黄土高原红枣种植区积温变化特征分析

为了揭示黄土高原红枣种植区积温的变化特征，为红枣产业的布局和科学管理提供依据。利用1971—2010年12个气象站日平均气温资料，运用线性倾向估计、M-K及小波分析等方法，对≥0℃，5℃，10℃积温及负积温的变化特征进行了分析。结果表明，40年来≥0℃，5℃，10℃积温呈增加趋势，气候倾向率分别为64.557℃/10 a，66.235℃/10 a，48.023℃/10 a。负积温呈减少趋势，气候倾向率为-33.759℃/10 a。持续日数呈增加趋势，各界限温度初日呈提前趋势，终日除10℃外均呈推后趋势。各界限温度积温均发生突变现象，负积温突变出现最早1986年，其次为≥0℃积温1995年，≥5℃、≥10℃积温1996年；各界限温度积温变化存在多时间尺度的周期变化特征，具有2～4，9～11，32～33 a左右的周期振荡，其中32～33 a左右的周期最为明显。黄土高原红枣种植区近40 a来0℃以上各界限温度积温和持续时间呈增加趋势，热量资源明显改善，适宜种植红枣的区域扩大；但需采取有效措施防御可能发生的干旱灾害及红枣病虫害。

Variation Characteristics of the Accumulated Temperature of Jujube Planting Zones in the Hilly Region of the Loess Plateau over the Past 40 Years

In order to understand the variation characteristics of accumulated temperature of jujube planting zones in the hilly region of the Loess Plateau and provide decision basis for distribution and scientific management of jujube, based on the daily temperature in twelve weather stations of the jujube planting zones in the hilly region of the Loess Plateau from 1971 to 2010, we analyzed the variation characteristics of ≥ 0℃, ≥ 5℃, ≥ 10℃accumulated temperatures and negative accumulated temperature change by means of linear trend estimates, M-K test and Morlet wavelet analysis. The results indicated that the ≥ 0℃, ≥ 5℃, ≥ 10℃ accumulated temperatures showed an increasing trend over 40 years and they are increasing significantly by 64.557℃/decade, 66.235℃/decaced and 48.023℃/decade, respectively. The negative accumulated temperatures decreased by 33.759℃/decade. The lasting days of accumulated temperature have increased too, the trend of beginning dates of accumulated temperatures appeared ahead. On the other hand, the ending dates were delayed except ≥ 10℃ accumulated temperature. The main boundary temperature had an obvious warming mutation, the negative accumulated temperature changed at the earliest abruptly in 1986, followed by ≥ 0℃ accumulated temperature(1995), ≥ 5℃, ≥ 10℃ accumulated temperatures(1996). The main boundary temperature was fluctuating periodically with the variation of temporal scale, with 2~4,9~11,32~33 years fluctuation. The accumulated temperature of the main boundary and the lasting days had increasing trend and the heat resources improved significantly, the suitability areas for jujube expanded, but effective measures need to be taken for preventing the drought disaster and insect pests and diseases.