question_text: where is the great sand dunes national park located

text: History[edit]

text: The oldest evidence of humans in the area dates back about 11,000 years. Some of the first people to enter the San Luis Valley and the Great Sand Dunes area were nomadic hunter-gatherers whose connection to the area centered around the herds of mammoths and prehistoric bison. They were Stone Age people who hunted with large stone spear or dart points now identified as Clovis and Folsom points. These people only stayed when hunting and plant gathering was good, and avoided the region during times of drought and scarcity.[11]

text: Modern American Indian tribes were familiar with the area when Spaniards first arrived in the 17th century. The traditional Ute phrase for the Great Sand Dunes is Saa waap maa nache, "sand that moves." Jicarilla Apaches settled in northern New Mexico and called the dunes Sei-anyedi, "it goes up and down." Blanca Peak, just southeast of the dunes, is one of the four sacred mountains of the Navajo, who call it Sisnaajini. These various tribes collected the inner layers of bark from ponderosa pine trees for use as food and medicine. The people from the Tewa/Tiwa-speaking pueblos along the Rio Grande remember a traditional site of great importance located in the valley near the dunes: the lake through which their people emerged into the present world. They call the lake Sip'ophe, meaning "Sandy Place Lake", which is thought to be the springs and/or lakes immediately west of the dunefield.[11]

text: In 1694, Don Diego de Vargas became the first European known to have entered the San Luis Valley, although herders and hunters from the Spanish colonies in present-day northern New Mexico probably entered the valley as early as 1598. De Vargas and his men hunted a herd of 500 bison in the southern part of the valley before returning to Santa Fe. In 1776, Juan Bautista de Anza and an entourage of men and livestock probably passed near the dunes as they returned from a punitive raid against a group of Comanches. At this time, the valley was a travel route between the High Plains and Santa Fe for Comanches, Utes, and Spanish soldiers. The dunes were likely a visible landmark for travelers along the trail.[11]

text: The first known writings about Great Sand Dunes appear in Zebulon Pike’s journals of 1807. As Lewis and Clark’s expedition was returning east, U.S. Army Lt. Pike was commissioned to explore as far west as the Arkansas and Red Rivers. By the end of November 1806, Pike and his men had reached the site of today’s Pueblo, Colorado. Still pushing southwest, and confused about the location of the Arkansas River, Pike crossed the Sangre de Cristos just above the Great Sand Dunes.[11]

text: After marching some miles, we discovered ... at the foot of the White Mountains [today’s Sangre de Cristos] which we were then descending, sandy hills…When we encamped, I ascended one of the largest hills of sand, and with my glass could discover a large river [the Rio Grande] …The sand-hills extended up and down the foot of the White Mountains about 15 miles, and appeared to be about 5 miles in width. Their appearance was exactly that of the sea in a storm, except as to color, not the least sign of vegetation existing thereon.

text: In 1848, John C. Frémont was hired to find a railroad route from St. Louis to California. He crossed the Sangre de Cristos into the San Luis Valley in winter, courting disaster but proving that a winter crossing of this range was possible. He was followed in 1853 by Captain John Gunnison of the Corps of Topographical Engineers. Gunnison’s party crossed the dunefield on horseback.[11]

text: In the years that followed, the Rockies were gradually explored, treaties were signed and broken with resident tribes, and people with widely differing goals entered the San Luis Valley from the United States and Mexico. In 1852, Fort Massachusetts was built and then relocated to Fort Garland, about 20 miles southeast of the Great Sand Dunes, to safeguard travel for settlers following the explorers into the valley. Although many settlers arrived via the trails from Santa Fe or La Veta Pass, several routes over the Sangre de Cristos into the valley were well-known to American Indians and increasingly used by settlers in the late 1800s. Medano Pass, also known as Sand Hill Pass, and Mosca Pass, also called Robidoux’s Pass, offered more direct routes from the growing front range cities and dropped into the valley just east of the Great Sand Dunes. Trails were improved into wagon routes and eventually into rough roads. The Mosca Pass Toll Road was developed in the 1870s, and stages and the mail route used it regularly through about 1911 when the western portion was damaged in a flash flood. Partially rebuilt at times in the 1930s through the 1950s, the road was repeatedly closed due to flood damage and is now a hiking trail.[11]

text: The Herard family—after whom Mount Herard is named[17]—established a ranch and homestead along Medano Creek in 1875, using the old Medano Pass Road to travel to and from their home. The modern unpaved road follows the old route and is open only to four-wheel drive, high-clearance vehicles as it passes through deep sand, rises to Medano Pass, and continues east into the Wet Mountain Valley. The Herards grazed and bred cattle in the mountain meadows, raised horses, and established a trout hatchery in the stream. Other families homesteaded near the dunes as well, including the Teofilo Trujillo family whose sheep and cattle ranch in the valley later became part of the Medano–Zapata Ranch, owned by the Nature Conservancy since 1999. The Trujillo's extant homestead and the ruins of a destroyed one were declared a National Historic Landmark in 2004.[18] Frank and Virginia Wellington built a cabin and hand-dug the irrigation ditch that parallels Wellington Ditch Trail located south of the park campground.[11]

text: Gold and silver rushes occurred around the Rockies after 1853, bringing miners by the thousands into the state and stimulating mining businesses that are still in operation. Numerous small strikes occurred in the mountains around the San Luis Valley. People had frequently speculated that gold might be present in the Great Sand Dunes, and local newspapers ran articles in the 1920s estimating its worth at anywhere from 17 cents/ton to $3/ton. Active placer mining operations sprang up along Medano Creek, and in 1932 the Volcanic Mining Company established a gold mill designed to recover gold from the sand. Although minute quantities of gold were recovered, the technique was too labor-intensive, the stream too seasonal, and the pay-out too small to support any business for long.[11]

text: The idea that the dunes could be destroyed by gold mining or concrete manufacturing alarmed residents of Alamosa and Monte Vista. By the 1920s, the dunes had become a source of pride for local people, and a potential source of tourist dollars for local businesses. Members of the P.E.O. Sisterhood sponsored a bill to Congress asking for national monument status for Great Sand Dunes. Widely supported by local people, the bill was signed into law in 1932 by President Herbert Hoover. Similar support in the late 1990s resulted in the monument’s expansion into a national park and preserve in 2000-2004.[11]

text: Geology[edit]

text: The park contains the tallest sand dunes in North America,[7] rising to a maximum height of 750 feet (229 m)[4] from the floor of the San Luis Valley on the western base of the Sangre de Cristo Range. The dunes cover an area of about 30 sq mi (78 km2) and are estimated to contain over 5 billion cubic meters of sand.[8]

text: Creation of the San Luis Valley began when the Sangre de Cristo Range was uplifted in the rotation of a large tectonic plate. The San Juan Mountains to the west of the valley were created through extended and dramatic volcanic activity. The San Luis Valley encompasses the area between the two mountain ranges and is roughly the size of the state of Connecticut. Sediments from both mountain ranges filled the deep chasm of the valley, along with huge amounts of water from melting glaciers and rain. The presence of larger rocks along Medano Creek at the base of the dunes, elsewhere on the valley floor, and in buried deposits indicates that some of the sediment has been washed down in torrential flash floods.[9]

text: In 2002, geologists discovered lakebed deposits on hills in the southern part of the valley, confirming theories of a huge lake that once covered much of the San Luis Valley floor. The body of water was named Lake Alamosa after the largest town in the valley. Lake Alamosa suddenly receded after its extreme water pressure broke through volcanic deposits in the southern end of the valley. The water then drained through the Rio Grande, likely forming the steep Rio Grande Gorge near Taos, New Mexico. Smaller lakes still covered the valley floor, including two broad lakes in the northeastern side of the valley. Large amounts of sediment from the volcanic San Juan Mountains continued to wash down into these lakes, along with some sand from the Sangre de Cristo Range. Dramatic natural climate change later significantly reduced these lakes, leaving behind the sand sheet. Remnants of these lakes still exist in the form of sabkha wetlands.[9]

text: Sand that was left behind after the lakes receded blew with the predominant southwest winds toward a low curve in the Sangre de Cristo Range. The wind funnels toward three mountain passes—Mosca, Medano, and Music Passes—and the sand accumulates in this natural pocket. The winds blow from the valley floor toward the mountains, but during storms the winds blow back toward the valley. These opposing wind directions cause the dunes to grow vertically. Two mountain streams—Medano and Sand Creeks—also capture sand from the mountain side of the dunefield and carry it around the dunes and back to the valley floor. The creeks then disappear into the sand sheet, and the sand blows back into the dunefield. Barchan and transverse dunes form near these creeks. The combination of opposing winds, a huge supply of sand from the valley floor, and the sand recycling action of the creeks, are all part of the reason that these are the tallest dunes in North America.[9]

text: Sufficient vegetation has grown on the valley floor that there is little sand blowing into the main dunefield from the valley; however, small parabolic dunes continue to originate in the sand sheet and migrate across grasslands, joining the main dunefield. Some of these migrating dunes become covered by grasses and shrubs and stop migrating. The dunes system is fairly stable as the opposing wind directions balance each other out over time. Also, the main dunefield is moist beneath a thin layer of dry surface sand. While the top few inches of sand are blown around during windstorms, the moist sand remains largely in place.[9]

text: Scientists estimate that Lake Alamosa disappeared about 440,000 years ago, but the dunes themselves apparently originate from sand deposits from later, smaller lakes. A relatively new dating process, optically stimulated luminescence (OSL), is still in development. This method takes core samples of sand from deep within a dune, and attempts to measure how long quartz grains have been buried in the dark. If the deepest sand deposits can be accurately dated, the age of the dunes could be determined. Samples of sand from deep in the dunes have returned OSL dates varying between a few hundred years to tens of thousands of years old. The oldest dated deposits found so far would have accumulated in the late Pleistocene epoch, during the middle years of the current ice age's third stage.[9]

text: The dunes contain dark areas which are deposits of magnetite, a mineral that has eroded out of the Sangre de Cristo Range. Magnetite is both attracted to a magnet and can be magnetized to become a magnet itself; it is the most magnetic mineral in nature.[19] Magnetite is an oxide of iron which is heavier than the surrounding particles of sand. When overlying sand is removed by wind, magnetite deposits stay in place and are visible as dark patches in the dunefield.[20]

text: Geography[edit]

text: Great Sand Dunes National Park and Preserve is located in Saguache and Alamosa Counties, Colorado at approximately 37.75° north latitude and 105.5° west longitude. The national park is located in the San Luis Valley while the national preserve is located to the east in an adjacent section of the Sangre de Cristo Range of the Rocky Mountains.[5] Elevations range from 7,515 ft (2,291 m) in the valley west of the dunes, to 13,604 ft (4,146 m) at the summit of Tijeras Peak in the northern part of the preserve.[21][10]

text: The dunes cover an area of about 30 sq mi (78 km2) while the surrounding relatively flat sand sheet which feeds the large dunes is actually the largest component of the entire dunes system, containing about 90% of all the sand in the park.[8] The forested and often snowcapped mountains exceeding 13,000 ft (4,000 m) to the east are the most prominent feature, towering over the high dunes. Other features include snow-fed creeks originating high in the mountains, and several alpine lakes. Two spring-fed creeks in the sand sheet along with a few small lakes in the valley's sabkha section southwest of the dunes create a wetland that nurtures wildlife.[10]

text: The main dunefield measures roughly 4 mi (6.4 km) east-to-west and 6 mi (9.7 km) north-to-south, with an adjacent 6 sq mi (16 km2) area to the northwest called the Star Dune Complex, for a total of about 30 sq mi (78 km2). The park and preserve together are approximately 15 mi (24 km) east-to-west at the widest point, and approximately 15 mi (24 km) north-to-south, also at the widest point.[5] The park encompasses 107,342 acres (167.7 sq mi), while the preserve protects an additional 41,686 acres (65.1 sq mi) for a total of 149,028 acres (232.9 sq mi).[1]

text: The Rio Grande National Forest is located to the north and southeast while the remaining forested slopes directly to the east of the dunes were redesignated the Great Sand Dunes National Preserve. The San Isabel National Forest is located to the east of the preserve just beyond the ridge of the Sangre de Cristo Range. Private property abuts most of the southern boundary of the park. The San Luis Lakes State Wildlife Area lies adjacent to the southwestern corner of the park, while the Rio Grande flows through the valley farther to the southwest. The Baca National Wildlife Refuge lies adjacent to the west, and the slopes of the San Juan Mountains begin at the western edge of the valley. Private property of the Baca Grande subdivision of Crestone lies adjacent to the northwest.[5]

text: The nearest city is Alamosa which is about 30 mi (48 km) away by road to the southwest.[22][23] The nearest towns are Crestone to the north, Mosca and Hooper to the west, Blanca and Fort Garland to the south, and Gardner to the east. Colorado Springs and Denver are located a few hours away by car to the northeast.[23] The major roads through the San Luis Valley are U.S. Route 160 on an east–west alignment passing south of the park, and U.S. Route 285 on a north–south alignment passing west of the park and generally parallel to Colorado State Highway 17, which is the closer of the two north–south roadways.[23]

text: Climate[edit]

text: The Great Sand Dunes are located in the high elevation desert of the San Luis Valley, just west of the Sangre de Cristo Range. The summer high temperatures are atypical for a desert area as the average high temperature is only slightly above 80 °F (27 °C) in the warmest month of July; however, the large spread between high and low temperatures is typical of a high desert climate. Low temperatures during winter nights can be extremely cold, with average low temperatures well below 32 °F (0 °C) and record low temperatures below 0 °F (−18 °C) from November through April.[24] Precipitation is very low on the dunes, averaging just 11.13 inches (283 mm) of rainfall per year.[25] The high evaporation rates on the dunes qualify the area as a desert, even though precipitation exceeds 10 inches (250 mm).

text: Spring can sometimes bring high winds, mainly in the afternoon. Spring conditions vary greatly, from mild and sunny to cold and snowy. March is the snowiest month of the year, though some days are above 50 °F (10 °C). In late spring, when Medano Creek usually has its peak flow, snow or high winds are still possible. In summer, daytime high temperatures average 75–80 °F (24–27 °C); however, sand surface temperatures can soar to 150 °F (66 °C) on sunny afternoons. Summer nights are cool—the park is located 8,200 ft (2,500 m) above sea level—with nighttime temperatures often dropping below 50 °F (10 °C). Afternoon thundershowers are common in July and August with cool winds, heavy rain and lightning. Fall is generally mild, with Indian summer days when temperatures reach 60 °F (16 °C) and higher, but chilly nights below freezing. Occasional fall storms bring icy rain or snow. Cold temperatures well below freezing are typical in winter, although the sunshine is generally abundant and the dry air doesn't feel as cold as more humid areas. The average winter high temperatures are just above freezing even in January, which is the coldest month of the year.[26]

text:
[hide]Climate data for Great Sand Dunes National Park and Preserve (1950–2006)

Month
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Year

Record high °F (°C)
67
(19)
63
(17)
72
(22)
78
(26)
89
(32)
96
(36)
94
(34)
90
(32)
87
(31)
80
(27)
67
(19)
60
(16)
96
(36)

Average high °F (°C)
35.1
(1.7)
39.2
(4)
46.8
(8.2)
56.3
(13.5)
66.2
(19)
76.6
(24.8)
80.8
(27.1)
77.9
(25.5)
71.5
(21.9)
60.5
(15.8)
45.5
(7.5)
36.4
(2.4)
57.7
(14.3)

Daily mean °F (°C)
22.4
(−5.3)
26.5
(−3.1)
33.9
(1.1)
42.1
(5.6)
51.5
(10.8)
60.9
(16.1)
65.6
(18.7)
63.2
(17.3)
56.6
(13.7)
46.1
(7.8)
32.8
(0.4)
23.9
(−4.5)
43.8
(6.6)

Average low °F (°C)
9.8
(−12.3)
13.9
(−10.1)
21.0
(−6.1)
28.0
(−2.2)
36.8
(2.7)
45.2
(7.3)
50.5
(10.3)
48.5
(9.2)
41.7
(5.4)
31.7
(−0.2)
20.1
(−6.6)
11.3
(−11.5)
29.9
(−1.2)

Record low °F (°C)
−25
(−32)
−22
(−30)
−9
(−23)
−6
(−21)
15
(−9)
25
(−4)
31
(−1)
33
(1)
22
(−6)
2
(−17)
−12
(−24)
−19
(−28)
−25
(−32)

Average precipitation inches (mm)
0.44
(11.2)
0.37
(9.4)
0.77
(19.6)
0.89
(22.6)
1.09
(27.7)
0.86
(21.8)
1.79
(45.5)
2.00
(50.8)
1.22
(31)
0.86
(21.8)
0.49
(12.4)
0.36
(9.1)
11.13
(282.7)

Average snowfall inches (cm)
6.8
(17.3)
5.3
(13.5)
8.3
(21.1)
5.7
(14.5)
1.4
(3.6)
0
(0)
0
(0)
0
(0)
0.1
(0.3)
2.6
(6.6)
4.7
(11.9)
5.6
(14.2)
40.5
(102.9)

Source #1: https://www.wrcc.dri.edu/cgi-bin/cliGCStT.pl?cogrea (temperatures) [24]

Source #2: https://wrcc.dri.edu/cgi-bin/cliMAIN.pl?cogrea (precipitation/snowfall) [25]

text: Ecology[edit]

text: The four primary components of the Great Sand Dunes system are the mountain watershed, the dunefield, the sand sheet, and the sabkha. The mountain watershed receives heavy snow and rain which feeds creeks that flow down from alpine tundra and lakes, through subalpine and montane woodlands, and finally around the main dunefield. Sand that has blown from the valley floor is captured in streams and carried back toward the valley. As creeks disappear into the valley floor, the sand is picked up and carried to the dunefield once again. The recycling action of water and wind, along with a 7% moisture content below the dry surface holding the sand together, contributes to the great height of the dunes.[8]

text: The dunefield is composed of reversing dunes, transverse dunes—also called crescentic or barchan dunes—and star dunes. The sand sheet is the largest component of the system, comprising sandy grasslands that extend around three sides of the dunefield. Almost 90% of the sand deposit is found in the sand sheet, while the remainder is found in the dunefield. Small parabolic dunes form in the sand sheet and then migrate into the main dunefield. Nabkha dunes form around vegetation. The sabkha forms where sand is seasonally saturated by rising ground water. When the water evaporates away in late summer, minerals similar to baking soda cement sand grains together into a hard, white crust. Areas of sabkha can be found throughout western portions of the sand sheet, wherever the water table meets the surface. Some wetlands in the sabkha are deeper with plentiful plants and animals, while others are shallow and salty.[8]

text: Flora[edit]

text: There are hundreds of plant species in the park and preserve, adapted for environments as diverse as alpine tundra and warm water wetlands. Trees include aspen, Douglas fir, pinyon pine, ponderosa pine, Rocky Mountain juniper, three-leaf sumac, bristlecone pine, red osier dogwood, and narrow-leaf cottonwood.[27][28]

text: Among the flowering plants are alpine phlox, dwarf clover, alpine forget-me-not, fairy primrose, alpine aven, Indian paintbrush, lousewort, blue-purple penstemon, aspen daisy, western paintbrush, elephantella, snow buttercups, scurfpea, Indian ricegrass, blowout grass, prairie sunflower, Rocky Mountain beeplant, rubber rabbitbrush, speargrass, small-flowered sand verbena, narrowleaf yucca, prickly pear cactus, Rocky Mountain iris, and white water buttercup.[27][28]

text: Inland saltgrass is the primary type of grass around sabkha wetlands in the park.[27]

text: Fauna[edit]

text: Mammals include—from alpine tundra to low elevation grasslands—the pika, yellow-bellied marmot, bighorn sheep, black bear, snowshoe hare, Abert's squirrel, cougar, mule deer, water shrew, beaver, kangaroo rat, badger, pronghorn, and elk. Over 1500 bison are currently ranched within park boundaries on private land owned by The Nature Conservancy which is only open to the public through tours.[29]

text: Over 200 species of birds are found throughout the park. From higher to lower elevations and dependent on season, some of the bird species include the brown-capped rosy finch, white-tailed ptarmigan, red-breasted nuthatch, peregrine falcon, mountain bluebird, northern pygmy owl, dusky grouse, hummingbird (four species), western tanager, burrowing owl, bald eagle, golden eagle, sandhill crane, American avocet, and great blue heron.[30]

text: Various reptiles live in the park, such as the short-horned lizard, fence lizard, many-lined skink, bullsnake, and garter snake.[31]

text: Fish living in the park's streams include the Rio Grande cutthroat trout, Rio Grande sucker (Catostomus plebeius), and fathead minnow.[32]

text: Amphibians include the tiger salamander, chorus frog, northern leopard frog, spadefoot toad, Great Plains toad, and Woodhouse's toad.[33]

text: The park harbors several endemic insects including the Great Sand Dunes tiger beetle, a circus beetle (Eleodes hirtipennis), Werner's (Amblyderus werneri) and Triplehorn's (Amblyderus triplehorni) ant-like flower beetle, as well as undescribed species of clown beetle, noctuid moth, and robber fly. More than a thousand different kinds of arthropods have been found at the Great Sand Dunes.[34]

text: Ecosystems[edit]

text: Alpine tundra is the highest elevation ecosystem at Great Sand Dunes where the conditions are too harsh for trees to survive, but wildflowers, pikas, yellow-bellied marmots, ptarmigans, and bighorn sheep thrive. The tundra begins about 11,700 ft (3,600 m) and continues upward to the highest peaks in the park. At subalpine elevations near the tree line grow krummholz (meaning "crooked wood")—trees which are stunted and twisted due to high winds, snow, ice, short growing seasons, and shallow, poorly developed soils. The transition zone between subalpine forest and alpine tundra is an important refuge during storms for some mammals and birds who primarily live on tundra. Bristlecone and limber pines grow at an extremely slow rate, with small statures that belie their true ages as some are more than a thousand years old.[10]

text: Subalpine forests and meadows capture heavy snow in winter and soaking rains in summer. The highest diversity of Rocky Mountain species of plants and animals are found in this ecosystem. Subalpine forest extends from 9,500 ft (2,900 m) to tree line at 11,700 ft (3,600 m). Montane forests and woodlands are found along the drier foothills at approximately 8,000 ft (2,400 m) to 9,500 ft (2,900 m). Pinyon-juniper and ponderosa pine woodlands are found on open, drier slopes, while cottonwood and aspen trees are in drainages. Cougars hunt mule deer here at night. Owls, dusky grouse, turkeys, and bullsnakes all find habitat in these drier, open woodlands.[10]

text: The riparian zone follows creeks through the subalpine and montane ecosystems at Great Sand Dunes. Cottonwood and aspen trees, red osier dogwood, and alder grow well in this wet environment, in turn providing shade and habitat for black bears, water shrews, and western tanagers. Rio Grande cutthroat trout are found in Medano Creek.[10]

text: While the top few inches of the dunefield are often dry, the dunes are moist year-round due to ongoing precipitation. Moisture content of 7% beneath the surface sand allows species such as Ord's kangaroo rat, Great Sand Dunes tiger beetle, scurfpea, and blowout grass to survive here. Many animals visit the dunes from other habitats, including elk, pronghorn, bison, coyotes, bobcats, and raptors.[10]

text: The sand sheet includes extensive grasslands and shrublands that surround the dunefield on three sides, from 7,500 ft (2,300 m) to 8,200 ft (2,500 m). The sand sheet varies from wet meadows to cool-grass prairie to desert shrubland, depending on proximity to groundwater and soil type. Elk and pronghorn are common, while burrowing owls nest in the ground and other raptors float through the skies searching for mice, kangaroo rats, and short-horned lizards.[10]

text: The sabkha is a wetland region where groundwater rises and falls seasonally, leaving white alkali deposits on the surface. Inland saltgrass is common in this area. Toads can reproduce in sabkha wetlands when they are seasonally filled with sufficient fresh water. Shore birds such as the American avocet hunt tadpoles and insects in the shallow water. Wetlands speckle the San Luis Valley and are important habitat for sandhill cranes, shore birds, amphibians, dragonflies, and freshwater shrimp. Grassland species such as elk also use these waters for drinking. The sabkha and wetlands are at approximately 7,500 ft (2,300 m) in elevation.[10]

text: Features[edit]

text: The park preserves the tallest sand dunes in North America,[7] as well as alpine lakes and tundra, mountain peaks over 13,000 feet (3,962 m) in elevation, mixed conifer forests, grasslands, and wetlands.[35]

text: Medano Creek, which borders the east side of the dunes, never finds a permanent and stable streambed as fresh sand falls in the creek. Small underwater sand ridges that act like dams form and break down, creating surges of water which resemble waves. The surges occur at an average interval of about 20 seconds. In a high-water year, the surges can be as high as 20 in (51 cm). The "surge flow" mainly occurs during the peak flow period from late May to early June in most years.[12]

text: Big Spring Creek is a unique spring-fed creek formed by an unconfined aquifer which creates wetlands that support rare species and plant communities in a generally arid area. The creek was designated a National Natural Landmark in 2012.[36]

text: Recreation[edit]

text: Accessing the dunes requires walking across the wide and shallow Medano Creek. The creek typically flows past the main dunes parking area from late April through late June, with peak flow occurring from late May to early June in most years. In other months, the creek is usually only a few inches deep, if there is any water at all.[12] Hiking is permitted throughout the dunes, with the warning that the sand can get very hot in the summer, up to 150 °F (66 °C).[13] Sand wheelchairs are available at the visitor center.[37] Sandboards and sand sleds can be rented just outside the park entrance or in Alamosa which is the closest city.[14]

text: Mosca Pass Trail is a 7 mi (11 km) roundtrip hike that follows a small creek through aspen and evergreen forests to Mosca Pass—elevation 9,737 ft (2,968 m)[5]—in the Sangre de Cristo Range. American Indians and early settlers used this route for travel between the San Luis Valley and the Wet Mountain Valley to the east. Several trails located in the northeastern section of the park lead to alpine lakes high in the mountains. A trail to Medano Lake and the summit of Mount Herard is located off Medano Pass Road. A trail along Sand Creek leads to the Sand Creek Lakes and Music Pass—elevation 11,380 ft (3,470 m)[5]—with a view of the Upper Sand Creek basin. Spur trails along Sand Creek lead to the four alpine lakes which feed the creek, and to several 13,000 ft (4,000 m) peaks above the basin. The Sand Ramp Trail traverses between the dunefield and the mountains, connecting the park's campground to Medano Pass Road (follow the road up to Medano Lake and Pass), as well as the base of the Sand Creek Trail.[13][5] Most of the park's grasslands, shrublands and wetlands have no established trails but are generally open to hiking. The Nature Conservancy's Medano Ranch property may only be visited on a guided tour. A fence surrounds the property to contain the Conservancy's bison herd and demarcate the boundaries.[38]

text: Medano Pass Road is a 22 mi (35 km) four-wheel drive (4WD) road that begins where the main park road ends.[39] The unpaved road crosses Medano Creek nine times and traverses 4 mi (6.4 km) of deep sand. Only street-licensed 4WD motor vehicles or motorcycles, and bicycles are permitted.[15] Fat tire bikes are the only type of bicycle recommended by the park service due to the deep sandy stretches.[40] The road winds around the eastern side of the dunefield, up through a forested mountain canyon inside the National Preserve, and then over Medano Pass—elevation 9,982 ft (3,043 m)[5]—at the 11.2 mi (18.0 km) mark. The road then continues down into the Wet Mountain Valley and connects with Colorado State Highway 69. Travellers are advised that hunting is permitted in the National Preserve during the months of autumn.[15]

text: Most of the national park and the entire national preserve are open to horseback riding and pack animals. Prohibited zones include all developed areas—such as the Pinyon Flats campground, picnic areas, and the visitor center—all paved roadways and many of the hiking trails, along with the dunes area from the parking lot to as far as the High Dune, which is for pedestrian use only. All national park horse camping areas are in the wilderness in designated backcountry campsites or other wilderness areas at least 0.25 mi (0.4 km) from roads or trails. Camping is permitted anywhere in the national preserve and at designated sites along the Medano Pass Road, as long as minimum impact guidelines are followed. Permitted pack animals in the national park and the preserve include horses, mules, burros, donkeys, alpacas, and llamas. Overnight guests at the Zapata Ranch may take guided trips into the park; Zapata Partners is the only NPS-licensed provider of horseback riding in the Great Sand Dunes.[41][42]

text: Unlike all other national parks in the contiguous United States, Great Sand Dunes National Park is located directly adjacent to a national preserve. The preserve is also managed by the National Park Service and seasonal hunting is permitted there.[16] Sport hunting has regulations which include not pursuing a wounded animal if it leaves the preserve and enters the national park. Mountain lion hunting with dogs is also allowed in the preserve, but unless the dogs have spotted the lion and are pursuing it, they are required to be leashed.[43] Other game species include turkey, bear, bighorn sheep, elk and mule deer.[44]

text: Designations[edit]

text: The dunes and surrounding area were designated a national monument in 1932 after a bill—sponsored by the P.E.O. Sisterhood and widely supported by local residents—was signed into law by President Herbert Hoover. Similar support in the late 1990s resulted in the monument’s redesignation as Great Sand Dunes National Park and Preserve in 2000-2004.[11] The original boundaries protected an area of 35,528 acres (55.5 sq mi).[6]

text: In 1976, the U.S. Congress designated the Great Sand Dunes Wilderness—a wilderness area encompassing 32,643 acres (51 sq mi) within the monument. This wilderness is the only one in the U.S. that protects a saltbush-greasewood ecosystem and includes the entire dunefield as well as much of the area west of the dunes.[45][46] Congress also designated the Sangre de Cristo Wilderness in 1993, which contains a total of 219,776 acres (343.4 sq mi) of mountainous terrain.[47] Most of the Sangre de Cristo Wilderness is managed by the U.S. Forest Service while the National Park Service manages the area that has since been designated a national preserve.[48] Mechanized transport and motorized equipment or vehicles are not permitted in wilderness areas, while ATVs are not permitted anywhere in the national park and preserve.[47] The restrictions of a wilderness designation protect native wildlife such as the endemic Great Sand Dunes tiger beetle from potential extinction caused by human activities.[49] Both of the wilderness area designations exclude the existing road corridors that pass through them, specifically the paved park road and the unpaved Medano Pass Road.[46]

text: In 1999, the Nature Conservancy purchased surrounding state-owned land.[50] The land is within the Medano–Zapata Ranch, located to the west and south.[51] Some of the ranch land is located within the current national park boundary in its southwestern corner,[5] and includes a fenced area that contains a bison herd within 44,000 acres (68.8 sq mi)[50]—an area that can only be visited on a guided tour.[52][53] The objective of the Nature Conservancy, as well as the federal and state governments, is to combine conservation and sustainable use of the ecosystem, in a manner similar to the protected area mosaic recommended in the early 1980s for parts of the Yukon in Canada.[51]

text: The eventual redesignation as Great Sand Dunes National Park and Preserve was authorized on November 22, 2000 when President Bill Clinton signed the Congressionally-approved Great Sand Dunes National Park and Preserve Act. The act directed the Secretary of the Interior to "establish the Great Sand Dunes National Park when sufficient land having sufficient diversity of resources has been acquired to warrant its designation."[54] The new designation as a national park and preserve would not be made official until 2004 after sufficient land had been acquired.[55][56]

text: In 2002, the Nature Conservancy purchased the Baca Ranch—an area of 97,000 acres (151.6 sq mi)—for $31.28 million. Financing was provided by the Department of the Interior, the Colorado State Land Board and private donors. The Baca Ranch had property located in the valley and the adjacent mountains, ranging in elevation from 7,500 ft (2,286 m) west of the dunes to the 14,165 ft (4,317 m) summit of Kit Carson Peak. The purchase approximately tripled the size of the monument. The ranch was split into three sections: the Sangre de Cristos section east of Crestone became part of the Rio Grande National Forest; the section west of the dunes was designated the Baca National Wildlife Refuge and managed by the Fish and Wildlife Service; the section east of the dunes was transferred first to the Rio Grande National Forest and later redesignated a national preserve in 2004 managed by the National Park Service. The national preserve remains open to regulated seasonal hunting, as it was when designated national forest land, but is protected from logging and mining activities which are generally permitted in national forests.[57]

text: The boundaries of the Great Sand Dunes National Park and Preserve were established by an act of Congress on September 24, 2004.[2]

text: In 2016, the federal government began negotiations toward purchasing 12,518 acres (19.6 sq mi) of the Medano–Zapata Ranch from the Nature Conservancy. The plan is to complete the park, making it fully accessible to the public, by acquiring the final piece of privately-held land located within the current park boundaries. The land includes the area presently occupied by the bison herd, as well as adjacent meadows and wetland areas. The purchase is expected to be completed by 2018.[56]


document_title: India at the Olympics

question_text: who won first gold medal for india in olympics

root

text: India at the Olympics

text: History[edit]

text: Early history[edit]

text: India sent its first athlete to the Olympics for the 1900 games, but an Indian national team did not compete at the Olympics until 1920. Ahead of the 1920 Olympics, Sir Dorab Tata and Governor of Bombay George Lloyd helped India secure representation at the International Olympic Council, enabling it to participate in the Olympic Games (see India at the 1920 Olympic Games). India then sent a team to the 1920 Olympics, comprising four athletes, two wrestlers, and managers Sohrab Bhoot and A H A Fyzee. The Indian Olympic movement was then established during the 1920s: some founders of this movement were Dorab Tata, A.G. Noehren (Madras College of Physical Education), H.C. Buck (Madras College of Physical Education), Moinul Haq (Bihar sports associations), S. Bhoot (Bombay Olympic Association), A.S. Bhagwat (Deccan Gymkhana), and G.D. Sondhi (Punjab Olympic Association); Lt.Col H.L.O. Garrett (from the Government College Lahore and Punjab Olympic Association) and Sagnik Poddar (of St.Stephen's School) helped organise some early national games; and prominent patrons included Maharajas and royal princes Bhupinder Singh of Patiala, Ranji of Nawanagar, the Maharaja of Kapurthala, and the Maharaja of Burdwan.

tag: p

text: In 1923, a provisional All India Olympic Committee was formed, and in Feb 1924 the All India Olympic Games (that later became the National Games of India) were held to select a team for the Paris Olympics. The Indian delegation at the Paris Olympics comprised seven athletes, seven tennis players and team manager Harry Buck.

text: In 1927, the provisional Indian Olympic Committee formally became the Indian Olympic Association (IOA)-its main tasks were to promote the development of sports in India, choose host cities for the national games, and send teams-selected from the national games-to the Olympics. Thus, at the 1928 national games, it selected seven athletes to represent India at the next Olympics, with G. D. Sondhi as manager for the Olympic team. By this time, the Indian Hockey Federation (IHF) had also been established and it sent a hockey team to the Olympics. The national hockey team and additional sportspersons were similarly sent to the Olympic Games in 1932 (four athletes and one swimmer) and 1936 (four athletes, three wrestlers, one Burmese weight-lifter), along with three officials headed by team manager Sondhi.

text: From 1948 onward, because of the Indian Olympic Association's wider outreach, India began sending delegations of over 50 sportspersons representing several sports – each selected by its sports federation – to the Olympics. The delegation was headed by a chef-de-mission.

text: Thus, India’s Olympic delegation in the early Olympic Games was as follows:

text:
1900: One athlete
1920: 6 competitors (four athletes, two wrestlers) and managers Bhoot and Fyzee
1924: 14 competitors (seven athletes, seven tennis players) and manager Harry Crowe Buck
1928: 21 competitors (seven athletes and a hockey team of 14) and manager G D Sondhi
1932: 20 competitors (four athletes, one swimmer, and a hockey team of 15) and three officials headed by manager G D Sondhi
1936: 27 competitors (four athletes, three wrestlers, one Burmese weight-lifter, and a hockey team of 19) and three officials including manager G D Sondhi
1948: 79 competitors and a few officials headed by chef-de-mission Moin ul Haq
1952: 64 competitors and some officials headed by chef-de-mission Moin ul Haq

tag: ul

text: Recent history[edit]

text: At the 2008 Beijing Olympics, Abhinav Bindra won gold in the Men's 10 metre air rifle event becoming the first Indian to win an individual gold medal at the Olympic Games. Vijender Singh got the country's first medal in boxing with his bronze medal in Middleweight category.

text: The 2012 Summer Olympics saw an 83-member Indian contingent participating in the games and setting a new best for the country with a total of six medals. Wrestler Sushil Kumar became the first Indian with multiple individual Olympic medals (bronze at the 2008 Beijing Olympics and silver at the 2012 Summer Olympics) since Norman Pritchard in 1900. Saina Nehwal won bronze medal in badminton in Women's singles getting the country's first Olympic medal in badminton. Pugilist Mary Kom became the first Indian woman to win a medal in boxing with her bronze medal finish in Women's flyweight category.

text: At the 2016 Summer Olympics, a record number of 118 athletes competed. Sakshi Malik became the first Indian woman wrestler to win an Olympic medal with her bronze medal finish in Women's freestyle 58 kg category. Shuttler P. V. Sindhu became the first Indian woman to win a silver medal in Olympics and also the youngest Indian Olympic medallist.

text: List of competitors[edit]

text: This list provides a comparative compendium of all the participants/competitors of India in the summer Olympic games.

text:
Games
Sports
Men
Women
Total
Change
01 ! Gold
02 ! Silver
03 ! Bronze
Total
Change

1900
1
1
0
1
NA
0
2
0
2
NA

1920
2
6
0
6
+5
0
0
0
0
−2

1924
2
13
2
15
+8
0
0
0
0
0

1928
2
21
0
21
+7
1
0
0
1
+1

1932
3
30
0
30
+9
1
0
0
1
0

1936
3–4
27
0
27
−3
1
0
0
1
0

1948
10
79
0
79
+52
1
0
0
1
0

1952
11
60
4
64
−15
1
0
1
2
+1

1956
8
58
1
59
−5
1
0
0
1
−1

1960
6
45
0
45
−14
0
1
0
1
0

1964
8
52
1
53
+8
1
0
0
1
0

1968
5
25
0
25
−28
0
0
1
1
0

1972
7
40
1
41
+16
0
0
1
1
0

1976
2
20
0
20
−21
0
0
0
0
−1

1980
1
58
18
76
+56
1
0
0
1
+1

1984

48
−28
0
0
0
0
−1

1988
7

46
−2
0
0
0
0
0

1992
5

53
+7
0
0
0
0
0

1996
13
44
4
49
−4
0
0
1
1
+1

2000
7

65
+16
0
0
1
1
0

2004
14
48
25
73
+8
0
1
0
1
0

2008
12
31
25
56
−17
1
0
2
3
+2

2012
13
60
23
83
+27
0
2
4
6
+3

2016
15
66
54
118
+35
0
1
1
2
−4

tag: table

text: This list provides a comparative compendium of all the participants/competitors of India in the winter Olympic games.

text:
Games
Sports
Men
Women
Total
Change
01 ! Gold
02 ! Silver
03 ! Bronze
Total
Change

1964
1
1
0
1
NA
0
0
0
0
NA

1968
1
1
0
1
0
0
0
0
0
0

1988
1
2
1
3
+2
0
0
0
0
0

1992
1
2
0
2
−1
0
0
0
0
0

1998
1
1
0
1
−1
0
0
0
0
0

2002
1
1
0
1
0
0
0
0
0
0

2006
3
3
1
4
+3
0
0
0
0
0

2010
3
3
0
3
−1
0
0
0
0
0

2014
3
3
0
3
0
0
0
0
0
0

text: Medal tables[edit]

text: Medals by Summer Games[edit]

text:
Games
01 ! Gold
02 ! Silver
03 ! Bronze
Total
Rank

 1896 Athens
did not participate

 1900 Paris
0
2
0
2[1]
17

 1904 St. Louis
did not participate

 1908 London
did not participate

 1912 Stockholm
did not participate

 1920 Antwerp
0
0
0
0
-

 1924 Paris
0
0
0
0
-

 1928 Amsterdam
1
0
0
1[2]
23

 1932 Los Angeles
1
0
0
1[3]
19

 1936 Berlin
1
0
0
1[4]
20

 1948 London
1
0
0
1[5]
22

 1952 Helsinki
1
0
1
2[5]
26

 1956 Melbourne
1
0
0
1[5]
24

 1960 Rome
0
1
0
1[6]
32

 1964 Tokyo
1
0
0
1[7]
24

 1968 Mexico City
0
0
1
1[8]
42

 1972 Munich
0
0
1
1[9]
43

 1976 Montreal
0
0
0
0
-

 1980 Moscow
1
0
0
1[10]
23

 1984 Los Angeles
0
0
0
0
-

 1988 Seoul
0
0
0
0
-

 1992 Barcelona
0
0
0
0
-

 1996 Atlanta
0
0
1
1[11]
71

 2000 Sydney
0
0
1
1[12]
71

 2004 Athens
0
1
0
1[13]
65

 2008 Beijing
1
0
2
3[13]
50

 2012 London
0
2
4
6[13]
55

 2016 Rio de Janeiro
0
1[14]
1[15]
2[16]
67

Total
9
7
12
28

text: Medals by sport[edit]

text:
Sport
01 ! Gold
02 ! Silver
03 ! Bronze
Total
Rank

 Field hockey
8
1
2
11
1

 Shooting
1
2
1
4
34

 Athletics
0
2
0
2
71

 Wrestling
0
1
4
5
43

 Badminton
0
1
1
2
9

 Boxing
0
0
2
2
64

 Tennis
0
0
1
1
30

 Weightlifting
0
0
1
1

56

Total
9
7
12
28

text: List of medalists[edit]

text:
Medal
Name/Team
Games
Sport
Event

02 ! Silver
Pritchard, NormanNorman Pritchard[1][17]
 1900 Paris
Athletics
Men's 200 metres

02 ! Silver
Pritchard, NormanNorman Pritchard[1][17]
 1900 Paris
Athletics
Men's 200 metre hurdles

01 ! Gold
National team[2]
 1928 Amsterdam
Field hockey
Men's competition

01 ! Gold
National team[3]
 1932 Los Angeles
Field hockey
Men's competition

01 ! Gold
National team[4]
 1936 Berlin
Field hockey
Men's competition

01 ! Gold
National team[5]
 1948 London
Field hockey
Men's competition

01 ! Gold
National team[5]
 1952 Helsinki
Field hockey
Men's competition

03 ! Bronze
Jadhav, Khashaba DadasahebKhashaba Dadasaheb Jadhav[5]
 1952 Helsinki
Wrestling
Men's freestyle bantamweight

01 ! Gold
National team[5]
 1956 Melbourne
Field hockey
Men's competition

02 ! Silver
National team[6]
 1960 Rome
Field hockey
Men's competition

01 ! Gold
National team[7]
 1964 Tokyo
Field hockey
Men's competition

03 ! Bronze
National team[8]
 1968 Mexico City
Field hockey
Men's competition

03 ! Bronze
National team[9]
 1972 Munich
Field hockey
Men's competition

01 ! Gold
National team[10]
 1980 Moscow
Field hockey
Men's competition

03 ! Bronze
Paes, LeanderLeander Paes[11]
 1996 Atlanta
Tennis
Men's singles

03 ! Bronze
Malleswari, KarnamKarnam Malleswari[12]
 2000 Sydney
Weightlifting
Women's 69 kg

02 ! Silver
Rathore, Rajyavardhan SinghRajyavardhan Singh Rathore[13]
 2004 Athens
Shooting
Men's double trap

01 ! Gold
Bindra, AbhinavAbhinav Bindra[13]
 2008 Beijing
Shooting
Men's 10 m Air Rifle

03 ! Bronze
Singh, VijenderVijender Singh[13]
 2008 Beijing
Boxing
Middleweight

03 ! Bronze
Kumar, SushilSushil Kumar[13]
 2008 Beijing
Wrestling
Men's freestyle 66 kg

02 ! Silver
Vijay Kumar[13]
 2012 London
Shooting
Men's 25 Rapid Fire Pistol

02 ! Silver
Kumar, SushilSushil Kumar[13]
 2012 London
Wrestling
Men's freestyle 66 kg

03 ! Bronze
Saina Nehwal[13]
 2012 London
Badminton
Women's singles

03 ! Bronze
Mary Kom[13]
 2012 London
 Boxing
Women's flyweight

03 ! Bronze
Narang, GaganGagan Narang[13]
 2012 London
Shooting
Men's 10m Air Rifle

03 ! Bronze
Yogeshwar Dutt[13]
 2012 London
Wrestling
Men's freestyle 60 kg

02 ! Silver
P. V. Sindhu[14]
 2016 Rio de Janeiro
Badminton
Women's singles

03 ! Bronze
Sakshi Malik[15]
 2016 Rio de Janeiro
Wrestling
Women's freestyle 58 kg


document_title: Vertical pressure variation

question_text: the difference in pressure between the top and bottom of a column of gas is calculated as

text: Vertical pressure variation

text: Basic formula[edit]

text: A relatively simple version [1] of the vertical fluid pressure variation is simply that the pressure difference between two elevations is the product of elevation change, gravity, and density. The equation is as follows:

text: where

text: The delta symbol indicates a change in a given variable. Since g is negative, an increase in height will correspond to a decrease in pressure, which fits with the previously mentioned reasoning about the weight of a column of fluid.

text: When density and gravity are approximately constant (that is, for relatively small changes in height), simply multiplying height difference, gravity, and density will yield a good approximation of pressure difference. Where different fluids are layered on top of one another, the total pressure difference would be obtained by adding the two pressure differences; the first being from point 1 to the boundary, the second being from the boundary to point 2; which would just involve substituting the ρ and Δh values for each fluid and taking the sum of the results. If the density of the fluid varies with height, mathematical integration would be required.

text: Whether or not density and gravity can be reasonably approximated as constant depends on the level of accuracy needed, but also on the length scale of height difference, as gravity and density also decrease with higher elevation. For density in particular, the fluid in question is also relevant; seawater, for example, is considered an incompressible fluid; its density can vary with height, but much less significantly than that of air.  Thus water's density can be more reasonably approximated as constant than that of air, and given the same height difference, the pressure differences in water are approximately equal at any height.

text: Hydrostatic paradox[edit]

text: Wikimedia Commons has media related to Hydrostatic paradox.

text: The barometric formula depends only on the height of the fluid chamber, and not on its width or length.  Given a large enough height, any pressure may be attained. This feature of hydrostatics has been called the hydrostatic paradox. As expressed by W. H. Besant,[2]

text: The Dutch scientist Simon Stevin was the first to explain the paradox mathematically.[3] In 1916 Richard Glazebrook mentioned the hydrostatic paradox as he described an arrangement he attributed to Pascal: a heavy weight W rests on a board with area A resting on a fluid bladder connected to a vertical tube with cross-sectional area α. Pouring water of weight w down the tube will eventually raise the heavy weight. Balance of forces leads to the equation

text: Glazebrook says, "By making the area of the board considerable and that of the tube small, a large weight W can be supported by a small weight w of water. This fact is sometimes described as the hydrostatic paradox."[4]

text: Demonstrations of the hydrostatic paradox are used in teaching the phenomenon.[5][6]

text: In the context of Earth's atmosphere[edit]

text: If one is to analyze the vertical pressure variation of the Atmosphere of Earth, the length scale is very significant (troposphere alone being several kilometres tall; thermosphere being several hundred kilometres) and the involved fluid (air) is compressible. Gravity can still be reasonably approximated as constant, because length scales on the order of kilometres are still small in comparison to Earth's radius, which is on average about 6371 km,[7] and gravity is a function of distance from Earth's core.[8]

text: Density, on the other hand, varies more significantly with height. It follows from the ideal gas law that

text: where

text: Put more simply, air density depends on air pressure. Given that air pressure also depends on air density, it would be easy to get the impression that this was circular definition, but it is simply interdependency of different variables. This then yields a more accurate formula, of the form

text: where

text: Therefore, instead of pressure being a linear function of height as one might expect from the more simple formula given in the "basic formula" section, it is more accurately represented as an exponential function of height.

text: Note that even that is a simplification, as temperature also varies with height. However, the temperature variation within the lower layers (troposphere, stratosphere) is only in the dozens of degrees, as opposed to difference between either and absolute zero, which is in the hundreds, so it is a reasonably small difference. For smaller height differences, including those from top to bottom of even the tallest of buildings, (like the CN tower) or for mountains of comparable size, the temperature variation will easily be within the single-digits. (See also lapse rate.)

text: An alternative derivation, shown by the Portland State Aerospace Society,[9] is used to give height as a function of pressure instead. This may seem counter-intuitive, as pressure results from height rather than vice versa, but such a formula can be useful in finding height based on pressure difference when one knows the latter and not the former. Different formulas are presented for different kinds of approximations; for comparison with the previous formula, the first referenced from the article will be the one applying the same constant-temperature approximation; in which case:

text: where (with values used in the article)

text: A more general formula derived in the same article accounts for a linear change in temperature as a function of height (lapse rate), and reduces to above when the temperature is constant:

text: where

text: and the other quantities are the same as those above.  This is the recommended formula to use.


document_title: Jute cultivation

question_text: when is jute plant cut to obtain fibre

question_tokens: when is jute plant cut to obtain fibre

text: Jute cultivation

text: Cultivation[edit]

text: This section does not cite any sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. (September 2016) (Learn how and when to remove this template message)

text:
To grow jute, farmers  scatter the seeds on cultivated soil. When the plants are about 15–20 cm tall, they are thinned out. About four months after planting, harvesting begins. The plants are usually harvested after they flower, before the flowers go to seed. The stalks are cut off close to the ground. The stalks are tied into bundles and soaked in water  for about 20 days. This process softens the tissues and breaks the hard pectin bond between the bast and Jute hurd (inner woody fiber stick) and the process permits the fibres to be separated. The fibres are then stripped from the stalks in long strands and washed in clear, running water. Then they are hung up or spread on thatched roofs to dry. After 2–3 days of drying, the fibres are tied into bundles.
The suitable climate for growing jute is a warm and wet climate, which is offered by the monsoon climate during the fall season, immediately followed by summer. Temperatures ranging from 25-30 °C and relative humidity of 70%–90% are favorable for successful cultivation. Jute requires 160-200 cm of rainfall weekly with extra needed during the sowing period. River basins or alluvial or loamy soils are best for jute cultivation.Jute cultivation in red soils may require high dose of manure and PH range between 4.8-5.8 is best for its cultivation.
Plain land or gentle slope or low land is ideal for jute cultivation.Since the jute seeds are small in size ,land should be prepared to fine tilth.Couple of ploughing will make the soil to fine tilth.

text: Retting[edit]

text: Retting is the process of extracting fibers  from the long lasting life stem or bast of the bast fiber plants. The available retting processes are: mechanical retting (hammering), chemical retting (boiling & applying chemicals), steam/vapor/dew retting, and water or microbial retting. Among them, the water or microbial retting is a century old but the most popular process in extracting fine bast fibers. However, selection of these retting processes depends on the availability of water and the cost of retting process.

text: To extract fine fibers from jute plant, a small stalk is harvested for pre-retting. Usually, this small stalk is brought before 2 weeks of harvesting time. If the fiber can easily be removed from the Jute hurd or core, then the crop is ready for harvesting.

text: After harvesting, the jute stalks are tied into bundles and submerged in soft running water. The stalk stays submerged in water for 20 days. However, the retting process may require less time if the quality of the jute is better. In most cases, the fiber extraction process of bast fibers in water retting is done by the farmers while standing under water.

text: When the jute stalk is well retted, the stalk is grabbed in bundles and hit with a long wooden hammer to make the fiber loose from the jute hurd or core. After loosing the fiber, the fiber is washed with water and squeezed for dehydration. The extracted fibers is further washed with fresh water and allowed to dry on bamboo poles. Finally, they are tied into small bundles to be sold into the primary market.

text: Major producers[edit]

text: The Ganges delta contributes more than 80% of the jute production in the world. The Ganges delta can be sub-divided into the following geo-graphical regions in terms of jute cultivation:

text:
Jat Area (Brahmaputra Alluvium): This comprises part of the districts of Dhaka, Mymensingh, Tangail, and Comilla of Bangladesh. The area annually receives fresh deposit of silts carried down by the flood water. Soils are acidic in, the texture varies from sand loam to clay loam. According to commercial quality, the best quality Jute, the Jat type, grows in this area.
District Area (Ganges Alluvium): This comprises part of the districts of Kushtia, Jessore, Khulna, Rajshahi, Pabna, and Dhaka of Bangladesh and major portion of West Bengal of India. This area has soil of slight alkaline clay loam to light loam in gray to dark gray color. The type of Jute grown in this area is known as District Jute, which is next to Jat Jute in order of quality. The jute fibre grown in this region is further divided into two major varieties, such as: Hard District Jute and Soft District Jute.
Northern Area (Teesta Silt): This comprises part of Dinajpur, Rangpur districts, East Bogra, and Sirajganj of Bangladesh and some parts of North Bihar Purnea  and West Bengal of India. The region has sandy soil with low moisture retention capacity. Soil retention is slightly acidic. Northern type of Jute is inferior quality of the three commercial types.

text: Strengths of major jute producing countries[edit]

text: India, China, and Bangladesh are the three major producers in the cultivation or production of jute fiber.

text:
India has taken advantage of recent improvements in the cultivation of jute to become the largest producer or cultivator of jute in the world. Using advanced production techniques, India also has dominance over the worldwide jute products market. Due to national law to use jute as packaging materials, India is the largest consumer of jute in the world.
Bangladesh is currently the second largest producer of jute fiber, now over taken by India. The Jat Area, popular for highest quality of jute fiber is located in Bangladesh. Therefore, Bangladesh is able to supply the highest quality of jute fiber in the world. However, Bangladesh falls behind its other competitors in applying recent technological advancements. In terms of world export of jute fiber, Bangladesh's share is more than 70%, which makes Bangladesh the largest exporter of jute fiber in the world.
China is the third largest in terms of jute cultivation. Due to China's huge population, the Chinese are not emphasizing the cultivation of jute, as it competes with other necessary crops.  Due to modern effective agriculture, they have the highest yield of jute fiber in the world.

text: History[edit]

text: For centuries, jute has been an integral part of the culture of East Bengal and some parts of West Bengal, precisely in the southwest of Bangladesh. Since the seventeenth century, the British started trading in jute. During the reign of the British Empire jute was also used in the military. British jute barons grew rich processing jute and selling manufactured products made from jute. Dundee Jute Barons and the British East India Company set up many jute mills in Bengal and by 1895 jute industries in Bengal overtook the Scottish jute trade. Many Scots emigrated to Bengal to set up jute factories. More than a billion jute sandbags were exported from Bengal to the trenches during World War I and also exported to the southern United States region to bag cotton. It was used in the fishing, construction, art and the arms industry. Initially, due to its texture, it could only be processed by hand until it was discovered in Dundee that by treating it with whale oil, it could be treated by machine.[1]