| 摘要: |
| 为探究森林火烧迹地中的植物多样性和土壤理化性质的变化规律, 试验选取广东西江烂柯
山省级自然保护区和肇庆市国有北岭山林场内不同火烧恢复年限 ( 2. 5 ~ 16. 0
过的森林公园 (对照样地) 样地进行调查和研究, 详细记录样方内林下植物种
年
类
)
名
的
称
样地和未被火烧
、 数量和覆盖度
等, 并计算植物多样性指数。 同时, 测定了表层土壤 (0 ~ 10 cm) 的理化性质, 大团聚体湿筛和微团
聚体粒径质量分布。 结果表明, (1) 火烧后, 林下植物种类、 数量, Margalef 丰富度指数和 ShannonWiener 指数都低于对照样地。 火烧后的样地林下植被种类、 数量、 Shannon-Wiener 指数、 Pielou 均匀
度指数和枯落物厚度随恢复时间变长总体表现出先增加后减少的趋势。 而 Margalef 丰富度指数和 Fisher′s α 指数都呈现总体增加的趋势; 所测的对植物生长有主要影响的土壤理化性质多与植物的 Simpson
优势度指数和生境 Fisher′s α 指数呈正相关, 而与其他多样性指数负相关。 (2) 随着火烧样地恢复年限
的增加, 土壤 pH 值、 全钾、 全磷和有效磷含量都总体上呈现出先升高再下降的趋势, 而速效钾、 全
氮、 水解氮含量、 阳离子交换量都呈现先降低后升高的趋势。 (3) 随着火烧后恢复年限的增加, 湿筛
后土壤水稳性大团聚体粒径>0. 50 mm 和≤0. 25 mm 粒径百分比呈现出先升高后下降的趋势, 火烧有
助于短期提高表层土壤的大团聚体含量和稳定性。 火烧后微团聚体≤0. 25 mm 的 5 个粒径级别, 其百
分比随恢复时间的延长都有先降低后升高的趋势, 火烧后短期的生态恢复增强了微团聚体的稳定性和
抗侵蚀能力。 |
| 关键词: 火烧恢复 生物多样性 森林 土壤理化性质 水稳性大团聚体 微团聚体 |
| DOI： |
| 分类号: |
| 基金项目: |
|
| The Pattern of Understory Plant Diversity and Soil Physicochemical Properties in the Severely Burned Areas of Forests |
|
Wang Minghuai,Cui Fangke,WU Zepeng,Xu XiuYu,Ou Shikun,Chen Jinghuan,Ma ShengJie,Cai ZhiQuan
|
|
1.Guangdong Academy of Forestry;2.Horticulture Department of Foshan University;3.LanKeshan Provincial Nature Reserve in Xijiang Guangdong;4.Foshan University
|
| Abstract: |
| To investigate the changes in plant biodiversity and soil physicochemical properties in severel
burned forest area
y
s, we selected sample plots from different recovery periods (2. 5-16. 0 years) after intense
burning in Lankeshan Provincial Nature Reserve in Xijiang, Guangdong and Beiling Mountain forest farms, as
well as plots from a forest park that had never been burned (control group). We recorded detailed information
on plant species, their numbers, and coverage within the sample plots, and calculated plant diversity indices.
Concurrently, we measured the physicochemical properties of the topsoil (0-10 cm) and the particle size distribution of macroaggregates (wet sieving) and micro-aggregates. The results showed that, (1) After severe
burning, the number of understory plant species, their abundance, Margalef richness index, and Shannon -
Wiener diversity index were all lower than those in the control plots that had not been burned. The understory
plant species and abundance significantly decreased after burning. Over time, the burned plots showed an initial
increase followed by a decrease in the number of understory plant species, Shannon - Wiener index, Pielou
evenness index, and litter depth. However, Margalef richness index and Fisher′s α showed an overall increasing trend. Most soil physicochemical properties were positively correlated with Simpson dominance index and
habitat Fisher′s α but negatively correlated with other diversity indices; however, these correlations were not
significant. (2) With an increase in the recovery period after burning, soil pH, total potassium, total phosphorus, and available phosphorus generally first increased and then decreased. Meanwhile, available potassium, total nitrogen, hydrolyzable nitrogen, cation exchange capacity showed an initial decrease followed by an
increase. (3) As the recovery period after burning increased, the content of stable macroaggregates ( >0. 50
mm and >0. 25 mm) in the soil increased initially and then decreased. Severe burning helped increase the content of macroaggregates and soil stability in the short term. The content of micro-aggregates (≤0. 25 mm) decreased initially and then increased with the lengthening of recovery time. The short-term recovery process after
burning enhanced the erosion-resistant stability of fine soil particles. |
| Key words: fire recovery biodiversity forest soil physico-chemical properties water stable macroaggregates micro-aggregates |
