Inequitable Gains and Losses from Conservation in a Global Biodiversity Hotspot

A billion rural people live near tropical forests. Urban populations need them for water, energy and timber. Global society benefits from climate regulation and knowledge embodied in tropical biodiversity. Ecosystem service valuations can incentivise conservation, but determining costs and benefits across multiple stakeholders and interacting services is complex and rarely attempted. We report on a 10-year study, unprecedented in detail and scope, to determine the monetary value implications of conserving forests and woodlands in Tanzania’s Eastern Arc Mountains. Across plausible ranges of carbon price, agricultural yield and discount rate, conservation delivers net global benefits (+US$8.2B present value, 20-year central estimate). Crucially, however, net outcomes diverge widely across stakeholder groups. International stakeholders gain most from conservation (+US$10.1B), while local-rural communities bear substantial net costs (-US$1.9B), with greater inequities for more biologically important forests. Other Tanzanian stakeholders experience conflicting incentives: tourism, drinking water and climate regulation encourage conservation (+US$72M); logging, fuelwood and management costs encourage depletion (-US$148M). Substantial global investment in disaggregating and mitigating local costs (e.g., through boosting smallholder yields) is essential to equitably balance conservation and development objectives

Environmental impact of cereal-tobacco farming system in Miombo Woodlands: A case study of Uyui District, Tabora Region, Tanzania

A study was conducted in the cerealtobacco farming system in Uyui District, Tabora region. The results revealed that depletion of closed woodland between 1970 and 1980 was 380 hectares per year and between 1980 and 1997 was 40 hectares per year. The results also showed that cultivated land increased by 225 and 240 hectares annually between 1970 - 1980 and between 1980 – 1997, respectively. The expansion of the cultivated land was at the expense of the Miombo woodlands. Key socio-economic factors identified by the study as drivers for the observed degradation of Miombo woodland include population growth, agricultural expansion and increased demand for fuelwood for tobacco curing. Keywords: Cereal-tobacco farming, Miombo woodland, Shifting cultivation, Deforestation, Tabor

A GIS Tool to Estimate Flow at Ungaged Basins Using the Map Correlation Method

Water resources management has been a critical component of sustainable resources planning. One of the most commonly used data in water resources management is streamflow measurements. Daily streamflow time series collected at a stream gage provide information on the temporal variation in water quantity where the gage is located. However, streamflow information is often needed at ungaged catchments especially when the stream gage network is not dense. One conventional approach to estimate streamflow at an ungaged catchment is to transfer streamflow measurements from the spatially closest stream gage, commonly referred to as the donor or reference gage using the drainage-area ratio method. Recently, the correlation between daily streamflow time series is proposed as an alternative to distance for reference stream gage selection. The Map Correlation Method (MCM) enables development of a map that demonstrates the spatial distribution of correlation coefficients between daily streamflow time series at a selected stream gage and all other locations within a selected study area. Although utility of the map correlation method has been demonstrated in various studies, due to its geostatistical analysis procedure it is time-consuming and hard to implement for practical purposes such as installed capacity selection of run-of-river hydropower plants during their feasibility studies. In this study, an easy-to-use GIS-based tool, called MCM_GIS is developed to apply the MCM in estimating daily time series of streamflow. MCM_GIS provides a user-friendly working environment and flexibility in choosing between two types of interpolation models, kriging and inverse distance weighting. The main motivation of this study is to increase practical application of the MCM by integrating it to the GIS environment. MCM_GIS can also carry out the leave-one-out cross-validation scheme to monitor the overall performance of the estimation. The tool is demonstrated on a case study carried out in Western Black Sea Region, Turkey. ESRI's ArcGIS for Desktop product along with a Python script is utilized. The outcomes of inverse distance weighting and ordinary kriging are compared. Results of GIS-based MCM are in good agreement with the observed hydrographs