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MEMO 89.2 <br /> <br /> _~ <br />- <br /> ~~ <br />' - <br />_ ~~; <br />~ <br /> }~ <br />R , <br />~ {` ' <br />~ ~ <br />I <br />! <br /> ~ ; <br />~` : ~~ * <br /> <br />r 9, y <br />, X01 <br />-. 4 <br />'.~~ <br />ti. <br /> <br />~,.. 4 <br />A <br /> <br />~. <br /> <br />Y, <br />` <br />~. ,' {. <br /> <br /> _ _ _ <br />Figure 7. Delineation of FSA Reference Parcels Using Buffer Zones <br />2.5 Classification <br />The classification procedure conducted was hierarchical, starting with the discrimination of irrigated <br />lands from non-irrigated lands through interpretation and analysis of multi-temporal NDVI data derived <br />from Landsat imagery. This preliminary irrigated lands classification was combined with DOQQs to <br />delineate irrigated parcel boundaries as described in the SPDSS Memorandum for Task 90.2. Once the <br />parcels were delineated, irrigated lands were classified into major crop types using the ERDAS Imagine <br />Maximum Likelihood Classifier (MLC). The maximum likelihood classifier is one of the most popular <br />methods of classification in remote sensing, in which a pixel with the maximum likelihood is classified <br />into the corresponding class (e.g. Jensen, 1996). <br />Reference data collected from FSA, as described in Section 2.4, were used to train the MLC and evaluate <br />classification performance. The MLC classification was combined with GIS and other ancillary data in a <br />series of rules to assign crop type information to the previously delineated agricultural parcels. In <br />addition, inputs of water commissioners, water users, ditch companies, and field observations were used <br />to refine the classification in an iterative process. <br />2.5.1 Classification of Irrigated Lands <br />The classification of irrigated lands consisted of two main processes including, (1) multitemporal analysis <br />and, (2) classification refinement. In the first process, reference data obtained from FSA and other <br />sources was used to analyze temporal signatures of irrigated and non-irrigated cover types (Figure 8). <br />Page 12 of 45 ~Rlversfde FecAnotogy, fnc. <br />4'JaYer Resources Errgi~ecr:np an~i CansuFlrnp <br />