The paper summarizes the results of wind velocity measurement in different distances from windbreak in combination with optical porosity (OP) determination in different periods. Experimental data were obtained by direct measurement of wind speed and OP analyses of images of four windbreaks in Southern Moravia (part of Czech Republic). Wind speed at 2 m above the soil surface in a defined distance from windbreak had been measured since 2006. Thirty images of different phenological stages of selected windbreaks from 2006 to 2010 were analyzed. Windward or leeward images were converted into black and white spectrum. All available measurements were used for a map creation. The highest values of OP (up to 50%) are achieved in non-vegetation period. Due to the high OP variability in height of terminal tree branches "OP reduced" was also assessed (just squares to 2/3 height of windbreaks were evaluated). The wind speed reduction on the leeward side relatively strongly correlated with OP value. The highest correlation was found out when the wind speed measurement at 50 m on leeward side was used. The dependence decreases with increasing distance. Full foliage in summer (10% OP) reduces a wind speed about 60% at 50 m and about 30% at 150 m on the leeward. These values for non-foliaged windbreaks decrease to 80 and 90%. Maximum distance of windbreak effect on wind speed reduction was found out by the extrapolation of the curves constructed using the regression equation of wind speed reduction in dependence on OP and different distances from the windbreak. Regardless of OP value, the reduction effect disappears at a distance of 250 m. The quietest zone of evaluated windbreak with an average height of windbreaks 15-18 m was detected in the area about four times the height (4H). The effect of windbreaks decreases with increasing porosity.
Podhrázská J., Kučera J., Karásek P., Konečná J. (2015): Land degradation by erosion and its economic consequences for the region of South Moravia (Czech Republic). Soil & Water Res., 10: 105-113.The quality of agricultural land fund in the Czech Republic is assessed via a valuation system based on the ecological-productive land evaluation. This system was established in the 1960-1980s after a complex survey of agricultural land. It provided integral information on the agricultural land quality and on the price of agricultural land parcels derived from their productive capacity. Starting from the 1990s, evidence in the database of Evaluated Soil-Ecological Units (ESEU) has been regularly updated. Intensive cultivation of wide-spaced crops, namely in extended, largely sloped land parcels, has resulted in degradation of land characteristics by the effects of erosion. The ESEU updating makes it possible to detect these changes and their quantification by differences in land price. This approach was applied to evaluate the economic impacts of erosion at two model localities in intensively exploited agricultural areas, in the region of the most productive soils of the Czech Republic. We compared the price per 1 m 2 of land according to the land characteristics determined by the first land valuation with the current soil price based on the ESEU update. We also compared changes in the land characteristics.In the GIS environment, we established the mean long-term soil loss by erosion based on the original ESEU and compared it with the calculated soil loss based on the updated ESEU. The calculation method used was in accordance with the valid methodology for erosion calculation in the Czech Republic.
The paper is focused on the current status of land consolidation in Czechia. The survey is based on a questionnaire distributed electronically to municipalities and related subjects (agricultural organizations, farmers) in areas where the land consolidation has been completed, is in progress, or is under preparation. Small farmers and municipality representatives perceive the land consolidation as a measure facilitating permeability of the landscape and protection from erosion and/or from flooding. Land consolidation is important for companies in clarification of the land ownerships and as a remedy for the landscape needs. About half of the respondents believe that the measures have rather brought benefits, whereas 41% of respondents mainly highlight problems. The negative side of the land consolidation is mostly seen in the time delays and demanding administration; agribusinesses also point out complications with land management. Nevertheless, 75% of small farmers and municipalities and 62% of agribusinesses are interested in land consolidation. The main differences between small farmers and large companies consist in their attitude to reduction of the acreage of large plots and their division by common facilities.
The contribution presents the method of evaluation of rural landscape development in Hustopeče microregion by means of the analysis of landscape structure. Based on the computation of the values of landscape ecological indexes, development and typical and specific features in selected time horizons are interpreted. The time of the stable cadastre mapping (1825) was chosen as the initial period, other periods were the actual situation at present (2006) and the time between these two periods (the sixties of the 20 th century). It is an agricultural landscape in southern Moravia used for intensive farming. Analysis results illustrate long-term continuing landscape utilization for agricultural production. All evaluative indexes indicate reduction of number of patches and edge effect, enlarging of patch area and, consequently, increasing of geometrical extent and coarse-grained landscape pattern.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.