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91.
Groundwater storage, drainage, and interbasin water exchange are common hydrological processes but often difficult to quantify due to a lack of local observations. We present a study of three volcanic mountainous watersheds located in south‐central Chile (~36.9 ° S) in the Chillán volcanic complex (Chillán, Renegado, and Diguillín river basins). These are neighboring basins that are similar with respect to the metrics normally available for characterization everywhere (e.g., precipitation, temperature, and land cover). In a hydrological sense, similar (proportional) behavior would be expected if these catchments would be characterized with this general information. However, these watersheds show dissimilar behavior when analyzed in detail. The surface water balance does not fit for any of these watersheds individually; however, the water balance of the whole system can be explained by likely interbasin water exchanges. The Renegado river basin has an average annual runoff per unit of area on the order of 60–65% less than those of the Diguillín and Chillán rivers, which is contradictory to the hydrological similarity among the basins. To understand the main processes that control streamflow generation, two analyses were performed: (a) basin metrics (land cover, geologic, topographic, and climatological maps) and hydro‐meteorological data analyses and (b) a water balance model approach. The analyses contribute to a plausible explanation for the hydrogeological processes in the system. The soils, topography, and geology of the Chillán–Renegado–Diguillín system favor the infiltration and groundwater movements from the Renegado river basin, mainly to the neighboring Diguillín basin. The interbasin water exchanges affect hydrological similarity and explain the differences observed in the hydrological processes of these three apparently similar volcanic basins. The results highlight the complexity of hydrological processes in volcanic mountainous systems and suggest that a simple watershed classification approach based on widely available data is insufficient. Simple local analyses such as specific flow analysis with a review of the geology and morphology can contribute to a better understanding of the hydrology of volcanic mountainous areas.  相似文献   
92.
1.Overview The 2021 Nobel Prize for Physics was awarded to three scientists for their contribution to the physical understanding of complex systems(The Nobel Committee for Physics,2021).Two of the laureates,Dr.Syukuro MANABE and Dr.Klaus HASSELMANN,are climate scientists.This is the first time a climate scientist has won a Nobel Prize for physics and is thus a great encouragement to the entire climate science community,especially young scientists.Because the two winners'groundbreaking contributions that led to their award were achieved decades ago,young people may not be very familiar with these works.Therefore,to help young scientists better understand the scientific merit of the fundamental works and to inspire them in their future research careers,on 20 October 2021,the young scientist working group of The China National Committee of the International Association of Meteorology and Atmospheric Sciences(IAMAS-CNC)organized an online Nobel Prize interpretation workshop.Over 400 participants attended the online workshop,and more than 120000 parti-cipants watched the replay.  相似文献   
93.
Molecular biomarkers are among the most sensitive and earliest responses to pollutants. However, lack of detailed knowledge on variability of responses and their possible seasonal variation limit their use. In addition, the seasonality of biological processes modulates the response of organisms to pollutant stressors. Using multivariate statistics, we have studied the influence of environmental and biological factors on the response of a battery of molecular biomarkers in the clam Chamaelea gallina collected along the South-Spanish littoral. Multivariate discriminant analysis clearly distinguished biomarker response between clean and polluted areas, using heavy metals as indicator of pollution. Such differences disappeared when the dataset was normalised for metal content, thus indicating that pollution was the main significant cause of the changes observed between clean and polluted sites. In conclusion, this work shows that, when applying a complete biomarker panel, multivariate statistical tools can be used to discern pollutant- from non pollutant-related responses.  相似文献   
94.
95.
川滇两省水能资源开发量位居全国前茅,尤其是川滇交界区域的雅砻江、大渡河、金沙江流域的水能资源富甲全国,在西部大开发中的战略地位极其重要,国家即将在此建成一个位于全球破坏性地震多发区域的巨型水库密集区。具有全球难寻的监测、预报、研究水库地震的资源优势。建议用完全开放的创新思维,在此区域创建水库地震监测预报研究实验场,具有重要的防震减灾现实意义和历史意义。  相似文献   
96.
The contents of As, Cd, Cu, Cr, Mg, Mn, Ni, Pb and Zn have been determined in sediment and water samples from Valle de las Garzas estuary and Port Manzanillo (Colima, Mexico) using ICP-AES. The concentrations of these elements were used for a comparative study to determine the distribution of heavy metals and to evaluate which elements reflect natural or anthropogenic backgrounds. For this purpose, seven sampling points were selected: Four of them correspond to the lagoon, and three were situated in the port. Statistical analysis of the mineral content was assessed. Initially, data comparison was assessed by statistical tests for each variable. Principal component analysis was then applied considering the influence of all variables at the same time by obtaining the distribution of samples according to their scores in the principal component space. In this way, four studies were carried out: (1) study of sediments collected during the dry season; (2) study of sediments collected during the rainy season; (3) comparative study between sediments from rainy and dry season; and (4) study of water composition collected during rainy season. From the results of the performed analyses, it can be concluded that metals distribution pattern reflected natural and anthropogenic backgrounds (e.g., sediments from the lagoon, situated at the beginning of the rain channel, presented high contents of Zn and Cu, perhaps related to anthropogenic activities or the influence of igneous sediments).  相似文献   
97.
喀腊大湾地区位于阿尔金山脉东北缘,当地早古生代时期构造环境复杂并且伴随剧烈的花岗质岩浆活动.通过对区域内早古生代中酸性侵入岩5个岩体(大平沟岩体、阿北银铅矿岩体、阿北岩体、4337北花岗岩体、喀腊大湾南岩体)的岩石学、岩相学、地球化学特征研究,探讨早古生代区域重大构造事件和构造环境.南部的喀腊大湾南岩体表现低钾性质,其余4个岩体样本为中高钾钙碱性中酸性岩,并且有向高钾演变的趋势,铝饱和指数在1.0~1.1之间,数据统计和分析大部分样品具有I型花岗岩特征,少部分显示了I型向S型过渡的性质,代表了洋壳-陆壳活动性大陆边缘的环境.结合喀腊大湾周边地质背景,本地区应该是阿尔金古洋壳和塔里木地块南北向碰撞作用的火山岛弧区域.  相似文献   
98.
随着人们生活水平的提高,对室内污染越来越关注,应"中国室内环境监测委员会"提出的需求,通风气象指数于2006年6月首次向北京公众发布,文章就首先研发并投入业务使用的夏季通风指数给出了详细论述.通过对2005年夏季(6~8月)的各气象要素(气压、温、湿、风、能见度、天空状况等)资料共1790个数据做检验分析,最终选取体感温度为主要预报因子并综合考虑夏季特殊天气条件和风力以及污染的影响,得出夏季通风指数在一天中7个时段的预报公式,并划分出相应的指数等级.  相似文献   
99.
地下工程施工监控地质地理信息系统研究   总被引:1,自引:0,他引:1  
曾立斌  黄牧  戎晓力 《岩土力学》2010,31(Z1):342-348
主要设计与实现了地下工程施工监控地质地理信息系统(MGGIS)。首先分析了系统特点、结构、具有的功能以及采用的平台和相关技术,定义了数据的获取和存储格式。然后在此基础上进行了3个功能独立的子系统的详细设计与实现,分别为工程计划显示子系统、平面时空效应子系统和断面图显示子系统。首次提出在RIA技术支持下,实现B/S架构下的工程地质地理信息系统;提出了反映随施工进度变化地下工程及环境空间信息的显示平台技术方案,充分反应了地下工程施工中空间信息具有时空效应的特点,适合地下工程安全风险管理的需要。该系统与同类型地理信息系统平台相比具有使用简单、交互性强、速度快等优点,研究成果已经在北京轨道交通工程安全风险监控系统和南京地铁工程安全风险监控系统等相关项目中得以应用。  相似文献   
100.
Chemostratigraphic concepts postulate that distinct chemozones could be recognized from rock records to help correlate geographically separated strata. Many studies have upheld this view, but were limited to classic boundaries such as Cenomanian–Turonian or Cretaceous–Tertiary. Only a few elements and isotopic compositions were made use in such studies. An attempt to recognize chemozones of Barremian–Danian strata of the Cauvery Basin, South India through whole-rock chemistry had revealed many complex signals and depositional events as expressed by bulk geochemical profiles. The signals indicate major shift in sedimentation pattern from dynamic depocenter to stable depositional conditions during Santonian. Varying sensitivities of different elements towards prevalent depositional conditions are also inferred. Trends of geochemical composition indicated domination of single depositional control all through the depositional history, basinal configuration that limited terrestrial sediment source and episodic influx of detrital materials. Presence of distinct change in whole-rock geochemistry across geochronological and lithostratigraphic boundaries is deciphered through a statistical tool ANOVA. These results demonstrate that visual delineation of chemozones in a long ranging rock record would be tenuous and has to be exercised with caution.  相似文献   
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