Impact of Land Use and Land Cover Changes on Surface Runoff and Sediment Yield in the Little Ruaha River Catchment

Little Ruaha River catchment (6370 Km2) in the Southern Agricultural Growth Corridor of Tanzania (SAGCOT), is one of the country’s most significant waterways due to its ecological composition and economic value. Regardless of its ecological and economical value, the regional hydrologic condition has been tremendously affected due to land uses alteration, influenced by different socio-economic factors. This study aimed to understand the associated impacts of the present Land Use Land Cover (LULC) change on the surface runoff and sediment yield in the Little Ruaha River Catchment. Hydrological modelling using Soil and Water Assessment Tool (SWAT Model) was done to quantify the impact of land use and land cover dynamics on catchment water balance and sediment loads. The calibration and validation of the SWAT model were performed using sequential uncertainty fitting (SUFI-2). The results showed that, for the given LULC change, the average annual surface runoff increased by 2.78 mm while average annual total sediment loading increased by 3.56 t/ha, the average annual base flow decreased by 2.68 mm, ground water shallow aquifer recharge decreased from 2.97 mm and a slight decrease in average annual ground water deep aquifer recharge by 0.14 mm. The model predicts that in the future, there will be a further increase in both surface runoff and sediment load. Such changes, increased runoff generation and sediment yield with decreased base flow have implications on the sustenance flow regimes particularly the observed reduced dry season river flow of the Little Ruaha River, which in turn cause adverse impacts to the biotic component of the ecosystem, reduced water storage and energy production at Mtera Hydroelectrical dam also increasing the chances of flooding at some times of the year. The study recommends land use planning at the village level, and conservation agricultural practices to ameliorate the current situation. Developing multidisciplinary approaches for integrated catchment management is the key to the sustainability of Little Ruaha River catchment.

Illegal Wildlife Trade: Trade Flows of Wildlife Products and Facilitation Methods in the Ruaha Landscape, Tanzania

Tanzania’s Ruaha landscape is prominent for its potential wildlife resources, which play a key role in sustaining the economy and livelihoods of the people. However, most of these resources are illegally obtained and traded in different places within and outside the Ruaha landscape. Due to its illegal nature, most of the important information regarding the trade is poorly documented. Therefore, the current study aimed first, to explore the origin and destination of wildlife products;second, to assess the relationship between hunters and buyers or customers;third, to assess the means used to transport wildlife products;and lastly, to assess who influences people to engage in illegal hunting and trade activities. In addition, we assess the materials used in the exchange of wildlife products. Semi-structured questionnaires and face-to-face interviews were used to collect information from 123 respondents. Social network analysis was used to indicate the origin and destination of wildlife products. The findings show that 70% of wildlife products originate from the Ruaha National Park and MBOMIPA wildlife management areas, with the remaining 30% originating from villages. The majority of respondents (65%) reported transporting wildlife products by foot and bicycle as the primary modes of transportation. Suppliers of wildlife products are reported to have close and long-term relationships with their customers and traders, with most of whom being friends and relatives. We found most poachers to be influenced by their friends and relatives in terms making decision to engage in illegal wildlife trade. In addition, crops like maize and rice were the most popular products used to exchange with wildlife products in the Ruaha landscape. Therefore, in order to combat illegal trade in wildlife products at the local level, alternative income-generating activities need to be promoted accompanied by not only well-funded anti-poaching programmes but also more effective surveillance plans. These should entail the use of advanced techniques and skills, such as wildlife forensics.

Characterization of Some Typical Soils of the Miombo Woodland Ecosystem of Kitonga Forest Reserve, Iringa, Tanzania： Physico-Chemical Properties and Classification

Despite the fact that miombo woodland soils have significant implications in global climate change processes, few studies have been done to characterize and classify the soils of the miombo woodland ecosystem of Tanzania. The current study was carried out to map and classify soils of Kitonga Forest Reserve, which is a typical miombo woodland ecosystem, in order to generate relevant information for their use and management. A representative study area of 52 km2 was selected and mapped at a scale of 1：50,000 on the basis of relief. Ten representative soil profiles were excavated and described using standard methods. Soil samples were taken from genetic soil horizons and analyzed in the laboratory for physico-chemical characteristics using standard methods. Using field and laboratory analytical data, the soils were classified according to the FAO-World Reference Base （FAO-WRB） for Soil Resources system as Cambisols, Leptosols and Fluvisols. In the USDA-NRCS Soil Taxonomy system the soils were classified as Inceptisols and Entisols. Topographical features played an important role in soil formation. The different soil types differed in physico-chemical properties, hence exhibit differences in their potentials, constraints and need specific management strategies. Texture varied from sandy to different loams; pH from 5.1 to 5.9; organic carbon from 0.9 g/kg to 20 g/kg; and CEC from 3 cmol/（＋）kg to 24 cmol/（＋）kg. Sustainable management of miombo woodlands ecosystem soils requires reduced deforestation and reduced land degradation.