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91.
The relationship between the spring bloom along the Primorye coast and the sea ice of the Tatarskiy Strait in the northern region of the East/Japan Sea, a semi-enclosed marginal sea in the North Pacific, was investigated using the ten-year SeaWiFS chlorophyll-a concentration data and DMSP/SSMI sea ice concentration data from 1998 to 2007. Year-to-year variations in the chlorophyll-a concentrations in the spring were positively correlated with those of the sea ice concentrations in the Tatarskiy Strait in the previous winter with a correlation coefficient of 0.77. Abrupt increases in nutrients, essential for the spring bloom in the upper ocean during spring, were supplied from sea ice-melted waters. Time series of vertical distributions of the nutrients indicated that phosphate concentrations were extremely elevated in the upper ocean (less than 100 m) without any connection to high concentrations in the deep waters below. The water mass from sea ice provided preferable conditions for the spring bloom through changes in the vertical stratification structure of the water columns. Along-coast ratios of stability parameters between two neighboring months clearly showed the rapid progression of the generation of a shallow pycnocline due to fresh water originating from sea ice. This study addressed the importance of the physical environment for biogeochemical processes in semi-enclosed marginal seas affected by local sea ice. 相似文献
92.
选取贵州西部六枝特区郎节坝试验区、钟山区大地试验区、水城县前进试验区和盘县坡上试验区共4个不同海拔马铃薯种植区连续6 a(2006—2011年)春薯主要大田生长期(2—9月)逐日降水的观测资料和春薯产量资料,利用降水产量积分回归函数,分析降水变化对春薯产量的影响。结果表明,贵州西部山区降水存在时空分布不均状况,但降水总体呈现出随着海拔高度的升高而增多趋势,同时找出了影响春薯产量不稳定的主要原因。不同区域春薯生长发育过程中的最佳补充灌溉时期不同:郎节坝试验区在播种期到开花期需补充灌溉,大地试验区应分别在播种期和现蕾期到开花期补充灌溉,前进试验区在现蕾期到开花期需补充灌溉,坡上试验区应在开花的始期至盛期补充灌溉。科学、合理的调控措施,有利于提高春薯的产量和质量。 相似文献
93.
94.
钱会 《地球科学与环境学报》1989,(1)
本文以华清池泉水化学成分为例,采用水—岩化学平衡计算的方法,进行了热储温度估算。根据9种矿物平衡温度的统计结果,得出华清池温泉深部热储温度为53.44±6.11℃。这和温泉附近几个热水孔的温度测定结果是基本一致的。 相似文献
95.
钱会 《地球科学与环境学报》1987,(3)
本文在参阅Crerar D.A.等人的资料的基础上,比较系统地论述了水溶液中各种化学组分可能存在形式分配及Eh值的计算方法。文章从对施实计算所需的原始数据的说明开始,主要从以下几个方面说明了计算方法:1.热力学问题的数学描述;2.问题的数值解;3.活度系数的校正;4.迭代步骤;5.Eh值的计算。文中以华清池温泉水化学分析资料为例,分别给出了此资料在12℃和42℃时的计算结果。由于分析技术和计算方法的误差,Eh值的计算结果存在一定的偏离,这也可能是由于给定温度下水中某些组分间存在着非平衡而引起的。 相似文献
96.
A field study was conducted to assess variations in physico-chemical characteristics of water of the springs located within
the boundary of a Central Himalayan town where the springwater is used for drinking purposes. Monitoring of 12 springs was
carried out for three seasons (winter, summer and monsoon). The results indicate direct influence of unplanned sewage disposal
on the springwater quality as reflected by significant regional variations in the concentration of nitrates, chlorides, sulfates,
sulfides and electrical conductivity. Population density varies within the town from 3110 to 14 137 persons/km–2 and has direct relationship with water quality. Springs located in the densely populated area had higher concentrations of
all these compounds. Concentrations of nitrates up to 60 ppm were observed in some springs, making water unsuitable for human
consumption. No significant changes were observed in springwater quality during different seasons.
Received: 3 February 1995 · Accepted: 27 February 1996 相似文献
97.
Study on urban construction planning based on karst landscape protection contributes to sustainable development of urban construction in karst area. Jinan is a city famous for karst spring water. Karst landscape plays a decisive role in urban construction. Through hydrogeological analysis, the distribution characteristics of karst mountain, cave, gully and flat dam in Jinan are analyzed. It is revealed that various karst landforms are involved in the spring circulation process to varying degrees. Some karst landforms have been destroyed in the process of urban construction and the karst landscape has been overexploited resulting in the direct or indirect weakening of spring water recharge and infiltration capacity and the decrease of spring water flow. Through the study of the principle of organic combination of karst landscape and urban construction planning, on the basis of protecting the ecological environment of the south, paying attention to the overall protection of the karst geomorphology system and the principle of accessibility of the karst landscape, the development countermeasures guided by urban planning are put forward based on karst landforms protection. On the basis of fully considering the special karst landform conditions in Jinan, the countermeasures are that the ecological control red line of urban construction planning should be set up based on karst mountains and valleys in southern of Jinan City. It is suggested that the bare carbonate rock continuous mountain foot line in the direct recharge area should be taken as the south control red line of urban development and included in the overall planning. The urban landscape is mainly displayed in the main axis based on karst mountains and springs, constructing East-West Axis-characteristic Landscape Belt along the Wufeng Mountain-Langmao Mountain-Hero Mountain-Qianfo Mountain-Long cave-Panlong cave-Jinping Mountain line and North-South Axis Landscape Belt along the Baotu Spring- Qianfo Mountain line, Baiquan-Panlong cave line, Baimai spring-Dajian Mountain line. Based on the karst river valleys and the river system, the urban spatial pattern is constructed, forming ecological corridor, restoring infiltration function of river. The form of urban construction should be shaped based on karst landform and the river system. The main form is semi-star like radiation type and the combination of central intensive type and zonal type. Based on the whole protection of karst geomorphology system and the scientific molding of karst landscape, the ecological landscape city with the symbiosis of spring and urban can be built. 相似文献
98.
《Chemie der Erde / Geochemistry》2015,75(3):287-300
The chemical and isotopic characteristics (oxygen, hydrogen, and strontium) of spring waters and isotopic compositions of helium (He) and neon (Ne) in gases escaping from spring waters in the Lanping–Simao Basin are studied. A total of twenty-one spring water samples (twelve hot springs, four cold springs, and five saline springs) and eleven gas samples were collected from the study area, including one spring and one gas sample from northern Laos. It is found that saline spring waters in the study area are of chloride type, cold spring waters are of carbonate type or sulfate type, and hot spring waters are of various types. High total dissolved solids levels in saline springs are significantly related to Upper Cretaceous–Paleocene salt-bearing strata. On the basis of hydrochemical geothermometry, the reservoir temperatures (Tr) for hot springs, cold springs, and saline springs are 65.5–144.1, 37.8–64.4, and 65.1–109.0 °C, respectively, and the circulation depths of saline springs are much larger than those of hot and cold springs. The oxygen and hydrogen isotopic compositions of springs in the Lanping–Simao Basin and northern Laos are primarily controlled by meteoric waters with obvious latitude and altitude effects, and are also influenced by δ18O exchange to some extent. Most Sr2+ in spring waters of the study area is derived from varied sources (carbonate, evaporite, and silicate mineral dissolution), and the Sr isotopic compositions are greatly influenced by volcanic rocks. Wide distribution of crust-derived He in the Lanping–Simao Basin and northern Laos reveal that faults in these areas may not descend to the upper mantle. It is concluded that water circulation in the study area may be limited above the upper mantle, while saline springs may originate from the Upper Cretaceous–Paleocene evaporites. Hydrochemical characteristics demonstrate affinities among the Lanping–Simao Basin, northern Laos, and Yanjing, eastern Tibet, while disaffinities are observed between these areas and Tengchong on the basis of the hydrochemical characteristics and noble gas isotopic compositions. 相似文献
99.
100.
Discontinuous tephra layers were discovered at Burney Spring Mountain, northern California. Stratigraphic relationships suggest that they are two distinct tephras. Binary plots and standard similarity coefficients of electron probe microanalysis data have been supplemented with principal component analysis to correlate the two tephra layers to known regional tephras. Using principal component analysis, we are furthermore able to bound our uncertainty in the correlation of the two tephra layers. After removal of outliers, within the 95% prediction interval, we can say that one tephra layer is likely the Rockland tephra, aged 565–610 ka, and the second layer is likely from Mt. Mazama, the Trego Hot Springs tephra, aged ~ 29 ka. In the case of the Rockland tephra, the new findings suggest that dispersal to the north was highly restricted. For Trego Hot Springs ash, the new findings extend the distribution to the southwest, with a rapid thinning in that direction. Coupled with considerations of regular tephra dispersal patterns, the results suggest that the primary dispersal direction for both tephras was to the south, and that occurrences in other directions are unlikely or otherwise anomalous. 相似文献