摘要
【目的】探究耦合气象、土壤水分和氮素状态对青稞生长的影响机理,构建西藏地区青稞生长动力学模型。【方法】于2016─2017年在拉萨市墨达灌区开展了试验研究,测定了青稞生育期气象参数、土壤水分和氮素质量浓度变化过程。基于日光合作用和呼吸作用模拟日干物质增长量,提出了开关因子计算青稞由发育生长到生殖生长的临界时间,根据叶面积指数变化和干物质质量平衡,以及青稞生育期干物质分配和转化关系发展了干物质日增长量分配关系,基于动态平衡原理,提出了气象条件、土壤含水率和氮素影响下的干物质胁迫关系。基于2016年观测值率定模型参数,模拟2017年青稞生长。【结果】模型在本地参数下,模拟结果与实测结果符合良好,Nash-Sutcliffe系数和相对均方根误差分别为0.84和0.05;变化条件下,能够达到较好的模拟精度,Nash-Sutcliffe系数和相对均方根误差分别为0.67和0.11。【结论】所提出的模型能够描述多因子胁迫条件下的青稞生长动力学机制,具有完备的物理机制。
【Objective】Hulless barley is a stable crop in Tibet plateau and this paper presents a model to simulate its growth under multiple abiotic stresses.【Method】Field and lab experiments were conducted at Moda Irrigation District in Lhasa and the Irrigation and Drainage lab at Nyingchi during the 2016-2017 growth season respectively.During the experiment,meteorological data,soil water content and soil nitrogen were measured.Daily dry matters were simulated based on photosynthesis and respiration of the crop,in which a switch factor was used to determine the time at which the crop changed from developmental stage to reproduction stage.The daily increased dry matter were partitioned into root,stem,leaf and ear using the mass balance between leaf development and crop growth.The dry matters in the root,stem and leaf were allowed be transformed to the ears in the reproduction stage.The combined stress of water and nitrogen were described using calibrated functions,and the values of the model parameters were obtained by fitting the measured data in Moda Irrigation District in 2016,and they were then used to model the crop growth in 2017.【Result】The Nash-Sutcliffe coefficient and the relative root mean square error between the measured and simulated hulless barley dry matters were 0.84 and 0.05 respectively using the parameters estimated locally,and were 0.67 and 0.11 respectively using the parameters under changing condition.【Conclusion】The proposed model is able to describe growth of the hulless barley under the combined water and nitrogen stresses.
作者
李玉庆
蒙强
刘静霞
张文贤
罗红英
周祖昊
LI Yuqing;MENG Qiang;LIU Jingxia;ZHANG Wenxian;LUO Hongying;ZHOU Zuhao(School of Hydraulicand Civil Engineering,Tibet Agricultural and Animal University,Nyingchi 860000,China;State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,China Institute of Water Resources and Hydropower Research,Beijing 100038,China)
出处
《灌溉排水学报》
CSCD
北大核心
2019年第2期1-8,共8页
Journal of Irrigation and Drainage
基金
国家自然科学基金项目(91647109
51679257
51769035)
西藏自治区级重点实验室"西藏土木水利电力工程技术研究中心"开放基金项目
高校联合项目基金项目(szjj2015-040)
关键词
青稞
模型
生长动力学
氮素
农田气象条件
西藏高原
hulless barley
model
nitrogen
farmland weather conditions
growth kinetics
Tibet plateau
