Search results for "Watershed"
showing 2 items of 62 documents
What makes segmentation good? A case study in boreal forest habitat mapping
2013
Segmentation goodness evaluation is a set of approaches meant for deciding which segmentation is good. In this study, we tested different supervised segmentation evaluation measures and visual interpretation in the case of boreal forest habitat mapping in Southern Finland. The data used were WorldView-2 satellite imagery, a lidar digital elevation model (DEM), and a canopy height model (CHM) in 2 m resolution. The segmentation methods tested were the fractal net evolution approach (FNEA) and IDRISI watershed segmentation. Overall, 252 different segmentation methods, layers, and parameter combinations were tested. We also used eight different habitat delineations as reference polygons agains…
Transformations Accompanying a Shift from Surface to Drip Irrigation in the Cànyoles Watershed, Valencia, Spain
2017
Drip irrigation is widely promoted in Spain to increase agricultural production and to save water. In the Cànyoles watershed, Valencia, we analysed the consequences of change from surface irrigation to drip irrigation over the past 25 years. There were a number of transformations resulting from, or accelerated by, this change including the 1) intensification of well construction causing a redistribution in access to groundwater, water shortages and a lowering of the groundwater table; 2) expansion of irrigation into former rain-dependent uphill areas resulting in increased water use; 3) shift to higher- value monoculture fruit crops, but with associated higher crop water requirements; 4) in…