对江苏胥溪河成因及其开发利用的新探讨

Along the north bank of the Xuxi River, the sand-intercalated-muddy gravel layer from -3.7 - -5.8 m in the borehole 7508 at the East Dam and the middle, coarse and fine sand layer with a thickness of 4.5 m at the lower part of the borehole 8179 between the East Dam and the West Dam indicate that a large natural river was here before the Kingdom of Wu excavated the Xuxi Canal. The existence of Neolithic sites such as Xuecheng, Chaoduntou and Xiajiadang along the Xuxi River and the silt layer with dozens of meters archived under the earth＇s surface within a range of 1 km along both banks are the even more important evidences for the existence of the ancient Zhongjiang River. The floodgate of the East Dam nowadays makes against the communication between the Shuiyangjiang River and the Taihu Lake. The authors suggest the canal between Wuhu and Taihu Lake should be excavated as soon as possible, namely, the navigation channel from Wuhu through Guchenghu Lake, Xuxi River, East Dam, Liyang, Yixing to Taihu Lake should be further widen and the deposits composed of slope wash on the watershed between Shuiyangjiang River and Taihu Lake should be dredged away. Then, the channel journey can be shortened, the boats in ship transportation on the Yangtze River can be shunted to ensure the security of shipping, the resources of sand and gravel in the old river channel can be exploited and the dike of the Yangtze River can be reinforced. So, the problems of irrigation, flood diversion, pollution abatement and drainage of flooded fields in the lower Yangtze River will be resolved. Then, the above methods can impel the sustainable development of the Xuxi River and Taihu Lake area.     

末次冰期间冰阶晚期长江中游风尘堆积及环境意义

定山砂山剖面的下层灰黄色土-淤泥沉积，为末次冰期间冰阶（40～22kaBP）区域降尘堆积。灰黄色土层与淤泥为同源异相沉积，粒度组合基本相同，无特征性差异。频数曲线都以双峰为特征，第一峰为主峰，众值8～32 μm；第二为次峰，众值250～500μm。9.75±0.25Φ~4.25±0.25Φ(1 ~62.5μm)在垂向上具有相似的线形变化，组成第一峰态，各粒级垂向上的含量变化是区域冬季风强弱变化的敏感指标；2.25±0.25Φ ~-0.75±0.25Φ (180~2000 μm)具有相似的线形，组成第二峰态，各粒级剖面含量变化则揭示了冬半年环境干湿状况与局地尘暴事件。在对应区域降尘堆积较弱的两个时段，存在局地尘暴的增强事件，指示局地冬半年环境干燥。     

皖南花山石窟群开凿年代地衣测年及成因

据在花山石窟地区古代桥梁、桥垛、牌坊、墓碑、古民居、古房基和石窟洞壁洞口量测出的96个黄绿地图衣最人内切圆直径，测定出花山石窟主要开采年代为距今515～370年即明代中晚期(公元1477～1632年间)，石窟岩性与周边地区古建筑岩性的比较以及史料记载和石窟中遗留的古代瓷器残片年代均能证明这一点。鉴于石窟地衣量测工作主要在石窟洞口进行，由此推测石窟深处开采时代可能延续至清代。     

中坝遗址约4250a B．P．以来古气候和人类活动记录

重庆中坝遗址地层Rb、Sr、Hg及TOC研究表明：Rb、Sr和Rb／Sr值较好地反映了约4250aB．P．以来气候变化过程,主要干冷期可与敦德冰川δ^18O曲线谷值、湖光岩沉积物磁化率和Ti曲线峰值、以及大气^14C浓度峰值和太阳活动水平较长期变化的低谷对比,反映出地层中Rb、Sr不易受人类活动干扰的特性。结合考古遗存对比还发现,Hg、P、Ca、Mg和TOC记录了该遗址约4250aB．P．以来人类活动的三个不同演变阶段。进一步研究认为,盐业遗址的衰落可能与洪水事件、盐泉资源的过度消耗以及由此造成的利用难度加大有关     

河南地区全新世环境考古研究进展及未来趋势

河南地区是中国文明起源的核心区域之一,史前文明璀璨发达,是开展全新世环境考古研究的理想区域。近二十年来,河南地区环境考古研究中,文化演化的环境背景分析成果突出,灾变事件影响及人类对环境变化的响应研究亦有涉及,数字环境考古工作也开始逐渐起步。但在河南地区仍缺少高分辨率古环境重建方面的研究,且已有环境考古研究多关注环境变化对文明演化的影响,而在人类活动对环境变化响应及其环境效应方面研究尚显不足。此外,随着RS、GIS等技术应用的不断深入以及对景观考古的不断关注,考古遗址预测模型以及史前人与自然关系的定量和模拟研究已成为当前国际环境考古研究的热点。     

中坝遗址地层的Cr/Cu值对干湿环境的指示意义

将中坝遗址5ka以来连续沉积地层按文化序列分为12层,分别测量Rb、Sr和Cr、Cu含量,对比显示,Cr/Cu比值与Rb/Sr比值明显正相关。Cr与Rb的属性相似,Cr化学活性低,易于在粉砂质沉积物中富集;而Cu和Sr在成壤过程中容易迁移,在粘土质沉积层中含量较高。通过对Cr、Cu元素在表生环境下的化学性质、沉积地层的属性、微地貌特征、与泥炭腐殖化度古里雅冰芯氧同位素曲线等指标对比表明,Cr/Cu比值变化对环境干湿变化的指示具有普遍意义。     

湖北旧石器至战国时期(1.15MaBP-278BC)古文化遗址分布与环境演变(英文)

A total of 1362 archaeological sites from the Paleolithic Age to the Warring States time in Hubei Province increase gradually from west to east and from high land to low land.The number of Paleolithic sites with altitude of 50-500 m account for 78% of the whole,while 71%-95% of sites from the Neolithic Age to the Warring States time mainly distribute at the areas of 0-200 m.The temporal-spatial distribution of archeological sites in this area is affected by two factors.For one thing,the human beings of every period need to choose the first or the second terrace as living sites which are near water source and are easy to withstand flood.Additionally,affecting by the regional tectonic uplift since the Holocene,down cutting of rivers can form new river valley,and lateral erosion and accumulation of river in stable time of tectonic movement can result in increasing of many new terraces.So,the human beings migrated to adapt to the change of terrace location,leading to the sites increase gradually in the lower areas of the central and eastern parts of this province.For other things,the temporal-spatial distribution of archeological sites in this area is affected by the climate condition.The Paleolithic sites mostly distribute in the Hanshui River Valley in northeastern Shiyan,southeast of Jinzhou and east of Jinmen,which is because rivers distributed in higher areas in this period.During the Chengbeixi Culture period,the sites are rare in the quondam Paleolithic sites distribution area,but increase obviously along the Yangtze River near the southwest Yichang.The spore-pollen record of Dajiuhu Basin indicates that only 23 Chengbeixi cultural sites may be related to more precipitation and flood during the Holocene wet and hot period.The Daxi Culture,Qujialing Culture and Shijiahe Culture are corresponding to middle and top of the Dajiuhu spore-pollen Zone Ⅳ,during which the climate is in order as a whole and is propitious to agricultural development.In the Qujialing Culture period,32 of original 34 Daxi cultural sites disappeared,while 90 sites increase abruptly in the higher highlands in the north of Xiangfan-Jinmen-Xiaogan,which may respect with enlarging of water areas.The Chu Culture period is corresponding to Dajiuhu spore-pollen Zone V,which is in warm and dry Holocene phase,but it seems that the climate condition is still propitious to agricultural cultivation and the number of archeological sites increase heavily to 593.In addition,there are the least archaeological sites in the lake areas of southeast Hubei Province because of low-lying topography with altitude of 0-50 m and the severest flood.     

罗布泊地区自然环境演变及其对全球变化的响应

罗布泊于1962年全部干涸,干涸前湖面积约5400km2,目前湖底被厚20～40cm的盐壳覆盖,海拔约780m。盐湖北岸和东岸普遍发育三级湖积台地,其高度分别为783～785m,789m和810～820m,相应的湖面积分别为9250km2,20000km2和55000km2左右,根据释光和14C年代,它们分别形成于7.0～7.5kaB.P.,约30kaB.P.和90～130kaB.P.,与深海氧同位素第5和3阶段及全新世大暖期在时间上具有很好的对应关系。可见,位于亚洲腹地、气候极端干旱的罗布泊,在地质历史时期其湖面的扩张与收缩受全球气候变化因素驱动,其变化幅度的强弱则与区域环境因素有关。     

南京地区下蜀黄土磁性地层年代与古环境变化

通过对南京江北泰山新村下蜀土剖面所采的144个样品和南京江南燕子矶下蜀土剖面所采的467个样品所进行的古地磁测年、磁化率测量和粒度测定,建立了南京地区下蜀黄土地层220kaB.P.以来较精细的时间标尺;在此工作基础上,将南京下蜀黄土堆积所记录的环境信息同北方经典黄土、深海沉积氧同位素记录进行了对比,发现燕子矶剖面磁化率曲线能够与深海沉积氧同位素曲线1—7阶段进行良好的对比,两者之间的细节变化具有一致性,其中S0表现为高值,可与氧同位素曲线阶段1对比,为一高温期;L1可以划分为两层黄土(L1LL1、L1LL2)和一层弱发育的古土壤(L1SS1),L1LL1和L1LL2可与阶段2和4对比,L1SS1可与阶段3对比;S1古土壤层由3个古土壤亚层(S1SS1、S1SS2、S1SS3)和2个弱成土亚层(S1LL1、S1LL2)叠置而成,磁化率曲线具有明显的三峰夹两谷形式,正好可与氧同位素阶段5对比,表明这一时期的古气候特点是在湿热的背景下有两次干冷波动,其中S1SS1、S1SS2、S1SS3分别对应于5a、5c、5e,S1LL1、S1LL2对应于5b、5d;L2黄土磁化率曲线整体呈谷形,但中下部有一次峰,下部磁化率偏高,与阶段6的曲线特征相吻合;S2古土壤层未见底,目前获得的磁化率曲线特征可与7a和7b对比。以上研究结果确立了江南风尘堆积的古气候全球变化意义。     

长江三峡中坝遗址地层中Rb和Sr的分布特征及其古气候演变

长江三峡中坝遗址是我国目前仅有的、世界上也罕见的“通史式”遗址。它不仅蕴藏大量的文化内涵,而且包含极其丰富的自然环境演变信息,是研究三峡地区全新世环境演变的理想剖面。文章对遗址地层中的铷(Rb)、锶(Sr)值进行了测试和分析,结果显示:剖面地层中的Rb含量偏低,而Sr含量偏高,Rb/Sr比值变化较大。Rb/Sr比值已成为区域环境演变研究中较理想的替代指标,根据Rb/Sr比值的环境指示意义发现,长江三峡地区全新世中晚期以来气候环境总体上逐渐趋于恶劣;气候冷暖湿热变化剧烈;寒冷期长于温暖期,并没有明显地向湿热方向发展趋势。与长江下游等东部其他地区相比,长江三峡地区也存在明显不同之处:隋唐暖期不明显,而中世纪暖期表现显著。