Baja California Sur
Before becoming a state on October 8,1974, the area was known as the South Territory of Baja California. It is bordered to the north by the state of Baja California, to the west by the Pacific Ocean, the state has maritime borders with Sonora and Sinaloa to the east, across the Gulf of California. The state is home to the tourist resorts of Cabo San Lucas and its largest city and capital is La Paz. The state is the part of the Baja California Peninsula. With a territory of 73,909 km², it is about 750 km long, the state is divided into five municipalities. Comondú is located in the center of the state with its seat at Ciudad Constitución and it borders the municipalities of Mulegé, Loreto and La Paz with the Pacific Ocean to the west. Mulegé is in the north of the state with its capital in Santa Rosalía and it borders the municipalities of Comondú and Loreto with Baja California Norte to the north, the Pacific Ocean to the west and the Gulf of California to the east. It accounts for almost 45% of the state’s territory, the municipality of La Paz is in the south of the state.
It is the second largest municipality, accounting for just over 27% of the territory of the state and it borders the municipalities of Comondú and Los Cabos and extends from the Pacific Ocean to the Gulf of California. The municipality of Los Cabos is at the tip of the state, with its seat at San José del Cabo. The municipality is one of the most important tourist destinations in Mexico, the municipality borders that of La Paz to the north, with the rest defined by the Pacific Ocean and the Gulf of California. The municipality of Loreto is in the center of the state and it borders the municipalities of Mulegé and Comondú with the Gulf of California to the east. Its major cities are La Paz, San Jose del Cabo, Ciudad Constitución, Santa Rosalia, the territory is primarily mountains or mountain ranges and coastal plains. The mountain ranges parallel the coastline and are of volcanic rock, the local name for the main mountain range is the Sierra de la Giganta and the highest peak is the Sierra de la Laguna at 2080m above sea level.
The coastal plains are significantly wider on the Pacific side, averaging about 40 km, with much wider plains such as those of Santa Clara and these areas are dominated by sedimentary rock, especially limestone of marine origin. The state is divided into five regions, Central Desert, La Serranía, the Vizcaíno Desert, the Central Desert has desert plants, with vegetation springing up during short and irregular rains. The La Serranía is the mountain areas with significant tree cover. The Magdalena Plains is a large, flat area near the Pacific coast, the climate of the state is dry, with an average annual temperature of 18–22°C and average annual rainfall of less than 200mm
The Aralkum Desert is a desert that has appeared since 1960 on the seabed once occupied by the Aral Sea. It lies to the south and east of what remains of the Aral Sea in Uzbekistan and Kazakhstan. While the level of the Aral Sea has fluctuated over its existence, the severely reduced inflow subsequently caused the water level in the Aral Sea to drop. While the North Aral Sea is rising due to a dike, the South Aral Sea kept dropping, thus expanding the size of the desert, until 2010, the water level of the South Aral Sea began to drop again, this time more severely. The sands of the Aralkum and the dust that originates from it contain pollutants, the deserts location on a powerful east-west airstream has resulted in pesticides in the dust being found in the blood of penguins in Antarctica. Aral dust has found in the fields of Russia, the forests of Norway. Desertification List of environmental disasters Siegmar-W, Combating desertification and rehabilitation of the salt deserts in the region at the Aral Sea Walter Wucherer, Primary succession on the dry sea floor of the Aral Sea
Badain Jaran Desert
The Badain Jaran Desert is a desert in China which spans the provinces of Gansu and Inner Mongolia. It covers an area of 49,000 square kilometres, by size it is the third largest desert in China. This desert is home to some of the tallest stationary dunes on Earth, with some reaching a height of more than 500 meters and its tallest dune is measured, from base to peak, as the worlds third tallest dune and highest stationary dune in the world. The desert features over 100 spring-fed lakes that lie between the dunes, some of which are fresh water while others are extremely saline and these lakes give the desert its name which is Mongolian for mysterious lakes. It is crossed by one river, the Ruo Shui, located in the Alxa Plateau at about 1200 meters above sea level it is listed as a subsection to the Gobi Desert. With these dunes only the surface of the sand is constantly shifting. The middle and lower layers of the highest dunes have been compacted for more than 20,000 years causing the particles to harden resulting in solid layers of sand.
High moisture levels inside the dunes contribute to maintain their fixed state and this rigid structure allows peaks, cliffs and even caves to form as a result of water erosion and desertification. The Badain Jaran Desert, like the Tengger Desert which lies to the east is about one-half barren, sandy desert and one-half a mixture of solid bedrock, several small lakes and oases scatter the desert around which limited vegetation is able to grow. The Badain Jaran Desert is well known for its numerous scattered, containing more than 140 lakes they are mainly found in the southern region in the desert. These lakes can easily be found in the valleys between large dunes. They are believed to provide the life sustenance in the desert supporting camels, most lakes support a green ring of vegetation that populate the close vicinity around the lakes. Throughout the desert some lakes change color due to populations of algae, Brine shrimp. Evaporation can allow others to turn into a lake forming a salt crust around the rim of the lake.
Although their true sources are still debated it is believed that they are being maintained by underground water streams, most arid deserts in China are surrounded by mountains that provide water sources, and this is the case with the Badain Jaran Desert. Runoff from the mountains is collected through gravel deposits and this allows them to run through the desert, within the desert there can be two main types of lakes found regarding their morphometry. The largely elongated shallow lakes mainly appear in the area in the southeastern margin of the desert. Their depth often reaches less than 2 meters and only measure about.2 square kilometres, the oval-shaped, deep lakes can be found in the compound transverse megadune area
It is the hottest desert in Mexico. It has an area of 260,000 square kilometers, the western portion of the United States–Mexico border passes through the Sonoran Desert. In phytogeography, the Sonoran Desert is within the Sonoran Floristic Province of the Madrean Region in southwestern North America, the desert contains a variety of unique and endemic plants and animals, such as the saguaro and organ pipe cactus. It is bounded on the west by the Peninsular Ranges, which separate it from the California chaparral and woodlands, to the north in California and northwest Arizona, the Sonoran Desert transitions to the colder-winter, higher-elevation Mojave, Great Basin, and Colorado Plateau deserts. To the east and southeast, the transition to the coniferous Arizona Mountains forests and Sierra Madre. To the south the Sonoran–Sinaloan transition subtropical dry forest is the zone from the Sonoran Desert to the tropical dry forests of the Mexican state of Sinaloa. The deserts sub-regions include the Colorado Desert of southeastern California, many ecologists now consider Shreves Vizcaíno and Magdalena regions, which lie on the western side of the Baja California Peninsula, to be a separate ecoregion, the Baja California Desert.
The Pinacate National Park includes the only active Erg dune region in North America, the nearest city to the Reserva de la Biosfera el Pinacate y Gran Desierto de Altar is Puerto Peñasco in the state of Sonora, Mexico. The Sonoran Desert area southeast of Tucson and near the Mexican border is vital habitat for the population of jaguars living within the United States. Many plants not only survive, but thrive in the conditions of the Sonoran Desert. Many have evolved to have specialized adaptations to the desert climate, the Sonoran Deserts biseasonal rainfall pattern results in more plant species than any other desert in the world. The Sonoran Desert includes plant genera and species from the family, palm family, cactus family, legume family. The Sonoran is the place in the world where the famous saguaro cactus grows in the wild. Cholla, hedgehog, prickly pear, nightblooming cereus, creosote bush and bur sage dominate valley floors. Indigo bush and Mormon tea are other shrubs that may be found, wildflowers of the Sonoran Desert include desert sand verbena, desert sunflower, and evening primroses.
Ascending from the valley up bajadas, various such as velvet mesquite, palo verde, desert ironwood, desert willow. Shrubs found at higher elevations include whitethorn acacia, fairy duster, in the desert subdivisions found on Baja California, cardon cactus, elephant tree, and boojum tree occur. The California fan palm is found in the Colorado Desert section of the Sonoran Desert and it is found at spring-fed oases, such as in Anza Borrego Desert State Park, Joshua Tree National Park, and the Kofa National Wildlife Refuge
An ecoregion is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than an ecozone. All three of these are less or greater than an ecosystem. Ecoregions cover relatively large areas of land or water, and contain characteristic, the biodiversity of flora and ecosystems that characterise an ecoregion tends to be distinct from that of other ecoregions. Three caveats are appropriate for all bio-geographic mapping approaches, firstly, no single bio-geographic framework is optimal for all taxa. Ecoregions reflect the best compromise for as many taxa as possible, ecoregion boundaries rarely form abrupt edges, rather and mosaic habitats bound them. Thirdly, most ecoregions contain habitats that differ from their assigned biome, biogeographic provinces may originate due to various barriers. Some physical, some climatic and some ocean chemical related, the history of the term is somewhat vague as it was used in many contexts, forest classifications, biome classifications, biogeographic classifications, etc.
The concept of ecoregion of Bailey gives more importance to ecological criteria, while the WWF concept gives more importance to biogeography, there is significant, but not absolute, spatial correlation among these characteristics, making the delineation of ecoregions an imperfect science. Such transition zones are called ecotones, Ecoregions can be categorized using an algorithmic approach or a holistic, “weight-of-evidence” approach where the importance of various factors may vary. An example of the approach is Robert Bailey’s work for the U. S. The intended purpose of ecoregion delineation may affect the method used, according to WWF, the boundaries of an ecoregion approximate the original extent of the natural communities prior to any major recent disruptions or changes. WWF has identified 867 terrestrial ecoregions, and approximately 450 freshwater ecoregions across the Earth, the use of the term ecoregion is an outgrowth of a surge of interest in ecosystems and their functioning. In particular, there is awareness of issues relating to spatial scale in the study and it is widely recognized that interlinked ecosystems combine to form a whole that is greater than the sum of its parts.
The Global 200 is the list of ecoregions identified by WWF as priorities for conservation, Terrestrial ecoregions are land ecoregions, as distinct from freshwater and marine ecoregions. In this context, terrestrial is used to mean of land, WWF ecologists currently divide the land surface of the Earth into 8 major ecozones containing 867 smaller terrestrial ecoregions. The WWF effort is a synthesis of previous efforts to define. Many consider this classification to be decisive, and some propose these as stable borders for bioregional democracy initiatives. The eight terrestrial ecozones follow the major floral and faunal boundaries, identified by botanists and zoologists, ecozone boundaries generally follow continental boundaries, or major barriers to plant and animal distribution, like the Himalayas and the Sahara
Dasht-e Loot, spelled Dasht-i-Loot and known as the Loot Desert, is a large salt desert in Kerman and Sistan and Baluchistan Province, Iran and is the worlds 25th largest desert. The surface of the sand there has been measured at temperatures as high as 70 °C and it was inscribed to the UNESCO World Heritage Sites list on July 17,2016. Iran is climatically part of the Afro-Asian belt of deserts, which stretches from the Cape Verde islands off West Africa all the way to Mongolia near Beijing, China. The patchy, light-colored feature in the foreground is the northernmost of the Dasht dry lakes that stretch southward 300 kilometers, in near-tropical deserts, elevated areas capture most precipitation. As a result, the desert is largely an abiotic zone, irans geography consists of a plateau surrounded by mountains and divided into drainage basins. Dasht-e Loot is one of the largest of these basins,480 kilometers long and 320 kilometers wide. Area of the desert is about 51,800 square kilometres, the other large basin is the Dasht-e Kavir.
During the spring wet season, water flows down from the Kerman mountains, but it soon dries up, leaving behind only rocks, sand. The eastern part of Dasht-e Loot is a low plateau covered with salt flats, in contrast, the center has been sculpted by the wind into a series of parallel ridges and furrows, extending over 150 km and reaching 75 metres in height. This area is riddled with ravines and sinkholes. The southeast is a vast expanse of sand, like a Saharan erg, with dunes 300 metres high, precision of measurements is 0.5 K to 1 K. The hottest part of Dasht-e Loot is Gandom Beryan, a plateau covered in dark lava. According to a legend, the name originates from an accident where a load of wheat was left in the desert which was scorched by the heat in a few days. Dasht-e Kavir Geography of Iran International rankings of Iran Sykes, Percy, NASA image and info NASA survey on temperatures around the globe
Desertification is a type of land degradation in which relatively dry area of land becomes increasingly arid, typically losing its bodies of water as well as vegetation and wildlife. It is caused by a variety of factors, such as climate change. Desertification is a significant global ecological and environmental problem, considerable controversy exists over the proper definition of the term desertification for which Helmut Geist has identified more than 100 formal definitions. Another major contribution to the controversy comes from the sub-grouping of types of desertification, the worlds most noted deserts have been formed by natural processes interacting over long intervals of time. During most of times, deserts have grown and shrunk independent of human activities. Paleodeserts are large sand seas now inactive because they are stabilized by vegetation, some extending beyond the present margins of deserts, such as the Sahara. Drylands occupy approximately 40–41% of Earth’s land area and are home to more than 2 billion people.
As of 1998, the then-current degree of expansion of the Sahara was not well known, due to a lack of recent. Causes of desertification in Sahel, The impact of global warming, in this area, the level of desertification is very high compared to other areas in the world. All areas situated in the part of Africa are characterized by a dry climate, hot temperatures. So, droughts are the rule in the Sahel region, development of the desertification process in Sahel, Some studies have shown that Africa has lost approximately 650000 km² of its productive agricultural land over the past 50 years. The propagation of desertification in this area is considerable, Some statistics have shown that since 1900, the Sahara has expanded by 250 km, covering an additional area of 6000 square kilometers. Impacts of desertification in Sahel, The survey, done by the institute for development, had demonstrated that this dryness is spreading fast in the Sahelian countries. Desertification in the Sahel can affect more than one billion of its inhabitants, 70% of the arid area has deteriorated and water resources have disappeared, leading to soil degradation.
The loss of topsoil means that plants take root firmly. The United Nations Convention says that six million Sahelian citizens would have to give up the desertified zones of sub-Saharan Africa for North Africa. As the desertification takes place, the landscape may progress through different stages, on gradually sloped terrain, desertification can create increasingly larger empty spaces over a large strip of land, a phenomenon known as Brousse tigrée. A mathematical model of this phenomenon proposed by C, klausmeier attributes this patterning to dynamics in plant-water interaction
They have a specialized non-lignified tissue to conduct products of photosynthesis. Vascular plants include the clubmosses, ferns and angiosperms, scientific names for the group include Tracheophyta and Tracheobionta. Vascular plants are distinguished by two characteristics, Vascular plants have vascular tissues which distribute resources through the plant. This feature allows vascular plants to evolve to a larger size than non-vascular plants, in vascular plants, the principal generation phase is the sporophyte, which is usually diploid with two sets of chromosomes per cell. Only the germ cells and gametophytes are haploid, by contrast, the principal generation phase in non-vascular plants is the gametophyte, which is haploid with one set of chromosomes per cell. In these plants, only the spore stalk and capsule are diploid, in other words, elaboration of the spore stalk enabled the production of more spores, and enabled the development of the ability to release them higher and to broadcast them farther.
Such developments may include more photosynthetic area for the structure, the ability to grow independent roots, woody structure for support. A proposed phylogeny of the plants after Kenrick and Crane is as follows. Pteridophyta from Smith et al. and lycophytes and ferns by Christenhusz et al and this phylogeny is supported by several molecular studies. Other researchers state that taking fossils into account leads to different conclusions and nutrients in the form of inorganic solutes are drawn up from the soil by the roots and transported throughout the plant by the xylem. Organic compounds such as produced by photosynthesis in leaves are distributed by the phloem sieve tube elements. The xylem consists of vessels in flowering plants and tracheids in other vascular plants, a tracheid cell wall usually contains the polymer lignin. The phloem however consists of living cells called sieve-tube members, between the sieve-tube members are sieve plates, which have pores to allow molecules to pass through.
Sieve-tube members lack such organs as nuclei or ribosomes, but cells next to them, the most abundant compound in all plants, as in all cellular organisms, is water which serves an important structural role and a vital role in plant metabolism. Transpiration is the process of water movement within plant tissues. Water is constantly transpired from the plant through its stomata to the atmosphere, the movement of water out of the leaf stomata creates a transpiration pull or tension in the water column in the xylem vessels or tracheids. The pull is the result of surface tension within the cell walls of the mesophyll cells. The draw of water upwards may be passive and can be assisted by the movement of water into the roots via osmosis
A desert is a barren area of land where little precipitation occurs and consequently living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to the processes of denudation, about one third of the land surface of the world is arid or semi-arid. This includes much of the regions where little precipitation occurs. Deserts can be classified by the amount of precipitation falls, by the temperature that prevails. Deserts are formed by weathering processes as large variations in temperature between day and night put strains on the rocks which consequently break in pieces, although rain seldom occurs in deserts, there are occasional downpours that can result in flash floods. Rain falling on hot rocks can cause them to shatter and the resulting fragments and this picks up particles of sand and dust and wafts them aloft in sand or dust storms. Wind-blown sand grains striking any solid object in their path can abrade the surface, rocks are smoothed down, and the wind sorts sand into uniform deposits.
The grains end up as level sheets of sand or are piled high in billowing sand dunes, other deserts are flat, stony plains where all the fine material has been blown away and the surface consists of a mosaic of smooth stones. These areas are known as desert pavements and little further erosion takes place, other desert features include rock outcrops, exposed bedrock and clays once deposited by flowing water. Temporary lakes may form and salt pans may be left when waters evaporate, there may be underground sources of water in the form of springs and seepages from aquifers. Where these are found, oases can occur and animals living in the desert need special adaptations to survive in the harsh environment. Plants tend to be tough and wiry with small or no leaves, water-resistant cuticles, some annual plants germinate and die in the course of a few weeks after rainfall while other long-lived plants survive for years and have deep root systems able to tap underground moisture. Animals need to cool and find enough food and water to survive.
Many are nocturnal and stay in the shade or underground during the heat of the day and they tend to be efficient at conserving water, extracting most of their needs from their food and concentrating their urine. Some animals remain in a state of dormancy for long periods and they reproduce rapidly while conditions are favorable before returning to dormancy. People have struggled to live in deserts and the surrounding lands for millennia. Nomads have moved their flocks and herds to wherever grazing is available, the cultivation of semi-arid regions encourages erosion of soil and is one of the causes of increased desertification. Many trade routes have been forged across deserts, especially across the Sahara Desert, large numbers of slaves were taken northwards across the Sahara
The Cholistan Desert, locally known as Rohi, sprawls 30 km from Bahawalpur, Punjab and covers an area of 26,300 km2. It adjoins the Thar Desert, extending over to Sindh and into India, the word Cholistan is derived from the Turkic word chol, meaning desert. The people of Cholistan lead a life, moving from one place to another in search of water and fodder for their animals. The dry bed of the Hakra River runs through the area, the desert hosts an annual Jeep rally, known as Cholistan Desert Jeep Rally. It is the biggest motor event in Pakistan. In a harsh and barren land where rainfall is sparse and unreliable, Cholistanis rely mainly on their livestock of sheep, goats. However, in nights of winter they huddle indoor and engage themselves in various arts and crafts such as textiles, leatherwork. Cholistan till the era of Mughal rule had been isolated from outside influence, during the rule of Mughal Emperor Akbar, it became a proper productive unit. The entire area was ruled by a host of kings who securely guarded their frontiers, the rulers were the great patrons of art, and the various crafts underwent a simultaneous and parallel development, influencing each other.
Masons, stone carvers, artisans and designers started rebuilding the old cities and new sites, and with that flourished new courts, weaving, the fields of architecture, terra cotta, and pottery developed greatly in this phase. The backbone of Cholistan economy is cattle breeding and it has the major importance for satisfying the areas major needs for cottage industry as well as milk meat and fat. Because of the way of life the main wealth of the people are their cattle that are bred for sale. Moreover, isolated as they were, they had to depend upon themselves for all their needs like food, clothing, so all their crafts initially stemmed from necessity but on they started exporting their goods to the other places as well. The estimated number of livestock in the areas is 1.6 million. Cholistan produces very superior type of wool as compared to that produced in other parts of Pakistan. From this wool they knit beautiful carpets and other woolen items and this includes blankets, which is a local necessity for the desert is not just a land of dust and heat, but winter nights here are very cold, usually below freezing points.
Khes and pattu are manufactured with wool or cotton, khes is a form of blanket with a field of black white and pattu has a white ground base. Cholistanis now sell the wool for it brings maximum profit and it may be mentioned that cotton textiles have always been a hallmark of craft of Indus valley civilization
A shrub or bush is a small to medium-sized woody plant. It is distinguished from a tree by its multiple stems and shorter height, plants of many species may grow either into shrubs or trees, depending on their growing conditions. Small, low shrubs, generally less than 2 m tall, such as lavender, periwinkle, an area of cultivated shrubs in a park or a garden is known as a shrubbery. When clipped as topiary, suitable species or varieties of shrubs develop dense foliage, many shrubs respond well to renewal pruning, in which hard cutting back to a stool results in long new stems known as canes. Other shrubs respond better to selective pruning to reveal their structure, shrubs in common garden practice are generally considered broad-leaved plants, though some smaller conifers such as mountain pine and common juniper are shrubby in structure. Species that grow into a shrubby habit may be deciduous or evergreen