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人类活动导致的气候变暖和农业面源污染已被认为是影响湿地植物生长和繁殖的重要因素.为了预测和缓解这些人类活动的影响,研究沼泽植物如何响应这些环境变化具有重要意义.本研究选取在欧亚大陆广泛分布的莎草科球茎植物扁秆藨草(Bolboschoenus planiculmis)为研究对象,考察气温变化(恒温:15、20、25℃及交替温度:20/10和30/15℃)和钾添加(0、1、3、9和18 mmol/L)对其生长和繁殖性状的影响.研究结果表明,高的恒温(20、25℃)比高的交替温度(30/15℃)更有利于扁秆藨草球茎的形成,而地上生物量和株高一般在较高温度下(30/15、25℃)达到最大值.扁秆藨草的繁殖和生长性状均与施钾量呈驼峰型关系,最适施钾量在1-3 mmol/L K.高恒温效应和最适钾浓度的交互作用对繁殖性状的促进作用最大,但是,较高的温度(30/15和25℃)和0-9mmol/L的钾浓度只促进了生长性状的生长.综上所述,扁秆藨草的种群优势度可能受益于全球变暖和额外的钾添加.“,”Aims Climate warming and agricultural non-point source pollution both resulting from anthropogenic activities have been projected to affect plant reproduction and growth in wetlands worldwide.In order to predict and mitigate impacts of these anthropogenic activities,it is important to investigate how marsh plants respond to such environmental changes.Methods In this study,Bolboschoenus planiculmis,a tuberous sedge with a wide distribution range in Eurasia,was selected to examine the effect of air temperature changes(15,20 and 25℃over 24 h;20/10 and 30/15℃,day/night)and K supply(0,1,3,9 and 18 mmol/L)on its reproductive and growth traits in climate chambers.Important Findings We found that high constant temperatures(20 and 25℃)were more beneficial for tuberization of B.planiculmis than high alternating temperatures(30/15℃),whereas aboveground biomass and shoot height were generally largest at high temperatures(30/15 and 25℃).Both reproductive and growth traits of B.planiculmis showed hump-shaped relationships with K supply,with an optimum K concentration of around 1-3 mmol/L.The combination of high constant temperatures and optimal K concentrations promoted reproductive traits the most,whereas the combination of higher temperatures(30/15 and 25℃)and K concentrations up to 9 mmol/L increased growth traits only.We therefore conclude that population abundance of B.planiculmis might benefit from global warming and the additional K supply.