水稻组合气象灾害的一个实例研究

A Case Study on Overlapped Chilling with Heat Injury on Rice Crop

摘要: 气候异常变化对作物生产的影响正日趋增大，但气候异常究竟会以何种方式影响作物生长还鲜见报道。2007 年位于江汉平原(以湖北省荆州市为中心)发生罕见的中稻结实障碍，且田间受害症状表现为典型的高、低温致害症状。通过对田间试验和大范围生产调查，对水稻受害与气候条件之间的关系进行了因果对应分析。结果表明，7 月 20 日~7 月 25 日期间，部分地区有一个罕见的降温过程，日均温低达 20℃，达到籼稻品种孕穗期敏感温度范围；8 月 6 日~8 月 10 日，部分地区出现一个连续高温天气过程，日均温或最高温度达到日均气温 ≥ 30℃或最高气温 ≥ 35℃，将各地受害程度与气象条件进行比对、综合分析，将本年度中稻结实障碍因不同地区分为 3 类，分别为低温主导型、高温主导型和低、高温叠加组合型。其中以低、高温叠加组合型危害程度最重，即它既受到减数分裂期的低温危害也受到了开花期的高温危害。此实例启示，全球气候变暖将会给作物生产造成更为复杂和严重的灾害，相应应对技术的研究显得十分紧迫。

Abstract: Crops are increasingly influenced by abnormal meteorological conditions nowadays. Meanwhile we know little on how the abnormal meteorological factors would impact the crop growth. A rare sterility hazard, a typical damage from abnormal temperature, happened to mid-rice at anthesis stage in Jianghan Plain, Hubei, China in 2007. But it is bewildering to determine the exact cause for the hazard. We compared the data from field experiment, the varieties tests over the area and the meteorological records across the damaging period to find a possible cause for rice sterility. The result showed that during 20, July to 25, July, some parts of the area undergone a shape decrease of temperature, and the daily mean temperature was lower than 20˚C exactly and surpassed the chilling damaging point for ear-formation. Meanwhile, from 6 August to 10 August, the time when rice was flowering, a continuous temperature lift happened, namely more than 30˚C in daily mean temperature or 35˚C in daily maximum temperature. In addition, the varieties that flowered at 6-13 August should undergone their meiosis stage of pollen mother cells in several days after 24 July. By matching the injuries data from the different areas against the meteorological regimes those crops experienced, we concluded with a category map of the areas in rice sterility degree: some are caused mostly by the cold weather; some are mostly by the high temperature weather; and some by an overlapped bad weather, namely cold weather at first at meiosis, then heat at anthesis. Among them, the overlapped type happened at a moderate scale in area but the loss was the biggest. This case suggests that global warming may induce more complex and severer damage to crops, so the countermeasures are urgently needed.