青海高寒沼泽湿地红色沉积物的物质组成及其自燃引火机制
收稿日期: 2025-09-09
修回日期: 2026-01-25
网络出版日期: 2026-08-07
基金资助
省部共建三江源生态与高原农牧业国家重点试验室自主课题“火干扰对高寒草甸冻土和植被的影响”(2024-ZZ-09)
Material composition and spontaneous ignition mechanism of red sediments in Qinghai alpine swamp wetlands
Received date: 2025-09-09
Revised date: 2026-01-25
Online published: 2026-08-07
青海高寒沼泽湿地春季野火频发,其自燃机制尚不明确。采集青海省天峻县木里镇阿子沟野火频发区湿地坑底0~0.2 cm红色沉积物,应用场发射扫描电镜-能谱(FE-SEM-EDS)、同步热分析(STA)和X射线光电子能谱(XPS),分析其微观形貌、元素组成、热稳定性及铁化学态,从铁氧化物化学特性角度,揭示湿地坑底红色沉积物的燃烧属性及其自燃引火的可能性。结果表明:1)研究区沉积物主要由羟基氧化铁(FeOOH)和有机质(OM)组成,呈多孔蜂窝状结构;2)实验室表观燃点约213 ℃,有机质燃烧是主要放热过程;3)铁元素能谱精细结构证实铁以FeOOH形态为主;4)FeOOH本身不可燃,但其凭借高比表面积和表面羟基特性,可作为“光热转化介质”吸附富集有机质。青海高寒沼泽湿地红色沉积物具备在特定条件下(如冰透镜聚焦阳光)将光能转化为热能并引发有机质阴燃的潜力,其引火机制是季节性冻融、微地形、太阳辐射与特殊物质属性耦合的结果,为高寒湿地自然火灾成因的研究提供了科学依据。
全小龙 , 陈梦词 , 乔有明 . 青海高寒沼泽湿地红色沉积物的物质组成及其自燃引火机制[J]. 林草资源研究, 2026 , 0(1) : 58 -66 . DOI: 10.13466/j.cnki.lczyyj.2026.01.006
Spring wildfires frequently occur in the alpine swamp wetlands of the Qinghai-Tibet Plateau,yet their spontaneous ignition mechanism remains unclear.This study reveal the combustion properties of red sediments at the bottom of wetland pits and their potential as a spontaneous ignition source from the perspective of the chemical characteristics of iron oxides.Red sediment samples(at a depth from 0 to 0.2 cm)were collected from the pit bottom in the fire-prone area of Azigou,Muli Town,Tianjun County,Qinghai Province.Their micromorphology,elemental composition,thermal stability,and iron chemical states were analyzed using field emission scanning electron microscopy coupled with energy-dispersive spectroscopy(FE-SEM-EDS),simultaneous thermal analysis(STA),and X-ray photoelectron spectroscopy(XPS).The results showed that:1)The sediments are mainly composed of iron oxyhydroxide(FeOOH),and organic matter(OM),exhibiting a porous honeycomb structure;2)The laboratory apparent ignition point is approximately 213 ℃,the combustion of organic matter is the main exothermic process;3)The fine structure of energy-dispersive X-ray spectroscopy confirms that iron mainly exists in the form of FeOOH;4)FeOOH is non-combustible however,owing to its high specific surface area and surface hydroxyl properties,it can act as a “photothermal conversion medium” to adsorb and enrich organic matter.The red sediments in the Qinghai alpine swamp wetlands have the potential to convert light energy into heat under specific conditions(e.g.,sunlight focused by ice lenses)and trigger the smoldering of organic matter.The ignition mechanism results from the coupling of seasonal freeze-thaws,micro-topography,solar radiation,and the special material attributes.This study provides a new perspective for understanding the causes of natural fires in alpine wetlands from a material basis standpoint.
Key words： natural wildfire; red sediment; FeOOH; photothermal conversion; ignition mechanism
| [1] | 何凡能, 杨帆, 王亚非. 过去千年中国森林和草地面积及空间格局重建[J]. 中国科学:地球科学, 2025, 55(1):95-110. |
| [2] | 孙华方, 李希来, 金立群, 等. 高寒沼泽湿地植被特征和土壤养分对自然野火的响应[J]. 草地学报, 2024, 32(8):2557-2566. |
| [3] | Wieting C, Ebel B A, Singha K. Quantifying the effects of wildfire on changes in soil properties by surface burning of soils from the Boulder Creek Critical Zone Observatory[J]. Journal of Hydrology:Regional Studies, 2017, 13:43-57. |
| [4] | Song Zhaopeng, Li Zhaolei, Luo Yiqi, et al. Allocation strategies of carbon,nitrogen and phosphorus following a gradient of wildfire severities[J]. Journal of Plant Ecology, 2022, 15(2):347-358. |
| [5] | 杨光, 王欣宇, 马运佳, 等. 火烈度对落叶松林土壤微生物量和群落组成的影响[J]. 林草资源研究, 2024(6):35-44. |
| [6] | Williams-Jara G M, Espinoza-Tenorio A, Monzón-Alvarado C, et al. Fires in coastal wetlands:a review of research trends and management opportunities[J]. Wetlands, 2022, 42:56. |
| [7] | 王娟, 陈文业, 谈嫣蓉, 等. 火干扰对内陆荒漠湿地芦苇群落特征的影响[J]. 干旱区地理, 2020, 43(3):770-776. |
| [8] | Kouki J, Hyv?rinen E, Lappalainen H, et al. Landscape context affects the success of habitat restoration:large-scale colonization patterns of saproxylic and fire-associated species in boreal forests[J]. Diversity and Distributions, 2012, 18(4):348-355. |
| [9] | Wang C, Wang G, Wang Y, et al. Fire alters vegetation and soil microbial community in alpine meadow[J]. Land Degradation & Development, 2016, 27(5):1379-1390. |
| [10] | 李宏林, 周浪敏, 薛静, 等. 高寒沼泽化草甸群落常见种对土壤水分条件的响应研究[J]. 生态科学, 2023, 42(4):1-8. |
| [11] | 黄永生, 夏兴生, 周强, 等. 青海省草原火灾时空格局及成因调查研究[J]. 地理科学进展, 2023, 42(10):1973-1983. |
| [12] | McColl-Gausden S, Bennett L, Clarke H, et al. The fuel-climate-fire conundrum:how will fire regimes change in temperate eucalypt forests under climate change?[J]. Global Change Biology, 2022, 28(17):5211-5226. |
| [13] | 周怡志, 李希来, 姚文治, 等. 自然野火对高寒沼泽湿地土壤有机碳组分的影响[J]. 草地学报, 2025, 33(6):1771-1781. |
| [14] | 周怡志. 高寒湿地自然火灾对植被和土壤特征的影响及其成因分析[D]. 西宁: 青海大学, 2025. |
| [15] | Detsis V, Efthimiou G, Theodoropoulou O, et al. Determination of the environmental factors that affect the growth and survival of Greek fir seedlings[J]. Land, 2020, 9(4):100. |
| [16] | Beverly J L, Leverkus S E R, Cameron H, et al. Stand-level fuel reduction treatments and fire behaviour in Canadian boreal conifer forests[J]. Fire, 2020, 3(3):35. |
| [17] | Schmidt I B, Fidelis A, Miranda H S, et al. How do the wets burn?Fire behavior and intensity in wet grasslands in the Brazilian savanna[J]. Brazilian Journal of Botany, 2017, 40(1):167-175. |
| [18] | Chiono L A, Fry D L, Collins B M, et al. Landscape-scale fuel treatment and wildfire impacts on carbon stocks and fire hazard in California spotted owl habitat[J]. Ecosphere, 2017, 8(1):e01648. |
| [19] | Just M G, Hohmann M G, Hoffmann W A. Where fire stops:vegetation structure and microclimate influence fire spread along an ecotonal gradient[J]. Plant Ecology, 2016, 217(6):631-644. |
| [20] | 赵平欣, 马远帆, 李哲瀚, 等. 土壤微量元素、细菌群落及生物酶对林火烟气沉降的响应[J]. 生态学报, 2025, 45(14):6973-6984. |
| [21] | Colombo C, Palumbo G, Sellitto V M, et al. Stability of coprecipitated natural humic acid and ferrous iron under oxidative conditions[J]. Journal of Geochemical Exploration, 2015, 151:50-56. |
| [22] | 周宏光. 载纳米水合氧化铁复合半焦的研制及其除磷性能研究[D]. 重庆: 西南大学, 2014. |
| [23] | 江家彬, 祝贞科, 林森, 等. 针铁矿吸附态和包裹态有机碳在稻田土壤中的矿化及其激发效应[J]. 土壤学报, 2021, 58(6):1530-1539. |
| [24] | Chang Ting, Sun Jing, Li Shiwen, et al. Oxygen adsorption and activation control the photochemical activity of common iron oxyhydroxide polymorphs in mediating oxytetracycline degradation under visible light[J]. Journal of Colloid and Interface Science, 2025, 683(2):565-577. |
| [25] | McGranahan D A, Zopfi M E, Yurkonis K A. Weather and fuel as modulators of grassland fire behavior in the Northern Great Plains[J]. Environmental Management, 2023, 71(5):940-949. |
| [26] | Kong Jianjian, Yang Jian, Cai Wenhua. Topography controls post-fire changes in soil properties in a Chinese boreal forest[J]. Science of the Total Environment, 2019, 651(Pt 2):2662-2670. |
| [27] | Fultz L M, Moore-Kucera J, Dathe J, et al. Forest wildfire and grassland prescribed fire effects on soil biogeochemical processes and microbial communities:two case studies in the semi-arid Southwest[J]. Applied Soil Ecology, 2016, 99:118-128. |
| [28] | Owiti D A, Tazisong I A, Senwo Z N. Microbial and organic matter patterns in a prescribed burned and thinned managed forest ecosystem[J]. Ecosphere, 2017, 8(12):e01962. |
/
| 〈 |
|
〉 |
