Influences of forested watershed conditions on fluctuations in stream water temperature with special reference to watershed area and forest type
Influences of forested watershed conditions on fluctuations in stream water temperature with special reference to watershed area and forest type
复制标题
森林流域条件对溪流水温波动的影响，特别是流域面积和森林类型
DOI：
10.1007/s10201-008-0258-0
复制
发表时间：
2009
期刊：
影响因子：
1.6
通讯作者：
N. Ozaki
中科院分区：
文献类型：
--
作者：
L. Subehi;T. Fukushima;Y. Onda;S. Mizugaki;T. Gomi;T. Terajima;K. Kosugi;S. Hiramatsu;H. Kitahara;K. Kuraji;N. Ozaki
为了深入了解流域条件对河流水温波动的影响，我们使用均方根（Rms）和谐波（AA幅值，φ延迟时间）方法对1年的水温数据进行了统计分析。小流域（< 0.5 ha）、中流域（0.5-100 ha）和大流域（> 100 ha）的气温和水温（Ta和Tw）之间的延迟时间（天）平均值分别为4.53±0.82天、11.83±3.88天和4.45±1.52天。在中等坡度的中型流域，用Rms（RmsTw/RmsTa）和调和法（A−Tw/A−Ta）表示的溪流水温波动分别为0.37±0.09和0.56±0.14。这些值在坡度较小的较大流域中增加，包括被不同景观覆盖的5条大河流，其平均值分别为0.53±0.09和0.78±0.09，表明太阳辐射和传热过程的影响。在坡度梯度较高的较小流域中，这些值分别为 0.73 ± 0.02 和 0.87 ± 0.03，表明较短的通过时间会影响水温。就森林类型而言，管理不善的扁柏森林流域的这些值（0.45±0.04和0.73±0.07）大于阔叶林（0.34±0.04和0.51±0.12）和管理良好的扁柏林（0.33±0.04和0.51±0.07）。分水岭，表示不同比例的流路。
In order to gain insight into the effect of watershed conditions on fluctuations in stream water temperature, we statistically analyzed water temperature data for 1 year, using root mean square (Rms) and harmonic (AAmplitude,φdelay time) methods. The average values of delay time (days) between air and water temperatures (TaandTw) of small (< 0.5 ha), medium (0.5–100 ha) and large (> 100 ha) watersheds were 4.53 ± 0.82 days, 11.83 ± 3.88 days and 4.45 ± 1.52 days, respectively. Fluctuations in stream water temperature expressed by Rms (RmsTw/RmsTa) and harmonic methods (A−Tw/A−Ta) in the medium-sized watersheds with moderate slope gradients were 0.37 ± 0.09 and 0.56 ± 0.14, respectively. These values increased in the larger watersheds with low slope gradients, including five large rivers covered by various landscapes, with their averages of 0.53 ± 0.09 and 0.78 ± 0.09, respectively, indicating the influences of solar radiation and heat transfer processes. In the smaller watersheds with high slope gradients, these values were 0.73 ± 0.02 and 0.87 ± 0.03, respectively, suggesting that shorter passage time affected water temperatures. With respect to forest type, these values at badly managed hinoki forest watersheds (0.45 ± 0.04 and 0.73 ± 0.07) were larger than those at broadleaf forest (0.34 ± 0.04 and 0.51 ± 0.12) and well-managed hinoki forest (0.33 ± 0.04 and 0.51 ± 0.07) watersheds, indicating different proportions of flow paths.