摘要
为准确预知地膜覆盖与作物的匹配情况,该研究针对南疆棉田,在大田试验基础上应用根区水质模型(Root Zone Water Quality Model-version 2,RZWQM2),对2016-2017年籽棉产量及水分利用效率(Water Use Efficiency,WUE)等数据进行模型参数率定与验证,利用验证后的模型模拟地膜覆盖时间55~105 d下以3 d为间隔的地上部生物量、籽棉产量和水分利用效率,并对2018年和2019年不同地膜覆盖时间下棉花生长状况进行预测。结果表明,各层土壤含水率模拟值和实测值之间的均方根误差和均方误差分别在0.02~0.04 cm3/cm3、5.90%~28.66%之间,地上部生物量和籽棉产量的一致性指数分别为0.70~0.93和0.80~0.94。2 a间地上部生物量随地膜覆盖时间的延长而增加,籽棉产量和水分利用效率呈先上升后下降的趋势,其峰值分别出现在91~93 d和97~99 d。因此,在南疆地区选用适宜的地膜覆盖时间为91~99 d,有利于降低残膜污染风险,保持较高的籽棉产量和水分利用效率。
Plastic film mulching plays an important role in Xinjiang cotton production.The main function of mulching is to maintain soil temperature and moisture.Plastic film mulching during the whole growth period may lead to soil temperature overheat and root respiration obstruction.In addition,the biodegradable film is expected to replace traditional plastic films.However,several studies have shown that the degradation period of biodegradable mulch film does not match the growth requirements of cotton.Therefore,balancing the relationship among mulching time,crop growth demand and the changes of farmland environmental factors is the key scientific issue to control the pollution of residual plastic film in Xinjiang.Field experiments were conducted in 2016 and 2017 to investigate the mechanisms behind the effects of mulching time on cotton(Gossypium hirsutum Linn.)growth.Six mulching time(40 d,55 d,70 d,85 d,100 d and whole growing season mulching)were designed.The cotton yield and Water Use Efficiency(WUE)were simulated by using Root Zone Water Quality Model-Version 2(RZWQM2)model.The parameters of the RZWQM2 model were calibrated and verified by the measured data of 2016 and 2017.Then,the formation processes of biomass,yield and water use efficiency under the influence of different mulching times were simulated at intervals of 3 days,and the similar processes mentioned above were predicted in 2018 and 2019.The objective of this work was to provide a decision method for the model to simulate soil moisture changes and predict crop yields under the conditions of crop mulching,and it would be helpful to determine the reasonable mulching time and reduce the residual plastic film pollution in cotton field on the premise of ensuring high and stable yield.The model validation results showed that the Root Mean Square Error(RMSE)and Mean Square Error(MRE)between the simulated and measured soil water content in each layer of soil ranged from 0.02 to 0.04 cm^(3)/cm^(3) and 5.90%to 28.66%.The simulation effect of the upper soil layer was not as good as that of the lower soil layer because of more complex temporal and spatial changes of soil surface organic matter content,macropores and other properties than deep soils.The aboveground biomass of two years increased with the extension of mulching time,and the seed cotton yield and WUE showed a trend of first increasing and then decreasing.The growth rate of seed cotton yield and water use efficiency was the highest when the mulching time was 73-81 d,and the yield was higher when the mulching time was mid-to-early August.At this time,the cotton canopy has been closed,and the surface receives less solar radiation,which maximally inhibits soil evaporation,thus reducing the non-productive water consumption and increasing the proportion of productive water consumption.At the same time,the soil ventilation and air permeability are improved after uncovering the film,and the soil microbial activity is enhanced.Therefore,it can be concluded that uncovering film in this period had little effect on cotton growth,and the tensile strength of mulching film at this time was still high,which was more conducive to mechanical recovery.The optimum mulching time of 91-99 d in southern Xinjiang was beneficial to reduce the risk of residual film contamination and maintain high seed cotton yield and water use efficiency.The mechanism of film mulching cycle on key physiological and ecological processes,such as water consumption structure transformation,salt distribution,nutrient migration and absorption in cotton field need further studies.Related work needs to be carried out in the future research,so as to improve the level of cognition and optimize relevant supporting measures.
作者
夏文
林涛
褚晓升
丁奠元
颜安
尔晨
汤秋香
Xia Wen;Lin Tao;Chu Xiaosheng;Ding Dianyuan;Yan An;Er Chen;Tang Qiuxiang(College of Agronomy,Engineering Research Centre of Cotton of Ministry of Education,Xinjiang Agricultural University,Urumqi 830052,China;Institute of Cash Crops Research,Xinjiang Academy of Agricultural Sciences,Urumqi 830091,China;Institute of Water-saving Agriculture in Arid Areas of China,Northwest A&F University,Yangling 712100,China;Hydraulic Science and Engineering College,Yangzhou University,Yangzhou 225009,China;Xinjiang Key Laboratory of Grassland Restoration and Environmental Information,Urumqi 830052,China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2021年第11期140-150,共11页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家自然科学基金项目(31960386)
新疆维吾尔自治区重大科技专项(2020A01002-4)
新疆维吾尔自治区高校科研计划项目(XJEDU2019I012)
新疆农业科学院重点培育专项(XJLCPY-2020003)。
