Small wetlands in Kenya and Tanzania cover about 12 million ha and are increasingly converted for agricultural production. There is a need to provide guidelines for their future protection or use, requiring their systematic classification and characterisation. Fifty-one wetlands were inventoried in 2008 in four contrasting sites, covering a surveyed total area of 484 km 2 . Each wetland was subdivided into sub-units of 0.5-458 ha based on the predominant land use. The biophysical and socio-economic attributes of the resulting 157 wetland sub-units were determined. The wetland sub-units were categorized using multivariate analyses into five major cluster groups. The main wetland categories comprised: (1) narrow permanently flooded inland valleys that are largely unused; (2) wide permanently flooded inland valleys and highlands floodplains under extensive use; (3) large inland valleys and lowland floodplains with seasonal flooding under medium use intensity; (4) completely drained wide inland valleys and highlands floodplains under intensive food crop production; and (5) narrow drained inland valleys under permanent horticultural production. The wetland types were associated with specific vegetation forms and soil attributes.Electronic supplementary material The online version of this article (

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Deforestation and forest degradation has been observed to be rampant in Masito-Ugalla ecosystem, Kigoma Region, western part of Tanzania. This paper therefore, intended to assess the extent of deforestation and forest degradation in the area, and to determine their causes. A total of 101 respondents were considered as the sample size for this study. The methods used for data collection were household questionnaire interviews, in-depth interviews, focus group discussions, analysis of satellite images and direct observation. The findings indicated that deforestation was occurring in the study area. Satellite data revealed diminished closed woodland, bushed grassland, forest and thickets between 1990 and 2014. On the contrary, settlement area, cultivated land and open woodland had increased during the same time frame. Proximate factors causing deforestation and forest degradation included agricultural expansion, wood extraction and expansion of settlement area. Underlying factors included population growth, poverty, poor levels of education, lack of employment, corruption and embezzlement of public funds by politicians and senior government officials; and high demand for fuel-wood. Biophysical drivers like incidences of unplanned wildfires and socio trigger events notably civil strife were also important. In order to minimize the problem and based on the factors augmenting deforestation and forest degradation in the MasitoUgalla ecosystem and their coupled negative consequences, effective environmental conservation education, increased patrols, effective law enforcement and provision of alternative energy sources are necessary.

This paper presents the findings of a study that analyzed land use and cover change, their driving forces and the socioeconomic implications on the southern and eastern slopes of Mount Kilimanjaro. This study is based on data extracted from remote sensing techniques using 1973, 1984 and 1999/2000 satellite images and household interviews. The major change detected in the study area from satellite images was expansion of cultivation at the expense of natural vegetation. The area under cultivation increased from 54% in 1973 to 62 and 63% in 1984 and 2000, respectively. Expansion and intensification of cultivation were noted particularly in the lowlands while some forest areas in the highlands had become degraded. These changes led to changes in cropping patterns and crop diversification, declined productivity of land and food insecurity. The underlying drivers of these changes were demographic, government policies, economic factors, socio-cultural factors including the land tenure system, institutional factors, technological change and infrastructure development. Investments in irrigation technology, introduction of new crop varieties and government interventions to support the poor are required to improve the productivity of land and reduce the vulnerability of the people to environmental perturbations, including drought.

The paper describes the assessment of the vegetation and the land use systems of the Malinda Wetland in the Usambara Mountains in Tanzania with the parachute UAS (unmanned aerial system) SUSI 62. The area of investigation was around 8 km². In two campaigns, one in the wet season and one in the dry season, approximately 2600 aerial photos of the wetland were taken using the parachute UAS SUSI 62; of these images, ortho-photos with a spatial resolution of 20 cm x 20 cm, were computed with an advanced block bundle approach. The block bundles were geo-referenced using control points taken with differential GPS. As well a digital surface model (DSM) of the wetland was created out of the UAS photos. Using the ortho-photos it is possible to assess the different land use systems; the differences in the phenology of the vegetation between wet and dry season can be investigated. In addition, the regionalisation of bio mass samples on smaller test plots was possible. The ortho-photos and the DSM derived from the UAS proved to be a valuable ground truth for the interpretation of Terra-SAR X images. The campaigns demonstrated that SUSI 62 was a suitable, robust tool to obtain the valuable information under harsh conditions.