四川石渠垂穗披碱草的物候期及其与气象因子的相关性

Phenological Period of Elymus nutans and its Correlations with Meteorological Factors in Shiqu County,Sichuan

为促进垂穗披碱草的产业化发展及牧业气象辅助决策服务提供科技支撑,利用1961-2017年四川省石渠国家基本气象站气象资料和1984-2017年石渠县农业气象试验站天然牧草垂穗披碱草生育期的观测资料,采用数理统计和回归模型等相关分析方法研究垂穗披碱草的物候期变化及其与气象因子的相关性。结果表明:1960年以来,石渠县年平均气温呈上升趋势,气候倾向率为0.359℃/10a,年降水量呈微小的增加趋势,线性倾向率为9.45 mm/10a;随着气候的变化,石渠垂穗披碱草整个生育期缩短,全生育期为111~180 d,多年平均为137 d。返青期和分蘖期分别推迟7.2 d/10a和6.4 d/10a,抽穗、开花、种子成熟和枯黄期分别提前2 d/10a、2.9 d/10a、5.3 d/10a和7.8 d/10a;石渠县垂穗披碱草返青期≥0℃日平均气温初日提前,返青期前1个月的平均气温越高和降水量越多则石渠垂穗披碱草返青期提前,由于夏季气温的升高,石渠垂穗披碱草抽穗、开花和种子成熟期提前;在秋季暖湿化倾向的综合作用下,近年来枯黄期以提前居多。石渠县垂穗披碱草返青期与前期≥0℃积温成负相关,其余各生育期前期积温偏小,生育期起始时间呈推后变化趋势。

The variation in phenological period of Elymus nutans and correlations between phenological periods and meteorological factors are analyzed by mathematical statistics and regression model based on meteorological data recorded by Shiqu National Basic Meteorological Station during 1961-2017 and the observation data of E.nutans growth period recorded by Shiqu Agricultural Meteorological Experiment Station during 1984-2017 to provide the technological support for promoting industrial development of E.nutans and formulating meteorological aid decision service to animal husbandry in Shiqu County,Sichuan.Result:The annual average temperature in Shiqu County shows a rising trend with 0.359℃/10 a climatic tendency rate and the annual precipitation shows a slight rising trend with 9.45 mm/10 a linear tendency rate during 1961-2017.The whole growth period of E.nutans is 111-180 d with an average of 137 d and shortens with climatic variation.The starting day at returning green and tillering stage of E.nutans delays by 7.2 d/10 a and 6.4 d/10 a respectively.The starting day at heading,flowering,seed maturity and yellowing stage of E.nutans advances by 2 d/10 a,2.9 d/10 a,5.3 d/10 a and 7.8/10 a separately.The first day of≥0℃daily average temperature at returning green stage is ahead of time.The starting day at returning green stage is ahead of time due to rising average temperature and more precipitation in one month before returning green stage.The starting day at heading,flowering and seed maturity stage of E.nutans advances with rising temperature in summer.The starting day at yellowing stage often is ahead of time due to the comprehensive action of warm and wet tendency in autumn in recent years.The starting day at returning green stage of E.nutans is negatively related to≥0℃accumulated temperature during earlier days before returning green stage.The starting day at tillering,heading,flowering,seed maturity and yellowing stage shows the postponing variation trend due to low accumulated temperature during earlier days before different growth stages in Shiqu County.