Editing IPCC:AR6/WGIII/Chapter-7 (section)

=== Box 7.1 | Case Study: Reducing the Impacts of Roads on Deforestation ===

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'''Summary'''

Rapidly expanding roads, particularly in tropical regions, are linked to forest loss, degradation, and fragmentation because the land becomes more generally accessible. Increase of land values of areas adjacent to roads also drives speculation and deforestation related to land tenure ( [[#Fearnside--2015|Fearnside 2015]] ). If poorly planned, infrastructure can facilitate fires, illegal mining, and wildlife poaching with consequences for GHG emissions and biodiversity conservation. However, some initiatives are providing new approaches for better planning and then limit environmental and societal impacts '''.'''

'''Background'''

Although the number and extent of protected areas has increased markedly in recent decades ( [[#Watson--2014|Watson et al. 2014]] ), many other indicators reveal that nature is in broad retreat. For example, the total area of intact wilderness is declining rapidly worldwide ( [[#Watson--2016|Watson et al. 2016]] ), 70% of the world’s forests are now less than 1 km from a forest edge ( [[#Haddad--2015|Haddad et al. 2015]] ), the extent of tropical forest fragmentation is accelerating exponentially ( [[#Taubert--2018|Taubert et al. 2018]] ). One of the most direct and immediate driver of deforestation and biodiversity decline is the dramatic expansion of roads and other transportation infrastructure ( [[#Laurance--2014a|Laurance et al. 2014a]] ; [[#Laurance--2017|Laurance and Arrea 2017]] ; [[#Alamgir--2017|Alamgir et al. 2017]] ).

'''Case description'''

From 2010 to 2050, the total length of paved roads is projected to increase by 25 million km ( [[#Dulac--2013|Dulac 2013]] ) including large infrastructure-expansion schemes in Asia ( [[#Laurance--2017|Laurance and Arrea 2017]] ; [[#Lechner--2018|Lechner et al. 2018]] ) and in South America ( [[#Laurance--2001|Laurance et al. 2001]] ; [[#Killeen--2007|Killeen 2007]] ), as well as widespread illegal or unplanned road building ( [[#Laurance--2009|Laurance et al. 2009]] ; [[#Barber--2014|Barber et al. 2014]] ). For example, in the Amazon, 95% of all deforestation occurs within 5.5 km of a road, and for every km of legal road there are nearly three km of illegal roads ( [[#Barber--2014|Barber et al. 2014]] ).

'''Interactions''' '''and limitations'''

More than any other proximate factor, the dramatic expansion of roads is determining the pace and patterns of habitat disruption and its impacts on biodiversity ( [[#Laurance--2009|Laurance et al. 2009]] ; [[#Laurance--2017|Laurance and Arrea 2017]] ). Much road expansion is poorly planned. Environmental Impact Assessments (EIAs) for roads and other infrastructure are typically too short term and superficial to detect rare species or assess long-term or indirect impacts of projects ( [[#Flyvbjerg--2009|Flyvbjerg 2009]] ; [[#Laurance--2017|Laurance and Arrea 2017]] ). Another limitation is the consideration of each project in isolation from other existing or planned developments ( [[#Laurance--2014b|Laurance et al. 2014b]] ). Hence, EIAs alone are inadequate for planning infrastructure projects and assessing their broader environmental, social, and financial impacts and risks ( [[#Laurance--2015a|Laurance et al. 2015a]] ; [[#Alamgir--2017|Alamgir et al. 2017]] , 2018).

'''Lessons'''

The large-scale, proactive land-use planning is an option for managing the development of modern infrastructure. Approaches such as the ‘Global Roadmap’ scheme ( [[#Laurance--2013|Laurance and Balmford 2013]] ; [[#Laurance--2014a|Laurance et al. 2014a]] ) Strategic Environmental Assessments ( [[#Fischer--2007|Fischer 2007]] ) can be used to evaluate the relative costs and benefits of infrastructure projects, and to spatially prioritise land uses to optimise human benefits while limited new infrastructure in areas of intact or critical habitats. For example, the Global Roadmap strategy has been used in parts of South-East Asia ( [[#Sloan--2018|Sloan et al. 2018]] ), Indochina ( [[#Balmford--2016|Balmford et al. 2016]] ), and sub-Saharan Africa ( [[#Laurance--2015b|Laurance et al. 2015b]] ) to devise land-use zoning that can help optimise the many risks and rewards of planned infrastructure projects.

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==== 7.3.1.3 Extractive Industry Development ====

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The extent and scale of mining is growing due to increased global demand ( [[#UNEP--2019|UNEP 2019]] ). Due to declining ore grades, more ore needs to be processed to meet demand, with extensive use of open cast mining. A low-carbon future may be more mineral intensive with, for example, clean energy technologies requiring greater inputs in comparison to fossil-fuel-based technologies ( [[#Hund--2020|Hund et al. 2020]] ). Mining presents cumulative environmental impacts, especially in intensively mined regions ( [[#UNEP--2019|UNEP 2019]] ). The impact of mining on deforestation varies considerably across minerals and countries. Mining causes significant changes to the environment, for example, through mining infrastructure establishment, soil erosion, urban expansion to support a growing workforce and development of mineral commodity supply chains ( [[#Sonter--2015|Sonter et al. 2015]] ). The increasing consumption of gold in developing countries, increased prices, and uncertainty in financial markets is identified as driving gold mining and associated deforestation in the Amazon region ( [[#Alvarez-Berrios--2015|Alvarez-Berrios and Mitchell Aide 2015]] ; [[#Dezécache--2017|Dezécache et al. 2017]] ; Asner and Tupayachi 2017; [[#Espejo--2018|Espejo et al. 2018]] ). The total estimated area of gold mining throughout the region increased by about 40% between 2012 and 2016 (Asner and Tupayachi 2017). In the Brazilian Amazon, mining significantly increased forest loss up to 70 km beyond mining lease boundaries, causing 11,670 km 2 of deforestation between 2005 and 2015, representing 9% of all Amazon forest loss during this time ( [[#Sonter--2015|Sonter et al. 2015]] ).

Mining is also an important driver of deforestation in African and Asian countries. In the Democratic Republic of Congo, where the second-largest area of tropical forest in the world occurs, mining-related deforestation exacerbated by violent conflict ( [[#Butsic--2015|Butsic et al. 2015]] ). In India, mining has contributed to deforestation at a district level, with coal, iron and limestone having had the most adverse impact on forest area loss ( [[#Ranjan--2019|Ranjan 2019]] ). Gold mining is also identified as a driver of deforestation in Myanmar ( [[#Papworth--2017|Papworth et al. 2017]] ).

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==== 7.3.1.4 Fire Regime Changes ====

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Wildland fires account for approximately 70% of the global biomass burned annually ( [[#van%20der%20Werf--2017|van der Werf et al. 2017]] ) and constitute a large global source of atmospheric trace gases and aerosols ( [[#Gunsch--2018|Gunsch et al. 2018]] ) (IPCC WGI AR6). Although fires are part of the natural system, the frequency of fires has increased in many areas, exacerbated by decreases in precipitation, including in many regions with humid and temperate forests that rarely experience large-scale fires naturally. Natural and human-ignited fires affect all major biomes, from peatlands through shrublands to tropical and boreal forests, altering ecosystem structure and functioning ( [[#Argañaraz--2015|Argañaraz et al. 2015]] ; [[#Nunes--2016|Nunes et al. 2016]] ; [[#Remy--2017|Remy et al. 2017]] ; [[#Mancini--2018|Mancini et al. 2018]] ; [[#Aragão--2018|Aragão et al. 2018]] ; [[#Engel--2019|Engel et al. 2019]] ; [[#Rodríguez%20Vásquez--2021|Rodríguez Vásquez et al. 2021]] ). However, the degree of incidence and regional trends are quite different and a study over 14 years indicated, on average, the largest fires in Australia, boreal North America and Northern Hemisphere Africa ( [[#Andela--2019|Andela et al. 2019]] ). More than half of the terrestrial surface of the Earth has fire regimes outside the range of natural variability, with changes in fire frequency and intensity posing major challenges for land restoration and recovery (Barger et al. 2018). In some ecosystems, fire prevention might lead to accumulation of large fuel loads that enable wildfires ( [[#Moreira--2020a|Moreira et al. 2020a]] ).

About 98 Mha of forest and savannahs are estimated to have been affected by fire in 2015 ( [[#FAO%20and%20UNEP--2020|FAO and]] [[#UNEP--2020|UNEP 2020]] ). Fire is a prevalent forest disturbance in the tropics where about 4% of the total forest and savannah area in that year was burned and more than two-thirds of the total area affected was in Africa and South America; mostly open savanna types ( [[#FAO%20and%20UNEP--2020|FAO and]] [[#UNEP--2020|UNEP 2020]] ). Fires have many different causes, with land clearing for agriculture the primary driver in tropical regions, for example, clearance for industrial oil-palm and paper-pulp plantations in Indonesia ( [[#Chisholm--2016|Chisholm et al. 2016]] ), or for pastures in the Amazon ( [[#Barlow--2020|Barlow et al. 2020]] ). Other socio-economic factors are also associated with wildfire regimes such as land-use conflict and socio-demographic aspects ( [[#Nunes--2016|Nunes et al. 2016]] ; [[#Mancini--2018|Mancini et al. 2018]] ). Wildfire regimes are also changing by the influence of climate change, with wildfire seasons becoming longer, wildfire average size increases in many areas and wildfires occurring in areas where they did not occur before ( [[#Jolly--2015|Jolly et al. 2015]] ; [[#Artés--2019|Artés et al. 2019]] ). Human influence has likely increased fire weather in some regions of all inhabited continents (IPCC AR6 WGI Technical Summary) and, in the last years, fire seasons of unprecedented magnitude occurred in diverse regions as California ( [[#Goss--2020|Goss et al. 2020]] ), the Mediterranean basin ( [[#Ruffault--2020|Ruffault et al. 2020]] ), Canada ( [[#Kirchmeier‐Young--2019|Kirchmeier‐Young et al. 2019]] ) with unprecedented fires in British Columbia in 2021, the Arctic and Siberia ( [[#McCarty--2020|McCarty et al. 2020]] ), Brazilian Amazon ( [[#Silva--2021|Silva et al. 2021]] ) and Pantanal ( [[#Leal%20Filho--2021|Leal Filho et al. 2021]] ), Chile ( [[#Bowman--2019|Bowman et al. 2019]] ) and Australia ( [[#Ward--2020|Ward et al. 2020]] ; [[#Gallagher--2021|Gallagher et al. 2021]] ). Lightning plays an important role in the ignition of wildfires, with the incidence of lightning igniting wildfires predicted to increase with rises in global average air temperature ( [[#Worden--2017|Worden et al. 2017]] ).

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==== 7.3.1.5 Logging and Fuelwood Harvest ====

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The area of forest designated for production has been relatively stable since 1990. Considering forest uses, about 30% (1.2 billion ha) of all forests is used primarily for production (wood and non-wood forest products), about 10% (424 Mha) is designated for biodiversity conservation, 398 Mha for the protection of soil and water, and 186 Mha is allocated for social services (recreation, tourism, education research and the conservation of cultural and spiritual sites) ( [[#FAO%20and%20UNEP--2020|FAO and]] [[#UNEP--2020|UNEP 2020]] ). While the rate of increase in the area of forest allocated primarily for biodiversity conservation has slowed in the last ten years, the rate of increase in the area of forest allocated for soil and water protection has grown since 1990, and notably in the last ten years. Global wood harvest (including from forests, other wooded land and trees outside forests) was estimated to be almost 4.0 billion m 3 in 2018 (considering both industrial roundwood and fuelwood) (FAO, 2019). Overall, wood removals are increasing globally as demand for, and the consumption of wood products grows annually by 1% in line with growing populations and incomes with this trend expected to continue in coming decades. When done in a sustainable way, more regrowth will occur and is stimulated by management, resulting in a net sink. However illegal and unsustainable logging (i.e., harvesting of timber in contravention of the laws and regulations of the country of harvest) is a global problem with significant negative economic (e.g., lost revenue), environmental (e.g., deforestation, forest degradation, GHG emissions and biodiversity losses) and social impact (e.g., conflicts over land and resources, disempowerment of local and indigenous communities) ( [[#World%20Bank--2019|World Bank 2019]] ). Many countries around the world have introduced regulations for the international trade of forest products to reduce illegal logging, with significant and positive impacts ( [[#Guan--2018|Guan et al. 2018]] ).

Over-extraction of wood for timber and fuelwood is identified as an important driver of mangrove deforestation and degradation ( [[#Bhattarai--2011|Bhattarai 2011]] ; [[#Ajonina--2014|Ajonina et al. 2014]] ; [[#Webb--2014|Webb et al. 2014]] ; [[#Giri--2015|Giri et al. 2015]] ; [[#Thomas--2017|Thomas et al. 2017]] ; Fauzi et al. 2019). Unsustainable selective logging and over-extraction of wood is a substantial form of forest and mangrove degradation in many tropical and developing countries, with emissions associated with the extracted wood, incidental damage to the surrounding forest and from logging infrastructure ( [[#Bhattarai--2011|Bhattarai 2011]] ; [[#Ajonina--2014|Ajonina et al. 2014]] ; [[#Webb--2014|Webb et al. 2014]] ; [[#Pearson--2014|Pearson et al. 2014]] , [[#Giri--2015|Giri et al. 2015]] ; [[#Thomas--2017|Thomas et al. 2017]] ; Fauzi et al. 2019). Traditional fuelwood and charcoal continue to represent a dominant share of total wood consumption in low-income countries (Barger et al. 2018). Regionally, the percentage of total wood harvested used as fuelwood varies from 90% in Africa, 62% in Asia, 50% in South America to less than 20% in Europe, North America and Oceania. Under current projections, efforts to intensify wood production in plantation forests, together with increases in fuel-use efficiency and electrification, are suggested to only partly alleviate the pressure on native forests (Barger et al. 2018). Nevertheless, the area of forest under management plans has increased in all regions since 2000 by 233 Mha ( [[#FAO--2020e|FAO 2020e]] ). In regions representing the majority of industrial wood production, forests certified under sustainable forest management programmes accounted for 51% of total managed forest area in 2017, an increase from 11% in 2000 ( [[#ICFPA--2021|ICFPA 2021]] ).

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