Soil Advances 

Abstract: Understanding the impact of changes in land use/land cover (LULC) on carbon sequestration (Cseq) and emission leads to achieving sustainable development goals (SDGs). For this, Business-As-Usual (BAU) and Sustainable Development (SD) scenarios were examined in Azarshar city, Iran which is faced with urban intensification. The spatiotemporal dynamics of the carbon cycle and influences of various urban growth indicators are still unclear even under climate change, rapid urbanization, and ecological deterioration. In this research, total carbon storage (Cts) and Cseq were determined at four carbon pools i.e., aboveground carbon (AGC), belowground carbon (BGC), dead organic carbon (DeOC), and soil organic carbon (SOC). This research revealed a successful implementation of integrated CA-Markov and InVEST models in delineating LULC changes between 2013 and 2033. It was concluded that land resources management play a crucial role in decreasing Cseq along with increasing carbon emission across the study area. The modelling results showed a significant shifting from barren and cropland to developed land uses. This research goes beyond providing supporting evidence that urban expansion is a key factor driving the aforementioned changes, but also illustrates the importance of remote sensing in ecological modelling, especially where information is sparse.

Abstract: The study examines the directionality of mineralization–synthesis processes of soil organic matter under contrasting crop fertilization regimes. Given the close interdependence of the carbon and nitrogen cycles, the dynamics of N 2 O and CO 2 emissions were assessed in a long-term field experiment on leached chernozem soil within a short-rotation system of potatoes, spring barley, peas, and winter wheat. Application of 40 t/ha of farmyard manure markedly distinctly mineralization during the first year, followed by a gradual decline in subsequent years. Continuous use of mineral fertilizers alone intensified mineralization, with further increases at higher nitrogen rates. In contrast, low mineral fertilizer rates (≤ N 40 P 40 K 40 ), combined with the direct and residual effects of straw and lupine green manure, promoted synthetic processes. Medium doses (N 60 P 60 K 60 – N 80 P 80 K 80 ) applied on an organic background resulted in a balanced dynamic between mineralization and synthesis. At high doses (N 90 P 90 K 90 – N 120 P 120 K 120 ), the addition of straw and green manure reduced N–N 2 O and C–CO 2 losses compared with mineral-only treatments; nevertheless, mineralization remained the prevailing process. • Directionality of mineralization–synthesis of OM in soil was assessed using the N–N 2 O:C–CO 2 emission ratio. • Incorporation of winter wheat straw and lupine green manure enhanced synthetic processes in leached chernozem. • Use of mineral fertilizer intensified mineralization in proportion to application rates. • Combining mineral fertilizers with straw and green manure improved the mineralization–synthesis balance of OM in soil. • Evaluating biological process directionality enables rapid identification of effective integrated fertilization strategies.