本文選題：化感作用　切入點(diǎn)：連栽障礙　出處：《生態(tài)學(xué)報(bào)》2017年12期 　論文類型：期刊論文

【摘要】：選取10—40a不同代際的長(zhǎng)期集約連栽楊樹土壤為對(duì)象,從自毒作用的角度探討人工林連栽障礙的原因與機(jī)理。實(shí)施了不同連栽代際的楊樹人工林土壤對(duì)萵苣種子發(fā)芽和扦插楊樹枝條生長(zhǎng)的抑制活性的系統(tǒng)生物測(cè)定試驗(yàn)。結(jié)果表明,連栽楊樹林的根際土壤比非根際土壤能夠顯著抑制萵苣種子萌發(fā)率。對(duì)Ⅰ、Ⅱ、Ⅲ代林根際土壤的濃度梯度試驗(yàn)都表明浸提液的質(zhì)量濃度越大,對(duì)種子萌發(fā)的抑制性越強(qiáng),其中Ⅲ代林處理液的濃度效應(yīng)最明顯。將Ⅰ、Ⅱ、Ⅲ代楊樹林根際土壤配置成加營(yíng)養(yǎng)液組與無(wú)營(yíng)養(yǎng)液組兩組對(duì)照水培溶液測(cè)定扦插楊樹枝條的胚芽生長(zhǎng)長(zhǎng)度和根伸長(zhǎng)長(zhǎng)度。結(jié)果表明,III代林根際土壤處理液的胚芽生長(zhǎng)長(zhǎng)度和根伸長(zhǎng)長(zhǎng)度顯著小于Ⅱ代林根際土壤處理液,Ⅱ代林處理又顯著小于Ⅰ代林處理,Ⅰ代林處理液與對(duì)照組無(wú)顯著差別,這種隨林代增大、根際土壤對(duì)植株生長(zhǎng)的抑制活性增大的趨勢(shì)在加營(yíng)養(yǎng)液組更為顯著。本文確定了連栽土壤抑制活性的根際效應(yīng)與濃度效應(yīng),為連栽楊樹人工林的自毒作用研究提供了重要的實(shí)驗(yàn)依據(jù),并推斷連栽楊樹人工林通過(guò)根系分泌物的方式在根際部分逐代積累自毒物質(zhì),由于自毒物質(zhì)的濃度效應(yīng),Ⅰ代林階段自毒效應(yīng)不顯著甚至促進(jìn)林木生長(zhǎng);隨著集約時(shí)間增長(zhǎng),到Ⅲ代林階段自毒效應(yīng)顯著抑制楊樹生長(zhǎng)和更新。在集約撫育中,對(duì)土壤實(shí)施人工添加營(yíng)養(yǎng)液的方式無(wú)法緩解其抑制性自毒作用,有可能加劇連栽障礙的產(chǎn)生。
[Abstract]:The soil of long-term intensive poplar planting in 10-40a with different generations was selected as the object. From the perspective of autotoxicity, the reason and mechanism of continuous planting obstacle in artificial forest were discussed. The systematic bioassay test of the inhibition activity of different intergenerational poplar plantation soil on lettuce seed germination and cuttage poplar branch growth was carried out. The seed germination rate of lettuce was significantly inhibited by the rhizosphere soil of poplar forest with continuous planting, and the concentration gradient test of rhizosphere soil of generations 鈪，

本文編號(hào)：1608768