滨海滩涂不同覆盖度下盐地碱蓬生长特征及土壤呼吸速率变化  

Growth characteristics and soil respiration rates with different coverages of Suaeda salsa at coastal beaches

作　　者：李永涛[1] 王振猛[1] 魏海霞[1] 周健[1] 王莉莉[1] 张军 吕兴军 杨庆山[1] 王元波 LI Yongtao;WANG Zhenmeng;WEI Haixia;ZHOU Jian;WANG Lili;ZHANG Jun;LYU Xingjun;YANG Qingshan;WANG Yuanbo(Shandong Academy of Forestry Sciences/National Observation and Research Station of Chinese Forest Ecosystem of the Yellow River Delta,Jinan 250014,China;Binzhou University/Shandong Provincial Key Laboratory of Eco-Environmental Science for the Yellow River Delta,Binzhou 256603,China;Shandong Land and Space Ecological Restoration Center,Jinan 250014,China)

机构地区：[1]山东省林业科学研究院/黄河三角洲森林生态系统国家定位观测研究站,济南250014 [2]滨州学院/山东省黄河三角洲生态环境重点实验室,滨州256603 [3]山东省国土空间生态修复中心,济南250014

出　　处：《中国生态农业学报（中英文）》2023年第3期478-486,共9页Chinese Journal of Eco-Agriculture

基　　金：黄河三角洲土地利用安全野外科学观测研究站开放基金(YWZ2022-06);山东省黄河三角洲生态环境重点实验室开放基金项目(2022KFJJ02)资助。

摘　　要：为探究不同覆盖度下盐地碱蓬的生长特征及土壤呼吸速率变化规律,以黄河三角洲滨海滩涂典型的盐地碱蓬群落为研究对象,选取滩涂裸地区、低覆盖区、中覆盖区和高覆盖区4种样地,研究了不同覆盖度下盐地碱蓬的植株生长、根系分布及土壤呼吸速率变化间的差异。结果表明:盐地碱蓬不同覆盖区土壤的理化性质和植被生长状况差异明显,与滩涂裸地相比,盐地碱蓬不同覆盖区土壤含盐量和容重降低,土壤孔隙度和养分增加。盐地碱蓬的生长指标与覆盖度呈正相关,生物量、株高及分支数均随覆盖度的提高显著增加(P<0.05)。其中,盐地碱蓬地下部分生物量主要集中在0~20 cm表层土壤中,呈现浅层化分布;且均以2~5 mm粗度根系为主,分别占低、中和高覆盖区地下生物量的72.53%、59.72%和39.30%。细根的根长、表面积、根尖数、分支数和交叉数均随覆盖度的提高而逐步增大,且不同覆盖区之间差异显著(P<0.05)。不同覆盖区内土壤呼吸速率表现为高覆盖区>中覆盖区>低覆盖区>裸地区,并具有明显的日变化,呈现出低-高-低的单峰曲线,最大值出现在12:00—14:00。相关性分析表明,土壤含盐量与盐地碱蓬各生长指标呈显著或极显著负相关,是主要限制因子,而土壤呼吸速率与植株各生长指标均呈极显著正相关。本研究结果可为黄河三角洲滨海滩涂植被恢复与生态修复提供理论依据。Coastal beaches are one of the most important components of coastal wetlands.Studies on vegetation growth characteristics and soil respiration in coastal beaches are essential for evaluation of the ecological and environmental functions of coastal wetlands.In the present study,differences in vegetation growth,root distribution,and soil respiration rate of Suaeda salsa with four coverage types(bare flat and low-coverage,medium-coverage,and high-coverage)were determined to explore the impact of vegetation coverage on the growth characteristics of S.salsa and soil respiration rates at the coastal beach of the Yellow River Delta.Significant differences were observed in the soil physicochemical properties and vegetation growth of S.salsa on coastal beaches with different coverages.Soil salt content and bulk density were lower in various coverage areas than those in bare flats,whereas soil porosity and nutrients contents were greater than those in bare flats.The growth indices of S.salsa,such as biomass,plant height,and branch number,were positively correlated with vegetation coverage(P<0.05),indicating better growth in soils with higher vegetation coverage.The underground S.salsa biomass in saline land was mainly distributed in the 0–20 cm soil layer,showing a shallow distribution pattern.Roots with a 2–5 cm diameter were dominant components,accounting for 72.53%,59.72%,and 39.30%of the underground biomass in the low-,medium-,and high-coverage areas,respectively.The root length,surface area,tip number,branch number,and cross number of fine roots increased with coverage,and the differences in these indices between the different coverage areas were significant(P<0.05).Soil respiration rates were low,at 0.26–1.01μmol·m-2·s-1,owing to the low soil organic carbon content and microbial activity in the study area.Soil respiration rates were significantly affected by vegetation coverage and showed an increasing order of value with coverage(high-coverage area>medium-coverage area>low-coverage area>bare area).Soil resp

关 键 词：覆盖度 盐地碱蓬 植株生长 根系分布 土壤呼吸速率 

分 类 号：S156.4[农业科学—土壤学]