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| 1 | 草海地区过去500年来古温度重建:来自沉积物纤维素结合碳酸盐氧同位素的证据显示文摘利用连续流同位素质谱仪测定了草海沉积物柱芯碳酸盐和纤维素氧同位素比值.依据纤维素和湖水氧同位素之间稳定的分馏值定量恢复了历史时期草海湖水氧同位素组成,在此基础上结合碳酸盐氧同位素组成,运用Craig方程恢复了草海地区过去500年来古温度变化历史.结果表明恢复的1950年以来的温度变化与草海地区获得的气温记录(年平均)具有很好的一致性;草海地区在过去500年存在四个明显的冷期:1540~1570 AD,1670~1715 AD,1780~1870 AD及1900~1930 AD,其中前三个冷期发生在传统意义上的现代小冰期时段.重建的四个冷期与邻近地区泥炭、冰芯、树轮、历史文献及湖泊沉积记录的冷期基本一致,特别是与西南地区红原泥炭纤维素氧同位素记录的温度变化曲线相吻合;恢复的草海地区过去500年古温度变化曲线与印度夏季风变化及太阳活动强度有较好的一致性,其中1670~1715 AD和1780~1870 AD冷期分别对应于Maunder和Dalton太阳活动极小期.这些结果表明纤维素氧同位素结合碳酸盐氧同位素是一种有效的古温度指示剂,同时也为现代小冰期在中国西南地区的存在提供了直接证据. | 朱正杰 陈敬安 曾艳 | 2014 | 中国科学:地球科学2014，44，2： | 15 |
| 2 | 云南程海湖泊生态系统演化的摇蚊亚化石沉积记录显示文摘通过对程海沉积岩芯摇蚊亚化石组合的分析,结合210Pb、137Cs年代测定和沉积物TOC、TN、粒度指标,探讨了近200年来程海摇蚊属种组合变化及其对湖泊环境演化过程的响应,揭示了人类活动对湖泊生态系统的影响。结果表明:1920年之前,程海营养水平较低,摇蚊属种组合以Procladius sp.为主;1920至1990年,Procladius sp.逐渐减少,而耐营养种Chironomus plumosus-type增加,营养水平上升;1990年末期后,受农业化肥使用、藻类养殖等人类活动的影响,湖泊营养水平显著增加,Procladius sp.相对丰度急剧减少,而Chironomus plumosus-type急剧增加,取代Procladius sp.成为优势种。程海近200年沉积记录研究表明1970年前湖泊的环境状态基本接近人类干扰前的状态,可作为该湖科学管理与治理的基准环境。 | 陈静逸 张恩楼 | 2015 | 生态科学2015，34，2： | 4 |
| 3 | Paleotemperature variations at Lake Caohai, southwestern China, during the past 500 years:Evidence from combined δ^(18)O analysis of cellulose and carbonates显示文摘The oxygen isotopic values of aquatic plant cellulose and carbonates in Lake Caohai sediments were measured using a continuous flow isotopic ratio mass spectrometer(CF-IRMS).Because of predictable oxygen isotopic fractionation between cellulose and its source water,the oxygen isotopic composition of paleo-lake water has been established quantitatively.Combined oxygen isotopic values of cellulose and carbonates were used in the‘Craig’equation to determine paleotemperatures and their variation in the lake during the past 500 years.Results show that the paleotemperature trend correlates well with meteorological records from Weining.There are four notable cold intervals at Lake Caohai over the past 500 years,namely 1540–1570AD,1670–1715AD,1780–1870AD and 1900–1930AD,and the former three cold intervals have been observed in the conventional Little Ice Age(LIA).These cold periods at Lake Caohai correspond well with those recorded from tree ring,peat,and ice core data from adjacent regions,particularly temperature those inferred fromδ18O of peat cellulose from Hongyuan Southwestern China.The trend in paleotemperature variations at Lake Caohai are also consistent with both the change of Indian summer monsoon,derived fromδ18O values of a stalagmite in Dongge,and a recorded shift in solar activity.The findings of this study illustrate that coupled analysis ofδ18O values of cellulose and carbonates from lake sediments may be used as a paleotemperature proxy.These results also provide further evidence of the existence of LIA in southwestern China. | ZHU ZhengJie CHEN JingAn ZENG Yan | 2014 | Science China Earth Sciences2014，57，6： | 4 |
| 4 | 湖泊沉积多指标记录的长寿湖近60年来营养化过程显示文摘长寿湖位于重庆市长寿区境内,是重庆市最大的湖泊旅游风景区和淡水鱼养殖基地之一。近年来,其营养化日趋严重。本文通过对有机质碳、氮含量、碳氮比值、有机质碳同位素等有机质指标的分析,结合^(137)Cs放射性核素定年,探讨了长寿湖近60年来有机质转化及营养演化过程。结果表明:长寿湖有机质主要来源于水生植物藻类,受陆源影响较小;湖泊环境演化分为两个截然不同的阶段:1980年以前,有机质碳、氮含量较低,C/N比值较小,有机质碳同位素值较大,暗示湖泊营养环境为贫营养化。1980年以后,有机质碳、氮含量较高,C/N比值较大,有机质碳同位素值偏负,说明湖泊已经处于营养化阶段,人为活动的增强及养殖业的发展是导致湖泊生产力增大的主要因素。长寿湖沉积物多指标忠实记录了湖泊环境的演化过程。 | 朱正杰 肖军 龚业超 杨洪永 张雄 双燕 毛玲玲 | 2016 | 地球环境学报2016，7，3： | 3 |
| 5 | 贵州草海近21ka以来有机地球化学记录反映的古环境变化显示文摘草海位于黔滇交界,主要受印度夏季风的影响,其湖沼沉积物记录了中-晚第四纪的环境变化历史,是研究第四纪环境和季风演变的良好载体。本研究选取的南屯NT03钻孔,岩心长405 cm,在放射性碳同位素(AMS14C)测年基础上建立了年代序列,并进行了沉积物的色差值(L*)、烧失量(LOI550)、总有机碳(TOC)、碳氮比(C/N)和有机稳定碳同位素(δ13Corg)等古环境替代指标的测试。实验结果显示,L*、LOI550和TOC等3个有机碳含量指标同步变化,共同指示该钻孔序列经历了3个沉积环境演变阶段,即末次盛冰期晚期(21-15 cal ka BP)河流-冲积相沉积阶段、冰消期至早中全新世(15-4 cal ka BP)高湖面湖泊-沼泽相沉积阶段和晚全新世(4 cal ka BP以来)洪冲积相沉积阶段。近2万年以来草海湖沼面积经历的收缩→扩张→收缩演变过程与石笋氧同位素变化基本吻合,表明季风降雨是引起草海湖泊水体和周边生态系统变化的主要因素。δ13Corg指标变化范围为-29. 28‰^-24. 19‰,表明草海盆地周围植被组成在末次盛冰期以来C4草本虽然略有增加,但均以C3植物为主。同时,TOC和δ13Corg指标证明了B/A冰消期暖事件对盆地边缘区的湿地泥炭富集起到关键作用,而多指标揭示了近4 ka以来水域变浅并发展成为冲积环境的过程,也可能与石笋记录的夏季风减弱所带来的降水量减少有关。 | 龚晓飞 陈聪 汤永杰 黄康有 乐远福 梁凯璇 郑卓 | 2019 | 古地理学报2019，21，6： | 1 |
| 6 | Environmental evolution recorded by multi-proxy evidence in Lake Chenghai sediments, Yunnan Province during recent 100 years显示文摘Lacustrine sediments can provide potential information about environmental changes in the past. On the basis of high-resolution multi-proxy analysis including carbon and nitrogen contents of organic matter, C/N ratios, inorganic carbon contents, and carbon and oxygen isotopic composition of carbonate, together with precise 137Cs dating, the environmental evolution of Lake Chenghai, Yunnan Province, during the past 100 years has been investigated. It is shown that the carbonate in Lake Chenghai is authigenic, and the organic matter is mainly derived from aquatic plants and algae, instead of terrestrial-source materials. The environmental evolution of Lake Chenghai can be diverged into three periods with the contrasting characteristics during the past 100 years. Before 1940, the stable carbon and oxygen isotope values, the poor correlation between them and the lower carbon and nitrogen contents of organic matter suggested that Lake Chenghai was open, and the lake water was oligotrophic during that period. During 1940-1993, the negative δ13C values and the gradual increase of carbon and nitrogen contents of organic matter and C/N ratios indicated that the eutrophication was aggravated. The closeness of Lake Chenghai and human activities may be responsible for this eutrophication. After 1993, notable increases in carbon and oxygen isotopic values of carbonate, carbon and nitrogen contents of organic matter, C/N ratios and inorganic carbon contents demonstrated that the increase of lacustrine productivity and the serious eutrophication were resulted from strong human activities. Therefore, the multi-proxy in Lake Chenghai sediments has reliably recorded the natural environmental evolution and the impacts from human activities. | ZHU Zhengjie CHEN Jing'an REN Shicong ZENG Yan | 2013 | Chinese Journal Of Geochemistry2013，32，1： | 0 |
| 7 | A review on bivalve shell, a tool for reconstruction of paleo-climate and paleo-environment显示文摘Environmental information can be extracted from bivalve shell geochemistry. In this review, the latest research progress and the existing problems as well as the focus of future research on stable oxygen and carbon isotopic composition and trace elemental ratios of bivalve shell were investigated. Oxygen isotopic signatures of bivalve shell have been proved precipitate in equilibrium with their host water and used as a robust tool to reconstruct ancient water temperature. In order to reconstruct quantitative paleo-temperature information, the future research on bivalve shell oxygen isotope should combine with the study of ancient water oxygen isotope. Metabolic effect prevents the direct application of stable carbon isotopic composition of bivalve shell from extracting dissolved inorganic carbon information. The contribution of metabolic carbon to bivalve shell is species specific. Stable carbon isotopic composition of dissolved inorganic carbon could be reconstructed if the metabolic contribution could be accounted for. Explore ways to remove contribution of metabolic effects to bivalve shell is the future focus of the research. There is no consensus on the effect of temperature on bivalve trace element ratios, which may be also species specific, each proxy should ideally be validated and calibrated for each species before being used to interpret past climate and environmental conditions. Future research needs to pay attention to the bivalve shell biomineralization process, which controlled bivalve shell trace element ratios. Cultivation experiment is an important way to obtain the relevant conclusions. | YAN Hui CHEN Jie XIAO Jun | 2014 | Chinese Journal Of Geochemistry2014，33，3： | 0 |
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