Baseline Review of the Upper Tana, Kenya

http://greenwatercredits.net/sites/default/files/documents/isric_gwc_report8.pd

Combining interactive GIS tools and expert knowledge in validation of tree species models

Poster presented at XIII Congreso Forestal Mundial. FAO, Buenos Aires (Argentina). 18-25 Oct 200

Water and energy footprint of irrigated agriculture in the Mediterranean region

Irrigated agriculture constitutes the largest consumer of freshwater in the Mediterranean region and provides a major source of income and employment for rural livelihoods. However, increasing droughts and water scarcity have highlighted concerns regarding the environmental sustainability of agriculture in the region. An integrated assessment combining a gridded water balance model with a geodatabase and GIS has been developed and used to assess the water demand and energy footprint of irrigated production in the region. Modelled outputs were linked with crop yield and water resources data to estimate water (m3 kg−1) and energy (CO2 kg−1) productivity and identify vulnerable areas or 'hotspots'. For a selected key crops in the region, irrigation accounts for 61 km3 yr−1 of water abstraction and 1.78 Gt CO2 emissions yr−1, with most emissions from sunflower (73 kg CO2/t) and cotton (60 kg CO2/t) production. Wheat is a major strategic crop in the region and was estimated to have a water productivity of 1000 t Mm−3 and emissions of 31 kg CO2/t. Irrigation modernization would save around 8 km3 of water but would correspondingly increase CO2 emissions by around +135%. Shifting from rain-fed to irrigated production would increase irrigation demand to 166 km3 yr−1 (+137%) whilst CO2 emissions would rise by +270%. The study has major policy implications for understanding the water–energy–food nexus in the region and the trade-offs between strategies to save water, reduce CO2 emissions and/or intensify food production

Maintaining ecological soil functions - techniques in organic farming systems

The ecological soil functions (e.g. habitat and living space, production and utilization, ecological regulation) have to be taken into account and maintained by farming systems. Organic farming systems can provide for this by using suitable crop rotations, manure management methods and tillage techniques

Global Soil Organic Carbon Estimates and the Harmonized World Soil Database

Global estimates of soil organic carbon stocks have been produced in the past to support the calculation of potential emissions of CO2 from the soil under scenarios of change land use/cover and climatic conditions (IPCC, 2006), but very few global estimates are presented as spatial data. For global spatial layers on soil parameters, the most recent and complete dataset is available as the Harmonized World Soil Database (HWSD) (Fisher et al., 2008).The HWSD represents a step forward towards a spatially more detailed and thematically more refined set of global soil data. During the evaluation of the data for generating estimates of global SOC stocks Version 1.1 of the HWSD revealed also some rough edges. Consequential are the values of bulk density attributed to soils high in organic carbon. In the evaluation the database was completed and suitable substitutions for bulk density for soil high in organic carbon were investigated. For the amended data the global SOC stock to 100cm soil depth is estimated at 1, 417 Pg C, although this estimate very much dependent on the ancillary data used. The amended HWSD was compared to data from 4 other global data sets on SOC stocks. The comparative evaluation has demonstrated that bulk density is the most important factor for estimating SOC stocks and mainly responsible for the differences between estimates. Moist affected from the variability in bulk density are SOC stocks in areas with soils which are high in organic carbon.JRC.H.5-Land Resources Managemen