Modification of direct runoff in a small forest catchment of the Krajeńskie Lakeland as a result of the watercourse develop-ment

The field investigations were carried out in a small forest catchment situated in the area of the Krajenskie Lakeland, in the Lipka Forest District, the Biskupice Forest Range. The catchment covers the area of 182ha; 95% is covered by forests and 5% by arable land and meadows. The field measurements comprised a continuous recording of the course water levels at the Thompson’s overflow and weekly measurements of groundwater levels in ten wells. Construction development was introduced on the area of the watercourse during the conducted research: six damming devices (installations) constant weirs-were constructed there. The sums of precipitation and indices of high water stages were calculated on the basis of direct measurements. Daily evapotranspiration was calculated according to Konstantinow method, and next its monthly and annual sums were calculated. Changes in storage levels were calculated on the basis of the groundwater levels measurements. The hydrological year 2004/2005 is an average one considering the annual atmospheric precipitation sum, as well as mean annual air temperature; the values are in the adequate intervals of 90–100% of the multi-annual mean values. The annual outflow coefficient from the catchment in focus equals to 0.330. It confirms the necessity of developing the discussed watercourse in ...

Modification of direct runoff in a small forest catchment of the Krajeńskie Lakeland as a result of the watercourse development

The field investigations were carried out in a small forest catchment situated in the area of the Krajeńskie Lakeland, in the Lipka Forest District, the Biskupice Forest Range. The catchment covers the area of 182 ha; 95% is covered by forests and 5% by arable land and meadows. Field measurements comprised continuous recording of water level at the Thompson's weir and weekly measurements of groundwater levels in ten wells. Construction development was introduced in the area of the watercourse during the conducted research: six damming devices (installations) constant weirs - were constructed there. The annual outflow coefficient from the catchment equals to 0.330. It confirms the necessity of developing the discussed watercourse in order to create the so-called small retention. However, no significant influence was found of the development on the water balance components of the catchment. The influence of the watercourse bank development can be clearly described by conducting an analysis of direct runoff. 14 recorded large floods were subject to analysis; 6 prior to the development and 8 following it. Each of the waves was described by applying Nash's conceptual model. A constant number of 2 reservoirs in a cascade was assumed. Means of time-constants for high water ...

Result of the watercourse development in a small forest catchment on its retention capacity

The field investigations were carried out in a small forest catchment situated in the area of the Krajeńskie Lakeland, in the Lipka Forest District, the Biskupice Forest Range. The catchment covers the area of 182ha; 95% is covered by forests and 5% by arable land and meadows. The field measurements comprised a continuous recording of the course water levels at the Thompson’s overflow and weekly measurements of groundwater levels in ten wells. Construction development was introduced on the area of the watercourse during the conducted research: six damming devices (installations) constant weirs-were constructed there. The annual outflow coefficient from the catchment in focus equals to 0.330. It confirms the necessity of developing the discussed watercourse in order to create the so-called small retention. However, no significant influence was found of the development on the water balance components of the catchment. The influence of the watercourse bank development can be clearly described conducting an analysis of direct runoffs. 14 recorded high water waves were subject to analysis; 6 prior to the development and 8 following it. Each of the waves was described applying Nash’s conceptual model. A constant number of 2 reservoirs in a cascade was assumed. Means of time-constants for ...