Biomes, eco-regions and biodiversity hotspots Rich Knight, Biodiversity & Conservation Biology UWCknight.email@example.com Note: Additional notes in text - all slides with the green tick are examinable
Biomes (Terrestrial) Spatial units with "Ecological Similarity" with respect to communities of • Plants, • Animals, • Soil Organisms. Defined based on • Plant structures (such as trees, shrubs, and grasses), • Leaf types (such as broadleaf and needle leaf), • Plant spacing (forest, woodland, savanna), • Climate (moisture and temperature).
Biome characteristics Not defined by • genetic, • taxonomic, or • historical similarities Biomes are often identified with particular patterns of • Ecological succession e.g. Savanna, • Climax vegetation e.g. Tropical Rainforest.
Biome Biodiversity Determined especially by fauna e.g. mammals Subdominant plant forms depends on • Abiotic factors (soil, light etc) • Biomass productivity of the dominant vegetation Species diversity tends to be higher in biomes with particular patterns of • higher net primary productivity, • higher moisture availability • higher temperatures
Biome - distribution Major factor determining their distribution are • Latitude: arctic, boreal, temperate, subtropical, tropical • Humidity: humid, semi-humid, semi-arid, and arid. • seasonal variation: rainfall may be distributed evenly throughout the year, or possess seasonal variations. • dry summer, wet winter: most regions of the earth receive most of their rainfall during the summer months; Mediterranean climate regions receive their rainfall during the winter months. • Elevation: increasing elevation causes a distribution of habitat types similar to that of increasing latitude. Biodiversity increases towards the equator and with increased humidity.
Udvardy Classification (12) • Tropical humid forests • Subtropical and temperate rainforests or woodlands • Temperate broad-leaf forests or woodlands and sub-polar deciduous thickets • Temperate needle-leaf forests or woodlands • Evergreen sclerophyllous forests, scrub, or woodlands • Tropical dry or deciduous forests (including Monsoon forests) or woodlands • Temperate grasslands • Warm deserts and semi-deserts • Cold-winter (continental) deserts and semi-deserts • Tundra communities and barren Arctic deserts • Mixed mountain and highland systems with complex zonation • Mixed island systems
WWF: major habitat types (14) • Tundra (arctic) • Boreal forests/taiga (subarctic, humid) • Temperate coniferous forests (temperate, humid to semi-humid) • Temperate broadleaf and mixed forests (temperate, humid) • Temperate grasslands, savannas, and shrublands (temperate, semi-arid) • Mediterranean forests, woodlands, and shrub (temperate warm, semi-humid to semi-arid with winter rainfall) • Tropical and subtropical coniferous forests (tropical and subtropical, semi-humid) • Tropical and subtropical moist broadleaf forests (tropical and subtropical, humid)
WWF ... /continued • Tropical and subtropical dry broadleaf forests (tropical and subtropical, semi-humid) • Tropical and subtropical grasslands, savannas, and shrublands (tropical and subtropical, semi-arid) • Montane grasslands and shrublands (alpine or montane climate) • Deserts and xeric shrublands (temperate to tropical, arid) • Mangrove (subtropical and tropical, salt water inundated) • Flooded grasslands and savannas (temperate to tropical, fresh or brackish water inundated) Further divided into 825 terrestrial eco-regions. WWF identified 200 ecoregions for conservation prioritization.
Aquatic biomes • Continental shelf • Littoral/Intertidal zone • Riparian • Pond/Lake • Coral reef • Kelp forest • Pack ice • Hydrothermal vents • Cold seeps • Benthic zone • Pelagic zone • Epipelagic • Mesopelagic • Bathypelagic • Abyssopelagic • Hadopelagic • Neritic zone
34 Biodiversity Hotspots >70% habitat lost, >1 500 endemic vascular plant spp. Investment criteria for Conservation International’s prioritization.
Defining Biodiversity Hotspots Coined by Norman Myers in two articles in “The Environmentalist” (1988 & 1990) Revised by Myers “Hotspots: Earth’s Biologically Richest and Most Endangered Terrestrial Ecoregions” (1999) • Thirty-four areas are identified and support nearly 60% of the world's plant, bird, mammal, reptile, and amphibian species • Half of the world’s plant species and 42 percent of all terrestrial vertebrate species are endemic to hotspots • Covers only 2.3 percent of the Earth's land surface • Therefore defined as "a biogeographic region with a significant reservoir of biodiversity that is threatened with destruction"
Critique of Biodiv. Hotspots High profile of the biodiversity hotspots concept - World Banks funding has resulted in considerable criticism • Inadequate representation of other species richness (e.g. total species richness or threatened species richness). • Inadequate representation of taxa other than vascular plants (e.g. vertebrates, or fungi). • No provision to protect smaller scale richness • No provision for changing land use patterns. • Do not consider ecosystem services • Do not consider phylogenetic diversity.
Global Conservation Do not address the concept of cost The purpose of biodiversity hotspots is not simply to identify regions that are of high biodiversity value, but to prioritise conservation spending. The regions identified include regions in the developed world (e.g. the California Floristic Province), alongside regions in the developing world (e.g. Madagascar). The cost of land is likely to vary between these regions by an order of magnitude or more, but the biodiversity hotspots do not consider the conservation importance of this difference. http://www.biodiversityhotspots.org http://en.wikipedia.org/wiki/Biodiversity_hotspots
North and Central America California Floristic Province Caribbean Islands Madrean Pine-Oak Woodlands Mesoamerica 2 3 3 1 4 4
South America Atlantic Forest Cerrado Chilean Winter Rainfall- Valdivian Forests Tumbes-Chocó-Magdalena Tropical Andes 2 5 5 5 3 3 3 1 1 4 4
Europe and Central Asia Caucasus Irano-Anatolian Mediterranean Basin Mountains of Central Asia 2 2 2 3 3 3 3 3 1 4 4
Africa Cape Floristic Region Coastal Forests of Eastern Africa Eastern Afromontane Guinean Forests of West Africa Horn of Africa Madagascar and the Indian Ocean Islands Maputaland-Pondoland-Albany Succulent Karoo 2 2 7 5 2 8 7 6 3 3 3 3 1 4 4 4
Asia-Pacific 13 12 11 10 13 East Melanesian Islands Himalaya Indo-Burma Japan Mountains of Southwest China New Caledonia New Zealand Philippines Polynesia-Micronesia Southwest Australia Sundaland Wallacea Western Ghats and Sri Lanka 8 9 9 2 7 6 5 9 3 1 4 4
California Floristic Province • Mediterranean-type climate of North America • High levels of plant endemism • the giant sequoia, the planet's largest living organism and less massive relative, the coastal redwood. • Has a number of threatened endemic species such as the giant kangaroo rat and the desert slender salamander • Some of the last individuals of the Critically Endangered California condor • Wilderness destruction caused by commercial farming • Heavily threatened by the expansion of urban areas, pollution, and road construction.
California Floristic Province Recorded extinctions since 1500. *Categories I-IV afford higher levels of protection.
Caribbean Islands • Diverse ecosystems from montane cloud forests to cactus scrublands • Devastated by deforestation • Hotspot has dozens of threatened species, including two species of solenodon (giant shrews) and the Cuban crocodile. • The hotspot is also remarkable for the diminutive nature of much of its fauna, boasting the world's smallest bird (the tiny bee hummingbird) and smallest snake.
Includes Mexico's main mountain chains, mountaintops in Baja California and southern US An area of rugged mountainous terrain, high relief, and deep canyons. Quarter of Mexico's plant species are found here, many of which are endemic. The pine forests of Michoaca'n provide over-wintering sites for the annual monarch butterfly migrations Excessive logging is causing destruction of pine forests and consequent loss of habitat. Madrean Pine-Oak Woodlands
The Mesoamerican forests are the third largest among the world's hotspots. Endemic species include quetzals, howler monkeys, and 17,000 plant species. Is also a corridor for many Neotropical migrant bird species. The hotspot's montane forests are important for amphibians, many endemic species of which are in dramatic decline due to an interaction between habitat loss, fungal disease and climate change. Mesoamerica
Atlantic Forest • Occurs in tropical South America includes 20,000 plant species, and 40% are endemic. • Only 10 percent or less remains. • More than 24 Critically Endangered vertebrate species including three species of lion tamarins and six bird species • Hotspot has almost 950 avian species with endemics such as the red-billed curassow, the Brazilian merganser. • Sugarcane plantations and later, coffee plantations has contributed to significant habitat destruction over the centuries • With massive urban growth of Rio de Janeiro and Sao Paulo threaten what remains of this hotspot.
Comprising 21% of Brazil Most extensive woodland-savanna in South America. Has a pronounced dry season and supports a unique array of drought- and fire- adapted plant species Numerous endemic bird species. Large mammals such as the giant anteater, giant armadillo, jaguar and maned wolf still survive despite rapid expansion of Brazil's agricultural frontier, which focuses primarily on soy and corn. Ranching is another major threat to the region, as it produces almost 40 million cattle a year. Cerrado
Isolated by being bounded by the Pacific Ocean, the Andes Mountains, and the Atacama Desert. These forests have a rich endemic flora and fauna. Protection from logging now exists. Rare fauna include Andean cat, the mountain vizcacha, & Andean condor. Reptilian, amphibian, and freshwater fish endemism is high. Threats include overgrazing, invasive species, & urbanization. Major hydroelectric dams and coastal development are specific problems facing the conservation of this hotspot. Chilean Winter Rainfall-Valdivian Forests
Chilean Winter Rainfall- Valdivian Forests
Bordered by Mesoamerica in the north, and to the east the Tropical Andes hotspots. Endemic fauna include bare-necked umbrella bird and the brightly- colored poison dart frogs, are characteristic of the region. The white-winged guan of Southern Ecuador and extreme northern Peru is seriously threatened with extinction. Urbanization, hunting (large birds and mammals), and deforestation, especially mangroves are threats. Ecuador's coastal forests are only 2 percent of their original area consequently species presence continue to decline. Tumbes-Chocó-Magdalena
Greatest biodiversity on Earth Contain about 1/6 of all plant spp. in <1% of earth's surface Species with unusual life histories e.g. Andean bromelilad 100 yrs to mature. The threatened yellow-eared parrot, yellow-tailed woolly monkey and spectacled bear are all endemic. Most species region for amphibians in the world (664 spp), 450 of which are on the 2004 IUCN Red List. A quarter of its habitat still remains, threats include: mining, timber extraction, oil exploration, and narcotics plantations, hydroelectric dams, cattle ranching and invasive species. Tropical Andes
Caucasus • Includes desert, savanna, arid woodland, and forests biomes • High levels of endemic plant species. • Mountainous landscapes have two species of highly threatened Caucasian turs (mountain goats). • Political turmoil provides lack of governmental regulation. • Forest clearing for fuel wood, illegal hunting and plant collecting are serious threats • The intact areas only really exist in the higher mountain regions • The plains experiencing the greatest levels of destruction.
Forms a natural Mountain barrier between the Mediterranean Basin and the dry plateaus of Western Asia. Consists of mountains and interior basins. Contain many centers of local endemism. Nearly 400 plant species are found only along the Anatolian Diagonal, a floristic line that crosses Inner Anatolia. Many of Turkey's 1,200 endemic species occur only to the immediate east or west of the divide. The hotspot includes four endemic and threatened species of viper. Irano-Anatolian
The flora include 22,500 endemic vascular plant species (4 x more in the rest of Europe. Includes many endemic reptile species. Threatened species are increasingly confined to fragmented and isolated patches due to tourism/resort developments The Mediterranean monk-seal, the barbary macaque and the Iberian lynx, which is Critically Endangered, are among the region's most threatened species. Mediterranean Basin
Comprising two of Asia's major mountain ranges, Known to early Persians as the "roof of the world." The hotspot's ecosystems include glaciers to deserts Include a highly threatened type of walnut-fruit forest, that contains ancestors of domestic fruit varieties (storehouse of genetic diversity). The hotspot is also home to a rich variety of ungulates, including the threatened argali wild sheep. Mountains of Central Asia
Cape Floristic Region • Evergreen fire-dependent shrublands characterize the landscape • One of the world's five Mediterranean hotspots. • Home to the greatest non-tropical concentration of higher plant species in the world, • Only hotspot that encompasses an entire floral kingdom, and holds five of South Africa's 12 endemic plant families and 160 endemic genera. • The geometric tortoise, the Cape sugar-bird, and a number of antelope species are characteristic species.
Small and fragmented, these forest high levels of biodiversity. 40,000 cultivated varieties of African violet, (US $100 million global trade) are derived from a few species of this hotspot Include a variety of primate species and three endemic and highly threatened monkey and two endemic bushbaby spp . The Tana River has two critically threatened and endemic primates, the Tana River red colobus and the Tana River mangabey. Agricultural expansion is the biggest threat. Poor soils, increasing populations, subsistence agriculture and commercial farming consume increasing amounts of natural habitat. Coastal Forests of Eastern Africa
This hotspot is distributed along the eastern edge of Africa, from Saudi Arabia in the north to Zimbabwe. Although fragmented, all patches have a similar flora. The Albertine Rift harbors more endemic mammals, birds, and amphib- ians than any other African region. A complex geological history has resulted in the formation of a series of unique freshwater lakes of immense fish diversity (e.g. 617 endemic fish species). Threats include agriculture, (bananas, beans, and tea) and the growing bushmeat “industry” Eastern Afromontane