Monitoring the Land Degradation Neutrality in Saline and Sodic Lands after Reclamation and Agricultural Activities

• Main Authors: Mesut BUDAK, Hikmet GÜNAL, Orhan Mete KILIÇ, Nurullah ACİR
• Format: Article
• Language: English
• Published: Siirt University 2020-06-01
• Series: Türkiye Tarımsal Araştırmalar Dergisi
• Subjects: salinity; sodicity; landsat; normalized difference vegetation index (ndvi); land degradation neutrality
• Online Access: https://dergipark.org.tr/tr/pub/tutad/issue/54650/720139

Prevention of agricultural land degradation due to the natural or anthropogenic impacts and recovery of degraded lands have recently become among the strategic targets of many countries. In this context, the concept of land degradation neutrality (LDN) is defined as an indicator of reducing the rate of land degradation and increasing the rate of improvement in degraded lands. Land degradation neutrality in a region or in the terrestrial ecosystem can be achieved if productive land area and thus sustainable land use remains constant or increases. In this study, the effects of reclamation activities and agricultural production initiated in the pasture, which was naturally occurred with saline/sodic properties, were evaluated within the framework of LDN. In the assessment of LDN, net primary productivity (NPP) of pasture under post-reclamation agricultural activities, the normalized difference vegetation index (NDVI) for pre-reclamation and post-reclamation periods, and soil organic carbon stock (TOCS) data were used. Irrigation water was not sufficient for the whole area; therefore, reclamation was carried out in an area of approximately 1200 ha. In this context, disturbed and undisturbed soil samples were taken from 202 points of the study area in 2008 and 2012. Organic matter (OM), bulk density, soil reaction (pH) and electrical conductivity (EC) of soil samples were determined and evaluated. The mean TOCS content of the study area in the pre-reclamation period was 40.51 tons ha-1, while it was increased to 44.68 tons ha-1 after the reclamation and agricultural activities. The NDVI and NPP values, which were between -0.044 and + 0.060 and 125 and 250 g C m-2 in pre-reclamation period, increased to 0.419 - 0.631 and 0.234 - 0.551; and 200 - 475 g C m-2 and 200 - 407 g C m-2 after the reclamation and agricultural activities in 2013 and 2017, respectively. The mean OM content of the study area in the pre-reclamation period was 2.09% and the OM content increased to 2.16% in the pre-reclamation period. The EC values decreased from 4.08 dS m-1 to 2.26 dS m-1. The findings of the study indicated that land management practices adopted in the land reclamation had a positive impact on land productivity as well as to the LDN. In addition, this study reveals the importance of updated databases for monitoring land degradation and neutrality.