本文選題：軟性狀　切入點(diǎn)：氣體交換　出處：《植物學(xué)報(bào)》2017年03期 　論文類型：期刊論文

【摘要】：放牧是草地主要利用方式之一,不同季節(jié)放牧通過影響草地功能性狀間的權(quán)衡從而影響牧后再生及補(bǔ)償性生長。通過測定內(nèi)蒙古溫帶草原優(yōu)勢種羊草(Leymus chinensis)的株高、節(jié)間距和分蘗數(shù)等軟性狀及氣體交換、抗氧化酶系統(tǒng)和根莖葉滲透調(diào)節(jié)物質(zhì)的含量等硬性狀,分析了不同季節(jié)放牧處理下羊草功能性狀的變化及其權(quán)衡關(guān)系。結(jié)果表明,3年短期放牧處理下,類連續(xù)放牧(T1)比春季放牧樣地(T2)羊草表現(xiàn)出更強(qiáng)的避牧性與耐牧性。類連續(xù)放牧與春季放牧樣地羊草軟性狀及光合特性表現(xiàn)出一致性,6月放牧干擾降低了羊草的凈光合速率(P_n),8月放牧干擾通過增加電子傳遞速率(ETR)及光系統(tǒng)Ⅱ(PSⅡ)分配于光化學(xué)反應(yīng)(P)的比值等增大P_n。但春季放牧樣地羊草株高較高,且光合產(chǎn)物較多分配于葉片,導(dǎo)致大量有機(jī)物質(zhì)被啃食,不利于牧草再生。而類連續(xù)放牧羊草將較多的有機(jī)物質(zhì)分配于根莖,有利于牧草根系吸水及牧后再生。因此,3年短期放牧處理下,類連續(xù)放牧更有利于牧草再生及草原的可持續(xù)利用。
[Abstract]:Grazing is one of the main ways of grassland utilization. Grazing in different seasons affects regeneration and compensatory growth after grazing by affecting the trade-offs between functional traits of grassland. The plant height of Leymus chinensis, a dominant cultivator in temperate grassland of Inner Mongolia, was determined. Soft characters, such as pitch of nodes and number of tillers, gas exchange, antioxidant enzyme system and content of osmotic regulator in rhizome and leaf, etc. The changes of functional traits of Leymus chinensis under different season grazing treatments and their trade-offs were analyzed. Compared with spring grazing plots, Leymus chinensis showed stronger grazing avoidance and tolerance. The soft characters and photosynthetic characteristics of Leymus chinensis were consistent with those of spring grazing land. In June, grazing disturbance decreased the grazing ability of Leymus chinensis. In August, the ratio of grazing disturbance to photochemical reaction (P) was increased by increasing electron transfer rate (ETR) and photochemical reaction (PS 鈪，

本文編號：1626450