Semi-steppe rangelands are a complex, highly dynamic and often multi-layered mosaic of grassland, shrubland, and intermediate communities. A few recent studies have explicitly or implicitly developed synthetic hypotheses about how interactive effects of human made disturbances initiate dynamic changes in plant community composition to cause a shifting mosaic of vegetation pattern across the lan...

Cone photoreceptors in the zebrafish retina are arranged in a crystalline lattice, with each spectral subtype at a specific position in the array; rod photoreceptors are inserted around the cones. Patterning events and developmental mechanisms that lead to the formation of the cone mosaic are not known. To begin investigating this issue, we examined the initial stages of opsin expression in zeb...

Forest communities are mosaic systems composed of patches classified into four different developmental patch types: gap patch (G), building patch (B), mature patch (M) and degenerate patch (D). To study the mechanisms maintaining diversity in subalpine coniferous forests, species presence frequency and diversity in the four distinct patch types (G, B, M and D) of Larix chinensis conifer forests...

This paper applies concepts of landscape ecology and patch dynamics to lotic systems. We present a framework for the investigation of pattern and process in lotic ecosystems that considers how specific patch characteristics determine biotic and abiotic processes over various scales. Patch characteristics include: size, size distribution within the landscape, juxtaposition, diversity, duration, ...

Quantifying the spatial integrity and patterns of dry/wet events over land is essential to understand how local hydrological regime responds environmental changes. Spatial aggregation changes in dry wet areas have not been studied extensively. Based on a patch-mosaic landscape model, we analyzed at two levels corresponding design during 1949 2018. At level, global degree increased initially the...

The spatial genetic composition of hybrid zones exhibits a range of possible patterns, with many characterized by patchy distributions. While several hypothetical explanations exist for the maintenance of these "mosaic" hybrid zones, they remain virtually unexplored theoretically. Using computer simulations we investigate the roles of dispersal and assortative mating in the formation and persis...

A landscape may be viewed as a mosaic of patches. The state of the ecosystem can be defined by the abundance of species measured in some appropriate way. Within each patch the species populations change as the result of mortality and establishment. Through time, species populations are disappearing in some patches and dispersing to and becoming established in others where they are absent; the g...

This paper presents a novel practical solution for registering a set of partially overlapping range images of an arbitrary scene. It was developed for application in remote telerobotic operation in unstructured environments. The method is based on simple matching of 2-D range profiles extracted from two images. It handles all six degrees of freedom and does not rely on any particular geometric ...

semi-steppe rangelands are a complex, highly dynamic and often multi-layered mosaic of grassland, shrubland, and intermediate communities. a few recent studies have explicitly or implicitly developed synthetic hypotheses about how interactive effects of human made disturbances initiate dynamic changes in plant community composition to cause a shifting mosaic of vegetation pattern across the lan...