干旱区地理 ›› 2022, Vol. 45 ›› Issue (6): 1899-1907.doi: 10.12118/j.issn.1000-6060.2022.026 cstr: 32274.14.ALG2022026
收稿日期:
2022-01-17
修回日期:
2022-04-15
出版日期:
2022-11-25
发布日期:
2023-02-01
作者简介:
郭鑫(1998-),女,硕士研究生,主要从事水土保持等方面的研究. E-mail: 基金资助:
GUO Xin(),WEI Tianxing(
),CHEN Yuxuan,SHA Guoliang,REN Kang,YU Huan
Received:
2022-01-17
Revised:
2022-04-15
Published:
2022-11-25
Online:
2023-02-01
摘要:
为探究不同植被土壤碳(C)、氮(N)、磷(P)化学计量特征及其影响因素,以黄土丘陵区油松、刺槐、沙棘和草地4种典型退耕恢复植被0~100 cm土壤为研究对象,分析不同植被土壤有机碳(SOC)、全氮(STN)、全磷(STP)含量及其化学计量特征。结果表明:(1) 不同恢复植被对土壤养分含量有显著影响,刺槐的SOC、STN最高,油松的SOC、STN最低,STP表现为草地>刺槐>油松>沙棘。(2) 不同恢复植被土壤养分具有“表聚性”,随土层深度增加,SOC和STN含量呈下降趋势,而STP的变异性较弱。特别是刺槐的SOC和STN在60~100 cm呈增加趋势。(3) 不同恢复植被土壤SOC:STN(C:N)、SOC:STP(C:P)差异不显著(P>0.05),刺槐的土壤STN:STP(N:P)显著高于其他植被类型(P<0.05),土壤C:N、C:P、N:P均低于全球及全国平均水平,研究区有机质的分解速率较快,P的有效性高,植被生长主要受N元素限制。(4) 研究区土壤C:N、C:P和N:P主要受SOC和STN影响;土壤养分与土壤含水量(SWC)和土壤容重(BD)呈负相关,与土壤粉粒(slit)和黏粒(clay)含量呈正相关,STP对土壤细颗粒的响应强度大于SOC和STN。研究区土壤化学计量在不同退耕恢复植被间差异显著,其中刺槐的土壤养分含量较其他植被类型更好,可为该地区植被恢复工作进一步开展提供参考。
郭鑫, 魏天兴, 陈宇轩, 沙国良, 任康, 于欢. 黄土丘陵区典型退耕恢复植被土壤生态化学计量特征[J]. 干旱区地理, 2022, 45(6): 1899-1907.
GUO Xin, WEI Tianxing, CHEN Yuxuan, SHA Guoliang, REN Kang, YU Huan. Characteristics of soil ecological stoichiometry in typical fallow-restored vegetation in the loess hilly areas[J]. Arid Land Geography, 2022, 45(6): 1899-1907.
表1
样地基本信息"
植物群落 | 海拔/m | 林龄/a | 平均高度/m | 平均胸径(基径)/cm | 郁闭度(盖度)/% | 林下主要植被 |
---|---|---|---|---|---|---|
油松(Pinus tabulaeformis) | 1363 | 20 | 7.3 | 8.9 | 61 | 毛莲蒿(Artemisia vestita) |
刺槐(Robinia pseudoacacia) | 1429 | 20 | 10.3 | 15.0 | 75 | 针茅(Stipa capillata)、赖草(Leymus secalinus)、紫苜蓿(Medicago sativa)、兴安胡枝子(Lespedeza daurica) |
沙棘(Hippophae rhamnoides) | 1390 | 20 | 1.8 | 3.5 | 70 | 赖草、茵陈蒿(Artemisia capillaris)、毛莲蒿、兴安胡枝子 |
草地 | 1377 | 20 | - | - | 85 | 兴安胡枝子、赖草、针茅 |
表2
不同植被土壤碳氮磷养分含量"
土壤指标 | 植物群落 | 最大值/g.kg-1 | 最小值/g.kg-1 | 平均值/g.kg-1 | 标准差 | 变异系数 |
---|---|---|---|---|---|---|
SOC | 油松 | 0.562 | 0.098 | 0.232 | 0.105 | 0.45 |
刺槐 | 0.947 | 0.219 | 0.367 | 0.183 | 0.50 | |
沙棘 | 0.992 | 0.087 | 0.302 | 0.243 | 0.80 | |
草地 | 0.764 | 0.172 | 0.341 | 0.179 | 0.52 | |
STN | 油松 | 0.055 | 0.020 | 0.034 | 0.009 | 0.26 |
刺槐 | 0.086 | 0.044 | 0.056 | 0.012 | 0.21 | |
沙棘 | 0.086 | 0.021 | 0.043 | 0.020 | 0.47 | |
草地 | 0.078 | 0.030 | 0.044 | 0.014 | 0.32 | |
STP | 油松 | 0.646 | 0.554 | 0.591 | 0.031 | 0.05 |
刺槐 | 0.656 | 0.565 | 0.619 | 0.027 | 0.04 | |
沙棘 | 0.596 | 0.493 | 0.557 | 0.025 | 0.04 | |
草地 | 0.689 | 0.588 | 0.631 | 0.026 | 0.04 |
表3
不同植被土壤化学计量比"
土壤指标 | 植物群落 | 最大值 | 最小值 | 平均值 | 标准差 | 变异系数 |
---|---|---|---|---|---|---|
C:N | 油松 | 10.163 | 3.449 | 6.746 | 1.959 | 0.29 |
刺槐 | 10.965 | 4.768 | 6.298 | 1.555 | 0.25 | |
沙棘 | 11.505 | 3.286 | 6.284 | 2.238 | 0.36 | |
草地 | 11.695 | 5.196 | 7.516 | 1.738 | 0.23 | |
C:P | 油松 | 0.969 | 0.170 | 0.395 | 0.181 | 0.46 |
刺槐 | 1.456 | 0.367 | 0.588 | 0.272 | 0.46 | |
沙棘 | 1.737 | 0.146 | 0.545 | 0.443 | 0.81 | |
草地 | 1.144 | 0.276 | 0.535 | 0.257 | 0.48 | |
N:P | 油松 | 0.095 | 0.035 | 0.058 | 0.016 | 0.28 |
刺槐 | 0.133 | 0.069 | 0.090 | 0.018 | 0.20 | |
沙棘 | 0.174 | 0.037 | 0.078 | 0.037 | 0.47 | |
草地 | 0.117 | 0.048 | 0.069 | 0.021 | 0.30 |
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