Spatial-temporal evolution, mechanism and vegetation restoration of abandoned farmland in the Maolan national nature reserve

To elucidate the spatial-temporal change of abandoned land and its driving mechanism is one of the most important fields in recent research of land use/change. The Maolan karst natural reserve is well preserved as a typical karst forest ecosystem and world natural heritage. This paper aims to clarify the spatial-temporal evolution of abandoned land in this area based on the high-resolution remote sensing images and field investigations, using the Arcmap and Fragstats software. The results show that in the study area, the whole area of abandoned land mainly concentrates in the buffer zone and experimental area, namely Dongjia, Biba-lapa and Banlao-dongjiu in the northwest, south and northeast of the study area. From 2005 to 2015, the spatial distribution of the abandoned land area decreased significantly, while plaque area gradually increased. Between 2005 and 2010, the number of abandoned land and distance from settlements were positively correlated. In 2015, abandoned land was mainly distributed in settlement < 200 m, 600-800 m and > 1,000 m of the buffer area, respectively. The vegetation restoration of abandoned land was mainly distributed in the core and buffer area, but there was repeated cultivation after land abandonment in the experimental area with many rural settlements and artificial disturbs. The reason of farmland abandonment in the Maolan karst natural reserve was related firstly with the decrease of rural settlement and people. Secondly, it was related with the intensive use of cultivated land in the experimental area and buffer zone, and thirdly, with the farm household livelihood diversity and transition. These results could provide complete reference for understanding the human-natural relationship evolution and ecological restoration in the Maolan karst natural reserve area.