摘要
测定了中国东北森林 -草原样带草原区 15个常见植物种叶片的 δ1 3 C值 ,并以此作为植物长期水分利用效率的指示值 ,研究了不同植物种的水分利用效率对年均降水量、年均大气温度和海拔高度等环境梯度变化的响应。结果表明 :有相当一部分植物种的 δ1 3 C值和水分利用效率均随年均降水量和年均温增加而呈不同程度的降低趋势(如羊草 (L eymus chinensis(Trin.) Tzvel.)、家榆 (Ulmuspumila L.)、小叶锦鸡儿 (Caragana microphylla L am.)、直立黄芪 (Astragalus adsurgens Pall.)、地榆 (Sanguisorba officinalis L.)和菊叶委陵菜 (Potentila tanacetifolia Willd.ex Schlecht.)等 ) ,随海拔高度增高而呈不同程度的增加趋势 (如扁蓿豆 (Melissitus ruthenicus(L.) Peschkova)、羊草、家榆、小叶锦鸡儿、直立黄芪、地榆等 ) ;而少数几个种 (如达乌里胡枝子 (L espedeza davurica(L axm.)Schindl.) ,麻花头 (Serratula centauroides L.)等 )则与大多数种的情况截然相反 ,另外部分植物种则随环境因子变化不大 (达乌里黄芪 (Astragalus dahuricus(Pall.) DC.)、中间锦鸡儿 (Caragana intermedia Kuang et H.C.Fu)和狭叶锦鸡儿 (Caragana stenophylla Pojark.) ,冷蒿 (Artemisia frigida Willd.)、糙叶黄芪
Leaf δ 13 C values were measured in fifteen plant species along the grassland zone of the Northeast China Transect (NECT). The responses of δ 13 C values and long term water use efficiency (WUE) as indicated by δ 13 C value of these species to environmental factors (annual average precipitation, annual average air temperature and altitude) were investigated. The δ 13 C value and WUE of many plant species decreased with increasing annual average precipitation and air temperature. Examples of such species include: Leymus chinensis (Trin.) Tzvel., Ulmus pumila L., Caragana microphylla Lam., Astragalus adsurgens Pall., Sanguisorba officinalis L. and Potentila tanacetifolia Willd. ex Schlecht. Other species show an increase in δ 13 C and WUE with increasing altitude ( Melissitus ruthenicus (L.) Peschkova, Leymus chinensis (Trin.) Tzvel., Ulmus pumila L., Caragana microphylla Lam., Astragalus adsurgens Pall. and Sanguisorba officinalis L., for instance).By contrast, a few plant species (Lespedeza davurica (Laxm.) Schindl. and Serratula centauroides L.) showed an opposite trend. Finally several species showed no change in δ 13 C value or WUE with these environmental factors (e.g. Astragalus dahuricus (Pall.) DC., Caragana intermedia Kuang et H. C. Fu, Caragana stenophylla Pojark., Artemisia frigida Willd., Astragalus scaberrimus Bunge, Glycyrrhiza uralensis Fisch.). These results demonstrate strong differences in the responses of water use status to environmental gradients among different plant species and that each species has its own adaptive strategy to environmental change. When considering restoration of degraded grasslands it is important to consider variation between plant species in their potential to adapt to dry habitats.
出处
《植物生态学报》
CAS
CSCD
北大核心
2000年第6期648-655,共8页
Chinese Journal of Plant Ecology
基金
国家重大基础研究项目!(G19990 4340 7)
国家自然科学基金重点项目!(39730 110 )
关键词
中国东北样带
Δ^13C
水分利用效率
气温
草原区
Northeast China Transect
δ
13 C value
Water use efficiency
Precipitation
Air temperature
Altitude
