薛杨 梁居智 宿少锋 姚小兰 王小燕 林之盼 薛雁文

摘  要：濱海防护林及半自然次生林禁伐后的植被结构、土壤养分特征的变化，是认识林地演替生态过程和盐碱地生态恢复的核心内容，对生物多样性保护和生态系统服务功能提升具有重要意义。本研究针对海南岛北部低海拔滨海地区1994年开始禁伐的人工林与次生林，采用典型样地法，比较研究3类人工林（大叶相思林、木麻黄林、桉树林）和邻近的次生林、混交林（对照）等5个森林类型的植被与土壤养分特征。结果表明：（1）5种森林群落内主要植被共计34科54属57种，次生林和混交林群落物种组成较其他纯林物种丰富，木麻黄林内无灌木生长，除次生林外，其他森林类型草本层物种最丰富;（2）5种森林的土壤皆呈酸性，桉树林、次生林和混交林的土壤有机质和全氮含量较高，但土壤有效磷含量显著低于木麻黄林和大叶相思林（P<0.05）;（3）混交林土壤速效钾最高为11.27 mg/kg，其他森林类型均很低甚至未检出;（4）次生林土壤有机质含量、混交林土壤速效钾含量与群落物种组成呈正相关;土壤全氮含量与树龄、树高等呈正相关。因此，土壤养分随着禁伐时间增长而增加;桉树林具有较高的有机质和氮含量，但木麻黄林和大叶相思林的磷含量较高，次生混交林则有着较高的钾含量。

关键词：森林类型;植被特征;土壤养分;滨海台地中图分类号：S714      文献标识码：A

Changes of Vegetation and Soil Nutrient in Different Forests after Logging Banin Tropical Coastal Area of Hainan Island

Xue Yang¹， Liang Juzhi^1*， SU Shaofeng¹， Yao Xiaolan²， Wang Xiaoyan¹， Lin Zhipan¹， Xue Yanwen¹

1. Hainan Institute of Forestry Science， Haikou， Hainan 571100， China; 2. College of Ecology and Environment， Hainan University， Haikou， Hainan 570228， China

Abstract： The changes of vegetation structures and soil nutrients in coastal forests are important to understand the forest ecological process and restoration of saline-alkali land， and for the biodiversity conservation and ecosystem service function enhancement. The vegetation and soil nutrient characteristics of three types of plantations （Acacia auriculiformis，Casuarina equisetifoliaandEucalyptus robusta）， secondary forests and mixed forests （control） banned from cutting in low altitude coastal areas of northern Hainan Island in 1994 were studied using the typical plot method. 57 species belonging to 54 genera and 34 families were investigated. The species composition of the secondary forest and mixed forest communities was richer than that of the pure forest， and no shrubs grew in theC. equisetifolia plantation. In addition to the secondary forests， other forest types had the most abundant species in herblayer. The soil of the five forest plots was acidic， and the content of organic matter and total N in theEucalyptus robusta plantation， secondary forest and mixed forest was the highest， but the content of available P in theA. auriculiformisandC. equisetifolia plantation was significantly higher than that of the others （P<0.05）. Except the mixed forest， available K was 11.27 mg/kg， and that in the other forest types was very low or even undetected. There existed positive correlation between organic matter in the secondary forest， available K in the mixed forests and species compositions. There existed positive correlation in total nitrogen， tree age and height. Therefore， soil nutrients increased with the increase of cutting time. TheE. robustaforest had higher organic matter and nitrogen content， but theC. equisetifolia andA. auriculiformisforests had higher phosphorus content， while the secondary mixed forest had higher potassium content.

Keywords： forest type; vegetation characteristics; soil nutrients; coastal terrace

DOI： 10.3969/j.issn.1000-2561.2020.06.028

海防林和滨海台地人工林是抵御台风、减轻土壤盐碱化和保护农业生产等的一个重要手段，同时具有供应木材、维护生态平衡和提升生态功能等重要作用^[1]。但是，与自然半自然森林和内陆人工林相比，滨海人工林的植被结构和土壤成分研究较少;特别是这些人工林在禁伐后的植被演替、土壤养分变化规律等还缺乏系统性的实验研究^[2]。

海南省文昌市位于我国最大的热带岛屿海南岛东北部，是我国台风登陆最频繁、破坏最严重的地区之一。……