Balázs Madarász

Conservation Agriculture in Europe

Abstract The adoption of Conservation Agriculture (CA) in Europe varies according to the ecological regions of the continent. Although Europe is behind other countries in adoption of CA, the indicators for future progress are encouraging. The area where CA is applied is growing rapidly because of increasing environmental awareness, including soil protection, and because of the need to reduce production costs. The European Conservation Agriculture Federation (ECAF) plays an important role in the adoption and dissemination of CA practices, and in discussions involving CA and the EU Common Agricultural Policy (CAP) reform. Yield performance and stability, operating costs, environmental policies and programs of the Common Agricultural Policy (CAP), and climate change will likely be the major driving forces defining the direction and for the extension of CA in Europe. The role of agriculture in climate change mitigation in the EU is discussed in the paper.

Redistribution of Soil Organic Carbon Triggered by Erosion at Field Scale Under Subhumid Climate, Hungary

Abstract Soil organic carbon (SOC) has primary importance in terms of soil physics, soil fertility and even of climate change control. One hundred soil samples were taken from an intensively cultivated Cambisol to quantify SOC redistribution triggered by soil erosion under a subhumid climate, by the simultaneous application of diffuse reflectance (240–1 900 nm) and traditional physico-chemical methods. The representative sample points were collected from the solum along the slopes at the depth of 20–300 cm with a mean SOC content of 12 g kg−1. Hierarchical cluster analyses were performed based on the determined SOC results. The spatial pattern of the groups created were similar, and even though the classifications were not the same, diffuse reflectance had proven to be a suitable method for soil/sediment classification even within a given arable field. Both organic and inorganic carbon distributions were found to be a proper tool for estimations of past soil erosion processes. The SOC enrichment was found on two sedimentary spots with different geomorphological positions. Soil organic matter composition also differed between the two spots due to selective deposition of the delivered organic matter. The components with low-molecular-weight reached the bottom of the slope where they could leach into the profile, while the more polymerised organic matter compositions were delivered and deposited even before on a higher segment of the slope in an aggregated form. This spatial difference appeared below the uppermost tilled soil layer as well, referring the lower efficiency of conventional ploughing tillage in soil spatial homogenisation.

Conservation tillage vs. conventional tillage: long-term effects on yields in continental, sub-humid Central Europe, Hungary

The present study reports novel data concerning Conservation Tillage (CT) in the continental sub-humid climate zone in Central Europe (Hungary), an area which has been mostly neglected in the course of previous CT studies. The results of a 10-year (2003–2013) comparative study of mouldboard ploughing tillage (PT) and CT (no inversion, using a reduced number of tillage operations and leaving min. 30% crop residues on the soil surface) types are reported. Our extensive monitoring system has provided new and detailed information concerning technologies and yields both from the first, transitional period and, over the following years, of adapted technology. Our results suggest that tillage type was a more important factor in the question of yields than either the highly variable climate of the studied years, or the diverse slope conditions of the plots. During the first three years of technological changeover to CT (2003–2006), a decrease of 8.7% was measured, respective to PT. However, the next seven years (2007–2013) brought a 12.7% increase of CT yields. Our study revealed key factors in the initial reduction of crops during the technological change, and may accordingly serve as a guideline for the shortening or avoidance of decline in the transitional period.

Characterization of Soil Organic Substances by UV-Vis Spectrophotometry in Some Soils of Hungary

UV-Vis spectrometry methods are widely used to characterize soil organic matter, especially humic substances from different extracts of soils. Our aims were to investigate organic characteristics of soils, as part of a project focusing on relationships between solute mineral components and organic matter quality. The study was performed using UV-Vis spectrophotometry on six Hungarian soils. For the characterization of humic substances we used several visible and UV methods. Humic materials were extracted from soils using a variety of extractants. We found that a decrease in pH and an increase in dissolved electrolyte concentration supported coagulation in preferance to dissolution in almost every case. The highest absorbance values was given by extractants which contained sodium-pyrophosphate. In our experience double extraction methods (ENaF/ENaOH according to Hargitai, A talaj szerves anyaganak meghatarozasa es jellemzese. In: Buzas I (ed) Talaj- es agrokemiai vizsgalati modszerkonyv II. Mezőgazdasagi Kiado, Budapest, 1988, E400NaOH+Na4P2O7/E400PBS) and E4/E6 are suitable for analysing humic substances. Comparing these three visible methods there are only slight differences between them. The results do not show strong correlation between visible and UV methods as these techniques analyse different properties of soil humic substances.

Soil Organic Carbon Redistribution by Erosion on Arable Fields

Colloids are thought to move easily, consequently both mineral and organic colloids are overrepresented in runoff and soil loss, which causes selective erosion. Soil loss compound is a function of scale. The enrichment of soil organic carbon (SOC) and of the clay fraction in soil loss was studied at two sites in Hungary. A rainfall simulator was applied to describe selective erosion at micro (<1 m2) and plot (2 × 6 m) scale. At field scale, soil loss samples were taken from 25 to 50 m intensively tilled runoff plots to assess SOC losses. At plot scale, selective erosion takes place as redistribution within the plot with crust formation. Thin sections demonstrate the horizontal structure of the particles on the surface covered by SOC and clay colloids. The rate of SOC enrichment is inversely proportional to the amount of soil loss. Enrichment is significant in the settled (coarse) part of soil loss, while – in contrast to the plot scale results – there is no SOC surplus in the suspended part. SOC components of high molecular weight seem to be increasingly vulnerable to erosion and they are overrepresented in soil loss. Because of their high stability carbon sequestration occurs in the buried horizons.

Facing to real sustainability—conservation agriculturalpractices around the world

This special issue of Environmental Science and Pollution Research highlights selected papers presented at the International Conference on Conservation Agriculture and Sustainable Land Use (CASLU), held between 31 May and 2 June 2016 in Budapest, Hungary. It is evident that the present development of the activities of human society is unsustainable and without radical changes, it would lead to the depletion of natural resources. As a consequence of rapid population growth, food demand also increases very fast requiring a more intensive agriculture and the use of low quality land for agricultural purposes. Conventional agricultural practices endanger the fertility of huge areas in the world. Previous research has demonstrated that Conservation Agriculture (CA) could be an effective solution to the problems caused by conventional agriculture, such as soil erosion, destruction of soil structure, reduction of permeability, greenhouse gas emissions, enormous energy consumption, contamination of surface and subsurface water resources and the decrease of biodiversity. As a result of quick knowledge transfer, CA is employed over 170 million ha today, while the estimated value in 1999 was only 45 million ha. The greatest extension and percentage values are in North and South America, South Africa, and Australia. Nowadays, CA is a widely known practice; however, its practical details and effectiveness hardly depend on local economic and environmental circumstances. Accordingly, most of the papers presented at the conference were case studies e contributing to the most up to date knowledge on CA. Bearing the idea of sustainability in mind, the meeting was organized as a Bsustainable conference^, i.e., minimizing the environmental stress in every respect. From Canada to Japan and from Norway to Australia, 102 researchers of 36 countries have presented the results of their recent studies. Altogether, 43 oral and 99 poster presentations were given in the following sections: Soil science and geomorphology in Conservation Agricultural Systems; Agroecological research in Conservation Agricultural Systems; Yields and economy; Climate change and Conservation Agricultural Systems; Conservation Agricultural Systems and the carbon cycle; Sustainability assessment of land use and cover change; Precision Agriculture in Conservation Agricultural Systems; Organic farming. Keynote presentations tried to summarize the holistic question of BWhere are we and what to do next?^. G. Govers emphasized the role of chemicals in his keynote talk that generated a highly exciting and relevant conversation about the necessity of pesticides and fertilizers if CA is applied under various environmental conditions. Quite a few presentations also highlighted the ambiguities and problems to face. The highest importance was dedicated to the climate change related questions that seemed to be the biggest challenge of CA and Sustainable Land Use. Participants agreed to analyze measurement data from the whole world in order to make the effect of climate change on CA predictable. Responsible editor: Philippe Garrigues