Showing papers in "Journal of Arid Environments in 2007"

TL;DR: In this paper, the linear relationship of Log e Rainfall with Net Primary Production (NPP) and NDVI was calculated for every pixel and the RESTREND method showed promising results at a national scale and in the Limpopo Province, where negative trends were often associated with degraded areas in communal lands.

TL;DR: In this paper, the authors analyzed time series of annual rainfall, number of rainy-days per year and monthly rainfall of 20 stations to assess climate variability in arid and semi-arid regions of Iran.

TL;DR: In this article, the impact of exclosures on soil properties, and relate the age of ex-closures to their effectiveness in improving soil chemical and physical properties was investigated.

TL;DR: The colour analysis showed a high L* value and the chromatic co-ordinates were in the yellow-greenish spectrum, and the use of isopropyl alcohol is recommended in ratio 1:3, since its commercial value is lower in comparison with ethanol.

TL;DR: The data clearly indicate that the seeds of halophytes particularly S. fruticosa could be used as a source of oil for human consumption.

TL;DR: In this article, an image analysis approach for estimating fractional cover of green and senescent vegetation using very high-resolution ground photography, and to compare image-based estimates with line-point-intercept (LPI) measures.

TL;DR: In this article, the authors performed simple linear regressions between vegetation cover and biomass for the dominant species and life forms (shrubs: Mulinum spinosum, Senecio filaginoides, and Adesmia campestris; grasses: Poa ligularis, Stipa speciosa, and stipa humilis).

TL;DR: In this paper, a characterization of the flora of the Nao Me Deixes Reserve in Ceara State, Brazil (4°49′34″S, 38°59′09″W, at 210m a.s.

TL;DR: In this article, the authors evaluated whether plant selection by the Mapuche is influenced by environmental constraints and found that the use of wild plants is primarily based on the utilization of species belonging to the nearest ecological environments that have both therapeutic and dietary functions.

TL;DR: In this article, the adsorption and movement of applied K+ in columns of sandy soil were examined, and the results showed that the amount of K+ leached increased as Ca 2+ concentration increased.

TL;DR: In this article, a strategy was developed to investigate the spatial distribution of biological soil crusts by coupling remote sensing data and field measurements in the Gurbantunggut Desert.

TL;DR: In this article, a brief introduction to the physical environment of Namaqualand as well as an overview of patterns of plant diversity is provided, where the authors provide a brief overview of the plant diversity in the region.

TL;DR: In this paper, the authors investigated the relationship between water infiltration rate and soil compaction in desertification models and found that water infiltration is associated with the recovery from livestock-induced ground compaction.

TL;DR: In this paper, a downward trend from North to South was observed in temperature, the onset and the duration of the rainy season, indicating that climate-wise crop production is only possible during 5 months in the north and less than 4 months in south.

TL;DR: In this article, the authors used moisture Bowen ratio flux tower data and the enhanced vegetation index (EVI) from the moderate resolution imaging spectrometer (MODIS) on the Terra satellite to measure and scale evapotranspiration (ET) over sparsely vegetated grassland and shrubland sites in a semiarid watershed in southeastern Arizona from 2000 to 2004.

TL;DR: In this paper, the impacts of sustained heavy grazing in six vegetation types across an altitudinal and rainfall gradient in the Kamiesberg mountain range in Namaqualand were explored across the fence separating the Leliefontein communal area and surrounding privately owned farms.

TL;DR: In this article, the nature and importance of mined soils, topsoils, soil nutrients, landscaping, seedbanks, seeding, transplantation, and the interactions between these and other factors are evaluated in the context of this semi-arid environment and the prevailing mining practices.

TL;DR: A review of previous studies on the Kalahari soils combined with new results from recent analyses of physical (mostly hydraulic) and biogeochemical properties of the soil can be found in this article.

TL;DR: In this paper, the contribution of airborne Saharan dust to soil development in northeastern Gran Canaria was quantified using aeolian dust collected weekly at different altitudes and distances from the coast during a year in a series of collection plots.

TL;DR: The authors used the concept of ecological revolutions to explain the environmental history of Namaqualand, from the advent of pastoralism 2000 years BP, to colonial settlement in the 18th century and finally to the recent trend of de-agrarianization from the middle of the 20th century.

TL;DR: A comparative analysis of the effects of water stress on leaf respiration rates and carbon balance in a wide variety of Mediterranean species with different growth forms and evolutionary history suggested that decreased respiration is part of a systemic metabolic response, which occurs under conditions where drought severely restricts CO 2 availability inside leaves.

TL;DR: In this article, two deciduous shrub species with different morphologies (Tamarix spp and Haloxylon ammodendron Bge) were studied at an oasis-desert ecotone in South Junggar Basin.

TL;DR: In this article, the authors provided an analysis of vegetation and environment relationships in the Alxa Plateau of Inner Mongolia, China, using two-way indicator species analysis (TWINSPAN) techniques.

TL;DR: In this paper, quantile regressions revealed that droughts worsened in Hwange National Park (Zimbabwe) during the course of the 20th century, a change that would not have been detected using simple linear regression.

TL;DR: In this article, the authors quantified long-term trends in atmospheric nitrogen deposition and estimated its impact on plant community structure in the northern Chihuahuan desert of Central New Mexico, USA.

TL;DR: In this article, soil carbon stock was estimated in the 0-25 and 0-100 cm soil depths of arid and semi-arid regions of Rajasthan, where the surface horizon (0-25 cm) stored 31% of the soil inorganic carbon.

TL;DR: In this paper, the authors show that practices of a diversity of livestock keepers on the Leliefontein Commons of Namaqualand are at odds with this viewpoint: access to rangeland and its use are structured by collective norms and concerns regarding both the sharing of resources and their long-term sustainability.

TL;DR: In this article, a number of field experiments were conducted from 1986 to 2003 to investigate the dynamics of soil physical and chemical properties as well as vegetation succession characteristics during the grassland desertification process under sheep grazing.

TL;DR: The effect of light and temperature and addition of gibberellic acid (GA 3 ) in the germination of seeds of Trichocereus terscheckii was evaluated in order to provide information about germination requirements which could be use for conservation studies.

TL;DR: The soil mantle in Namaqualand is immature in terms of weathering and despite or even because of this, the diversity and spatial variability of soil physical and chemical properties is exceptionally high and could be fundamental in governing biodiversity and ecosystem function.