The lawns are in sharp decline in more urbanized and cultivated areas, which justified a national program led by ten regional conservatories of natural areas with the counterpart program from 1998 to 2001 (LIFE). As part of green networks, network Natura 2000 European Ecological Network, the management strategies may be part of systemic approach to ecological network type (lawn service Florida Keys). For example, the Burgundy region offers orange network lawns in context of its regional pattern of ecological coherence (SRCE).
Lawns from an extensive pastoralism (meadows) are threatened mainly because of agricultural abandonment. They are part of "dry" lawns or "xeric" (the soil is very draining). They are self-sustained by the low capacity of soil to retain water from rainfall thus helping to maintain farmed and wild herbivores. This type of grass is extremely flowery and some plants in tourist areas are specifically protected.
Grasses (Poaceae) are a family of herbaceous plants, or very rarely woody variants, belonging to order Poales of monocots. With more than 820 genera and about 12,100 species described, grasses are the fourth family with highest species richness after composite, orchids and legumes; but it is definitely the first in economic importance global.
Most of these lawns exist naturally in presence of large wild herbivores. The aerohalines lawns are in immediate vicinity of sea, under the influence of wind and spray, even at high summer drought just above the rocks of foreshore or cliffs. Oligotrophic lawns located between 2,500 meters and about 3000 meters altitude in mountains. They tend to rise in sea level with global warming, as well as the forest floor above which they flourish.
They have leaves arranged alternately, typically composed sheath, ligule and limbo. Sheath tightly surrounds the stem, its margins overlap but do not fuse together (only occasionally can found forming a tube). Ligule membranous is a small appendage, or rarely a group of hairs (trichomes), located at the junction of blade with the sheath, on adaxial side.
They are generally herbs, although they may be woody like the tropicales, turfgrass, rhizomatous or stoloniferous bamboos. For the duration of its life cycle can annual, biennial or perennial. Annual grasses, as is logical to assume, reproduce only once during their life cycle -the case of wheat or oats, for example.
Perennial species, however, can reproduce several times annually or usually once. In first case they are called iteroparous most grass species, for example, and in second case, semelparous, as is the case of different species. They have cylindrical stems elliptical in cross-section, articulated, commonly called rods, usually with solid nodes and hollow (but may be totally solid as in case of maize and some bamboos). The knots are somewhat thicker than they start as internodes, leaves and buds. Internodes are sometimes rather flattened in area where the branches are developed.
Lawns are habitats in some areas have declined greatly. Many of these grasslands have been destroyed or fragmented eutrophic, by urbanization, overgrazing, intensive agriculture (large scale cultivation of legumes, cereals, leys, herbicides), agricultural abandonment when the zone and lack of shepherds, all-terrain vehicles (motorcycles, quads), tourist and leisure activities, military exercises, etc. For example, for Western Europe, "about 80 to 90% of dry grasslands still present at the end of nineteenth century have disappeared from, while - as of other oligotrophic also declining areas (ponds, bogs acids, acid moorland ...) they hosted a substantial part of biodiversity (still as an example, "the 40 species of Orthoptera present in Nord-Pas-region -Calais, 15 may be considered subservient to dry grassland. "
Lawns from an extensive pastoralism (meadows) are threatened mainly because of agricultural abandonment. They are part of "dry" lawns or "xeric" (the soil is very draining). They are self-sustained by the low capacity of soil to retain water from rainfall thus helping to maintain farmed and wild herbivores. This type of grass is extremely flowery and some plants in tourist areas are specifically protected.
Grasses (Poaceae) are a family of herbaceous plants, or very rarely woody variants, belonging to order Poales of monocots. With more than 820 genera and about 12,100 species described, grasses are the fourth family with highest species richness after composite, orchids and legumes; but it is definitely the first in economic importance global.
Most of these lawns exist naturally in presence of large wild herbivores. The aerohalines lawns are in immediate vicinity of sea, under the influence of wind and spray, even at high summer drought just above the rocks of foreshore or cliffs. Oligotrophic lawns located between 2,500 meters and about 3000 meters altitude in mountains. They tend to rise in sea level with global warming, as well as the forest floor above which they flourish.
They have leaves arranged alternately, typically composed sheath, ligule and limbo. Sheath tightly surrounds the stem, its margins overlap but do not fuse together (only occasionally can found forming a tube). Ligule membranous is a small appendage, or rarely a group of hairs (trichomes), located at the junction of blade with the sheath, on adaxial side.
They are generally herbs, although they may be woody like the tropicales, turfgrass, rhizomatous or stoloniferous bamboos. For the duration of its life cycle can annual, biennial or perennial. Annual grasses, as is logical to assume, reproduce only once during their life cycle -the case of wheat or oats, for example.
Perennial species, however, can reproduce several times annually or usually once. In first case they are called iteroparous most grass species, for example, and in second case, semelparous, as is the case of different species. They have cylindrical stems elliptical in cross-section, articulated, commonly called rods, usually with solid nodes and hollow (but may be totally solid as in case of maize and some bamboos). The knots are somewhat thicker than they start as internodes, leaves and buds. Internodes are sometimes rather flattened in area where the branches are developed.
Lawns are habitats in some areas have declined greatly. Many of these grasslands have been destroyed or fragmented eutrophic, by urbanization, overgrazing, intensive agriculture (large scale cultivation of legumes, cereals, leys, herbicides), agricultural abandonment when the zone and lack of shepherds, all-terrain vehicles (motorcycles, quads), tourist and leisure activities, military exercises, etc. For example, for Western Europe, "about 80 to 90% of dry grasslands still present at the end of nineteenth century have disappeared from, while - as of other oligotrophic also declining areas (ponds, bogs acids, acid moorland ...) they hosted a substantial part of biodiversity (still as an example, "the 40 species of Orthoptera present in Nord-Pas-region -Calais, 15 may be considered subservient to dry grassland. "
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