川西林盘植物群落结构历史变化特征分析——以成都市郫都区为例

林盘是川西平原地区一种极具特色的传统农村聚落形态,具有突出的农业文化遗产价值。植被是构成林盘的核心要素,了解植物群落的历史变化过程可以为传统林盘的保护工作提供科学依据。本研究首先通过查阅历史资料掌握传统林盘植物群落的结构特征,然后选取成都市郫都区4个林盘样地和3个灌渠边林地进行植物群落调查,从而比较不同时期林盘植物群落结构。调查结果显示,目前林盘植物群落结构发生的主要变化包括乔木层中的传统优势种杉木、楠木及柏树被黑壳楠取代,林盘植被趋向单一化;竹类的物种丰富度下降明显,竹林退化严重;灌渠林地中桤木及柏树被枫杨和构树取代,竹类基本消失。川西平原地区社会和经济的变迁破坏了传统农业系统中人口、耕地和林盘之间的平衡,从而导致了林盘植被群落结构的改变。

Historical Changes of Plant Community Structure and Biodiversity of Linpan: A Case Study in Pi County of Chengdu

Linpan is a traditional rural settlement unit with distinctive characteristics and outstanding agricultural heritage conservation values in Chengdu plain. Plant is the key component of Linpan system and the study on historical change features of plant community can provide a scientific guidance for conservation efforts of Linpan in the study area. First, we analyzed the historical plant community structures by referring to historical data. Then a plant community investigation of 4 representative Linpan plots and 3 wood land plots along irrigation ditch was conducted in Pi County, Chengdu. Finally, we compared the plant community structures in different periods. The main changes of Linpan plant community include: Phoebe zhennan, Cunninghamia lanceolata and Platycladus orientalis were the dominant species in traditional Linpan, but now they have been replaced by Lindera megaphylla. An obvious degradation of bamboo forest could be observed in the study region. The species used to be prevalent in the wood land along irrigation ditch were Alnus cremastogyne and Platycladus orientalis, however these species have been replaced by Pterocarya stenoptera and Broussonetia papyrifera. Bamboo is not observed in the wood land along irrigation ditch. The social and economic changes in Pi County break the relationship between population, farm land and Lipan and ultimately result in the plant community changes.