SRESB2情景下未来30年黄河上游龙羊峡库区秋季入库流量变化趋势分析

文章运用甘、青、川境内黄河上游的降水、气温、蒸发量等气象要素,选取龙羊峡作为代表站,运用该站最近21年的入库流量,建立了基于气象要素的龙羊峡秋季入库流量的水文模型。利用hadlay气候预测与研究中心的区域气候模式系统PRECIS在青海省黄河流域的气候基准时段（1961—1990）和SRESB2情景下2011-2040年间的资料,代入上述模型,给出龙羊峡未来30年的秋季入库量变化趋势,并加以分析。     

柴达木盆地气候变化对生态环境的影响

利用累积距平等方法对柴达木盆地近46年（1961～2006年）气温、降水和径流量资料进行了分析，探讨了盆地气候变化特征及其对生态环境的影响。结果显示：柴达木盆地近46年来气温增幅明显，降水呈略多趋势，径流呈减少趋势，区域内土地荒漠化面积大，植被覆盖率低。气候变暖、大风多、降水少、蒸发强是影响该区生态环境建设和改善的主要自然原因之一。     

秦皇岛湿润生态环境变化

利用线性倾向分析、滑动平均和计算干燥度等方法对秦皇岛市1954-2005年降水、气温、相对湿度、蒸发量、干燥度等变化进行分析研究，结果表明：近50年秦皇岛地区气温逐渐升高，降水减少，气候干燥度普遍增大，生态环境呈干旱化趋势，南部干旱化进程较北部大，90年代后干旱化趋势增大。     

湟水河流域气候变化特征及其影响

文章利用1961-2005湟水河流域9个气象台站气温、降水等地面观测资料，研究了湟水河流域气候变化及其对农业的影响。结果表明：湟水河流域2001—2005年比最冷的60年代四季平均气温分别偏高0．7-2．5℃，冬季增温比较显著；年降水量总体变化趋势是中游地区缓慢增加，而上游和下游地区则缓慢减少，流域内年平均降水量呈减少趋势；四季地表蒸发量均在增加，夏秋季大于其它季节；90年代湟水河流域秋季和春季降水的减少，使得秋季和春季发生中（重）干旱的频次明显增加。     

青海省1998年秋季—1999年春季异常气候分析

１９９８年秋季－１９９９年春季全省气温普遍偏高,降水持续偏少。特别是东部农业区和环湖区气温异常偏高,降水异常偏少,蒸发量急剧增加,连续无降水日数达１３０多天,部分地区达到２００多天,出现了气象记录以来最明显的异常气候,导致了东部农业区春播和环湖地区牧草返青期严重缺水,发生了最严重的三季连旱,也是全省有气象记录以来最为严重的     

52年来三江源区气候变化及其环境效应分析

利用"三江源"地区18个气象台站1961—2012年的气温、降水、蒸发以及相对湿度的气象资料,分析了该地区的气候暖湿变化情况。分析发现:1961—2012年期间,三江源整体向暖转化,平均气温、平均最高气温、平均最低气温均在升高,且平均最低气温上升速率明显快于平均气温和平均最高气温;降水量和降水日数均呈增加趋势,说明三江源地区正逐步变湿。由于暖湿变化而产生了一系列的环境改变。     

果洛地区近51年气温及降水的时空变化

文章利用1961~2011年间的实测地面气温和降水资料,通过计算气候趋势系数和气候倾向率等统计量,分析了果洛地区气候的时空变化特征。     

新疆精河县近56年来气候变化特征分析

利用精河县1953-2008年的气温和降水资料，通过回归分析、趋势分析和5年滑动平均法分析得出56年来该县的气温和降水总体呈上升趋势，气候呈暖湿化趋势，其中冬季增温明显，秋季降水增加较多。     

气候变暖下柴达木盆地风速、大风和沙尘暴日数的变化特征分析

利用柴达木盆地9个气象观测站1961～2018年平均气温、风速、大风日数和沙尘暴日数资料,用线性趋势、m-k检验、相关性分析和变异系数对柴达木盆地平均气温、大风和沙尘暴日数变化特征进行详细分析,结果表明,58年来柴达木盆地平均气温呈上升趋势,且通过了0.01的显著性检验。气温突变年份发生在1987年左右,与累积距平曲线的变化趋势相一致,气温由偏冷期过渡为偏暖期。年、四季平均风速、大风日数和沙尘暴日数均呈下降趋势。各站四季大风日数和沙尘暴日数对年的贡献率有所不同。气温与风速、大风日数和沙尘暴日数均呈负相关性。气候变暖是造成柴达木盆地平均风速、大风日数和沙尘暴日数减小的可能原因。风速以大柴旦为中心向四周增大。风速和大风日数的变异系数与气候倾向率有明显的相关性,沙尘暴日数的变异系数与气候倾向率的相关性不明显。     

55年来门源地区气温变化特征分析

为了研究门源地区气温变化特征趋势,作者利用1961~2015年门源地区气象站逐月平均气温、最高气温和最低气温资料,采用线性倾向估计和Mann-Kendall法等方法,分析了近55年来门源地区气温变化特征。研究结果表明:(1)近55年来门源地区年和四季平均气温、最高气温和最低气温均呈极显著的增加趋势,而年和冬季气温日较差呈极显著的减小趋势。(2)门源地区最高气温和最低气温存在着非对称性变化。(3)年平均气温、最高气温和最低气温均表现为60~80年代较气候平均值偏低,90年代基本持平,进入21世纪00年代变暖突出,属于年代最高值,气温日较差在60~70年代比气候平均值偏高,80年代至21世纪00年代基本持平。(4)门源地区年平均气温、最高气温和最低气温在1993~1994年发生突变,气温日较差没有发生突变。     

Establishing a Context for River Rehabilitation, North Fork Gunnison River, Colorado

Initial river rehabilitation efforts along the North Fork Gunnison River in Colorado focused on the use of in-stream structures and channel stabilization to create a single-thread channel with pools along a braided river. These efforts were based on the assumption that the river’s braided planform results primarily from land use during the past century. In order to establish a context for further rehabilitation, we evaluated the possibility that the river might be braided as a result of processes independent of land use. We estimated volume, grain-size distribution, and lithology of sediment sources along the river corridor and evaluated the planform stability of the river during the past century using historical sources, aerial photographs covering 1939–1997, and comparison of bankfull discharge and gradient in the study area to values published for braided and meandering rivers. Our results indicate that the North Fork Gunnison River has been primarily braided in its lower reaches during the past few hundred years, although the channel planform tends toward a single-thread channel during decades of lower precipitation and discharge. Although land use is not the primary cause of braiding along the North Fork Gunnison River, it has decreased channel stability, and rehabilitation efforts should be designed to reduce these effects. Our results illustrate the importance of planning river rehabilitation measures within a historical context that accounts for both catchment-scale and reach-scale controls on channel processes and planform.     

淮河边,30年

我家住在安徽省阜阳市，地处淮河流域。我在淮河边长大，1984年大学毕业后，又有幸分在环保部门工作，从而亲眼目睹了改革开放30年来淮河水质的变迁，特别是近十几年来河水水质的变化。     

River Styles, a Geomorphic Approach to Catchment Characterization: Implications for River Rehabilitation in Bega Catchment, New South Wales, Australia

Analysis of the character and condition of each river style in Bega catchment, and their downstream patterns, are used to provide a biophysical basis to prioritorize river management strategies. These reach-scale strategies are prioritorized within an integrative catchment framework. Conserving near-intact sections of the catchment is the first priority. Second, those parts of the catchment that have natural recovery potential are targeted. Finally, rehabilitation priorities are considered for highly degraded reaches. At these sites, erosion and sedimentation problems may reflect irreversible changes to river structure.     

Effects of River Restoration on Riparian Biodiversity in Secondary Channels of the Pite River, Sweden

Between 1850 and 1970, rivers throughout Sweden were channelized to facilitate timber floating. Floatway structures were installed to streamline banks and disconnect flow to secondary channels, resulting in simplified channel morphologies and more homogenous flow regimes. In recent years, local authorities have begun to restore channelized rivers. In this study, we examined the effects of restoration on riparian plant communities at previously disconnected secondary channels of the Pite River. We detected no increase in riparian diversity at restored sites relative to unrestored (i.e., disconnected) sites, but we did observe significant differences in species composition of both vascular plant and bryophyte communities. Disconnected sites featured greater zonation, with mesic-hydric floodplain species represented in plots closest to the stream and mesic-xeric upland species represented in plots farthest from the stream. In contrast, restored sites were most strongly represented by upland species at all distances relative to the stream. These patterns likely result from the increased water levels in reconnected channels where, prior to restoration, upland plants had expanded toward the stream. Nonetheless, the restored fluvial regime has not brought about the development of characteristic flood-adapted plant communities, probably due to the short time interval (ca. 5 years) since restoration. Previous studies have demonstrated relatively quick responses to similar restoration in single-channel tributaries, but secondary channels may respond differently due to the more buffered hydrologic regimes typically seen in anabranching systems. These findings illustrate how restoration outcomes can vary according to hydrologic, climatic and ecological factors, reinforcing the need for site-specific restoration strategies.     

Analysis of pollution status of River Illo,Ota, Nigeria

An assessment of the pollution status of River Illo, located within River Owo catchments area in Ota, Ogun State, Nigeria, was carried out. The River’s response to deoxygenation due to BOD loading from an abattoir and its dissolved oxygen (DO) level was predicted using the modified Streeter-Phelps model. The average concentrations of measured parameters at the sampling stations include: 2.24 mg/l of DO, 312.85 mg/l of BOD, 782.86 mg/l of chemical oxygen demand, and 620.76 g/l of total solids. The DO model for River Illo showed a positive correlation between measured and calculated DO, while the dissolved oxygen curve gave a double spoon shape of two major segments with distinct zones of degradation, decomposition, and recovery. The self-purification factor (f) for both segments ranged between 0.8 and 1.1 depicting River Illo as a slow moving or sluggish river. The above results revealed slow reaeration of the water body while full recovery from pollution was difficult. The treatment of River Illo before usage is very essential to ensure public health safety of users from waterborne diseases.     

Chemical and isotopic compositions of the Minjiang River, a headwater tributary of the Yangtze River

We describe the anthropogenic impacts on the major dissolved elements (Cl(-), NO(3)(-)-N, SO(4)(2-), and Na(+)) in the water from the Minjiang River (a headwater tributary of the Yangtze River) and upper Yangtze River in relation to increasing human activity. The major element chemistry and hydrogen, oxygen, and sulfur isotopic compositions were investigated. When the Minjiang River flows through the populated Sichuan Basin, the concentrations of Cl(-), NO(3)(-)-N, SO(4)(2-), and Na(+) gradually increase. The increasing SO(4)(2-) in the highly polluted Minjiang River had high delta(34)S values (+6.3 to approximately +13.6 per thousand), implicating the anthropogenic sources of sulfur from air pollutants, domestic wastewater, industrial effluents, and agricultural fertilizers. The water quality of the upper Yangtze River does not worsen after receiving the Minjiang River because the water from the lightly polluted Jinshajiang River contributes most of the total flux in the Yangtze River. However, these rivers deserve attention and further research because the Yangtze River is the most important river in China in terms of water quality.     

气候变化对江河源区生态环境的影响评价

根据江河源区16个气象观测台站40a的气候资料，通过分析发现年平均气温呈上升趋势，普遍升高0．2℃-0．4℃；而降水增率较小，几乎不变；再加上干旱多风、剧烈蒸发，使得区内植被退化，水源涵养能力降低、河流径流锐减、土地荒漠化加剧、水土流失严重、冰川退缩。     

River channel network design for drought and flood control: A case study of Xiaoqinghe River basin, Jinan City, China

Vulnerability of river channels to urbanization has been lessened by the extensive construction of artificial water control improvements. The challenge, however, is that traditional engineering practices on isolated parts of a river may disturb the hydrologic continuity and interrupt the natural state of ecosystems. Taking the Xiaoqinghe River basin as a whole, we developed a river channel network design to mitigate river risks while sustaining the river in a state as natural as possible. The river channel risk from drought during low-flow periods and flood during high-flow periods as well as the potential for water diversion were articulated in detail. On the basis of the above investigation, a network with “nodes” and “edges” could be designed to relieve drought hazard and flood risk respectively. Subsequently, the shortest path algorithm in the graph theory was applied to optimize the low-flow network by searching for the shortest path. The effectiveness assessment was then performed for the low-flow and high-flow networks, respectively. For the former, the network connectedness was evaluated by calculating the “gamma index of connectivity” and “alpha index of circuitry”; for the latter, the ratio of flood-control capacity to projected flood level was devised and calculated. Results show that the design boosted network connectivity and circuitry during the low-flow periods, indicating a more fluent flow pathway, and reduced the flood risk during the high-flow periods.     

洈河，从甜美的睡梦中醒来

受遐迩闻名的山歌老人宁远俊老师多次相约，我镇作协成员，浩浩荡荡，一路前往美丽迷人而充满传奇色彩的黄林桥村。 一 原生态的黄林桥村，好像没有一条像样的路。但，宁老师的女儿宁颜燕，走在前面，那些更具道路功能的路，无形中就来到了她的脚下。