Predicting land use/cover changes and its association to agricultural production on the slopes of Mount Kilimanjaro, Tanzania

Abstract

Increasing demand for food production results in Land use and land cover (LULC) changes, which afflicts the provision of ecosystem services in high mountain areas. This work used time-series LULC and selected spatial metrics to predict the LULC changes for Kikafu-Weruweru-Karanga (KWK) watershed (on the southern slopes of Mt. Kilimanjaro) for the next decade. LULC maps were generated by classifying time-series satellite images. We further predicted the implications for selected staple crop production over the next decade. The simulated LULC shows expansion in built-up (by 32.55%/27.04 km 2 ) and agriculture (by 39.52%/52.0 km 2 ) areas from 2018 to 2030. These results suggest that urbanization is likely the next biggest threat to water availability and food production. Grasslands and wetlands are expected to decrease by 57.24% and 39.29%, respectively. The forest area is likely to shrink by 6.37%, about 9.82 km 2 , and 1.26 km 2 being converted to agriculture and built-up areas, respectively. However, expansion in agricultural land shows very little increase in staple food crop production records, suggesting that farm size plays a minor role in increasing crop production. Predicting the near future LULC around KWK is useful for evaluating the likelihood of achieving development and conservation targets that are set locally, nationally and internationally.

Evaluation and Prediction of the Impacts of Land Cover Changes on Hydrological Processes in Data Constrained Southern Slopes of Kilimanjaro, Tanzania

“…This study was done at the Kikafu, Weruweru, and Karanga (KWK) watershed, which spans from the thick mountain forest on the southern slopes of Mount Kilimanjaro (Figure 1a). The study area, rainfall pattern (Figure 1b), population and anthropic activities were detailed in Said, Komakech [28] and Said, Hyandye [41]. It is worth mentioning that the largest water extractor is agriculture, being dominated by small to large scale irrigation along the mountain slopes.…”

“…The assessment results are regarded as acceptable because Kappa values are greater than 80%, as Jensen ( 2007) stated. This procedure is detailed in Said, Hyandye [41]. These maps were independently used to simulate the hydrological impacts of land cover changes at the KWK watershed.…”

“…The expansion of agricultural land, built-up areas, and shrinking of grassland [41] may have resulted in increased surface runoff in the KWK watershed, especially in the lowlands. The changes in WatQ as a result of changes in vegetation is due to changes in CN values.…”

“…Some of the proposed strategies to curb the expansion of agriculture due to the demand for food to suffice the expanding population on the slopes of Mt. Kilimanjaro include the improvement of the land tenure security and the introduction of modern land and water conservation measures [41]. These strategies are aimed at increasing per capital production and discourage the opening up of more land for agriculture [34].…”

Effects of Land Use Change Related to Small-Scale Irrigation Schemes in Kilombero Wetland, Tanzania

“…Despite this conversion at large scales, production is generally fairly low, particularly in rainfed areas (Nakawuka et al, 2018). Similar observations have been reported from irrigation schemes in northern parts of Tanzania, where expansion of farming has reduced native species (Misana et al, 2012;Said et al, 2021). Brockington et al (2008) and Rowcroft (2005) reported that agricultural innovation and technologies have transformed much of the habitats beyond their recovery, and still there is a failure to meet production cost in an effective way.…”