in many studies, topographic factors have been considered as an important factor in establishing the vegetation in different ecosystems. so, it affects vegetation composition and diversity by influencing soil moisture, fertility and soil depth. the aim of this research was to investigate the effects of slope, elevation and geographical aspects on species growth, forage production and vegetation...

species diversity is one of the important characteristics shows rangeland ecosystems changes, which isalready under effects of management practices. thus, this research was conducted to study speciesdiversity variation and assess suitable distributive abundance model in three rangeland sites in westazerbaijan. these sites were almost similar in environmental properties and differ in view point ...

We tested the accuracy of an atmospheric correction method that depends on clear water bodies to infer solar and atmospheric parameters for radiative transfer equations by measuring the reflectance signature of four prominent south Texas rangeland plants with the Earth Resource Technology (LANDSAT) satellite multispectral scanner (MSS) and a ground-based Exotech Model 20 spectroradiometer. The ...

Preference value means livestock preference to eat some plants relative to other plants or species. Accordingly, by studying the preference values, the range managers could determine the rangelands grazing capacity to achieve the optimum performance of livestock and to guarantee the stability of rangeland ecosystem. The objective of this study was to determine the preference value of perennial ...

Increasing shrub density hinders cattle raising in central Argentina rangelands. While roller-chopping and hand-cutting are used to remove shrubs make land accessible for grazing, studies on the effects of these practices ecosystem composition, structure functioning scarce. We assessed impact removal (a) vegetation cover, species richness diversity (b) green biomass seasonal phenological dynami...

— This paper contributes to the debate over land tenure in rural China by extending its spatial coverage to the country’s extensive rangeland regions. Key characteristics of pastoral tenure, identified from field appraisals in western China, include group tenure and fuzzy boundaries. Although these characteristics give rise to efficiency concerns, from a new institutional economics perspective ...

Rangeland ecosystems typify physical systems having an incomplete causal theory. This paper describes CARMA, a system for rangeland pest management advising that uses model-based matching and adaptation to integrate case-based reasoning with modelbased reasoning for prediction in rangeland ecosystems. An ablation study showed that removing any part of the CARMA’s model-based knowledge dramatica...

For several decades, many grassland bird species have been declining in abundance throughout the Midwest and Great Plains regions of the United States, possibly due to loss of natural grassland habitat and increasing urbanization. I used 20 years of data from the North American Breeding Bird Survey to identify increasing, decreasing, and stable populations of 36 grassland-nesting bird species. ...