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。     

乌鲁木齐城市灾害特征及对环境的影响

乌鲁木齐市地处欧亚大陆腹地 ,三面环山 ,地形复杂 ,气候多变 ,生态环境脆弱 ,是多种灾害频繁发生的主要地区之一。乌鲁木齐每年都有程度不同的灾害发生 ,特别是人为灾害———环境污染。近年来 ,随着城市人口密集和社会发展 ,生命线工程、城市基础设施建设使人为灾害发生的频次越来越高 ,城市灾害所带来的损失和破坏性也在大幅增加。因此 ,研究如何防御和减轻自然灾害和人为灾害对城市和环境的破坏 ,已成为一个重大的社会问题。     

论湖南生态环境恶化加剧了洪旱灾害

总结了湖南近年洪旱灾害特征，除了气象因素以外，论证了灾害加剧频发的原因是人口激增与资源不合理开发导致了生态环境恶化：森林锐减，水土流失，环境污染，洞庭湖生态环境变化的影响及水利失修等，据此，提了防灾减灾对策建议。     

青海省河湟地区气象灾害变化特征分析

通过对青海省河湟地区1961～2017年气象灾害的时空变化特征分析发现:河湟地区年平均低温冷害次数随时间变化呈微弱减少趋势;生育前期干旱在河湟地区农牧业生产中较为突出;干旱日数呈显著下降趋势,循化干旱日数最多,海晏干旱日数最少;雪灾发生次数呈明显下降趋势,1989年雪灾发生次数最多,湟中县为发生雪灾次数最多的地区;年暴雨日数波动较大,1961年暴雨日数最多,为55d; 20世纪90年代之前年冰雹日数较多,至90年代之后年冰雹日数急剧下降,呈减少趋势。     

天气保险正流行

<正>近年来,由于全球气候变暖,极端气候事件增多,各种气象灾害日趋严重。这不仅影响了人们的正常生活,还给农业、旅游业、娱乐业等对天气敏感的行业带来了不小的经济损失。为了减少气象灾害带来的损失,一种新的保险种类——天气保险便应运而生。所谓天气保险,是指因天气导致企业或个人遭受经济损失后,由保险公司向投保者提供赔偿的一种保险方式。天气保险可以用于娱乐业、旅游业、建筑业、零售业、农业、饮食业、运输业等方面。     

四川省水电投资经营集团有限公司

2008年初，历史罕见的强烈低温雨雪灾害席卷川南等地，给当地电力设施造成巨大破坏。灾害面前，省水电集团反应迅速、组织有力、措施得当，所属企业干部职工以英勇牺牲的彭显松同志为榜样，领导身先垂范，上下众志成城，最大程度地确保了灾区群众欢度春节的用电需求，受到各级领导和社会高度赞扬。     

东部农业区春季干旱变化特征分析及成因初探

利用50多年青海省东部农业区的12站气象资料及青藏高原季风指数研究表明:春季干旱指数SPI变化倾向率为-0.33/10a,呈略减少趋势,减少的趋势不显著;春季东部农业区区域性轻旱、中旱、重旱、特旱分别出现12、5、4、0次,共出现21次,未出现特旱。出现干旱(包括轻旱、中旱和重旱)的几率为38.9%;春季出现过4次明显的区域性大旱,平均每13.5年发生1次,21世纪初以来我省东部农业区出现大旱的几率明显减少;近50年,春季高原季风指数以2.68gmp/a速率增加,增加趋势显著;东部农业区的干旱指数SPI与同期、前期高原季风指数的相关分析表明,高原夏季风越强,东部农业区的降水就越多,干旱指数越小,不易出现旱情;春季干旱指数SPI与同期5月北大西洋—欧洲区极涡强度指数、冬季赤道中东太平洋200hPa纬向风指数成反比,5月北大西洋—欧洲区极涡强度指数、冬季赤道中东太平洋200hPa纬向风指数越强,春季干旱指数SPI越小,春季降水量则偏少,容易发生干旱;与5月多变量ENSO指数、5月北太平洋遥相关指数、春季印度洋暖池面积成正比,这些指数较强,则春季高原指数越大,春季降水量较多,不容易发生干旱。     

秦皇岛市气候变化对河流径流的影响及对策

50年来秦皇岛市气候明显变暖，多年平均气温上升约2℃；同时变干，降水减少18．3％，进而使河流径流也明显减少，其幅度超过30％。河流径流减少给生态系统带来广泛复杂的影响，也给农业、工业、城乡建设带来威胁，因此必须尽快采取发展节水技术、污水治理循环利用、海水淡化等措施。     

中国动态

大气系统发生紊乱 从年初冰雪灾害，到西南5省大早和近期南部地区特大暴雨以及北方地区罕见高温，中国经历了各种极端天气的考验。这些极端天气，不仅出现在中国，全球范围内今年也是北半球集体高温，     

红水河流域1961—2011年极端气温变化特征分析

以红水河流域1961—2011年9个气象站点的月平均气温、月平均最高气温、月平均最低气温为基础,运用气候倾向率、小波分析、Mann-Kendall突变检测法和反距离插值法对流域50年的极端气温变化进行时空定量分析。结果表明:1流域平均温度、极端高温和极端低温的气候倾向率呈上升趋势,平均气温和极端低温的气候倾向率均低于全国水平,而极端高温的气候倾向率高于全国水平。2流域极端高温的突变年为2002年和2009年,极端低温的突变年为1985年,平均温度突变年为1996年。3流域50年来极端高温存在着28年左右的震荡周期,极端低温在14—17年较大的时间尺度上经历了低—高—低—高的变化过程,中小尺度上6—8年的周期变化明显,而流域的平均温度存在27年左右的震荡周期。4流域极端高温变幅较大,总体上呈西北高、东南低的空间分布格局,极端低温呈"冷—热—冷—热"的空间分布格局,平均气温总体上呈典型的经向分布特征。     

The Management of a Large Mediterranean Reservoir: Storage Regimens of the Yesa Reservoir,Upper Aragon River Basin,Central Spanish Pyrenees

Agriculture in Mediterranean countries is mainly based upon the irrigation of productive areas in the lowlands. For this reason, it is necessary to store large volumes of water in reservoirs located in mountain headwaters. These reservoirs have a relatively simple regimen of storage, increasing the water stored during the wet season (from October until May) and reaching the maximum volume shortly before the beginning of the hot, very dry season, when the water is released. This paper considers the storage regimen (inflow and outflow) of the Yesa Reservoir in the Spanish Pyrenees as an example of management of a large reservoir in a mountain Mediterranean environment, subject to a strong interannual variability. On average, the highest water storage level is achieved by retaining the high flows of the Aragón River in autumn and spring. Nevertheless, the irregularity of rainfalls and the existence of changes in the hydrological regimen lead to changes in the patterns of reservoir filling. Two patterns were identified in the Yesa Reservoir: (1) a quick increase of the stored volume in autumn, a stabilization in winter, and a new increase in spring; and (2) a continuous increase from October until May. These patterns are distributed in time over different periods since the construction of the reservoir in 1959, demonstrating the adjustment of the reservoir management to changes in the hydrological regimen.     

秋作的资源利用及效益分析

本文针对四川攀西地区冬干春旱的气候特点,分析了9种晚秋作物的产量、经济效益、生长发育动态及资源利用状况。结果表明,在8月底播种或移栽条件下,秋大麦、秋洋芋、秋豌豆、秋荞麦及秋菜的产量或效益较高。不同秋作可供不同地点或不同种植制度下选择。文章还对主要秋作的关键栽培技术进行了讨论。     

2015-2018年衡阳市城区环境空气污染特征分析

本文利用2015~2018年衡阳市城区空气质量监测数据,分析环境空气污染特征及变化趋势。研究结果表明:2015~2018年衡阳市城区环境空气以PM2.5、PM10、O3污染为主,其中PM2.5和PM10年均值浓度呈下降趋势,O3年均值浓度呈不规则波动变化;年内时空变化上,O3呈现夏、秋季浓度高和冬、春季浓度低的特点,PM2.5和PM10呈现出夏季浓度低、冬季浓度高的特点。针对衡阳市空气污染物特征,提出了衡阳市城区空气质量改善的对策建议。     

宁夏近51年气候变化特征分析

利用宁夏10个气象站1960-2010年日气温和降水资料,对宁夏气温和降水的时空变化特征进行了分析.结果显示:①宁夏整体呈现暖干化趋势,但存在区域间差异.②近51年来宁夏年平均气温呈上升趋势,冬季升温幅度大,秋季升温幅度最小.③年平均降水量总体呈现减小趋势,春季微弱增加,冬季降水量显著增加,夏季降水微弱减少,秋季降水减少明显.④通过Kriging空间差值法分析表明,年平均气温总体呈现由西南向西北递增的趋势,中、北部增温较明显；平均年总降水量总体呈现由西南向西北递减的规律,中、北部降水量减小最为明显.     

大气降尘中多环芳烃的分布特征及源解析

为探讨大气降尘中多环芳烃的污染水平和来源的解析,于2008年冬、春、夏、秋四个季节采集了北京昌平地区大气降尘样品,采用超声抽提方法,使用GC/MS测定了样品中PAHs的含量。结果表明,冬、春、夏、秋四个季节样品中多环芳烃总量分别为18.6μg/g、17.3μg/g、15.1μg/g和11.0μg/g,单体化合物均值分别为1.04μg/g、0.96μg/g、0.84μg/g和0.61μg/g。与其他城市监测结果比较可知:昌平地区大气降尘中PAHs含量相对较低。使用多种方法对降尘中的PAHs来源进行解析,结果表明:化石燃料燃烧在不同季节中的贡献相对稳定,燃煤在冬季为多环芳烃主要来源之一,在其他季节贡献相对较低。     

Cost-effectiveness of tillage methods to reduce phosphorus loss from agricultural land

In this paper, we estimate the cost-effectiveness of tillage methods as a measure to reduce phosphorus loss. The study was based on real-world information on costs. Data on phosphorus loss for different soil tillage methods were modelled. The cost-effectiveness of various soil tillage methods were related to autumn ploughing. The results showed large variation in cost-effectiveness related to erosion risk. Furthermore, spring harrowing was the most cost-effective method to reduce phosphorus loss, followed by autumn harrowing and spring ploughing in spring cereals. Implementation of changed tillage methods showed lower costs for spring cereals compared to winter wheat. The differences in costs between areas were most evident for spring tillage due to differences in yields and agronomic management. Cost-effectiveness is an important criterion in selecting mitigation methods, but due to large variations in the effect of changed tillage, these should be locally adapted to the high risk areas of erosion.     

四川省城市环境空气质量及变化趋势

本文根据2000～2009年四川省24个地级城市例行空气监测数据,按照《环境空气质量标准》(GB3095-1996)中的二级标准,采用综合污染指数法分析了四川省近10年环境空气质量的现状、变化趋势及影响因素。结果表明:从年际变化看,可吸入颗粒物浓度呈下降趋势,二氧化硫、二氧化氮浓度变化较平稳;年内变化显示,各污染物浓度季节变化明显,冬季污染最严重,污染程度由高到低的顺序为冬季、春季、秋季、夏季。全省综合污染指数呈下降趋势,空气污染程度得到了明显缓解,空气质量逐渐变好。     

Streamflow Responses to Climate Change: Analysis of Hydrologic Indicators in a New York City Water Supply Watershed

Recent works have indicated that climate change in the northeastern United States is already being observed in the form of shorter winters, higher annual average air temperature, and more frequent extreme heat and precipitation events. These changes could have profound effects on aquatic ecosystems, and the implications of such changes are less understood. The objective of this study was to examine how future changes in precipitation and temperature translate into changes in streamflow using a physically based semidistributed model, and subsequently how changes in streamflow could potentially impact stream ecology. Streamflow parameters were examined in a New York City water supply watershed for changes from model‐simulated baseline conditions to future climate scenarios (2081‐2100) for ecologically relevant factors of streamflow using the Indicators of Hydrologic Alterations tool. Results indicate that earlier snowmelt and reduced snowpack advance the timing and increase the magnitude of discharge in the winter and early spring (November‐March) and greatly decrease monthly streamflow later in the spring in April. Both the rise and fall rates of the hydrograph will increase resulting in increased flashiness and flow reversals primarily due to increased pulses during winter seasons. These shifts in timing of peak flows, changes in seasonal flow regimes, and changes in the magnitudes of low flow can all influence aquatic organisms and have the potential to impact stream ecology.     

乐山市臭氧生成与前体物之间的关系及其敏感性和控制分析

为初步了解乐山市臭氧生成的主要特征和科学管控,采用Pearson相关性分析法分析一年来臭氧及其前体物之间的相关性,并采用OBM模式和VOCS/NOX比值法分别讨论臭氧生成的敏感性和控制性特征.结果 表明:乐山市氮氧化物与臭氧在夏秋两季呈现正相关,在春冬两季呈负相关;从臭氧的敏感性分析得出臭氧生成潜势PO3-NO:夏季＞...     

Direct and indirect hydrological controls on E. coli concentration and loading in midwestern streams

This study investigates hydrological controls on E. coli concentration and loading in two artificially drained agricultural watersheds (58 and 23 km(2)) of the U.S. Midwest. Stream E. coli concentrations are significantly (p < 0.02) lower at base flow than high flow; however, E. coli load is significantly higher at high flow than at low flow (p < 0.001). Although E. coli concentrations are not significantly higher (p = 0.253) in summer/fall (3269 MPN/100 mL) than in the winter/spring (2411 MPN/100 mL), E. coli load is significantly higher (p < 0.05) in winter/spring (346 MPN/day) than in summer/fall season (75 MPN/day). Correlation analysis indicates that discharge and precipitation are the best indicators of E. coli concentration and 7-d antecedent precipitation (7dP), the best indicator of E. coli loading in the watersheds studied regardless of flow conditions and location. However, E. coli concentration and loading best correlate to 7dP and turbidity at base flow. A spatial dependency is also observed at base flow with E. coli concentration and load correlating better to 7dP in the headwaters and to turbidity in the lower reaches of the watersheds studied. For high flow conditions, E. coli concentration and loading are poorly correlated to most variables, except stream water temperature and 7-d antecedent discharge. These results are consistent with those reported in the literature and suggest that, at least during base flow conditions, turbidity and 7dP may be usable in artificially drained landscapes of the Midwest to identify potential hot spots of E. coli contamination.