Interpretation of Rock Varnish in Australia: case studies from the arid zone

1990 ◽  
Vol 21 (1) ◽  
pp. 18-32 ◽  
Author(s):  
R. I. Dorn ◽  
D. Dragovich
Keyword(s):  
Case Studies ◽  
Arid Zone ◽  
Rock Varnish

Irrigation in arid lands

1986 ◽  
Vol 316 (1537) ◽  
pp. 261-273 ◽  
Keyword(s):  
Case Studies ◽  
Arid Zone ◽  
Arid Lands ◽  
Demand Characteristic ◽  
Economic Factors ◽  
Water Application ◽  
New Techniques ◽  
Irrigation Demand ◽  
Recent Developments ◽  
Reduced Water

The positive aspects of the high irrigation demand characteristic of arid lands are reviewed, together with the classic dangers of salinization and impeded drainage common to such regions. Both aspects are illustrated by case studies of two very different arid zone demand — irrigation agricultures - those of Egypt and Israel. Atmospheric, crop, soil, hydrologic, and economic factors determining irrigation demand in arid lands are reviewed, with emphasis on the recent developments which have resulted in increased productivity and reduced water application. Finally, a brief account is given of current research which could allow these new techniques to be economically adopted on a much wider scale in the future.

scholarly journals Aflaj’s Irrigation Water Demand/Supply Ratio: Two Case Studies

2006 ◽  
Vol 11 ◽  
pp. 85
Author(s):  
Abdullah Al-Ghafri
Keyword(s):  
Case Studies ◽  
Date Palm ◽  
Arid Zone ◽  
Geographical Location ◽  
Arid Environment ◽  
Irrigation Performance ◽  
Monthly Basis ◽  
Date Palms ◽  
Irrigation Water Demand ◽  
Traditional Irrigation

Due to the geographical location of Oman in an arid zone, agricultural production depends fully on irrigation. The traditional irrigation systems (Aflaj, sing. falaj) supply more than one third of water for agriculture. Falaj is defined in the context of this paper as a canal system which provides water for domestic and agricultural uses. Oman has 3,107 active Aflaj producing about 680 Mm3 of water per year. The main objective of this study was to estimate the irrigation performance of Aflaj in Oman. Falaj al-Dariz and al-Nujaid were chosen as case studies. Both Aflaj are located in an extremely arid environment, where the rainfall is low and evapotranspiration is high. The study utilized an approach to estimate the irrigation performance of Aflaj by considering the falaj as a single unit of irrigation. The irrigation demand/supply ratio (D/S) was used in the analysis as a tool of evaluation. Date palm, the dominant crop irrigated by Aflaj, was selected for the analysis. In falaj al-Dariz the date palms were slightly under irrigated on a yearly basis. On a monthly basis, in winter, the D/S was below 0.6 and in summer it was above 1.0. On the other hand, falaj al-Nujaid was supplying too much water than the date palms needed all round the year. In winter the D/S ratio was as low as 0.25. Even in summer, the D/S ratio did not much exceed 1.0. 

Biogeomorphology at the micro-scale: biogeochemical weathering of rock surfaces in the cold and warm deserts

2020 ◽  
Author(s):  
Andrea Zerboni
Keyword(s):  
Case Studies ◽  
Arabian Peninsula ◽  
Micro Scale ◽  
Rock Varnish ◽  
Endolithic Communities

<p><span>Biogeochemical weathering of stable rock surfaces in warm and cold deserts is a notable biogeomorphological process, which contribute to mineralogical transformation of rock constituents and rock disaggregation. Endolithic microorganisms (mostly bacteria, fungi and lichens) play a major role in controlling the destabilization and rejunevation of rock surfaces; but occasionally, biofilms can stabilize rock surfaces. In most of the casis, endolithic communities precipitates byproducts (e.g. oxalates) contributing to enhance discotnituity and promoting exfoliation and disaggregation. On the contrary, rock varnish can develop as an external crust protecting the underliyng rock from erosion and dissolution. In this contribution, a number of case-studies of fossil and active examples of biogeochemical weathering from warm deserts of Africa and Arabian peninsula and from Antarctica are considered. The comaprison of evidence suggests a highly differentiate –  and occasioanlly surprisingly – array of effects of endolithic communities on rock surfaces.</span></p>

scholarly journals Predation by snakes thwarts trial reintroduction of the Endangered woma pythonAspidites ramsayi

Oryx ◽  
2011 ◽  
Vol 45 (4) ◽  
pp. 505-512 ◽  
Author(s):  
J. L. Read ◽  
G. R. Johnston ◽  
T. P. Morley
Keyword(s):  
Case Studies ◽  
Arid Zone ◽  
South Australia ◽  
Lessons Learned ◽  
Ecosystem Recovery ◽  
Potential Value ◽  
Central Australia

AbstractCase studies of well-documented snake reintroductions are limited, despite their potential value for conservation and ecosystem recovery. The Endangered womaAspidites ramsayiis a large boid snake that has declined considerably and is now threatened throughout much of central Australia. We describe a trial release of captive-bred womas into the feral predator-free Arid Recovery Reserve in northern South Australia. All of the reintroduced womas were killed within 4 months, with predation by the mulga snakePseudechis australisconfirmed or implied in all cases. Lessons learned for the conditioning of captive-bred snakes for wild release and the role of the mulga snake in structuring Australian arid-zone snake assemblages are discussed.

Corporate Sustainability: Challenge to Managerial Orthodoxies

2003 ◽  
Vol 9 (1) ◽  
pp. 2-11 ◽  
Author(s):  
Dexter Dunphy
Keyword(s):  
Case Studies ◽  
Corporate Sustainability ◽  
Central Place ◽  
Marked Contrast ◽  
Sustainability Management

ABSTRACTThis paper addresses the issue of corporate sustainability. It examines why achieving sustainability is becoming an increasingly vital issue for society and organisations, defines sustainability and then outlines a set of phases through which organisations can move to achieve increasing levels of sustainability. Case studies are presented of organisations at various phases indicating the benefits, for the organisation and its stakeholders, which can be made at each phase. Finally the paper argues that there is a marked contrast between the two competing philosophies of neo-conservatism (economic rationalism) and the emerging philosophy of sustainability. Management schools have been strongly influenced by economic rationalism, which underpins the traditional orthodoxies presented in such schools. Sustainability represents an urgent challenge for management schools to rethink these traditional orthodoxies and give sustainability a central place in the curriculum.

Short-Form Application of the Screening Test of Spanish Grammar and the Northwestern Syntax Screening Test to Latino Children

1978 ◽  
Vol 9 (4) ◽  
pp. 220-235
Author(s):  
David L. Ratusnik ◽  
Carol Melnick Ratusnik ◽  
Karen Sattinger
Keyword(s):  
New York ◽  
Case Studies ◽  
Metropolitan Area ◽  
Screening Test ◽  
Normative Data ◽  
Short Form ◽  
Latino Children ◽  
Data Application ◽  
York Metropolitan Area ◽  
Multiple Regression Technique

Short-form versions of the Screening Test of Spanish Grammar (Toronto, 1973) and the Northwestern Syntax Screening Test (Lee, 1971) were devised for use with bilingual Latino children while preserving the original normative data. Application of a multiple regression technique to data collected on 60 lower social status Latino children (four years and six months to seven years and one month) from Spanish Harlem and Yonkers, New York, yielded a small but powerful set of predictor items from the Spanish and English tests. Clinicians may make rapid and accurate predictions of STSG or NSST total screening scores from administration of substantially shortened versions of the instruments. Case studies of Latino children from Chicago and Miami serve to cross-validate the procedure outside the New York metropolitan area.

Case Studies for Telepractice in AAC

2014 ◽  
Vol 23 (1) ◽  
pp. 42-54 ◽  
Author(s):  
Tanya Rose Curtis
Keyword(s):  
Service Delivery ◽  
Case Studies ◽  
Eye Gaze ◽  
Cognitive Impairments ◽  
Perceived Barriers ◽  
Computer Experience ◽  
Access Methods ◽  
Complex Communication Needs ◽  
Barriers To Service ◽  
Communication Needs

As the field of telepractice grows, perceived barriers to service delivery must be anticipated and addressed in order to provide appropriate service delivery to individuals who will benefit from this model. When applying telepractice to the field of AAC, additional barriers are encountered when clients with complex communication needs are unable to speak, often present with severe quadriplegia and are unable to position themselves or access the computer independently, and/or may have cognitive impairments and limited computer experience. Some access methods, such as eye gaze, can also present technological challenges in the telepractice environment. These barriers can be overcome, and telepractice is not only practical and effective, but often a preferred means of service delivery for persons with complex communication needs.

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