The Gobi Desert Can Be Found on Which Continent?
Book 2
Michael Heiner , ... Joseph Kiesecker , in Encyclopedia of the Globe's Biomes, 2020
Introduction
The Gobi Desert basin lies across southern Mongolia and northwestern People's republic of china between the Mongolian Altai and Khangai mountains and the Himalayan Plateau (see map in Fig. 1). This region is a common cold desert with a continental climate and long, cold winters. Average temperatures range from below − 20°C in January to over 33°C in July (Hijmans et al., 2005). In the rain shadow of the Himalayas, precipitation ranges from less than 40 mm in extreme arid areas to over 200 mm in the Gobi-Altai mountains (Hijmans et al., 2005), and varies greatly interannually, with some areas not receiving any measurable precipitation for years at a time (Vandandorj et al., 2015).
Fig. 1. Gobi Desert region every bit delineated by WWF (Olson et al. 2001) and Nuance (2007). Basemap: ESRI (2019).
The name "Gobi" comes from the Mongolia word "Govi" for a dry landscape with characteristic barren vegetation including palatable forage species (Allium and Nitraria spp.) and rare medicinal plants. Gobi desert vegetation is a mix of true desert, desert grasslands, and steppe. Despite the climate, the Mongolian portion of the Gobi Desert region supports globally-meaning wild lands and wildlife, and is office of the largest steppe ecosystem in the earth that supports its historic wild fauna aggregation, including long distance wild fauna migrations (Batsaikhan et al., 2014). Historically, this region was near the centre of the Mongol Empire (c. 1206–1294) and has been crossed by man migrations and trade routes for 5000 years (Hare, 2009).
Arid lands, which include the semi-arid grasslands and deserts of the Gobi Desert region, cover a third of the world'south land mass (Mortimore et al., 2009) and support unique biodiversity and many endangered species (Durant et al., 2012; IUCN, 2011). However, as much as 20% has experienced degradation (Reynolds et al., 2007; Safriel, 2006; UNCCD, 1994) and less than 10% of arid lands benefit from some form of protection (Hoekstra et al., 2005). Arid and semi-arid biomes are habitation to 20% of the earth's population, mostly subsistence farmers and pastoralists (Mortimore et al., 2009). The dry climate promotes the formation and concentration of important minerals and salts through the motion and evaporation of h2o. Half of the world'south copper and uranium and 75% of world oil reserves are in arid lands (UNEP, 2006).
Parts of the Mongolian Gobi Desert region accept been identified equally amidst the world'southward largest and most intact (to the lowest degree converted) remaining wild areas (Allan et al., 2017; Kennedy et al., 2019), and the human population density was very depression historically and still is today (ECJRC and CIESIN, 2015). The Mongolian Gobi Desert currently supports more than xxx mammals, herptiles, and birds listed equally nationally threatened or endangered (Clark et al., 2006; Terbish et al., 2006; Gombobataar et al., 2011), including the globe's largest remaining populations of Asiatic wild ass or khulan (Equus hemionus), wild Bactrian camel (Camelus ferus), Gobi brown bear (Ursus arctos gobiensis), Siberian ibex (Capra sibirica), Goitered gazelle (Gazella subgutturosa), and Mongolian gazelle (Procapra gutturosa), (Kaczensky et al., 2015; Mallon, 2008a,b). The low mountain ranges as well support 1 of the most stable and productive populations of Snow Leopards (Panthera uncia) in the global range (Sharma et al., 2014; Jackson et al., 2009).
The Mongolia steppes and desert grasslands also support traditional nomadic pastoralism that originated thousands of years agone. Mongolia nomadic pastoralists spend the wintertime at fixed households and shelters, and spend spring, summer, and autumn traveling between seasonal camps and pastures, though grazing practices and herd composition vary by geography and climate. In less productive desert grasslands, pastoralists typically visit as many equally 10–fifteen seasonal pastures over the form of a yr. In Mongolia, domestic livestock include horses, camels, yak, and cattle, though sheep and goats are the most numerous. Extreme winter weather condition events, sometimes coupled with summer drought, can cause catastrophic die-offs of livestock and wild animals. These weather events occur oftentimes enough to earn the proper name "dzud." Dzud events take a variety of forms, including "white dzud"—deep snow reducing admission to pasture forage, "black dzud"—extreme cold and no snow reducing forage and water availability, "storm dzud"—loftier winds and heavy snow, "iron dzud"—bulletproof ice covering pasture forage, "combined dzud"—deep snow and extreme cold, and "hoofed dzud"—out of season movements of many livestock to i pasture that eliminates forage with trampling and grazing (Begzsuren et al., 2004; Fernandez-Gimenez et al., 2011).
Though the Mongolian Gobi Steppe system still supports its historic wildlife and pastoral traditions, the wildlife and pastoral livelihoods face increasing threats and pressures following the transition from a soviet to market economic system in 1990. Pastoral systems and grazing practices have inverse in response (Fernandez-Gimenez and Batbuyan, 2004; Fernandez-Gimenez, 2001), and the number of livestock has nearly tripled, growing from 25 to over 66 million animals, in fewer, larger herds (National Statistical Part of Mongolia, 2018). This has resulted in overgrazing, especially in areas virtually rural population centers and h2o sources (Stumpp et al., 2005), though estimates of the degree and extent of rangeland deposition vary (Jamsranjav et al., 2018; Addison et al., 2012). These rapid changes have led to concerns well-nigh ecological tipping points, the loss of knowledge of traditional herding practices, and the loss of cultural identity (Fernandez-Gimenez et al., 2017).
A possibly more than urgent threat to wild fauna and biodiversity is the cumulative impacts of rapid growth of mining and related infrastructure (Suzuki, 2013; Batsaikhan et al., 2014). Mongolia is rich in mineral resources, and mineral exploration and extraction is increasing dramatically. In 2012, 14% of Mongolia's surface surface area and 24% of the Gobi study area was leased for mineral extraction or exploration (MMRE, 2012). Though the straight impacts of mining on land and water are significant and tin can attain far beyond the mine site, mayhap the nigh urgent threat to wild fauna is created by transportation infrastructure and traffic to support mining operations that create barriers to movement (Nandintsetseg et al., 2019; Batsaikhan et al., 2014; Ito et al., 2013).
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Volume iii
Frank Yonghong Li , ... Karsten Wesche , in Encyclopedia of the Globe'southward Biomes, 2020
Biodiversity Patterns
The temperate steppes edge with the Gobi deserts at the dry stop, and the temperate forests at the boiling terminate. The steppe plants, especially ascendant Stipa species, take xeric structural traits such every bit reduced leaf area, leaf involution, stomatal subsidence, and well-developed root system. Many plants (e.g., Stipa, Festuca and Allium) form dense clumps with shoot bases being thickly clothed by persistent dead foliage sheaths to avoid overheating of the footing in summer and to protect regenerative buds in winter (Li et al., 1980b).
Establish species richness and biomass production increases with the climatic humidity from desert steppes via typical steppes to meadow steppes (Li et al., 1994; Bai et al., 2009). The species density surveyed using nested quadrats increases from 8 species on one chiliad2, 12 species on 16 yard2 and xvi species on 256 m2 in desert steppe sites with atmospheric precipitation around 150 mm, via fourteen species on 1 yardii, 21 species on xvi thousandii and 29 species on 256 thou2 in typical steppe sites with precipitation around 350 mm, to xx species on 1 1000two, 32 species on 16 m2 and 42 species on 256 m2 at meadow steppe sites with precipitation effectually 500 mm (Fig. 5A ). The density recorded in these 1-mii quadrats is similar to that reported by Ma and Fang (2006) for the Inner Mongolian steppes, that is, ten (range 4–23), 12 (5–25) and 20 (10–35) species on 1 yard2 for desert steppes, typical steppes and meadow steppes, respectively based on a survey at 207 sites. The ecological turnover of steppe species of the same genera is very pronounced along the climate gradient, peculiarly for the genera Stipa (Fig. 5B), Astragalus and Caragana, and the same holds true for Kobresia species (Zhang et al., 1995).
Fig. 5. (A) Species density of desert steppes, typical steppes and meadow steppes recorded using nested quadrats of 0.125 to 256 m2. The values are the averages of 18, 18 and 13 nested quadrats respectively for the desert steppes, typical steppes and meadow steppes. (B) Substitution of Stipa species along the temperature-precipitation gradient (the ways and ranges of temperature and precipitation of their distribution sites surveyed) on the Mongolian Plateau.
Original Information of F.Y. Li.The species richness of alpine, semi-barren steppes is like to that of temperate, semi-arid steppes. Alpine meadows are more often than not more than various than steppes, having 45, 35 and 23 species in average for the communities dominated Kobresia pygmaea, K. humilis and K. tibetica (marshy), respectively, recorded in twenty quadrats of 0.five m2 in a survey at representative sites of these alpine meadows in the northeastern QT Plateau (Wang et al., 1999).
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ASIA, Fundamental AND NORTH, STEPPES, DESERTS, AND FORESTS
William Honeychurch , Joshua Wright , in Encyclopedia of Archaeology, 2008
The Domestication of Inner Asia
The Neolithic of Mongolia is dated from 8000 to 4500 BP and is all-time known from sites located in the Gobi desert and the eastern steppe where mixed microlithic assemblages and fragments of low fired, gray and ruddy coarse ware ceramics are found, often with corded and painted decorations. The term Neolithic in the case of Inner Asia is not always defined past the domestication of plants and animals as in most other regions of Eurasia, just instead by the advent of ceramic engineering science. The initial indication that hunter-gatherer groups began exploiting local environments in novel means is the advent of grinding stones at sites having typical Neolithic antiquity assemblages, such as Shabarak Us (Bayanzag Culture), in the South Gobi of Mongolia. Shabarak U.s.a. is located in an area of playas and stabilized sand dunes discipline to wind erosion that exposed 18 sub-sites having microlithic industries, ceramics, polished adzes, bifacial projectile points, and ostrich eggshell artifacts. The site is described in the Russian literature equally an early to center Neolithic temporary camp, probably inhabited past semi-mobile groups from 6000–5000 BP. Based on the evidence for grinding slabs and pestles, Shabarak Usa is thought to represent either incipient agriculture or a greater specialization in the use of wild grains. In either example, the appearance of such artifacts at a number of sites in the Gobi region suggests an important investment in a broader range of subsistence activities.
During the mid to tardily Neolithic of eastern Mongolia (5200–4500 BP), there is fabric testify suggesting simple agricultural production, sedentism, and exploitation of large herbivores such as wild cattle and equus caballus. The site that all-time characterizes Neolithic agricultural production is Tamsagbulag located in Dornod province on the eastern Mongolian steppe. Broad horizontal exposures at this site revealed a large number of rectangular pit-houses, the largest of which encompassed an area of 42 m2. Small pit burials with interred individuals positioned in crouching or sitting positions and covered with red ochre powder were discovered below the floor levels of these houses, along with blended tools and beat beads. The combined antiquity assemblage of both houses and burials provides a unique perspective on a small-scale steppe grouping employing simple agronomical techniques to grow millet and specialized hunting to obtain big grazing animals.
The antiquity inventory from Tamsagbulag consists of wedge-shaped prismatic cores and a wide diversity of blade-based implements, an advanced os industry, and ceramic vessels. Tools related to agriculture are numerous and include grinding stones and pestles, round quern stones, hoes, and weights for earthworks sticks. Indications of extensive and specialized employ of wild animals are based on the faunal remains recovered from habitation deposits, including evidence for fishing. In add-on to human interments beneath pit house floors, excavations also revealed pits containing large numbers of equus caballus and cattle bones, including several conspicuously large bullhorns. Other intentional deposits of cattle basic are known from the eastern Mongolian steppe and have been interpreted every bit cult practices to ensure agronomical success.
Tamsagbulag provides evidence that simple agronomics was practiced on the northeastern steppe, however, many contemporary areas take no such evidence. One example is Serovo period hunter-gatherer groups (6200–5000 BP) known from late Neolithic cemeteries such as Ust'-Ida, forth the shores of Lake Baikal and the Angara river of Siberia. These groups included a specialization in seals equally well as a number of ungulate species in their local hunting adaptation. Hunting and gathering subsistence practices likewise characterized the loftier Altai Mount and Gobi-Altai regions of western Inner Asia and seem to have been followed direct past simple herding economies. Southeast of Lake Baikal a blueprint more like to that of the Gobi Neolithic is present. Short-term campsites such as Budulan on the banks of the Onon river were inhabited during the fifth millennium BP by semi-mobile hunter-gatherers using a microlithic tool kit, thin-walled ceramics with rounded bases, grinding stones, rock pestles, and mortars. As in the case of Shabarak Us, archaeologists argue that the occurrence of grain processing rock assemblages at Budulan and other such sites may represent increasingly specialized gathering practices or experimentation with domesticates.
Recent archaeological evidence suggests that Neolithic groups of eastern Inner Mongolia experienced a substantially dissimilar subsistence trajectory from those regions described above. The traditional model for the rising of agriculture across Mainland china is ane of improvidence outward from the Xanthous River basin. This caption for agricultural origins has been challenged by radiocarbon dates from Inner Mongolia and northeastern Cathay where ii indigenous agronomical traditions emerged at very early periods, the Xinglongwa (8000–6800 BP) and Zhaobaogou (6800–6000 BP) cultures. These cultures relied upon hunting, simple tillage, and probably domesticated pigs. By the fifth millennium BP, when initial changes in food production are thought to have occurred on the northern steppe, Inner Mongolian groups of the Hongshan/Xiaoheyan (6500–4200 BP) cultures resided in permanent dispersed villages of i to 2 hectares having pit and surface dwellings along with numerous storage pits for grain. Due east Inner Mongolian subsistence at this time consisted of animal husbandry, especially of pigs, simple hoe-based agronomics, and deer hunting. Craft production included microlithic and polished stone industries as well equally bone, ceramic, and impressive jade object industry.
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Introduction
In Discovery of Oyu Tolgoi, 2019
Dedicated to our families
The discovery of the Oyu Tolgoi copper–gilded eolith, made almost 20 years ago in the Southern Gobi Desert, was a remarkable event in the history of modern Mongolia. As one of the well-nigh significant global copper–gold porphyry discovery in contempo years, this discovery marks a meaning milestone in the history of Mongolian mining industry and the copper manufacture worldwide.
The discovery of this eolith was the culmination of 2 years of exploration activity first performed by the Erdenet–Magma Joint Venture and subsequently by BHP geoscientists between 1995 and 1997.
It appears that the early on stages of this discovery were veiled in a shroud of mystery, which has led to much erroneous conjecture and speculation over the years. The authors of this volume, all of whom participated in the development and implementation of the exploration program, believe that the earliest stages of geological exploration are probably the nigh disquisitional and often the about challenging in the process of any mineral discovery. In this volume, they nowadays a step-past-footstep detailed account of the sequence of events that led them to this earth-grade discovery and share their thrilling experiences from the early on days of the deposit's discovery history.
A critically important aspect of any geological exploration program is to conduct acceptable research during the "desktop stage" of the program to be able to select, with a reasonable caste of confidence, the most geologically permissive exploration terrane. Research may include some preliminary field reconnaissance. Failure to locate a fertile terrane at an early on stage will generate discouraging field exploration results, which volition delay or prevent the realization of the final goal of success. Also, methods and approaches selected early on have a significant impact on the future of the exploration project. There are many examples when early on stage exploration, despite the successful identification of a terrane with favorable geological conditions, was doomed to failure due to various factors.
Our success at Oyu Tolgoi did not come instantly. The path to success was thorny. Nosotros describe the obstacles in our mode and how we managed to surmount them. We besides convey the story of the western mining companies' growing interest in the copper potential of Mongolia during the belatedly 1990s and how the Oyu Tolgoi discovery in the South Gobi contributed to this. We are convinced that this historical account volition be of significant value to the reader.
Of course, during the research or desktop written report phase of the program, we fabricated use of the valuable data produced by the previous generations of explorers who conducted regional surveys and geological mapping and pursued their exploration goals in the past. Free access to geological data from The Geological Funds of Mongolia played a critical function stimulating the growth of exploration involvement in the country. We acknowledge the effort of all geologists and mineral experts for their dedicated work and their contribution to the development of the mineral resource base of Mongolia. Their hard work and achievement too contributed to our success.
We believe that publication of the details of the album of this discovery volition provide some insight into the vagaries of the thinking process resulting in the discovery of the most extensive copper porphyry deposit in Mongolia. Without prejudice, nosotros attempted to shed some low-cal on the discoverers' thought process, what decisions we fabricated, and why we fabricated them. Noesis and understanding of how the discovery procedure started will undoubtedly be instructive to them. Hopefully, the lessons conveyed in this book will exist particularly useful to the young geological explorers especially those who are dreaming about their future discoveries.
In the following pages, nosotros also touch upon the makeup and interactions of the diverse exploration team, their psychology, mentality, and how corporate cultures from previous employment affected their decisions. In many ways, the culture has deep roots in the past, playing a pivotal office in everyone's beliefs and attitude toward business. We adopted new approaches in our thinking. In our view, this played a meaning function in our success. At first glance, it appeared that a group as various and multicultural as ours could not work productively. On the opposite, confronting all the odds and skepticism, the team in its determination to evangelize a significant discovery was surprisingly effective. A combination of knowledge and wisdom from veterans and ambitions and aspirations of young geologists worked quite well for us. Neither age nor linguistic communication barriers stopped productive communication. We are not claiming that everything happened smoothly. In that location were challenges. The details of unfolding events of how we managed these various problems on our path to success are the story inscribed on the pages of this volume.
The authors nowadays the events leading to the discovery of Oyu Tolgoi in chronological order. We portray these facts as we meet them afterwards more than 15 years since they took place. We have no ambition to misrepresent the truth, nor practise nosotros intend to claim to accept a magic recipe for success. This book is non a technical written report, nor is it a scientific publication. The use of maps, cross sections, and diagrams, forth with other technical data, helps u.s. to convey our story more clearly.
We promise that while reading this book, the readers will find useful insights and ideas for their ain practical needs. We believe that in the end, this story will facilitate them in their strive for success and consequently will become a useful guide for them toward their discoveries.
During the lifetime of every economical mineral deposit, there is a menses of transition from exploration to product. Ultimately, mineral discoveries are made for the benefit of future metal production. This earth-shaking transitional phase, which tin can make or break the economical viability of a deposit, has many challenges. At Oyu Tolgoi, these bug are currently unfolding in front of our eyes. In 2009 Ivanhoe completed construction of the mining and processing circuitous at Oyu Tolgoi, and Rio Tinto started production in 2010 by expanding the producing complex to its optimum capacity. It may now be timely to reflect on the past and review those initial moments that catapulted Oyu Tolgoi on the path to success.
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Future climates of the world: a modelling perspective
Meinrat O. Andreae , in World Survey of Climatology, 1995
Soil grit
Tremendous amounts of dust are mobilized by loftier winds in the desert regions of the globe, especially the Sahara and Gobi deserts and the Australian deserts. The dust plumes originating from these large deserts are the nearly conspicuous features in maps of the global distribution of atmospheric haze obtained from satellite data ( Husar and Stowe, 1994). While much of this textile, due to the relatively large size of the particles, falls out over again fairly close to its source, substantial amounts are transported over dandy distances. The mass median diameter of this droplets (away from firsthand sources) is of the order of 2 μm, but fifty-fifty "giant" particles, with diameters of l μm or more have been found over the remote oceans, at distances of thousands of kilometres away from their continental sources ( Betzer et al., 1988). Dust from the Gobi desert is easily detected in the Hawaiian Islands, and Saharan dust is consistently observed on the island of Barbados, beyond the Atlantic Ocean. In fact, a large part of the marine sediment in areas remote from the continents is idea to consist of wind-blown grit ( Ferguson et al., 1970; Prospero, 1981; Uematsu et al., 1985). Even in the center of the Amazon Basin during the wet season, dust events from the Sahara have been observed ( Andreae et al., 1990; Artaxo et al., 1990; Talbot et al., 1990; Swap et al., 1992). The amount of dust emitted is difficult to estimate, especially since it is not obvious how this "emission" should be divers: obviously a grain of sand that is just displaced a few centimetres should not be counted, while aerosols that are transported across oceans should be. Still, at that place is a continuous range between these extremes, with the largest masses mobilized having the shortest atmospheric lifetimes, so that the definition of the cutting-off is of great result for the size of the resulting guess.
As a result, estimates of the magnitude of the global flux of soil-grit aerosol vary over a wide range: values every bit low as 100 Tg/yr ( SMIC, 1971) and as high every bit 8000 Tg/year ( Petrenchuk, 1980) tin exist plant in the literature. Duce et al. (1991) nowadays a conscientious analysis of the amount of mineral aerosol deposited to the world ocean; their estimate of 910 Tg/year represents a lower limit to the global flux because much of the soil dust droplets is redeposited on land and does not reach the oceans. Schütz (1987) estimates that the Globe's deserts consign a minimum of 2000 Tg of mineral dust per twelvemonth into the atmosphere, nearly xx% of which is in a size range small enough to be subject to long-range transport and to contribute to the "global groundwork aerosol". In Table I, a range of m–3000 Tg/twelvemonth is proposed equally a reasonable estimate for the global flux of mineral aerosol, and a "best guess" estimate of 1500 Tg/year is suggested. This value agrees with the model results of Wefers (1990), who faux the emission and transport of mineral aerosol using a three-dimensional model (MOGUNTIA), and, at a total source strength of ca. 1500 Tg/year, obtained reasonable agreement between predicted and observed concentrations of mineral aerosol in the remote atmosphere.
The size of the desert regions and the intensity of the winds over them plain accept a great influence on the amounts of dust mobilized, and on the heights to which it is lofted. The desertification of large regions of the African Sahel, the conversion of tropical forests into barely vegetated, degraded lands, and the use of inappropriate agricultural and grazing practices in many regions accept opened considerable soil surface to aeolian erosion and must accept resulted in an increase in the amounts of dust injected into the atmosphere (for a discussion of desertification and land-use change encounter Chapter 12 past Henderson-Sellers in this volume). That such an increase in mineral grit flux due to desertification is already taking place is shown past the concentrations of Saharan grit sampled on Barbados, which show a strong increment from 1965 to 1984, reflecting the drought in the Sahel ( Prospero and Nees, 1986).
Irresolute mineral aerosol burdens have also been associated with climatic alter in the past. Analysis of the mineral aerosol content of Antarctic water ice cores shows elevated levels of soil dust during the ice ages, when large areas on the continental shelves were open to erosion by intense winds over the Southern Hemisphere continents ( Petit et al., 1981; De Angelis et al., 1987). Such an enhanced aerosol burden would contribute to intensified cooling during an ice age.
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Climate change
R.W. Abrams , ... A.L. Abrams , in Encyclopedia of the Anthropocene, 2018
Africa v Rest of Earth: refugia for biodiversity?
Comparisons of biodiversity loss/retentiveness show that the Sahara desert and Congo basin have resisted biodiversity losses, similar to the Amazon basin and Gobi desert ( Newbold et al., 2015). Sure specific habitats are nonetheless within a theoretical "safe limit" with respect to the Biodiversity Intactness Index (BII), including the Greatcoat floristic province and Karoo thickets in South Africa, while Indian Ocean islands including Madagascar and much of East African montane and coastal woods areas along with much of Republic of indonesia and Asia are at or by their "safety limits." In general, temperate, boreal, and polar habitats are more severely impacted in this respect than most of Africa, particularly grasslands, savannahs and much of the tropical regions, which still have not breached their "safe limits." This finding is significant considering people have been living in and using Africa's tropical forests for longer than anywhere else on world (Lewis et al., 2015). In a less happy comparison of socioeconomic parameters for coral reef systems, Eastward Africa presents a dour picture while the Pacific islands are showing slower refuse, due largely to angling and curio collection past coastal communities (Cinner et al., 2016).
In a ranking of progress in regional conservation chance and resource protection in the confront of climate change, the initiatives to conserve nature with responsiveness to climate change pressures are modeled ( Fig. seven ). The southeastern African ecoregion is at risk from industrialization, just Due south Africa in detail is motivated to preserve its ecology ( Fig. 7 ). In Namibia–Okavango–Zambesi–Limpopo ecotone of dense savanna and riverine jungle, the gamble from evolution drops off, and conservation progress is modest though a lack of infrastructure begs growth ( Fig. 7 ). As cardinal Africa gets wetter, it becomes a refuge for species dependent on wetlands, but the region faces conservation crises mostly due to inconsistent policy and enforcement. At the same time, the continent's biodiversity will be narrowed in geographical range by the expanding Sahel and Kalahari deserts as these go hotter. Cohesive direction of natural resources across borders and overriding regional conflicts is a superlative priority if the African continent is to have a biodiverse future, particularly in the Sahel and the equatorial chugalug where warming, water loss, and population growth outcome in resource conservation as a depression priority ( Fig. 7 ).
Fig. 7. (A) Regional assessment of ecological threat from climate alter (High adventure = Scarlet). (B) Regional effort to save biodiversity in response to climate alter (Improved effort = Greenish).
West Africa's due north-south bands of vegetation types range from the Sahara desert, south to the Sahel and savanna and into the moist forests Guinea and on to the Congo basin of Central Africa. Westward Africa has high species endemism in the forests. Conservation International reports xx% of endemic plants, 38% of amphibians, 24% of reptiles, and 21% of endemic mammals worldwide are in West Africa (http://world wide web.biodiversityhotspots.org/xp/hotspots/west_africa/Pages/biodiversity.aspx).
The present-day Sahara occupies an area of slightly over 8 million kmii and transitions to the Sahel, where strong seasonality in rainfall creates a mix of habitats supporting herds of grazing ungulates which are shrinking in the face up of drought and country deposition that is devastating otherwise productive land. West African Savannas, historically highly productive zones, are susceptible to the intertwined activities of agriculture and use of wildlife and forest resources for subsistence livelihoods in the face of growing human numbers (Leadley et al., 2010). These realities demonstrate the crux of the challenge of climatic change in Africa: the richness of nature is juxtaposed to the people's need for food, jobs, and health intendance, demands which take historically depended on extraction (and wise utilise) of natural resources.
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Atmospheric chemistry in Asia: Need of integrated approach
Umesh Kulshrestha , Manisha Mishra , in Asian Atmospheric Pollution, 2022
two.five Eastern asia
East Asian region spreads from north of the Himalayan region, covering China to other small island countries in the e, having similar ethno-culture. Gobi Desert in the western part is the just largest arid area in this region, which is i of the large sources of dust storms that causes poor air quality in the region ( Goudie, 2009). Still, coal combustion and other anthropogenic emissions are the main sources of potential pollution (Chow and Watson, 2008; Li et al., 2014). Information technology has been reported that countries from East asia are receiving mostly transboundary pollution, which is one of the biggest concerns for most of the countries in Eastern asia, which are recently beingness addressed past the dissimilar countries (Aikawa et al., 2010; Nazeer and Furuoka, 2017).
These regions have impacted people living in the region, are a threat to man health, and need urgent attention. The local and regional problems touch on the global bug. Asia is too facing the problem of global issues such as global warming and climate change.
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Third Field Season—Prospecting for Copper Porphyry Systems
Sergei Diakov , ... Galsan Jamsrandorj , in Discovery of Oyu Tolgoi, 2019
3.2 Khanbogd Complex
The copper prospect we were to visit was located in close proximity to the Khanbogd Complex, which is a prominent, circular topographic feature in the southern part of the Gobi Desert, conspicuous on satellite images.
The Khanbogd Complex is the largest, massive, alkaline intrusive rocks in Mongolia occupying an area of 1,500 foursquare kilometers. The complex is Permian in age and represents an intrusion of blazon An ultraalkaline granitoids enriched in zirconium, niobium, and rare world elements (Kovalenko et al., 1995). All ultraalkaline complexes manifest both textural and geochemical evidence that hydrothermal fluids send rare world elements. The formation of the complex is believed to exist either acquired by a mantle plume or melting in the asthenosphere from the standoff of the Siberian and north-Chinese platforms (Yarmolyuk, Kovalenko, 2002). Such a procedure causes the formation of an unusual paragenesis of zirconium silicate minerals.
The Khanbogd Circuitous tin can be subdivided into an eastern and western half. The Paleozoic historic period Tsokiot volcanogenic sedimentary circuitous hosts the ultraalkaline granitoids. The ultraalkaline granites that occur in the western half of the complex accept an historic period date of 292–283 Ma (Kovalenko et al., 2006). This unit of measurement is medium- and coarse-grained consisting of 48%–50% quartz, up to 35% potassium feldspar, upwards to 11% of aegirine, and up to 12% of arfvedsonite. Widespread replacement of arfvedsonite by aegirine forms radial growth structures (Figs. three.i and three.two). Accessory minerals are zirconium silicates, apatite, rutile, and titanite.
Effigy iii.1. D. Garamjav in front of the outcrops of Khanbogd Circuitous belongings samples with arfvedsonite.
Figure iii.2. Khanbogd Complex. Clusters with arfvedsonite.
Inside the Khanbogd Complex, there is also a younger phase of biotite granite dated at 272 Ma (Kovalenko et al., 2006) and numerous circumvolve-shaped ring dikes and radial-shaped dikes.
Upon arrival at the reconnaissance camp in the Khanbogd Complex, Sergei was given an update on the reconnaissance plan and, in item, on the copper showing associated with copper porphyry manner alteration. While conducting reconnaissance in the Khanbogd Complex vicinity, the team attempted to revisit some of the copper showings that D. Garamjav had seen on a previous mapping project. During the search, the team found a hill composed of intensely silicified rocks. Hither the team noted numerous leached cavities in quartz stockwork veins. Co-ordinate to D. Cox, this outcrop had the appearance of a typical cap rock over the leached porphyry systems.
Early on in the morn, the team drove to the hill of silicified rocks about 60 km from the camp. The landscape is a flat sandy and stony desert obviously with thin shrubs and periodic hills, which is typical for the Gobi Desert. Most notable in the surface area is a table mountain named Javhalant (Fig. iii.3) about 18 km southwest of the silicified hills. There are petroglyphs depicting animals—evidence of ancient nomads who once inhabited this area. Granitoids at the peak of Javhalant are dated 324 ± 2 Ma (Gerel et al., 2005).
Effigy 3.3. Typical Gobi landscape around Oyu Tolgoi; the table mountain Javhalant is in the background.
The silicified hill was nondescript, rising a few tens of meters above the Gobi desert. The hill was about 150 m across and was equanimous of volcanic rocks of andesitic and andesite-dacitic composition with intense silicification–argillization and some sericite—all saturated with quartz veins. Quartz veins contained numerous voids, indicating the previous presence of sulfides. The ubiquitous distribution of brownish limonite and hematite was an show for copper sulfide mineralization, which was consequently leached and so moved in a soluble grade from the surface to lower horizons. Moreover, the presence of hematite suggested that a chalcocite blanket had been formed by this process and was moved at least several times being ultimately deposited at depth beneath the hill.
Usually a black manganese oxide tarnish covers the stones scattered across the desert, which can conceal evidence of surficial alteration. When viewed with the center of an practiced, the presence of a whitish surficial stain acquired by dirt and kaolin with limonite could distinguish this hill from other like mounds in the region. The alteration zone was more than noticeable from aeriform views (Fig. 3.4) and was afterwards confirmed with Landsat satellite imagery due to an unusual range of colors seen on the images compared to other unaltered rock outcrops of volcanic rock. Interestingly, on the southeastern cease of the hill, at the foot, there was a small clearing under 20 m in bore covered with green grass growing in the desert, which was a clear sign of the presence of groundwater at a shallow depth. This "birthmark" was very characteristic for this hill and was easily recognizable on all remote-sensing images.
Figure three.4. Bird's-center view of Central Oyu with strongly contradistinct rocks forming a visible color bibelot among the gentle hills in the Gobi. On the correct, there is a distinct vegetation anomaly.
Garamjav plant the copper in a small digging past most one-half-meter deep and nigh two m in diameter. According to Garamjav, this small pit indicated a possibility for some aboriginal copper mining. This copper showing was named Oyu Tolgoi or Turquoise Colina because of the presence of crusts of chrysocolla and malachite. Although we did not find turquoise itself, due to similarity in colors and the abundant presence of magnetite with chlorite, the andesite volcanic rocks looked very dark, almost blackness. With this background, chrysocolla was clearly noticeable, so the proper name of Oyu Tolgoi was quite appropriate.
The mineralized outcrop in the southwest was named Due south-West Oyu, and the hill of silicified volcanics was named Central Oyu (Fig. 3.5). Nonetheless, in westward-cardinal Oyu, at that place was a zone of mineralization different in nature due to numerous thin quartz–magnetite ± pyrite veins within intensely chloritized volcanics. This outcrop was given the name West Oyu (Fig. 3.6). West Oyu, unlike Cardinal Oyu, did non feel any meaning leaching, which indicated that the occurrence of copper mineralization had a somewhat unlike paragenesis.
Figure 3.v. Quartz stockwork (A) and limonite-hematitic iron oxides (B) at Primal Oyu.
Effigy 3.6. Copper oxides in the form of chrysocolla (A) at South-Westward Oyu and outcrops of quartz-magnetite stockwork (B) at West Oyu Tolgoi.
Traversing to the northeast of Fundamental Oyu revealed that behind the silicified hill of Central Oyu, at a altitude of about 300 m, at that place was a small volcanic hill. Recent clay covers further extension of volcanic rocks to the due north. Like volcanic rocks in this loma also diameter signs of weak hydrothermal alterations in the course of chlorite–pyritic associations that might be a office of the overall propylitic alteration around the porphyry systems. The loma received a name North Oyu.
Field observations revealed the presence of numerous outcrops with copper mineralization associated with various types of amending that pointed to the presence of a previously unrecognized porphyry copper organization. This was a fascinating development, and it was obvious that this surface area deserved further attention and exploration to assess its mineral potential.
Furthermore, Oyu Tolgoi hosted several centers with porphyry mineralization, which could coagulate into a major system at depth. Presence of sings of secondary sulfide enrichment raised the spectra of hope that not only the target of scale could be achieved but likewise that the copper tenor could be profoundly enhanced. Although it was somewhat premature to speculate, but peradventure this prospect, plant and so early in this exploration program, could meet the challenging target goals that BHP was pursuing in Mongolia.
Also noteworthy was that in the Oyu Tolgoi hills, absolutely no prove of modern exploration had been found. This meant it was a "virgin" unassessed prospect with good exploration prospectivity. No dubiety, it was urgent to "pale" the ground and apply for an exploration license.
After visiting this prospect and recording the presence of leached stockwork there and the widespread distribution of porphyry fashion alteration, it became clear that Oyu Tolgoi has a potential to become a leading copper project amongst all other copper prospects nosotros had seen in Mongolia. Oyu Tolgoi seemed to take the key attributes of a promising porphyry-type organisation that the previous Erdenet-Magma JV and so BHP had been seeking.
It was now urgent that BHP apply for an exploration license. To delineate the license boundaries, a quick reconnaissance around Oyu Tolgoi was conducted. To the n, at Shivee Ovoo, we discovered altered volcanics. After visiting several outcrops to the due south, the limits of the license surface area were adamant with a good degree of confidence.
In addition to Oyu Tolgoi, another prospect in the Southern Gobi, Ih Shankh, (Fig. 3.7) also demonstrated quite encouraging alteration features. Based on the reconnaissance results, Ih Shankh contained several zones of intense argillic alteration with the development of alunite and hematite, accompanied by noticeable quartz stockworks and occasional individual quartz veins.
Figure iii.vii. D. Garamjav in the process of mapping one of the outcrops of Ih Shankh.
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Concentrating Solar Power☆
B. Hoffschmidt , ... P. Hilger , in Reference Module in Globe Systems and Environmental Sciences, 2021
v.1.13 Shouhang Dunhuang
The Shouhang Dunhuang molten table salt solar tower power plant is the largest CSP plant in operation in China until date. The ability plant is located in China, 25 km abroad from Dunhuang, in the Gansu Province, virtually the Gobi desert ( Shouhang European, n.d.). The plant, which started construction on November 2015, has been operational since December 2022 and can generate upwardly to 390,000 MWha− 1 (NREL, northward.d.). It possesses a 2-tank molten salt storage with a capacity of 11 h at full load. The hot tank contains molten salt at 565 °C and the common cold tank at 290 °C. The heat from the molten common salt loop is transferred to a water-steam cycle to produce 550 °C superheated steam, which drives a turbine with a capacity of 100 MWe. The CSP plant contains a 263 thou tower and 12,000 heliostats with a size of 115 chiliadtwo each (see Fig. 49) (CSPPlaza, 2018). The plant was adult and constructed by Beijing Shouhang IHW Resources Saving Technology Company Ltd. (CSPPlaza, 2019a).
Fig. 49. Shouhang Dunhuang 100 MWe central receiver ability plant (2018). A ten MWe sit-in plant is located side by side to the 100 MWe power institute.
Source: CSPFocus.The Shouhang Dunhuang CSP plant is i of the twenty projects of the Chinese CSP demonstration program's first circular. The Chinese demonstration programme includes fundamental receiver, parabolic trough collector and Fresnel technologies.
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Atmospheric Chemistry1
John K. Wallace , Peter V. Hobbs , in Atmospheric Science (Second Edition), 2006
5.4.three Transport
Aerosols are transported by the airflows they see during the time they spend in the atmosphere. The transport can exist over intercontinental, fifty-fifty global, scales. Thus, Saharan grit is transported to the Americas, and grit from the Gobi Desert can reach the westward coast of North America. If the aerosols are produced by one thousand-to-p conversion, long-range ship is likely because the time required for thousand-to-p conversion and the relatively small-scale sizes of the particles produced past this process pb to long residence times in the temper. This is the example for sulfates that derive from Then ii blasted into the stratosphere by big volcanic eruptions. It is also the instance for acidic aerosols such as sulfates and nitrates, which contribute to acid pelting. Thus, So2 emitted from ability plants in the Britain can be deposited every bit sulfate far inland in continental Europe.
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