摘要
在小尺度范围内,地形差异导致的环境异质性是物种格局形成和演变的环境基础。在2009年7—8月野外调查的基础上,借助GIS和S-PLUS软件,利用广义相加模型(GAM)定量分析了黑河上游祁连山北坡天然草地亚洲小车蝗多度与海拔、坡向、坡度和剖面曲率等地形因子之间的关系。结果表明:亚洲小车蝗具有较好的模型结构和模拟效果,能够较好地反映亚洲小车蝗的多度分布状况;各地形因子对亚洲小车蝗多度分布的影响不尽相同,其中海拔和剖面曲率起主导控制作用;在海拔梯度上,亚洲小车蝗多度随海拔的升高大体呈现倒"V"型变化趋势,在2380～2560m,多度与海拔呈正相关,海拔升至2560m以上时多度开始降低,与海拔呈负相关;亚洲小车蝗多度主要集中分布在剖面曲率<0的区域,在剖面曲率<-1.6的区域,多度与剖面曲率呈正相关,在剖面曲率>-1.6的区域,二者呈负相关。亚洲小车蝗多度与地形因子之间的相互关系及分布状态,反映了地形因子对水热条件的重分配,使亚洲小车蝗空间分布格局出现异质化。
The micro-scale environmental heterogeneity caused by topographical diversity is an environmental foundation underlying the formation and evolution of bio-geographic pattern. Based on the field survey in July-August 2009, and with the help of GIS and S-PLUS software, a quan- titative analysis with generalized additive model （GAM） was made on the relationships between the Oedaleus asiaticus abundance and topographical factors such as altitude, aspect, slope, and profile curvature in the natural grassland on northern slope of Qilian Mountains, the upper rea- ches of Heihe River. The model for O. asiaticus performed well, and could actually reflect the spatial distribution of O. asiaticus abundance. Different topographical factors had different effects on the spatial distribution of O. asiaticus abundance, among which, elevation and profile curva- ture showed dominant effects. With the increase of elevation, the O. asiaticus abundance showed a more or less reverse ＂V＂ trend. The abundance had a positive correlation with increasing alti- tude at altitude 2380-2560 m, but a negative correlation with the increasing altitude at altitude 〉2560 m. The O. asiaticus was mainly distributed in the regions with a profile curvature 〈0. There existed a positive correlation between the abundance and profile curvature when the profile curvature was 〈-1.6, and a negative correlation when the profile curvature was 〉-1.6. The relationships between the abundance of O. asiaticus and topographical factors as well as the spatial distribution pattern of O. asiaticus abundance indicated that the redistribution of water and heat conditions due to topographical factors caused the heterogeneity of the spatial distribution pattern of 0. asiaticus.
出处
《生态学杂志》
CAS
CSCD
北大核心
2013年第2期305-310,共6页
Chinese Journal of Ecology
基金
国家自然科学基金项目(91125014和40971039)
甘肃省科技支撑计划项目(1011FKCA157)
甘肃省生态经济重点学科项目资助
关键词
亚洲小车蝗
广义相加模型
多度
地形因子
空间格局
祁连山
Key words： Oedaleus asiaticus
generalized additive model （GAM）
abundance
topographicalfactor
spatial pattern
Qilian Mountains.
