ROMANIAN SOIL RESOURCES - “HEALTHY SOILS FOR A

HEALTHY LIFE”

Mircea MIHALACHE, Leonard ILIE, Doru Ioan MARIN

University of Agronomic Sciences and Veterinary Medicine of Bucharest 59 M r ti Blvd., District 1, Postal Code 011464, Bucharest, Romania

Corresponding author email: mihalachemircea@yahoo.com

Abstract After nearly three years of intensive consultations, 2015 has been declared the International Year of Soils by the 68th UN General Assembly (A/RES/68/232). The International Years of Soil is to be a major platform for raising awareness of the importance of soils for food security and nutrition and essential eco-system functions. Key objectives of the International Years of Soil have been identified as follows: to create full awareness of all stakeholders about the fundamental roles of soils for human life; to achieve full recognition of the prominent contributions of soils to food security and nutrition, climate change adaptation and mitigation, essential ecosystem services, poverty alleviation and sustainable development; to promote effective policies and actions for the sustainable management and protection of soil resources; to sensitize decision-makers about the need for robust investment in sustainable soil management activities, to ensure healthy soils for different land users and population groups; to catalyze initiatives in connection with the Sustainable Development Goal process and Post-2015 agenda; to advocate rapid enhancement of capacities and systems for soil information collection and monitoring at all levels (global, regional and national) (http://www.fao.org/soils-2015). Applying a proper management of the recovery and conservation of soil resources is a major goal for every nation. The development of a country depends on the production potential of own soil resources. Soil degradation is a serious problem in Europe an also in Romania. It is caused or exacerbated by human activity such as inadequate agricultural and forestry practices, industrial activities, tourism, urban and industrial expansion etc. Soil Quality Monitoring in Romania revealed a number of problems concerning land use in Romania following the manifestation of one or more limiting factors such as: moisture deficit, salinization and alkalization, soil erosion, waterlogging, reduced organic matter content soil acidity, compaction, pollution, reduced edaphic volume etc. Key words: soil resources, soil health, degradation, monitoring. INTRODUCTION Soil health has been defined as "the continued capacity of the soil to function as a vital living system, within ecosystem and land-use boundaries, to sustain biological productivity, promote the quality of air and water environments, and maintain plant, animal, and human health". (Doran et al., 2002) The trend in soil health is the assumed change in the recent past, determined by two major pressures on the soil as they are influenced by soil management: • The physical pressures related to loss of soil

mass and structure; • the pressures on the long term chemical

well-being of the soil in terms of nutrient availability and the absence of toxicities built up in the soil.

This trend can be negative (degradation) if the soil management is not adequately counteract the (natural and management) pressures, but may also be positive and result in improvements when the applied soil management and conservation techniques and approaches are more than compensating soil deterioration. Healthy soil gives us clean air and water, bountiful crops and forests, productive rangeland, diverse wildlife, and beautiful landscapes. Soil does all this by performing five essential functions. Nutrient cycling - soil stores, moderates the release of, and cycles nutrients and other elements. During these biogeochemical processes, analogous to the water cycle, nutrients can be transformed into plant available forms, held in the soil, or even lost to air or water.

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AgroLife Scientific Journal - Volume 4, Number 1, 2015ISSN 2285-5718; ISSN CD-ROM 2285-5726; ISSN ONLINE 2286-0126; ISSN-L 2285-5718

Water relations - soil can regulate the drainage, flow and storage of water and solutes, which includes nitrogen, phosphorus, pesticides, and other nutrients and compounds dissolved in the water. With proper functioning, soil partitions water for groundwater recharge and for use by plants and soil animals. Biodiversity and habitat - soil supports the growth of a variety of plants, animals, and soil microorganisms, usually by providing a diverse physical, chemical, and biological habitat. Filtering and buffering - soil acts as a filter to protect the quality of water, air, and other resources. Toxic compounds or excess nutrients can be degraded or otherwise made unavailable to plants and animals. Physical stability and support - soil has the ability to maintain its porous structure to allow passage of air and water, withstand erosive forces, and provide a medium for plant roots. Soils also provide anchoring support for human structures and protect archeological treasures. This paper presents the main limiting factors of soil resources in Romania and and their influence on the physico-chemical soils characteristics. Soil degradation is a serious problem in Europe an also in Romania. It is caused or exacerbated by human activity such as inadequate agricultural and forestry practices, industrial activities, tourism, urban and industrial expansion etc. Damage to Europe’s soils from modern human activities is increasing and leads to irreversible losses due to soil erosion, local and diffuse contamination and the sealing of soil surfaces. Population growth coupled with urbanization is putting soils under pressure, while agricultural intensification is making soils more prone to erosion. Sealing of soil surfaces due to an increased urbanization and new infrastructures is the main cause of soil degradation in the most industrialized and populated countries of western and northern Europe. Sustainable management of soil as a natural resource, together with air and water, is one of the environmental challenges and priorities in the 5th Environmental Action Programme. Soil Quality Monitoring in Romania revealed a number of problems concerning land use in Romania following the manifestation of one or more limiting factors such as: moisture deficit,

salinization and alkalization, soil erosion, waterlogging, reduced organic matter content soil acidity, compaction, pollution, reduced edaphic volume etc. Soil degradation processes have a direct impact on water and air quality, biodiversity and climate change. The degradation of soil resources affect health and safety of agricultural and food products (Dumitru et al., 2000). The adoption of the EU Thematic Strategy for Soil Protection by the European Commission on 22 September 2006 has given formal recognition of the severity of the soil and land degradation processes within the European Union and its bordering countries. Soil degradation processes are driven or exacerbated by human activity. Climate change, together with individual extreme weather events, which are becoming more frequent, will also have negative effects on soil. Soil degradation processes occurring in the European Union include erosion, organic matter decline, compaction, salinization, landslides, contamination, sealing and biodiversity decline. RESULTS AND DISCUSSIONS From the perspective of crop production, soil fertility at its core is determined by soil life. Conventional agronomy as it is taught in most formal university settings does not prioritize soil life as the central force, and it could be argued that this is causal in the drastic decrease in agricultural soil fertility worldwide. Conventional fertility and management protocols are in many ways very destructive to soil life, and due to this have effected desertification, erosion, pollution of waterways, aquifers, and the environment in general. Romania's soil resources are shown in Figure 1. In recent years arable farmland harnessed in Romania is about 8 million ha. If in 10 years ago in Romania's arable land was used by 9.4 million ha, this has dropped significantly in recent years. The significant decrease in arable land used is added to a number of limiting factors that can influence the level of agricultural yield.

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The loss of macro porosity and pore continuity reduces strongly the ability of the soil to conduct water and air. • Reduced infiltration capacity results in

surface run-off, leading eventually to flooding, erosion and transport of nutrients and agrochemicals to open water.

• A poor aeration of the soil reduces plant growth and induces loss of soil nitrogen and production of greenhouse gases through denitrification in anaerobic sites.

Soil compaction occurs in most soils cultivated on an area around of 6.5 million hectares. Edaphic volume (Ve, fractions of unity). This is an index of the overall profile showing the fine material content without skeleton, useful to plants. It is expressed in percentages or fractions of units compared to 100 cm thick. For soils with thickness greater than 1 m, the values of the edaphic volume are higher than one. Edaphic volume reduced is recorded at skeletal soils with different percentages of skeleton on soil profile which is a limiting factor for the development of the root system of plants (Photo 8).

Photo 8. Low edaphic volume

For agricultural plots, the plots with large edaphic volume (35.5%) are predominant, followed by soils with very large (23.7%) and medium (20.3%) edaphic volume.

As regarding the soil types, the highest values are characteristic to Luvisols (1.11 fractions of unity), Phaeozems (1.10), Luvisols (1.07), Chernozems (0.92), while the lowest average values characterize Leptosols (0.19), Andosols (0.37), Rendzic Leptosols (0.37) and Entic Podzols (0.45). Soil organic carbon, the major component of soil organic matter, is extremely important in all soil processes. Organic material in the soil is essentially derived from residual plant and animal material, synthesised by microbes and decomposed under the influence of temperature, moisture and ambient soil conditions. The annual rate of loss of organic matter can vary greatly, depending on cultivation practices, the type of plant/crop cover, drainage status of the soil and weather conditions. There are two groups of factors that influence inherent organic matter content: natural factors (climate, soil parent material, land cover and/or vegetation and topography), and human-induced factors (land use, management and degradation). Organic matter exerts numerous positive effects on soil physical and chemical properties, as well as the soil’s capacity to provide regulatory ecosystem services (Brady et al., 1999). Particularly, the presence of organic matter is regarded as being critical for soil function and soil quality. The positive impacts of organic matter result from a number of complex, interactive edaphic factors; a non-exhaustive list of organic maters's effects on soil functioning includes improvements related to soil structure, aggregation, water retention, soil biodiversity, absorption and retention of pollutants, buffering capacity, and the cycling and storage of plant nutrients. Soil organic matter increases soil fertility by providing cation exchange sites and acting as reserve of plant nutrients, especially nitrogen, phosphorus, and sulfur, along with micronutrients, which are slowly released upon organic matter mineralization. As such, there is a significant correlation between soil organic matter content and soil fertility. The decrease in soil humus content recorded in most soils cultivated and low content in nitrogen, phosphorus and potassium of soils

108

with a direct influence on the yields obtained (Photo 9).

Photo 9. Low organic matter content

Soils containing organic matter have a better structure that improves water infiltration, and reduces the soil’s susceptibility to compaction, erosion, desertification and landslides. Soil contamination is the occurrence of pollutants in soil above a certain level causing a deterioration or loss of one or more soil functions. Also, soil contamination can be considered as the presence of man-made chemicals or other alteration in the natural soil environment. This type of contamination typically arises from the rupture of underground storage tanks, application of pesticides, percolation of contaminated surface water to subsurface strata, leaching of wastes from landfills or direct discharge of industrial wastes to the soil. The most common chemicals involved are petroleum hydrocarbons, solvents, pesticides, lead and other heavy metals. The occurrence of this phenomenon is correlated with the degree of industrialization and intensity of chemical usage.

CONCLUSIONS Soil resources from Romania in recent years an increase on the limiting factors for agricultural yield, which requires conservation measures of soils. Decreasing soil fertility with repercussions on the health and quality of agricultural yield should be a warning to limit soil degradation and rehabilitate them. Changing production technologies using high performance machines require extensive research to pursue their long-term effects on physical, chemical and biological properties of soils. A priority of the need to represent farmers' awareness about the decline of soil production potential. Government involvement in the adoption of measures for the recovery of soils in areas affected by one or more limiting factors. Develop a legislative framework to protect soil resources. Application good agricultural practices code by farmers for soil conservation. The total costs of soil degradation that could be assessed for erosion, organic matter decline, salinization, landslides and contamination on the basis of available data, would be up to 38€ billion annually for EU25. If we want a healthy life we need healthy soils which implies a change of soil resources exploitation. REFERENCES Brady N.C., Weil R.R., 1999. The nature and properties

of soils. Prentice Hall, Inc., Upper Saddle River, NJ. Florea N., 2003. Degradarea, protec ia i ameliorarea

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