川西地区蜜桔林不同遮荫度对3种禾草生物特性和地上生物量的作用  

The Effects of Different Shading Degrees of Orange Stand on three Herbages' biological characteristics and Aboveground Biomass in West of Sichuan

作　　者：唐天云[1] 胡庭兴[1] 陈光升[1] 罗龙海[1] 武卫国[1] 刘闯[1] 

机构地区：[1]四川农业大学四川省林业生态工程重点实验室,四川雅安625014

出　　处：《草业科学》2008年第8期40-45,共6页Pratacultural Science

基　　金：国家科技部"十一五"科技支撑计划(2006BAC01A11);四川省重点学科建设项目(SZD0419)

摘　　要：通过对蜜桔林5个遮荫度(0,27%,50%,65%和70%)下3种禾草(扁穗牛鞭草Hemarthria compressal、高羊茅Festuca arundinecea和鸭茅Dactylis glomerata)的叶绿素含量、光合速率和地上生物量研究,结果表明,1)在林-草复合农林模式中,扁穗牛鞭草在全光照和低遮荫度(<27%)下有最大的地上生物量,并随遮荫度的增加,其光合速率与地上生物量逐渐降低;2)高羊茅在中遮荫度(50%左右)下,有最大叶绿素总量(1.80 mg/g)和最大地上生物量,在低遮荫度和高遮荫度的处理下,其叶绿素总量和地上生物量都较低;3)鸭茅在中、高遮荫度下有最大的叶绿素b含量和最大地上生物量;4)3种禾草的光合速率都是在全光照下最大,随着遮荫度的增加,光合速率下降的程度不同。总之,3种禾草的耐荫性顺序是:扁穗牛鞭草<高羊茅<鸭茅,因此,在构建林-草复合种植模式过程中,应根据林木的覆盖度(遮荫度)来确定适宜种植的牧草。The chlorophyll content, photosynthesis rates and aboveground biomass of three grasses （ Hemarthria compressa, Festuca arundinecea and Dactylis glomerata ） in different shading degrees （0, 27%, 50%, 65% and 70%） under Chinese honey orange stand were studied. The results showed that 1） Under lower shade degree （0% to 27%）, H. compressa performed the greatest photosynthetic rate and the largest aboveground biomass, with the increase of shade, the photosynthetic rate and its aboveground biomass decreased gradually; 2） Under shade degrees of 50%, F. arundinecea showed the largest total chlorophyll （1.80 mg/g） content and the largest aboveground biomass, and its total chlorophyll biomass is low under the low and high degree of shading treatment; 3） Under the high shade degree, D. glomerata showed the largest chlorophyll b content and aboveground biomass; 4） The photosynthetic rates of three grasses were the highest without shading, and with the increase of shading degree, it decreased at different levels. The order of shade-tolerant ability of three grasses was H. compressal〈 F. arundinecea 〈 D. glomerata.

关 键 词：遮荫度 地上生物量 光合速率 叶绿素 禾草 

分 类 号：S54[农业科学—作物学]