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  本文選題：深層土壤　切入點：有機碳儲量　出處：《中國科學院研究生院（教育部水土保持與生態(tài)環(huán)境研究中心）》2015年碩士論文　論文類型：學位論文

【摘要】：土地利用變化在全球碳平衡及氣候變化中起著重要作用。目前對黃土高原地區(qū)土壤有機碳庫雖然已經(jīng)進行了大量卓有成效的研究工作,但絕大部分仍是以淺層有機碳含量或者有機碳庫大小作為研究對象,而近期一些研究表明,1m以下的深層土壤積聚的有機碳十分可觀。該區(qū)天然次生林轉(zhuǎn)變?yōu)槿斯ち旨稗r(nóng)田等植被破壞過程中,土壤有機碳變化的研究還鮮見報道,還不足以科學認識該區(qū)土地利用變化對土壤有機碳的影響方式和程度。本文以黃土丘陵區(qū)子午嶺為研究區(qū),以天然喬木林、天然灌木林、人工喬木林、撂荒地、農(nóng)地5種不同土地利用類型為研究對象,以淺層(0~100cm)土壤為對照,研究深層土壤有機碳儲量和有機碳組分對土地利用變化響應(yīng)的程度、方式、機理,以及土地利用變化后年限與土壤有機碳的關(guān)系。并且對土壤溶解性有機碳遷移特征及其動態(tài)變化進行了研究,進一步了解深層有機碳來源問題。研究取得以下主要結(jié)果:1.黃土丘陵子午嶺林區(qū)天然喬木林、天然灌木林、人工喬木林、撂荒地、農(nóng)地0~200cm有機碳儲量分別為134.65t?hm-2、96.23t?hm-2、124.98t?hm-2、76.03t?hm-2、82.75t?hm-2,深層(100~200cm)土壤有機碳儲量分別占0~200cm總有機碳儲量的33%、29%、31%、34%、42%。2.不同土地利用類型間0~200cm土壤有機碳含量有一定差異,以天然喬木林和人工林地最高,其次是天然灌木林地,撂荒地和農(nóng)田土壤有機碳含量最低。不同利用類型間淺層土壤有機碳含量差異顯著,但深層土壤有機碳含量差異不大。3.土地利用變化對土壤有機碳儲量影響顯著,淺層比深層變化更敏感。天然喬木林轉(zhuǎn)變?yōu)槿斯�喬木林、天然喬木林轉(zhuǎn)變?yōu)檗r(nóng)田、天然灌木林轉(zhuǎn)變?yōu)榱袒牡丶稗r(nóng)田四種土地利用轉(zhuǎn)變方式導致淺層土壤有機碳儲量減少幅度為2%~48%,深層減少幅度為12%~22%。4.天然灌木林地轉(zhuǎn)變?yōu)檗r(nóng)田土壤有機碳儲量隨著開墾時間的增長而降低,開墾0~30年,有機碳含量儲量下降較快,降幅為31%。淺層(0~100cm)土壤有機碳儲量在開墾30~50年有略微下降,降幅為8%,50年后基本不變。而深層(100~200cm)土壤有機碳儲量變化幅度較小,介于4%~15%之間。5.不同土地利用類型土壤深層(60~200cm)活性有機碳占0~200cm活性有機碳含量的8%~51%。不同土地利用轉(zhuǎn)變方式不僅對淺層(0~60cm)土壤活性有機碳有影響,對深層(60~200cm)也有一定影響。天然喬木林轉(zhuǎn)變?yōu)槿斯�喬木林、天然喬木林轉(zhuǎn)變?yōu)檗r(nóng)田、天然灌木林轉(zhuǎn)變?yōu)榱袒牡丶稗r(nóng)田四種土地利用轉(zhuǎn)變方式深層土壤易氧化性碳減少幅度為1%~21%;土壤微生物量碳減少幅度為8%~25%。6.土壤溶解性有機碳含量隨土壤剖面深度的增加而逐漸降低,與有機碳含量顯著相關(guān);淺層(0~100cm)和深層(100~200cm)溶解性有機碳含量分別占0~200cm土層總含量58%和42%。灌木林地DOC淋溶10d后土壤0~200cm整個土層DOC增加量增幅為23%;入滲30d的淺層(0~100cm)和深層(100~200cm)DOC分別僅增加5%和4%。
[Abstract]:Land use change plays an important role in global carbon balance and climate change. But most of them still study the content of shallow organic carbon or the size of organic carbon pool. Some recent studies have shown that the accumulation of organic carbon in the deep soil below 1 m is considerable. In the process of the natural secondary forest being transformed into artificial forest and farmland, there are few reports on the change of soil organic carbon. This paper takes Ziwuling of loess hilly area as the research area, takes natural tree forest, natural shrub forest, artificial arbor forest, abandoned land, etc. Five different land use types of farmland were studied, and the degree, mode and mechanism of deep soil organic carbon storage and organic carbon components response to land use change were studied. The relationship between soil organic carbon (SOC) and land use change (LUCF), and the characteristics and dynamic changes of soil dissolved organic carbon (SOC) transport were also studied. The main results of the study are as follows: 1. Natural Arbor Forest, Natural shrub Forest, artificial Arbor Forest, abandoned Land, and Agricultural Land (0 ~ 200cm) in the Loess Hilly Ziwuling Forest region are respectively 134.65 t ~ (-1)? Hm-2n 96.23t? Hm-2n 124.98t? Hm-2? 76.03t? Hm-2n 82.75t? The soil organic carbon reserves of 0 ~ 200cm were 3329 ~ 31C ~ (34) ~ (42cm) respectively. There were some differences in soil organic carbon contents between different land use types, among which the natural tree forest and artificial forest land were the highest, followed by natural shrub forest land, the soil organic carbon reserves of 0 ~ (200 ~ 2) cm were higher than that of the natural forest land, and the soil organic carbon storage was 100 ~ (100 ~ (200) cm) of the total organic carbon storage of 0 ~ (200 cm), respectively. The soil organic carbon content of abandoned land and farmland was the lowest. The content of organic carbon in shallow soil was significantly different among different utilization types, but there was no significant difference in organic carbon content in deep soil. 3. Land use change had a significant effect on soil organic carbon storage. The shallow layer is more sensitive than the deep layer change. The natural tree forest turns into the artificial tree forest, the natural tree forest turns into the farmland, The conversion of natural shrub forest to abandoned land and farmland has resulted in the decrease of soil organic carbon reserves in shallow layer by 248%, and in deep layer by 120.22.4. the natural shrub land is transformed into farmland soil organic carbon storage with the opening of soil organic carbon storage. With the increase of reclamation time, During the period of 0 ~ 30 years of reclamation, the content of organic carbon decreased rapidly, the decrease was 31%.) the soil organic carbon reserve decreased slightly from 30 to 50 years, the decrease was 8%, and after 50 years it was basically unchanged.) the change of soil organic carbon storage in the deep layer (100 ~ 100 cm) was relatively small. The content of active organic carbon in 0 ~ 200 cm soil is 80.51% of the total active organic carbon content of 0 ~ 200cm. Different land use transformation patterns not only affect the soil active organic carbon content in shallow layer (0 ~ (60) cm), but also have a significant effect on the soil organic carbon content of 0 ~ 200 cm in different land use types. Natural Arbor Forest is transformed into artificial Arbor Forest and Natural Arbor Forest turns into farmland. Conversion of natural shrub forest to abandoned land and farmland four types of land use transformation methods the extent of reduction of oxidizing carbon in deep soil is 1 / 21, and that of microbial biomass carbon in soil is 8 / 25.6.The content of dissolved organic carbon in soil varies with the depth of soil profile. Increasing and gradually decreasing, There was a significant correlation between organic carbon content and organic carbon content. The content of dissolved organic carbon (DOC) in the soil layer of 0 ~ 200cm was 58% and 42cm, respectively. After 10 days of DOC leaching in shrub land, the increase of DOC in the whole soil layer of 0 ~ 200cm was 23%, while that in the shallow layer of 30d infiltration was 5% and 47.The content of DOC in deep layer (100200cm) increased only 5% and 4cm, respectively.
【學位授予單位】：中國科學院研究生院（教育部水土保持與生態(tài)環(huán)境研究中心）
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：S153.6;F301.2

【引證文獻】

相關(guān)會議論文 前1條

1 陳安冉;王祖?zhèn)?;土壤中水溶性有機碳研究進展[A];2012中國環(huán)境科學學會學術(shù)年會論文集（第三卷）[C];2012年

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本文編號：1577639