摘要
我国西南喀斯特生态环境在近50年中发生了巨大变化,森林覆盖率大幅度下降,土地质量退化,石漠化严重。近几年,我国西南已进行了有效的喀斯特生态环境治理,并取得了显著成效,但石漠化严重发展的势头并没有受到明显抑制。云南省石林风景区乃古景区主要有自然灌丛、次生柏树、原生草地、次生草地和裸露红土地等5种不同植被覆盖生态系统样块地。在该地按不同土壤深度采样,分析了土壤含根量,土壤生物的群落构成,进行了土壤生物多样性指标计算。研究样块地共采集到土壤动物标本5门10纲28目(类)共935头,表明该区土壤动物生物量较同纬度森林生态系统小,并且以蜱螨目、弹尾目、线虫目、鞘翅目和后孔寡毛目为优势类群,线蚓目、蜘蛛目、鳞翅目、双翅目为常见类群。土壤生物多样性指数在1 5以下,并随植被退化而急剧降低至裸露地的0 11。派盾螨科在石林景区各种环境下均有较多分布,是本灰岩红壤地区的适生类群。螨类中的礼服甲螨科和士革螨科对生态系统退化十分敏感;而螨类 弹尾类总个体数比值>1 5,与同纬度森林生态系统中<0 55有根本不同。喀斯特区域的生物量(个体密度)和类群数都大大低于同纬度低海拔非喀斯特区森林生态系统下。说明喀斯特景观在土壤动物多样性角度上的脆弱性。
The distribution and diversity of soil fauna in a sequence of ecosystem degradation in the Shilin National Park, Yunnan, China, has been preliminary studied. The degraded ecologic system includes the 5 type of vegetation covers: 1) natural bush; 2) planted cypress forest; 3)natural grass; 4)secondary grass; 5) bared red earth. A quadrate of 1m×1m in each eco-tessera was sampled for soil fauna collection. The animals were obtained either by picking up or by heat-removing respectively. The soil fauna were dominated by acarina, collembola, nematode,coleoptera,and opistopora in these soils. However, enchytraeidae, araneida, lepidoptera and diptera were also common groups. The diversity index H turned to be less than 1.5, drastically decreasing with the vegetation degradation trend. In the karst soils, parholaspidae was one of the most populated among the mites. The biomass of trhypochthoniidae and ologamasidae was very concentrated in the natural bush ecosystem, showing high sensitivity of mites to vegetation degradation. The biomass ratio of acarina to collembola in the studied soils ranged from 0.70 to 1.50, which was in great discrepancy to the results reported of the natural soils at similar latitude. The small soil fauna biomass and less diversity indicated that the studied soil was in a state of deterioration of soil fauna habitats and, in turn, the soil ecosystem health. The results also evidenced that the soil fauna were closely related to organic matters (such as the roots) in the karst soil was definitely vulnerable as regarded to the sustainable development of the Shilin Park.
出处
《资源科学》
CSSCI
CSCD
北大核心
2004年第z1期98-103,共6页
Resources Science
基金
国家自然科学基金委
中国西部生态环境重大研究计划项目"西南喀斯特生态系统与土壤生物区系响应"(编号90202017)
石林研究基金项目"不同植被下土壤有机碳的活泼性及其对土下溶蚀的影响"(编号200101)。
关键词
石林
喀斯特土壤
动物多样性
植被条件
生态系统退化
Stone Forest
Karst soils
Fauna diversity
Vegetation cover
Ecosystem degradation
作者简介
向昌国(1964～),男,湖南张家界人,副教授,从事土壤生物研究.通讯作者:宋林华,E-mail:Songlh@igsnrr.as.cn.
