吴丽萍, 陈洪松, 连晋姣, 付智勇, 王升. 喀斯特与非喀斯特地区参考作物蒸散量时空变化分析——以广西壮族自治区为例[J]. 中国生态农业学报(中英文), 2017, 25(10): 1508-1517. DOI: 10.13930/j.cnki.cjea.170293
引用本文: 吴丽萍, 陈洪松, 连晋姣, 付智勇, 王升. 喀斯特与非喀斯特地区参考作物蒸散量时空变化分析——以广西壮族自治区为例[J]. 中国生态农业学报(中英文), 2017, 25(10): 1508-1517. DOI: 10.13930/j.cnki.cjea.170293
WU Liping, CHEN Hongsong, LIAN Jinjiao, FU Zhiyong, WANG Sheng. Spatio-temporal variation in reference evapotranspiration in recent 50 years in karst and non-karst areas in Guangxi Zhuang Autonomous Region[J]. Chinese Journal of Eco-Agriculture, 2017, 25(10): 1508-1517. DOI: 10.13930/j.cnki.cjea.170293
Citation: WU Liping, CHEN Hongsong, LIAN Jinjiao, FU Zhiyong, WANG Sheng. Spatio-temporal variation in reference evapotranspiration in recent 50 years in karst and non-karst areas in Guangxi Zhuang Autonomous Region[J]. Chinese Journal of Eco-Agriculture, 2017, 25(10): 1508-1517. DOI: 10.13930/j.cnki.cjea.170293

喀斯特与非喀斯特地区参考作物蒸散量时空变化分析——以广西壮族自治区为例

Spatio-temporal variation in reference evapotranspiration in recent 50 years in karst and non-karst areas in Guangxi Zhuang Autonomous Region

  • 摘要: 参考作物蒸散量(ET0)是确定植被生态系统需水量的关键因子,其时空分布特征及主要影响因素分析对于制定植被恢复策略与区域水资源配置方案具有重要意义。本文基于FAO-56 Penman-Monteith公式和广西地区25个气象站点1960-2010年的逐日资料,计算了各站点的ET0,在此基础上采用GIS的克里金插值、Spearman秩次相关法和通径分析方法分析了广西喀斯特与非喀斯特地区ET0的时空变化特征及其影响因子。结果表明,51年来广西各站点多年平均ET0为1 138 mm·a-1;空间分布呈由南向北、由低纬度向高纬度递减的特征,高值区主要分布在非喀斯特地区,低值区主要分布在喀斯特地区。喀斯特与非喀斯特地区年ET0累积距平曲线均呈"N"型分布;20世纪70年代最高,90年代最低,21世纪以来年ET0有所回升,但仍低于51年平均值。此外,喀斯特地区ET0年际变化小于非喀斯特地区。日照时数、风速和平均温度是影响非喀斯特地区年ET0变化的主要气象因子,而相对湿度则通过与其他气象因子的相互作用间接对喀斯特地区年ET0的变化产生较大影响。在季节尺度上,日照时数和平均气温在各季节都是ET0最主要的影响因子,与ET0呈正相关关系;风速在喀斯特地区冬、春两季对ET0的间接作用系数为负,在非喀斯特地区并未发现这一现象。了解不同地区ET0的变化趋势是植被生态需水定额计算的必要措施。

     

    Abstract: Reference evapotranspiration (ET0) is the water requirement of plants driven by meteorological factors. It is critical for restoration of vegetation and regional water resources management. In Southwest China where karst landforms are common, the ecological environment is fragile. Extreme drought and flood events are usually caused by declining annual precipitation and large amounts of precipitation within short time periods. The response of ET0 to global climate change is a key in the assessment of the effect of climate change on hydrology. Therefore, it was important to explore the spatial and temporal variations and the related driving factors of ET0. Based on data collected from 25 meteorological stations in Guangxi for the 1960-2010, daily ET0 was computed using the FAO-56 Penman-Monteith equation. The spatio-temporal variations and the driving factors of ET0 in Guangxi karst and non-karst areas were analyzed separately using Kriging interpolations, cumulative anomalies and spearman rank correlation at seasonal and annual scales. The driving factors of ET0 in karst and non-karst areas were analyzed using the path-analysis method. Results showed that ET0 decreased gradually from southeast to northwest of the study area, with an average rate of 1 138 mm·a-1 during the studied period. High ET0 was mainly distributed in non-karst areas and low ET0 in karst areas. For different seasons, ET0 values from stations in non-karst areas were generally higher than those from stations in karst areas. Mean monthly ET0 in both karst areas and non-karst areas tracked a unimodal curve, with relatively high ET0 for the period from May to September. Non-karst areas had higher ET0 variations than karst areas. The average monthly ET0 in non-karst areas was 95 mm and that in karst areas 64 mm. Summer ET0 was highest and winter ET0 lowest. In the recent 51 years, annual ET0 for both karst and non-karst areas tracked N-shaped distribution, and were the highest in the 1970s and lowest in the 1990s with an increasing trend for period 2002-2010. The trends of variation in annual ET0 in Guangxi were also analyzed. Out of the 25 stations, 3 stations in karst and 4 stations in non-karst areas had significant decrease in trend; then 2 stations in karst and 1 station in non-karst areas showed significant increase in trend, and the other stations had no significant trends. Analysis of the relationship between ET0 and meteorological factors showed that sunshine duration, wind speed and average temperature were the main meteorological factors driving ET0 in non-karst areas. Relative humidity influenced annual ET0 by interacting with other meteorological factors in karst areas. Seasonally, sunshine duration and average temperature had the highest impact on ET0, and both were positively related with ET0. Furthermore, the indirect effect of the coefficient between wind speed and ET0 was negative for karst areas and positive for non-karst areas in winter and spring. Differences in geographical location and topography were the main reasons for the differences in ET0 between karst and non-karst areas. Therefore, understanding the trend of change and the reasons for the change in ET0 in different regions was a necessary measure for analysis of ecological water requirement.

     

/

返回文章
返回