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• Land cover dynamics in dry tropical environments are often overlooked. • Classification accuracy of 79–86% was attained using Landsat data. • Primary forest declined, while secondary forest increased. • Deforestation has continued to increase with low rates of recovery. • Forest connectivity declined by 22% between 1972 and 2016. Land cover dynamics in the tropical dry environments of sub-Saharan Africa are not well understood compared to humid environments, especially on a national scale. Previous studies describing land cover in the dry tropics are spatially or temporally constrained. This study presents the first long-term (1972–2016) nationwide land cover dynamics and forest connectivity analyses for Zambia. We employed 300 Landsat images and an object-based image analysis (OBIA) approach with the Random Forests (RF) classifier to map nine land covers at six time steps (1972, 1984, 1990, 2000, 2008 and 2016). Post-classification change detection was used to understand the dynamics, while landscape metrics were derived to assess the forest structural connectivity. Overall accuracies ranging from 79 to 86% were achieved. In 1972, 48% of Zambia was covered by primary forest and 16% was covered by secondary forest. By 2016, 62.74% of Zambia had undergone changes, with primary forest decreasing by 32% and secondary forest increasing by 23%. Our results showed that forests have been recovering by 0.03 to 1.3% yr−1 (53, 000–242, 000 ha yr-1); however, these rates are markedly lower than deforestation rates (- 0.54 to - 3.05% yr-1: 83, 000–453, 000 ha yr-1). Annual rates of change varied by land cover, with irrigated crops having the largest increase (+ 3.19 yr-1) and primary forest having the greatest decrease (-2.48% yr-1). Forest connectivity declined by 22%, with primary forest having the greatest decline, while the connectivity for secondary and plantation forest increased. We showed here that land cover in Zambia is highly dynamic with high rates of change, low forest recovery and decline in forest connectivity. These findings will aid in land use planning, reporting for the forthcoming 2020 Global Forest Resources Assessment, and carbon accounting, especially under the reduction in carbon emissions from deforestation and degradation programme (REDD+). [ABSTRACT FROM AUTHOR]

Abstract: Annual forest cover loss indicator maps for the humid tropics from 2000 to 2005 derived from time-series 500 m data from the MODerate Resolution Imaging Spectroradiometer (MODIS) were compared with annual deforestation data from the PRODES (Amazon Deforestation Monitoring Project) data set produced by the Brazilian National Institute for Space Research (INPE). The annual PRODES data were used to calibrate the MODIS annual change indicator data in estimating forest loss for Brazil. Results indicate that MODIS data may be useful in providing a first estimate of national forest cover change on an annual basis for Brazil. When directly compared with PRODES change at the MODIS grid scale for all years of the analysis, MODIS change indicator maps accounted for 75% of the PRODES change. This ratio was used to scale the MODIS change indicators to the PRODES area estimates. A sliding threshold of percent PRODES forest and 2000 to 2005 deforestation classes per MODIS grid cell was used to match the scaled MODIS to the official PRODES change estimates, and then to differentiate MODIS change within various sub-areas of the PRODES analysis. Results indicate significant change outside of the PRODES-defined intact forest class. Total scaled MODIS change area within the PRODES historical deforestation and forest area of study is 120% of the official PRODES estimate. Results emphasize the importance of synoptic monitoring of all forest change dynamics, including the cover dynamics of intact humid forest, regrowth, plantations, and cerrado tree cover assemblages. Results also indicate that operational MODIS-only forest cover loss algorithms may be useful in providing near-real time areal estimates of annual change within the Amazon Basin. [Copyright &y& Elsevier]

• The result of the study indicated that significant LULC changes have happened over the past 46 years. • The study revealed that forest land has declined from 20.9 % in 1973 to 13.7 % in 2019. • The study also revealed the decline of wetlands from 24.0 % in 1973 to 4.8 % in 2019. • LULC dynamics in the study area is driven by a combination of proximate and underlying causes. • The results of the study revealed that there is a significant increase in agricultural land, during the study periods Information on Land Use and Land Cover (LULC) changes and the driving forces behind such modifications underpin a proper understanding of the dynamics of LULC changes. This study aimed to analyse the dynamics of LULC change trends and its driving factors in Jimma Geneti District (JGD) for the year 1973–2019. Five satellite images downloaded from USGS were used to analyze and assess the geospatial and temporal changes in LULC. In addition, in-depth household interviews, key informant interview, focus group discussions (FGD) and field observations were used to address the drivers of LULC changes. The result showed a decline in forest land from 8632.5 ha (20.9 %) in 1973–5647.23 ha (13.7 %) in 2019. The study further revealed that the total of forest land cleared between 1973 and 2019 was estimated to be 2985.27 ha (7.22 %). In other words, 34.6 % of the forest cover that existed in 1973 was lost. Similarly, wetlands declined from 9919.5 ha (24.0 %) in 1973–2000.24 ha (4.8 %) in 2019. Similarly, wetlands declined from 9919.5 ha (24.0 %) in 1973–2000.24 ha (4.8 %) in 2019. On the other hand, cultivated land has increased from 18617.0 ha (45.1 %) to 27708.1 ha (67.1 %). Similarly, the increment in settlement areas has elevated from 908.7 ha (2.2 %) to 4436.46 ha (10.7 %) during the same period. Agricultural expansion, cutting trees for various purposes (such as firewood, charcoal and construction material), overgrazing and the expansion of settlements, were identified as the major proximate causes of these changes. Moreover, the major underlying drivers of LULC changes include population growth, changes in policy and institutions, poverty and lack of awareness on the importance of natural resource conservation for sustainable livelihoods. From this study, it can be concluded that JGD has experienced a significant change in LULC over the past 46 years and were affected both positively and negatively. Hence, a wide range of policy packages are required for sustainable land management practices which take in to account synergies and trade-offs between the various land uses in the study area. The national and local governments should enforce sustainable land management approaches through integrating land use planning and management into all development programmes and projects. [ABSTRACT FROM AUTHOR]