Donghang Zhang, Jiaxin Xiang, Yiyong Wei
Effects of flipped classroom teaching in anaesthesiology residents: a protocol for systematic review and meta-analysis
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article presents results soil water analysis plus plans maps report 1 issued 1974 saltaffected soils new irrigation district located semiarid bardenas area aragn northern spain fig 1 survey carried defunct institute agrarian reform development ie iryda spanish acronym work began january 1972 preliminary reconnaissance survey 53000 ha using aerial photographs scale 132000 usaf photogrammetric flight 195657 covered almost whole spain photographs flight available spanish aerial photograph viewer httpsfototecacnigesfototeca time levelling irrigation yet begun reconnaissance allowed selection area 32300 ha fig 1 relevant salinity symptoms like irrigated fields irregular crop growth detailed photo interpretation area carried 112000 scale flight august 1971 new irrigation district fed high quality water pyrenees soon faced salinity problems well known farmers echoed media 2 3 4 environment great social concern increasing agricultural production 5 report written spanish dated july 1974 soil profiles described sampled april 1972 march 1974 report 1 consists two volumes first memoria containing data surveys laboratory analyses pedological descriptions photographs soils land features agricultural importance well data calculations designing drainage selected plots second volume consists five folded plans location surveyed area scale 1200000 four plans scale 125000 b soilgeomorphologic units c soil units describing characteristics land use e locations described soil profiles field observations taken together data improved orthorectification gives picture salinity soil properties area reuse data comparisons evolution agriculture subsequent years especially soil salinity sodicity help evaluate agricultural practices last fifty years particularly intensive land levelling irrigation