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 ...
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 ...
Small water reservoirs are principal elements of small retention. Reservoir built in Zarzeczany village (Gródek commune, Podlasie region) in 2000 is the example of such object. It is localized in wide, wet, and flat valley. Water to the reservoir is supplied by melioration ditch receiving waters from catchment runoff and, during summer droughts, from river Gleniówka. An apparent effect of surface runoff on water quality was observed in the reservoir. It was found that after the rainfall, values of many tested water parameters (color, turbidity, phosphates, COD-Mn, ammonia, nitrates) were increased. The concentration increase of indices responsible for water contamination with organic compounds at simultaneous relatively high color indicated the humus origin of that contamination. ...
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 ...
The paper present the detailed assessment of water retention possibility in the lakes situated in the Struga Dormowska River. These activities were important to increase satisfy water needs warranty of fish ponds. Struga Dormowska is the third rank river, the left tributary of the Warta River. The area of the catchment amounts 57.2 km2. The catchment has an agricul-ture-forest character and high lake density. Struga Dormowska flow through twelve lakes, which have an area of 240 ha. The area of each lake range from 2 to 79.6 ha. The catchment has a very small water resources. Specific runoff of the catchment equals about 2 dm3.s-1.km-2, and runoff coefficient about 0.1. The researches reveal that increase of lakes water retention allows to obtain high amount of disposal water, that allows to increase water needs of the fish ponds warranty satisfy located in the middle and lower part of the river. The estimation was based on amplitudes of water level in the lakes, elevation-storage curves and inventory of hydraulic structures along the river. Damming of the water in the seven lakes from 0.2 to 0.3 m in natural water level oscillations allows to gain about 0.4 mln m3 water in the usable ...
In the study, it was pointed to a small utilisation of potential agricultural productivity in Poland (on average, around 62%), under the conditions of existing water deficiencies. Results of the study confirm that using new technologies and rational management, plant yields harvested can be higher than average ones in the region (in winter wheat growing by 14,7 dt•ha-1, i.e. by 37,1%) and be close to the potential yields. Higher crops growing intensity results in an improved water use efficiency.In water management aiming at increase of water resources, agricultural retention play an important role (so called "small retention"), which is made up of soil retention and landscape retention. Increasing the water retention by only 1% in the studied "Rów Wyskoć" mikrocatchment, in Wielkopolska region, would decrease the annual water discharge from this catchment by 4% and it would amount to 8.9% of the discharge during the vegetation period (IV-IX). Different agrotechnical measures of increasing soil retention were discussed as well as the effect of cropping pattern and nonagricultural elements on the water retention of the landscape were considered.
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A forest is the form of natural storage reservoir and it by this can be perceived as mainstay of small water retention. The prognoses of unfavourable climatic changes (growth of air temperatures, diminishing of precipitations, frequency increase of extreme weather phenomena) causing a necessity of compensations these the unfavourable phenomena by a technical and un-technical undertakings to increase water storage in forests. The building of devices of small retention has reason both: natural (i.a. assure in forest ecosystems biodiversity) and economic aspects. Indicatory cost water storage 1 m3 of water in objects of small retention is ten times smaller than in great storage reservoirs. Permission to building of objects of small retention is required for damming height 1,0 m or for every investment situated on protected areas. More than once its very increased the costs of investment. Therefore building a small objects is pragmatic, e.g. a cascade systems reservoirs. The building of objects damming and slowing outflow from catchments is focused to protection of the valuable natural habitats and it can be use full in strategy of protection of areas - may be the essential element Nature 2000 (e.g. forest bogs ecosystems, moist or flood plain forest). In Poland at ...
The paper contains information refers to the possibility of water retention in the lowland Jeziorka stream catchment. The Jeziorka stream is II order river, located entirely in the Oder valley in Lower Silesia, in the district of Środa Śląska. It is a right tributary of the Średzka Woda stream which flows into the Oder river in the region Malczyce. The characteristics of the catchment area, including its location, geological, soil and weather conditions is presented in the paper. Water resources of catchment and the groundwater depths are also described. The paper presents an inventory of existing small retention facilities in the analyzed catchment. Possibilities of water retention on the basis of the characteristics of the described area and after carefully reading the basic forms of retention is presented in the paper. Diagrams of practical use objects and conditions for water retention are described. Morphological structure of the Jeziorka catchment and analysis of source materials and topographic maps have found that the best form of water retention for this catchment is retention of riverbeds and river valleys. ...
