Misplaced Pages

#557442

49-462: The Margaret River is a river in southwest Western Australia . In a small catchment, it is the eponym of the town and tourist region of Margaret River . The river arises from a catchment of just 40 square kilometres in the Whicher Range . Ombak tujuh is a "big-wave" spot. The middle reaches pass through land cleared for agriculture, especially viticulture . There is a weir across

98-581: A biodiversity hotspot – a biological community with a large number of different species – that is under threat by human activity. The California chaparral and woodlands ecoregion , of the Mediterranean forests, woodlands, and scrub biome , has three sub-ecoregions with ecosystem – plant community subdivisions: For the numerous individual plant and animal species found within the California chaparral and woodlands ecoregion, see: Some of

147-499: A broad coastal plain 20-120 kilometres wide, transitioning to gently undulating uplands made up of weathered granite , gneiss and laterite . Bluff Knoll in the Stirling Range is the highest peak in the region, at 1,099 metres (3,606 ft) elevation. Desert and xeric shrublands lie to the north and east across the centre of Australia, separating Southwest Australia from the other Mediterranean and humid-climate regions of

196-434: A fire. Plants that are long-lived in the seed bank or serotinous with induced germination after fire include chamise , Ceanothus, and fiddleneck . Some chaparral plant communities may grow so dense and tall that it becomes difficult for large animals and humans to penetrate, but may be teeming with smaller fauna in the understory. The seeds of many chaparral plant species are stimulated to germinate by some fire cue (heat or

245-467: A high ratio of magnesium and iron to calcium and potassium, that are also generally low in essential nutrients such as nitrogen. Another phytogeography system uses two California chaparral and woodlands subdivisions: the cismontane chaparral and the transmontane (desert) chaparral. Cismontane chaparral ("this side of the mountain") refers to the chaparral ecosystem in the Mediterranean forests, woodlands, and scrub biome in California, growing on

294-405: A high-intensity crown-fire regime, meaning that fires consume nearly all the above ground growth whenever they burn, with a historical frequency of 30 to 150 years or more. A detailed analysis of historical fire data concluded that fire suppression activities have been ineffective at excluding fire from southern California chaparral, unlike in ponderosa pine forests. In addition, the number of fires

343-439: A native shrubland to non-native annual grassland and drastically reduce species diversity, especially under drought brought about by climate change. There are two older hypotheses relating to California chaparral fire regimes that caused considerable debate in the past within the fields of wildfire ecology and land management. Research over the past two decades have rejected these hypotheses: The perspective that older chaparral

392-520: A year. This makes the chaparral most vulnerable to fire in the late summer and fall. The chaparral ecosystem as a whole is adapted to be able to recover from naturally infrequent, high-intensity fire (fires occurring between 30 and 150 years or more apart); indeed, chaparral regions are known culturally and historically for their impressive fires. (This does create a conflict with human development adjacent to and expanding into chaparral systems.) Additionally, Native Americans burned chaparral near villages on

441-668: Is a biogeographic region in Western Australia . It includes the Mediterranean-climate area of southwestern Australia, which is home to a diverse and distinctive flora and fauna. The region is also known as the Southwest Australia Global Diversity Hotspot . The region includes the Mediterranean forests, woodlands, and scrub ecoregions of Western Australia. The region covers 356,717 km , consisting of

490-885: Is an important pollinator for several southwestern plants including Banksia attenuata , Banksia coccinea , and Adenanthos cuneatus . Other mammals endemic to Southwest Australia are the western brush wallaby ( Macropus irma ) and the quokka ( Setonix brachyurus ). Southwest Australia is an Endemic Bird Area , with several endemic species of birds including the long-billed black cockatoo ( Zanda baudinii ), western corella ( Cacatua pastinator ), noisy scrubbird ( Atrichornis clamosus ), red-winged fairywren ( Malurus elegans ), western bristlebird ( Dasyornis longirostris ), black-throated whipbird ( Psophodes nigrogularis ), white-breasted robin ( Eopsaltria georgianus ), and red-eared firetail ( Stagonopleura oculata ). The western rufous bristlebird ( Dasyornis broadbenti litoralis ), an endemic subspecies of rufous bristlebird ,

539-427: Is increasing in step with population growth and exacerbated by climate change. Chaparral stand age does not have a significant correlation to its tendency to burn. Large, infrequent, high-intensity wildfires are part of the natural fire regime for California chaparral. Extreme weather conditions (low humidity, high temperature, high winds), drought, and low fuel moisture are the primary factors in determining how large

SECTION 10

#1732765835558

588-604: Is now extinct. The World Wide Fund for Nature and Interim Biogeographic Regionalisation for Australia (IBRA) divide the region into six ecoregions and ten biogeographic regions: The transitional Coolgardie, Hampton, and Yalgoo bioregions are generally drier than the rest of the Southwest. They considered part of Southwest Australia by the WWF, but are considered part of the Central Australian or Eremaean Region by

637-478: Is often open, with only about 50 percent of the ground covered. Individual shrubs can reach up to 10 feet (3.0 m) in height. Transmontane chaparral or desert chaparral is found on the eastern slopes of major mountain range systems on the western sides of the deserts of California . The mountain systems include the southeastern Transverse Ranges (the San Bernardino and San Gabriel Mountains ) in

686-492: Is similar to the observation that fire suppression and other human-caused disturbances in dry, ponderosa pine forests in the Southwest of the United States has unnaturally increased forest density. Historically, mixed-severity fires likely burned through these forests every decade or so, burning understory plants, small trees, and downed logs at low-severity, and patches of trees at high-severity. However, chaparral has

735-746: Is unhealthy or unproductive may have originated during the 1940s when studies were conducted measuring the amount of forage available to deer populations in chaparral stands. However, according to recent studies, California chaparral is extraordinarily resilient to very long periods without fire and continues to maintain productive growth throughout pre-fire conditions. Seeds of many chaparral plants actually require 30 years or more worth of accumulated leaf litter before they will successfully germinate (e.g., scrub oak, Quercus berberidifolia ; toyon, Heteromeles arbutifolia ; and holly-leafed cherry, Prunus ilicifolia ). When intervals between fires drop below 10 to 15 years, many chaparral species are eliminated and

784-892: The Mojave Desert north and northeast of the Los Angeles basin and Inland Empire; and the northern Peninsular Ranges (San Jacinto, Santa Rosa , and Laguna Mountains ), which separate the Colorado Desert (western Sonoran Desert ) from lower coastal Southern California . It is distinguished from the cismontane chaparral found on the coastal side of the mountains, which experiences higher winter rainfall. Naturally, desert chaparral experiences less winter rainfall than cismontane chaparral. Plants in this community are characterized by small, hard ( sclerophyllic ) evergreen (non- deciduous ) leaves. Desert chaparral grows above California's desert cactus scrub plant community and below

833-640: The Western Australian Herbarium . Southwest Australia has several permanent rivers and streams, including the Swan – Avon system, the Blackwood River , and other short rivers. The perennial rivers drain from the interior plateau and Darling Range across the coastal plain. Their flow is strongly seasonal, corresponding to the Southwest's wet winter–dry summer weather pattern. The perennial streams extend from east of Esperance on

882-457: The chaparral , matorral , maquis , and fynbos shrublands found in other Mediterranean-type regions. The region has generally nutrient-poor sandy or lateritic soils, which has encouraged rich speciation of plants adapted to specific ecological niches. The region hosts a great diversity of endemic species, notably among the protea family ( Proteaceae ). Southwest Australia is home to many endemic carnivorous plants , including more than half

931-588: The desert shrubland habitat and chaparral plant community growing in the rainshadow of these ranges. Transmontane chaparral features xeric desert climate, not Mediterranean climate habitats, and is also referred to as desert chaparral . Desert chaparral is a regional ecosystem subset of the deserts and xeric shrublands biome , with some plant species from the California chaparral and woodlands ecoregion . Unlike cismontane chaparral, which forms dense, impenetrable stands of plants, desert chaparral

980-557: The pinyon-juniper woodland . It is further distinguished from the deciduous sub-alpine scrub above the pinyon-juniper woodlands on the same side of the Peninsular ranges. Due to the lower annual rainfall (resulting in slower plant growth rates) when compared to cismontane chaparral, desert chaparral is more vulnerable to biodiversity loss and the invasion of non-native weeds and grasses if disturbed by human activity and frequent fire. Transmontane (desert) chaparral typically grows on

1029-639: The scrub oak ". In its natural state, chaparral is characterized by infrequent fires, with natural fire return intervals ranging between 30 years and over 150 years. Mature chaparral (at least 60 years since time of last fire) is characterized by nearly impenetrable, dense thickets (except the more open desert chaparral). These plants are flammable during the late summer and autumn months when conditions are characteristically hot and dry. They grow as woody shrubs with thick, leathery, and often small leaves, contain green leaves all year (are evergreen ), and are typically drought resistant (with some exceptions ). After

SECTION 20

#1732765835558

1078-417: The 1960s. The summer of 2021/22 was the hottest on record. Southwest Australia is recognised as a floristic province . Vegetation in the region is mainly woody, including forests , woodlands , shrublands , and heathlands , but no grasslands . Predominant vegetation types are Eucalyptus woodlands, eucalyptus-dominated mallee shrublands, and kwongan shrublands and heathlands, which correspond to

1127-468: The California Academy of Sciences, Mediterranean shrubland contains more than 20 percent of the world's plant diversity. The word chaparral is a loanword from Spanish chaparro , meaning place of the scrub oak , which itself comes from a Basque word, txapar , that has the same meaning. Conservation International and other conservation organizations consider chaparral to be

1176-418: The chaparral biota native to California, all of which tend to regrow quickly after fires, include: The complex ecology of chaparral habitats supports a very large number of animal species. The following is a short list of birds which are an integral part of the cismontane chaparral ecosystems. Transmontane chaparral or desert chaparral — transmontane ("the other side of the mountain") chaparral —refers to

1225-400: The chemicals from smoke or charred wood). During the time shortly after a fire, chaparral communities may contain soft-leaved herbaceous, fire following annual wildflowers and short-lived perennials that dominate the community for the first few years – until the burl resprouts and seedlings of chaparral shrub species create a mature, dense overstory. Seeds of annuals and shrubs lie dormant until

1274-425: The coastal plain to promote plant species for textiles and food. Before a major fire, typical chaparral plant communities are dominated by manzanita , chamise Adenostoma fasciculatum and Ceanothus species, toyon (which can sometimes be interspersed with scrub oaks ), and other drought-resistant shrubs with hard ( sclerophyllous ) leaves; these plants resprout (see resprouter ) from underground burls after

1323-414: The continent. The region has a wet-winter, dry-summer Mediterranean climate , one of five such regions in the world. During the winter months, westerly winds bring cool weather, clouds, and rainfall to Southwest Australia. In the summer months, the lower-latitude anticyclonic belt, with generally dry easterly winds, moves southwards, increasing temperatures and decreasing rainfall. Tropical cyclones , off

1372-402: The diadromous common galaxias ( Galaxias maculatus ) and spotted galaxias ( Galaxias truttaceus ) have adapted so they can live their life-cycle and reproduce in fresh water. The southwestern snake-necked turtle ( Chelodina colliei ) and western swamp turtle ( Pseudemydura umbrina ) are aquatic species endemic to Southwest Australia. The first evidence of human habitation of the region

1421-525: The eastern side of central Mexico's mountain chains, all having summer rains in contrast to the Mediterranean climate of other chaparral formations. Chaparral comprises 9% of California's wildland vegetation and contains 20% of its plant species. See US Forest Service map and details of distribution and occurrence The name comes from the Spanish word chaparro , which translates to "place of

1470-511: The effects of human induced climate change . Average annual rainfall has declined as much as 20% since the 1970s, declining by 10-20 millimetres each decade. Summertime maximum temperatures have increased by 0.1º to 0.3º C per decade, and the average number of days per year over 40º C in Perth has doubled over the last century. Lower rainfall and higher temperatures have reduced stream flow and inflow into drinking water and irrigation catchments since

1519-740: The first rains following a fire, the landscape is dominated by small flowering herbaceous plants, known as fire followers, which die back with the summer dry period. Similar plant communities are found in the four other Mediterranean climate regions around the world, including the Mediterranean Basin (where it is known as maquis ), central Chile (where it is called matorral ), the South African Cape Region (known there as fynbos ), and in Western and Southern Australia (as kwongan ). According to

Margaret River - Misplaced Pages Continue

1568-462: The hibernation of reptiles and the moulting of swans are all helpful indicators that the seasons are changing. The first permanent European settlement in the region was in 1826 near present-day Albany . European settlers mostly dispossessed the Aboriginal inhabitants, and established extensive agriculture, including wheat, barley, canola, lupins, and oats. They also introduced sheep and cattle to

1617-446: The indicator plants of the California chaparral and woodlands ecoregion include: Chaparral soils and nutrient composition Chaparral characteristically is found in areas with steep topography and shallow stony soils, while adjacent areas with clay soils, even where steep, tend to be colonized by annual plants and grasses. Some chaparral species are adapted to nutrient-poor soils developed over serpentine and other ultramafic rock, with

1666-630: The interior of the deserts, such as in the upper New York Mountains within the Mojave National Preserve in the Mojave Desert. The California transmontane (desert) chaparral is found in the rain shadow deserts of the following: There is overlap of animals with those of the adjacent desert and pinyon-juniper communities. Chaparral is a coastal biome with hot, dry summers and mild, rainy winters. The chaparral area receives about 38–100 cm (15–39 in) of precipitation

1715-498: The land and vegetation. Evidence from lake and estuarine sediments and firsthand accounts suggest that fire intervals in well-settled areas were frequent – from one to ten years – compared to unoccupied forests and offshore islands, where fire intervals were 30 to 100 or more years. Frequent burning reduced tree cover and encouraged the growth of grasses, herbs, and low shrubs, fostering open woodlands and savannas and limiting areas of dense forest and thicket. Noongar peoples inhabited

1764-431: The loss of obligate seeding shrub species such as Manzanita spp. This high frequency disallows seeder plants to reach their reproductive size before the next fire and the community shifts to a sprouter-dominance. If high frequency fires continue over time, obligate resprouting shrub species can also be eliminated by exhausting their energy reserves below-ground. Today, frequent accidental ignitions can convert chaparral from

1813-586: The lower (3,500–4,500 feet (1,100–1,400 m) elevation) northern slopes of the southern Transverse Ranges (running east to west in San Bernardino and Los Angeles counties) and on the lower (2,500–3,500 feet (760–1,070 m)) eastern slopes of the Peninsular Ranges (running south to north from lower Baja California to Riverside and Orange counties and the Transverse Ranges). It can also be found in higher-elevation sky islands in

1862-549: The next fire creates the conditions needed for germination. Several shrub species such as Ceanothus fix nitrogen, increasing the availability of nitrogen compounds in the soil. Because of the hot, dry conditions that exist in the California summer and fall, chaparral is one of the most fire-prone plant communities in North America. Some fires are caused by lightning, but these are usually during periods of high humidity and low winds and are easily controlled. Nearly all of

1911-567: The region. European settlement also changed the fire regime established by the Aboriginal inhabitants of the land. 109,445 km , or 22.13%, of Southwest Australia's land area is in protected areas. Chaparral Many chaparral shrubs have hard sclerophyllous evergreen leaves, as contrasted with the associated soft-leaved, drought-deciduous , scrub community of coastal sage scrub , found often on drier, southern facing slopes. Three other closely related chaparral shrubland systems occur in southern Arizona , western Texas , and along

1960-447: The river just above the town. The mouth of the river is a small estuary, closed to the ocean by a sandbar that opens only seasonally. Margaret River is presumed to be named after Margaret Wyche, cousin of John Garrett Bussell (founder of Busselton ) in 1832. 33°56′43.28″S 115°4′26.79″E  /  33.9453556°S 115.0741083°E  / -33.9453556; 115.0741083 Southwest Australia Southwest Australia

2009-666: The sea. The exclusively freshwater species are endemic to Southwest Australia, as are two estuarine species. The salamanderfish ( Lepidogalaxias salamandroides ) is the sole species in the endemic family Lepidogalaxiidae. Salamanderfish can aestivate during the summer months, an adaptation to the region's dry summers. Other endemic species are the nightfish ( Bostockia porosa ), western mud minnow ( Galaxiella munda ), black-stripe minnow ( Galaxiella nigrostriata ), Balston’s pygmy perch ( Nannatherina balstoni ), western pygmy perch ( Nannoperca vittata ), and western galaxias ( Galaxias occidentalis ). Southwest Australian varieties of

Margaret River - Misplaced Pages Continue

2058-627: The shore of northern Western Australia during the December-to-March northern wet season, occasionally reach as far south as Perth before moving inland, bringing floods and damaging winds to the west coast and rain to the dry interior. Rainfall generally decreases from south to north, and with distance from the coast. The highest rainfall is typically in the Karri Forest Region between Pemberton and Walpole, up to 1,400 mm (55 inches) annually. The region has been experiencing

2107-690: The south coast to the Arrowsmith River north of Perth , most often in areas with 700 mm or more of annual rainfall. Arid regions separate Southwest Australia's freshwater habitats from Australia's other year-round rivers. As with its terrestrial flora, Southwest Australia's Mediterranean climate and biogeographic isolation has given rise to a distinct freshwater ecoregion with many endemic species. There are fifteen freshwater fish species, including nine exclusively freshwater species, three estuarine species adapted to brackish water, and three diadromous species that spend part of their life-cycle in

2156-465: The system is typically replaced by non-native, invasive, weedy grassland. The idea that older chaparral is responsible for causing large fires was originally proposed in the 1980s by comparing wildfires in Baja California and southern California. It was suggested that fire suppression activities in southern California allowed more fuel to accumulate, which in turn led to larger fires. This

2205-425: The very large wildfires are caused by human activity during periods of hot, dry easterly Santa Ana winds . These human-caused fires are commonly ignited by power line failures, vehicle fires and collisions, sparks from machinery, arson, or campfires. Though adapted to infrequent fires, chaparral plant communities can be eliminated by frequent fires. A high frequency of fire (less than 10-15 years apart) will result in

2254-747: The western (and coastal) sides of large mountain range systems, such as the western slopes of the Sierra Nevada in the San Joaquin Valley foothills, western slopes of the Peninsular Ranges and California Coast Ranges , and south-southwest slopes of the Transverse Ranges in the Central Coast and Southern California regions. In Central and Southern California chaparral forms a dominant habitat. Members of

2303-409: The western and southern portions of the region. The Noongar comprised 14 groups, which spoke distinct but mutually-intelligible languages. The Nyoongar seasonal calendar includes six different seasons in a yearly cycle. These are Birak, Bunuru, Djeran, Makuru, Djilba and Kambarang. Each of the six seasons represents and explains the seasonal changes seen annually. The flowering of many different plants,

2352-494: The world's species of sundews ( Drosera ), the bladderwort subgenus Polypompholyx , the Byblis gigantea complex of rainbow plants (composed of two species, Byblis lamellata and B. gigantea ), and the pitcher plant Cephalotus follicularis , sole species in the plant family Cephalotaceae. The honey possum ( Tarsipes rostratus ) is a tiny marsupial endemic to Southwest Australia that feeds on nectar and pollen, and

2401-453: Was 50,000 years ago at Devil's Lair by ancestors of today's Aboriginal people. Aboriginal populations were generally denser on the coastal plain and along the coastal forest edge, and in the interior woodlands and shrublands, particularly near permanent streams and river estuaries. Population was sparse in the forested areas of the south. Offshore islands were likely uninhabited. The Aboriginal inhabitants deliberately set fires to manage

#557442