Fertilization is a key factor for sustaining productivity in agroecosystems. A long-term experiment in cambisol following periodical application of several types of fertilization has been running at the experimental site since 1954. In this study, we determined the impact of applied inorganic and/or organic fertilizers on the activity of soil enzymes and on the structure of microorganisms at depths of 0–30 cm and 30–60 cm. Single-factor comparison showed that use of inorganic and/or organic fertilizer had an insignificant effect on the activities of soil enzymes (at depths 0–30 cm and 30–60 cm) and also on the structure of microbial communities at both depths studied. Only soil respirations exhibited stimulation by combined fertilization. The results, irrespective of sampling depth (0–60 cm), showed that application of combined organic and inorganic fertilization stimulated the activity of glucosidases and use of inorganic fertilizer inhibited the activity of arylsulphatases. Respirations were stimulated by application of organic fertilizer and combined fertilization. Nevertheless, principal component analyses, which calculate with multidimensional data, revealed differences in samples treated by sole mineral fertilizer compared to other variants, especially in the lower layer. In general, our results indicate that use of combined fertilization may improve biological characteristics in deeper parts of soil profile and possibly increase biological activity in agroecosystems.
DUNDEK, P., HOLÍK, L., ROHLÍK, T., VRANOVÁ, V., REJŠEK, K., FORMÁNEK, P.: Methods of plant root exudates analysis: a review. Acta univ. agric. et silvic. Mendel. Brun., 2011, LIX, No. 3, pp. 241-246 The aim of this review is to summarise current knowledge on methods being used to determine individual compounds and properties of water-soluble plant root exudates. These compounds include amino acids, organic acids and simple sugars, as well as polysaccharides, proteins and organic substances. Qualitative composition of water-soluble root exudates and exudation rate are commonly measured with the aim of consequent synthetic preparation of plant root exudates to be supplied to soil to create artifi cial rhizosphere for diff erent experimental purposes. Root exudates collection usually requires consequent fi ltration or centrifugation to remove solids, root detritus and microbial cell debris, and consequent concentration using an evaporator, lyophilizator or ultrafi ltration. Methods used for analysis of total groups of compounds (total proteins and total carbohydrates) and total organic carbon are simple. On the other hand, HPLC or GS/MS are commonly used to analyse individual low molecular weight organic molecules (sugars, organic acids and amino acids) with separation using diff erent columns. Other properties such as pH, conductivity or activity of diff erent enzymes as well as gel electrophoresis of proteins are sometimes assessed. All of these methods are discussed in this work. amino acids, HPLC, GC/MS, organic acids, root exudates, sugars Substances released by healthy and intact roots into the environment are collectively designated as root exudates. These substances aff ect the composition of microbial community in immediate proximity of plant roots and processes taking place in rhizosphere. Many compounds are released by plant roots, including inorganic ions and substances,
Diurnal variations in streamflow are becoming acknowledged as a way of analysing how changing climatic conditions and land use affects watersheds but also as a way to understand watersheds as a whole. Yet not many studies from uplands below 900 mm mean annual precipitation zone are available from European countries. During the 2012 growing season, a sampling campaign took place in an upland forested micro‐watershed, Czech Republic (65 ha). Tree sap flow, rainfall and temperature were measured continuously, while streamflow at the discharge point and soil moisture were estimated from short‐term measurements. Short precipitation‐free periods lasting several days were identified for evaluation of trends in diurnal dynamics of both sap flow and streamflow. The results demonstrated that during these periods, the main factor altering streamflow was almost exclusively tree sap flow. A decrease in streamflow was observed during the day and an increase at night. The decline in sap flow after sunset was accompanied by a continuous increase in streamflow throughout the night up to its initial maximum in the morning. The amplitude in diurnal variations reached 18%. The observed time lag between the diurnal variations of sap flow and streamflow was approximately 2 h. Relatively low changes in diurnal dynamics of streamflow pointed out a strong regulatory role of the forest in buffering water discharge from the catchment. Copyright © 2015 John Wiley & Sons, Ltd.
This work was aimed to test the effect of selected amino acid enantiomers on activity of casein-protease and acid phosphomonoesterase in soil. Casein-protease was selected due to its key role in nitrogen mineralization and acid phosphomonoesterase due to its importance in soil organic P mineralization. The results showed that 5 mg of L- and D-glutamic acid added to fresh soil from Ah horizon of a moderately mown mountain meadow significantly (P < 0.05) decreased casein-protease activity, whereas alanine enantiomers slightly increased activity of this enzyme. Testing the effect of cystine on activity of acid phosphomonoesterase in soil showed slight increase of this activity after application of 3.2 mg L- or D-cystine to fresh soil (equivalent to 8 mg to dry soil).
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.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.