高寒草地甘肃臭草斑块不同发育阶段茎-叶生物量分配:异速生长分析  

Biomass allocation of stems and leaves in Melica przewalskyi under different developmental stages in alpine grassland: Allometric scaling analysis

作　　者：党晶晶[1] 赵成章[1] 王继伟[1] 

机构地区：[1]西北师范大学地理与环境科学学院甘肃省湿地资源保护与产业发展工程研究中心,兰州730070

出　　处：《生态学杂志》2015年第6期1540-1545,共6页Chinese Journal of Ecology

基　　金：国家自然科学基金项目(91125014;40971039);甘肃省科技支撑计划项目(1011FKCA157);甘肃省生态学重点学科项目资助

摘　　要：植物生物量分配格局反映了环境对植物的选择和植物对环境的响应。在祁连山高寒退化草地,采用标准化主轴估计(standardized major axis estimation)方法,探讨甘肃臭草(Melica przewalskyi)茎、叶生物量变化及其分配策略对斑块不同发育阶段(斑块形成、斑块扩散、斑块稳定及斑块衰退阶段)的响应。结果表明:随着甘肃臭草斑块的发育,甘肃臭草茎生物量积累呈先上升后下降趋势,茎生物量分配比例呈先下降后上升趋势;叶生物量积累及生物量分配比例在斑块形成、斑块扩散及斑块稳定阶段均呈逐渐上升趋势,斑块衰退阶段呈下降趋势;斑块形成阶段甘肃臭草茎叶生物量呈等速生长模式,斑块扩散及稳定阶段叶生物量的增长速度大于茎生物量的增长速度,斑块衰退阶段转为茎生物量的增长速度大于叶生物量的增长速度。随着斑块的发育,甘肃臭草由依靠增加叶干物质投入占领资源,转为减小叶生物量投入、提高茎生物量的增长速度。Plant biomass allocation pattern reflects the environmental selection to plant and plant adaptation to heterogeneous environment. In this study,the method of standardized major axis estimation was adopted to study the effects of different developmental stages of patch（ formation,diffusion,stability and recession） on stem and leaf biomass allocations of Melica przewalskyi in an alpine grassland of Qilian Mountain. The results showed that in the process of patch development,stem biomass accumulation increased firstly then decreased while the change of stem biomass allocation was on the contrary. Both leaf biomass accumulation and biomass allocation increased in stages of patch formation,patch diffusion and patch stability while decreased in the stage of patch recession. Isometric relationship between stem mass and leaf mass was found in patch formation stage,but allometric relationship was found in the other three stages. The growth speed of leaf mass was greater than that of stem mass at patch diffusion and patch stability stages,but the growth speed of stem mass was greater than that of leaf mass in patch recession stage. Overall,this study demonstrates the significant effect of disturbance on the growth of M. przewalskyi. Biomass allocation of stems and leaves in M. przewalskyi at different development stages showed that the reduction in leaf mass is faster than that of stem mass with the process of patch development.

关 键 词：甘肃臭草 斑块 茎干重 叶干重 生物量分配 异速增长 

分 类 号：Q945[生物学—植物学]