SELECTED SOIL PROPERTIES UNDER DIFFERENT TYPES OF MANAGEMENT

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1 SELECTED SOIL PROPERTIES UNDER DIFFERENT TYPES OF MANAGEMENT EVA HORAKOVA, LUBICA POSPISILOVA, VITEZSLAV VLCEK Department of Agrochemistry, Soil Science, Microbiology and Plant Nutrition, Mendel University in Brno, Zemedelska 1, Brno CZECH REPUBLIC Abstract: Basic soil properties such as porosity, soil reaction and humic substances content and quality were evaluated in Haplic Luvisol (Uhřice, Czech Republic) after conversion of ploughing soil into permanent grassland and forest. Soil porosity was calculated from physical cores. Soil reaction was measured by potentiometric method. Humic substances content was determined by short fractionation method. Generally, Haplic Luvisol (arable soil) was assessed as a high productive agriculture soil with good porosity, good humus content and quality, loamy textured, with weakly acid reaction, and high in nutrients content. Under different management systems all of studied properties have gradually changed. Three of permanent grassland showed increasing of total organic carbon and humic substances content, which means potential for organic carbon accumulation increased. On the other hand there are some negative consequences of intensive soil exploitation such as pedocompation, decreasing of porosity and acidification after conversion. Statistically significant differences were found between arable soil and forest three after conversion. Key Words: organic matter, porosity, soil reaction, Haplic Luvisol, land-use change INTRODUCTION Content and quality of soil organic matter is a very important factor of sustainable agriculture. Loss of humus leads to decreasing of crop yields and consequently to the soil degradation. Land-use management can enhance soil organic matter by optimal crop rotation, organic matter addition, and optimal fertilization and tillage systems, or by conversion into permanent grassland (Banwart et al. 2015, Guimarães et al. 2013). According to Doran and Parkin (1994) and Sáňka and Materna (2004) healthy soil is defined as a soil, which is able to fulfil all of its functions (e.g. biomass production and its safety, filtration and accumulation functions, transformation and hygienic functions). Parameters of soil quality/health are usually divided into chemical physical and biological (Doran and Parkin 1994, Pospíšilová and Vlček 2015). The most important indicators of good soil chemical properties is appropriate soil reaction, buffering capacity, high cation exchange capacity and stable soil colloidal complex. Soil reaction directly influence soil sorption capacity, plant growth and nutrients regime, and others physical and biological soil properties (Thomas 1996). As quoted Swift (1996) the main components of humic substances (HS) are fulvic acids (FA) and humic acids (HA). Because of relatively long period of their decomposition their ratio (HA/FA) is regarded as an important factor of soil quality/health. Healthy soils have also high porosity, appropriate structure, water holding capacity, and are not compacted (Pospíšilová and Vlček 2015). Soil porosity is closely connected with water regime, soil texture, structure, and directly influence soil chemical and biological properties. Porosity limit for loamy soil is 45 % (Lhotský 2000). All of these properties are influenced by intensive agriculture and by land-use management. Biocorridors play an important role in the landscape, because of elimination of soil erosion and improving life condition for animals. Changes of soil properties after biocorridors construction are not well studied (Horáková 2017). This study is focused on the effect of biocorridors onto selected soil chemical and physical properties. Main aim is to show how man activities and land-use changes in positive and negative ways affecting soil properties. 59

2 MATERIAL AND METHODS Study was localized in biocorridor Uhřice (Kroměříž region, Czech Republic). Monitoring was carried out during Soil properties were compared on arable soil, and after its conversion into forest soil and permanent grassland. Following soil properties were observed: texture, soil reaction, conductivity, humus content and quality, nutrient content, hydrophysical properties, and penetrometric soil resistance. In this paper are estimated only selected parameters soil reaction, humic substances content and quality and porosity. Figure 1 Locality Uhřice young forest (photo: Eva Horáková) Haplic Luvisol (locality Uhřice) belongs to the crop growing area. Average annual temperature is 8.5 C. Average annual precipitation is 650 mm. Soil was sampled twice a year (spring and autumn) during in the depth 0 30cm. In Figure 1 is illustrated view on the locality after conversion into forest soil. Basic soil properties were determine by standard method. Soil reaction was determined by potentiometric method in distilled water and in 1M KCl solution (1:2.5). Total porosity was calculated from physical cores (average from 3 replications, in the depth 0 30 cm). Total organic carbon content (TOC) was determined by oxidimetric titration method (Nelson and Sommers 1996). Fractional composition of humus was determined according to Kononova and Beltchikova method (1963). Detailed method s descriptions is given in Pospíšilová et al. (2016). HA/FA ratio was calculated from data of humus fractionation. Humification degree was calculated as a ratio of HS/TOC content multiply by 100. One way ANOVA analysis and t-test were used for statistical data evaluation. RESULTS AND DISCUSSION Studied soil was loamy textured, with good porosity, weakly acid, with middle content and low quality of HS. Changes of total porosity after land-use management changing is given in Figure 2. Figure 2. Average values of total soil porosity (P, %) 60

3 Obtained porosity results showed that after conversion in some cases total porosity was lower than the limit (45 %) for agricultural soils. Low porosity and pedocompaction during first year of conversion into forest could be explain by biocorridor construction and using of machinery. We can also conclude that permanent grassland soil (2016) is much more compacted to compare with arable soil. On the other hand, total porosity in arable soil is less than 50 %, which is very close to limit values (45 %) for agricultural soils. It was recommended to improve soil structure and increase soil porosity by application of organic fertilizers. Figure 3 Average content of humic substances (HS, mg.0.1/kg) Statistically significant difference in porosity between variants were not found. Humic substances content during studied period is given in Figure 3. Prevalence of FA was determined, which indicate low quality of HS. HA/FA ratio was less than 1, which confirms low quality of HS. Humification degree was middle (30 %). Conversion directly influence HS content. Statistically significant differences were found between arable soil and forest three after conversion (LSD = 0.220), see Table 1. No differences were found between arable soil and permanent grassland three year after conversion, but we can say that there is a tendency of increasing of HS amount. Table 1 Statistically significant differences in humic substances content Source No Sum Average Variance HS (mg/0.1kg; arable soil) HS (mg/0.1kg; forest) Source of variability SS Difference MS F P F crit Between sources All sources Total LSD Legend: one way ANOVA analysis, Fcrit = Results of exchangeable soil reaction is given in Figure 4. Decreasing of soil reaction and increasing of soil acidification is a result of intensive agriculture. Haplic Luvisol after land-use conversion should be later carefully observed. Liming was advised for improving soil reaction in all types of land-use. 61

4 Figure 4 Average values of exchangable soil reaction (ph/kcl) The results are taken from the diploma thesis of Eva Horáková. Other authors do not mention this locality. CONCLUSION Different type of land-use directly influence content and quality of humic substances, soil reaction and porosity. Statistically significant increasing of humic substances under forest soil, mainly fulvic acids, was documented. Higher organic carbon accumulation potential is expected in forest soil and under permanent grassland, but the results of three year s experiment were not statistically significant. With respect to the soil type monitoring of soil physical and chemical properties is recommended. Further it is suggested to control porosity, soil reaction, humic substances content and quality and increasing of liming doses. ACKNOWLEDGEMENTS Financial support from the National Agricultural Agency project QJ , and OP VaVpl CZ.1.05/4.1.00/ project Mendel University in Brno is highly acknowledged. REFERENCES Banwart, A.S., Noellemeyer, E., Milne, E The Global Challenge for Soil Carbon. In Soil Carbon - Science, Management and Policy for Multiple benefits. The University of Sheffield, Sheffield, UK: 71: Doran, J.W., Parkin, T.B Defining and assessing soil quality. In Defining soil quality for sustainable environment. Madison, Wisconsin, USA: Soil Science Society of America and American Society of Agronomy, pp Guimarães, D.V., Gonzaga, M.I.S., Silva, T.O., Silva, T.L., Dias, N.S., Matias, M.I.S Soil organic matter pools and carbon fractions in soil under different land uses. Soil & Tillage Research, 126: Horáková, E Monitoring půdních poměrů v biokoridoru Uhřice. Diplomová práce. Mendel University in Brno. Kononova, M.M., Belchikova, N.P Organiceskoje vescestvo pocvy. Moscow, AN SSSR, pp Lhotský, J Zhutňování půd a opatření proti němu: (studijní zpráva). ÚZPI Praha. Rostlinná výroba. 62

5 Nelson, D.W., Sommers, L.E Total carbon, organic carbon and organic matter. In Methods of soil analysis. Part 3. Chemical methods. Madison: Soil Science Society of America, pp Pospíšilová, L., Vlček, V Chemické, biologické a fyzikální ukazatele kvality/zdraví půdy. 1. vyd., Brno: Mendelova univerzita v Brně. Pospíšilová, L., Vlček, V., Hybler, V., Hábová, M., Jandák, J Standardní analytické metody a kritéria hodnocení fyzikálních, agrochemických, biologických a hygienických parametrů půd. 1. vyd., Brno: Mendelova univerzita v Brně. Thomas, G.W., Soil ph and soil acidity. In Methods of soil analysis. Part 3. Chemical methods. Soil Science Society of America, pp Sáňka, M., Materna, J Indikátory kvality zemědělských a lesních půd ČR. Praha: Ministerstvo životního prostředí. Swift, R.S Macromolecular properties of soil humic substances: fact, fiction, and opinion. Soil Science, 164(11):