中国农业气象 ›› 2020, Vol. 41 ›› Issue (07): 446-458.doi: 10.3969/j.issn.1000-6362.2020.07.005

• 论文 • 上一篇    下一篇

 基于阈值指标分类法的玉米营养生长阶段受旱程度分级

 麻雪艳,周广胜,李根   

  1.  1. 天津市气象局,天津 300074;2. 中国气象科学研究院,北京 100081;3. 南京信息工程大学气象灾害预警协同创新中心,南京 210044
  • 收稿日期:2020-01-15 出版日期:2020-07-20 发布日期:2020-08-25
  • 作者简介:麻雪艳,E-mail: maxueyan88@126.com
  • 基金资助:
     国家自然科学基金(31901398);公益性行业(气象)科研专项(GYHY201506019);国家重点专项(2016YFD0300106);天津市气象局博士基金(201743bsjj03)

 Classification of Drought Degree during Vegetative Growth Stage of Maize Based on Threshold Indicator Taxa Analysis (TITAN)

 MA Xue-yan , ZHOU Guang-sheng, LI Gen   

  1.  1. Tianjin Meteorological Bureau, Tianjin 300074, China; 2. Chinese Academy of Meteorological Sciences, Beijing 100081;3.Collaborative Innovation Center on Forecast Meteorological Disaster Warning and Assessment, Nanjing University of Information Science & Technology, Nanjing 210044
  • Received:2020-01-15 Online:2020-07-20 Published:2020-08-25
  • Supported by:
     

摘要:  基于田间小区实验,就玉米对不同强度及持续时间的干旱响应进行研究。玉米播种前进行底墒调控,使各小区土壤底墒基本一致。三叶期开始,按照研究区7月多年平均降水量的100%、80%、60%、40%、20%和7%分别进行一次性灌水,此后不再进行灌溉,全生育期利用大型电动遮雨棚遮挡自然降水,随生育时间推移形成6个不同初始土壤水分梯度的持续干旱过程。分析不同处理玉米营养生长阶段(三叶期-拔节期)的形态(株高、叶面积)和生物量(茎干重、叶干重、总干重)指标对干旱程度的响应规律,采用阈值指标分类法(TITAN)确定各生长指标对干旱程度响应规律发生明显改变的临界点,并基于不同指标响应干旱程度临界点的同步性确定玉米植株水平响应干旱程度(D)的临界点,从而将玉米的受旱等级划分为4个等级。结果表明:当0<D≤0.07时,玉米受到轻旱影响,其形态和生物量指标的平均降幅仅为1.2%~3.0%;当0.07<D≤0.47时,玉米受到中旱影响,叶面积和株高的平均降幅分别为15.9%和8.6%,茎、叶干重及总干重的平均降幅分别为18.8%、15.4%和12.4%;当0.47<D≤0.73时,玉米受到重旱影响,叶面积的平均降幅为37.8%,株高的平均降幅为16.9%,茎、叶干重及总干重的平均降幅分别为43.3%、45.2%和28.9%;当0.73<D≤1时,玉米受到特旱影响,叶面积和株高的平均降幅分别为83.6%和53.3%,叶干重和茎干重的降幅均高达90%以上,总干重的平均降幅达87.0%。研究结果可为作物干旱受灾程度的定量分级与评价提供方法和依据。

关键词:  玉米, 持续干旱, 受旱程度, 定量分级, 阈值指标分类法(TITAN)

Abstract:  Drought was a major disaster that limited the growth and yield of crops worldwide. The loss of crop output caused by drought even exceeds the sum of the losses caused by all other factors, and was the most important factor threatening world food security. The influence of drought on crops was closely related to drought intensity, drought duration and the development stage of crops. It was of great significance for efficient agricultural drought prevention and drought relief to accurately assess the drought damage degree of crops and scientifically classify the drought damage levels of crops. Existing methods on crop drought assessment and grading were mostly based on yield reduction. However, yield reduction reflected the drought damage degree of the entire growth period of crop, which could not be applied to the assessment of crop drought damage degree during certain development period, restricting timely formulation and implementation of disaster prevention and mitigation measures. At present, the assessment and research on the progress of drought were generally based on one or several environmental indicators, such as precipitation, soil moisture, water deficit index, etc., or based on some single growth indicator, such as biomass. On the one hand, drought had a cumulative effect on crops, and the environmental indicators observed at that time could not necessarily reflect current growth state and damage degree of crops. On the other hand, a single growth indicator could not accurately reflect the overall growth status of crops. Since different growth indicators may have different response thresholds to drought degree, different conclusions may be drawn when grading and evaluating the drought degree of crops based on the response thresholds of different growth indicators to drought degree. Therefore, this study intended to investigate the responses of maize growth indicators to drought of different intensity and duration during its vegetative growth period (from the 3-leaf stage to jointing stage) based on a field plot experiment performed in 2014, and put forward a new way to accurately evaluating and classifying drought damage degree of maize based on response synchronicity of multiple growth indicators. In the field plot experiment, six different irrigations were performed during the three-leaf period of maize with the irrigation amounts (named treatments T1-T6) were 150, 120, 90, 60, 30, and 10mm, respectively, equivalent to 100%, 80%, 60%, 40%, 20% and 7% of the local average precipitation in July (150mm), respectively. No extra irrigation was performed thereafter. Precipitation was blocked completely by the auto-rain-shelter during the entire growth period. Then, six continuous drought processes of different initial soil moisture gradients were formed as time proceeded. Observations on soil water content, maize growth indicators were performed every 7-day after the irrigation treatments. Based on the observation data, the response regularity of maize morphological (plant height and leaf area) and biomass (stem dry mass, leaf dry mass, and total dry mass) indicators to the drought degree (D) was studied. By using of Threshold Indicator Taxa Analysis method (TITAN), the response turning points of growth indicators of maize's to drought degree were determined, and based on the response synchronicity of these growth indicators, the response turning point of maize plant level to drought degree was identified. Then the drought degree was divided into 4 levels according to these turning points. The results showed that, when 0<D≤0.07, maize was affected by light drought, and the average decrease of maize growth indicators was only1.2%-3.0%; when 0.07<D≤0.47, maize was affected by medium drought with an average decrease of leaf area of 15.9%, plant height of 8.6%, stem dry mass, leaf dry mass, and total dry mass of 18.8%, 15.4% and 12.4%, respectively; when 0.47<D≤0.73, maize was affected by severe drought with an average decrease of leaf area of 37.8%, plant height of 16.9%, stem dry mass, leaf dry mass and total dry mass of 43.3%, 45.2% and 28.9%, respectively; when 0.73<D≤1, maize was affected by extreme drought, with an average decrease of leaf area of 83.6%, plant height of 53.3%, leaf dry mass and stem dry mass above 90%, and total dry weight of 87.0%. The results would provide a method and basis for quantitative classification and evaluation of drought damage degree of crops.

Key words:  , Maize, Prolonged drought, Drought damage degree, Quantitative classification, Threshold Indicator Taxa Analysis method (TITAN)

中图分类号: