摘要
四川省江油市涪江中上游的珍稀植物距瓣尾囊草(Urophysa rochkii),大部分因其自然生境地将蓄水淹没正濒临灭绝。研究了地质地貌及水文、岩石风化物与根部残积物的矿物成分和养分等距瓣尾囊草独特生境特征,旨在为距瓣尾囊草的抢救与保护提供科学依据。结果表明,裂隙网络、糜棱岩化、偏酸性的孔隙水可减轻距瓣尾囊草岩隙着生的阻力;其生长期与降雨不同步,但着生岩壁的上层滞水和饱气带以及向下倾斜的岩层利于水外溢,可为其提供在富水性贫瘠的石灰岩上生长所必需的水分;孔隙水及残积母质中的钙含量(400～500g/kg)显著高于其他养分,并与对照地的钙含量(85.47g/kg)差异显著。可见,生长基质中较高的钙含量及持续的钙源可能是距瓣尾囊草迁地保护或活体培养过程中需重视的关键科学问题。要解释距瓣尾囊草喜钙性,还需进一步研究距瓣尾囊草适生的钙浓度阈值及其吸收、运转和利用的生理机制。
Urophysa rochkii a rare plant, mainly distributes in the upper and middle reaches of Fu- jiang river, Jiangyou, Sichuan. Unfortunately, the habitat of the plant has been submerged due to the construction of reservoirs. Therefore, in order to efficiently protect U. rochkii and its habitat, mine, the geological and hydrological properties, nutrition of weathering residue, local tempera- ture and precipitation of U. rockii habitat were investigated. Mylonitized rock zones, terrene cracks, low pH of groundwater and fissure water provide effective condition for the growth of U. rockii. The growth periods of U. rockii are not synchronal with precipitation, but the growth of U. rockii significantly related with water in fissure and aeration zone. The calcium contents （400 --500 g/kg） in interstitial water （i. e. fissure water and groundwater） and weathering residue are significantly higher than other nutrients and the calcium content of in comparison plot （85.47 g/ kg）. These results suggested that the relative higher content of calcium and continuous resource of calcium play important role in the growth of U. rockii. However, more work should be carried out in the mechanism of calcium absorption, calcium transportation and calcium using of U. rockii.
出处
《四川农业大学学报》
CSCD
北大核心
2011年第4期488-494,共7页
Journal of Sichuan Agricultural University
基金
四川省环保厅珍稀植物距瓣尾囊草生物生态学科学考察及抢救性移植方案编制
四川农业大学科技创新团队项目(No.00370501)
关键词
距瓣尾囊草
生境特征
泥盆纪石灰岩
钙依赖性
Urophysa rockii
habitat properties
Devonian limestone
calcium-dependent
