Showing papers in "Journal of Arid Environments in 1981"

TL;DR: This paper examined the shape characteristics of 21,600 individual sand grains from a variety of world dune areas and found that true roundness is relatively rare, that different ergs have different grain roundness characteristics, that smaller grains tend to be more angular and that position on a dune seems to be an unimportant control of grain shape.

TL;DR: Field observations over a seven-year period at a desert scorpion community near Palm Springs, California and less intensively at other locales provided information on natural predators of scorpions.

TL;DR: The availability of Zizyphus during the late spring, summer and fall is the primary reason why the gazelle population in this region is so highly productive, and productivity is enhanced by the plant's food and cover characteristics.

TL;DR: In this article, a comparison is made between collections of Collembola from two arid areas on different continents, Africa and Australia, and the collections showed close similarities in taxonomic composition.

TL;DR: Dehydration was associated with intensification of mechanisms which would reduce water demand, and P. namaqua appears to drink only every 3–5 days in the wild.

TL;DR: In this article, the amount of soil loss due to wind, the relationship between wind velocity and soil eroded, the particle size distribution of the eroded soil and the nutrients associated with it were determined.

TL;DR: The composition, size, aggregation and morphological characteristics of wind-blown dust particles are examined in this paper, showing that most untreated material lies in the fraction 2-63 µm with a modal value of approximately 20 µ m, but is characterised by coarser grains with surface aggregations of adhering clay size material.

TL;DR: A flock of 84 breeding ewes, 20 yearlings, five rams, 10 breeding goats, one buck and five kids herded in four fenced paddock rangeland at stocking rate of 1·4 ha per ovine unit, near Azizia in Libya, was pen supplemented for 79 days with 0·5 kg of barley grain and Acacia cyanophylla, ad libitum to meet maintenance energy needs and production requirements.

TL;DR: Characteristics of the mosquitoes’ breeding sites and the role played by temporary rainpools in the distribution of mosquitoes across the Negev Desert are discussed and a dispersal mechanism for aquatic desert insects is proposed involving the use of temporary pools as stepping stones to connect the oasis refuges.

TL;DR: The phenological structure of epigeic animal communities was studied using pit-fall traps along an altitudinal transect in the Peruvian desert, indicating a reliance on perennials for food and shelter rather than on unpredictable annuals.

TL;DR: Whereas the forest and woodland tarantulas show a tendency to be active in light, the scorpions and scolopendras are nocturnal, and the possible ecological significance of these observations is discussed.

TL;DR: The central Australian and southern Kalahari dunefields resemble each other closely in climate and geomorphology, and there are parallels in soil patterns, vegetation structure and plant life-forms, and the herbivorous fauna.

TL;DR: Stabilisation of dunes led to approximately a 200-fold increase in the microbiological population, and the population of fungi, bacteria, actinomycetes, Azotobacter and nitrifying bacteria in stabilised dunes were higher than in unstabilisation dunes.

TL;DR: Four species of Indian desert rodents have been found to have basal metabolic rates lower than the values expected from the metabolic rate-body weight relationship for mammals.

TL;DR: The distribution, population structure and behaviour of agamid lizards at Nsukka during January and early February 1981 are described in this article, where the animals were almost always found near buildings, trees, rubble and fallen logs etc.

TL;DR: Rapid germination and higher oil and protein content of seed make the domesticated P. parviflora superior to the wild form as a crop, and shows promise as an oilseed crop for the Sonoran Desert and possibly for other arid regions.

TL;DR: In constant darkness, the onset of locomotory activity in the nocturnal desert beetle P. grandis free-ran with an advancement of about 1 hour–1 hour 10 min per day despite temperature changes in the range 22.5–16.5°C, although the circadian clock continued to free-run.

TL;DR: Comparisons were made between the germination responses to temperature of freshly harvested seeds of four populations of V. encelioides and R. nervosus, finding the latter shows wide ecological amplitude with regard to its germination temperature responses and may extend the distribution of the species into warmer regions.

TL;DR: In this paper, the authors studied the role of water erosion, water transportation, sedimentation and sedimentation in the Nile system in terms of the amount of water present, its contribution to underground water, sediment discharge, chemical denudation, soil erosion and total denudeation.

TL;DR: The nature of the sediments and of the flora of the Late Cretaceous of north-western North America suggests that salt glands would have been essential to hadrosaurs, which fed on harsh terrestrial vegetation growing in a salt-rich environment.

TL;DR: Nocturnal and burrowing behaviour were noted to be the most important adaptations in surviving the rigorous conditions of the arid pan and other adaptations such as the big ears and eyes and the animals’ freezing behaviour were believed to be effective predator avoidance mechanisms.

TL;DR: It seems that the explanation for the inverse relationship between physiological traits of water economy and the geographical distribution is related to the different habitats with which the two species are associated.

TL;DR: A national land reform was implemented, pasturelands were nationalized, tribal leaders were removed from tribal affairs, and the government controlled land use and migrations in Iran in the 1960s and 1970s.