石林风景区不同石漠化人工修复方式对木本植物群落组成及种群生态位的影响

石漠化是我国西南喀斯特地区生态修复最严重的障碍,植被恢复是石漠化治理的重要途径。近50年来,我国开展了大量石漠化植被恢复的实践与研究,包括自然恢复与人工修复。但是,长期以来缺乏对已完成人工修复的植被的演替特征和修复效果的研究,而人工修复植被的效果评价能为石漠化生态修复提供理论依据与实践经验。以石林风景区中两类人工修复植被——栽植植被(PV)与飞播植被(ASV)为研究对象,以地带性自然植被(ZNV)为对照,研究人工修复植被中木本植物群落组成、群落多样性和种群生态位特征,以期揭示不同人工修复方式下的植被构成规律以及对有限资源的利用程度。结果表明:(1)在地带性自然植被、栽植植被和飞播植被3种植被类型中分别记录到木本植物92种(45科80属)、138种(50科101属)与44种(26科37属),3种植被类型中的共有种12种。(2)3种植被类型的Patrick丰富度指数与Shannon-Wiener多样性指数排序均呈现为地带性自然植被栽植植被飞播植被(P0.01),栽植植被与地带性自然植被之间的Jaccard相似性指数为0.14,飞播植被与地带性自然植被之间的Jaccard相似性指数为0.12;(3)3种植被类型中任意两者之间的生态位宽度均存在较大差异,但是清香木(Pistacia weinmannifolia)在3种植被类型中生态位宽度排位均靠前,利用资源能力较强;(4)生态位重叠程度的排序为地带性自然植被飞播植被栽植植被。综上,与地带性自然植被相比,人工修复植被物种多样性较低,但是人工修复植被的优势种中乡土植物占89.33%,乡土植物生态位较广,生态位重叠值偏低,植被较为稳定。在人工修复植被中,栽植植被的修复效果优于飞播植被。研究结果对未来喀斯特石漠化地区进行人工植被修复的物种规划与群落构建时具有重要的参考价值。

Effect of different artificial restoration methods of Karst rocky desertification on community composition and niche characteristics of woody populations in Shilin scenic area

Karst rocky desertification (KRD) is one of the biggest challenges in the ecological restoration of the karst region in Southwest China, and vegetation restoration is a crucial approach. In the past 50 years, domestic practices and researches have been carried out about natural and artificial restoration of KRD. However, little is known about the succession characteristics and restoration effects of the revegetation in the KRD area. Here we investigated the community diversity and niche characteristics of the Planted Vegetation (PV) and the Air Seeding Vegetation (ASV) in Shilin Scenic Area, Kunming, Yunnan, with Zonal Natural Vegetation (ZNV) selected as the comparison, to reveal the differences in the vegetation composition and the resource utilization characteristics between different artificial restoration methods. Results show that: (1) 92 species belonging to 80 genera of 45 families, 138 species belonging to 101 genera of 50 families and 44 species belonging to 37 genera of 26 families were recorded in ZNV, PV and ASV respectively. 12 common species were identified among three vegetation types. (2) The significant difference of Patrick index and Shannon-Wiener index were detected among three revegetation types, sequencing ZNV > PV > ASV (P<0.01). The Jaccard index between PV and ZNV was 0.14 and that between ASV and ZNV was 0.12. (3) The Niche width of species varied remarkably among ZNV, PV and ASV. Pistacia weinmannifolia was among the top species with higher niche width in all vegetation types, which meant it had a prominent competition ability in harsh circumstances. (4) The niche overlap showed ZNV > ASV > PV, indicating that the species diversity index in revegetation was smaller than that in zonal natural vegetation. However, 89.33% of the dominant species in the revegetation were indigenous species with broader niche width and smaller niche overlap, which demonstrated the stability of revegetation. Besides, PV had a more effective restoration effect compared with ASV. Our findings can provide insights for the plant community construction in the ecological restoration of KRD in Southwest China.