Response of snow hydrological processes to a changing climate during 1961 to 2016 in the headwater of Irtysh River Basin, Chinese Altai Mountains

With changing climatic conditions and snow cover regime, regional hydrological cycle for a snowy basin will change and further available surface water resources will be redistributed. Assessing snow meltwater effect on runoff is the key to water safety, under climate warming and fast social-economic developing status. In this study, stable isotopic technology was utilized to analyze the snow meltwater effect on regional hydrological processes, and to declare the response of snow hydrology to climate change and snow cover regime, together with longterm meteorological and hydrological observations, in the headwater of Irtysh River, Chinese Altai Mountains during 1961-2015. The average δ^(18) O values of rainfall, snowfall, meltwater, groundwater and river water for 2014–2015 hydrological year were-10.9‰,-22.3‰,-21.7‰,-15.7‰ and-16.0‰, respectively.The results from stable isotopes, snow melting observation and remote sensing indicated that the meltwater effect on hydrological processes in Kayiertesi River Basin mainly occurred during snowmelt supplying period from April to June. The contribution of meltwater to runoff reached 58.1% during this period, but rainfall, meltwater and groundwater supplied 49.1%, 36.9% and 14.0% of water resource to annual runoff, respectively. With rising air temperature and increasing snowfall in cold season, the snow water equivalent(SWE) had an increasing trend but the snow cover duration declined by about one month including 13-day delay of the first day and 17-day advancement of the end day during 1961–2016. Increase in SWE provided more available water resource. However, variations in snow cover timing had resulted in redistribution of surface water resource, represented by an increase of discharge percentage in April and May, and a decline in Juneand July. This trend of snow hydrology will render a deficit of water resource in June and July when the water resource demand is high for agricultural irrigation and industrial manufacture.

Valuating service loss of snow cover in Irtysh River Basin

Snow cover provides essential resources and services for human well-being and socioeconomic development in arid areas. With the change in snow cover resulting from climate change that causes concerns about its consequences, there is a pressing need to analyze and understand its impact on the benefits that people has been enjoying from snow cover. These can be derived from the variation in economic value of snow services, that are demanded to meet socioeconomic activities. Based on the average decline mass of snow cover from 1979 to 2016 in Irtysh River Basin, we use the approach by applying economic evaluation to estimate the annual value loss of snow services. Considering the decreasing trend of snow cover mass at rates of 10.2 Mt per year (p < 0.05) or 0.3% per year, the annual service loss in Irtysh River Basin is currently worth up to CN 196 million. Within it, the service loss of climate regulation contributes the most, or about CN 84.7 million. The loss of freshwater service contributes only about 19%, implying that there would be a significant underestimation of service loss if only water supply would be considered. This may cause biased decision-making when we are facing the challenges of declining services as a result of climate change, impacting on the balancing of socioeconomic development and environment conservation for the sustainability over a long term.

Effects of reservoirs on seasonal discharge of Irtysh River measured by Lepage test

The Irtysh River is an intemational river partially joining the territories of China, Kazakhstan, and Russia. Cascade reservoirs have been constructed in the upper reaches of the river and their effects on the seasonal discharge of the middle and lower reaches were analyzed considering the mean and dispersion of the seasonal discharge. The Lepage test, which is a nonparametric, two-sample test for detecting location and dispersion, was used to measure the significance of difference between the pre-dam and post-dam seasonal discharge. The results show that the reservoirs＇ effects on the seasonal discharge varied with the season. In the middle reaches of the river, the summer and autumn discharge decreased significantly and their inter-annual variabilities also decreased significantly. The summer and autumn precipitation over the Irtysh River Basin changed little before and after the operation of the reservoir, which indicates that the discharge changes mainly due to water storage of the reservoirs. The reservoirs store water in summer and autumn and store more water in a wet year, which leads to the reduction of the mean and dispersion of the summer and autumn discharge. The winter discharge increased significantly because the reservoirs released water for power generation. The spring discharge changed slightly. In the lower reaches, only the winter discharge increased significantly, and the other seasonal discharge changed slightly. The reservoirs＇ effects on the seasonal discharge are more significant in the middle reaches than in the lower reaches.

Spatial distribution of Dactylogyrus wunderi Bychowsky on gills of Abramis brama orientalis Berg (Leuciscinae) in Irtysh River, China

The spatial distribution of the monogenean Dactylogyrus wunderi Bychowsky,1931 on the gill filaments of the bream Abramis brama orientalis Berg(Leuciscinae) inhabiting the Irtysh River of Xinjiang,China was investigated from June to July 2012.D.wunderi was identified by sequencing a fragment of its ITS rDNA region.Sixty-five fish were examined,with 55% testing positive for monogenean infection.The prevalence of the parasite in the left and right gill arches was 46% and 48%,respectively.In fish with a large body length,the prevalence of the parasite and the infection intensity did not significantly differ between the right and left gill arches but both were slightly higher in the former.Among the three size groups of fish(small,medium and large) the prevalence and the intensity of infection were lowest in fish with small body lengths.The distribution of the monogenean population in the host gills showed an aggregate distribution,with little change in the degree of aggregation,suggesting that most hosts were either not or only slightly infected by D.wunderi and that the parasite infected only a few hosts.In addition,differences in D.wunderi infections between gill arches of A.brama orientalis were not significant(P>0.05).

Regime dynamics of hydrochemical and toxicological parameters of the Irtysh River in Kazakhstan

Since the Irtysh River flows through the important economic, ecological and social territories of China, Kazakhstan and Russia, the water quality issues growingly draw the attention of the water authorities from these countries. Therefore, a detailed study of the hydrochemical regime and toxicological indicators in Kazakhstan was carried out for understanding the regime dynamics of water quality and its affect factors. The combined assessment of maximum permissible concentration （MPC） of chemical components and biotesting method were proposed and performed for the study area. The results clearly showed that the concentrations of single chemical component at different locations are mostly under MPC standard in a basin scale. However, the watershed surface runoff and tributary stream flow from mining industry areas had high concentration of heavy metals and had significant impact on the water quality near Ust-Kamenogorsk. Furthermore, even the stream water generally meet MPC standard, the results of biotesting method show the toxicity level of water sample is lethal for the test objects of phytoplankton and Daphnia. The survival rates of most water samples are lower than 46.7%. Hereby, this study strongly suggests using combined water assessment methods to evaluate the water quality.

新疆额尔齐斯河高体雅罗鱼个体繁殖力研究

新疆额尔齐斯河流域高体雅罗鱼属于自治区二级保护动物,为对其自然群体进行资源修复,于2020年5月,在新疆额尔齐斯河布尔津河段采集高体雅罗鱼117尾,其中雌性Ⅳ期样本53尾,可进行个体繁殖力相关研究。结果表明:繁殖群体由3+~7+龄个体组成,个体绝对繁殖力为(28390~97184)粒,平均为(46955±14102)粒;体长相对繁殖力为(97~253)粒·cm^(-1),平均为(145±32)粒·cm^(-1);体质量相对繁殖力为(70~131)粒·g^(-1),平均为(85±11)粒·g^(-1);从多元回归分析中可以得出卵巢质量与个体绝对繁殖力和体长相对繁殖力均呈正相关,且卵巢重与个体繁殖力之间的偏相关系数系数高于净体质量、年龄和性腺成熟系数;从最佳拟合方程中可以看出个体绝对繁殖力与卵巢质量的拟合度最高(R^(2)=0.916),关系式为F=1.074 m0^(2)+153.347 m0+19611.041。因此,通过卵巢质量与个体绝对繁殖力的拟合方程可以预测额尔齐斯河流域中高体雅罗鱼自然种群的繁殖能力,从而丰富其繁殖生物学资料,为高体雅罗鱼的资源养护和人工繁育提供科学依据。

新疆北部六种草地类型土壤碳氮磷生态化学计量特征

草地土壤碳氮磷含量及其生态化学计量的空间变异关系到草地生态系统的功能与稳定性。海拔、气候、土壤性质和植被如何影响新疆北部典型牧区额尔齐斯河(简称额河)流域土壤碳氮磷化学计量的空间格局尚不清楚。本文选取了额河流域六种主要草地类型的65个样点(0~10 cm、10~20 cm土层)进行研究。结果表明:(1)高寒草甸、山地草甸、温性草甸草原有机碳(39.06~62.59 g·kg^(-1))、总氮含量(3.87~6.95 g·kg^(-1))以及六种草地类型的土壤总磷含量(0.53~1.59 g·kg^(-1))总体上高于中国土壤平均值(24.56 g·kg^(-1)、1.88 g·kg^(-1)、0.56 g·kg^(-1)),而六种草地类型的土壤碳氮比(5.03~9.97)、碳磷比(7.50~52.38)以及温性草原、温性荒漠草原和温性荒漠土壤氮磷比(1.53~3.72)低于中国或全球土壤平均值(11.40、64.30、3.90)。(2)土壤碳氮磷含量以及碳磷比、氮磷比随着海拔升高(328~2655 m)、降水量增加以及温度降低而显著增加,并且与植被特征、土壤理化性质有显著的相关性。随着海拔的升高,土壤有机碳、总氮含量与土壤碳磷比在土层间的差异逐渐增加。(3)结构方程模型结果表明,海拔与气候因子对土壤碳氮磷含量及其生态化学计量的影响效应最高,海拔通过改变温度、降水、植被特征、土壤理化性质影响土壤碳氮磷含量,最终影响生态化学计量。未来应进一步开展气候变化对土壤碳氮磷及其生态化学计量影响的跨区域尺度研究。

额尔齐斯河库威站日尺度的降雨融雪径流模拟

额尔齐斯河流域受地理条件的影响,流域内水文气象站点较少,基础资料匮乏,而融雪洪水在该流域的汛期及水资源管理上有着较大影响。本研究通过应用降水和气温的再分析产品及AVHRR积雪数据,利用K-means聚类法进行不同径流时期特点的划分,并在不同时期构建相应SRM+LSTM模型,并使用2009年数据及2023年实地观测的径流数据进行验证。结果表明:再分析产品CMFD能够较好地应用于额尔齐斯河流域,并能根据降水、温度、积雪及径流间的关系得到不同径流划分时期,即12月11日—次年4月10日为积雪退水期、4月11日—8月10日为融雪降水产流期、8月11日为降水产流期。SRM模型模拟效果较差,大部分径流纳什效率系数(NSE)<0;而SRM+LSTM模型能够较好地模拟该流域的不同时期的径流,决定系数R2均能达到0.5以上,纳什效率系数也能达到0.5以上,证明SRM+LSTM模型能够较好地应用于该地区,精度较高。

新疆3种维管植物新记录

报道了1个中国维管植物新记录种—波叶菊(Chrysanthemum sinuatum Ledeb.),2个新疆维管植物新记录种—刺果茶藨子(Ribes burejense Fr. Schmidt.)、赛北紫堇[Corydalis impatiens (Pall.) Fisch.]。根据标本和野外观察对3个新记录种进行了形态描述,并提供了部分形态特征和生境照片。该报道丰富了新疆地区维管植物多样性,为该地区的植物保护以及物种编目提供了基础数据。

“陆冰丝绸之路”建设研究——以额尔齐斯河-鄂毕河运输通道建设为例

随着额尔齐斯河—鄂毕河航道重建与“冰上丝绸之路”建设的不断推进,“陆冰丝绸之路”建设迎来重大历史机遇。作为贯穿亚欧大陆和连接“陆冰丝绸之路”沿线多国的国际水运通道,额尔齐斯河—鄂毕河航道在受到相关各国关注的同时,其国际战略价值愈发显现。在剖析“陆冰丝绸之路”建设的重要性以及分析额尔齐斯河—鄂毕河流域各国合作基础及其对“陆冰丝绸之路”的重要作用的基础上,结合额尔齐斯河—鄂毕河的水文特征、航运条件,以及航运重建面临的挑战,提出额尔齐斯河—鄂毕河支撑“陆冰丝绸之路”建设的可行路径。结果显示:额尔齐斯河—鄂毕河具有优越的航运区位、良好的航运条件及一定的运输承载力,在经济、政治方面均能够对“陆冰丝绸之路”建设起到重点支撑作用;额尔齐斯河—鄂毕河作为连接“陆冰丝绸之路”沿线国家的陆海交通网络的重点河流,利益相关方亟需重建两河航道,强化河流沿线国家协作,形成以可持续发展为原则、以“社会、经济、生态三效应协同”为理念的联合开发机构。

额尔齐斯河发现中国新纪录种——格鲁西东欧螯虾

2021年5月,在额尔齐斯河下游哈巴河县河段的渔获物中发现螯虾7尾,成年个体长11.4~17.5 cm,体质量81.7~127.6 g。经查询国内外分类学文献,依据其形态特征、栖息生境特点等鉴定为格鲁西东欧螯虾,拉丁学名:Astacus leptodactylus Eschscholtz 1823,俗名:窄爪螯虾(narrow-clawed crayfish)、多瑙河螯虾(Danube crayfish)等。格鲁西东欧螯虾为中国新纪录种,填补了我国中西部地区螯虾科的空白,可作为北方地区(寒冷水域)水产养殖的后备种质资源。

北极茴鱼胚胎及仔鱼发育

研究对人工繁殖的北极茴鱼(Thymallus arcticus grubei)胚胎发育开展系统观察,记录分析其胚胎及仔鱼发育各时期的形态特征,旨在为北极茴鱼的人工繁育和种质资源保护提供必要的基础数据。结果显示,北极茴鱼受精卵呈圆球形,金黄色,沉性卵,未吸水卵径(2.46±0.14)mm,吸水卵径(3.14±0.18)mm,卵黄质内有多个油球。油球的数量和空间分布在胚胎发育过程中发生了规律性变化。在孵化水温(11.06±0.72)℃,溶氧8.3—9.8 mg/L条件下,历时301h完成整个胚胎发育过程,所需积温为3384.84h·℃,经历合子期、卵裂期、囊胚期、原肠胚期、神经胚期、器官形成期和孵化出膜7个阶段,共26个时期。北极茴鱼仔鱼尾鳍、胸鳍的分化和眼色素沉积在受精卵胚胎发育后期就已经完成,背鳍、腹鳍、臀鳍和脂鳍等在胚后发育过程中相继分化。其初孵仔鱼平均全长为(9.33±0.35)mm,仔鱼卵黄囊呈圆球形,18日龄时卵黄囊和油球被完全消耗。其早期发育阶段(0—16日龄)的生长特性符合公式:y=0.0005x^(4)–0.0201x^(3)+0.2264x^(2)–0.3773x+9.6102(R^(2)=0.9968)。研究初步阐明了北极茴鱼的胚胎发育和仔鱼发育的时序特征,为今后的苗种规模化繁育提供了理论基础。

额尔齐斯河尖鳍鮈寄生舌状绦虫裂头蚴的种群动态及空间分布研究

为了研究额尔齐斯河流域尖鳍鮈(Gobio acutipimnatus)腹腔寄生绦虫(tapeworm)的感染情况及分布类型,2020年10月,对额尔齐斯河鱼类寄生虫病原调查过程中发现尖鳍鮈腹腔寄生有绦虫蚴,经形态学和分子生物学鉴定确定为舌状绦虫裂头蚴(Ligula intestinalis plerocercoid)。运用统计学方法对尖鳍鮈腹腔寄生的舌状绦虫裂头蚴的总体、不同体长组的感染情况进行统计,进一步分析其空间分布特点。结果显示,在检查的346尾尖鳍鮈中,共检出320只舌状绦虫裂头蚴,总感染率、平均感染丰度和平均感染强度分别为52.30%、0.92±0.06和1.77±0.08;在6<L≤8体长组感染率和平均感染丰度最高,在L>10体长组感染率和感染丰度最低,尖鳍鮈各体长组的感染率和平均感染丰度呈先上升后下降的趋势;6<L≤8体长组与其他体长组之间均呈显著性差异(P<0.05);舌状绦虫裂头蚴在宿主中的分布类型为聚集分布,且在L>10体长组聚集强度最强(0<K<1)。

人类活动对额尔齐斯河流域碳储量的影响

基于阿尔泰山额尔齐斯河流域2000—2020年土地利用数据,运用InVEST模型,模拟并分析了不同时期该流域碳储量空间分布,并探讨了人类活动对碳储量空间分布的影响。研究表明:(1)流域内土地利用类型以草地和未利用地为主,2000—2020年土地利用格局发生明显改变,耕地和城乡、工矿、居民用地分别增加2619.35 km^(2)和186.68 km^(2);草地和水域分别增加4725.13 km^(2)和33.47 km^(2);林地和未利用地分别减少2328.88 km^(2)和5237.76 km^(2)。(2)研究期间,流域内碳储量空间分布格局较为相似且呈现带状分布,高值区分布在高海拔地区,低值区分布在低海拔地区,2000年、2005年、2010年、2015年和2020年流域内碳储量总量分别为641.60 Tg、645.78 Tg、646.83 Tg、650.28 Tg和665.91 Tg,其年增长率为0.95%,呈现上升趋势。(3)流域内碳储量减少或增加的区域呈现点状分布,2000—2020年碳储量的增加量大于减少量,因此,额尔齐斯河流域的固碳能力呈上升趋势。

基于模型试验的小型水库溢洪道消能结构对水力特征影响研究

为研究额尔齐斯河流域小型水库溢洪道工程消能井结构设计,采用水工模型试验方法 ,对竖井式溢洪道不同设计方案开展模型试验结果分析,从井内上、下游水力运营特征参数评价工程设计合理性。试验表明,消能井内流速水平随底板直径为递减,方案中直径每增大10 cm,井内平均流速可减少12.1%;从出流段流速表现得知,底板直径直径60 cm方案下存在局部波幅,且愈大的底板直径方案,对出流段流速水平限制减弱。时均压强监测计算表明,控制底板直径参数,可限制时均压强递增节点断面,同时抑制时均压强水平,但仍然在直径60 cm方案下存在压强不稳定变化段。对比研究认为该水库溢洪道消能井底板直径为50 cm最为适配。结果可为竖井式溢洪道消能井设计及模型试验研究分析提供参考。

额尔齐斯河流域气候特征及变化趋势分析

选取额尔齐斯河流域斋桑泊、塞米巴拉金斯克、鄂木斯克、托博尔斯克4个代表站1948-1995年实测逐月降水与气温资料,利用距平分析法、5年滑动平均法、坎德尔秩次相关检验法及相关水文统计方法对流域内气候特征及变化趋势进行了分析.结果表明：额尔齐斯河流域年均降水量在200-500mm之间,主要集中于夏、秋两季,下游降水较上游丰富,但年际变化下游小于上游;年及四季降水量在1948-1995年期间整体呈上升趋势;流域年均气温自上游到下游逐渐降低,但年际变化逐渐增大,流域年均气温多年来总体呈上升趋势.

额尔齐斯河-斋桑湖流域近20年来土地利用/土地覆被时空演变

土地利用/土地覆被变化(LUCC)是影响生态环境和气候变化的主要驱动力之一,同时又是受其影响的结果。LUCC研究对于开展生态环境变化及气候变化的研究均具有重要的意义。针对目前境外LUCC研究中土地利用/覆被分类效率低的问题,探索一种适用于大数据量而又精度较高的分类方法。以额尔齐斯河国外部分-斋桑湖流域为研究区域,以1990年及2007年的Landsat TM/ETM+夏秋季影像以及DEM作为数据源,综合利用影像光谱、纹理信息参与到决策树构造中,进而利用决策树分类方法分别提取这两个时期的土地利用/覆被空间分布信息,最后分析两个时期的土地利用时空变化状况。实验结果表明:(1)光谱与空间纹理信息参与的决策树分类方法具有较高的分类精度;(2)两个时期的土地利用变化分析发现,近20年来该区域土地利用发生了较大的变化,耕地和灌木林地大面积减少,而低覆盖度草地和未利用地却显著增加。

基于大型底栖动物完整性指数的新疆额尔齐斯河健康评价

为建立我国西北地区跨境河流生态系统健康的评价指标与标准,应用B-IBI(benthic-index of biotic integrity,底栖动物完整性指数)评价新疆额尔齐斯河流域的健康状况.于2012年7月、8月、10月及2013年5月在额尔齐斯河全流域设10个典型采样点,进行4次大型底栖动物调查,从23个候选生物指标中筛选出适用于构建额尔齐斯河B-IBI评价体系的参数,主要包括总分类单元数、EPT(蜉蝣目、襀翅目、毛翅目)分类单元数、前3位优势分类单元个体相对丰度、襀翅目个体相对丰度和黏附者个体相对丰度.以参照点B-IBI的25%分位数作为健康评价标准来确定B-IBI的评价等级:B-IBI>2.04为极好,1.53<B-IBI≤2.04为好,1.02<B-IBI≤1.53为一般,0.51<B-IBI≤1.02为差,B-IBI≤0.51为极差.结果表明:在所有采样点中,6个采样点处于健康状况极好或好的状态,3个采样点健康状况一般,1个采样点健康状况较差;各采样点B-IBI在不同月份变化各异.整体来看,额尔齐斯河的水体健康状况较好,但局部河段水体受到不同程度污染.基于B-IBI的健康评价结果与其他生物指数〔Chandler计分制生物指数、BMWP(biological monitoring working party)分数系统分值〕评价结果相一致,表明所构建的B-IBI评价指标与标准对额尔齐斯河的健康状况评估具有较好的适用性,可作为额尔齐斯河流域水体环境监测的一种有效手段.

基于能量平衡对额尔齐斯河流域融雪过程的研究

为定量描述额尔齐斯河流域积雪的消融过程,建立了利用基于能量平衡的积雪模型,对流域内库威积雪站2014年1月4日-3月28日积雪的积累和消融过程进行了模拟.结果表明:模型能够很好的模拟出融雪期净辐射能量的变化过程,对雪水当量的模拟结果也非常好,雪水当量的观测值和模拟值之间的Nash系数达到了0.989.在积雪的积累期,雪表的净辐射、感热、潜热通量的绝对值以及地表热通量明显低于积雪的消融期.在积累期,感热和潜热通量以及土壤热通量受到雪层厚度的影响.当雪水当量小于10 mm时,感热和潜热通量的绝对值偏高,土壤热通量的波动性也偏大.在积累期积雪的物质损失全部为升华损失,升华量为2.74 mm;在消融期,积雪的融化量为66.26 mm,升华量为2.04 mm.净辐射对积雪物质损失的贡献达到了83.1%,湍流通量对积雪物质损失的贡献达到16.9%.由于在融化期土壤热通量为正值,因此土壤热通量对融雪没有贡献.

新疆额尔齐斯河周丛藻类群落结构特征研究

周丛藻类是新疆跨境河流土著及特有鱼类重要的基础饵料资源,然而在该地区有关周丛藻类的研究目前尚属空白。有鉴于此,2012年7、8、10月对新疆跨境河流——额尔齐斯河全流域的周丛藻类群落结构进行了系统的调查分析。结果表明,周丛藻类隶属7门70属178种,由硅藻门、绿藻门、蓝藻门、裸藻门、黄藻门、金藻门和甲藻门组成,其中硅藻门有92种并占据绝对优势(51.7%),绿藻门49种(30.3%),蓝藻门20种(11.8%),裸藻门5种(2.8%),黄藻门3种(1.7%),金藻门2种(0.1%),甲藻门仅1种(0.6%),周丛藻类在不同月份的种类数存在显著差异(P<0.01)。优势种主要为硅藻门的嗜盐舟形藻(Navicula halophila)、钝脆杆藻(Fragilaria capucina Desm)、极小桥弯藻(Cymbella perpusilla Cl)以及蓝藻门的皮状席藻(Phormidium corium Gom)等。研究期间,额尔齐斯河周丛藻类的密度和生物量的均值分别为1105.5×106 ind./m2和2692.0 mg/m2,不同月份间密度和生物量的分布差异不显著,但在空间分布上整体趋势为中下游地区高于上游地区。水温和营养盐成为影响其分布的主要环境因子。Simpson多样性指数、Shannon-Wiener多样性指数、Pielou均匀度指数和Margalef丰富度指数的平均值分别是0.38、3.04、0.66和2.55。运用多样性指数和藻类丰度对额尔齐斯河水质评价为轻度污染。