Effects of Soil Nutrients on Crop Growth in Organic Farming Systems

Dear Colleagues,

Several decades of progress in conventional agriculture driven by green revolution technologies have led to global problems within all living organisms because of the excessive use of agrochemicals. The Intergovernmental Panel of Climate Change (IPCC) has noted that the currently practiced agriculture accounts for about 20% of the anthropogenic greenhouse effect, producing about 50% and 70% of anthropogenic methane and nitrogen oxide emissions, respectively, which in turn creates negative feedback effects on soil quality.

A sustainable solution to these problems is presented as organic agriculture defined by the FAO as a “holistic production management system which promotes and enhances agro-ecosystem health, including biodiversity, biological cycles and soil biological activity.” Organic farming has emerged as the only answer to bring sustainability to agriculture. It advocates not only for stopping the use of pesticides, but also focuses on creating a balance of a microenvironment-suitable soil for the health and growth of soil microflora and crops. As a rule of thumb, organic farming is providing plants with a balanced food supply by feeding the soil microflora organic manure of different origins, from farmyard manure to biogas digestate. Application of soil amendments should change the rhizosphere environment by affecting many properties of soil such as porosity, aeration, temperature and water holding capacity, as well as soil microflora.

Understanding that excessive use of chemical fertilizers without organic supplements not only pollutes the soil, but also deteriorates the surrounding environment is the premise to desisting mineral fertilizer use in organic farming. There are strong pieces of evidence that lower inputs of nutrients in organic farming do not reflect in a lower crop yield, maintaining good conditions for effective of biological processes.

Four decades of theoretical basis development, as well as the practice of organic farming have brought a lot of questions and doubts. As a result, some benefits of this type of soil management have been questioned.

First, there is a raise in environmental cost of organic products because more agricultural land must be used to produce the same volume of food. It can accelerate deforestation on a global scale, which can lead to a reduction in carbon storage capacity. According to numerous research, wide application of industrial and municipal wastes in the form of soil amendments can directly affect the quality of soil by increasing soil acidity, creating the risk of introducing pollutants called emerging pollutants (pharmaceutics, food additives, natural or synthetic hormones and other substances of persistent organic pollutants nature). Various problems relating the use of organic soil amendments are connected with chemical forms of essential nutrients. There are two contrasting views: according to some opinions, minerals “locked” in organic substances are not available to the roots of crops. For example, under the conditions of a high content of the total fraction of phosphorus in soil, plants suffer from P-deficiency because the polyphosphates present in sewage sludge are not available. A contrary opinion is that under conditions of microorganism abundance, soil organic matter cycles of nutrient turnover are fast and making minerals rapidly accessible for crops. The progress in studies focused on the role of mycorrhizas in agro-ecosystems can lead to understanding the nature of nutrient cycles in soil within the organic agriculture system.

Bearing in mind that both conventional and organic agriculture systems are turned toward the same aim—obtaining the maximal possible yield that it is accompanied by mineral nutrient uptake—the main area of focus of this Special Issue is presenting results of research works concentrated on the balance of soil nutrients in organic agriculture systems. Publications presenting the effects of organic amendment application in organic agricultural systems on the level of soil nutrients are welcome and we are awaiting manuscripts showing the effects of long-term soil management in organic agriculture systems.

Dr. Andrzej Klasa
Prof. Dr. Jadwiga Stanek-Tarkowska
Dr. Małgorzata Szostek
Dr. Magdalena Dębicka
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Plants is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• soil management
• agriculture systems
• soil science
• environmental chemistry
• soil nutrients
• agro-ecosystem
• soil nutrients
• crop growth
• organic farming systems