География и геология/3. Гидрология и водные ресурсы

Kyryliuk Olena and Kyryliuk Sergey, masters

Chernivtsi Yuriy Fedkovich National University, Ukraine

Hydromorphological conditions and basin planning of sustainable development of small rivers in the Upper Prut River basin

The studied basin systems are part of the Upper Prut in the Chernivtsi region (Table 1). Upper Prut Basin system is one of contrast to natural conditions and landscape structure area that leads to the activation of many natural processes. However, not many scientific researches are conducted on the basin system of Upper Prut with hydrological and river-bed sides have been insufficiently studied. Selected river-indicators are related to the Black Sea type of water treatment, the filling mixed with a predominance of rain. For each basin system there has been studied the features of the hydrological regime and the formation of hydromorphological characteristics. Studying of hydrological characteristics held by clarifying passport data in the field during the 2005-2011 years and analysis of hydrological yearbooks. Based on the analysis of some passport data, longitudinal profile, cartographic material there were selected homogeneous areas of channels (HAC) rivers: on the Gukiv - 5 HAC, on the Dereluy and Vyzhenka - 6 HAC in each. Description and analysis of hydromorphological characteristics of "flow-river-bed" was carried out on selected units.

Table 1

Some characteristics of Gukiv, Dereluy and Vyzhenka river

River basin	Localization	Watershed area, mi^2	Stream length, mi
Gukiv	Prut-Dniester interfluve	25,35	6,24
Dereluy	Precarpathian Trough	122,07	13,26
Vyzhenka	Mountain zone	43,68	11,31

For each homogeneous region it is made natural descriptions (the length; the absolute level, slope, valley bottom width and its shape; the bed shape characteristic, the high water mark, floodplain and channel, etc.) and anthropogenic component (riverbed rates, availability of coastal water protection strips zones, littering, discharges, intakes, sewage, calculated the transformation of river network). Changes in the structure and parameters of the drainage system functioning are the result of the display of transformation and degradation processes that are developing under the influence of natural and anthropogenic factors. The Gukiv river network structure undergones the following changes: 4 streams ceased to exist, however, the new six watercourses formed. Disappearance of the first order rivers in the upper basin due to logging within Chornivka forestry, at the place where the river originates. One of watercourses changed order from the first to the second. The disappearance of the middle reaches of watercourses mainly associated with dynamic household activities on the floodplain. In the river system of Dereluy it is seen the appearance of new permanent watercourses of the first order, which previously belonged to the temporary. However, it is also available the extinction of many streams of the first and the second order. The rate of main river also changed – it reduced from V to IV. Calculations show that the total number of streams of the 1st, 2nd, 3rd orders reduced. Such changes can be explained by transforming of the river system structure (transition of the second order streams to the first, the third – to the second, etc.). Many streams in Vyzhenka river network moved from the temporary to constant of the first order.

There were analysed anthropogenic activities in the basin system as a whole - anthropogenic transformation of landscapes, surveying dangers, nature use conflicts and environmental risks. Comparison of nature for modification of Gukiv, Dereluy and Vyzhenka basins showed that in Gukiv and Dereluy basins heavily transformed areas dominate - mostly the lands under settlements and arable land, the main effects of which for river channel are increasing the flow of sediment, silt, lateral erosion of pollutant substances, pollution and household debris, mechanical changes, changes in floodplain landscapes. In Vyzhenka basin there is different situation - more than 80% of the area is poorly converted, since there were established protected area and limited economic activity. Based on assessment of the current state of Gukiv, Dereluy and Vyzhenka basins there were indicated many environmental conflicts. Most conflicts in nature use are observed for agricultural and settlement types. The predominance of areas with high anthropogenic pressure is connected with intensive plowing, dedicated to the slope surface, medium and low with weak shared areas using as grasslands and natural pastures. One way to resolve such situation is to develop a system of nature rationalization, based on pre-planning through thematic maps generated to identify areas with intense environmental situation, and the development of river basin management plan.

For each river there were held 2 complexes of hydromorphological assessment - for Gukiv River in 2005 and 2011, for Dereluy and Vyzhenka - in 2006 and 2012. For a period of 6 years, there are some changes in the parameters of flow characteristics, of coast and coastal area, floodplains. Parameters remain unchanged in river channel, as in such brief period it is not observed a meandering change, type of river-bed and channel straightening. For river Gukiv one of the survey areas (SA) - SA 2 - changed status from "excellent" to "good". On Dereluy river 2 sites have changed the quality class from the "excellent" to "good". For Vyzhenka river similar changes occurred in SA 5. Such changes are related primarily with floods in 2008 and 2010 years. One of the drawbacks of such evaluation is that it does not involve the assessment of coastal protective strips availability, because according to that the greatest quality class would be "fair". Studying of the floodplain and river-bed complexes based on the Framework Water Directive.

On the studied territory there are following common anthropology landscapes: creating settlement landscape, agriculture, forestry, recreational activities, the creation and operation of linear industrial facilities. Measure of anthropology and indicators of environmental and economic balance change on selected areas. Totally analyzed and evaluated effect of six environmental risks of local floodplain system: change in water quality and development of placer mines as risk of water flow, landscapes anthropogeny as risk of landscape system and flood, flooding and destruction of the coast as the risk of social-ecological system.

According to the Draft of Law of Ukraine "About the Concept of Ukraine's transition to sustainable development" one of the priorities of regional development in relation to water resources is a further development of the basin approach to resource management, restoration of the natural regime of the small rivers and limitations the economic activities in the catchment area, especially in areas source and water protection zones. Solving all the problems related to planning of the territory and sustainable development requires appropriate scientific base and training of qualified personnel. Scientific knowledge should be provided in various forms, but the most important values have national databases that contain the minimum required hydrological information and data of resource use. We have identified factors that in our opinion are informative about the state of the basin system from position of its potential sustainable development (taking into account its natural element). To the main factors belong: the transformation of river network (the length and number of different order tributaries), anthropogenic elaborateness, environmental conflicts (by quantity, intense and dynamic factors), erosional danger, floodplain estimation (by type of use), manifestation of hydroecological dangers, hydromorphological assessment of river-bed and riparian vegetation (by class of quality), assessment of land use and the scrutiny of basins.

Based on the above characteristics Algorithm of ecological and hydromorphological assessment of river basin for sustainable development was established. Assessment of any basin territory is held on the base of relative points.

Adverse areas for sustainable development (less than 26 points) in accordance with the SWOT-analysis of geo-ecological problems and prerequisites of sustainable development are characterized by the virtual absence of strengths aspects and opportunities and the presence of weaknesses and threats. Transformation of the river network (by quantitative and by length) is moderate and intense. For elaborateness of area by man and machine, it is dominated high transformed and very high transformed territory. Environmental conflicts are characterized as stable and increscent by dynamics, high and very high by intense and 4-5 characteristics by the quantity (conflict with each other on a relatively small land area settlement, transport,

Gukiv basin system	Dereluy basin system		Vizhenka basin system
Fig.1. Interpretative maps for sustainable development

agricultural and recreational types of nature use). Erosional danger is medium and high. Floodplain area is mostly built, with hydraulic structures and it is modified. Speaking about hydroecological dangers, then on the territories there is increased and high risk of channel processes, resulting in washout of land, lost productivity and quality of wetlands, floodplains waterlogging, flooding and flooding localities active landslide and erosion is high risk breakthrough pond dams etc. In hydromorphological ratio prevail poor and very poor quality classes. In land use prominent place is stipulated by cultivated land and built-up areas.

Areas of moderate sustainable development (27-41 points). In the transformation, erosion and sediment channel network dominate weakly and medium transformed area. Results of human activities are converted and medium converted

areas. Nature use conflicts demonstrate themselves as unstable, weak and 3-4- componented. Erosion danger shows itself as a minimum and weak. Floodplain is mainly under agricultural lands. Displaying of channel processes is characterized as mild and moderately dangerous. Among hydromorphological indicators there are good and satisfactory quality classes. In land use main place is occupied by other types of vegetation, such as meadow, grasses and ruderal associations and a small amount of arable land.

Areas favorable for sustainable development (more than 42 points) have many strong points on the internal environment and opportunities for outside. Weaknesses of internal and threats of external environment are almost absent. Transformation processes in river networks are little or no change compared to older years. Here the available wanly transformed human territory. Among the conflicts in environmental management there are decaying (the dynamics), weak (in intensity) and 2-3 - component (by number). Demonstration of erosion processes in a network of temporary and permanent watercourses is absent or minimal. Floodplain is in its natural state. Danger of demonstration fluvial processes is absent or weak. Investigated hydromorphological parameters are related to the excellent and good quality classes. In land use predominantly indigenous vegetation takes place.