高寒山区混播草地燕麦和毛苕子生物量分配格局对组分密度比的响应

生态学杂志

高寒山区混播草地燕麦和毛苕子生物量分配格局对组分密度比的响应

张静,赵成章^**

(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)

出版日期:2013-02-10 发布日期:2013-02-10

Distribution patterns of the biomass of Avena sativa and Vicia villosa in response to the component density ratio of the grass species in a mixedseeding grassland in alpine region of Qilian Mountains, Northwest China.

ZHANG Jing, ZHAO Cheng-zhang^**

(Research Center of Wetland Resources Protection and Industrial Development Engineering of Gansu Province, College of Geography and Environment Science, Northwest Normal University, Lanzhou 730070, China)

Online:2013-02-10 Published:2013-02-10

摘要/Abstract

摘要：

密度梯度对植物生物量分配格局的制约影响到混播草地在生态和生产上表现。2010年6—9月采用取代系列实验方法，在石羊河上游建立1年生人工混播草地，按燕麦(Avena sativa L.)与毛苕子(Vicia villosa Roth)的密度比例设置A(8∶2)、B(6∶4)、C(5∶5)、D(4∶6)和E(2∶8) 5个处理，研究了密度对燕麦与毛苕子生物量分配格局的影响。结果表明：混播草地中随着燕麦相对密度的减小和毛苕子相对密度的增大，燕麦根系生物量先减小后增大最后再减小的趋势与毛苕子相反，燕麦和毛苕子茎、叶生物量先减小后增大；随着牧草的生长，5种混播草地中燕麦和毛苕子茎生物量分配比例逐渐增加，叶、根生物量分配比例逐渐减少。密度制约下混播牧草资源分配策略发生的调整，证明了植物地上部分对光竞争的不对称性和地下部分对资源竞争的对称性，毛苕子攀援生长及其对燕麦茎秆的压力使植物茎秆生物量分配比例较高，实现了资源利用的最大化。

Abstract: Plant density gradient can restrict the distribution pattern of plant biomass, and thus, affect the performances of mixedseeding grassland in ecology and production. From June to September 2010, a replacement series experiment was conducted to establish a piece of grassland with mixedseeding of Avena sativa and Vicia villosa in the upper reaches of Shiyang River, Gansu Province of Northwest China. Five treatments were installed, according to the relative density of A. sativa to V. villosa, i.e., 8∶2, 6∶4, 5∶5, 4∶6, and 2∶8, with the effects of the density gradient on the distribution patterns of the biomass of A. sativa and V. vilosa studied. With the decreasing relative density of A. sativa and the increasing relative density of V. villosa, the root-biomass of A. sativa decreased first and increased then, and decreased lastly, while that of V. villosa was in the contrary. The stem and leaf biomass of A. sativa and V. villosa increased after an initial decrease. With the growth of the grasses, the allocation ratio of the stem biomass of A. sativa and V. vilosa in the five treatments increased gradually, while that of the leaf and root biomass was in adverse. The adjustment of the resource allocation strategies of the mixedseeding grasses under the restriction of plant density gradient demonstrated the asymmetry of the light competition of plant aboveground parts and the symmetry of the resource competition of underground parts. The climbing growth of V. vilosa and its pressure on A. sativa stem made the plants have higher allocation ratio of stem biomass, and achieve the maximum resource use.

Key words: Root cutting, Photosynthetic rate, Aboveground biomass, Water use efficiency (WUE), Maize

张静,赵成章**. 高寒山区混播草地燕麦和毛苕子生物量分配格局对组分密度比的响应[J]. 生态学杂志.

ZHANG Jing, ZHAO Cheng-zhang**. Distribution patterns of the biomass of Avena sativa and Vicia villosa in response to the component density ratio of the grass species in a mixedseeding grassland in alpine region of Qilian Mountains, Northwest China.[J]. cje.