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    题名 作者 年代 出处 被引量
1青藏高原东缘晚新生代成都盆地物源分析与水系演化显示文摘成都盆地位于青藏高原东缘,夹于龙门山与龙泉山之间,盆地中充填了3.6M a以来的大邑砾岩、雅安砾石层和晚更新世—全新世砾石层,其物源均来源于盆地西侧的龙门山,具横向水系和单向充填的特征。本次以物源区分析作为切入点,以岷江和青衣江水系为重点,采用砾岩成分分析、砂岩岩屑成分分析、重矿物分析和砾石的地球化学分析等基本方法,开展青藏高原东缘晚新生代以来的古水系重建工作,研究结果表明,成都盆地主要有两个物源区,其中成都盆地北部的都江堰街子场、崇州白塔山、大邑白岩沟、大邑氮肥厂、彭州丁家湾、彭州葛仙山等剖面中的砾石层在碎屑成分、重矿物和花岗岩砾石的地球化学成分等方面相似,应为古岷江的产物,而其与现代岷江在砾岩成分和重矿物特征等方面的差异性则表明古岷江可能存在改道的现象;成都盆地南部的庙坡剖面和熊坡东剖面中的砾石层在碎屑成分、重矿物和花岗岩砾石的地球化学成分等方面相似,应为古青衣江的产物,但其流向却与现代青衣江的流向不同,表明熊坡背斜是在大邑砾岩沉积之后隆起的,它的隆起迫使古青衣江改道。李勇 黎兵 Steffen D DensmoreAL RichardsonNJ 周荣军 Ellis M A 张毅 2006沉积学报2006,24,3:38
2博斯腾湖碳酸盐和同位素组成的全新世古环境演变高分辨记录及与冰川活动的响应显示文摘本文通过对在新疆南部塔里木盆地北缘博斯腾湖采集的一根953cm的岩心进行了早全新世以来的古气候重建。对BSTC2000岩心进行了碳酸盐矿物组成、Ca/1000Sr,有机质TOC,C/N和C/S分析,并结合BSTC2000岩心附近的一个沉积物剖面的孢粉资料,利用多指标重建了8500aBP以来的古气候变化特征。在2个平行岩心中对保存的植物叶片、草籽,以及全有机质进行了9个AMS14C年代测定。8500~8100aBP气候冷湿,钻孔位置为河流-滨湖相环境,沉积物中有3层泥炭层。从8100~6400aBP,气温升高,湖泊扩张,气候暖湿,湖泊可能为最高湖面时期。而从6400~5100aBP湖泊稍微下降,气候变冷。在中全新世晚期从5100~3100aBP气候变得高温干旱,但其间的4400~3800aBP有短暂的气候变冷,早期大量的冰雪融水补给博斯腾湖,使得湖泊水位上升。湖泊的第二个高湖面期是5200~3800aBP。在3100~2200aBP气候冷湿,由于蒸发减弱而湖泊有所扩张,湖泊在3100至2800aBP期间是最后一次短暂的高湖面期。这次短期高湖面后,湖泊由于较长时期的低温而引起的供水减少,湖泊收缩。从2200~1200aBP,气候变得干热,湖泊收缩。尽管从1200aBP以来,温度有所下降,气候变得暖干,湖泊又开始有所上升,但是没有达到博斯腾湖出水口孔雀河的海拔高度。张成君 郑绵平 A PROKOPENKO M STEFFEN 匡娟 杨奇丽 郭方琴 冯兆东 2007地质学报2007,81,12:25
3National Forest Inventories capture the multifunctionality of managed forests in Germany显示文摘Background:Forests perform various important ecosystem functions that contribute to ecosystem services.In many parts of the world,forest management has shifted from a focus on timber production to multi-purpose forestry,combining timber production with the supply of other forest ecosystem services.However,it is unclear which forest types provide which ecosystem services and to what extent forests primarily managed for timber already supply multiple ecosystem services.Based on a comprehensive dataset collected across 150 forest plots in three regions differing in management intensity and species composition,we develop models to predict the potential supply of 13 ecosystem services.We use those models to assess the level of multifunctionality of managed forests at the national level using national forest inventory data.Results:Looking at the potential supply of ecosystem services,we found trade-offs(e.g.between both bark beetle control or dung decomposition and both productivity or soil carbon stocks)as well as synergies(e.g.for temperature regulation,carbon storage and culturally interesting plants)across the 53 most dominant forest types in Germany.No single forest type provided all ecosystem services equally.Some ecosystem services showed comparable levels across forest types(e.g.decomposition or richness of saprotrophs),while others varied strongly,depending on forest structural attributes(e.g.phosphorous availability or cover of edible plants)or tree species composition(e.g.potential nitrification activity).Variability in potential supply of ecosystem services was only to a lesser extent driven by environmental conditions.However,the geographic variation in ecosystem function supply across Germany was closely linked with the distribution of main tree species.Conclusions:Our results show that forest multifunctionality is limited to subsets of ecosystem services.The importance of tree species composition highlights that a lack of multifunctionality at the stand level can be compensated by managing forests at the landscape level,when stands of complementary forest types are combined.These results imply that multi-purpose forestry should be based on a variety of forest types requiring coordinated planning across larger spatial scales.Nadja K.Simons María R.Felipe-Lucia Peter Schall Christian Ammer Jürgen Bauhus Nico Blüthgen Steffen Boch François Buscot Markus Fischer Kezia Goldmann Martin M.Gossner Falk Hänsel Kirsten Jung Peter Manning Thomas Nauss Yvonne Oelmann Rodica Pena Andrea Polle Swen C.Renner Michael Schloter Ingo Schöning Ernst-Detlef Schulze Emily F.Solly Elisabeth Sorkau Barbara Stempfhuber Tesfaye Wubet Jörg Müller Sebastian Seibold Wolfgang W.Weisser 2021Forest Ecosystems2021,8,1:2
4Differential in vivo and in vitro expression of vascular endothelial growth factor (VEGF)-C and VEGF-D in tumors and its relationship to lymphatic metastasis in immunocompetent rats显示文摘 Kirkin V Steffen A 2003Cancer Res2003,63,3:1
5Light and excess manganese implications for oxidative stress in common bean显示文摘Gonzalez A Steffen KL Lyncb JP 1998Plant Physiology1998,,8:1
6Nighttime blood pressure dipping:the role of the sympathetic nervous system显示文摘Sherwood A Steffen PR Blumenthal JA 0,,2:1
7查看详情显示文摘Baur M Fedorov A Steffen L Filipp S Silva M P Wallraff A 0,,:1
8Cages:designs and coneepts显示文摘Steffen T Tsantrizos A Fruth I 2000J Eur Spine J2000,9,:1
9Differential in vivo and in vitro expression of vascular endothelial growth factor VEGF-C and VEG F-D in tumor and its relationship to lymphatic metastaisis in immunocompetent rats显示文摘Krishnan J KirKin V Steffen A 2003Cancer Res2003,63,3:1
10Differential in vivo and in vitro expression of vascular endothelial growth factor (VEGF)-C and VEGF-D in tumors and its relationship to lymphatic metastasis in immunocompetent rats显示文摘 Kirkin V Steffen A 2003Cancer Res2003,63,3:1
11In vivo engineering of a human vasculature for bone tissue engineering applications显示文摘Steffens L Wenger A Stark GB 2009J Cell Mol Med2009,13,9:1
12Mineralisation of supper (14)C- labblled synthetic lignin and linginoltic enzyme activities of litter decomposing basi-diomycetous fungi 显示文摘Steffen K T Hofrichter M Hatakka A 2000Applied Microbiology and Biotechnology2000,54,6:1
13A comparison of ear reattachment methods: a review of 25 years since pennington 显示文摘Steffen A Katzbach R Klaiber S 2006Plast Reconstr Surg2006,118,6:1
14Analysis of flavor volatiles usingheadspaee solid-phase mieroextraetion 显示文摘Pawliszyn Steffen A 1996Journal of Agriculture and Food Chemistry1996,,44:1
15Gender and leadership style:A meta-analytic review of the social psychological literature显示文摘Eagly A H Steffen V J 0,,:1
16A W-band MMIC radar system for remote detection of vital signs 显示文摘Sebastian D Serdal A Steffen S 2012Journal of In- flared Millimeter and Terahertz Waves2012,33,12:1
17A strong coupling partitioned approach for fluid-structure interaction with free surfaces显示文摘WOLFGANG A W STEFFEN G EKKEHARD R 0,,:1
18Theory of regular M-band wavelet bases显示文摘Steffen P Heller P N Gopinath R A 1993IEEE Trans Signal Proccessing1993,,41:1
19Actin polymerization machinery: the finish line of signaling networks, the starting point of cel- lular movement显示文摘Disanza A Steffen A Hertzog M 2005Cellu Mol Life Sci2005,62,9:1
20Church G Automated modelling of signal transduction networks显示文摘Steffen M Petti A Aach J 2002BMC Bioinformatics2002,3,1:1
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