宗日遗址人骨的稳定同位素分析   总被引：5，自引：0，他引：5  

崔亚平  胡耀武  陈洪海  董豫  管理  翁屹  王昌燧 《第四纪研究》2006,26(4):604-611

利用C和N稳定同位素分析方法研究了青海宗日遗址先民的食谱,探讨了先民的经济模式以及食谱变化趋势。所有人骨骨胶原中的C,N含量以及C/N摩尔比,均表明样品保存较好,可用作食谱分析。骨胶原的δ¹³ C值和δ¹⁵ N值分析显示,先民主要以C₄类植物为食,也摄取一定量的肉食,反映了以粟、黍等为主食而渔猎为辅的生活方式。性质未明墓葬与宗日墓葬之间存在的较大食谱差异,可能与其来自不同文化密切相关。宗日遗址在发展过程中,先民食谱中C₄植物增加而肉食类减少,反映了农业加狩猎采集的混和经济模式向稳定农业模式转变的趋势。  相似文献   

藏南拉康温泉地质特征及雄曲河谷两岸地热分布不均成因分析     

石圣  赵德军  蒋祥  翁新海  陈伟 《矿物岩石》2021,41(1):106-115

西藏山南地区洛扎县雄曲河拉康段在600 m距离内出露温泉4处,仅1处位于河谷右岸;平硐勘查显示两岸岩性、产状、构造一致,地热异常却仅在左岸平硐内部显著,右岸平硐地热异常不明显.本次研究以此异常为出发点,通过片麻状花岗岩不同切面导热实验、片麻状花岗岩与板岩相同切面导热实验,温泉水δ2H,δ18O同位素测试分析等方法,探究...  相似文献   

Optimal lake-marsh pattern determination in lake-marsh systems based on the eco-hydrological processes management     

Wuxia Bi  Baisha Weng  Denghua Yan  Meng Li  Zhilei Yu  Lin Wang  Hao Wang 《水文研究》2020,34(26):5260-5277

The major hydrological factors in lake-marsh systems are water level (depth), water surface area, and water volume. The key index for determining the lake-marsh pattern is water level, which leads to the variation of lake-marsh patterns under natural hydrological alternations. In addition, the vegetation structure also affects the lake-marsh pattern. With socioeconomic development and climate change, the ‘land use’ and ‘water use’ competitions appear more seriously between a lake-marsh system and its surrounding socioeconomic system, also inside the lake-marsh system. The possible optimal lake-marsh pattern could solve the contradictions mentioned above. As few studies focus on this issue, this study proposed an optimal lake-marsh pattern determination method with eco-hydrological management on relieving the land use and water use competitions. The optimal lake-marsh pattern determination method considers the protection objects (water depth demands), water supply (precipitation, surface water, and groundwater), and water demand (especially evapotranspiration) in the system at annual and monthly scales. Calculation and analysis were performed for the optimal pattern of the Wolonghu Wetlands as an example. The results mainly showed that the lake-marsh pattern of the Wolonghu Wetlands cannot be achieved on meeting both the maximum ecological services values and minimum water shortage amount under present natural condition. With artificial regulation measures, the possible optimal annual lake-marsh patterns can be obtained based on both ecological and hydrological objectives, with the area ratio of lake and marsh in the range of 0.650:0.350 and 0.726:0.274, the corresponding water level of lake body was of 86.85 to 87.0 m. This study could provide references for the Wolonghu Wetlands management, also for similar lake-marsh systems and other ecological systems.  相似文献   

我国大气透明度系数的时间变化     

方先金  翁笃铭 《地理学报》1988,(1)

作者在文献[1]中探讨了我国大气透明度系数的空间分布及其主要影响因子。本文则探讨大气透明度系数的时间变化,特别是它的长期变化及其成因。结果发现:火山爆发可使大气透明度系数明显减小;由于人类活动影响,冬季大气透明度系数P_2、P_d有明显的减小趋势,P_2、P_d与用煤量等污染指标有很好的负相关。文中还对大气可降水含量的气候学推算方法进行了探讨。本文应用1820—1983年的地球自转变化率资料,分析出地球自转变化存在准44个月、准11年、准24年和准49年的周期。南方涛动指数的变化,大气活动中心位置的移动,赤道东太平洋海温的异常等,都能从地球自转速度变化思期中找到关系。已经发现,在地转长期(准24年和准49年周期)加(减)速时,南方涛动指数减弱(增强),大气活动中心向西北(东南)移动,非洲干旱区降水偏多(偏少);同时发现:在地转短期(准44个月周期)加(减)速时,赤道东太平洋海温降低(升高)。  相似文献   

On the Taiwan Warm Current Water     

翁学传  王丛敏 《中国海洋湖沼学报》1988,6(4):320-329

With the use of historical data from their 1982-1985 special observation at the source area of the Taiwan Warm Current the authors conducted studies to clarify the temperature and salinity characteristics, variability, and origin of the Taiwan warm Current Water, and its influence on the expanding direction of the Changjiang Diluted Water.The main results are given below.(1)The Taiwan Warm Current Water can be divided into the "Surface Water of the Taiwan Warm Current" formed due to the mixing of the Kuroshio Surface Water flowing northward along the east coast of Taiwan with the Taiwan Strait Water, and the "Deep Water of the Taiwan Warm Current" originated from Kuroshio Subsurface Water to the east of Taiwan. It is characterized by stable low temperature and stable high salinity in summer. The maximum seasonal variation and maximum secular variation of temperature and salinity are 1.87℃, 0.26‰ and 2.96℃, 0.37‰, respectively.(2)The variation in strength of the Taiwan Warm Current is the main influe  相似文献   

Accumulation discrepancy of heavy metal and organic pollutants in three near-shore depositional environments, southeastern China     

Huan-Xin Weng  Yang-Ming Zhu  Ya-Chao Qin  Jian-Yu Chen  Xun-Hong Chen   《Journal of Asian Earth Sciences》2008,31(4-6):522-532

Heavy metal and organic pollutants in sediments along the coastal zone of southeastern China have been investigated. Sediment samples are retrieved from three depositional environments: coast, estuary, and tide-affected river mouth. The relative abundance of heavy metal and organic pollutants is related to their geochemical properties as well as depositional environments and anthropogenic discharge. Based on a sequential extraction method, it is revealed that anthropogenic Pb, Cr, Cu, and Cd are mainly bound to Fe–Mn oxides, suggesting that adsorption and co-precipitation of Fe–Mn oxides are in the control of their transfer processes from water column to sediment. Heavy metal bound to carbonates is also an important pool especially for Cd, Mn, and Pb. The main organic pollutants found in the study area include petroleum-related alkanes, phthalic acid ester, organic silicon, chlorophenol, phenyl ether, and amine. The accumulation of heavy metals and organics in surficial sediments has a decrease tendency from estuarine environment to coastal environment and to tide-affected river mouth.  相似文献   

CLIMATIC CHARACTERISTICS OF ATMOSPHERIC NET RADIATION OVER CHINA_*     

Weng Duming  Gao Qingxian  Yao Zhiguo 《Acta Meteorologica Sinica》1997,11(2):246-254

In terms of ERBE and ISCCP data.and measured/calculated surface net radiation,computation is performed of the climatic characteristics of ANR(atmospheric net radiation) across China alongside with the discussion and relations to other two kinds of radiation and contributing factors.Evidence suggests a high linear correlation of ANR with atmosphere-absorbed shortwave radiation.whereby can be established a general expression for ANR,which decreases more sharply as a function of altitude and increases slightly with latitude in summer,and changes uniformly in winter.Eventually,a comparison is made of the findings presented in this paper and literatures regarding the ANR pattern and magnitudes,indicating their great difference.  相似文献   

THE CALCULATION AND ANALYSIS OF SLOPE NET RADIATION IN CHINA^*     

Weng Duming  Sun Zhi''an  Shi Bing 《Acta Meteorologica Sinica》1991,5(2):242-251

By using the climatological calculating method for each component of slope surface net radiation proposed by the authors,calculations and analyses are done of the distribution features of slope net radiation in China with emphasis on the discussion of variations of slope net radiation in typical stations and sites with slope direction,slope,latitude and season.The distribution features of net radiation on the north and south slopes are,for the first time,mapped and discussed,revealing the great difference on the national basis,and thus acquiringa new interesting result that the negative-value area of winter net radiation on the north slope(20°)can reach Yunnan and Guizhou Provinces and middle and upper reaches of the Changjiang River.  相似文献   

中国坡地太阳直接辐射分布特征     

孙治安  史兵  翁笃鸣 《高原气象》1990,(4)

本文经简单变换将坡地太阳直接辐射计算式化为S_(αβ)=K(αβ)·S＇,其中S＇为水平地面太阳直接辐射日平均辐照度;K_(αβ)为坡地直接辐射换算系数。文中着重分析了K(αβ)随坡向、坡度、纬度和季节的变化特征,给出了计算南、北坡最热坡度的表达式。最后计算出我国211个站点全年各月坡地太阳直接辐射日平均辐照度,并以南、北坡20°为例分析讨论了坡地太阳直接辐射地理分布特点。  相似文献   

海南岛海风演变特征的观测分析   总被引：4，自引：1，他引：3  

王静  苗峻峰  冯文 《气象科学》2016,36(2):244-255

本文利用2012年海南岛19个常规气象站、5个海岛站的逐时资料以及海口站的探空资料,对海南岛海风的时空演变特征及在不同天气条件下海风发展的特征进行了统计分析,结果表明:2012年全年海南岛的海风多发生于春、秋季,频率分别为40%和33%,冬季最少(约为19%),尤其是一月,大部分站点均不足10%。夏季海风出现时刻较早;南部沿海海风结束时间晚于北部沿海;冬季海风开始得较晚,南部海风结束时间早于北部沿海。海风平均持续时间约为10 h。沿海站的海风风速主要集中在3~6 m·s~(-1),且最大风速值出现在春季,除琼山、海口站外,最大海风强度多出现于春夏季。内陆站中部山区附近海风出现频率较高、开始时刻较早、持续时间较长、强度也较大。海风向内陆的传播距离至少为70 km;海风易发生在阴天,其次为多云天气,少云日的海风最少。  相似文献