Articles de revues : « Thal Desert »

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Abbas, Muhammad Wasim, Mian Saeed Ahmad et Imran Ahmad. « Settlement of the Thal Desert (1949-1969) ». Global Political Review V, n^o II (30 juin 2020) : 34–45. http://dx.doi.org/10.31703/gpr.2020(v-ii).04.

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The British introduced canal colonies system in Punjab province and Thal Canal Colony is one of them. The work on Thal Canal Colony had started in 1939 and could not be completed till the partition of the Subcontinent. Newly established state of Pakistan planned to complete the Thal Canal Colony Project on the emergency basis not only to solve the refugee problem but also to settle the people whose lands were destroyed by river action or due to waterlogging and saline. The main objective of this research work is to study the whole settlement process of the Thal in detail. The historical research approach has been applied, and data has been collected through primary and secondary sources. The Government of Pakistan not only completed the settlement process successfully but also provided all modern facilities of life to the new settlers.

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Liang, Wendong, Eduardo Garzanti, Sergio Andò, Paolo Gentile et Alberto Resentini. « Multimineral Fingerprinting of Transhimalayan and Himalayan Sources of Indus-Derived Thal Desert Sand (Central Pakistan) ». Minerals 9, n^o 8 (26 juillet 2019) : 457. http://dx.doi.org/10.3390/min9080457.

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As a Quaternary repository of wind-reworked Indus River sand at the entry point in the Himalayan foreland basin, the Thal Desert in northern Pakistan stores mineralogical information useful to trace erosion patterns across the western Himalayan syntaxis and the adjacent orogenic segments that fed detritus into the Indus delta and huge deep-sea fan throughout the Neogene. Provenance analysis of Thal Desert sand was carried out by applying optical and semi-automated Raman spectroscopy on heavy-mineral suites of four eolian and 11 fluvial sand samples collected in selected tributaries draining one specific tectonic domain each in the upper Indus catchment. In each sample, the different types of amphibole, garnet, epidote and pyroxene grains—the four dominant heavy-mineral species in orogenic sediment worldwide—were characterized by SEM-EDS spectroscopy. The chemical composition of 4249 grains was thus determined. Heavy-mineral concentration, the relative proportion of heavy-mineral species, and their minerochemical fingerprints indicate that the Kohistan arc has played the principal role as a source, especially of pyroxene and epidote. Within the western Himalayan syntaxis undergoing rapid exhumation, the Southern Karakorum belt drained by the Hispar River and the Nanga Parbat massif were revealed as important sources of garnet, amphibole, and possibly epidote. Sediment supply from the Greater Himalaya, Lesser Himalaya, and Subhimalaya is dominant only for Punjab tributaries that join the Indus River downstream and do not contribute sand to the Thal Desert. The detailed compositional fingerprint of Thal Desert sand, if contrasted with that of lower course tributaries exclusively draining the Himalaya, provides a semi-actualistic key to be used, in conjunction with complementary provenance datasets and geological information, to reconstruct changes in paleodrainage and unravel the relationship between climatic and tectonic forces that controlled the erosional evolution of the western Himalayan-Karakorum orogen in space and time.

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Shaheen, H., R. Qureshi, A. Akram et M. Gulfraz. « Inventory of Medicinal Flora from Thal Desert, Punjab, Pakistan ». African Journal of Traditional, Complementary and Alternative Medicines 11, n^o 3 (10 juillet 2014) : 282. http://dx.doi.org/10.4314/ajtcam.v11i3.39.

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FARAZ, A., A. WAHEED, M. YAQOOB et R. H. MIRZA. « Camel Production Profile in Desert Ecosystem of Thal, Punjab ». SINDH UNIVERSITY RESEARCH JOURNAL -SCIENCE SERIES 51, n^o 01 (12 mars 2019) : 45–52. http://dx.doi.org/10.26692/sujo/2019.01.09.

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Khan, Muhammad S., et Muhammad R. Z. Khan. « A new skink from the Thal Desert of Pakistan ». Asiatic herpetological research. 7 (1997) : 61–67. http://dx.doi.org/10.5962/bhl.part.18856.

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Abbas, Muhammad Wasim, Imran Ahmad et Muhammad Farooq Akbar Leghari. « Agricultural Development under Thal Development Authority (1949-69) ». Global Regional Review V, n^o II (30 juin 2020) : 80–89. http://dx.doi.org/10.31703/grr.2020(v-ii).09.

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The Thal is a desert in the west of Punjab province of Pakistan having an area of five million-acre. It had been a barren piece of land for centuries. West Pakistan Government not only provided canal water to almost 2.1 million acres of the region but also developed the area from 1949 to 1969. The agricultural development of the Thal region carried out by the Thal Development Authority is a historical event in the history of Pakistan. This study is historical research and data has been collected through primary and secondary sources. This paper will highlight the agricultural development of the region in detail and its socio-economic effects on the masses as well.

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Abbas, Muhammad Wasim. « A Study of Settlement of Refugees in the Thal Desert (1947-1969) ». Pakistan Social Sciences Review 4, n^o II (30 juin 2020) : 164–76. http://dx.doi.org/10.35484/pssr.2020(4-ii)14.

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Farooq, Umar, Munir Ahmad et Ikram Saeed. « Enhancing Livestock Productivity in the Desert Ecologies of Pakistan : Setting the Development Priorities. » Pakistan Development Review 48, n^o 4II (1 décembre 2009) : 795–820. http://dx.doi.org/10.30541/v48i4iipp.795-820.

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Livestock is now sharing by more than 53 percent of total agricultural value added in Pakistan. Identifying and developing the potential areas of livestock production is part of the overall development strategy for this sector while rural poverty alleviation is a major concern of Pakistan’s overall development policy. Our major livestock production systems are grazing, stall-fed and grazing-cum-stall-fed based. Grazing based livestock farming is economical and customary system in mountainous, rainfed, deserts and salinity affected areas. The livestock herders of desert areas deserve special attention of the policy-makers because of their most deprived living conditions as majority is living below poverty line by all poverty measuring standards. The present study is aimed to generate an updated synthesis based on empirical knowledge about status of livestock farming in desert ecologies of Pakistan. The results show that the average herd sizes maintained by the herders is fairly large to cover losses due to drought, disease and other epidemics. The human and physical capital endowments of the farmers are generally poor. Other common characteristics are: major dependence on natural vegetation with limited supply of fodder, more physical exertion of animals during grazing, poor animal health, practicing natural method of breeding, low milk and meat productivity, highly limited livestock and milk marketing opportunities, etc. The stall feeding is mainly composed of dry stalks and straws of different crops along with a small quantity of food grains. On marketing side, because of location and lack of infrastructure support, milk marketing opportunities are meager, therefore, it is converted into desi ghee—a value added and preserved form which is sold in nearby town markets. In marketing of live animals, the farmers are always exploited by beoparies. On average herd size, the net monthly income in Cholistan desert from cattle (for milk), sheep and goats farming (for meat purpose) was Rs 10128, Rs 990 and Rs 508, respectively; for Thal desert the corresponding estimates were Rs 457, Rs 359 and Rs 552, respectively; and for Tharparkar, the corresponding estimates are Rs 918, Rs 3221 and Rs 331, respectively. There is a strong need of prioritising development efforts for desert ecologies. High priority areas include efforts for increasing availability of rangeland vegetation and green fodder, improvement in the genetic potential of local livestock breeds, provision of more efficient livestock health coverage, and establishment of milk collection centres of milk processing plants. The low priority areas include designing regulatory framework for milk and livestock marketing, programs for human capacity building, facilitating through institutional credit, and different incentives for the veterinary staff posted in such areas. JEL classification: Q130, Q190, Q200 Keywords: Desert, Tharparkar, Thal, Cholistan, Livestock Farming, Livestock Feeding Patterns, Feed Composition, Livestock Trade Intensity, Priority Setting.

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Saddiqi, Hafiz Abubakar, Abdul Jabbar, Zafar Iqbal, Wasim Babar, Zia-ud-Din Sindhu et Rao Zahid Abbas. « Comparitive efficacy of five anthelmintics against trichostrongylid nematodes in sheep ». Canadian Journal of Animal Science 86, n^o 4 (1 décembre 2006) : 471–77. http://dx.doi.org/10.4141/a06-036.

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The efficacy of levamisole, ivermectin and three different preparations of oxfendazole, applied at the recommended rate, were evaluated in flocks of sheep kept at two farms in Thal desert, Pakistan. Sixty animals on each farm were selected randomly on the basis of their weight and egg count of more than 150 eggs per gram of faeces. Three preparations of oxfendazole (fendamex, oxazole, syatamex), levamisole and ivermectin were given to five groups while one untreated group was kept as control. Faecal egg counts, faecal egg count reduction test, postmortem worm count and copro-culture were performed to assess the efficacy of selected anthelmintics. Levamisole and ivermectin preparations reduced (P ≤ 0.05) prevalent species of gastrointestinal nematodes in both flocks. Oxfendazole preparations exhibited low efficacy and some gastrointestinal nematodes (Haemonchus and Trichostrongylus) were suspected for resistance against these preparations, with resistance more pronounced in oxazole followed by systamex and fendamex. It was concluded that all oxfendazole preparations had low efficacy with suspicion for anthelmintic resistance while levamisole and ivermectin had reasonable effectiveness against prevalent gastrointestinal nematodes of sheep kept in Thal desert, Pakistan. Key words: Anthelmintic, resistance, gastrointestinal nematodes, sheep, Pakistan

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Rasool, Faiz, Muhammad Ishaque, Shahid Yaqoob et Asif Tanveer. « CHEMICAL COMPOSITION AND ETHNOBOTANICAL USES OF ACACIA JACQUEMONTII BENTH. IN THE THAL DESERT IN PAKISTAN ». BOIS & ; FORETS DES TROPIQUES 331 (21 juillet 2017) : 67–76. http://dx.doi.org/10.19182/bft2017.331.a31327.

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This study was conducted in 2014 at the department of botany and the nutritional laboratory of Faisalabad University of Agriculture, in order to assess the chem- ical composition of Acacia jacquemontii Benth. and its ethnobotanical uses in local communities of the Thal desert in Pakistan. To determine its chemical com- position, mature leaves and pods of the species were collected in the field and composite samples were prepared. Their chemical composition was then deter- mined for crude protein, fat, fibre, ash, micro and macro-elements, total pheno- lics, flavonoids, total tannins, alkaloids and saponin. An interview schedule was developed to assess ethnobotanical uses of A. jacquemontii by local communities for food, shelter and medicine. Thirteen local people and thirteen Hakims involved in traditional uses were interviewed. Our results showed that the leaves and seeds of the species contained respectively 22% and 33% of crude proteins and 49% and 15% of crude fibre. Fats in the leaves and seeds amounted to 17% and 28%. The leaves contained 0.1% phosphorus, 0.6% potassium, 1.2% calcium, 0.1% sodium and 0.6% magnesium and micro-el- ements: iron (246 ppm), manganese (29.2 ppm), zinc (27.9 ppm) and copper (14.4 ppm). The amounts of alkaloids, flavonoids, saponins, tannins and total phenolics found in the leaves were 5.8, 168, 196, 124 and 137 respectively. Our results for ethnobotanical uses showed that besides using this shrub for shelter- belts, firewood, fodder and medicines, local people have strong religious beliefs, calling A. jacquemontii the ‘shrub of the ghosts’ and believing in its “magic” pow- ers in the practice of necromancy. It was used in the past by Greek practitioners in this area to treat common ailments.

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Biagi, Paolo, Elisabetta Starnini et Zubair Shafi Ghauri. « Mahi Wala 1 (MW-1) : a Mesolithic site in the Thal desert of Punjab (Pakistan) ». Asian Archaeology 3, n^o 1-2 (24 juin 2019) : 1–8. http://dx.doi.org/10.1007/s41826-019-00024-z.

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Shaheen, Humaira, Rahmatuallah Qureshi, Mirza Faisal Qaseem et Piero Bruschi. « The fodder grass resources for ruminants : A indigenous treasure of local communities of Thal desert Punjab, Pakistan ». PLOS ONE 15, n^o 3 (5 mars 2020) : e0224061. http://dx.doi.org/10.1371/journal.pone.0224061.

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Bhatti, Zafar Iqbal, Muhammad Asad Habib et Tamsila Naeem. « Number Marking in English and Thali : A Contrastive Study ». International Journal of English Linguistics 10, n^o 2 (13 février 2020) : 255. http://dx.doi.org/10.5539/ijel.v10n2p255.

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The aim of this paper is to explore the number system in Thali, a variety of Punjabi spoken by natives of Thal desert. There are three number categories singular, dual, and plural but all modern Indo Aryan languages have only singular and plural (Bashir & Kazmi, 2012, p. 119). It is one of the indigenous languages of Pakistan from the Lahnda group as described by Grierson (1819) in his benchmark book Linguistic Survey of India. Layyah is one of the prominent areas of Thal regions. The native speakers of Thali use this sub dialect of Saraiki in their household and professional life. The linguistic boundaries of the present Siraiki belt have changed under different linguistic variational rules as described by Labov (1963), Trudgal (2004), Eckert (2002) and Meryhoff (2008). There are many differences between Thali and Saraiki, on phonological, morphological and orthographical levels. Husain (2017) has pointed out linguistic differences between Saraiki and Lahnda and Thali is one of the popular languages of Lahnda spoken in different parts of Thal regions. According to the local language activists, Thali has been greatly influenced by Saraiki and Punjabi. The lexicon of Thali is composed for 20% of Punjabi, 45% of Saraiki, and 5% of loan words particularly English. Another particularity is that Perso-Arabic characters are used to write Thali. The most distinguishing characteristics of Thali are its parts of speech, word order, case marking, verb conjugation and, finally, usage of grammatical categories in terms of number, person, tense, voice and gender. In this perspective, number marking is the area to focus on noun morphology and exclusively on the recognition of number system in Thali nouns. The analysis of linguistic systems including grammar, lexicon, and phonology provide sound justifications of number marking systems in languages of the world (Chohan & García, 2019).

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Garzanti, Eduardo, Wendong Liang, Sergio Andò, Peter D. Clift, Alberto Resentini, Pieter Vermeesch et Giovanni Vezzoli. « Provenance of Thal Desert sand : Focused erosion in the western Himalayan syntaxis and foreland-basin deposition driven by latest Quaternary climate change ». Earth-Science Reviews 207 (août 2020) : 103220. http://dx.doi.org/10.1016/j.earscirev.2020.103220.

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Anwer, Iqra. « Phytomedicinal Potential of Ethanolic Extracts of Some Trees and Herbs from Thal Desert : in Vitro Assessment of Plant Antioxidants Effects on Human Haematological Attributes ». Bioscience Biotechnology Research Communications 13, n^o 2 (25 juin 2020) : 601–9. http://dx.doi.org/10.21786/bbrc/13.2/36.

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Mahmood Aulakh, Azhar, Ghulam Qadir, Fayyaz Ul Hassan, Rifat Hayat, Tariq Sultan, Motsim Billah, Manzoor Hussain et Naeem Khan. « Desert Soil Microbes as a Mineral Nutrient Acquisition Tool for Chickpea (Cicer arietinum L.) Productivity at Different Moisture Regimes ». Plants 9, n^o 12 (24 novembre 2020) : 1629. http://dx.doi.org/10.3390/plants9121629.

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Drought is a major constraint in drylands for crop production. Plant associated microbes can help plants in acquisition of soil nutrients to enhance productivity in stressful conditions. The current study was designed to illuminate the effectiveness of desert rhizobacterial strains on growth and net-return of chickpeas grown in pots by using sandy loam soil of Thal Pakistan desert. A total of 125 rhizobacterial strains were isolated, out of which 72 strains were inoculated with chickpeas in the growth chamber for 75 days to screen most efficient isolates. Amongst all, six bacterial strains (two rhizobia and four plant growth promoting rhizobacterial strains) significantly enhanced nodulation and shoot-root length as compared to other treatments. These promising strains were morphologically and biochemically characterized and identified through 16sRNA sequencing. Then, eight consortia of the identified isolates were formulated to evaluate the growth and development of chickpea at three moisture levels (55%, 75% and 95% of field capacity) in a glass house experiment. The trend for best performing consortia in terms of growth and development of chickpea remained T2 at moisture level 1 > T7 at moisture level 2 > T4 at moisture level 3. The present study indicates the vital role of co-inoculated bacterial strains in growth enhancement of chickpea under low moisture availability. It is concluded from the results that the consortium T2 (Mesorhizobium ciceri RZ-11 + Bacillus subtilis RP-01 + Bacillus mojavensis RS-14) can perform best in drought conditions (55% field capacity) and T4 (Mesorhizobium ciceri RZ-11 + Enterobacter Cloacae RP-08 + Providencia vermicola RS-15) can be adopted in irrigated areas (95% field capacity) for maximum productivity of chickpea.

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Majeed, Salman, Mushtaq Ahmad, Alamdar Ali, Ashwaq T. Althobaiti, Mohamed Fawzy Ramadan, Omer Kilic, Azize Demirpolat et al. « Pollen Micromorphology among Amaranthaceous Species from Desert Rangeland : Exine Stratification and their Taxonomic Significance ». BioMed Research International 2023 (20 janvier 2023) : 1–20. http://dx.doi.org/10.1155/2023/4967771.

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The aim of the study was to visualize the micromorphology of Amaranthaceous pollen using scanning electron microscopy collected from the Thal Desert. Field collection was conducted from July to September 2021. A total of 14 taxa of the family Amaranthaceae were collected which belong to nine genera. Achyranthes aspera, Aerva javanica, Aerva lanata, Amaranthus graecizans, Amaranthus retroflexus, Amaranthus viridis, Bassia indica, Chenopodium album, Chenopodium ficifolium, Chenopodium murale, Digera muricata, Haloxylon stocksii, Salsola tragus, and Suaeda fruticosa were studied in terms of pollen morphotypes. Pollen were acetolyzed and observed under optical and scanning microscopy. Qualitative and quantitative characters were measured to analyze the pollen to uncover its taxonomic significance. Qualitative characters observed were the shape of pollen in polar and equatorial views; the most frequent shape observed was spheroidal in the polar view, whereas in the equatorial view, prolate spheroidal was the dominant shape. Exine ornamentation is the key characteristic of pollen which is very helpful, and eight different types of ornamentations were observed in collected taxa: smooth sparsely granulate, scabrate-spinulose, microspinulose perforate, microechinate scabrate to metareticulate, granulate, nanospinulate, granulate-spinulose perforate, granulate-perforate echinate, and microechinate perforate. Periporate-type aperture was observed among all taxa. Mesoporia, ektexinous bodies, and tectum features also show variations among Amaranthaceous grains. In quantitative character, A. retroflexus recorded highest in polar view 26.3 μm and the lowest was of C. album 12.2 μm. Highest P/E index ratio was recorded in S. fruticosa (1.12) whereas the lowest for D. muricta (0.94). Exine thickness was highest in S. tragus 2.15 μm and lowest in A. graecizans 0.78 μm. The maximum number of pores was recorded as 32-36 in D. muricata. Artificial taxonomic keys were constructed based on findings that reinforce the importance of the micromorphological ultrastructural diversity of pollen among Amaranthaceous taxa. It was concluded that the descriptions of pollen morphotypes presented greatly contribute to our understanding of desert species identification.

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Kerley, GIH, et WG Whitford. « Desert-Dwelling Small Mammals as Granivores - Intercontinental Variations ». Australian Journal of Zoology 42, n^o 4 (1994) : 543. http://dx.doi.org/10.1071/zo9940543.

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Deserts are, by definition, environmentally similar, and this has lead to hypotheses of convergence in the properties of desert biotic communities as well as the components of these communities. There is considerable evidence for convergence in some characteristics of desert biota, ranging from plant growth forms to the well-known bipedal, nocturnal rodents. One area that has received considerable attention has been granivory by desert rodents, largely because of the effort focused on the North American desert heteromyids, and also because the process of granivory has far-reaching ramifications for desert plant communities. Specific tests for convergence in the impact of rodents as granivores, by means of bait-removal experiments, however, have shown that the high levels of seed removal by rodents in the North American deserts differs from that of rodents in the South American, Australian and South African deserts, where ants are the most important seed harvesters. The only studies to measure the impact of rodents on desert seed fluxes confirm these patterns, with rodents consuming up to 86% of seed production in North American deserts, but less than 1% of seed production in South African deserts. A review of dietary data for desert rodents confirms these trends, with little evidence for the presence of granivores in deserts besides those of North America. A variety of hypotheses have attempted to explain these variations in desert rodent granivory. These include recent extinctions of granivores, that seed burial, low soil nutrients and/or limiting seed production prevented the radiation of granivorous small mammals, and that particular deserts are too young or too recently colonised by rodents for granivorous rodents to have evolved. However, none of these hypotheses are supported by available evidence. Alternative hypotheses suggesting that climate variability may have precluded the development of specialised granivores need to be tested. In particular, more data are needed to confirm these patterns of granivory, and gain an understanding of the effects of Pleistocene and recent desert climate variability on seed production. An alternative perspective suggests that the presence of the heteromyid rodents may explain the high levels of granivory by small mammals in North American deserts. The variability in granivory by small mammals between deserts suggests that deserts will also differ in terms of anti-granivore adaptations of plants, seed fluxes and the mechanisms whereby small mammals coexist.

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Shenbrot, GI, KA Rogovin et EJ Heske. « Comparison of Niche-Packing and Community Organization in Desert Rodents in Asia and North-America ». Australian Journal of Zoology 42, n^o 4 (1994) : 479. http://dx.doi.org/10.1071/zo9940479.

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We compared patterns of species diversity, locomotory morphology, feeding modes, and spatial organisation for rodent communities in four Asian deserts (Kyzylkum, Gobi, ?Thar, Negev) and one North American (Chihuahuan) desert. Deserts were similar in gamma and alpha diversity. A positive relationship between regional species diversity (and biomass) and mean annual precipitation was found. The Asian deserts showed a greater degree of divergence and specialisation between bipedal and quadrupedal forms. The range of feeding modes was similar in deserts on both continents, but the Negev was the only Asian desert in which granivory was as important as in the Chihuahuan. Temperate Asian desert rodents were organised into spatial guilds, separated primarily by characteristics of the soil and perennial vegetation. North American desert rodent species overlapped more extensively in habitat use. The similarities and differences between these deserts can be explained by their biogeographic histories.

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Smalley, Ian, John Marshall, Kathryn Fitzsimmons, W. Brian Whalley et Samson Ngambi. « Desert loess : a selection of relevant topics ». Geologos 25, n^o 1 (1 avril 2019) : 91–102. http://dx.doi.org/10.2478/logos-2019-0007.

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Abstract In discussions on loess, two types are often demarcated: glacial loess and desert loess. The origin of the idea of desert loess appears to lie with V.A. Obruchev who observed wind-carried silt on the Potanin expedition to Central Asia in 1895. It might be considered that desert loess would be defined as loess associated with deserts but it came to be thought of as loess produced in deserts. This led to some controversy as no mechanism for producing silt particles in deserts was readily available. Bruce Butler in Australia in particular cast doubt on the existence of desert-made loess. Butler indicated loess-like deposits in Australia which he called Parna; these are very like loess but the silt sized particles are actually clay mineral agglomerates of silt size- formed in dry lake regions. At the heart of the desert loess discussion is the problem of producing loess material in deserts. It has been suggested that there are no realistic mechanisms for forming large amounts of loess dust but there is a possibility that sand grain impact may produce particle shattering and lead to the formation of quartz silt. This would appear to be a reasonable mechanism for the African deposits of desert loess, but possibly inadequate for the huge deposits in China and Central Asia. The desert loess in China and Central Asia is loess associated with a desert. The material is formed in cold, high country and carried by rivers to the vicinity of deserts. It progresses then from deserts to loess deposit. Adobe ground may be defined as desert loess. Adobe occurs on the fringe of deserts, notably in the Sahelian region of Africa, and in SW USA. The use of adobe in construction represents the major utilization of desert loess in a social context. More understanding of adobe is required, in particular with respect to the adobe reaction, the low order chemical reaction which provides modest cementitious properties, and can be likened to the pozzolanic reactions in hydrating cement systems. The location of loess and loess-like ground on the peripheries of deserts is aided by the observation of the nesting sites of bee-eater birds. These birds have a determined preference for loess ground to dig their nesting tunnels; the presence of nest tunnels suggests the occurrence of desert loess, in desert fringe regions. We seek amalgamation and contrast: ten main topics are considered: words and terms, particles, parna, geotechnical, adobe, people, birds, Africa, Central Asia, Mars. The aim is some large generalizations which will benefit all aspects of desert loess investigation.

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Kidron, Giora J., et Roberto Lázaro. « Are coastal deserts necessarily dew deserts ? An example from the Tabernas Desert ». Journal of Hydrology and Hydromechanics 68, n^o 1 (1 mars 2020) : 19–27. http://dx.doi.org/10.2478/johh-2020-0002.

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AbstractVapor condensation, whether due to dew or fog, may add a stable and important source of water to deserts. This was also extensively assessed in the Negev, regarded as a dew desert. Dew deserts necessitate a large reservoir of vapor, and are therefore confined to near oceans or seas. Yet, examples of such deserts are scarce. Here we try to assess whether the Tabernas Desert in SE Spain can be regarded as a dew desert, and may therefore facilitate the growth of certain organisms that otherwise would not survive the dry season. We analyze some of the abiotic conditions of four relatively dry months (June, July, August, September) in the Tabernas and Negev deserts (with the Negev taken as an example of a dew desert) during 2003–2012. The analysis showed substantially lower values of relative humidity (by 10–13%) in the Tabernas in comparison to the Negev, with RH ≥95% being on average only 0.9–1.1 days a month in the Tabernas in comparison to 9.7–13.9 days in the Negev. Our findings imply that the Tabernas Desert cannot be regarded as a dew desert, suggesting that rain will be the main factor responsible for the food web chain in the Tabernas.

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Jiao, Junfeng, et Mingming Cai. « Using Open Source Data to Identify Transit Deserts in Four Major Chinese Cities ». ISPRS International Journal of Geo-Information 9, n^o 2 (6 février 2020) : 100. http://dx.doi.org/10.3390/ijgi9020100.

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The concept of transit deserts stems from the concept of food deserts. There is substantial research on transit deserts in developed countries. However, there is no known research that has studied this subject in Chinese cities. Using open-source data, this paper identified transit desert areas in four major Chinese cities (Beijing, Shanghai, Wuhan, Chengdu). The results show that: (1) In these four cities, the transit desert areas are mainly concentrated in city centers and hardly occur in any suburban areas, which is very different from the cases in the US. (2) Shanghai has the largest transit-dependent population living in transit deserts, followed by Beijing, Chengdu, and Wuhan. Chengdu has the smallest transit desert areas, followed by Shanghai, Wuhan, and Beijing. (3) An oversized transit-dependent population and incomplete transit systems in these cities might contribute to the transit deserts’ occurrences. (4) Different distribution of population density, traveling preference, and transportation investment policy in Chinese and American cities might contribute to the different findings. By examining transit desert problems in major Chinese cities, this study brought people’s attention to the gap between transit demand and supply in China.

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Port, U., et M. Claussen. « Stability of the vegetation–atmosphere system in the early Eocene climate ». Climate of the Past Discussions 11, n^o 3 (5 mai 2015) : 1551–78. http://dx.doi.org/10.5194/cpd-11-1551-2015.

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Abstract. We explore the stability of the atmosphere–vegetation system in the warm, almost ice-free early Eocene climate and in the interglacial, pre-industrial climate by analysing the dependence of the system on the initial vegetation cover. The Earth system model of the Max Planck Institute for Meteorology is initialised with either dense forests or bare deserts on all continents. Starting with desert continents, an extended desert remains in Central Asia in early Eocene climate. Starting with dense forest coverage, this desert is much smaller because the initially dense vegetation cover enhances water recycling in Central Asia relative to the simulation with initial deserts. With a smaller Asian desert, the Asian monsoon is stronger than in the case with a larger desert. The stronger Asian monsoon shifts the global tropical circulation leading to coastal subtropical deserts in North and South America which are significantly larger than with a large Asian desert. This result indicates a global teleconnection of the vegetation cover in several regions. In present-day climate, a bi-stability of the atmosphere–vegetation system is found for Northern Africa only. A global teleconnection of bi-stabilities in several regions is absent highlighting that the stability of the vegetation–atmosphere system depends on climatic and tectonic boundary conditions.

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Vasar, Martti, John Davison, Siim-Kaarel Sepp, Maarja Öpik, Mari Moora, Kadri Koorem, Yiming Meng et al. « Arbuscular Mycorrhizal Fungal Communities in the Soils of Desert Habitats ». Microorganisms 9, n^o 2 (22 janvier 2021) : 229. http://dx.doi.org/10.3390/microorganisms9020229.

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Deserts cover a significant proportion of the Earth’s surface and continue to expand as a consequence of climate change. Mutualistic arbuscular mycorrhizal (AM) fungi are functionally important plant root symbionts, and may be particularly important in drought stressed systems such as deserts. Here we provide a first molecular characterization of the AM fungi occurring in several desert ecosystems worldwide. We sequenced AM fungal DNA from soil samples collected from deserts in six different regions of the globe using the primer pair WANDA-AML2 with Illumina MiSeq. We recorded altogether 50 AM fungal phylotypes. Glomeraceae was the most common family, while Claroideoglomeraceae, Diversisporaceae and Acaulosporaceae were represented with lower frequency and abundance. The most diverse site, with 35 virtual taxa (VT), was in the Israeli Negev desert. Sites representing harsh conditions yielded relatively few reads and low richness estimates, for example, a Saudi Arabian desert site where only three Diversispora VT were recorded. The AM fungal taxa recorded in the desert soils are mostly geographically and ecologically widespread. However, in four sites out of six, communities comprised more desert-affiliated taxa (according to the MaarjAM database) than expected at random. AM fungal VT present in samples were phylogenetically clustered compared with the global taxon pool, suggesting that nonrandom assembly processes, notably habitat filtering, may have shaped desert fungal assemblages.

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Wilkinson, Toby, Karl W. Butzer, Dirk Huyge, Stan Hendrickx, Timothy Kendall et Ian Shaw. « Review Feature : A review of Genesis of the Pharaohs : Dramatic New Discoveries that Rewrite the Origins of Ancient Egypt, by Toby Wilkinson. London : Thames & ; Hudson, 2002. ISBN 0-500-05122-4 hardback £18.95 ; 208 pp., 87 ills., 25 in colour ». Cambridge Archaeological Journal 14, n^o 1 (avril 2004) : 113–35. http://dx.doi.org/10.1017/s0959774304000095.

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The processes leading to the formation of early state societies remain one of the key topics of archaeological research. Few of these early states are as famous or evocative as that of ancient Egypt, a land of dramatic monuments and terrain, with mysterious and exotic religious practices and a distinctive and exotic iconography. But was Egypt the gift of the Nile, as the Greek historian Herodotus alleged? In this new book, Toby Wilkinson draws attention to a relatively neglected part of the Egyptian landscape: not the fertile river valley, but the deserts which fringe it to east and west. It is here in the deserts, he argues, that the origins of the Egyptian state are to be found. In recent millennia, the deserts have been hostile environments of rock and sand. Go back before 3000 bc, however, and a rather different picture emerges. This different picture is of a desert hinterland peopled by nomadic groups who spent part of their year in the Nile valley. It suggests a more mobile view of Egyptian Predynastic society than has usually been supposed. Desert and valley may have functioned together in a classic pattern of complementarity between contrasting environmental zones, with cattle herds perhaps moved from valley floor to desert in step with the cyclical pattern of the seasons. The specific ingredient which Wilkinson uses to link valley and desert during the fourth millennium bc is rock art. Egyptian rock art has not yet been properly recognized as a rich and important repertoire by specialists in the burgeoning field of rock art as whole. Surveys over more than a century, however, have revealed numerous groups of pecked and engraved images on the desert cliffs and boulders, and recent expeditions (including those by Wilkinson himself) are continually adding to the corpus. The Egyptian desert rock art is generally less well-known than the vivid rock paintings of the central Sahara (such as the famous Tassili frescoes), though it too conveys the image of a greener more habitable landscape. Wilkinson ties specific motifs found in the desert rock art to iconography from the Nile valley during the fourth millennium and later. Yet the linkages and chronologies remain controversial, along with the central hypothesis. Did the desiccation of the savannas lead to the formation of the Egypt, forcing the scattered pastoralist populations to withdraw to a cultivated Nile valley? Was Egypt the gift of the deserts, not the Nile? In this Review Feature the hypothesis is examined by specialists working in Egypt and Nubia, and the reliability of the supporting evidence is assessed.

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Pervaiz, Bushra, Ninghui Li, Muhammad Qasim Manzoor et Muhammad Yaseen. « Socio-Economic Characteristics of Farming Community and Food Security Situation in Punjab, Pakistan ». Journal of Agricultural Science 9, n^o 8 (18 juillet 2017) : 130. http://dx.doi.org/10.5539/jas.v9n8p130.

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Despite the availability of ample food and reasonably low food prices, food insecurity prevailed in many developing countries in 1970s. The paradigm shift in 1980s from supply to demand side of food security underlined the entitlement or access to food as the center of mainstream research. Current study is the findings of the data collected from household level survey regarding socio-economic and food insecurity conditions in the Punjab province of Pakistan. The descriptive analysis and cross tabulation of the household data revealed that household assets, house building material, size of agricultural farms, ownership of tractor, farm livestock were associated with food security conditions of the farming community. The data results also confirmed that the poorer families made major expenditure on the food out of total household expenditure every month. It was also revealed that households in the irrigated regions of Punjab have better entitlement as compared with households surveyed from Thal (desert) and rain-fed regions. The daily consumption of eggs, milk and various forms of meat was found below daily recommended nutritional requirements in most of the households. This study confirms the findings of the earlier surveys made in this regard and highlights the demand side of food insecurity issues in Punjab province of Pakistan. Food security policies in Pakistan should focus entitlement and food access of farming households. The household and farm assets need to be built for reducing vulnerability of poorer farming community to food insecurity in Pakistan.

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Madadin, Mohammed, Rozanna Al-Abdulrahman, Shatha Alahmed, Rana Alabdulqader, Lama Alshehri et Norah Alkathery. « Desert Related Death ». International Journal of Environmental Research and Public Health 18, n^o 21 (27 octobre 2021) : 11272. http://dx.doi.org/10.3390/ijerph182111272.

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Introduction: Desert death is defined as any death that occurs in the desert and could be attributed to a list of causes including environmental, animal related, undetermined, and other causes. Death in the desert seems to be obscure and little discussed in the field of forensic medicine, despite its importance, and there is only limited literature available on this broad topic. This narrative review aims to identify the most common causes of desert death and its medicolegal implications. Desert death causes: Environmental causes of death could be a result of temperature and lightening-related causes. Moreover, a variety of animals found in deserts are considered to be threatening and fatal, in addition to other and undetermined causes. Medicolegal implications of desert death: Likely to arise from the difficulties faced in finding the cause of death are the identification of the victim and the postmortem injuries that occur. Conclusion: Desert death is a broad topic with great medicolegal significance. More information and case reports need to be added in the literature. Guidelines for people about the danger of going to deserts in specific weather conditions should be implemented. Safety regulations must be taken into account at all times.

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Robin, Libby, Steve Morton et Mike Smith. « Writing a History of Scientific Endeavour in Australia’s Deserts ». Historical Records of Australian Science 25, n^o 2 (2014) : 143. http://dx.doi.org/10.1071/hr14011.

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This special issue of Historical Records of Australian Science explores some of the sciences that have contributed to our understanding of inland Australia, country variously known as desert, the arid zone, drylands and the outback. The sciences that have concentrated on deserts include ecology, geomorphology, hydrology, rangeland management, geography, surveying, meteorology and geology, plus many others. In recognition that desert science has surged ahead in the past few decades, we have invited contributors who describe various different desert initiatives. We use these case studies to open up the discussion about how Australians see their desert lands, how this has changed over time and how desert scientists from the rest of the world regard the distinctive desert country in Australia.

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Marushia, Robin G., Matthew L. Brooks et Jodie S. Holt. « Phenology, Growth, and Fecundity as Determinants of Distribution in Closely Related Nonnative Taxa ». Invasive Plant Science and Management 5, n^o 2 (juin 2012) : 217–29. http://dx.doi.org/10.1614/ipsm-d-11-00074.1.

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AbstractInvasive species researchers often ask: Why do some species invade certain habitats while others do not? Ecological theories predict that taxonomically related species may invade similar habitats, but some related species exhibit contrasting invasion patterns. Brassica nigra, Brassica tournefortii, and Hirschfeldia incana are dominant, closely related nonnative species that have overlapping, but dissimilar, distributions. Brassica tournefortii is rapidly spreading in warm deserts of the southwestern United States, whereas B. nigra and H. incana are primarily limited to semiarid and mesic regions. We compared traits of B. tournefortii that might confer invasiveness in deserts with those of related species that have not invaded desert ecosystems. Brassica tournefortii, B. nigra and H. incana were compared in controlled experiments conducted outdoors in a mesic site (Riverside, CA) and a desert site (Blue Diamond, NV), and in greenhouses, over 3 yr. Desert and mesic B. tournefortii populations were also compared to determine whether locally adapted ecotypes contribute to desert invasion. Experimental variables included common garden sites and soil water availability. Response variables included emergence, growth, phenology, and reproduction. There was no evidence for B. tournefortii ecotypes, but B. tournefortii had a more rapid phenology than B. nigra or H. incana. Brassica tournefortii was less affected by site and water availability than B. nigra and H. incana, but was smaller and less fecund regardless of experimental conditions. Rapid phenology allows B. tournefortii to reproduce consistently under variable, stressful conditions such as those found in Southwestern deserts. Although more successful in milder, mesic ecosystems, B. nigra and H. incana may be limited by their ability to reproduce under desert conditions. Rapid phenology and drought response partition invasion patterns of nonnative mustards along a gradient of aridity in the southwestern United States, and may serve as a predictive trait for other potential invaders of arid and highly variable ecosystems.

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Pate, Russell R., Marsha Dowda, Ruth P. Saunders, Natalie Colabianchi, Morgan N. Clennin, Kerry L. Cordan, Geena Militello, Agnes Bucko, Dwayne E. Porter et Wm Lynn Shirley. « Operationalizing and Testing the Concept of a Physical Activity Desert ». Journal of Physical Activity and Health 18, n^o 5 (1 mai 2021) : 533–40. http://dx.doi.org/10.1123/jpah.2020-0382.

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Background: The prevalence of childhood obesity is higher in economically and socially deprived areas. Higher levels of physical activity reduce the risk of excessive weight gain in youth, and research has focused on environmental factors associated with children’s physical activity, though the term “physical activity desert” has not come into wide use. Methods: This exploratory study operationalized the term “physical activity desert” and tested the hypothesis that children living in physical activity deserts would be less physically active than children who do not. A cross-sectional study design was applied with 992 fifth-grade students who had provided objectively measured physical activity data. Five of 12 possible elements of the built environment were selected as descriptors of physical activity deserts, including no commercial facilities, no parks, low play spaces, no cohesion, and the presence of incivilities. Results: Univariate and multivariate analyses showed that only the absence of parks was associated with less physical activity in children. Conclusion: Children living in a “no park” zone were less active than their counterparts who lived near a park. This study contributes preliminary conceptual and operational definitions of “physical activity desert.” Future studies of physical activity deserts should be undertaken in larger and more diverse samples.

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Hamidi, Shima. « Urban sprawl and the emergence of food deserts in the USA ». Urban Studies 57, n^o 8 (12 juin 2019) : 1660–75. http://dx.doi.org/10.1177/0042098019841540.

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Providing access to a variety of healthy and affordable foods has been the goal of several federal and state policy initiatives in the USA. The first step towards the successful implementation of these initiatives is to identify food deserts and to understand the mechanism by which food deserts arise. This national-level study investigates the association between urban sprawl and the emergence of food deserts at both regional and neighbourhood levels. Multilevel analysis is used to model the likelihood of a census tract being a food desert, controlling for sociodemographic and built environmental characteristics. We find that urban sprawl, measured via a compactness index, holds a significant association with the likelihood of a census tract being a food desert. Specifically, a one unit increase in the compactness index is associated with a 5.6% decrease in the odds of a census tract being a food desert. In conclusion, we recommend increasing the land use density, mix and walkability of neighbourhoods to create a supportive and attractive environment for food retailers in which to invest.

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Murgante, Beniamino, Mohammad Eskandari Sani, Sara Pishgahi, Moslem Zarghamfard et Fatemeh Kahaki. « Factors Affecting the Lut Desert Tourism in Iran : Developing an Interpretive-Structural Model ». Sustainability 13, n^o 13 (29 juin 2021) : 7245. http://dx.doi.org/10.3390/su13137245.

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The Lut desert is one of the largest and most attractive deserts in Iran. The value of desert tourism remains unclear for Iran’s economy and has only recently been taken into consideration by the authorities, although its true national and international value remains unclear. This study was aimed at investigating the factors that influence tourism development in the Lut desert. Data collected through the purposive sampling method was analyzed using Interpretive Structural Modeling and the MICMAC Analysis. According to the results, cost-effective travel expenses, security, and safety provided in the desert, together with appropriate media advertising and illustration of the Lut desert (branding) are the leading factors that influence tourism in the Lut desert in Iran. This paper highlighted the importance of desert tourism, especially in this region.

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Lowe, Linnea, Cole Brokamp, Erika Rasnick, Eric S. Hall et Shauna Acquavita. « A Geographic Perspective on Opioid Misuse : Substance Abuse Treatment Deserts in Southwestern Ohio ». Ohio Journal of Public Health 4, n^o 1 (21 juin 2021) : 31–37. http://dx.doi.org/10.18061/ojph.v4i1.8075.

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Background: The opioid crisis is one of the most pressing public health issues facing Ohio, with an impact uneven-ly distributed across the state. This work examined geographical barriers to substance abuse treatment in southwestern Ohio through examining geographical areas with limited access to substance abuse treatment services and identifying substance abuse treatment deserts. Methods: The study domain included the 13 counties in the Ohio Mental Health and Addiction Service's Cincinnati region. Publicly available substance use disorders treatment data were collected from government agency resources, pharmaceutical websites, and web searches. Substance abuse treatment deserts were defined as areas in the 13-county study area that were not within a 15-minute drive from a treatment center. Results: We found large portions of the study region that were considered a substance abuse treatment desert for methadone and naltrexone/buprenorphine clinics, behavioral health treatment centers, and both medicated assisted treatment (MAT) and behavioral health treatment combined. Out of the 2 017 337 total persons living in the 13-county study area, 17% (n = 342 872) live in a desert for all MAT and behavioral treatment. Similarly, 19.7% (n = 396 581) live in a desert for naltrexone/buprenorphine treatment, 60.9% (n = 1 227 560) live in a desert for methadone treatment, and 19.7% (n = 396 581) live in a desert for behavioral health treatment. Conclusion: We successfully defined substance abuse treatment deserts in southwestern Ohio, which will be useful for future research to determine its association with opioid-related health outcomes. This resource is publicly available online (https://doi.org/10.5281/zenodo.4011051).

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Ding, Zhongli, Jimin Sun, Nat W. Rutter, Dean Rokosh et Tungsheng Liu. « Changes in Sand Content of Loess Deposits along a North–South Transect of the Chinese Loess Plateau and the Implications for Desert Variations ». Quaternary Research 52, n^o 1 (juillet 1999) : 56–62. http://dx.doi.org/10.1006/qres.1999.2045.

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Geological records have shown that the deserts east of the Helan Mountains in northern China were covered by grass during the Holocene Optimum, whereas during marine oxygen isotope stages 2 and 4 distribution of the deserts was almost the same as at present. The wide advance–retreat cycles of the deserts may have exerted an important control on grain-size changes in the loess of the Loess Plateau by altering the distance between the source and the accumulation zone of the loess. This challenges the widely accepted model that winter monsoon winds were the sole factor responsible for spatial and temporal changes in loess texture. To observe spatial changes in sedimentological characteristics of loess during the last glacial–interglacial cycle, the texture of loess was measured along a north–south transect of the Loess Plateau. This transect consists of nine loess sections, starting at Yulin in the transitional region between the Loess Plateau and the Mu Us Desert and ending at Weinan in the southernmost part of the Loess Plateau. Southward changes in sand (>63 μm) content along the transect suggest that variations in desert extent have indeed played a significant role in loess grain-size distributions, particularly in the northern part of the Loess Plateau. It is proposed that sand content (>63 μm%) of loess in the loess–desert transitional zone may be used as a proxy indicator for proximity to the desert margin.

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Chatterjee, Manas. « Desert dermatoses (Thar desert, India) ». Indian Journal of Dermatology 62, n^o 1 (2017) : 52. http://dx.doi.org/10.4103/0019-5154.198049.

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Zhang, Xin, Panpan Liu, Baolin Pan, Mingjian Wei et Zhuoyong Zhang. « Tracing the dune activation of Badain Jaran Desert and Tengger Desert by using near infrared spectroscopy and chemometrics ». Journal of Near Infrared Spectroscopy 27, n^o 5 (18 août 2019) : 370–78. http://dx.doi.org/10.1177/0967033519870303.

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Tracing the sand source is helpful to interpret the evolution of deserts and explain the relations between the desert and the climatic geographical condition around. Furthermore, it is helpful to investigate the reasons for sandstorms in corresponding areas. In this work, near infrared spectroscopy combined with hierarchical cluster analysis was proposed as a novel method to characterize sand samples collected from Badain Jaran and Tengger Deserts, two main sources of sandstorms in North China. Partial least square discriminant analysis gives a classification result with an accuracy of 100% for the estimation of hierarchical cluster analysis. The results provide support that Badain Jaran Desert and Tengger Desert have sand exchanged by monsoonal weather events. The transmission between the two deserts is also affected by the local terrain. The sand samples were also analyzed by electron microscopy, energy dispersive spectroscopy and Fourier transform infrared spectroscopy to investigate the sample differences in morphology, elemental contents and molecular structures. Near infrared spectroscopy combined with chemometric methods has the potential to be used for the identification of sand samples to determine the sources of sands with advantages of fast, nondestructive, low cost and in situ analysis.

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Li, Sheng Yu, Jia Qiang Lei, Xin Wen Xu, Hai Feng Wang et Feng Gu. « Dust Source of Sandstorm in the Tarim Basin, Northwest China ». Advanced Materials Research 518-523 (mai 2012) : 4592–98. http://dx.doi.org/10.4028/www.scientific.net/amr.518-523.4592.

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Dust supply is important to sandstorm occurrence as well as wind regime. Dust supply is closely related to groundsurface conditions showed by these index soil physical composition, soil moisture, vegetation cover, human activities. The physical conditions of groundsurface in the Tarim basin is distributed in a ringlike pattern. From edge to hinterland, there are various landscapes in turn as follow: mountains, piedmont pluvial and alluvial fans and plains and shifting desert. At the same time, in this turn, different types of soil has been developed there: brown desert soil, ancient oasis cultivated soil (anthropogenic-alluvial soil), swamp soil, desert forest meadow soil, paddy soil, saline soil, takyr soil, shifting sandy soil, and so on. Through comprehensive analysis, some conclusions were drew as the follow: (1)shifting deserts are the major dust source of sandstorm occurred in the hinterland and the south fringe of the Taklimakan Desert; (2)cultivated soils are another dust source of sandstorm occurred in oasis areas disturbed by high-intensity human activities; (3) gobi deserts in upper of piedmont pluvial and alluvial fans and desert forest areas on alluvial plains are the potential dust sources with high dust-emitting ability that can be activiated by human activities.

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Smets, Vincent, Jeroen Cant et Stefanie Vandevijvere. « The Changing Landscape of Food Deserts and Swamps over More than a Decade in Flanders, Belgium ». International Journal of Environmental Research and Public Health 19, n^o 21 (25 octobre 2022) : 13854. http://dx.doi.org/10.3390/ijerph192113854.

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Food deserts and swamps have previously been mostly studied in Anglo-Saxon countries such as the USA and Great Britain. This research is one of the first studies to map food deserts and swamps in a mainland European, densely populated but heavily fragmented region such as Flanders. The evolution of food deserts and swamps between 2008 and 2020 was assessed. Special focus was given to areas where high numbers of elderly, young people and/or families with low income live. Food deserts were calculated based on supermarket access within 1000 m and bus stop availability, while food swamps were calculated using the Modified Food Environment Retail Index. The main cause behind the formation of food deserts in Flanders is its rapidly aging population. Food deserts with a higher number of older people increased from 2.5% to 3.1% of the residential area between 2008 and 2020, housing 2.2% and 2.8% of the population, respectively. Although the area that could become a food desert in the future due to these sociospatial and demographic evolutions is large, food deserts are currently a relatively small problem in Flanders in comparison to the widespread existence of food swamps. Unhealthy retailers outnumbered healthy retailers in 74% of residential areas in 2020, housing 88.2% of the population. These food swamps create an environment where unhealthy food choices predominate. Residential areas with a higher number of elderly people, young people and families with low incomes had healthier food environments than Flanders as a whole, because these areas are mostly found in dense urban centers where the ratio of healthy food retailers to all retailers is higher. This research showed that food deserts and swamps could be a growing problem in European regions with a high population density that experience the high pressures of competing land uses.

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Sosa, Victoria, Israel Loera, Diego F. Angulo, Marilyn Vásquez-Cruz et Etelvina Gándara. « Climate change and conservation in a warm North American desert : effect in shrubby plants ». PeerJ 7 (7 mars 2019) : e6572. http://dx.doi.org/10.7717/peerj.6572.

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Background Deserts are biologically rich habitats with a vast array of animals and plants adapted to xeric conditions, and most deserts are among the planet’s last remaining areas of total wilderness. Among North American deserts, the Chihuahuan Desert has the highest levels of diversity and endemism. To understand the effect of future climate change on plants distributed in this arid land and propose effective conservation planning, we focused on five endemic shrubby species that characterize the Chihuahuan Desert and used an integrative approach. Methods Ecological niche-based modeling, spatial genetics and ecological resistance analyses were carried out to identify the effect of global warming on the studied five shrubby species. Key areas that need to be preserved were identified taking into account the existing protected areas within the Chihuahuan Desert. Results The extent of future distribution will vary among these species, and on average expansion will occur in the western part of the Chihuahuan Desert. For most species low environmental resistance to gene flow was predicted, while higher future resistance was predicted for one species that would lead to increased population isolation. The highest haplotype diversity was identified in three hotspots. Based on future suitability of habitat and in the haplotype diversity we suggest preserving two hotspots of genetic diversity in the Sierra Madre Oriental, located in areas without protection. The third hotspot was detected in the well preserved Tehuacán-Cuicatlán Man and Biosphere Reserve. Conclusion Global climate change will have an effect in arid adapted plants, favoring expansion in the western of the Chihuahuan Desert however negatively affecting others with high ecological resistance disrupting gene flow. Two hotspots of genetic diversity in the Sierra Madre Oriental should be protected.

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Francis, Lucine, Nancy Perrin, Frank C. Curriero, Maureen M. Black et Jerilyn K. Allen. « Food Desert Status of Family Child Care Homes : Relationship to Young Children’s Food Quality ». International Journal of Environmental Research and Public Health 19, n^o 11 (24 mai 2022) : 6393. http://dx.doi.org/10.3390/ijerph19116393.

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Family child care homes (FCCHs) are a favored child care choice for parents of young children in the U.S. Most FCCH providers purchase and prepare foods for the children in their care. Although FCCH providers can receive monetary support from the Child and Adult Care Food Program (CACFP), a federal subsidy program, to purchase nutritious foods, little is known about FCCH providers’ access to nutritious foods, especially among FCCH providers serving children from communities that have been historically disinvested and predominantly Black. This study aims to describe the food desert status of FCCHs in Baltimore City, Maryland, and examine the relationship between food desert status and the quality of foods and beverages purchased and provided to children. A proportionate stratified random sample of 91 FCCH providers by CACFP participation status consented. Geographic information system mapping (GIS) was used to determine the food desert status of each participating FCCH. Participants reported on their access to food and beverages through telephone-based surveys. Nearly three-quarters (66/91) of FCCHs were located in a food desert. FCCH providers working and living in a food desert had lower mean sum scores M (SD) for the quality of beverages provided than FCCH providers outside a food desert (2.53 ± 0.81 vs. 2.92 ± 0.70, p = 0.036, respectively). Although the significant difference in scores for beverages provided is small, FCCH providers working in food deserts may need support in providing healthy beverages to the children in their care. More research is needed to understand food purchases among FCCH providers working in neighborhoods situated in food deserts.

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Harris, Grant M., David R. Stewart, David Brown, Lacrecia Johnson, Jim Sanderson, Aaron Alvidrez, Tom Waddell et Ron Thompson. « Year-round water management for desert bighorn sheep corresponds with visits by predators not bighorn sheep ». PLOS ONE 15, n^o 11 (24 novembre 2020) : e0241131. http://dx.doi.org/10.1371/journal.pone.0241131.

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Managing water (e.g., catchments) to increase the abundance and distribution of game is popular in arid regions, especially throughout the southwest United States, where biologists often manage water year-round for desert bighorn sheep (Ovis canadensis nelsoni). Bighorn may visit water when predators (e.g., mountain lions [Puma concolor], coyotes [Canis latrans]) do not, suggesting that differences in species ecology or their surface water requirements influence visit timing. Alternatively, visits by desert bighorn sheep and predators may align. The former outcome identifies opportunities to improve water management by providing water when desert bighorn sheep visit most, which hypothetically may reduce predator presence, range expansion and predation, thereby supporting objectives to increase sheep abundances. Since advancing water management hinges on understanding the patterns of species visits, we identified when these three species and mule deer (Odocoileus hemionus) visited managed waters in three North American deserts (Chihuahuan, Sonoran, Mojave). We unraveled the ecological basis describing why visits occurred by associating species visits with four weather variables using multi-site, multi-species models within a Bayesian hierarchical framework (3.4 million images; 105 locations; 7/2009-12/2016). Desert bighorn sheep concentrated visits to water within 4–5 contiguous months. Mountain lions visited water essentially year-round within all deserts. Higher maximum temperature influenced visits to water, especially for desert bighorn sheep. Less long-term precipitation (prior 6-week total) raised visits for all species, and influenced mountain lion visits 3–20 times more than mule deer and 3–37 times more than sheep visits. Visits to water by prey were inconsistent predictors of visits to water by mountain lions. Our results suggest improvements to water management by aligning water provision with the patterns and ecological explanations of desert bighorn sheep visits. We exemplify a scientific approach to water management for enhancing stewardship of desert mammals, be it the southwest United States or arid regions elsewhere.

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Port, U., et M. Claussen. « Transitivity of the climate–vegetation system in a warm climate ». Climate of the Past 11, n^o 11 (25 novembre 2015) : 1563–74. http://dx.doi.org/10.5194/cp-11-1563-2015.

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Abstract. To date, the transitivity of the global system has been analysed for late Quaternary (glacial, interglacial, and present-day) climate. Here, we extend this analysis to a warm, almost ice-free climate with a different configuration of continents. We use the Earth system model of the Max Planck Institute for Meteorology to analyse the stability of the climate system under early Eocene and pre-industrial conditions. We initialize the simulations by prescribing either dense forests or bare deserts on all continents. Starting with desert continents, an extended desert remains in central Asia in the early Eocene climate. Starting with dense forest coverage, the Asian desert is much smaller, while coastal deserts develop in the Americas which appear to be larger than in the simulations with initially bare continents. These differences can be attributed to differences in the large-scale tropical circulation. With initially forested continents, a stronger dipole in the 200 hPa velocity potential develops than in the simulation with initially bare continents. This difference prevails when vegetation is allowed to adjust to and interact with climate. Further simulations with initial surface conditions that differ in the region of the Asian desert only indicate that local feedback processes are less important in the development of multiple states. In the interglacial, pre-industrial climate, multiple states develop only in the Sahel region. There, local climate–vegetation interaction seems to dominate.

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Abbas, Naveed, Muhammad Zafar, Mushtaq Ahmad, Ashwaq T. Althobaiti, Mohamed Fawzy Ramadan, Trobjon Makhkamov, Yusufjon Gafforov et al. « Tendril Anatomy : A Tool for Correct Identification among Cucurbitaceous Taxa ». Plants 11, n^o 23 (28 novembre 2022) : 3273. http://dx.doi.org/10.3390/plants11233273.

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This research examined the histological micro-structure of tendril vasculature in cucurbitaceous taxa. In this research, the tendril anatomy of 17 taxa of Cucurbitaceae categorized into seven genera, including Cucumis (five species), Cucurbita and Luffa (three species each), Citrullus and Momordica (two species each) while Lagenaria and Praecitrullus (one species each), collected from different areas of the Thal desert were examined via microscopic imaging to explore its taxonomic significance. Tendril transverse sections were cut with a Shandon Microtome to prepare slides. The distinctive characteristics of taxonomic value (qualitative and quantitative) include tendril and vascular bundle shape, variation in the number of vascular bundles, tendril diameter length, layers of sclerenchyma, and shape of collenchyma and epidermal cells. Tendril shapes observed are irregular, slightly oval-shaped, slightly C shaped, angular (4-angled, 6-angled, or polygonal), and star shaped. Quantitative measurements were taken to analyze the data statistically using SPSS software. Cucurbita pepo had a maximum tendril diameter length of 656.1 µm and a minimum in Momordica balsamina of 123.05 µm. The highest number of vascular bundles (12) were noticed in Luffa acutangula var.amara. Angular type was prominent in collenchyma, and irregular shape was dominant in sclerenchyma cells. A maximum of seven to nine sclerenchyma layers were present in Lagenaria siceraria and a minimum of two or three layers in Cucumis melo subsp. agrestis, Cucumis melo var. flexuosus, and Cucumis melo var.cantalupensis. Epidermis cells also show great variations with a rectangular shape being dominant. Statistical UPGMA dendrogram clustering of tendril vasculature traits shows that histological sections studied with microscopic techniques can be used to identify species and will play a vital role in future taxonomic and phylogenic linkages.

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Donovan, Brienne, Jeffrey Anderson, Chinaemelum Akpunonu, Lisa Rae et Huaqing Zhao. « 522 Food Deserts and Burn Wound Healing - Does Geography in an Urban Environment Matter ? » Journal of Burn Care & ; Research 43, Supplement_1 (23 mars 2022) : S96—S97. http://dx.doi.org/10.1093/jbcr/irac012.153.

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Abstract Introduction Many burn injury victims in the United States live in regions designated as food deserts. The United States Department of Agriculture (USDA) defines food deserts as low-income areas where a substantial number of residents do not have access to a supermarket. Nutrition is known to be critical to wound healing. The purpose of this investigation was to determine if there is a relationship between residence in a USDA designated food desert, burn patient cormorbidities, and wound healing at an urban academic medical center. Methods We performed a retrospective review of burn injured patients at an ABA verified urban academic burn center between September 2018 and April 2021. Inclusion criteria were burn injury of less than 20% total body surface area (TBSA), age ≥ 18, and single operation for split thickness skin grafting. Zip codes were used in conjunction with the USDA Food Access Research Atlas to classify residence in food deserts. The primary outcome was donor site time to healing. A multivariable logistical regression analysis was performed to evaluate risk factors for poor wound healing at an urban academic burn center and to determine if residence in a USDA delegated food desert was one of those risk factors. Results A total of 150 patients were identified for inclusion from September 2018 through April 2021. There were 73 women (48.7%) and 77 men (51.3%). The median age was 48.5 (IQR 34.0, 58.0). The average body mass index (BMI) was 28.2 (6.6). Age (p=0.60), sex (p=0.35), hypertension (p=0.74), chronic obstructive pulmonary disease (p=0.076), hyperlipidemia (p=0.77), congestive heart failure (p=0.47), and BMI (p=0.37), and time to donor site healing (p=0.55) were not significantly different between patients who lived in food deserts and those who did not. Patients who lived in food deserts, however, had a higher incidence of diabetes (p=0.05). The multivariable model also shows that time to healing is not different between patients who live in food deserts and those who did not. However, the multivariable model shows that patients with diabetes have an increased time to healing (p=0.002). Conclusions Residence in a USDA delegated food desert does not significantly influence time to healing of donor sites in burn injured patients. However, diabetes is significantly higher in patients who live in USDA delegated food deserts, and diabetes demonstrates a significant delay in wound healing. This is the first study comparing residence in a USDA food desert, burn patient comorbidities, and time to wound healing in an urban burn population.

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Cloudsley-Thompson, John L. « The Adaptational Diversity of Desert Biota ». Environmental Conservation 20, n^o 3 (1993) : 227–31. http://dx.doi.org/10.1017/s0376892900023018.

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The climatic similarity of desert environments everywhere has engendered parallelism and the evolution of ecological analogues in different regions of the world. This tends to mask the actual diversity of their inhabitants. Although biodiversity may be poor in the desert, at least compared with most other terrestrial ecobiomes, deserts are extremely vulnerable to degradation and therefore deserve as much as, or even more, consideration than many biologically richer habitats.

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Bollasina, Massimo, et Sumant Nigam. « Modeling of Regional Hydroclimate Change over the Indian Subcontinent : Impact of the Expanding Thar Desert ». Journal of Climate 24, n^o 12 (15 juin 2011) : 3089–106. http://dx.doi.org/10.1175/2010jcli3851.1.

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Abstract The Thar Desert between northwestern India and Pakistan is the most densely populated desert region in the world, and the vast surrounding areas are affected by rapid soil degradation and vegetation loss. The impact of an expanded desert (implemented by changing vegetation type and related greenness fraction, albedo, surface roughness length, emissivity, among others) on the South Asian summer monsoon hydroclimate is investigated by means of 7-month, 4-member ensemble sensitivity experiments with the Weather Research and Forecasting model. It is found that extended desertification significantly affects the monsoon at local and large scales. Locally, the atmospheric water cycle weakens because precipitation, evaporation, and atmospheric moisture convergence all decrease; soil moisture and runoff reduce too. Air temperature cools because of an increase in albedo (the desert makes the area brighter) and a reduction of surface turbulent fluxes; the cooling is partially offset by adiabatic descent, generated to maintain thermodynamic balance and originating at the northern flank of the low-level anticyclone forced by desert subsidence. Regionally, an anomalous northwesterly flow over the Indo-Gangetic Plain weakens the monsoon circulation over northeastern India, causing precipitation to decrease and the formation of an anomalous anticyclone in the region. As a result, the middle troposphere cools because of a decrease in latent heat release, but the ground heats up because of a reduction in cloudiness. At larger scale, the interaction between the anomalous circulation and the mountains leads to an increase in precipitation over the eastern Himalayas and Indochina. The findings of this study reveal that the expansion of the Thar Desert can lead to a pronounced and large-scale impact on summer monsoon hydroclimate, with a potential to redistribute precious water over South Asia.

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Liu, Xiaoyu, et Liangjie Xin. « China’s deserts greening and response to climate variability and human activities ». PLOS ONE 16, n^o 8 (30 août 2021) : e0256462. http://dx.doi.org/10.1371/journal.pone.0256462.

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Vegetation, which is a good indicator of the impacts of climate variability and human activities, can reflect desert ecosystem dynamics. To reveal the vegetation variations in China’s deserts, trends in the monthly, seasonal, and annual normalized difference vegetation index (NDVI) from 2000 to 2017 were measured both temporally and spatially by the Theil-Sen estimator and Mann-Kendall test. Additionally, correlation coefficients and residual analysis were employed to evaluate the correlations between the NDVI and climatic factors and to distinguish the impacts of climate variability and human activities. The results showed that China’s deserts underwent greening. The annual NDVI showed a significant increasing trend at a rate of 0.0018/yr, with values of 0.094 in 2000 and 0.126 in 2017. Significant increasing trends in NDVI were observed in all four seasons. The NDVI were higher in summer and autumn than in spring and winter. Both the monthly NDVI and its trends showed an inverted U-shaped curve during the year. Spatially, the greening trends were mainly distributed on the southern edge of the Gurbantunggut Desert, in the northwestern part of the Taklimakan Desert, and in the Kubuqi Desert. The correlations between the NDVI and climatic factors at the monthly and seasonal scales were stronger than those at the annual scale. Temperature and precipitation had positive effects on NDVI at the monthly and seasonal scales, but only precipitation had a positive effect at the annual scale. Human activities, especially oasis expansion and sand stabilization measures, were two major causes of large increasing areas of desert greening in China indicated by the NDVI.

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Campbell, Colin, Mónica María Calderón Pinedo, Willa Midgette et Justin Vieira. « The Consequences of Living in a Small-town Food Desert : Mixed Methods Evidence from a Quasi-Experiment ». Social Currents 7, n^o 6 (11 juin 2020) : 563–81. http://dx.doi.org/10.1177/2329496520928428.

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Past research finds that living in a food desert is associated with an unhealthy diet and poor health; however, more recent studies of urban food deserts suggest that these findings may be spurious. In this article, we leverage the flooding and subsequent closing of the only grocery store in a small town to examine the effects of living in a small-town food desert. Using difference-in-difference methods, we find that opening a grocery store in a small-town food desert is not associated with changes in diet, but we find that opening a grocery store in a food desert is associated with improved food access. Findings from in-depth interviews shed further light on how residents of a small-town food desert decide where to shop and how routine activities provide access to a range of nonlocal grocery stores. Moreover, we find that the absence of a grocery store negatively affects social relationships. While the findings add to growing skepticism about food desert effects on diet, the findings reveal important food desert effects on food access and also the social consequences of living in a food desert.

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Cooksey Stowers, Kristen, Qianxia Jiang, Abiodun Atoloye, Sean Lucan et Kim Gans. « Racial Differences in Perceived Food Swamp and Food Desert Exposure and Disparities in Self-Reported Dietary Habits ». International Journal of Environmental Research and Public Health 17, n^o 19 (29 septembre 2020) : 7143. http://dx.doi.org/10.3390/ijerph17197143.

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Both food swamps and food deserts have been associated with racial, ethnic, and socioeconomic disparities in obesity rates. Little is known about how the distribution of food deserts and food swamps relate to disparities in self-reported dietary habits, and health status, particularly for historically marginalized groups. In a national U.S. sample of 4305 online survey participants (age 18+), multinomial logistic regression analyses were used to assess by race and ethnicity the likelihood of living in a food swamp or food desert area. Predicted probabilities of self-reported dietary habits, health status, and weight status were calculated using the fitted values from ordinal or multinomial logistic regression models adjusted for relevant covariates. Results showed that non-Hispanic, Black participants (N = 954) were most likely to report living in a food swamp. In the full and White subsamples (N = 2912), the perception of residing in a food swamp/desert was associated with less-healthful self-reported dietary habits overall. For non-Hispanic Blacks, regression results also showed that residents of perceived food swamp areas (OR = 0.66, p < 0.01, 95% CI (0.51, 0.86)) had a lower diet quality than those not living in a food swamp/food desert area. Black communities in particular may be at risk for environment-linked diet-related health inequities. These findings suggest that an individual’s perceptions of food swamp and food desert exposure may be related to diet habits among adults.

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Papelitzky, Elke. « Sand, Water, and Stars : Chinese Mapping of the Gobi and Taklamakan Deserts ». T’oung Pao 107, n^o 3-4 (8 septembre 2021) : 376–416. http://dx.doi.org/10.1163/15685322-10703004.

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Abstract Many Chinese maps from the mid-sixteenth century onwards mark the Gobi Desert as a prominent strip visually separating China from what lies beyond. Even before that time, the Gobi, as well as the Taklamakan Desert appeared on maps. Influenced by statements from the early classic “Yugong,” Chinese scholars and Han literati during late imperial China’s history had perceived the deserts as some kind of boundary, while with the integration of these regions into Qing territory, the imperial Manchu view shifted away from the desert being a boundary. The terms for the desert as well as the graphical depiction on maps link the desert to water and to some extent also to celestial phenomena. This article explores the history and cultural significance of the desert from the Song to the mid-Qing period based on maps in relation with relevant texts and draws connections to the origins and changes of these depictions.

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