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Chejara VK, Kriticos DJ, Kristiansen P, Sindel BM, Whalley RDB & Nadolny C (2010). The current and future potential geographical distribution of Hyparrhenia hirta. Weed Research 50, 174–184. Hyparrhenia hirta is a pasture grass that has become highly invasive in several parts of the world, including Australia where it has become a serious environmental weed in recent decades. Knowledge of the likely potential distribution and relative abundance of this invasive species, under current and future climate scenarios, will help biosecurity and weed control authorities to plan better strategies to manage the invasion. The CLIMEX modelling package was used to investigate the impacts of climate change on the potential global distribution of H. hirta, based on eco-physiological data. The worldwide potential distribution of H. hirta under current climatic conditions is vast and far greater than the current distribution, with suitable climate conditions extending over much of the tropics and subtropics. Under future climate scenarios, the range of H. hirta is likely to expand into areas currently too cold for its survival and contract from areas that are projected to become hotter and drier under climate change. The effects of likely climatic scenarios on the global potential distribution of H. hirta are sufficiently great that they should be considered routinely in strategic control plans for biotic invasions. Changes in the potential range of an invasive species such as H. hirta, under global warming scenarios, will mean that it could invade new jurisdictions. Knowledge of this emerging threat could help to formulate effective prevention, surveillance and response measures in these presently marginally unsuitable regions. [ABSTRACT FROM AUTHOR]

Investigates the influence of intensive sheep grazing on genotypic differentiation on native pasture grasses Danthonia. Redistribution of plant nutrients within paddocks grazed by Merino sheep; Increase in inflorescence production; Variation of environmental conditions on sheep camps.

This article presents a study, in which the distribution and percent frequency of the 13 species and one variety of Danthonia recorded on the New England Tablelands, Australia, were examined in a survey of 110 predominantly pastoral sites. The relationships between site factors and the presence and percent frequency of the different Danthonia species were subjected to canonical correlation analysis. Individual species were found to have particular sets of environmental factors associated with their distribution and percent frequency; a fact not well recognized in the past.

Determines the requirements for optimal germination and establishment of Nitraria billardieri. Removal of the saline outer pericarp during digestion; Susceptibility of N. billardieri to competition from cool season annual species; Effect of leaching on germination.

Focuses on the biology and autecology of Nitraria billardieri throughout its distribution range. Subdivision of Nitraria into two sections; Tendency of Nitraria to become a conspicuous element of the vegetation on heavily grazed areas; Potential use of N. billardieri in arid and semi-arid zones of Australia.