Variation Characteristics of Organic Carbon and Fractions in Soils along the Altitude Gradient in Nanling Mountains
-
摘要:
目的 为了解我国亚热带山地土壤有机碳及组分海拔梯度变化规律及影响因素。 方法 以南岭国家级自然保护区不同海拔(400 ~ 1650 m)山地土壤为研究对象,调查了土壤有机碳及组分在不同土层深度的分布及密度特征,分析了土壤理化因子的影响。 结果 (1)总有机碳、易氧化碳、颗粒有机碳、惰性有机碳含量在相对较高海拔土壤中的含量整体更高,并在针阔混交林土壤中出现最大值,而水溶性有机碳含量则在低海拔的沟谷常绿阔叶林土壤中最高。(2)有机碳及组分含量随土层深度的增加呈明显下降趋势,随海拔变化幅度最大的组分为水溶性有机碳,随深度变化幅度最大的为颗粒有机碳,不同组分占总有机碳的比例在不同海拔和深度上的变化规律有所差异。(3)南岭山地土壤有机碳密度范围为8.81 ~ 26.59 kg m−2,整体略高于与其位置相近的山地土壤,有机碳及组分密度随海拔变化趋势与各自在土壤中的含量分布规律较为类似。(4)pH、黏粒含量、全氮与有机碳及组分含量的相关性较好,RDA分析结果表明全氮、全磷与土壤含水率对有机碳及组分变化的解释量占比较高。 结论 南岭山地土壤有机碳及组分具有明显的海拔梯度变化特征,土壤理化性质是影响有机碳及组分分布的重要因素。 Abstract:Objective Mountainous soil carbon (C) pool is an important component of terrestrial C pool, which plays a key role in adjusting C cycle of ecosystem and mitigating global climate change. Altitude gradient is a governing factor in influencing the content and property of mountainous soil C. Exploring the distribution characteristics of organic C and fractions in mountainous soil of different altitude gradients is of great significance for reasonably estimating the soil organic C pool and predicting its sensitivity to climate change. This study aims to investigate the variation characteristics of organic C and fractions in soils along the altitude gradient of subtropical mountainous and the related influencing factors. Method Gully evergreen broad-leaved forest (< 800 m), montane evergreen broad-leaved forest (800-1200 m), theropencedrymion (1200-1500 m), alpine meadow and montane elfin (> 1500 m) at different altitude gradients and depths (0-10, 10-20, 20-40, 40-60, and 60-100 cm) in Nanling national natural reserve were selected as the study objects, the distribution and density characteristics of soil organic C and various fractions (Water-dissolved soil organic C, WSOC; readily oxidizable carbon, ROC; particle organic carbon, POC, recalcitrant carbon, RC) were examined, as well as soil physicochemical properties including pH, mechanical composition, soil moisture content and nutrient indicators (total nitrogen, total phosphorus and total potassium). Result The results showed that: (1) the soils in Nanling mountains were extremely acidic or strongly acidic, and the pH values were relatively higher in the soil of montane evergreen broad-leaved forest. Sand was the predominant fraction of the mechanism composition and the proportion of clay particles decreased gradually with the increase of altitude. The contents of total nitrogen and total phosphorus in alpine meadow and montane elfin soils were significantly higher than those in the soils at other altitudes, while the content of total potassium increased first and then decreased with the increasing of altitude; (2) the content of SOC, ROC, POC and RC was relatively higher at high altitudes and the maximum values appeared in the soil of gully evergreen broad-leaved forest with low altitude, while the maximum values of WSOC appeared in the soil of gully evergreen broad-leaved forest with relatively low altitude. The content of soil organic C and fractions decreased obviously with the increase of depth. Among the various soil C fractions, WSOC varied the most with altitude, while POC varied the most with depth. The variation regularity of the proportions of different organic C fractions in total organic C were also different to some extent; (3) the soil organic C density of Nanling mountains varied in the range of 8.81-26.59 kg m−2, which was slightly higher than that of the nearby mountains overall. The variation tendency of different organic C fractions with altitude and depth was similar to that of total organic C; (4) pH, clay content, total nitrogen showed good relevance with soil organic C and fractions. The RDA results showed that TN, TP and soil moisture content had high proportions in explaining the variation of oil organic C and fractions. Conclusion There existed obvious difference in the organic C and fraction content of soils at different altitudes in Nanling mountains. Soil property is an important aspect influencing the distribution characteristics of organic C, while other environmental factors should also be considered in the future study. -
Key words:
- Nanling mountains /
- Soil organic carbon /
- Carbon fraction /
- Altitude gradient
-
表 1 采样地基本情况
Table 1. Basic information of the sampling plots
样地
Sample plot海拔(m)
Altitude坡度(°)
Slope土壤类型
Soil type植被类型
Vegetation type优势植被
Dominant vegetationS1 402 8 山地红壤 沟谷常绿阔叶林 广东润楠 Machilus kwangtungensis、石栎 Lithocarpus glaber、鹿角锥Castanopsislamontii、赤楠 Syzygium buxifolium S2 798 15 山地红壤 沟谷常绿阔叶林 广东润楠Machilus kwangtungensis、青冈Cyclobalanopsis glauca罗浮锥Castanopsis fabri S3 920 18 山地黄壤 山地常绿阔叶林 甜槠 Castanopsis eyrei、水青冈 Fagus longipetiolata、米锥 Castanopsis chinensis S4 1184 10 山地黄壤 山地常绿阔叶林 鹿角锥 Castanopsis lamontii、青冈 Cyclobalanopsis glauca、千年桐 Vernicia montana、罗浮锥 Castanopsis fabri、甜槠 Castanopsis eyrei S5 1364 15 山地黄壤 针阔混交林 广东松 Pinus Kwangtungensis、荷木Schima superba、马尾松 Pinus massoniana、甜槠 Castanopsis eyrei、青冈 Cyclobalanopsis glauca S6 1396 15 山地黄壤 针阔混交林 荷木 Schima superba、广东松 Pinus Kwangtungensis、甜槠Castanopsis eyrei、长苞铁杉 Tsuga longibracteata S7 1536 5 山地草甸土 山顶草甸 五节芒 Miscanthus floridulus S8 1653 8 山地黄壤 山顶矮林 野茉莉Styrax japonicus、少花桂 Cinnamomum pauciflorum、青冈 Cyclobalanopsis glauca 表 2 不同土壤有机碳组分占总有机碳比例
Table 2. The percentages of different fractions of soil organic carbon in the total soil organic carbon
组分
Fraction土层
Soil layer采样点
Sampling siteS1
(%)S2
(%)S3
(%)S4
(%)S5
(%)S6
(%)S7
(%)S8
(%)WSOC 0 ~ 10 2.42 ± 1.23 0.72 ± 0.20 1.02 ± 0.16 1.04 ± 0.48 0.55 ± 0.19 0.24 ± 0.06 0.23 ± 0.02 1.34 ± 0.48 10 ~ 20 2.75 ± 0.96 1.03 ± 0.36 1.42 ± 0.17 0.92 ± 0.09 1.07 ± 0.23 0.50 ± 0.17 0.32 ± 0.13 1.37 ± 0.29 20 ~ 40 3.79 ± 0.84 3.41 ± 0.64 1.61 ± 0.64 1.29 ± 0.34 0.75 ± 0.19 0.88 ± 0.03 0.43 ± 0.08 1.38 ± 0.40 40 ~ 60 6.31 ± 2.68 2.75 ± 1.52 2.22 ± 0.11 1.13 ± 0.26 1.23 ± 0.30 0.96 ± 0.50 0.65 ± 0.11 0.85 ± 0.66 60 ~ 100 3.79 ± 3.35 2.16 ± 0.64 2.09 ± 0.35 2.25 ± 0.76 1.54 ± 0.49 1.84 ± 1.81 0.89 ± 0.12 2.22 ± 1.82 ROC 0 ~ 10 4.69 ± 0.04 3.32 ± 1.54 3.50 ± 0.29 3.33 ± 0.71 3.63 ± 1.04 4.88 ± 0.47 4.02 ± 1.07 3.76 ± 0.23 10 ~ 20 4.93 ± 0.45 3.29 ± 0.95 3.37 ± 0.81 3.93 ± 1.60 4.60 ± 0.69 5.66 ± 0.81 5.00 ± 0.79 2.67 ± 1.25 20 ~ 40 5.27 ± 0.77 4.89 ± 1.45 3.81 ± 0.96 4.29 ± 1.60 3.68 ± 0.77 6.83 ± 3.18 4.75 ± 1.34 2.94 ± 1.38 40 ~ 60 6.79 ± 3.24 7.38 ± 3.03 4.09 ± 2.17 4.34 ± 0.74 2.84 ± 0.18 8.83 ± 6.50 4.03 ± 0.66 2.80 ± 0.26 60 ~ 100 5.70 ± 0.50 5.10 ± 1.89 3.75 ± 1.47 8.73 ± 5.25 4.11 ± 2.33 9.36 ± 1.87 3.84 ± 1.90 2.66 ± 1.20 POC 0 ~ 10 68.65 ± 2.92 41.35 ± 16.09 58.31 ± 4.43 64.71 ± 26.11 56.85 ± 29.80 51.18 ± 2.11 59.68 ± 4.5 64.75 ± 9.91 10 ~ 20 55.75 ± 16.95 47.97 ± 21.41 59.57 ± 14.89 71.43 ± 15.21 69.85 ± 9.35 37.18 ± 2.22 62.05 ± 3.38 51.06 ± 8.23 20 ~ 40 34.73 ± 9.71 40.95 ± 8.67 50.00 ± 14.33 68.62 ± 1.84 62.83 ± 10.03 37.35 ± 23.07 57.31 ± 17.9 48.85 ± 9.65 40 ~ 60 26.93 ± 0.00 50.62 ± 6.53 37.9 ± 22.58 65.14 ± 3.42 48.27 ± 17.85 37.06 ± 20.08 53.08 ± 2.85 43.91 ± 19.58 60 ~ 100 26.06 ± 0.53 42.62 ± 25.58 55.92 ± 13.49 40.14 ± 5.92 54.73 ± 19.95 30.31 ± 3.70 62.21 ± 6.04 55.02 ± 11.33 RC 0 ~ 10 64.01 ± 13.78 40.93 ± 12.08 65.41 ± 7.19 47.09 ± 9.87 46.68 ± 33.9 54.95 ± 8.49 46.87 ± 8.53 49.28 ± 2.28 10 ~ 20 55.57 ± 8.125 48.56 ± 14.73 51.46 ± 2.67 66.5 ± 13.11 54.56 ± 17.51 50.58 ± 7.83 42.58 ± 12.83 40.38 ± 7.63 20 ~ 40 57.38 ± 18.84 63.21 ± 9.74 32.46 ± 6.06 50.19 ± 5.75 45.11 ± 27.67 40.18 ± 8.33 46.58 ± 7.88 37.51 ± 8.18 40 ~ 60 41.05 ± 12.36 34.48 ± 9.39 56.63 ± 17.83 46.67 ± 6.19 45.76 ± 24.17 43.22 ± 19.63 38.74 ± 14.83 31.35 ± 10.13 60 ~ 100 42.58 ± 19.70 52.92 ± 4.55 45.39 ± 4.45 58.50 ± 3.70 44.69 ± 11.52 52.23 ± 13.34 36.87 ± 14.81 35.02 ± 13.91 注:WSOC,水溶性有机碳;ROC,易氧化有机碳;POC,颗粒有机碳;RC,惰性有机碳。下同。 表 3 有机碳及组分与土壤理化性质相关性矩阵
Table 3. Correlation matrix of organic carbon, organic carbon fractions, and soil physiochemical property indicators.
pH 容重
SBD含水率
SMC砂粒
Sand粉粒
Silt黏粒
Clay全氮
TN全磷
TP全钾
TKSOC WSOC ROC POC RC pH 1 容重 −0.110 1 含水率 −0.208* −0.054 1 砂粒 0.045 0.299** 0.152 1 粉粒 −0.029 0.028 −0.048 −0.440** 1 黏粒 0.332** −0.120 −0.182* 0.018 0.020 1 全氮 −0.172 −0.032 0.382** 0.013 0.118 −0.175 1 全磷 −0.065 −0.006 0.289** −0.02 0.062 −0.020 0.737** 1 全钾 −0.062 −0.117 0.400 0.012 0.027 −0.062 −0.184* −0.184* 1 SOC −0.494** −0.120 0.275** −0.111 0.237** −0.366** 0.355** 0.182 0.245** 1 WSOC −0.363** −0.071 −0.057 −0.144 0.077 0.045 0.009 0.000 −0.001 0.260** 1 POC −0.408** −0.100 0.290** −0.135 0.311** −0.308** 0.241** 0.067 0.220* 0.866** 0.140 1 POC −0.364** −0.076 0.185 −0.620 0.168 −0.280** 0.788** 0.520* −0.101 0.642** 0.219* 0.510** 1 RC −0.414** −0.193* 0.328** −0.160 0.157 −0.356** 0.282** 0.073 0.173 0.783** 0.186* 0.685** 0.643** 1 注:SBD, Soil bulk density; SMC, Soil moisture content; TN, Total nitrogen; TP, Total phosphorus; TK, Total, potassium; *,P < 0.05;* *,P < 0.01。 -
[1] Terrer C, Phillips R P, Hungate B A, et al. A trade-off between plant and soil carbon storage under elevated CO2[J]. Nature, 2021, 591(7851): 599 − 603. doi: 10.1038/s41586-021-03306-8 [2] Zhao J, Ma J, Hou M, et al. Spatial–temporal variations of carbon storage of the global forest ecosystem under future climate change[J]. Mitigation and Adaptation Strategies for Global Change, 2020, 25(4): 603 − 624. doi: 10.1007/s11027-019-09882-5 [3] Han L F, Sun K, Jin J, et al. Some concepts of soil organic carbon characteristics and mineral interaction from a review of literature[J]. Soil Biology and Biochemistry, 2016, 94: 107 − 121. doi: 10.1016/j.soilbio.2015.11.023 [4] Luo Z, Feng W, Luo Y, et al. Soil organic carbon dynamics jointly controlled by climate, carbon inputs, soil properties and soil carbon fractions[J]. Global Change Biology, 2017, 23(10): 4430 − 4439. doi: 10.1111/gcb.13767 [5] 张方方, 岳善超, 李世清. 土壤有机碳组分化学测定方法及碳指数研究进展[J]. 农业环境科学学报, 2021, 40(2): 252 − 259. doi: 10.11654/jaes.2020-0886 [6] 刘春增, 常单娜, 李本银, 等. 种植翻压紫云英配施化肥对稻田土壤活性有机碳氮的影响[J]. 土壤学报, 2017, 54(3): 657 − 669. [7] Liu X, Chen D T, Yang T, et al. Changes in soil labile and recalcitrant carbon pools after land-use change in a semi-arid agro-pastoral ecotone in Central Asia[J]. Ecological Indicators, 2020, 110: 105925. doi: 10.1016/j.ecolind.2019.105925 [8] 王深华, 江 军, 刘丰彩, 等. 中国成熟天然林土壤有机碳垂直分异特征[J]. 应用生态学报, 2021, 32(7): 2371 − 2377. [9] Kučerík J, Tokarski D, Demyan M S, et al. Linking soil organic matter thermal stability with contents of clay, bound water, organic carbon and nitrogen[J]. Geoderma, 2018, 316: 38 − 46. doi: 10.1016/j.geoderma.2017.12.001 [10] Jia Y, Kuzyakov Y, Wang G, et al. Temperature sensitivity of decomposition of soil organic matter fractions increases with their turnover time[J]. Land Degradation & Development, 2020, 31(5): 632 − 645. [11] 柯娴氡, 张 璐, 苏志尧. 粤北亚热带山地森林土壤有机碳沿海拔梯度的变化[J]. 生态与农村环境学报, 2012, 28(2): 151 − 156. doi: 10.3969/j.issn.1673-4831.2012.02.007 [12] 习 丹, 余泽平, 熊 勇, 等. 江西官山常绿阔叶林土壤有机碳组分沿海拔的变化[J]. 应用生态学报, 2020, 31(10): 3349 − 3356. [13] 向慧敏, 温达志, 张玲玲, 等. 鼎湖山森林土壤活性碳及惰性碳沿海拔梯度的变化[J]. 生态学报, 2015, 35(18): 6089 − 6099. [14] 秦海龙, 贾重建, 卢 瑛, 等. 广东罗浮山土壤有机碳储量与组分垂直分布特征[J]. 西南林业大学学报, 2018, 38(3): 108 − 115. [15] 刘迎春, 于贵瑞, 王秋凤, 等. 基于成熟林生物量整合分析中国森林碳容量和固碳潜力[J]. 中国科学:生命科学, 2015, 45(2): 210 − 222. [16] 刘安世. 广东土壤[M]. 北京: 科学出版社, 1993. [17] 宗天韵, 周玮莹, 周 平. 南岭山地1968到2015年降雨的时空变化特征研究[J]. 生态科学, 2019, 38(2): 182 − 190. [18] Nelson D W, Sommers L E. Total carbon, organic carbon, and organic matter. Laboratory methods. In: Methods of soil analysis. Part 2. 2nd ed. Agron. Monogr. No. 9 ASA and SSSA [M]. Wisconsin: Madison, 1982: 539 - 579. [19] Huggins D R, Clapp C E, Allmaras R R, et al. Carbon dynamics in corn soybean sequences as estimated from natural 13C abundance[J]. Soil Science Society of America Journal, 1998, 62: 195 − 203. doi: 10.2136/sssaj1998.03615995006200010026x [20] Kantola I B, Masters M D, DeLucia E H. Soil particulate organic matter increases under perennial bioenergy crop agriculture[J]. Soil Biology and Biochemistry, 2017, 113: 184 − 191. doi: 10.1016/j.soilbio.2017.05.023 [21] 鲁如坤. 土壤农业化学分析方法[M]. 北京: 中国农业科技出版社, 2000. [22] Dai W H, Huang Y. Relation of soil organic matter concentration to climate and altitude in zonal soils of China[J]. Catena, 2006, 65(1): 87 − 94. doi: 10.1016/j.catena.2005.10.006 [23] 王春燕, 何念鹏, 吕瑜良. 中国东部森林土壤有机碳组分的纬度格局及其影响因子[J]. 生态学报, 2016, 36(11): 3176 − 3188. [24] 王怡雯, 许 浩, 茹淑华, 等. 有机肥连续施用对土壤剖面有机碳分布的影响及其与重金属的关系[J]. 生态学杂志, 2019, 38(5): 1500 − 1507. [25] 吴小刚, 王文平, 李 斌, 等. 中亚热带森林土壤有机碳的海拔梯度变化[J]. 土壤学报, 2020, 57(6): 1539 − 1547. [26] Leifeld J, Bassin S, Conen F, et al. Control of soil pH on turnover of belowground organic matter in subalpine grassland[J]. Biogeochemistry, 2013, 112(1): 59 − 69. [27] Kalbitz K, Solinger S, Park J H, et al. Controls on the dynamics of dissolved organic matter in soils: A review[J]. Soil science, 2000, 165(4): 277 − 304. doi: 10.1097/00010694-200004000-00001