This study is focused on the northwestern part of Gansu Province, namely the Hexi Corridor. The aim is to address the question of whether any trend in the annual and monthly series of temperature and precipitation dur...This study is focused on the northwestern part of Gansu Province, namely the Hexi Corridor. The aim is to address the question of whether any trend in the annual and monthly series of temperature and precipitation during the period 1955-2011 appears at the scale of this region. The temperature and precipitation variation and abrupt change were examined by means of linear regression, five-year moving average, non-parameter Mann-Kendall test, accumulated variance analysis and Pettitt test method. Conclusions provide evidence of warming and wetting across the Hexi Corridor. The mean annual temperature in Hexi Corridor increased significantly in recent 57 years, and the increasing rate was 0.27℃/10a. The abrupt change phenomenon of the annual temperature was detected mainly in 1986. The seasonal average temperature in this region exhibited an evident upward trend and the uptrend rate for the standard value of winter temperature indicated the largerst of four seasons. The annual precipitation in the Hexi Corridor area displayed an obviously increasing trend and the uptrend rate was 3.95 mm/10a. However, the annual precipitation in each basin of the Hexi Corridor area did not passed the significance test. The rainy season precipitation fluctuating as same as the annual one presented insignificant uptrend. No consistent abrupt change was detected in precipitation in this study area, but the rainy season precipitation abrupt change was mainly observed in 1968.展开更多
城市集中式生活饮用水水源地水质状况直接影响到人们的身体健康,探究其水质现状和变化趋势对水源地保护具有重要意义。在分析珠江三角洲城市群水源地水质现状的基础上,结合Pettitt Mann Whitney变异点分析法、Mann-Kendall检验法和Sen...城市集中式生活饮用水水源地水质状况直接影响到人们的身体健康,探究其水质现状和变化趋势对水源地保护具有重要意义。在分析珠江三角洲城市群水源地水质现状的基础上,结合Pettitt Mann Whitney变异点分析法、Mann-Kendall检验法和Sen斜率估计定性定量判断水质的时空变化趋势。结果表明,广东省水源地水质现状整体较好,仅4个水源地水质均值大于40,但水质指数较小的水源地略呈恶化趋势;水源地水质整体上在2010~2012年发生显著变化;除水质指数较大的水源地外,突变前水质指数均值整体上小于突变后,但突变后的水质指数均值均小于40;突变点前水质波动幅度较大,而突变点后水质趋向稳定。展开更多
基金National Key Technology R&D Programme of China,No.2012CB955304
文摘This study is focused on the northwestern part of Gansu Province, namely the Hexi Corridor. The aim is to address the question of whether any trend in the annual and monthly series of temperature and precipitation during the period 1955-2011 appears at the scale of this region. The temperature and precipitation variation and abrupt change were examined by means of linear regression, five-year moving average, non-parameter Mann-Kendall test, accumulated variance analysis and Pettitt test method. Conclusions provide evidence of warming and wetting across the Hexi Corridor. The mean annual temperature in Hexi Corridor increased significantly in recent 57 years, and the increasing rate was 0.27℃/10a. The abrupt change phenomenon of the annual temperature was detected mainly in 1986. The seasonal average temperature in this region exhibited an evident upward trend and the uptrend rate for the standard value of winter temperature indicated the largerst of four seasons. The annual precipitation in the Hexi Corridor area displayed an obviously increasing trend and the uptrend rate was 3.95 mm/10a. However, the annual precipitation in each basin of the Hexi Corridor area did not passed the significance test. The rainy season precipitation fluctuating as same as the annual one presented insignificant uptrend. No consistent abrupt change was detected in precipitation in this study area, but the rainy season precipitation abrupt change was mainly observed in 1968.
文摘城市集中式生活饮用水水源地水质状况直接影响到人们的身体健康,探究其水质现状和变化趋势对水源地保护具有重要意义。在分析珠江三角洲城市群水源地水质现状的基础上,结合Pettitt Mann Whitney变异点分析法、Mann-Kendall检验法和Sen斜率估计定性定量判断水质的时空变化趋势。结果表明,广东省水源地水质现状整体较好,仅4个水源地水质均值大于40,但水质指数较小的水源地略呈恶化趋势;水源地水质整体上在2010~2012年发生显著变化;除水质指数较大的水源地外,突变前水质指数均值整体上小于突变后,但突变后的水质指数均值均小于40;突变点前水质波动幅度较大,而突变点后水质趋向稳定。
