發(fā)布時(shí)間：2018-05-12 03:34

  本文選題：石筍 + 碳氧穩(wěn)定同位素�。� 參考：《西南大學(xué)》2015年碩士論文

【摘要】：全新世時(shí)期全球氣候變化,是國(guó)際全球氣候變化研究計(jì)劃的最為重要的內(nèi)容之一,重建全新世高分辨率的氣候記錄,對(duì)于認(rèn)識(shí)氣候系統(tǒng)變化規(guī)律、應(yīng)對(duì)當(dāng)前面臨的嚴(yán)峻氣候和環(huán)境形勢(shì)、預(yù)測(cè)未來(lái)氣候變化趨勢(shì)有著至關(guān)重要的意義。目前全新世氣候演變研究逐漸深入,取得了一些成果,為進(jìn)一步研究全新世氣候變化奠定了基礎(chǔ),但是全新世時(shí)期的氣候變化驅(qū)動(dòng)機(jī)制依然存在爭(zhēng)議。洞穴石筍與黃土、冰芯、樹(shù)輪、湖泊沉積、孢粉等氣候重建代用指標(biāo)相比,具有精確定年、分辨率高、保存氣候環(huán)境記錄完整、分布廣泛、樣品易得且成本低廉等顯著優(yōu)勢(shì),已經(jīng)成為當(dāng)前研究古氣候記錄的主力軍之一。本文以長(zhǎng)江上游地區(qū)重慶市青木關(guān)鎮(zhèn)為研究區(qū)域,利用青木關(guān)地區(qū)獅子山洞石筍QM09的25個(gè)230Th精確定年和315個(gè)碳氧同位素?cái)?shù)據(jù)重建了0～9.4kaBP期間的高分辨率石筍碳氧同位素的時(shí)間序列,結(jié)合亞洲季風(fēng)區(qū)的其他洞穴的石筍記錄,分析石筍氧同位素與全新世時(shí)期氣候的響應(yīng)關(guān)系,并討論了全新世內(nèi)部的氣候波動(dòng)變化趨勢(shì)；利用石筍碳同位素嘗試分析與當(dāng)時(shí)氣候變化、植被變化關(guān)系,進(jìn)而分析人類活動(dòng)與全新世氣候之間存在的響應(yīng)關(guān)系,全新世時(shí)期人與自然環(huán)境之間的關(guān)系,目前研究的重點(diǎn)主要側(cè)重于自然環(huán)境的變化對(duì)人類活動(dòng)產(chǎn)生的影響,尤其是“4.2ka事件”以來(lái),對(duì)人類活動(dòng)影響自然環(huán)境的研究較為缺乏,深入探討人類活動(dòng)的影響是本文的重點(diǎn)和創(chuàng)新點(diǎn),通過(guò)探討得出如下結(jié)論：(1)獅子山洞石筍QM09高分辨率氧同位素記錄顯示：獅子山洞所處的重慶地區(qū)氣候變化與亞洲季風(fēng)區(qū)其他地區(qū)氣候變化趨勢(shì)基本保持一致,石筍記錄具有可重復(fù)性,顯示獅子山洞石筍基本沒(méi)有受到區(qū)域因素的影響,研究區(qū)內(nèi)在6.0～9.4kaBP期間,8180值變化范圍為-9.483%～-11.187%o,平均值為-10.435‰,變化幅度達(dá)到1.704%o,氧同位素值整體處于偏負(fù)狀態(tài),表明此階段季風(fēng)整體處于強(qiáng)盛階段,降水豐富；在4.2～6.0kaBP期間,石筍δ18O值變化范圍為-8.874%o-10.762%o,平均值為-9.776‰,變化幅度為1.888%o,顯示石筍δ18O值開(kāi)始逐漸偏正,但整體還是處于偏負(fù)狀態(tài),表明此階段季風(fēng)整體保持強(qiáng)勢(shì)狀態(tài),降水充沛,內(nèi)部存在季風(fēng)波動(dòng),季風(fēng)加強(qiáng)和減弱事件交替出現(xiàn)；4.2ka BP以來(lái),石筍δ180值變化范圍為-7.132%～-9.921‰，平均值為-8.538‰,變化幅度為2.789‰,δ18O值顯示已經(jīng)開(kāi)始處于偏正狀態(tài),表明季風(fēng)整體開(kāi)始減弱,降水逐漸減少。(2)獅子山洞石筍QM09高分辨率碳同位素記錄顯示：獅子山洞石筍QM09的碳同位素在4.5-9.4ka BP期間,碳同位素值變化范圍為-14.555%o～-13.341%o,變化幅度為1.2140‰,平均值為-13.911‰,可以看出碳同位素值基本在-14%o上下波動(dòng),整體處于偏負(fù)狀態(tài),能夠指示重慶地區(qū)植被覆蓋率較高,植被類型以C3植被為主要植被類型,C4植被相對(duì)較少；4.2ka BP以來(lái),碳同位素值變化范圍為-14.403‰～-5.848‰,變化幅度為8.555‰,平均值為-11.260‰,碳同位素值出現(xiàn)強(qiáng)烈波動(dòng),整體趨于偏正狀態(tài),指示C3植被覆蓋率明顯下降,自然生態(tài)環(huán)境趨于惡化。(3)4.2ka BP以來(lái),尤其是近2000年來(lái),重慶地區(qū)人類活動(dòng)的規(guī)模明顯增多和范圍明顯擴(kuò)大,對(duì)自然植被的影響進(jìn)一步擴(kuò)大,改變了地表的植物類型,間接影響了土壤有機(jī)質(zhì)和生物量,土壤有機(jī)質(zhì)降低和生物量的減少,使石筍形成的中間環(huán)節(jié),尤其是石筍碳同位素產(chǎn)生變化,使其逐漸偏重,論證了人類活動(dòng)通過(guò)改造地表植被類型會(huì)對(duì)自然環(huán)境產(chǎn)生影響的結(jié)論。
[Abstract]:The global climate change during the Holocene is one of the most important contents of the international global climate change research program. The reconstruction of a Holocene high resolution climate record is of great significance for understanding the changing rules of the climate system, dealing with the severe climate and environmental situation and predicting the trend of climate change in the future. The study of the Holocene climate evolution has been progressively deepening, and some achievements have been obtained, which lay a foundation for further study of the Holocene climate change, but the driving mechanism of climate change in the Holocene is still controversial. The Cave Stalagmite is accurate and accurate in comparison with the climatic reconstruction indicators such as loess, ice core, tree wheel, lake deposition and sporopollen. It has become one of the main forces in the study of paleoclimate records. This paper takes the Chongqing city of Chongqing city in the upper reaches of the Yangtze River as the research area, and uses 25 230Th precise years and 315 carbon and oxygen in the green shoot of the lion cave in the Qinghai Province. The isotopic data reconstructs the time series of high resolution carbon and oxygen isotopes of stalagmite during the period of 0 to 9.4kaBP, combined with the stalagmite records of other caverns in the Asian monsoon region, and analyses the response relationship between the oxygen isotope of the stalagmite and the Holocene epoch, and discusses the trend of the climate change in the Holocene. The relationship between climate change and vegetation change at that time, and then the response relationship between human activity and Holocene climate, the relationship between human and natural environment during the Holocene, the focus of the present study mainly on the effects of natural environment changes on human activities, especially since the "4.2ka event". The research on the influence of the natural environment is relatively short. It is the key and innovation point of this paper. Through the discussion, the following conclusions are drawn: (1) the QM09 high resolution oxygen isotope records of the Stalagmite in the lion cave show that the climate change in the Chongqing region of the lion cave and the climate change trend in other regions of the Asian monsoon region Keeping the same, the stalagmite records are repeatable, showing that the Stalagmite in the lion cave is not affected by regional factors. During the period of 6 ~ 9.4kaBP, the range of 8180 values is -9.483% to -11.187%o, the average value is -10.435 per 1000, the change range is 1.704%o, the oxygen isotope value is in the negative state, indicating the monsoon in this stage. During the period of 4.2 ~ 6.0kaBP, the variation range of the delta 18O value of the stalagmite is -8.874%o-10.762%o, the average value is -9.776 per 1000, the change range is 1.888%o, which shows that the value of the stalagmite Delta 18O begins to be positive, but the whole is still in a negative state, which indicates that the monsoon in this stage remains strong, and the precipitation is abundant and internal exists. The monsoon fluctuation occurred alternately in the monsoon strengthening and weakening events; since 4.2ka BP, the variation range of the delta 180 value of the stalagmite was -7.132% to -9.921 per thousand, the average value was -8.538 per 1000, the change range was 2.789 per thousand, and the delta 18O value showed that the monsoon began to be in the positive state, indicating that the monsoon began to weaken and the precipitation decreased gradually. (2) the high resolution of the stalagmite QM09 in the lion cave. Carbon isotope records show that the carbon isotope of QM09 in the lion cave in 4.5-9.4ka BP, the variation range of carbon isotope value is -14.555%o to -13.341%o, the variation range is 1.2140 per thousand and the average value is -13.911 per 1000. It can be seen that the carbon isotope value fluctuates basically in the upper and lower -14%o, and the whole body is in the negative state, which can indicate the vegetation cover in Chongqing area. The cover rate is higher, the vegetation type is C3 vegetation as the main vegetation type, and the C4 vegetation is relatively less. Since 4.2ka BP, the variation range of carbon isotope value is from -14.403 to -5.848 per thousand, the variation range is 8.555 per thousand, the average value is -11.260 per thousand, the carbon isotope value fluctuates strongly, the whole trend is in the partial positive state, indicating that the vegetation coverage rate of C3 is obviously decreased, naturally the vegetation coverage of C3 is decreased obviously. Nature The ecological environment tends to deteriorate. (3) since 4.2ka BP, especially in recent 2000, the scale of human activities in Chongqing area has increased obviously and its scope is obviously expanded, the influence of the natural vegetation is further expanded, the plant type of the surface is changed, the soil organic matter and the biomass, the decrease of soil organic matter and the decrease of the biomass, make the stalagmite The intermediate links formed, especially the carbon isotopes of stalagmite, make it more and more heavy, demonstrating the conclusion that human activities will affect the natural environment through the transformation of the vegetation types of the surface.

【學(xué)位授予單位】：西南大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：P532

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 王心源;吳立;張廣勝;王官勇;韓偉光;;安徽巢湖全新世湖泊沉積物磁化率與粒度組合的變化特征及其環(huán)境意義[J];地理科學(xué);2008年04期

2 史威;朱誠(chéng);徐偉峰;關(guān)勇;孫智彬;;重慶中壩遺址剖面磁化率異常與人類活動(dòng)的關(guān)系[J];地理學(xué)報(bào);2007年03期

3 張美良,程海,林玉石,覃嘉銘,張會(huì)領(lǐng),涂琳玲,王華,馮玉梅;貴州荔波1.5萬(wàn)年以來(lái)石筍高分辨率古氣候環(huán)境記錄[J];地球化學(xué);2004年01期

4 遲寶泉;周厚云;趙建新;韋剛健;關(guān)華政;俸月星;朱照宇;周國(guó)慶;閆峻;;54～46ka川東北石筍的氧同位素記錄及其氣候環(huán)境意義探討[J];地球化學(xué);2007年04期

5 覃嘉銘,袁道先,林玉石,張美良,李彬;桂林44kaB.P.石筍同位素記錄及其環(huán)境解譯[J];地球?qū)W報(bào);2000年04期

6 劉東生,譚明,秦小光,趙樹(shù)森,李鐵英,呂金波,張德二;洞穴碳酸鈣微層理在中國(guó)的首次發(fā)現(xiàn)及其對(duì)全球變化研究的意義[J];第四紀(jì)研究;1997年01期

7 覃嘉銘,林玉石,張美良,李紅春;桂林全新世石筍高分辨率δ~(13)C記錄及其古生態(tài)意義[J];第四紀(jì)研究;2000年04期

8 吳文祥,劉東生;4000aB.P.前后東亞季風(fēng)變遷與中原周圍地區(qū)新石器文化的衰落[J];第四紀(jì)研究;2004年03期

9 劉東生;開(kāi)展“人類世”環(huán)境研究,做新時(shí)代地學(xué)的開(kāi)拓者——紀(jì)念黃汲清先生的地學(xué)創(chuàng)新精神[J];第四紀(jì)研究;2004年04期

10 程海,艾思本,王先鋒,汪永進(jìn),孔興功,袁道先,張美良,林玉石,覃嘉銘,冉景丞;中國(guó)南方石筍氧同位素記錄的重要意義[J];第四紀(jì)研究;2005年02期

相關(guān)博士學(xué)位論文 前2條

1 劉啟明;貴州涼風(fēng)洞石筍的古氣候記錄與古生態(tài)環(huán)境意義[D];中國(guó)科學(xué)院研究生院（地球化學(xué)研究所）;2003年

2 楊勛林;青藏高原東部近1200年來(lái)高分辨率洞穴石筍δ～（18）O記錄[D];蘭州大學(xué);2007年

相關(guān)碩士學(xué)位論文 前6條

1 況潤(rùn)元;湖北神農(nóng)架近2000年來(lái)的石筍氣候記錄[D];南京師范大學(xué);2003年

2 陳昌海;長(zhǎng)江下游石筍記錄的中全新世東亞季風(fēng)降水高頻變率[D];南京師范大學(xué);2005年

3 董進(jìn)國(guó);全新世高低緯氣候耦合過(guò)程的神農(nóng)架洞穴記錄[D];南京師范大學(xué);2007年

4 張?jiān)旅?高分辨率石筍記錄的三峽庫(kù)區(qū)過(guò)去500年氣候變化研究[D];西南大學(xué);2013年

5 梁軒;青木關(guān)巖溶流域土壤水水化學(xué)變化特征及其控制因素[D];西南大學(xué);2013年

6 黃帆;高分辨率石筍記錄的重慶地區(qū)60～90 ka BP時(shí)段氣候變化研究[D];西南大學(xué);2014年

，

本文編號(hào)：1876958