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Sand Dune Ecology
Sand dune ecology describes the biological and physico-chemical interactions that are a characteristic of sand dunes. Sand dune systems are excellent places for biodiversity, partly because they are not very productive for agriculture, and partly because disturbed, stressful, and stable habitats are present in proximity to each other. Many of them are protected as nature reserves, and some are parts of larger conservation areas, incorporating other coastal habitats like salt marshes, mud flats, grasslands, scrub, and woodland. Plant habitat Sand dunes provide a range of habitats for a range of unusual, interesting and characteristic plants that can cope with disturbed habitats. In the UK these may include restharrow ''Ononis repens'', sand spurge ''Euphorbia arenaria'' and ragwort ''Senecio vulgaris'' - such plants are termed ruderals. Other very specialised plants are adapted to the accretion of sand, surviving the continual burial of their shoots by sending up very rapid vert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sand Dune
A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, flat regions covered with wind-swept sand or dunes with little or no vegetation are called '' ergs'' or ''sand seas''. Dunes occur in different shapes and sizes, but most kinds of dunes are longer on the stoss (upflow) side, where the sand is pushed up the dune, and have a shorter ''slip face'' in the lee side. The valley or trough between dunes is called a ''dune slack''. Dunes are most common in desert environments, where the lack of moisture hinders the growth of vegetation that would otherwise interfere with the development of dunes. However, sand deposits are not restricted to deserts, and dunes are also found along sea shores, along streams in semiarid climates, in areas of glacial outwash, and in other areas where poorly cemented ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phragmites Australis
''Phragmites australis'', known as the common reed, is a species of plant. It is a broadly distributed wetland grass that can grow up to tall. Description ''Phragmites australis'' commonly forms extensive stands (known as reed beds), which may be as much as or more in extent. Where conditions are suitable it can also spread at or more per year by horizontal runners, which put down roots at regular intervals. It can grow in damp ground, in standing water up to or so deep, or even as a floating mat. The erect stems grow to tall, with the tallest plants growing in areas with hot summers and fertile growing conditions. The leaves are long and broad. The flowers are produced in late summer in a dense, dark purple panicle, about long. Later the numerous long, narrow, sharp pointed spikelets appear greyer due to the growth of long, silky hairs. These eventually help disperse the minute seeds. Taxonomy Recent studies have characterized morphological distinctions between the int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dunes
A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, flat regions covered with wind-swept sand or dunes with little or no vegetation are called '' ergs'' or ''sand seas''. Dunes occur in different shapes and sizes, but most kinds of dunes are longer on the stoss (upflow) side, where the sand is pushed up the dune, and have a shorter ''slip face'' in the lee side. The valley or trough between dunes is called a ''dune slack''. Dunes are most common in desert environments, where the lack of moisture hinders the growth of vegetation that would otherwise interfere with the development of dunes. However, sand deposits are not restricted to deserts, and dunes are also found along sea shores, along streams in semiarid climates, in areas of glacial outwash, and in other areas where poorly cemented sa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sand Dune Stabilization
Sand dune stabilization is a coastal management practice designed to prevent erosion of sand dunes. Sand dunes are common features of shoreline and desert environments. Dunes provide habitat for highly specialized plants and animals, including rare and endangered species. They can protect beaches from erosion and recruit sand to eroded beaches. Dunes are threatened by human activity, both intentional and unintentional (see sand theft and sand mining). Countries such as the United States, Australia, Canada, New Zealand, the United Kingdom, and Netherlands, operate significant dune protection programs. Stabilizing dunes involves multiple actions. Planting vegetation reduces the impact of wind and water. Wooden sand fences can help retain sand and other material needed for a healthy sand dune ecosystem. Footpaths protect dunes from damage from foot traffic. The location of the dune limits the types of plant that can thrive there. Beach dunes consist of the ''foredune'', the angled si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psammosere
A psammosere is a seral community, an ecological succession that began life on newly exposed coastal sand. Most common psammoseres are sand dune systems. In a psammosere, the organisms closest to the sea will be pioneer species: salt-tolerant species such as littoral algae and glasswort with marram grass stabilising the dunes. Progressing inland many characteristic features change and help determine the natural succession of the dunes. For instance, the drainage slows down as the land becomes more compact and has better soils, and the pH drops as the proportion of seashell fragments reduces and the amount of humus increases. Sea purslane, sea lavender, meadow grass and heather eventually grade into a typical non-maritime terrestrial eco-system. The first trees (or pioneer trees) that appear are typically fast-growing trees such as birch, willow or rowan. In turn these will be replaced by slow-growing, larger trees such as ash and oak. This is the climax community, defined as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecological Succession
Ecological succession is the process of change in the species structure of an ecological community over time. The time scale can be decades (for example, after a wildfire) or more or less. Bacteria allows for the cycling of nutrients such as carbon, nitrogen and sulphur. The community begins with relatively few pioneering plants and animals and develops through increasing complexity until it becomes stable or self-perpetuating as a climax community. The "engine" of succession, the cause of ecosystem change, is the impact of established organisms upon their own environments. A consequence of living is the sometimes subtle and sometimes overt alteration of one's own environment. Succession is a process by which an ecological community undergoes more or less orderly and predictable changes following a disturbance or the initial colonization of a new habitat. Succession may be initiated either by formation of new, unoccupied habitat, such as from a lava flow or a severe landsl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coastal Management
Coastal management is defence against flooding and erosion, and techniques that stop erosion to claim lands. Protection against rising sea levels in the 21st century is crucial, as sea level rise accelerates due to climate change. Changes in sea level damage beaches and coastal systems are expected to rise at an increasing rate, causing coastal sediments to be disturbed by tidal energy. Coastal zones occupy less than 15% of the Earth's land area, while they host more than 40% of the world population. Nearly 1.2 billion people live within 100 km of shoreline and 100 m of sea level, with an average density 3 times higher than the global average for population. With three-quarters of the world population expected to reside in the coastal zone by 2025, human activities originating from this small land area will impose heavy pressure on coasts. Coastal zones contain rich resources to produce goods and services and are home to most commercial and industrial activities. Histor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blowout Grass
''Redfieldia'', known as blowout grass, is a monotypic genus in the grass family ( Poaceae). The sole species, ''Redfieldia flexuosa'', is native to sandhills in the western and central United States. The plants grow in small clusters, protecting each other from the harsh desert conditions. Description The flowering culms are tall. The inflorescence is an open panicle with solitary spikelets on narrow pedicels. Each spikelet has between two and six florets. The glumes have pointed tips and are narrower than the fertile lemma. The lemma has three veins and hairy margins. The glumes are persistent after fruiting. It spreads with elongated rhizomes. Distribution and habitat According to the United States Natural Resources Conservation Service (NRCS), blowout grass is found in thirteen states, including Arizona, Colorado, Illinois, Kansas, Montana, North Dakota, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, Utah, and Wyoming.USDA, Natural Resources Conservation Service, "Pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Groundwater
Groundwater is the water present beneath Earth's surface in rock and soil pore spaces and in the fractures of rock formations. About 30 percent of all readily available freshwater in the world is groundwater. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock become completely saturated with water is called the water table. Groundwater is recharged from the surface; it may discharge from the surface naturally at springs and seeps, and can form oases or wetlands. Groundwater is also often withdrawn for agricultural, municipal, and industrial use by constructing and operating extraction wells. The study of the distribution and movement of groundwater is hydrogeology, also called groundwater hydrology. Typically, groundwater is thought of as water flowing through shallow aquifers, but, in the technical sense, it can also contain soil moisture, permafros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salt Marsh
A salt marsh or saltmarsh, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open saltwater or brackish water that is regularly flooded by the tides. It is dominated by dense stands of salt-tolerant plants such as herbs, grasses, or low shrubs. These plants are terrestrial in origin and are essential to the stability of the salt marsh in trapping and binding sediments. Salt marshes play a large role in the aquatic food web and the delivery of nutrients to coastal waters. They also support terrestrial animals and provide coastal protection. Salt marshes have historically been endangered by poorly implemented coastal management practices, with land reclaimed for human uses or polluted by upstream agriculture or other industrial coastal uses. Additionally, sea level rise caused by climate change is endangering other marshes, through erosion and submersion of otherwise tidal marshes. However, r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blowout (geology)
Blowouts are sandy depressions in a sand dune ecosystem (psammosere) caused by the removal of sediments by wind. Commonly found in coastal settings and margins of arid areas, blowouts tend to form when wind erodes patches of bare sand on stabilized vegetated dunes. Generally, blowouts do not form on actively flowing dunes due to the fact that the dunes need to be bound to some extent, for instance by plant roots. These depressions usually start on the higher parts of stabilized dunes on account of the more considerable desiccation and disturbances occurring there, which allows for greater surface drag and sediment entrainment when the sand is bare. Most of the time, exposed areas become quickly re-vegetated before they can become blowouts and expand; however, when circumstances are favourable, wind erosion can gouge the exposed surface and create a tunneling effect which increases local wind speed. A depression may then develop until it hits a non-erodible substrate, or morphol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Links (golf)
A links is the oldest style of golf course, first developed in Scotland. Links courses are generally built on sandy coastland that offers a firmer playing surface than parkland and heathland courses. The word "links" comes via the Scots language from the Old English word '' hlinc'': "rising ground, ridge" and refers to an area of coastal sand dunes and sometimes to open parkland; it is cognate with ''lynchet''. "Links" can be treated as singular even though it has an "s" at the end and occurs in place names that precede the development of golf, for example Lundin Links in Fife. It also retains this more general meaning in standard Scottish English. Links land is typically characterised by dunes, an undulating surface, and a sandy soil unsuitable for arable farming but which readily supports various indigenous browntop bent and red fescue grasses. Together, the soil and grasses result in the firm turf associated with links courses and the 'running' game. The hard surface ty ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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