112 research outputs found
Impacts of Elephants Disturbances on Local Community: A Case Study of Sitalike Village Near Katavi National Park
Crop production is the principal economic activity in the local community surrounding Katavi National park. Elephant’s raids upon these crops are thought to be key constraints on income generation. This project made the first quantitative assessment of this problems .therefore this project addresses those impacts of Elephants disturbances to the local communities.Purposefully sampling were used in selecting a selected village Sitalike village and  random sampling method was used for selecting the sample households(respondents) .A total sample of 32 households were interviewed in this study. The structured questionnaire and discussions were used to get information relevant to the study. Descriptive statistics such as frequency and percentage were used to accomplish the objective and presentation of results of the study.Farmer perceptions on Elephants which induce disturbances and raids their crops were heavily influenced by farmer‘s ability to defend themselves. Common animals such as Rodents, Birds and cattle caused considerable crop damage but were not quantified in this study. Variations in crop damage were evident and are potentially related to distance of a village from the park boundaries, Elephants distribution and their movement patterns.This study documented the existence of Elephant’s disturbances in Sitalike village and has demonstrated that local community are willing and able to collaborate with any authority to address this problems .However multi year study is needed to allow a full assessment of the temporal and spatial patterns by this one year study. And assessment of the causal factors will allow the implementation of effective mitigation measures Key word: Disturbances, Conservatio
Gendered Access and Control Over Land and Water Resources in the Southern Agricultural Growth Corridor of Tanzania
This paper assessed the gendered access and control over land and water, using the Ihemi cluster of the Southern Agricultural Growth Corridor of Tanzania (SAGCOT) as a study area. Specifically, the paper answered the question on how decisions are made between men and women over land and water in the SAGCOT area, as well as how access and control over land and water is conducted. Data for this paper was drawn from the baseline study which was conducted for the project known as Laying Foundation for Effective Landscape-level Planning for Sustainable Development (LiFELand). A cross-sectional research design was used, whereby a questionnaire was administered to 167 women and 440 men. In addition, focus group discussions and key informant interviews were also conducted to complement and allow triangulation of data. Quantitative data was analyzed descriptively; while, qualitative data was analyzed using content analysis. In general, the results show that female headed households accounted for more than a quarter of the surveyed households; the number was slightly higher in the Njombe region. Results further show that women had no control over land and water as important productive resources in rural areas. The results also show that a larger proportion of both men and women had no right of occupancy over the land they owned hence their inability to use it as collateral in accessing loans from formal financial institutions. The paper therefore recommends efforts be made to empower women, hence enabling them to actively participate in decision-making, particularly regarding land and water. Equitable decision-making power can immensely enhance ecosystem conservation and sustainable utilization over land and water as women are the major actors in agriculture. To achieve gender equality there is a need for awareness creation for both men and women using gender sensitive programs that will allow not only equality in use but a sustainable utilization of Land and Water as important natural resources in the SAGCOT (Southern Agriculture Growth Corridor) areas
Water conservation can reduce future water-energy-food-environment trade-offs in a medium-sized African river basin
The need for achieving efficient and sustainable use of water resources is pressing, however, this often requires better understanding of the potential of water conservation, taking into account the impact on return flows, and the costs in relation to sectoral benefits. Using modelling and limited observational data we explore the costs and potential water savings of 24 combinations of water conservation measures in the Rufiji basin, Tanzania. We compare these costs with estimates of the value such water savings could generate from water use in three important economic sectors; agriculture, energy and downstream ecosystems with high tourism potential. The cost of water conservation measures (median: 0.07 USD m−3) is found to be: higher than the value of most uses of water for agriculture (growing crops in expanded irrigation sites) and the median value for hydropower generation (from a new mega dam currently under construction); and lower than the ecosystem value. Nevertheless, under our modelling assumptions, the volume of additional water required to supply planned irrigation expansion in the basin could be reduced by 1.5 BCM using water conservation methods that would be financially viable, given the value of competing uses of water. Water savings of this magnitude would reduce potential trade-offs between use of water for hydropower and ecosystem services, by allowing peak environmental flow releases even in dry years, and without reducing firm energy generation. This methodology is transferable and relevant for producing realistic assessments of the financial incentives for long-term sustainable water use in agriculture, given incentives for other uses. With most reservoirs now being built for multiple purposes improved understanding of trade-offs between different sectors and functions is needed
Use of a hydrological model for environmental management of the Usangu Wetlands, Tanzania
Wetlands / Rivers / Ecology / Environmental effects / Remote sensing / Hydrology / Simulation models / Water budget / Irrigated sites / Land cover / Time series analysis / Tanzania / Usangu Wetlands / Great Ruaha River
Assessing river basin development given water-energy-food-environment interdependencies
Many river basins in the Global South are undergoing rapid development with major implications for the interdependent water-energy-food-environmental (WEFE) ‘nexus’ sectors. A range of views on the extent to which such natural-human systems should be developed typically exist. The perceived best investments in river basins depend on how one frames the planning problem. Therefore, we propose an approach where the best possible (optimised) implementations of different river basin development scenarios are assessed by comparing their WEFE sector trade-offs. We apply the approach to Tanzania’s river basin, an area with multiple WEFE interdependencies and high development potential (irrigation and hydropower) and ecosystem services. Performance indicators are identified through stakeholder consultation and describe WEFE sector response under scenarios of river basin development. Results show considerable potential exists for energy and irrigation expansion. Designs that prioritise energy production adversely affect environmental performance, however, part of the negative impacts can be minimised through release rules designed to replicate the natural variability of flow. The reliability of monthly energy generation is more sensitive to environmental-oriented management than the cumulative annual energy production. Overall results highlight how sectoral trade-offs change depending on the extent of development, something that may be difficult to regulate in the future, and that there are important basin-scale interdependencies. Benefits and limitations of the approach and its application are discussed
Impact of invasive Lantana camara on maize and cassava growth in East Usambara, Tanzania
The impacts of invasive alien plant species on native plants are generally well documented, but little is known about the mechanisms underlying their impacts on crop growth. A better understanding of immediate as well as legacy effects and of direct and indirect impacts of invasive alien plant species is essential for an improved management of invaded cropland. We investigated how Lantana camara impacts the growth of two subsistence crops (maize and cassava) through competition for resources, allelopathy and the indirect plant–plant interactions. We carried out two pot experiments using soils from invaded abandoned, invaded cultivated and non-invaded cultivated crop fields. In the first experiment maize and cassava were grown alone or together with L. camara and half of the pots were treated with activated carbon to suppress allelochemicals. The effect of the soil microbial community on L. camara—crop interactions was assessed in a second experiment using autoclaved soil with 5% of soil from the three soil types. We found that L. camara reduced the growth of maize by 29%, but cassava was not affected. We did not find evidence of allelopathic effects of L. camara. Inoculation of autoclaved soil with microorganisms from all soil types increased biomass of cassava and reduced the growth of maize. Because L. camara only caused impacts when growing simultaneously with maize, the results suggest that removal of L. camara will immediately mitigate its negative impacts on maize
The role of superficial geology in controlling groundwater recharge in the weathered crystalline basement of semi-arid Tanzania
Study region: Little Kinyasungwe River Catchment, central semi-arid Tanzania. Study focus: The structure and hydraulic properties of superficial geology can play a crucial role in controlling groundwater recharge in drylands. However, the pathways by which groundwater recharge occurs and their sensitivity to environmental change remain poorly resolved. Geophysical surveys using Electrical Resistivity Tomography (ERT) were conducted in the study region and used to delineate shallow subsurface stratigraphy in conjunction with borehole logs. Based on these results, a series of local-scale conceptual hydrogeological models was produced and collated to generate a 3D conceptual model of groundwater recharge to the wellfield. New hydrological insights for the region: We propose that configurations of superficial geology control groundwater recharge in dryland settings as follows: 1) superficial sand deposits act as collectors and stores that slowly feed recharge into zones of active faulting; 2) these fault zones provide permeable pathways enabling greater recharge to occur; 3) ‘windows’ within layers of smectitic clay that underlie ephemeral streams may provide pathways for focused recharge via transmission losses; and 4) overbank flooding during high intensity precipitation events increases the probability of activating such permeable pathways. These conceptual models provide a physical basis to improve numerical models of groundwater recharge in drylands, and a conceptual framework to evaluate strategies (e.g., Managed Aquifer Recharge) to artificially enhance the availability of groundwater resources in these regions
Land cover changes in the Upper Great Ruaha (Tanzania) and the Upper Awash (Ethiopia) river basins and their potential implications for groundwater resources
Over the past century, the world has experienced an unprecedented surge in population growth, accompanied by a significant increase in economic activity and fuelled by an intensive utilization of natural resources, including water. This phenomenon has brought about profound alterations in land cover and land use patterns across various regions. Knowledge of land use changes is key to unlocking an understanding of water use changes and associated impacts on water resources, and potential threats to sustainability. However, the pace and nature of land use transitions vary widely across the globe, shaped by a complex interplay of local, regional and global factors, making systematic assessments important. This report presents the results of a land cover change analysis conducted in two river basins in sub-Saharan Africa: the Upper Great Ruaha River Basin (UGRRB) in Tanzania and the Upper Awash River Basin (UARB) in Ethiopia. The spatio-temporal analysis spans a recent 15-20-year period up until 2015/16 and utilizes remote sensing imagery, secondary maps and ground truth information for the two end point times (resolution: 30 m). The basins are significantly different in terms of agricultural development and water resource use. UARB represents an area with emerging commercial farms, urban expansion and diminishing natural vegetation, whereas UGRRB still retains significant natural vegetation but is experiencing an increase in smallholder agriculture as well as intensive commercial irrigation potentially affecting fragile wetland systems. In UGRRB, surface water is the main source of irrigation water, while in UARB, groundwater resources are increasingly used for irrigation by smallholder farmers. The findings reveal a common overall trend in both basins that is similar to many low-income countries, illustrating an expansion of agricultural and irrigated areas and human settlements at the expense of natural land cover. The report presents a detailed systematic remote sensing-based methodology to quantify and compare land cover transitions in time and space with high resolution, within and between agricultural landscapes of larger basins. The study highlights that land cover changes in the basins follow diverse and unique trajectories, providing critical insights into evolving land use patterns. In its conclusion, the study underscores the profound implications of recent land use changes for groundwater resources within these agro-pastoral systems. Overall, the report highlights the importance of sustainable land management and integrated water resources management, and provides valuable insights into the complexities of land use change in these regions
Land fragmentation, agricultural productivity and implications for agricultural investments in the Southern Agricultural Growth Corridor of Tanzania (SAGCOT) region, Tanzania.
There are polarized evidences of the impact of agricultural land fragmentation on land productivity. On the one hand there viewpoints which consider land fragmentation to harm agricultural productivity. On the other hand there are counter thoughts which view land fragmentation as a positive situation which allows farmers to cultivate many environmental zones, minimise production risk and optimise the schedule for cropping activities. We use the case of Ihemi cluster in the Southern Agricultural Growth Corridor of Tanzania (SAGCOT) to investigate the impact of land fragmentation on crop productivity. We furthermore discuss the nature and causes of land fragmentation in the SAGCOT region and its implication on the future structure of agricultural landholdings and welfare of smallholder farmers in the region. The results showed that the nature and level of fragmentation in the study area were the outcome of combined, rather than isolated influences of supply and demand driven factors. Overall, the
results did not support the claim that fragmentation reduces land productivity. This then implies that land fragmentation should not always be considered as defective. There were evidences of increasing chunks of land owned by rich farmers and investors which increased the possibility for increased consolidation of agricultural land under large scale farming. However, the landholdings for smallholder farmers might become increasingly more fragmented as poor smallholder farmers continue selling their land holdings to rich farmers and investors. Releasing the SAGCOT region’s potential for agricultural development will require that smallholder farmers are helped to secure adequate and suitable land for farming, raise agricultural productivity, diversify their sources of income, and adopt good production practices. This requires setting up a strong base of investor - farmer synergies for inclusive agricultural growth
The El Niño event of 2015-16: climate anomalies and their impact on groundwater resources in East and Southern Africa
The impact of climate variability on groundwater storage has received limited attention despite widespread dependence on groundwater as a resource for drinking water, agriculture and industry. Here, we assess the climate anomalies that occurred over Southern Africa (SA) and East Africa, south of the equator (EASE), during the major El Niño event of 2015-16, and their associated impacts on groundwater storage, across scales, through analysis of in situ groundwater piezometry and GRACE satellite data. At the continental scale, the El Niño of 2015-16 was associated with a pronounced dipole of opposing rainfall anomalies over EASE and Southern Africa, north/south of ~120S, a characteristic pattern of ENSO. Over Southern Africa the most intense drought event in the historical record occurred, based on an analysis of the cross-scale areal intensity of surface water balance anomalies (as represented by the Standardised Precipitation-Evapotranspiration Index, SPEI), with an estimated return period of at least 200 years and a best estimate of 260 years. Climate risks are changing and we estimate that anthropogenic warming only (ignoring changes to other climate variables e.g. 43 precipitation) has approximately doubled the risk of such an extreme SPEI drought event. These surface water balance deficits suppressed groundwater recharge, leading to a substantial groundwater storage decline indicated by both GRACE satellite and piezometric data in the 46 Limpopo basin. Conversely, over EASE during the 2015-16 El Niño event, anomalously wet conditions were observed with an estimated return period of ~10 years, likely moderated by the absence of a strongly positive Indian Ocean Zonal Mode phase. The strong but not extreme rainy season increased groundwater storage as shown by satellite GRACE data and rising groundwater levels observed at a site in central Tanzania. We note substantial uncertainties in separating groundwater from total water storage in GRACE data and show that consistency between GRACE and piezometric estimates of groundwater storage is apparent when spatial averaging scales are comparable. These results have implications for sustainable and climate-resilient groundwater resource management, including the potential for adaptive strategies, such as managed aquifer recharge during episodic recharge events
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