加拿大主要农田作物临界气象指标

Critical agrometeorological indicators for major field crops in Canada

根据加拿大主要农田作物生长发育对天气与气候条件的要求、农业气象学与气候学原理以及全球气候变化对农作物生产的影响和发展趋势,选择6个关键性气象因素(极端气温、强降水、强风、冷冻、土壤极端水分和作物生产有效热能条件),开发和评价12个农业气象临界指标(寒潮及热浪天数、日及旬最大降水量、日最大风速、强风天数、无霜期及冰冻期天数、标准降水系数、季节性水分亏缺、作物生长有效积温和累积热能单位)。这些指标可供在该国各农产区科学规划和合理发展各类农田作物生产,包括喜暖性和喜凉性一年生草本作物,越冬性二年生及多年生草本及木本作物。该研究还依据该国这三类主要农田作物对临界温度和水分的需求,以及加拿大农田作物生长期和越冬期的天气和气候特征,建立了在任意农业生产年份中各类农田作物生长起始和终止日期的模式。本研究结果能用于指导该国将来在不同农产区适地适时种植适宜的农田作物和高效地经营与管理农场,同时可为农业生产咨询、政策制定和合理决策提供科学依据,也可供其他国家或地区开展类似的科学研究参考。

According to the requirement for major field-crops＇ growth and development on weather and climate conditions in Canada, principles of agricultural meteorology and climatology, as well as impacts and trends of global climate change on the crop production, six key agrometeorological factors （ extreme air temperature, heavy precipitation, strong wind, freezing, extreme soil moisture and effective heat-ener- gy conditions for crop production ） were selected for development and evaluation of twelve critical agrometeorological indicators （cool spell and heat wave days, maximal daily and ten-day precipitations, maximal daily wind speed, strong wind days, frost-free and freezing days, standardized precipitation in- dex, seasonal water deficit, effective growing degree days and crop cumulative heat units）. They can be used for scientific regionalization and rational development of different types of field crops, including warm season crops and cool season crops of annual herbaceous species, and over-wintering crops of bi- ennial and perennial herbaceous and woody species in various agricultural regions across the country.This study is also based on plant growth and development requirements for cardinal temperatures and water conditions for three types of major field crops and actual weather and climate characteristics dur- ing crop growing and overwintering seasons in any agricultural years to determine growing season start- ing and ending days of various field crops in Canada. The results can be used for rational arrangement, optimal selection and proper plantation of suitable field crops in various agricultural regions of the coun- try, efficient farm operation and management, science advice, policy development and decision-making, as well as similar scientific researches in other countries and regions in the future.