首页 | 官方网站   微博 | 高级检索  
     

铜尾矿自然定居白茅对体内氮磷的适时分配及叶片氮磷代谢调节酶活性动态
引用本文:沈章军,孙庆业,田胜尼.铜尾矿自然定居白茅对体内氮磷的适时分配及叶片氮磷代谢调节酶活性动态[J].植物生态学报,2012,36(2):159-168.
作者姓名:沈章军  孙庆业  田胜尼
作者单位:安徽大学资源与环境工程学院, 合肥 230039;
合肥师范学院生命科学系, 合肥 230061;
安徽农业大学生命科学学院, 合肥 230036
基金项目:国家环保公益性行业科研专项,安徽省高校省级优秀青年人才基金,安徽省高校自然科学研究项目
摘    要: 白茅(Imperata cylindrica)为铜尾矿废弃地的自然定居优势植物。以农田正常生长的白茅居群为对照, 通过对不同生长时期的白茅体内氮(N)、磷(P)营养浓度, 叶片硝酸还原酶和酸性磷酸酶活性变化等的研究, 探讨铜尾矿胁迫下白茅在营养利用上的生理适应特征。研究结果表明, 在不同的生长时期, 白茅各器官内N、P分配存在一定的差异。在萌芽期, 两居群白茅体内的N、P均主要集中于根状茎。在花蕾期、成熟期时, 两居群白茅体内的N、P均向成熟叶片中迁移, 叶片中N、P浓度均达到最高。但在衰败期时, 铜尾矿居群白茅体内的N主要迁移到根状茎中, P在根状茎中的浓度也达到生长期中的最高值, 而农田居群白茅成熟叶片内N、P浓度依然最高。铜尾矿白茅叶片N、P的再吸收效率分别为49.54%–65.22%和74.71%–98.71%, 而在农田系统中分别为18.18%–52.81%和71.39%–84.07%; 铜尾矿白茅衰老叶片中P达到完全再吸收的程度。铜尾矿白茅叶片硝酸还原酶活性在生长旺盛期显著高于农田居群(p < 0.05), 是白茅加强对自身氮养分代谢活动调节作用的表现; 同一生长时期白茅叶片酸性磷酸酶活性在两种生境间差异性并不明显(p > 0.05), 但随着生长期的延长, 白茅叶片酸性磷酸酶活性表现出不断升高的趋势, 这有利于生长后期衰老叶片中有机P的水解再吸收。可见, 铜尾矿中生长的白茅通过对N、P养分的适时分配, 提高营养成分的再吸收效率, 调节N、P代谢相关调节酶活性的变化方式来减轻铜尾矿生境的营养胁迫。

关 键 词:酸性磷酸酶  铜尾矿  白茅  硝酸还原酶    养分再吸收率  
收稿时间:2011-09-21
修稿时间:2011-11-14

Dynamics of nitrogen and phosphorus concentrations and nitrate reductase and acidic phosphatase activities in Imperata cylindrica on copper mine tailings
SHEN Zhang-Jun , SUN Qing-Ye , TIAN Sheng-Ni.Dynamics of nitrogen and phosphorus concentrations and nitrate reductase and acidic phosphatase activities in Imperata cylindrica on copper mine tailings[J].Acta Phytoecologica Sinica,2012,36(2):159-168.
Authors:SHEN Zhang-Jun  SUN Qing-Ye  TIAN Sheng-Ni
Affiliation:School of Resources and Environment Engineering, Anhui University, Hefei 230039, China;

School of Life Sciences, Hefei Normal University, Hefei 230061, China; and 3School of Life Sciences, Anhui Agricultural University, Hefei 230036, China
Abstract:Aims Our objective was to study self-regulation of nitrogen(N) and phosphorus(P) nutrient use by Imperata cylindrica at different growth stages on copper mine tailings.Methods We obtained samples from two different nutrient habitats:copper mine tailings and farmlands.We investigated N and P distributions,N∶ P,nutrient resorption rate,nitrate reductase and acidic phosphatase activi-ties in I.cylindrica organs.Important findings The N and P distributions in I.cylindrica differed by growth period.During the initial stage of growth,N and P in both populations were mainly in the rhizomes.At bud and mature times,N and P concentra-tions were highest in leaves and lowest in roots and rhizome.At the decay period,N and P concentrations in se-nescent leaves were(9.19 ± 0.80) and(0.05 ± 0.03) mg·g-1,respectively,which were significantly lower than for the control farmland.The N and P resorption efficiencies of I.cylindrica leaves in the tailings were 49.54%-65.22% and 74.71%-98.71%,respectively,with P in senescent leaves resorbed completely.However,values for the farmland system were 18.18%-52.81% and 71.39%-84.07%,respectively.These results indicated that the poor nutrition condition of the tailings can increase I.cylindrica nutrient resorption efficiency.Nitrate re-ductase activity of I.cylindrica leaves in the tailings was significantly higher than in the farmlands(p < 0.05) ;this is useful to regulate I.cylindrica nitrogen metabolism activities.But with plant growth,the differences gradually disappeared.At the same growth period,acidic phosphatase activity of I.cylindrica leaves between the tailings and the farmlands were not significantly significant(p > 0.05) .With plant growth,the acidic phosphatase activi-ties increased,which was conducive to decompose organophosphate in senescent leaves and increase P resorptionefficiencies.
Keywords:acidic phosphatase  copper tailings  Imperata cylindrica  nitrate reductase  nitrogen  nutrient resorption  phosphorus
本文献已被 CNKI 万方数据 等数据库收录!
点击此处可从《植物生态学报》浏览原始摘要信息
点击此处可从《植物生态学报》下载免费的PDF全文
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号