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Positive Uses of Arundo Donax described here
Positive Uses of Arundo Donax described here
Date: 11/21/2011 3:15:18 PM ( 13 y ) ... viewed 2356 times
http://etd.uwc.ac.za/usrfiles/modules/etd/docs/etd_gen8Srv25Nme4_8478_1194347...
Impacts of the invasive reed
Arundo donax on biodiversity at the
community-ecosystem level
Gené Guthrie
1.2.2 Economic implications
Alien tree species (such as Pinus, Eucalyptus and Acacia) are important sources of pulp, timber and fuelwood, but in South Africa they are estimated to consume seven percent of available water (Le Maitre et al. 2000). The Nile perch Lates niloticus has great economic value in many African countries, but it has also caused the loss of endemic species and altered ecosystems (IUCN / SSG / ISSG 2004). Black wattle Acacia mearnsii has been used in Africa in commercial plantations for many years, and is also used in the production of soft leather (tannin compounds extracted from the bark); resins, thinners and adhesives (bark extract); building materials (timber); charcoal; and paper production (pulp and woodchips) (IUCN / SSG / ISSG 2004). It is highly invasive, producing large quantities of long-lived seeds and out-competing indigenous vegetation (IUCN / SSG / ISSG 2004).
Giant reed Arundo donax provides material for thatching, basketry and building construction. People rely on these products to support their families and households, and it becomes difficult to justify control or eradication of these alien species.
4. ARUNDO DONAX
Arundo donax L. (hereafter referred to as Arundo) is also known as Giant Reed, Bamboo Reed, Spanish Reed, Spanish Cane, Wild Cane and Arundo. Arundo belongs to the Arundineae tribe, along with Phragmites species (Renvoize 1980). Arundo is reported as indigenous to Egypt, India, Spain, Nepal, Eurasia, eastern Asia and the Mediterranean (Polunin & Huxley 1987; Fornell 1990; Hickman 1993). Most recent evidence reports Arundo as being indigenous to the Indian sub-continent (Bell 1997). Arundo has been intentionally distributed around the world because of its many uses (Dudley 2000). It does particularly well in areas with a Mediterranean- type climate. It is naturalized and invasive in many regions, including southern Africa, the Caribbean and Pacific Islands, South America, Australia, Southeast Asia, and United States through to Mexico (Hafliger & Scholz 1981). Arundo was first detected in the USA in the 1850s (Herrera & Dudley 2003), and today is invasive in sub-tropical, temperate, arid and semi-arid regions of North America (Langeland & Burks 1998).
Arundo is a hydrophyte, growing along lakes, streams, drains, and other wet sites (Bell 1997). Although it usually grows in wetter areas, it does not need a constant supply of water, and can grow on drier banks and roadsides. Arundo has pale green to blue-green leaves, and may be confused with bamboo and corn. Younger plants resemble the common reed Phragmites australis. Arundo is a perennial C3 grass species (Rossa et al. 1998), and stems may reach 10 metres in height (Dudley 2000). It usually grows in large stands many metres wide, and contains hundreds of stems per stand (Spencer et al. 2005). It does not produce viable seed in most areas where it has been introduced (Perdue 1958), and reproduction occurs almost entirely from rhizomes and stem fragments (Boose & Holt 1999). Fragments are usually carried by floodwaters
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into new habitats where they sprout new culms (Else 1996). Rhizomes are tough and fibrous, forming thick mats that penetrate deep into the soil (Mackenzie 2004). Each plant can have a root span of up to 12 metres in diameter (Jackson 1993).
Arundo forms one of the most biologically productive populations (Bell 1997). Ideal growth conditions would be low gradient riparian areas with well-drained soils (Perdue 1958), high water nutrient levels (such as at agricultural, industrial and residential wastewater discharge sites), low salinity (Grossinger et al. 1998), full sun, and high temperatures. Under these conditions Arundo produces more than 20 tons per hectare above-ground biomass (Perdue 1958), but even when conditions are not ideal, Arundo produces approximately three tons per hectare above-ground biomass (Christou 2001). Rieger & Kreager (1989) record Arundo growing as much as seven centimetres in one day, and up to eight metres in a few months. Arundo outcompetes indigenous woody species in terms of growth rate and height (Else 1996). Once Arundo is established, it spreads at a rapid rate, excluding most other species. Plant species most capable of competing with Arundo are those reproducing via rhizomes and seeds (Else 1996).
Arundo can tolerate a wide variety of ecological conditions (Perdue 1958), mostly due to its rhizomes and deeply penetrating roots. Individual plants can survive periods of drought or of excessive moisture. Arundo is primarily a freshwater species but can tolerate excessive salinity (Perdue 1958; Grossinger et al. 1998). It survives and flourishes in all types of soils, from heavy clays to loose sands and gravel (Perdue 1958). It is usually associated with higher soil nutrient levels than indigenous plants (Coffman et al. 2004). Arundo can survive low temperatures when dormant (during winter), but is vulnerable to damage by frosts after the start of spring growth (Decruyenaere and Holt 2001). Arundo does not appear to tolerate high elevation or inland environments where sustained freezing occurs (Team Arundo del Norte 1999a). Arundo is usually associated with rivers that have been physically disturbed or dammed, but it can invade indigenous stands of plant species, even in full shade (Bell 1997). Arundo is one of the few alien species that invades undisturbed or naturally disturbed systems (Rejmánek 1989), and does not need some form of human intervention to become established. However, disturbance has played a major role in the successful invasion and establishment of Arundo (Bell 1997), since certain human alteration of ecosystems (such as fertilizer addition, or cleared land and removed competition) provides more suitable conditions for its growth. Floods and anthropogenic modification to riparian environments have helped spread Arundo along river courses (Coffman
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et al. 2004). Recent nutrient loading of rivers is hypothesized to be a major factor contributing to Arundo invasion in California (di Castri 1991).
4.1 Uses
Arundo plants are often used as erosion control (Bell 1997), because the root masses stabilize stream banks and terraces (Zohary & Willis 1992).
Arundo has been suggested as a source of biomass for fuel energy production (Duke 1983).
It does not make a good livestock forage because the leaves mature and become unpalatable quickly.
Leaves may be woven into mats and baskets. Stems can be used for building material, plant supports, fences, screens, roofing, walking sticks,
measuring rods, fishing poles and brooms (Duke 1983; Usher 1974).
The stems are used make musical instruments like clarinets and bag-pipes (Usher 1974).
Young stems or branches can be used in roof thatching. The stem fibre can be used to make paper (Duke 1983). In Italy, the plant is used in the manufacture of rayon (Duke 1983).
Yellow dye may be made from the pollen (Moerman 1998).
Rhizomes are edible, raw or cooked. They can be dried out and ground into a powder to make bread, usually in conjunction with cereal flours (Chiej 1984).
They can be roasted or boiled (Coyle & Roberts 1975). Arundo is also used to treat dropsy (Duke & Wain 1981).
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November 22, 2011
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