天水市玉米生长对气候变暖的响应

气温变暖已对农作物生长发育产生了较大的影响。利用天水市1968—2009年的气温、高温日数的变化资料,分析近几十年来天水市气温的变化趋势及特点,结合天水市农业科学研究所1980—2005年的玉米生育期资料,对数据进行统计和制图,应用DPS软件计算相关系数。通过分析玉米生育期与温度的关系及变化趋势,建立回归模拟方程,揭示玉米对气候变暖的响应,为探讨当地玉米的适宜播种期和玉米作物带的变迁,进而为种植业结构调整和粮食安全提供理论依据。结果表明,1968—2009年天水市年平均温度一直呈比较平稳的上升趋势,增幅为0.469℃.10a 1;年四季平均气温均呈上升趋势,其中以冬季、春季上升最为明显,年高温在30℃和35℃以上天数均呈逐渐增多趋势。玉米播种期、出苗期有推迟趋势,抽穗期、吐丝期、成熟期随气温的变暖均呈现提前的变化趋势,其中播种期推迟2.7 d.10a 1,出苗期延长0.1 d.10a 1,抽穗期提前3.3d.10a 1,吐丝期提前4.4 d.10a 1,成熟期提前8.7 d.10a 1;在玉米生育期各阶段中,播种—出苗期推迟0.1d.10a 1,出苗—抽穗期缩短3.4 d.10a 1,抽穗—吐丝期缩短1.0 d.10a 1,吐丝—成熟期缩短4.4 d.10a 1;生育期内平均气温升高,促使玉米生长加快,发育期提前,全生育期缩短。玉米在1980—2005年间的千粒重总体呈现下降趋势,极端高温对玉米全生育期和千粒重的影响较大。

Response of corn growth to climate warming in Tianshui City, Gansu Province

Global climate warming is having a significant impact on crop growth and development.Using information on air temperature and days of high temperature for 1968-2009 in Tianshui City,Gansu Province,the trends and characteristics of temperature in recent decades were analyzed for the region.This dataset was combined with that on corn growth for 1980-2005(provided by Tianshui Institute of Agricultural Sciences) to perform statistical analysis and correlation analysis by the DPS system.Regression model equations were then constructed(by analyzing the relationships and trends between corn growth and temperature) to determine the response of corn to climate warming,followed by discussing the periods and appropriate belts for sowing the crop.This provided a theoretical basis for adjustments of planting structures and food security.The results indicated that annual average temperature in Tianshui City steadily increased at a rate of 0.469 °C·10a 1.Positive trends were also noted in both the annual and seasonal average temperatures.Winter and spring temperatures obviously increased and days with annual temperatures above 30 °C and 35 °C gradually increased.While corn sowing and seedling operations delayed,sprouting,silking and maturity phenologies occurred early with warming temperatures.Sowing delayed by 2.7 d·a 1,seedling extend by 0.1 d·10a 1,and sprouting,silking and maturity occurred early by 3.3 d·10a 1,4.4 d·10a 1 and 8.7 d·10a 1,respectively.At various stages of corn growth,the days from sowing to seedling delayed by 0.1 d·10a 1,and seedling to sprouting,sprouting to silking and silking to maturity periods shortened by 3.4 d·10a 1,1.0 d·10a 1 and 4.4 d·10a 1,respectively.Corn growth accelerated,development occurred early and growth period shortened with increasing temperature.The average 1000-kernel weight of corn from 1980 to 2005 declined.Extreme high temperatures greatly impacted the growth period and 1000-kernel weight of corn in the region.