Threats and Strategies for Global Biodiversity Conservation

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ecological restoration or community protection. Socialtransmigration schemes, whereby villages or communitiesare moved from one location to another for rural developmentpurposes, can also pose a threat to fire regimes.Often, transplanted communities lack familiarity withtheir new environment and the land and fire uses thatcan be sustained there. Combined with a lack of understandingof local fire ecology, this can lead to a loss of thenatural fire regime. For instance, colonization of thetemperate forests of Mexico’s Sierra Madre Occidentalled to a drastic decrease in fire frequency in the early tomid 1900s (Heyerdahl and Alvarado 2003). More recently,extensive colonization of the Brazilian Amazon forestcreated a massive fire problem that is threatening thesustainability of one of the most biodiverse biomes(Cochrane 2002).Livestock Farming, Ranching and AgricultureModern and traditional grazing and ranching practices arean expanding threat to biodiversity worldwide, particularlywhere food security is a global priority. These practiceshave altered fire regimes across the vast majority of majorhabitat types worldwide (12 of 14), and affect almost 25%of all terrestrial ecoregions assessed. In fire-dependentecosystems, such as temperate, tropical and subtropicalgrasslands, savannas, and shrublands, livestock farmingand ranching can reduce fuel levels, connectivity andpatchiness, and thus the ability of an ecosystem to carryfire on a large scale, or can cause too much fire dueto annual firing of grasses to rejuvenate them.Agriculture is a top global source of threat to biodiversityoverall, and alters fire regimes in at least 30% of allecoregions worldwide (and 12 of 14 major habitat types).Major habitat types particularly at risk include tropical andsubtropical dry broadleaf forests; tropical and subtropicalgrasslands, savannas and shrublands; tropical and subtropicalmoist broadleaf forests; and flooded grasslands andsavannas. In tropical areas, large areas of peat swampforest have been converted to agricultural land. Thisresults in altered drainage patterns leading to degradedpeat swamp forests and high fire risk.Slash and burn shifting agriculture and ranching are predominantpractices in many parts of the developing world,and a way of life for many people. In fire-sensitive systems,such as tropical and subtropical dry and moist broadleafforests, ecologically-inappropriate fire use for land clearing,forage management, and shifting agriculture leads to directconversion of habitat. When fires escape, adjacent forestsare also impacted. The environmental degradation thatresults from poor fire management practices can trap localpeople in a “poverty cycle,” where poverty leads to environmentaldegradation, which then reduces the capacity ofecosystems to sustain human livelihoods.Fire and Fire SuppressionFire regimes in almost all major habitat types (13 of 14)are threatened by ecologically-inappropriate humanintroduction of fire or fire suppression. Over 20% of allterrestrial ecoregions assessed experience altered fire regimesthrough direct fire suppression or human-caused ignitionsoutside the range of natural variation. Across fire-dependenthabitats, fire suppression to protect human values not onlydirectly alters fire regimes, but can also lead to furtherdegradation from increased forest and shrub densities, lossof fire-adapted species, increases in fire-sensitive species,and uncharacteristic fire behavior when fires escapesuppression forces.ThreatLivestock Farming and RanchingEnergy Production and MiningFire and Fire SuppressionRural and Urban DevelopmentAgricultureConflicts with Traditional Fire UseClimate ChangeLogging and Wood HarvestingTransportation InfrastructureInvasive SpeciesRecreational ActivitiesGathering Terrestrial PlantsDams and Water Management UseWood and Pulp PlantationsRealmAustralasia Indo-Malay Nearctic Neotropic10Table 1. Top sources of threats to restoring andmaintaining the ecological role of fire by realmassessed during realm-level expert workshopsJanuary-July 2006.
A United Nations analysis of national fire policies in 1998concluded that fire mitigation policies were generallyweak, and were rarely based on reliable data of forest fireextent, causes or risks (ECE/FAO 1998). Inadequateforest management policies are often incompatible withbiodiversity conservation, particularly policies aimed attotal fire exclusion in fire-dependent ecosystems, whichcan lead to fuel accumulation and catastrophic fire outbreaks(Hassan et al. 2005). Public policies that ban orseverely limit burning can also put people at risk ofbreaking laws when their intentions are to maintainecological processes and traditional cultures. Intentionaland unintentional human-caused ignitions, where there islittle fire management capacity to prevent or suppress them,degrade the ecological sustainability of fire-sensitive andfire-independent ecosystems by increasing their vulnerabilityto invasive species and future fires.Resource ExtractionFire regimes in more than 13% of all terrestrial ecoregionsassessed (and 12 of 14 major habitat types) are consideredto be altered by energy production and mining. Energyproduction and mining is an expanding threat worldwideas development increases and global energy markets shift.Transportation infrastructures for energy and miningoperations—roads, powerlines, pipelines, railroads—act asa conduit for both invasive species and increased humancausedfire ignitions in fire-dependent, fire-independentand fire-sensitive ecosystems. The alteration of fire regimesat this “development frontier” has exponentially greaterconsequences for biodiversity in fire-sensitive systems,where the area of fire spread and deforestation can bemuch greater than the area impacted by the energy andmining operations themselves.In addition, fire regimes in over 3% of all terrestrial ecoregionsassessed (and seven of 14 major habitat types) areconsidered to be altered by logging and wood harvesting.Logging and wood harvesting are of particular concernrelative to their alteration of fire regimes in the Indo-Malay, Nearctic and Neotropic realms (Table 1). Loggingand wood harvesting can be a direct source of threatthrough human-caused ignitions, or through the indirecteffect of altering fuels and moisture conditions thatencourage “too much” fire. “Too little” fire, in terms of numberand severity, may also result from fuelwood collectionfor domestic use by rural communities. Modification offuelbed structure can also reduce crown fires where theyare part of the natural regime. Forest certification strategiesthat aim to ensure ecologically sustainable logging andwood harvesting practices can be greatly improved byincluding the need for fire in fire-dependent ecosystems,and need for fire suppression, mitigation and prevention infire-sensitive and fire-independent ecosystems.Logging alters fire regimes in forests around the globe when it createsforest structures or fuel loads that are inconsistent with the natural fireregime. The Nature Conservancy and partners are working in this forestin Chiapas, Mexico to improve management practices and mitigate theeffects of logging on fire regimes. © Mark GodfreyClimate ChangeFire experts identified climate change as a potential causeof fire-related threats to biodiversity in 4% of all ecoregionsworldwide and 12 of 14 major habitat types. Regionalexpert workshops, however, revealed a range in judgmentof the relative importance of climate change compared toother sources; the actual importance of climate change inaltering fire regimes may likely exceed the expert ranking.Generally, in fire-dependent systems where the ecologicallyappropriatefire regime is intact, there should be no netloss of stored carbon because the biomass that burnsregrows over the life of the fire cycle. However, climatechange is increasing fire frequency and extent by alteringthe key factors that control fire: temperature, precipitation,humidity, wind, ignition, biomass, dead organic matter,vegetation species composition and structure, and soilmoisture (IPCC 2001). These changes threaten properecosystem function and the provision of ecosystem services(Hassan et al. 2005, IPCC 2001, Turner et al. 1997).Warmer temperatures, decreased precipitation over land,increased convective activity, increases in standing biomassdue to CO2 fertilization, increased fuels from dyingvegetation, and large-scale vegetation shifts comprisethe most significant mechanisms through which globalwarming increases fire at the global scale. In the case offires larger than 400 hectares in mid-altitude, federallymanagedconifer forests of the western U.S., an increasein spring and summer temperatures of 1˚C since 1970,earlier snowmelt, and longer summers have increased firefrequency 400% and burned area 650% in the period 1970-2003 (Westerling et al. 2006). The low level of humanactivity or fire exclusion in those forests, however, impliesthat climate change may cause different impacts in areas ofintense human intervention.11
Page 2 and 3: Citation:(see inside back cover for
Page 4 and 5: Mopping-up after a prescribed burn
Page 6 and 7: This area in Sepang, Selangor, Mala
Page 8 and 9: There are a variety of ways invasiv
Page 10 and 11: In order to craft effective strateg
Page 12 and 13: Box 4. Global Fire Assessment WebGI
Page 14 and 15: very degraded—often repeat themse
Page 18 and 19: Cattle grazing and browsing in Mall
Page 20 and 21: eptiles. However, fire from these g
Page 22 and 23: Box 5. Needs for Integrated Fire Ma
Page 24 and 25: Notes:1. Ecoregions share similar e
Page 26 and 27: ReferencesOlson, D.M., E. Dinerstei
Page 28: The mission of The Nature Conservan

Threats and Strategies for Global Biodiversity Conservation

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