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1.
新疆北部黄土矿物成分特征分析 总被引：2，自引：1，他引：1
新疆北部黄土主要分布于天山北麓、准噶尔界山西麓、伊犁盆地、塔城盆地及博尔塔拉谷地。天山北麓黄土,形成南北宽约50公里。大致呈北西西一南东东方向延伸黄土带。黄土带高程在950—2400米之间,主要出露在河谷高阶地、低山和丘陵区,并复盖在不同时代的老地层之上。黄土厚度一般变化在数米至30米之间,最厚可达50米。如沙湾县鹿角湾黄土系由五层黄土(自上而下记为L_0、L_1、L_2、L_3、L_4)和四层古土壤(自上而下记为S_0、S_1、S_2、S_3)组成,其中S_0为埋藏黑垆土型古土壤,~(14)C年龄为2874±70年。S_1S_2和S_3属褐土型古土壤。L_2黄土底部的热释光龄为77,000±600年。据此,可分别与黄河中游不同时代黄土对比:L_0S_0相当于全新世黄土,L_2相当马兰黄土, 相似文献
2.
热解温度和时间对秸秆生物质炭特性的影响 总被引：3，自引：0，他引：3
为探究不同热解温度和时间对生物质炭理化性质的影响。以新疆主要作物棉花、小麦和苜蓿的秸秆为材料,在不同热解温度(400、500、600℃)、热解时间(0.5、1.0、2.0、4.0、6.0h)下制备生物质炭。测定生物质炭pH值、有机碳含量、阳离子交换量(CEC),并利用傅里叶红外光谱(FTIR)和扫描电镜(SEM)对生物质炭表面形貌和有机官能团进行分析表征。结果表明:三种生物质炭均为碱性。其表面孔隙发达,官能团种类丰富,均存在烷基、芳香基和一些含氧基团。随着热解温度升高,三种生物质炭的产率、有机碳含量和CEC都逐渐降低,pH值则逐渐升高。热解温度对生物质炭性质有显著性影响,而热解时间对生物质炭特性影响规律不明显。低温(400℃)生产的生物质炭更适用于农田土壤改良,改善土壤结构、提高土壤肥力;高温(600℃)生产的生物质炭更适用于有机、无机污染环境的修复,进而改善土壤或水体环境。 相似文献
3.
中亚哈萨克斯坦西部过去～30000年以来有机碳同位素变化及其意义 总被引：1，自引：0，他引：1
选取位于中亚干旱区哈萨克斯坦中西部的VA剖面作为研究对象,在AMS14C测年基础上,分析了该剖面记录的过去～30000年以来的有机碳同位素组成变化。结果表明:该剖面记录的过去～30000年以来有机质碳同位素值(δ13Corg)变化于-26.19‰--22.12‰之间,均值为-23.77‰,植被主要为C3植物,C4植物仅仅在末次冰盛期出现且其相对丰度极低。因此VA剖面土壤有机碳同位素组成变化主要反映的是C3植物对气候环境因子的响应,进一步对影响该地区植物碳同位素因素的分析发现,降水是控制该地区C3植物碳同位素变化的主要因素,即:降水增多导致C3植物碳同位素值偏负,可以用来指示研究区古降水变化趋势,CO2浓度以及温度仅仅在末次冰盛期对C3和C4植物相对丰度有一定的影响。 相似文献
4.
一万年以来西安鱼包头黄土剖面磁化率的古气候环境再讨论 总被引：1，自引：0，他引：1
对西安地区全新世以来的环境演变特征进行研究,从而为预测西安地区乃至中国和全球未来环境的发展趋势提供依据。通过对西安神禾塬鱼包头村典型剖面全新世黄土-古土壤地层的岩性描述、地层划分和对比,结合泾阳县新庄村AMS14C的年代测定和其他学者的测年数据,建立了该地区全新世以来黄土沉积年代序列。根据磁化率气候替代指标显示的曲线特征,阐述了这一替代指标在剖面上的变化规律,探讨了该黄土剖面所反映的东亚冬、夏季风强弱变化特点,论证和详细分析了西安地区全新世以来环境变化的特征和规律,进而对该剖面磁化率曲线特征与其他学者的孢粉谱建立的温度曲线对比。对西安地区全新世以来古气候的阶段性进行了详细分析和论证。将西安地区10000年以来的气候演变划分为7个气候阶段。 相似文献
5.
为预测西安地区乃至中国和全球未来环境的发展趋势提供依据,通过对西安地区泾阳南塬寨头村典型剖面全新世黄土—古土壤地层的岩性描述、地层划分和对比,结合泾阳县新庄村AMS14C的年代测定和其他学者的测年数据,建立了该地区全新世以来黄土沉积年代序列。根据磁化率气候替代指标显示的曲线特征,阐述了这一替代指标在剖面上的变化规律,探讨了该黄土剖面所反映的东亚冬、夏季风强弱变化特点,论证和详细分析了西安地区全新世以来环境变化的特征和规律,进而对该剖面磁化率曲线特征与其他学者的孢粉谱建立的温度曲线对比,对西安地区全新世以来古气候的阶段性进行了详细分析和论证。将西安地区10000年以来的气候演变划分为7个气候阶段。 相似文献
6.
7.
梁学战 《干旱区资源与环境》2016,(2):153-157
对第四纪泥石流活动周期及其与环境演变关系的研究,可以从宏观上预测现代泥石流发育规律及趋势。选取白龙江流域各阶地典型泥石流沉积剖面,用沉积层测年数据确定泥石流活动期发生年代,对比分析与其它古环境记录(新构造运动史、黄土-古土壤系列、深海δ~(18)O曲线)的关系。研究表明:白龙江流域泥石流活动划分为8个周期,即1.5Ma、0.73Ma、0.565~0.425Ma、0.245~0.165Ma、116.8±9.9Ka、50~25Ka、5~4Ka及3Ka以来。泥石流沉积活动周期与新构造运动活跃期有时间上的共轭性,与深海氧同位素δ~(18)O的奇数段及洛川黄土-古土壤系列中古土壤系列有很好的对应关系,泥石流活动是构造运动与气候变化耦合作用的结果。 相似文献
8.
青藏高原全新世风沙活动历史与环境变化 总被引：1，自引：0，他引：1
风沙活动记录的研究对于人们了解气候环境变迁有着重要意义。风成砂层的稳定出露可以作为风沙活动及沙漠形成的最直接证据,因而通过对风成砂-黄土-古土壤序列地层剖面进行对比分析,即可还原地质历史时期风沙活动历史与环境演化。通过对比青藏高原南部、柴达木盆地、共和盆地、青海湖盆地等地区风成沉积剖面的岩性变化,结合14C测年、热释光和光释光测年结果,建立了青藏高原地区全新世以来风沙活动演化历史。青藏高原全新世在11.0kaBP左右开始进入全新世,环境逐渐转向暖湿;9.0kaBP左右出现了一次强烈的风沙活动事件;7.7～4.6ka BP14C大部分地区为暖湿环境,而藏南地区有较大范围风成砂沉积,风沙活动强烈。全新世晚期区域性差异较大,但整体环境恶化,风沙活动增强。 相似文献
9.
天山北麓黄土剖面的光释光测年分析 总被引：1，自引：0，他引：1
利用单片再生剂量法(SAR),测量了天山北麓大佛寺(DFS)、牛圈子(NJZ)2个风成黄土剖面的OSL信号特征与年龄.结果表明:天山北麓黄土的初始OSL信号强度低于黄土高原地区,并且4～11 μm混合矿物颗粒的IRSL、post-IR信号及40 ～ 63 μm石英颗粒的BLSL信号对人工剂量响应的灵敏度较低,其中细颗粒混合矿物的post-IR信号,甚至难以拟合出满意的生长曲线和等效剂量.依据40～63 μm石英颗粒BLSL信号计算出的年龄与地层深度则对应良好.DFS剖面底部年龄为(6.85 ±0.56)ka,表明其黄土物质沉积始于全新世大暖期.NJZ剖面出露黄土的最老年龄为(23.83±2.36)ka,整个剖面包括了晚更新世马兰黄土上部及全新世早期黄土,而全新世大暖期以来的黄土物质则可能因流水侵蚀而缺失.通过计算可以确定DFS、NJZ 2个剖面的平均黄土沉积速率介于0.25～0.26m·ka-1. 相似文献
10.
探讨油页岩有机碳矿化分解过程、有机碳组分变化特征以及环境因素作用规律可为评价油页岩在栽培基质中应用的可行性提供科学依据.试验在室内控制温度和水分条件下,分析了洗盐和未洗盐油页岩有机碳矿化动态变化特征.结果表明:油页岩基质在60 d培养期间,温度升高10℃使未洗盐基质总矿化量分别增加2%～28%(100%田间持水量)、2%～22%(80%田间持水量)和1%～15%(60%田间持水量);洗盐基质则分别增加2%～17%(100%田间持水量)、1%～5%(80%田间持水量)和7%～14%(60%田间持水量).将第60 d基质中活性有机碳含量进行回归分析,发现两种不同供试油页岩活性有机碳含量与温度和水分之间均呈正相关关系;未洗盐油页岩活性有机碳含量与温度和水分间相关性不显著,而洗盐后油页岩活性有机碳含量与温度和水分之间相关性显著(P=0.0214).用一级动力学方程拟合油页岩基质有机碳矿化动态得到未洗盐基质分解速率常数最大达1.2×10-3/d,洗盐基质其分解速率常数介于0.5×10-3～0.7×10-3/d.油页岩在长达60 d的培养过程中表现为有机碳持续分解、活性有机碳递增,证实其在基质栽培中的应用将对养分持续供给和维护作物根系生理活性发挥重要作用. 相似文献
11.
The intensified monsoon increases summer rainfall and creates wet conditions in the Asian summer monsoon region during the early Holocene. Along with millennial-scale changes of the monsoon intensity, it is still unclear whether the boundary of the monsoon region changes according to monsoon variability. Investigations into the early Holocene environment in monsoon marginal zones are crucial for understanding the monsoon boundary changes. Zhuye Lake is located at the northwest edge of the Asian summer monsoon, the northern Qilian Mountains, which are less affected by modern summer monsoon water vapor. Previous studies have reached different conclusions regarding the early Holocene climatic and environmental changes based on different dating methods(14C and OSL(optically stimulated luminescence)) and materials(shells, carbonate, pollen concentrates and bulk organic carbon). In this study, we synthesized 102 14C dates and 35 OSL dates from ten Holocene sedimentary sections and ten paleo-shorelines in the lake basin. A comparison between ages from different dating methods and materials generally shows that carbon reservoir effects are relatively slight in Zhuye Lake while the disordered chronologies are mainly related to the erosion processes and reworking effects. In addition, proxy data, including lithology, pollen, total organic carbon and carbonate, were collected from different sites of Zhuye Lake. According to the new synthesis, the early Holocene environment was relatively humid, associated with high runoff and lake water levels. The result indicates that the monsoon boundary moves to the north during the period of the intensified monsoon. A typical arid-area lake was formed during the mid-Holocene when carbonate accumulation and high organic matter contents were the main features of this period. The lake retreated strongly during the late Holocene, showing a drought trend. Overall, the lake evolution is generally consistent with the Holocene Asian summer monsoon change, showing the monsoon influence to monsoon marginal zones. 相似文献
12.
退耕年限与方式对土壤团聚体稳定性及有机碳分布的影响 总被引：3，自引：0，他引：3
以黄土高原南部退耕还林年限6 a(FL06)和15 a(FL15)刺槐林地、退耕还草年限6 a(GL06)和15 a(GL15)紫花苜蓿草地为研究对象,以临近长期耕作坡耕地(CK)作为对照,采用湿筛法,分离出2 mm、1~2 mm、0.5~1 mm、0.25~0.5 mm和0.25 mm 5个粒级的水稳性团聚体,研究了退耕年限与方式对团聚体稳定性和不同粒径团聚体有机碳分布的影响。结果表明:在0~20 cm土层,退耕还林还草与未退耕相比能显著提高2 mm和1~2 mm粒径团聚体含量,显著减少0.25 mm粒径团聚体含量,其中对于2 mm和1~2 mm粒径团聚体在不同退耕年限与方式下含量表现为GL15GL06FL06FL15CK和GL15FL06GL06FL15CK;退耕还林和还草增加了两个土层的团聚体稳定性,GL15的平均重量直径(MWD)值和几何平均直径(GMD)值均最大,土壤结构最稳定,其次为GL06;不同退耕年限,2 mm粒径下退耕还林地和还草地、1~2 mm粒径下退耕还草地团聚体有机碳含量均随退耕年限的延长而增加。20~40 cm土层中,团聚体含量均值随粒径的减小而增加;MWD和GMD值均小于0~20 cm层;各粒径范围内退耕还林与还草后的团聚体有机碳含量与坡耕地相比总体表现出减小的趋势。研究结果表明,退耕改善了土壤结构,对各粒径团聚体有机碳含量分布的影响随退耕年限与方式不同效应各异,且GL15相较于其它退耕年限和方式下的样地有更好的土壤团聚体稳定性和更多的团聚体有机碳积累。 相似文献
13.
Soils which have been pretreated with carbofuran can degrade the insecticide more rapidly than untreated soils, with a consequent loss of efficacy. In laboratory studies, soils pretreated with carbofuran were found to degrade the chemical more rapidly than soils which were not so pretreated. When pretreated soils were sterilised, the rate of carbofuran degradation was much reduced, indicating that most of it was due to microbial action. Incubation of pretreated soil with [phenyl-U-14C]carbofuran led to the rapid disappearance of the parent compound (3 % left after seven days). Most of the 14C was accounted for as bound residue after seven days, whilst smaller amounts were recovered as carbon dioxide, 3-hydroxycarbofuran, 3-ketocarbofuran, and an unknown metabolite. Incubation of pretreated soil with [carbonyl-14C]carbofuran led to rapid loss of the parent compound and the recovery of 73% of 14C as carbon dioxide by five days. Most of the bound 14C (>90%) arising from [phenyl-U-14C]carbofuran treatment of pretreated soil was extracted by 1 M sodium hydroxide and about half of the extracted 14C was precipitated with ‘humic acids’ after acidification. These and other results suggest that the major metabolic route for carbofuran in pretreated soils involves hydrolysis of the ester bond leading to (1) release of carbofuran phenol which rapidly binds to soil organic matter and, (2) release of the carbonyl moiety which quickly degrades to generate carbon dioxide. 相似文献
14.
WANG Junqiang 《干旱区科学》2016,8(3):350-363
Soil organic matter content in water-stable aggregates(WSA) in the arid ecosystems(abandoned agricultural lands especially) of China is poorly understood. In this study, we examined the WSA sizes and stability, and soil organic carbon(OC) and nitrogen(N) contents in agricultural lands with abandonment ages of 0, 3, 12, 20, 30 and 40 years, respectively, in the Minqin Oasis of Northwest China. The total soil OC and N contents at depths of 0–20, 20–40 and 40–60 cm in abandoned agricultural lands were compared to those in cultivated land(the control). Agricultural land abandonment significantly(P0.05) influenced the distribution of MWD(mean weight diameter), and OC and N contents. There were significant increases in MWD and the proportion of macroaggregates(sizes 0.25 mm) as the age of agricultural land abandonment increased. The effect of abandonment ages of agricultural lands on MWD was determined by the changes of OC and N accumulation in WSA sizes 2 mm. The total OC and N contents presented a stratification phenomenon across soil depths in this arid ecosystem. That is, both of them decreased significantly at depths of 0–20 and 40–60 cm while increased at the depth of 20–40 cm. The WSA sizes 0.053 mm had the highest soil OC and N contents(accounting for 51.41%–55.59% and 42.61%–48.94% of their total, respectively). Soil OC and N contents in microaggregates(sizes 0.053–0.25 mm) were the dominant factors that influenced the variations of total OC and N contents in abandoned agricultural lands. The results of this study suggested that agricultural land abandonment may result in the recovery of WSA stability and the shifting of soil organic matter from the silt+clay(0.053 mm) and microaggregate fractions to the macroaggregate fractions. However, agricultural land abandonment did not increase total soil OC and N contents in the short-term. 相似文献
15.
《干旱区科学》2017,(5)
Afforestation is conducive to soil carbon(C) sequestration in semi-arid regions. However, little is known about the effects of afforestation on sequestrations of total and labile soil organic carbon(SOC) fractions in semi-arid sandy lands. In the present study, we examined the effects of Caragana microphylla Lam. plantations with different ages(12-and 25-year-old) on sequestrations of total SOC as well as labile SOC fractions such as light fraction organic carbon(LFOC) and microbial biomass carbon(MBC). The analyzed samples were taken from soil depths of 0–5 and 5–15 cm under two shrub-related scenarios: under shrubs and between shrubs with moving sand dunes as control sites in the Horqin Sandy Land of northern China. The results showed that the concentrations and storages of total SOC at soil depths of 0–5 and 5–15 cm were higher in 12-and 25-year-old C. microphylla plantations than in moving sand dunes(i.e., control sites), with the highest value observed under shrubs in 25-year-old C. microphylla plantations. Furthermore, the concentrations and storages of LFOC and MBC showed similar patterns with those of total SOC at the same soil depth. The 12-year-old C. microphylla plantations had higher percentages of LFOC concentration to SOC concentration and MBC concentration to SOC concentration than the 25-year-old C. microphylla plantations and moving sand dunes at both soil depths. A significant positive correlation existed among SOC, LFOC, and MBC, implying that restoring the total and labile SOC fractions is possible by afforestation with C. microphylla shrubs in the Horqin Sandy Land. At soil depth of 0–15 cm, the accumulation rate of total SOC under shrubs was higher in young C. microphylla plantations(18.53 g C/(m~2·a); 0–12 years) than in old C. microphylla plantations(16.24 g C/(m~2·a); 12–25 years), and the accumulation rates of LFOC and MBC under shrubs and between shrubs were also higher in young C. microphylla plantations than in old C. microphylla plantations. It can be concluded that the establishment of C. microphylla in the Horqin Sandy Land may be a good mitigation strategy for SOC sequestration in the surface soils. 相似文献
16.
Gravel–sand mulch has been used for centuries to conserve water in the Loess Plateau of northwestern China. In this study, we assessed the influence of long-term(1996–2012) gravel–sand mulching of cultivated soils on total organic carbon(TOC), light fraction organic carbon(LFOC), microbial biomass carbon(MBC), total organic nitrogen(TON), particulate organic carbon(POC), mineral-associated organic carbon(MOC), permanganate-oxidizable carbon(KMn O4-C), and non-KMn O4-C at 0–60 cm depths. Mulching durations were 7, 11 and 16 years, with a non-mulched control. Compared to the control, there was no significant and consistently positive effect of the mulch on TOC, POC, MOC, KMn O4-C and non-KMn O4-C before 11 years of mulching, and these organic C fractions generally decreased significantly by 16 years. LFOC, TON and MBC to at a 0–20 cm depth increased with increasing mulching duration until 11 years, and then these fractions decreased significantly between 11 and 16 years, reaching values comparable to or lower than those in the control. KMn O4-C was most strongly correlated with the labile soil C fractions. Our findings suggest that although gravel–sand mulch may conserve soil moisture, it may also lead to long-term decreases in labile soil organic C fractions and total organic N in the study area. The addition of manure or composted manure would be a good choice to reverse the soil deterioration that occurs after 11 years by increasing the inputs of organic matter. 相似文献
17.
Soil labile organic carbon(C) plays an important role in improving soil quality. The relatively stable fractions of soil organic C(SOC) represent the bulk of SOC, and are also the primary determinant of the long-term C balance of terrestrial ecosystems. Different land use types can influence the distribution patterns of different SOC fractions. However, the underlying mechanisms are not well understood. In the present study, different fractions of SOC were determined in two land use types: a grazed grassland(established on previously cultivated cropland 25 years ago, GG) and a long-term cultivated millet cropland(MC). The results showed that C concentration and C storage of light fractions(LF) and heavy fractions(HF) presented different patterns along the soil profiles in the two sites. More plant residues in GG resulted in 91.9% higher LF storage at the 0–10 cm soil depth, further contributed to 21.9% higher SOC storage at this soil depth; SOC storage at 20–60 cm soil depth in MC was 98.8% higher than that in GG, which could be mainly attributed to the HF storage 104.5% higher than in GG. This might be caused by the long-term application of organic manure, as well as the protection from plough pan and silt- and clay-sized particles. The study indicated that different soil management practices in this region can greatly influence the variations of different SOC fractions, while the conventional tillage can greatly improve the storage of SOC by increasing heavy fractions. 相似文献
18.
长期定位施肥对旱作农田土壤有机碳及其组分的影响 总被引：1，自引：0，他引：1
基于田间定位试验,研究了长期施肥对旱作冬小麦农田土壤有机碳及其组分的影响,试验包括4个处理:不施肥(CK)、氮磷配施(NP)、化肥与有机肥配施(NPM)以及长期休闲地(BL)。结果表明:长期持续施肥30年后,在0~30 cm土层,NPM处理土壤有机碳、微生物量碳、潜在矿化碳以及碳库管理指数分别较CK提高了42.2%、55.9%、40.9%和40.0%(P0.05),NP处理土壤有机碳和微生物量碳与CK差异不显著,潜在矿化碳和碳库管理指数分别提高了29.1%和20.0%(P0.05),施肥对两种活性有机碳含量的影响在15~30 cm土层表现更加显著;与种植作物相比,长期休闲显著降低了土壤潜在矿化碳含量,BL处理较CK降低了20.5%(P0.05)。相关性分析表明,土壤有机碳、潜在矿化碳、微生物量碳以及碳库管理指数两两之间存在着显著的相关性,且有机碳组分含量与土壤有机碳含量在处理间变化具有一致性(除NP处理外),两种活性有机碳相对含量在各处理间差异均不显著。总的来说,长期持续施入有机肥能够有效地增加旱作农田土壤有机碳同时增加其活性组分,有助于培肥地力和土壤固碳。 相似文献
19.
人工防护林对风沙土有机碳动力学的影响 总被引：1，自引：0，他引：1
选取塔里木沙漠公路沿线定植年限为5、7、10、13、16 a的防护林,运用物理化学提取法及傅里叶变换红外光谱仪,研究人工防护林对风沙土发育过程中土壤有机碳动力学的影响。结果表明:(1)随定植年限增加,土壤碳储量变化不大;(2)土壤有机碳在0~50 cm随深度增加而降低,50 cm以下变化不大;(3)随防护林定植年限的增加,表层土壤(0~10 cm)中总有机碳(TOC)、微团聚体有机碳(OCMIA)、腐殖质有机碳(OCHS)、抗氧化性(OCNa Cl O)和抗酸解性有机碳(OCHCl)均有所升高,其中TOC、OCMIA、OCHS逐年增加,而OCNa Cl O和OCHCl在5~7 a时增加较快,以后趋于稳定,且各碳组分(OCHCl除外)在不同定植年限防护林风沙土间的差异极显著(P0.01),OCHCl差异显著(0.01P0.05);(4)所有碳组分极显著相关,其中OCMIA、OCHS与TOC的相关性比OCHCl、OCNa Cl O高;(5)惰性碳库中OCMIA和OCNa Cl O占总有机碳的比例较高,OCHS相对含量随定植年限增加而升高;(6)腐殖质结构中C=O相对含量(C=O/C-O-C)先降低后升高,脂族链聚亚甲基碳含量占末端甲基碳的比例(CH2/CH3)7 a时最高,后3个年限变化不大。因此,人工防护林引起了土壤有机碳累积,特别是惰性碳库在表层累积,腐殖化程度增加,提高了土壤固碳能力并促进了风沙土的发育。 相似文献
20.
Revegetation is a traditional practice widely used for soil protection. We evaluated the effect of natural revegetation succession on soil chemical properties and carbon fractions (particulate organic carbon (POC), humus carbon (HS-C), humic acid carbon (HA-C) and fulvic acid carbon (FA-C)) on the Loess Plateau of China. The vegetation types, in order from the shortest to the longest enclosure duration, were: (a) abandoned overgrazed grassland (AbG3; 3 years); (b) Hierochloe odorata Beauv. (HiO7; 7 years); (c) Thymus mongolicus Ronnm (ThM15; 15 years); (d) Artemisia sacrorum Ledeb (AtS25; 25 years); (e) Stipa bungeana Trin Ledeb (StB36; 36 years) and (f) Stipa grandis P. Smirn (StG56; 56 years). The results showed that the concentrations of soil organic carbon, total nitrogen and available phosphorus increased with the increase of restoration time except for ThM15. The concentration of NH4-N increased in the medium stage of vegetation restoration (for ThM15 and AtS25) and decreased in the later stage (for StB36 and StG56). However, NO3-N concentration significantly increased in the later stage (for StB36 and StG56). Carbon fractions had a similar increasing trend during natural vegetation restoration. The concentrations of POC, HS-C, FA-C and HA-C accounted for 24.5%–49.1%, 10.6%–15.2%, 5.8%–9.1% and 4.6%–6.1% of total carbon, respectively. For AbG3, the relative changes of POC, HS-C and FA-C were significantly higher than that of total carbon during the process of revegetation restoration. The higher relative increases in POC, HS-C and FA-C confirmed that soil carbon induced by vegetation restoration was sequestrated by higher physical and chemical protection. The increases of soil C fractions could also result in higher ecology function in semiarid grassland ecosystems. 相似文献