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1.
巢湖水系位于长江中下游左岸,主体处于安徽省中部。流域西北以江淮分水岭为界,东濒长江,南与菜子湖、白荡湖、陈瑶湖以皖河流域毗邻。呈东西长、南北窄状分布。流域总面积13486平方千米(含铜城闸以下牛屯河流域404平方千米),约占安徽省总面积的9.3%。其中,巢湖闸以上9153平方千米,巢湖闸以下4333平方千米。主要包括合肥、巢湖、六安及安庆4市的16个县区。该水系主要支流发源于大别山区,自西向东流注,经巢湖,由裕溪河(及裕溪河支流牛屯河)进入长江。以巢湖为中心,四周河流呈放射状注入。较大支流有  相似文献   

2.
环太湖河道水质分析与入湖污染物负荷量估算   总被引:3,自引:0,他引:3  
以环太湖河道的河口 (临太湖 )点位为对象 ,通过非参数检验探讨太湖地区河道水质时空差异。对无锡地区进行入湖河道污染负荷量研究 ,确认污染现状与总量控制目标间存在差距。研究还表明 ,总磷污染最为严重 ,对太湖 (太湖的西 -西北 -北部分 )水体富营养化影响最大的入湖河道有直湖港、太鬲运河、漕桥河、太鬲南运河和大浦港。  相似文献   

3.
环太湖河道水质分析与入湖污染物负荷量估算   总被引:21,自引:0,他引:21  
以环太湖河道的河口(临太湖)点位为对象,通过非参数检验探讨太湖地区河道水质时空差异。对无锡地区进行入湖河道污染负荷量研究,确认污染现状与总量控制目标间存在差距。研究还表明,总磷污染最为严重,对太湖(太湖的西-西北-北部分)水体富营养化影响最大的入湖河道有直湖港、太鬲运河、漕桥河、太鬲南运河和大浦港。  相似文献   

4.
梁国昭 《热带地理》1998,18(1):18-23
经70年代的建设,德国的美因-多瑙运河于1992年建成通航。虽然德国国内对这一宏大的工程颅有争议,但工程建设中有不少经验可供我国参考。我国已规划在21世纪兴连接长江水系和珠江水系的湘桂运河和粤赣运河。规划的湘桂运河位于古灵渠附近;粤赣运河位于广东南雄和江西信丰之间。建设这两条运河的天然条件均优于美国-多瑙运河。为保护漓江山水资源,建议重新考虑湘桂运河的位置,提出在广西富川和湖南江化之间选址。  相似文献   

5.
尕斯库勒湖流域所属行政区茫崖市自建市以来尚未建设较大规模的集中供水水源,在以水定产、以水定城的城市发展构架下,评价流域地下水资源及开采潜力对城市发展至关重要。文章基于资料收集、动态长观、钻孔抽水试验等手段,采用断面径流量法结合流域尺度的数值模拟,评价了区内地下水天然资源量和允许开采量,并对地下水开采后对水文环境的影响进行了评估。结果表明:尕斯库勒湖流域地下水天然资源量为 98.82×104m3/d,允许开采量为 23.5×104m3/d,地下水资源开采系数 <0.4,开采程度低;开采稳定后下游泉水减少 10.89×104m3/d,蒸发量减少 12.88×104m3/d,开采量和泉水及蒸发量减少之和相等,开采地下水间接袭夺了无效蒸发和部分泉水;下游湿地区降深≤0.5 m,湿地面积不产生退化;尕斯库勒湖入湖量减少 2.53×104m3/d,能维持湖泊及湿地周围生态环境的良性循环。  相似文献   

6.
近60年洞庭湖泊形态与水沙过程的互动响应   总被引:2,自引:0,他引:2  
以历史文献、图件及1951~2009年长系水沙等资料为依据,对比分析洞庭湖形态与水沙过程的互动响应,结果表明:由于湖泊形态与水沙过程存在着相互作用的关系,近60年间,水沙过程以多种形式改变湖泊形态特征值,如湖盆结构破碎、解体,水深变浅以及湖面﹑湖容依次减少1840km2及130×108m3;同时湖泊形态特征值改变也引起水沙特性变异,在1951~2002年间湖盆蓄水量呈明显的增减波动,但同流量下汛期水位普遍抬高1.2~1.90m,西﹑南﹑东洞庭湖水位变幅依次增大1.61m、1.39m和1.35m,各主要水文站前5位最高洪水位排序的年份均出现在湖面积(容积)历史最低值,泥沙淤积率为70%以上;2003年6月三峡水库蓄水及"退田还湖"后,高、中水位下湖盆调蓄量有所减少,城陵矶丰、枯水位分别降低1.12m及0.35m,西湖区与东南湖区的泥沙输出比均呈增大趋势,泥沙淤积率减至35.9%。其互动响应机制,可概化为泥沙淤积循环→湖盆结构破碎、解体,湖面湖容缩小→水沙特性异变→改变湖泊形态→水沙特性变异的互动响应动态演进模式。  相似文献   

7.
选取伊犁河谷为研究区,探讨了夏朝以来的1 029处遗址时空分布和地理背景。结果表明:遗址分布的地貌类型依次为“河岸阶地→河流谷地、谷地的丘陵和高阶地→低起伏低山和低丘陵→冲(洪)积平原、河谷平原”。遗址分布范围分别经历了“分散”、“扩大”、“收敛”、“集中”的演变,其空间格局由前3个时期的“东高西低”演变为后3个时期的“西高东低”,其分布中心经历了从河流“中上游→下游”的演变。遗址集中分布于第2~8级(601~1 300 m)高程和第1~5级坡度(0~9°),且随着时间的推移,其表现出从高海拔、高坡度向低海拔、低坡度转移的趋势。古遗址数量、规模均以宋元明时期最高,而古墓葬则以春秋-秦时期居首。古墓葬遗址主导文化经历了“安德罗诺沃文化→索墩布拉克文化→乌孙文化”的演变过程。  相似文献   

8.
艾比湖近期入湖水量及其变化   总被引:4,自引:2,他引:4  
1988年对文比湖进行环湖考察,结果表明艾比湖入湖地表径流来自博尔塔拉河和精河.从1988年6月~1993年12月设站观测两河入湖水量,1989~1993年平均入湖水量4.64×108m3,其中博尔塔拉河入湖水量3.31×108m3,占71.3%;精河为1.33×108m3,占28.7%.在观测的五年中,水量多年变化不大,总入湖水量最大水年与最小水年信比为1.6.两河入湖水量的年内分配不同,博尔塔拉河入湖水量集中在冬季,其原因是博尔塔拉各地有三个断陷盆地,形成三个地下水库,对径流进行调节,使下游丰水期滞后半年.精河入湖水量集中在夏季.两河入湖水量丰、枯水期相互错开,使总太湖水量年内分配均匀.  相似文献   

9.
朱燕 《地理教学》2011,(9):17-18
教学设计思路“长江”一节教材包括“我国第一大河”、“黄金水道”两大部分内容。“我国的第一大河”介绍了长江源远流长、水系庞大、流域广阔、水量丰富的自然特点。描述了长江上、中、下游各段的特征及因地制宜地开发与治理。“黄金水道”介绍了长江具有优越的天然航道和巨大的航运价值,在我国经济建设中的重要地位。  相似文献   

10.
新疆艾比湖流域水资源利用与艾比湖演变   总被引:12,自引:4,他引:8  
本文在综述艾比湖流域自然条件和自然分区、评价流域水资源(包括降水,地表水及地下水)的时空分布及流域经济发展现状的基础上,对水资源的承载能力作了平衡计算,包括农业、工业、城市及生活需水量以及输入艾比湖的水量。计算成果可供编制流域开发的长远规划参考。根据流域不同部位的水热条件,生态环境已存在及潜在的问题,对流域内不同部位的自然资源合理利用途径及生态环境的改善措施,分别提出了方向性的建议意见,例如山区可利用降水多的优势增加自然植被,大风通道可利用风力提水灌溉保证形成良好植被. 对艾比湖演变过程及演变原因,除分析入湖流量变化及湖的水量平衡外,考察了湖岸阶地分布,分析了历史资料及人类活动的影响,并对湖域演变造成的生态环境(如裸露的湖底正处于大风通道上)问题.作了分析和预测.艾比湖今后的演变是大家关心的问题,根据博尔塔拉河和精河径流量的年内分布(主要分析径流集中度集中期)特点,湖盆所处的低洼部位,有利的水文地质条件,予测今后相当长时期,只要有适当的保护措施,水域保持于500km~2左右是可能的. 在分析自然条件特点和生态环境问题的基础上,对流域及湖周地区生态系统的结构,阿拉山口大风及人类活动对生态环境的影响等问题,都作了专题性的深入分析,提出了改善生态环境的综合措施,特别是大风通道及湖岸地区。最后附有流域主要测站的流量、降水、蒸发等实测资料,作为基础数据可供广泛应用参考.  相似文献   

11.
Along the north bank of the Xuxi River, the sand-intercalated-muddy gravel layer from -3.7~-5.8 m in the borehole 7508 at the East Dam and the middle, coarse and fine sand layer with a thickness of 4.5 m at the lower part of the borehole 8179 between the East Dam and the West Dam indicate that a large natural river was here before the Kingdom of Wu excavated the Xuxi Canal. The existence of Neolithic sites such as Xuecheng, Chaoduntou and Xiajiadang along the Xuxi River and the silt layer with dozens of meters archived under the earth's surface within a range of 1 km along both banks are the even more important evidences for the existence of the ancient Zhongjiang River. The floodgate of the East Dam nowadays makes against the communication between the Shuiyangjiang River and the Taihu Lake. The authors suggest the canal between Wuhu and Taihu Lake should be excavated as soon as possible, namely, the navigation channel from Wuhu through Guchenghu Lake, Xuxi River, East Dam, Liyang, Yixing to Taihu Lake should be further widen and the deposits composed of slope wash on the watershed between Shuiyangjiang River and Taihu Lake should be dredged away. Then, the channel journey can be shortened, the boats in ship transportation on the Yangtze River can be shunted to ensure the security of shipping, the resources of sand and gravel in the old river channel can be exploited and the dike of the Yangtze River can be reinforced. So, the problems of irrigation, flood diversion, pollution abatement and drainage of flooded fields in the lower Yangtze River will be resolved. Then, the above methods can impel the sustainable development of the Xuxi River and Taihu Lake area.  相似文献   

12.
Along the north bank of the Xuxi River, the sand-intercalated-muddy gravel layer from -3.7 - -5.8 m in the borehole 7508 at the East Dam and the middle, coarse and fine sand layer with a thickness of 4.5 m at the lower part of the borehole 8179 between the East Dam and the West Dam indicate that a large natural river was here before the Kingdom of Wu excavated the Xuxi Canal. The existence of Neolithic sites such as Xuecheng, Chaoduntou and Xiajiadang along the Xuxi River and the silt layer with dozens of meters archived under the earth's surface within a range of 1 km along both banks are the even more important evidences for the existence of the ancient Zhongjiang River. The floodgate of the East Dam nowadays makes against the communication between the Shuiyangjiang River and the Taihu Lake. The authors suggest the canal between Wuhu and Taihu Lake should be excavated as soon as possible, namely, the navigation channel from Wuhu through Guchenghu Lake, Xuxi River, East Dam, Liyang, Yixing to Taihu Lake should be further widen and the deposits composed of slope wash on the watershed between Shuiyangjiang River and Taihu Lake should be dredged away. Then, the channel journey can be shortened, the boats in ship transportation on the Yangtze River can be shunted to ensure the security of shipping, the resources of sand and gravel in the old river channel can be exploited and the dike of the Yangtze River can be reinforced. So, the problems of irrigation, flood diversion, pollution abatement and drainage of flooded fields in the lower Yangtze River will be resolved. Then, the above methods can impel the sustainable development of the Xuxi River and Taihu Lake area.  相似文献   

13.
The Dongting Lake is located in the south beach of the middle reaches of the Yangtze River. Its catchment, with an area of 262,823 km2 or about 12% of the total Yangtze River catchment, is situated between 28o43?29o32扤 and 112o54?113o8扙, and crosses Hubei and Hunan provinces in administrative division. The main tributaries include Xiangjiang, Zishui, Yuanjiang, Lishui rivers (4 Tributaries) and some local rivers, such as Miluo River, Xinqiang River and other little streams. In the nor…  相似文献   

14.
The sediments of the Dongting Lake come from four channels (one of them was closed in 1959), connected with the Yangtze River, four tributaries (Lishui, Yuanjiang, Zishui and Xiangjiang) and local area, and some of them are transported into the Yangtze River in Chenglingji, which is located at the exit of the Dongting Lake, some of them deposit into drainage system in the lake region and the rest deposit into the lake. The annual mean sediment is 166,555x104 t, of which 80% come from the four channels, 18% from the four tributaries and 2% from local area, whereas 26% of the total sediments are transported into the Yangtze River and 74% deposited into the lake and the lake drainage system. Based on topographic maps of 1974, 1988 and 1998, and the spatial analysis method with geographic information system (GIS), changes in sediment deposition and erosion are studied in this paper. By overlay analysis of 1974 and 1988, 1988 and 1998, erosion and sediments deposition areas are defined. The main conclusions are: (1) sediment rate in the lake is larger than erosion rate from 1974 to 1998. The mean deposition in the lake is 0.43 m; (2) annual sediment deposition is the same between 1974-1988 and 1988-1998, but the annual volume of deposition and erosion of 1988-1998 is bigger than that in 1974-1988; (3) before the completion of the Three Gorges Reservoir, there will be 7.82x108 m3 of sediments deposited in the lake, which would make the lake silted up by 0.33 m; (4) in the lake, the deposition area is found in the north of the east Dongting Lake, the south-west of the south Dongting Lake, and the east of the west Dongting Lake; while the eroded area is in the south of the east Dongting Lake, the middle of the south Dongting Lake, the west of the west Dongting Lake, as well as Xiangjiang and Lishui river flood channels.  相似文献   

15.
Cosmogenic surface exposure ages of glacial boulders deposited in ice-marginal Lake Musselshell suggest that the lake existed between 20 and 11.5 ka during the Late Wisconsin glacial stage (MIS 2), rather than during the Late Illinoian stage (MIS 6) as traditionally thought. The altitude of the highest ice-rafted boulders and the lowest passes on the modern divide indicate that glacial lake water in the Musselshell River basin reached at least 920–930 m above sea level and generally remained below 940 m. Exposures of rhythmically bedded silt and fine sand indicate that Lake Musselshell is best described as a slackwater system, in which the ice-dammed Missouri and Musselshell Rivers rose and fell progressively throughout the existence of the lake rather than establishing a lake surface with a stable elevation. The absence of varves, deltas and shorelines also implies an unstable lake. The changing volume of the lake implies that the Laurentide ice sheet was not stable at its southernmost position in central Montana. A continuous sequence of alternating slackwater lake sediment and lacustrine sheetflood deposits indicates that at least three advances of the Laurentide ice sheet occurred in central Montana between 20 and 11.5 ka. Between each advance, it appears that Lake Musselshell drained to the north and formed two outlet channels that are now occupied by extremely underfit streams. A third outlet formed when the water in Lake Musselshell fully breached the Larb Hills, resulting in the final drainage of the lake. The channel through the Larb Hills is now occupied by the Missouri River, implying that the present Missouri River channel east of the Musselshell River confluence was not created until the Late Wisconsin, possibly as late as 11.5 ka.  相似文献   

16.
长江江苏段末次盛冰期古河槽特征   总被引:1,自引:0,他引:1  
选择长江江苏段作为研究河段,根据南京长江三桥、长江大桥、长江四桥、润扬长江大桥、扬中长江大桥、江阴长江大桥、苏通长江大桥7个断面的285个地质勘探钻孔资料及参考文献中的8个钻孔资料,建立了7个长江古河谷地质剖面图。在拟建南京长江四桥附近、扬中长江大桥附近的7个钻孔进行了采样分析,获得了8个14C年代、1个ESR年代数据。通过分析发现,末次盛冰期长江古河槽镇江以上切割到基岩,镇江以下嵌在老河床相沉积层上,河槽在南京下关-栖霞山段形成局部深切;南京段约-63 m以下的河槽为末次盛冰期的古河槽,相对狭窄陡峭,宽深比较小,向下游宽深比逐渐变大,扬中以下形成分叉河道体系;古河槽中自下而上充填了从粗到细的沉积旋回,河床相沉积物向下游逐渐变细。  相似文献   

17.
The stratigraphical cross-sections of the Yangtze River incised-valley near the No.1,No.3 and No.4 Nanjing Yangtze River bridges were established with respective bore date and documents.By 14C age analysis of the samples of four drilling cores near the No.4 Bridge(to be built),we can find that the time range of paleo-valley is dated in the LGM at a depth of-60 m to-90 m near Nanjing.It is also indicated that the deep incised-valley channel was narrow and the river flowed swiftly.The ancient Yangtze River deep channel presented partially and deeply incised features near the No.1 Bridge.According to previous publications,much research has been done on the main paleo-channel of the Yangtze River,but few results have been achieved on discharge estimation.In this paper,the incipient velocity and average velocity of the LGM was calculated with Vc = 4.60 d 1/3 h1/6,95 Vc 1.28lg 13.15.h.gd,d = 6 * 90 V 6.5u h≈ d,etc.,in terms of the river shape,sedimentary grain size and sequences near the No.3 and No.1 bridges.Moreover,the discharge in Nanjing reach of the Yangtze River during the LGM has been estimated to be around 12,000-16,000 m3/s according to the relationship of discharge,velocity of flow and cross-section.  相似文献   

18.
近40a来长江流域≥10℃积温的时空变化特征   总被引:3,自引:0,他引:3  
时光训  丁明军 《热带地理》2016,36(4):682-691
基于1970―2013 年长江流域131 个气象站点的日平均气温数据,采用气候倾向率、累积距平、M-K 检验及滑动T 检验等方法分析了该区≥10℃积温的时空变化特征。结果表明:1)突变时间较早的区域主要有嘉陵江流域,中游干流区,太湖流域和下游干流区(1997 年);而岷江、沱江流域,鄱阳湖流域和洞庭湖流域较晚(2001年);长江源头的金沙江流域最晚(2002 年)。2)在区域尺度上,1970 年以来,北亚热带、中亚热带和高原气候区日平均气温≥10℃积温的初日分别以-1.25、-1.39、-0.8 d/10 a 提前,终日分别以1.52、1.43、1.47 d/10 a 推后,持续日数以2.97、2.92、4.62 d/10 a 幅度延长。积温总体上分别以113.5、88.8、77.3℃/10 a 增加。3)≥10℃积温的年际变化存在明显的空间差异,积温增加幅度较大的地区主要集中在汉中―奉节―五峰―吉首―武冈―道县以东的长江中下游地区以及四川盆地、云贵高原、青海高原的个别站点。  相似文献   

19.
末次盛冰期长江南京段河槽特征及古流量   总被引:3,自引:0,他引:3  
根据南京长江大桥、三桥、四桥的地质钻孔资料,绘制南京段长江古河槽地质剖面示意图.对拟建南京长江四桥附近的四个钻孔进行了采样分析,从钻孔沉积物样品的14C年代及阶地形成时间,可以判断,南京段约-60m~-90m的深槽为末次盛冰期时的长江河槽.钻孔揭示,南京段长江古河槽狭窄陡峭,呈V型,在南京长江大桥附近形成局部深切.根据长江三桥、长江大桥附近古深槽断面形态及底部沉积物颗粒级配,选用沙莫夫公式、河海大学公式等,计算了末次盛冰期时河槽底部的泥沙起动流速及断面平均流速.根据流量-流速-过水断面之间的关系式,计算得出末次盛冰期时长江的流量约为12000~16000m3/s.  相似文献   

20.
巢湖凌家滩遗址古人类活动的地理环境特征   总被引:3,自引:0,他引:3  
通过对巢湖凌家滩文化遗址的野外勘查、采样和室内磁化率、烧失量、化学元素及光释光年代分析,结合巢湖湖泊岩芯记录的中全新世环境特征、研究区较高分辨率遥感影像和文物考古成果,综合研究表明:古凌家滩人生活于中全新世气候适宜期,其文化的发展和繁荣处在气候由温暖湿润向温和略干转换的过渡阶段;晚更新世末期堆积形成的地面(OSL年代11.6 ±1.0 ka B.P.)是古凌家滩人生活的地貌面,本区古地貌面海拔以及拔河高度与现今不同,这与该区新构造运动沉降和气候-水文因素作用有关;中全新世温暖湿润的气候条件下,太湖山南麓台地被进一步切割为山前长条形岗地与河流相间的地貌形态,遗址所在的长岗岗地是东、西、南三面临水的"半岛"环境,河川相连,便于水运交通、渔猎和水稻种植。  相似文献   

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