Showing papers in "Journal of Arid Environments in 1994"

TL;DR: In the semi-arid and arid Magisterial (administrative) districts (n = 45) in the Cape Province, South Africa, there has been a mean 44·4 ± 14·6% (S.D.) reduction in the stocking rates of domestic livestock over the period 1911-81 as discussed by the authors.

TL;DR: The promotion of more lesser-known species in planting programmes would help to conserve the valuable diversity in both Acacia and Prosopis.

TL;DR: Nabkhas near Mopti in Mali, West Africa have formed as a result of continued cultivation coupled with grazing during periods of severe drought as mentioned in this paper, and the dunes are elongate and average 0·57 m high, 3·45 m wide and 5·45m long.

TL;DR: The opportunity and need for basic and applied research in prickly pear, oriented to improving fruit quality, adaptability and the industrial transformation of both vegetative and reproductive parts, is discussed.

TL;DR: An index of climatic heterogeneity (reflecting the diversity of conditions suitable for plant growth) and measures of rainfall evenness throughout the year, emerged as the strongest predictors of species richness and growth form diversity.

TL;DR: In this article, a series of experiments were undertaken to investigate the role of cryptogams in erosion processes on a red earth soil in semi-arid eastern Australia, and the results indicated that, under natural rainfall conditions, there is a continual transfer of fine material and adsorbed nutrients away from areas of low cryptogam cover.

TL;DR: The data pointed to marked competition between the herbivores, with sheep impacting more on kangaroos when pasture conditions began to deteriorate, and a decline of perennial shrubs in these arid rangelands was considered probable.

TL;DR: In this article, pitfall traps were used to study tenebrionid species composition and activity level in two sandy (dune and stabilized sand field) and four compact soil (wadi, north and southfacing slopes, and loess plain) habitats in the Negev Desert Highlands, Israel.

TL;DR: The results suggest that the pattern of water use by grasses and shrubs in shrublands may be dependent upon strategies to counteract water stress and the phenological patterns developed by species within each life form.

TL;DR: In this article, the authors investigated the relationship between vegetation composition and distance from artificial watering points in six habitats in the Kalahari Gemsbok National Park, and found that although changes in plant species composition occurred in the six different habitats, they were not related to the presence of artificial water points.

TL;DR: It is concluded that the anthophilous insect fauna is dominated by generalist foragers, and most flower/insect associations are not exclusive and frequently overlap.

TL;DR: The extent and intensity of aeolian processes in the Kelso geomorphic system of the Mojave Desert have varied in a complex way in time and space as mentioned in this paper, and geomorphic, stratigraphic, and sedimentologic studies allow the identification of areas of relict, dormant, and active dunes.

TL;DR: It seems that ventilation of the O. transvaalensis colony does not play a significant role in the regulation of colony temperature, and other mechanisms, such as free convection within the colony, or forced ventilation by external winds, may play a minor and secondary role in translocating air inside the colony.

TL;DR: Disconnected peripheral achenes were found to germinate to a higher level in comparison with achene from the peripheral and sub-peripheral whorls which were disconnected shortly before the start of the germination experiments.

TL;DR: In this paper, rates of soil loss were determined using erosion pins on a severely eroded surface in a small (19km 2) arid rangelands catchment in western New South Wales, Australia, over a 10-year period.

TL;DR: Aeolian-climatic thresholds are quantified using time sequence analysis of 1948-87 aeon and climatic data from the Hanford Site, south-central Washington.

TL;DR: Adult desert rams were used to evaluate the effects of changing the watering regime from free intake (control) to every 24, 48 or 72h, which results in adjustments in water and heat balance and induces moderate changes in blood metabolites and endocrine responses.

TL;DR: According to long-term records of a wider selection of species, the persistence of temperate-zone spring flowering patterns was apparent in one section of Acacia, and the same patterns were also more common in shorter-lived species.

TL;DR: The Coleoptera Tenebrionidae of a sandy Tyrrhenian beach (Burano, GR, Italy) was examined by means of bimonthly surveys carried out between March 1991 and January 1992 using two different methods of capture: pitfall traps for surface-active animals, and sieves for those that burrow in the sand.

TL;DR: Thermal shadows provide refuge for surface foraging termites to avoid high temperatures, indicating adequate temperatures for foraging activity.

TL;DR: Seeds longevity, viability and predation of seeds were studied over 2 years in Aptosimum spinescens, Blepharis grossa, Geigeria alata, G. ornativa, Petalidium setosum and P. variabile and the degree of serotiny was related to life form.

TL;DR: In this article, the relationship of soil water dynamics to arid-land coppice dune/swale topography and associated plants was examined under normal and enhanced precipitation, and the effect of enhanced precipitation on end-of-season soil water storage and profile patterns was negligible.

TL;DR: In this article, the authors proposed a technical review to assess water demand and supply relationships, and to determine the potential for drainage problems, and environmental assessments should be made at existing irrigation projects to determine if subsurface drainage is present or could occur in the future.

TL;DR: In the Vizcaino desert of Baja California, Mexico, the authors found that the proportion of winter to summer rainfall decreases with decreasing latitude, and that subtle climatic differences in arid regions are reflected in the floral composition and chemistry of the soils.

TL;DR: In this article, the spatial variation patterns of soil water content are investigated along a bare soil transect covering a crest-to-crest spacing (about 60 m) in a shifting sand dune area.

TL;DR: In this paper, the geomorphology of the Donana National Park is classified into three morphogenetic systems: aeolian, estuarine and littoral.

TL;DR: In this article, the growth and development of a natural population of the oilseed halophyte Salicornia bigelovii Torr. as affected by environmental factors are analyzed.

TL;DR: It is speculated that a high role of reptiles and arthropods as prey would be a characteristic feature of the vertebrate trophic webs in hot desert environments.

TL;DR: Investigation of the responses of seedlings of three shrub species to water stress by withholding water at different stages of seedling development found hardened seedlings survived the longest and Asteraceous species seedlings were the smallest with respect to root and shoot mass.

TL;DR: In this paper, the authors compare several attributes of a number of harvester ant assemblages of Argentinian Monte desert and Chilean arid zones, two South American arid regions separated by the Andes Mountain Range.