黄土丘陵区退耕草地群落优势种叶片光合生理对氮磷添加的响应  

Leaf photosynthetic responses to nitrogen and phosphorus additions of dominant species in farm⁃withdrawn grassland in the loess hilly⁃gully region

作　　者：赖帅彬 徐升 简春霞 陈志飞 周俊杰 杨全 王智[1,3] 徐炳成[1,3] LAI Shuaibin;XU Sheng;JIAN Chunxia;CHEN Zhifei;ZHOU Junjie;YANG Quan;WANG Zhi;XU Bingcheng(State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Institute of Soil and Water Conservation,Northwest Agriculture and Forestry University,Yangling 712100,China;Jilin Agricultural Science and Technology College,Jilin 132101,China;Institute of Soil and Water Conservation,Chinese Academy of Sciences and Ministry of Water Resources,Yangling 712100,China)

机构地区：[1]西北农林科技大学黄土高原土壤侵蚀与旱地农业国家重点实验室,杨凌712100 [2]吉林农业科技学院,吉林132101 [3]中国科学院水利部水土保持研究所,杨凌712100

出　　处：《生态学报》2021年第13期5454-5464,共11页Acta Ecologica Sinica

基　　金：国家自然科学基金(41771553);国家“十三五”重点研发计划项目(2016YFC0501703)。

摘　　要：以黄土丘陵区退耕草地群落典型优势种白羊草、长芒草和达乌里胡枝子为研究对象,测定不同氮磷(主区N:0,50,100 kg N hm^(-2)a^(-1);副区P:0,40,80 kg P_(2)O_(5) hm^(-2)a^(-1))添加处理下叶片光合气体交换参数、叶绿素荧光参数、叶片氮磷含量、光合氮利用效率(PNUE)和光合磷利用效率(PPUE),探究不同优势种光合生理特征对外源氮磷添加的响应特征与物种差异。结果表明:单独氮添加下,3个优势种的净光合速率(P_(n))、蒸腾速率、水分利用效率(WUE_(i))、气孔限制值(Ls)和光系统Ⅱ(PSⅡ)活性高于或显著高于未施肥处理,白羊草和达乌里胡枝子的PNUE和PPUE以及长芒草的PPUE显著增加。单独磷添加下,仅达乌里胡枝子的P_(n)、WUE_(i)、Ls和PNUE相比未施肥处理显著增加。氮磷共同添加下,50 kg N hm^(-2)a^(-1)处理下,施磷后达乌里胡枝子的P_(n)以及三个优势种的PNUE显著增加,白羊草的PPUE显著降低;100 kg N hm^(-2)a^(-1)处理下,施磷后达乌里胡枝子的P_(n)和PNUE均显著增加,白羊草PPUE和长芒草的PNUE的仅在40 kg P_(2)O_(5) hm^(-2)a^(-1)处理下显著增加。3个优势种的P_(n)均与PSⅡ最大光化学效率和叶片氮含量呈显著正相关关系,长芒草和达乌里胡枝子的P_(n)与PSⅡ潜在活性和叶片磷含量呈显著正相关关系。总体表明,氮磷对黄土丘陵区退耕草地优势种光合生理具有一定的交互作用,物种属性和施肥水平影响其光合生理特征响应程度。In order to clarify the photosynthetics characteristics and difference in response to nitrogen and phosphorus additions,three dominant species(Bothriochloa ischaemum,Stipa bungeana and Lespedeza davurica)of farm⁃withdrawn grassland communities in the loess hilly⁃gully region were selected.A split⁃plot experiment including three N(0,50,and 100 kg N hm^(-2)a^(-1))and three P(0,40,and 80 kg P_(2)O_(5) hm^(-2)a^(-1))treatments was conducted to investigate the effect of N and P addition on net photosynthetic rate,transpiration rate,water use efficiency,stomatal limitation,initial fluorescence,photosystemⅡmaximal efficiency,photosystemⅡpotential activity,leaf N content,leaf P content,photosynthetic nitrogen use efficiency and photosynthetic phosphorus use efficiency of the three dominant species.Results showed that net photosynthetic rate,transpiration rate,water use efficiency,stomatal limitation,photosystemⅡmaximal efficiency and photosystemⅡpotential activity under 50 and 100 kg N hm^(-2)a^(-1) treatments were significantly higher than those under no N addition treatment of three dominant species.Nitrogen addition significantly increased photosynthetic nitrogen use efficiency and photosynthetic phosphorus use efficiency of B.ischaemum and L.davurica.The photosynthetic phosphorus use efficiency of S.bungeana.net photosynthetic rate,water use efficiency,stomatal limitation and photosynthetic phosphorus use efficiency under 40 kg P_(2)O_(5) hm^(-2)a^(-1) and 80 kg P_(2)O_(5) hm^(-2)a^(-1)treatments were significantly higher than those of L.davurica under no P addition treatment.Under 50 kg N hm^(-2)a^(-1)treatment,compared with no P application,net photosynthetic rate of L.davurica and photosynthetic nitrogen use efficiency of the three dominant species increased significantly,and photosynthetic phosphorus use efficiency of B.ischaemum decreased significantly at 40 kg P_(2)O_(5) hm^(-2)a^(-1) and 80 kg P_(2)O_(5) hm^(-2)a^(-1) treatments;while under 100 kg N hm^(-2)a^(-1)treatment,compared with no P appli

关 键 词：退耕草地 优势种 光合作用 叶绿素荧光 光合养分利用效率 

分 类 号：S812[农业科学—草业科学]