Vol.:(0123456789) 1 3 Rendiconti Lincei. Scienze Fisiche e Naturali https://doi.org/10.1007/s12210-019-00833-5 Evaluation of soil quality index to assess the infuence of soil degradation and desertifcation process in sub‑arid terrestrial ecosystem Ali İmamoglu 1  · Orhan Dengiz 2 Received: 27 April 2019 / Accepted: 20 July 2019 © Accademia Nazionale dei Lincei 2019 Abstract Desertifcation is the process of land degradation resulting from the mutual interactions of physical, biological, political, social, economic and cultural factors with climatic changes. Desertifcation is considered to be the last stage of land degrada- tion. In recent years, various studies have been carried out to reveal efective natural and human factors on desertifcation. Important one of the parameters commonly used in these studies is the soil quality index. Soil quality refers to the soil’s capacity to function. Soil quality index cannot be measured directly; it is obtained by combining some physical, chemical and biological soil properties in a spatial sense. In this study, the relationship between some soil criteria and desertifcation has been discussed and evaluated. The research area covers the boundaries of the Kalecik district of Ankara and covers 116,000 ha. The study area consists of diferent geomorphological units and has semi-arid climate characteristics. In this study erosion risk, soil depth, texture, organic matter content, soil reaction, main material, drainage, salinization and alkalization, lime content and soil pollution of the soils of the research area were examined, and classifed by analytic hierarchy process method according to their degree of weight and assembled in geographic information systems environment in layer logic. As a result of analysis, soil quality map was obtained from the viewpoint of land degradation and desertifcation based on soil and land characteristics of the study area. According to the obtained result soil quality is determined: 39.2% of the study area as low, 54.5% as medium, and 6.2% as high. Keywords Land degradation and desertifcation · Soil quality assessment · Sub-arid fragile environment · Climate change 1 Introduction Desertifcation is the process of land degradation result- ing from the mutual interactions of physical, biological, political, social, economic and cultural factors with climatic changes. On desertifcation, resulting from adverse weather conditions such as human rough land usage and long-term droughts, there is no full scientifc consensus about who is responsible in the frst instance. Is it the human activity or climatic factors (Turkey Desertifcation Model 2017)? Desertifcation is considered to be the last stage of land degradation. Desertifcation is observed and often occurred in areas where has low total rainfall, inadequate water resources, long arid seasons, recurrent drought events, loose surface material and thin soil layer, a rare and at the same time covered with a sensitive vegetation environment (Türkeş 2012). Soil is the leading natural resource damaged by deser- tifcation. Soil loses some of its physical, chemical and biological properties due to desertifcation. It also loses its functionality as a result of the reduction and disappearance of some efciency parameters. All physical, chemical and biological degradation events are related to each other and these events lead to changes in soil hydrological characteris- tics, resistance to erosion, utility of nutrients, element cycle and carbon storage capacity (Lavado Contador et al. 2009; Agır et al. 2017). Over time, the loss of function of the soil and therefore the stopping of agricultural production is one of the inevitable consequences of desertifcation. In the same * Ali İmamoglu aliimamoglu@yandex.com 1 Geography Department, Faculty Art and Science, Nevşehir Hacıbektaş Veli University, Nevşehir, Turkey 2 Department of Soil Science Samsun, Agricultural Faculty, Ondokuz Mayis University, Samsun, Turkey