1997年扩大了5倍,湖水的矿化度降低了约10倍,而多秀湖近些年湖水矿化度变化较小。多秀湖湖水矿化度以及Li~+、Mg~(2+)和B_2O_3含量均较高,具有较好的资源潜在利用价值。     

洞庭湖演变趋势探讨

洞庭湖的演变主要受构造沉降、泥沙淤积和人类活动影响三大因素的控制。目前 ,洞庭湖盆的构造沉降速率虽然较低 (3～ 10mm/a) ,但构造沉降量仍抵消了部分泥沙淤积量 ,在一定程度上抑制了洞庭湖日益萎缩的趋势。由于湖盆中泥沙淤积速率大于构造沉降速率 ,洲滩会继续发育和扩展 ,洞庭湖仍保持淤高的趋势。在“4 35 0工程”完成和三峡建坝后 80年内 ,湖盆泥沙淤积速率将降低到 1 79mm/a ,洞庭湖不断淤高的趋势将得到减缓。     

新疆玛纳斯湖变迁的气候和构造分析

在卫星影像分析、野外调查的基础上,结合前人研究的资料研究,玛纳斯湖的气候演化背景和区域构造活动背景。然后从玛纳斯湖水面高低和空间位置两个方面讨论玛纳斯湖的演化历史。指出第四纪以来玛纳斯湖出现6次高湖面,经历古玛纳斯湖向北迁移-古玛纳斯湖盆形成-退缩-解体-衰竭的演化过程。     

A late Lake Minong transgression in the Lake Superior basin as documented by sediments from Fenton Lake, Ontario

The evolution of the early Great Lakes was driven by changing ice sheet geometry, meltwater influx, variable climate, and isostatic rebound. Unfortunately none of these factors are fully understood. Sediment cores from Fenton Lake and other sites in the Lake Superior basin have been used to document constantly falling water levels in glacial Lake Minong between 9,000 and 10,600 cal (8.1–9.5 ka) BP. Over three meters of previously unrecovered sediment from Fenton Lake detail a more complex lake level history than formerly realized, and consists of an early regression, transgression, and final regression. The initial regression is documented by a transition from gray, clayey silt to black sapropelic silt. The transgression is recorded by an abrupt return to gray sand and silt, and dates between 9,000 and 9,500 cal (8.1–8.6 ka) BP. The transgression could be the result of increased discharge from Lake Agassiz overflow or the Laurentide Ice Sheet, and hydraulic damming at the Lake Minong outlet. Alternatively ice advance in northern Ontario may have blocked an unrecognized low level northern outlet to glacial Lake Ojibway, which switched Lake Minong overflow back to the Lake Huron basin and raised lake levels. Multiple sites in the Lake Huron and Michigan basins suggest increased meltwater discharges occurred around the time of the transgression in Lake Minong, suggesting a possible linkage. The final regression in Fenton Lake is documented by a return to black sapropelic silt, which coincides with varve cessation in the Superior basin when Lake Agassiz overflow and glacial meltwater was diverted to glacial Lake Ojibway in northern Ontario.     

青藏高原北部孢粉记录的全新世以来环境变化

根据青藏高原北部同纬度地区,同一个垂直自然带内的西藏羊湖的湖相沉积、青海昆仑河河流相沉积、青海豆错(苦海)湖的湖相沉积记录的全新世以来孢粉(spore-pollen)资料的对比分析,表明:①极度干旱荒漠区的代表植被麻黄属(Ephedra)花粉平均百分含量,三个地区分别为:7.7%,4.2%,7.5%,总体上,羊湖地区的数值高于昆仑河地区与苦海地区。②代表气候湿润的禾本科(Gram ineae)花粉平均百分含量,三个地区分别为:1.2%、4.9%、12.0%,从西向东数值逐渐升高。③代表气候湿润的蒿属(Artem isia)花粉平均百分含量,三个地区分别为:22.2%,43.6%,48.8%,从西向东数值逐渐升高。④代表气候干旱的藜科(Chenopod iaceae)花粉平均百分含量,三个地区分别为:52.1%,42.4%,11.5%,从西向东数值逐渐降低。⑤依据蒿属、藜科花粉百分含量,计算出环境变化指标,蒿属/藜科(A/C)值,三个地区的平均值分别为:0.45,1.23,5.59,从西向东比值逐渐升高,⑥麻黄属/蒿属值,在全新世晚期,三个地区都呈上升趋势,但幅度存在差异,分别为:0.45,0.34,0.28,从西向东数值逐渐降低。综观上述6个方面的变化规律,青藏高原北部全新世以来,干旱的程度从西向东逐渐降低;对青藏高原北部东西方向现今植被和环境的实际考察并结合上述变化规律,未来高原北部干旱变化的趋势将继续由西向东推移。     

基于RS和GIS技术的库木库勒盆地盐湖面积变化与气候响应关系

利用Landsat卫星1972-2013年间五个时期的遥感影像数据为基础,结合野外实际调查和室内解译分析,运用RS和GIS技术,提取影像中盐湖湖水边界信息,并绘制了五个时期盐湖面积变化的图谱。并结合库木库勒盆地气象数据（年降水量、平均气温、相对湿度、平均风速）对盐湖面积变化进行响应分析,探究盐湖变化与气候之间的相关性,并讨论气候变化对库木库勒盆地地区内盐湖面积变化的影响机制,分析不同气象因子对盆地内盐湖面积变化的作用。得出平均气温、降水量、相对湿度对盆地内盐湖的面积扩大均有促进作用,而且平均气温的作用占主导性的,这为库木库勒盆地盐湖的演化以及盐湖资源开发提供相应参考和借鉴意义。     

Big lake records preserved in a little lake’s sediment: an example from Silver Lake,Michigan, USA

We reconstruct postglacial lake-level history within the Lake Michigan basin using soil stratigraphy, ground-penetrating radar (GPR), sedimentology and ¹⁴C data from the Silver Lake basin, which lies adjacent to Lake Michigan. Stratigraphy in nine vibracores recovered from the floor of Silver Lake appears to reflect fluctuation of water levels in the Lake Michigan basin. Aeolian activity within the study area from 3,000 years (cal yr. B.P.) to the present was inferred from analysis of buried soils, an aerial photograph sequence, and GPR. Sediments in and around Silver Lake appear to contain a paleoenvironmental record that spans the entire post-glacial history of the Lake Michigan basin. We suggest that (1) a pre-Nipissing rather than a Nipissing barrier separated Silver Lake basin from the Lake Michigan basin, (2) that the Nipissing transgression elevated the water table in the Silver Lake basin about 6,500 cal yr. B.P., resulting in reestablishment of a lake within the basin, and (3) that recent dune migration into Silver Lake is associated with levels of Lake Michigan. This is the fourth in a series of ten papers published in this special issue of Journal of Paleolimnology. These papers were presented at the 47th Annual Meeting of the International Association for Great Lakes Research (2004), held at the University of Waterloo, Waterloo, Ontario, Canada. P.F. Karrow and C.F.M. Lewis were guest editors of this special issue.     

构造沉降和泥沙淤积对洞庭湖区防洪的影响

作者利用洞庭盆地多年水准测量资料和洞庭湖近年的泥沙资料,对洞庭盆地的构造沉降速率和泥沙淤积速率进行了分析,从地貌学和水利学角度,对“洞庭湖盆”和“洞庭盆地”这两个不同的空间概念进行了区分,在此基础上,探讨了构造沉降和泥沙淤积对洞庭湖蓄洪空间和防洪大堤的影响。在目前洞庭湖盆被大堤围限的情况下,洞庭盆地的构造沉降运动使洞庭湖的蓄洪空间不断减小;洞庭盆地的构造沉降量虽然在一定程度上缓解了洞庭湖不断萎缩的趋势,但构造沉降对洞庭湖区的防洪形势却是不利的。构造沉降和泥沙淤积均对防洪大堤的质量提出了更高的要求,增大了洞庭湖区防洪的难度。     

可可西里地区库赛湖变化及湖水外溢成因

以库赛湖研究区地形图、Landsat TM/ETM+和中国环境与灾害监测预报卫星HJ1A/BCCD影像为基础,结合五道梁气象站气温降水资料,利用地理信息技术和数理统计方法,对2011 年9 月可可西里地区库赛湖湖水外溢成因进行分析。结果表明,库赛湖湖水外溢发生在2011 年9 月20 日至30 日期间,卓乃湖湖水进入库赛湖是后者发生变化的直接原因,而库赛湖规模近20 年来的持续增长,尤其是2006 年之后湖泊面积快速增加是其湖水外溢的基础。卓乃湖湖水外泄的主要诱因是区域持续降水,其中8 月17 日和21 日强降水使卓乃湖于8 月22 日出现漫顶溢流,8 月31 日至9 月5 日、9 月16 日至17 日期间两次持续降水导致卓乃湖水量剧增,并在9 月14 日至21 日期间形成洪水。由于水量外泄,卓乃湖面积骤降,截至11 月29 日,湖泊面积168.07 km²,仅为8 月22 日湖泊面积的62%,共减少104.88 km²。库赛湖外溢湖水流入海丁诺尔后又进入盐湖,其中海丁诺尔湖水进入盐湖时间介于10 月6 日至20 日期间。外来湖水大量进入导致海丁诺尔和盐湖在10-11月份快速扩大。     

Reconstruction of glacial Lake Hind in southwestern Manitoba, Canada

Glacial Lake Hind was a 4000 km² ice-marginal lake which formed in southwestern Manitoba during the last deglaciation. It received meltwater from western Manitoba, Saskatchewan, and North Dakota via at least 10 channels, and discharged into glacial Lake Agassiz through the Pembina Spillway. During the early stage of deglaciation in southwestern Manitoba, part of the glacial Lake Hind basin was occupied by glacial Lake Souris which extended into the area from North Dakota. Sediments in the Lake Hind basin consist of deltaic gravels, lacustrine sand, and clayey silt. Much of the uppermost lacustrine sand in the central part of the basin has been reworked into aeolian dunes. No beaches have been recognized in the basin. Around the margins, clayey silt occurs up to a modern elevation of 457 m, and fluvio-deltaic gravels occur at 434–462 m. There are a total of 12 deltas, which can be divided into 3 groups based on elevation of their surfaces: (1) above 450 m along the eastern edge of the basin and in the narrow southern end; (2) between 450 and 442 m at the western edge of the basin; and (3) below 442 m. The earliest stage of glacial Lake Hind began shortly after 12 ka, as a small lake formed between the Souris and Red River lobes in southwestern Manitoba. Two deltas at an elevation of 450 were formed in this lake. At the same time, the Souris Lobe retreated far enough to allow glacial Lake Souris to expand farther north along the western side of the basin from North Dakota into what was to become glacial Lake Hind. Three deltas were built at an elevation above 460 m in the Canadian part of this proglacial lake. Continued ice retreat allowed the merger of glacial Lake Souris with the interlobate glacial Lake Hind to the east. Subsequent erosion of the outlet to the Pembina Spillway allowed waters in the glacial Lake Hind basin to become isolated from glacial Lake Souris, and a new level of glacial Lake Hind was established at 442 m, with 5 deltas built at this level by meltwater runoff from the west. Next, a catastrophic flood from the Moose Mountain uplands in southeastern Saskatchewan flowed through the Souris River valley to glacial Lake Souris, spilling into Lake Hind and depositing another delta. This resulted in further incision of the outlet (Pembina Spillway). A second flood through the Souris Spillway from glacial Lake Regina further eroded the outlet; most of glacial Lake Hind was drained at this time except for the deeper northern part. Coarse gravel was deposited by this flood, which differs from previous flood gravel because it is massive and contains less shale.     

12 600 years of lake level changes, changing sills, ephemeral lakes and Niagara Gorge erosion in the Niagara Peninsula and Eastern Lake Erie basin

Over the last 12600 years, lake levels in the eastern Lake Erie basin have fluctuated dramatically, causing major changes in drainage patterns, flooding and draining ephemeral Lake Wainfleet several times and widening and narrowing the Niagara Gorge as the erosive effects of Niagara Falls waxed and waned. The control sill for Lake Erie levels was at first the Fort Erie/Buffalo sill, before the Lyell/Johnson sill in Niagara Falls took over due to isostatic rebound. This sill, in time, was eventually eroded by the recession of Niagara Falls and the Fort Erie/Buffalo sill regained control. The environmental picture is complicated by catastrophic outbursts from glacial Lake Agassiz and Lake Barlow-Ojibway, changes in outlet routes, isostatic rebound and climatic changes over the Great Lakes basins. Today, the flow of water into Lake Erie from the streams and rivers surrounding it only accounts for about 13% of the flow out of it, therefore, the importance of flow from the Upper Great Lakes, specifically the flow from Lake Huron, has a great effect on Lake Erie levels. While the changing control sills, Lyell/Johnson and Buffalo/Fort Erie would affect Lake Erie levels, overall they are mostly input driven by the amount of waters received from the Upper Great Lakes. Since Lake Erie's water level changes are so closely tied to Lake Huron's water level changes we have decided to use names assigned to Lake Huron such as the two Mattawa highstands and three Stanley lowstands rather than inflict a whole new set of names on the public. While the duration of each high and lowstand in Erie and Huron may not always be the same, they always happen within the same time frame. The datum elevations used for Lake Huron (175.8 m) and Lake Erie (173.3 m) are historically recorded averages. The Lake Erie levels proposed in this paper reflect Lake Hurons effects on Lake Erie and the levels occuring at the eastern end of the Erie Basin throughout the last 12600 years. All dates in this paper are uncorrected ¹⁴ C dates unless the date was obtained from shells, then the date has been corrected for hard-water effects. Also, all heights are given as modern day elevations and are not adjusted for isostatic rebound.     

Late Pleistocene and Holocene lake fluctuations in the Sevier Lake basin,Utah, USA

Sevier Lake is the modern lake in the topographically closed Sevier Lake basin, and is fed primarily by the Sevier River. During the last 12 000 years, the Beaver River also was a major tributary to the lake. Lake Bonneville occupied the Sevier Desert until late in its regressive phase when it dropped to the Old River Bed threshold, which is the low point on the drainage divide between the Sevier Lake basin and the Great Salt Lake basin. Lake Gunnison, a shallow freshwater lake at 1390 m in the Sevier Desert, overflowed continuously from about 12 000 to 10 000 yr B.P., into the saline lake in the Great Salt Lake basin, which continued to contract. This contrast in hydrologic histories between the two basins may have been caused by a northward shift of monsoon circulation into the Sevier Lake basin, but not as far north as the Great Salt Lake basin. Increased summer precipitation and cloudiness could have kept the Sevier Lake basin relatively wet.By shortly after 10 000 yr B.P. Lake Gunnison had stopped overflowing and the Sevier and Beaver Rivers had begun depositing fine-grained alluvium across the lake bed. Sevier Lake remained at an altitude below 1381 m during the early and middle Holocene. Between 3000 and 2000 yr B.P. the lake expanded slightly to an altitude of about 1382.3 m. A second expansion, probably in the last 500 years, culminated at about 1379.8 m. In the mid 1800s the lake had a surface altitude of 1379.5 m. Sevier Lake was essentially dry (1376 m) from 1880 until 1982. In 1984–1985 the lake expanded to a 20th-century high of 1378.9 m in response to abnormally high snow-melt runoff in the Sevier River. The late Holocene high stands of Sevier Lake were most likely related to increased precipitation derived from westerly air masses.This is the first of a series of papers to be published by this journal that was presented in the paleolimnology sessions organized by R. B. Davis and H. Löffler for the XIIth Congress of the International Union for Quaternary Research (INQUA), which took place in Ottawa, Canada in August 1987. Drs. Davis and Löffler are serving as guest editors of this series.     

西太湖沉积物污染的地球化学记录及对比研究

通过对西太湖MS、DLS沉积短岩芯中金属元素、营养指标的对比分析,讨论了西太湖近80年来的元素地球化学演化特征。结果表明,20世纪40年代以前,西太湖沉积物中元素为自然来源;40~70年代末期,除北部Hg、TP受到人为污染之外,其余元素仍主要为自然来源;70年代末期以来,重金属元素人为污染逐渐加重,湖泊营养程度升高。西太湖北部沉积物中Pb、Zn、Mn、Ni、As污染开始于20世纪70年代末期,Hg污染开始于40年代初期;与北部相比,南部沉积物重金属污染历史较短,Pb、Zn污染开始于70年代末期,As、Mn、Ni、Hg污染开始于80年代中期~末期。西太湖北部、南部沉积物中TN、TOC含量70年代末期以来开始增加,C/N比值增大,有机质外源输入比例增加。西太湖北部沉积物中TP含量自40年代初期以来逐渐增加,受到人为污染;南部TP含量在40~70年代略高,但无明显的人为污染特征。     

Late‐Summer Peak in Sediment Accumulation in Two Lakes with Contrasting Watersheds,Alaska

The timing of clastic sedimentation in two glacial‐fed lakes with contrasting watersheds was monitored using sequencing sediment traps for two consecutive years at Allison Lake (Chugach Range, Alaska) and four months at Shainin Lake (Brooks Range, Alaska). Shainin Lake is a weakly stratified lake fed by distant glaciers, whereas Allison Lake is more strongly stratified and fed predominantly by proximal glaciers. At Shainin Lake, sediment accumulation started in late June and reached its maximum in mid‐August, just before lake mixing and during a period of low river discharge. The grain size of the sediment reaching the sediment trap in Shainin Lake was homogenous throughout the summer. At Allison Lake, pulsed sedimentation of coarse particles during late summer and early fall storms were superimposed on the fine‐grained sedimentation pattern similar to that observed at Shainin Lake. These storms triggered underflows that were observed in the thermal structure of the lake and deposited abundant sediment. The sequencing sediment traps reveal a lag between fluvial discharge and sediment deposition at both lakes, implying limitations to interpreting intra‐annual sedimentary features in terms of inflow discharge.     

博斯腾湖环境变化及其与焉耆盆地[2]绿洲开发关系研究

文章从自然和人类活动两方面分析了自1958年以来博斯腾湖环境变化。认为：近40年来，自然因素对湖水位变化的影响力要大于人为活动对湖水位变化的贡献，绿洲开发引起的入湖水量减少和大量的高矿化度农田排水排入湖区使博斯腾湖迅速演变为微咸湖，控制着博斯腾湖水化学类型的变化和形成。在此基础上，探讨了博斯腾湖环境变化与焉耆盆地绿洲开发和绿洲环境变化相互作用的机理，指出尽管近10几年来绿洲环境的发展是可持续的，但整个焉耆盆地环境持续发展关键在于控制绿洲开发利用规模。适宜的绿洲发展规模，可保证绿洲环境和博斯腾湖环境的可持续发展。     

博斯腾湖环境变化及其与焉耆盆地绿洲开发关系研究

章从自然和人类活动两方面分析了自1958年以来博斯腾湖环境变化。认为：近40年来，自然因素对湖水位变化的影响要大于人为活动对湖水位变化的贡献，绿洲开发引起的入湖水量减少和大量的高矿化度农田排水排入湖区使得博斯腾湖区迅速演变为微咸湖，控制着博斯腾湖水化学类型的变化和形成。在此基础上，探讨了博斯腾湖环境变化与恶焉煮盆地绿洲开发和绿洲环境变化相互作用的机理，指出尽管近10几年来绿洲环境的发展是可持续的，但整个焉耆盆地环境持续发展关键在于控制绿洲开发利用规模。适宜的绿洲发展规模，可保证绿洲环境和博斯腾湖环境的可持续发展。