Climate change and direct human land - use pressure are likely to have synergistic impacts on desert ecosystems and species that may be offset, at least partly,
by vegetation productivity and carbon sequestration gains due to rising atmospheric CO2.
Not exact matches
Vegetation biomass,
productivity, and the competitive abilities of different plant types are all influenced
by climate and atmospheric CO2.
By «ecosystem change», we mean changes in some or all of the following: the number and types of organisms present; the ecosystem's physical appearance (e.g., tall or short, open or dense
vegetation); the functioning of the system and all its interactive parts, including the cycling of nutrients and
productivity.
Double CO2 climate scenarios increase wildfire events
by 40 - 50 % in California (Fried et al., 2004), and double fire risk in Cape Fynbos (Midgley et al., 2005), favouring re-sprouting plants in Fynbos (Bond and Midgley, 2003), fire - tolerant shrub dominance in the Mediterranean Basin (Mouillot et al., 2002), and
vegetation structural change in California (needle - leaved to broad - leaved trees, trees to grasses) and reducing
productivity and carbon sequestration (Lenihan et al., 2003).
However, dry - spell duration and warming trend effects on
vegetation productivity may be at least partly offset
by rising atmospheric CO2 effects on plants (Bachelet et al., 2001; Thuiller et al., 2006b), leading to sometimes contrasting projections for deserts that are based on different modelling techniques that either incorporate or ignore CO2 - fertilisation effects.
Further, the United Nations Convention to Combat Desertification (UNCCD) defines land degradation as a reduction or loss in arid, semi-arid, and dry sub-humid areas of the biological or economic
productivity and complexity of rain - fed cropland, irrigated cropland, or range, pasture, forest and woodlands resulting from land uses or from a process or combination of processes, including those arising from human activities and habitation patterns, such as: (i) soil erosion caused
by wind and / or water; (ii) deterioration of the physical, chemical, and biological or economic properties of soil; and (iii) long - term loss of natural
vegetation.
The United Nations Convention to Combat Desertification defines land degradation as a reduction or loss in arid, semi-arid, and dry sub-humid areas, of the biological or economic
productivity and complexity of rain - fed cropland, irrigated cropland, or range, pasture, forest, and woodlands resulting from land uses or from a process or combination of processes, including processes arising from human activities and habitation patterns, such as (i) soil erosion caused
by wind and / or water; (ii) deterioration of the physical, chemical and biological or economic properties of soil; and (iii) long - term loss of natural
vegetation.