Geomorphometric analysis for characterizing landforms in Morelos State, Mexico

Landforms can be described and quantified into simple relief elements by parametrization of digital elevation model (DEM). In this research, we investigate the use of morphometric parameters and a new classification scheme to characterize selected elemental forms associated with landforms. We apply and test this methodology on a geomorphologically diverse region located in Central Mexico. These simple elements are known as morphometric classes and include ridge, plane, channel, pit, peak, and pass. These classes correspond to real entities and are of practical significance. The morphometric classes were grouped according to their areal parameters (ridge, plane, and channel) and pointed parameters (pit, peak, and pass), which can be used to form the basis of a system of characterization and classification of landforms. Landform elements display statistically significant compositional differences with respect to their proportions of morphometric classes. This, in turn, can be plotted onto a diagram of characterization and classification known as a double ternary diagram (DTD), which comprises both areal and pointed parameters and any combination thereof. The DTD is useful for studying geomorphological processes wherein areal and point values and properties have expressions which are topographically quantifiable. (c) 2004 Elsevier B.V. All rights reserved

Role of Digestive Gland in the Energetic Metabolism of Penaeus setiferus

Volume: 189Start Page: 168End Page: 17

Delineation of valleys and valley floors

Methods to automatically derive landforms have typically focused on pixel-based, bottom-up approaches and most commonly on the derivation of topographic eminences. In this paper we describe an object-based, top-down algorithm to identify valley floors. The algorithm is based on a region growing approach, seeded by thalwegs with pixels added to the region according to a threshold gradient value. Since such landforms are fiat we compare the results of our algorithm for a particular valley with a number of textual sources describing that valley. In a further comparison, we computed a pixel-based six-fold morphometric classification for regions we classified as either being, or not being, valley floor. The regions classified as valley floor are dominated by pla nar slopes and channels, though the algorithm is robust enough to allow local convexities to be classified as within the valley floor. Future work will explore the delineation of valley sides, and thus complete valleys