CN-122022440-A - Crop regional low-temperature freeze injury assessment method

CN122022440ACN 122022440 ACN122022440 ACN 122022440ACN-122022440-A

Abstract

The invention belongs to the technical field of agricultural freeze injury assessment, and discloses a crop regional low-temperature freeze injury assessment method which comprises the steps of S1, determining freeze injury meteorological factors and critical temperatures of crop freeze injury, S2, constructing a crop freeze injury intensity index model, S3, forming a time sequence of all low-temperature freeze injury intensity indexes in a time zone, S4, classifying regional low-temperature freeze injury intensities, respectively carrying out space-time distribution characteristic analysis on various indexes, evaluating the intensity distribution of the various low-temperature freeze injury indexes, S5, establishing a low-temperature freeze injury comprehensive risk index model, S6, carrying out space-time distribution analysis on the low-temperature freeze injury comprehensive risk indexes, and carrying out regional low-temperature freeze injury risk assessment, and constructing a low-temperature freeze injury intensity index model and a low-temperature freeze injury comprehensive risk index model by combining a plurality of key meteorological disaster causing factors, a plurality of influence processes and crop freeze injury critical indexes.

Inventors

YU HUIKANG
LIN XIAORU
HUANG WENLIN
CHEN YUANMIN

Assignees

福建省福鼎市气象局

Dates

Publication Date: 20260512
Application Date: 20251030

Claims (4)

1. A method for evaluating regional low-temperature freeze injury of crops, which is characterized by comprising the following steps: s1, determining critical meteorological factors of freeze injury and critical temperature of freeze injury of crops based on regional historical low-temperature freeze injury processes and historical freeze injury records of crops; S2, constructing a crop freeze injury intensity index model according to the freeze injury key meteorological factors and the critical temperature of crop freeze injury, wherein the freeze injury intensity index model comprises a low-temperature freeze injury intensity index model, an accumulated low-temperature freeze injury intensity index model, an average low-temperature freeze injury intensity index model and an extreme low-temperature freeze injury intensity index model; s3, forming a time sequence of all low-temperature freeze injury intensity indexes of each site in a historical time period region; S4, dividing regional low-temperature freeze injury intensity levels into mild, moderate, severe and extra heavy by applying an optimal probability function fitting method or a percentile method, and respectively carrying out space-time distribution characteristic analysis on the accumulated low-temperature freeze injury intensity index, the average low-temperature freeze injury intensity index and the extreme low-temperature freeze injury intensity index to evaluate the intensity distribution of various low-temperature freeze injury indexes; s5, establishing a low-temperature freeze injury comprehensive risk index model according to the occurrence times of low-temperature freeze injury of crops in a historical time period and the statistical data of the occurrence probability of the freeze injury of each level; s6, carrying out space-time distribution analysis on the low-temperature freeze injury comprehensive risk index, and carrying out regional low-temperature freeze injury risk assessment.
2. A crop regional low-temperature freeze injury assessment method according to claim 1, wherein in S1, the key meteorological factors comprise the number of continuous days of the low-temperature freeze injury process, the daily average minimum air temperature of the low-temperature freeze injury process and the extreme minimum air temperature of the low-temperature freeze injury process.
3. The method for evaluating regional low-temperature freeze injury of crops according to claim 1, wherein in S2, the expression of the low-temperature freeze injury intensity index model is: ; Wherein h represents a freeze injury intensity index of a certain low-temperature freeze injury process of a certain station, T represents a crop freeze injury critical threshold temperature, td represents a continuous day number of the certain low-temperature freeze injury process of the certain station, tm represents a daily average minimum air temperature of the certain low-temperature freeze injury process of the certain station, tr represents an extreme minimum air temperature of the certain low-temperature freeze injury process of the certain station, and a 1 、a 2 、a 3 represents weight coefficients of Td, tm and Tr respectively; The expression of the cumulative low temperature freeze injury intensity index model is: ; wherein H represents an accumulated low-temperature freeze injury intensity index of a low-temperature freeze injury process in a certain time period of a certain station, and n represents the occurrence times of the low-temperature freeze injury process in the certain time period of the certain station; The expression of the average low-temperature freeze injury intensity index model is as follows: ; In the formula, An average low temperature freeze injury intensity index representing a low temperature freeze injury process at a station for a period of time; The expression of the extremely low temperature freeze injury intensity index model is as follows: ; Where H max represents the extreme low temperature freeze injury intensity index of the low temperature freeze injury process at a station for a certain period of time.
4. The method for regional low-temperature freeze injury assessment of crops according to claim 1, wherein in S5, the expression of the comprehensive risk index model of low-temperature freeze injury is: ; Wherein a is a low-temperature freezing injury risk index, j=1-4 represents 4 freezing injury grades of mild, moderate, severe and extra-heavy respectively, C j is a weight coefficient corresponding to each grade, P j is the occurrence frequency of each grade, and G j is the occurrence probability of each grade.

Description

Crop regional low-temperature freeze injury assessment method Technical Field The invention relates to the technical field of agricultural freeze injury assessment, in particular to a crop regional low-temperature freeze injury assessment method. Background Although the climate has generally been warming for the 21 st century, there has been an increasing trend in the potential impact of low temperature disasters, low temperature freeze injury is one of the important factors that harm and lead to reduced yield in overwintering crops, and sudden freeze injury, especially in extreme low temperature weather processes, causes huge economic losses in agriculture. The occurrence of freeze injury depends on both weather conditions and the crop itself. Meteorological factors are dominant factors of freeze injury, and risk analysis of disaster causing factors is one of important directions of modern disaster risk assessment. The existing cold damage assessment technology mostly adopts a single meteorological factor (such as extreme minimum air temperature), and the disaster influence assessment is not objective, real and representative enough, so that the assessment result is one-sided. Disclosure of Invention The invention aims to provide a crop regional low-temperature freeze injury assessment method, which is used for constructing a low-temperature freeze injury intensity index model and a low-temperature freeze injury comprehensive risk index model by combining a plurality of key meteorological disaster factors, a plurality of influence processes and crop freeze injury critical threshold indexes, and carrying out comprehensive, objective, real and quantitative analysis and assessment on regional low-temperature freeze injury. Solving the problems in the background technology. In order to achieve the above object, the present invention provides the following technical solutions: A method for evaluating regional low-temperature freeze injury of crops, comprising the following steps: s1, determining critical meteorological factors of freeze injury and critical temperature of freeze injury of crops based on regional historical low-temperature freeze injury processes and historical freeze injury records of crops; S2, constructing a crop freeze injury intensity index model according to the freeze injury key meteorological factors and the critical temperature of crop freeze injury, wherein the freeze injury intensity index model comprises a low-temperature freeze injury intensity index model, an accumulated low-temperature freeze injury intensity index model, an average low-temperature freeze injury intensity index model and an extreme low-temperature freeze injury intensity index model; s3, forming a time sequence of all low-temperature freeze injury intensity indexes of each site in a historical time period region; S4, dividing regional low-temperature freeze injury intensity levels into mild, moderate, severe and extra heavy by applying an optimal probability function fitting method or a percentile method, and respectively carrying out space-time distribution characteristic analysis on the accumulated low-temperature freeze injury intensity index, the average low-temperature freeze injury intensity index and the extreme low-temperature freeze injury intensity index to evaluate the intensity distribution of various low-temperature freeze injury indexes; s5, establishing a low-temperature freeze injury comprehensive risk index model according to the occurrence times of low-temperature freeze injury of crops in a historical time period and the statistical data of the occurrence probability of the freeze injury of each level; s6, carrying out space-time distribution analysis on the low-temperature freeze injury comprehensive risk index, and carrying out regional low-temperature freeze injury risk assessment. Further, in S1, the key meteorological factors include the number of consecutive days of the low temperature freeze injury process, the daily average minimum air temperature of the low temperature freeze injury process, and the extreme minimum air temperature of the low temperature freeze injury process. Further, in S2, the expression of the low-temperature freeze injury intensity index model is: Wherein h represents a freeze injury intensity index of a certain low-temperature freeze injury process of a certain station, T represents a crop freeze injury critical threshold temperature, td represents a continuous day number of the certain low-temperature freeze injury process of the certain station, tm represents a daily average minimum air temperature of the certain low-temperature freeze injury process of the certain station, tr represents an extreme minimum air temperature of the certain low-temperature freeze injury process of the certain station, and a 1、a2、a3 represents weight coefficients of Td, tm and Tr respectively; The expression of the cumulative low temperature freeze injury intensity index model is: wher