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Colorado River Delta
The Colorado River Delta is the region where the Colorado River once flowed into the Gulf of California (also known as the Sea of Cortez) in eastern Mexicali Municipality in the north of the state of Baja California, in northwestern Mexico. The delta is part of a larger geologic region called the Salton Trough. Historically, the interaction of the river's flow and the ocean's tide created a dynamic environment, supporting freshwater, brackish, and saltwater species. Within the delta region, the river split into multiple braided channels and formed a complex estuary and terrestrial ecosystems. The use of water upstream and the accompanying reduction of freshwater flow has resulted in the loss of most of the wetlands of the area, as well as drastic changes to the aquatic ecosystems - an ecosystem collapse. Natural history Until the early 20th century, the Colorado River ran free from its headwaters in the Rocky Mountains of Colorado southwest into Mexico, where it flowed int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
River Delta
A river delta is a landform, archetypically triangular, created by the deposition of the sediments that are carried by the waters of a river, where the river merges with a body of slow-moving water or with a body of stagnant water. The creation of a river delta occurs at the '' river mouth'', where the river merges into an ocean, a sea, or an estuary, into a lake, a reservoir, or (more rarely) into another river that cannot carry away the sediment supplied by the feeding river. Etymologically, the term ''river delta'' derives from the triangular shape (Δ) of the uppercase Greek letter delta. In hydrology, the dimensions of a river delta are determined by the balance between the watershed processes that supply sediment and the watershed processes that redistribute, sequester, and export the supplied sediment into the receiving basin. River deltas are important in human civilization, as they are major agricultural production centers and population centers. They can provide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Headwaters
The headwater of a river or stream is the geographical point of its beginning, specifically where surface runoff water begins to accumulate into a flowing channel of water. A river or stream into which one or many tributary rivers or streams flows has many headwaters, these being all of the individual headwaters of its tributaries. Each headwater is one of the river or stream's sources, as it is the place where surface runoffs from rainwater, meltwater, or spring water begin accumulating into a more substantial and consistent flow that becomes a first-order tributary of that river or stream. The tributary with the longest channel of all the tributaries to a river or stream, such length measured from that tributary's headwater to its mouth where it discharges into the river or stream, is the main stem of the river or stream in question. Definition The United States Geological Survey (USGS) states that a river's "length may be considered to be the distance from the mouth to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beaver
Beavers (genus ''Castor'') are large, semiaquatic rodents of the Northern Hemisphere. There are two existing species: the North American beaver (''Castor canadensis'') and the Eurasian beaver (''C. fiber''). Beavers are the second-largest living rodents, after capybaras, weighing up to . They have stout bodies with large heads, long chisel-like incisors, brown or gray fur, hand-like front feet, webbed back feet, and tails that are flat and scaly. The two species differ in skull and tail shape and fur color. Beavers can be found in a number of freshwater habitats, such as rivers, streams, lakes and ponds. They are herbivorous, consuming tree bark, aquatic plants, grasses and sedges. Beavers build dams and lodges using tree branches, vegetation, rocks and mud; they chew down trees for building material. Dams restrict water flow, forming ponds, and lodges (usually built in ponds) serve as shelters. Their infrastructure creates wetlands used by many other species, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jaguar
The jaguar (''Panthera onca'') is a large felidae, cat species and the only extant taxon, living member of the genus ''Panthera'' that is native to the Americas. With a body length of up to and a weight of up to , it is the biggest cat species in the Americas and the List of largest cats, third largest in the world. Its distinctively marked Animal coat, coat features pale yellow to tan colored fur covered by spots that transition to Rosette (zoology), rosettes on the sides, although a melanistic black coat appears in some individuals. The jaguar's powerful bite allows it to pierce the Turtle shell#Carapace, carapaces of turtles and tortoises, and to employ an unusual killing method: it bites directly through the skull of mammalian prey between the ears to deliver a fatal blow to the brain. The modern jaguar's ancestors probably entered the Americas from Eurasia during the Early Pleistocene via the land bridge that once spanned the Bering Strait. Today, the jaguar's range ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sonoran Desert
The Sonoran Desert () is a hot desert and ecoregion in North America that covers the northwestern Mexican states of Sonora, Baja California, and Baja California Sur, as well as part of the Southwestern United States (in Arizona and California). It is the hottest desert in Mexico. It has an area of . In phytogeography, the Sonoran Desert is within the Sonoran floristic province of the Madrean region of southwestern North America, part of the Holarctic realm of the northern Western Hemisphere. The desert contains a variety of unique endemic plants and animals, notably, the saguaro (''Carnegiea gigantea'') and organ pipe cactus (''Stenocereus thurberi''). The Sonoran Desert is clearly distinct from nearby deserts (e.g., the Great Basin, Mojave, and Chihuahuan deserts) because it provides subtropical warmth in winter and two seasons of rainfall (in contrast, for example, to the Mojave's dry summers and cold winters). This creates an extreme contrast between aridity and moistur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spawn (biology)
Spawn is the eggs and sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of freely releasing eggs and sperm into a body of water (fresh or marine); the physical act is known as spawning. The vast majority of aquatic and amphibious animals reproduce through spawning. These include the following groups: * Bony fishes * Crustaceans (such as crabs, shrimps, etc.) *Mollusks (such as oysters, octopus, squid) *Echinoderms (such as sea urchins, sea stars, sea cucumbers, etc.) * Amphibians (such as frogs, toads, salamanders, newts) * Aquatic insects (such as dragonflies, mayflies, mosquitoes) *Coral, which are living colonies of tiny, aquatic organisms—not plants, as they are sometimes perceived to be. Corals, while appearing sedentary or botanical by nature, actually spawn by releasing clouds of sperm and egg cells into the water column, where the two mix. As a general rule, aquatic or semiaquatic reptiles, birds, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tide
Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon (and to a much lesser extent, the Sun) and are also caused by the Earth and Moon orbiting one another. Tide tables can be used for any given locale to find the predicted times and amplitude (or " tidal range"). The predictions are influenced by many factors including the alignment of the Sun and Moon, the phase and amplitude of the tide (pattern of tides in the deep ocean), the amphidromic systems of the oceans, and the shape of the coastline and near-shore bathymetry (see '' Timing''). They are however only predictions, the actual time and height of the tide is affected by wind and atmospheric pressure. Many shorelines experience semi-diurnal tides—two nearly equal high and low tides each day. Other locations have a diurnal tide—one high and low tide each day. A "mixed tide"—two uneven magnitude tides a day—is a third regular category. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Riparian
A riparian zone or riparian area is the interface between land and a river or stream. In some regions, the terms riparian woodland, riparian forest, riparian buffer zone, riparian corridor, and riparian strip are used to characterize a riparian zone. The word ''riparian'' is derived from Latin '' ripa'', meaning " river bank". Riparian is also the proper nomenclature for one of the terrestrial biomes of the Earth. Plant habitats and communities along the river margins and banks are called riparian vegetation, characterized by hydrophilic plants. Riparian zones are important in ecology, environmental resource management, and civil engineering because of their role in soil conservation, their habitat biodiversity, and the influence they have on terrestrial and semiaquatic fauna as well as aquatic ecosystems, including grasslands, woodlands, wetlands, and even non-vegetative areas. Riparian zones may be natural or engineered for soil stabilization or restoration. These zon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estuaries
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environments and are an example of an ecotone. Estuaries are subject both to marine influences such as tides, waves, and the influx of saline water, and to fluvial influences such as flows of freshwater and sediment. The mixing of seawater and freshwater provides high levels of nutrients both in the water column and in sediment, making estuaries among the most productive natural habitats in the world. Most existing estuaries formed during the Holocene epoch with the flooding of river-eroded or glacially scoured valleys when the sea level began to rise about 10,000–12,000 years ago. Estuaries are typically classified according to their geomorphology, geomorphological features or to water-circulation patterns. They can have many different names, s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desert
A desert is a landscape where little precipitation occurs and, consequently, living conditions create unique biomes and ecosystems. The lack of vegetation exposes the unprotected surface of the ground to denudation. About one-third of the land surface of the Earth is arid or Semi-arid climate, semi-arid. This includes much of the Polar regions of Earth, polar regions, where little precipitation occurs, and which are sometimes called polar deserts or "cold deserts". Deserts can be classified by the amount of precipitation that falls, by the temperature that prevails, by the causes of desertification or by their geographical location. Deserts are formed by weathering processes as large variations in temperature between day and night strain the Rock (geology), 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 frag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imperial Valley
The Imperial Valley ( or ''Valle Imperial'') of Southern California lies in Imperial and Riverside counties, with an urban area centered on the city of El Centro. The Valley is bordered by the Colorado River to the east and, in part, the Salton Sea to the west. Farther west lies the San Diego and Imperial County border. To the north is the Coachella Valley region of Riverside County, which together with Imperial Valley form the Salton Trough, or the Cahuilla Basin, also the county line of Imperial and Riverside counties, and to the south the international boundary with Mexico. The culture of the area blends those of the United States and Mexico, due to its regional history and geographic location along the international border. The Imperial Valley economy is based on agriculture. Imperial Valley was named by the Imperial Land Company, in the hopes of attracting settlers. It is now the home of the El Centro metropolitan area. Locally, the terms "Imperial Valley" and "Im ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mexicali
Mexicali (; ) is the capital city of the States of Mexico, Mexican state of Baja California. The city, which is the seat of the Mexicali Municipality, has a population of 689,775, according to the 2010 census, while the Calexico–Mexicali, Calexico–Mexicali metropolitan area is home to 1,000,000 inhabitants on both sides of the Mexico–United States border. Mexicali is a regional economic and cultural hub for the border region of The Californias. Mexicali was founded at the turn of the 20th century, when the region's agricultural economy experienced a period of boom. The city rapidly expanded throughout the 20th century, owing to the proliferation of maquiladoras in the city, making the Mexicali economy more interconnected with businesses from across the border. Today, Mexicali is a major manufacturing center and an emerging tourist destination. History The Spaniards arrived in the area after crossing the Sonoran Desert's "Camino del Diablo" or Devil's Road. This led to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
