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Cited by 1,876Conservation, Biodiversity, and Resource ManagementLand Use and Ecosystem ServicesAgriculture, Land Use, Rural Development

Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s

Open access
Gibbs, H. K., Ruesch, A. S., Achard, F., Clayton, M. K., Holmgren, P., Ramankutty, N., Foley, J. A.·2010·Proceedings of the National Academy of Sciences
DOI 10.1073/pnas.0910275107PMC PMC2944736
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Abstract

Global demand for agricultural products such as food, feed, and fuel is now a major driver of cropland and pasture expansion across much of the developing world. Whether these new agricultural lands replace forests, degraded forests, or grasslands greatly influences the environmental consequences of expansion. Although the general pattern is known, there still is no definitive quantification of these land-cover changes. Here we analyze the rich, pan-tropical database of classified Landsat scenes created by the Food and Agricultural Organization of the United Nations to examine pathways of agricultural expansion across the major tropical forest regions in the 1980s and 1990s and use this information to highlight the future land conversions that probably will be needed to meet mounting demand for agricultural products. Across the tropics, we find that between 1980 and 2000 more than 55% of new agricultural land came at the expense of intact forests, and another 28% came from disturbed forests. This study underscores the potential consequences of unabated agricultural expansion for forest conservation and carbon emissions.

Integrity signals

Registry

Crossref · 10.1073/pnas.0910275107

Cites

47 of 47 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 87 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    Shrubland conversion provided most of the remaining 8% of new agricultural land across the tropics.

    “Shrubland conversion provided most of the remaining 8% of expansion.”
    Quote in the paperNot a substantial claim
  • Findingown data
    § Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s

    Across the tropics, between 1980 and 2000, more than 55% of new agricultural land came from intact forests.

    “Across the tropics, we find that between 1980 and 2000 more than 55% of new agricultural land came at the expense of intact forests”
    • Also stated in: § Results · plain
      “Our results reveal that, overall, more than 55% of this new agricultural land came from intact forests (Fig. 2).”
    Quote in the paperSubstantial claim
  • Findingown data

    Across the tropics, between 1980 and 2000, 28% of new agricultural land came from disturbed forests.

    “An additional 28% of new agricultural land came from disturbed forests that previously had been affected by shifting cultivation, logging, fuel wood collection, or other forms of gradual degradation (Fig. 2).”
    Quote in the paperSubstantial claim
  • Findingreasoning

    Expansion in forest-rich regions of Latin America, Central Africa, and Southeast Asia relied predominantly on clearing intact forests for new agricultural land.

    “However, expansion in forest-rich regions of Latin America, Central Africa, and Southeast Asia relied predominately on clearing intact forests for new agricultural land.”
    Quote in the paperSubstantial claim
  • Findingcitation

    The greatest expansion of agricultural land in Latin America occurred for cattle pastures, which increased by about 35 million ha in South America and about 7 million ha in Central America.

    “The greatest expansion of agricultural land in Latin America occurred for cattle pastures, which increased by ∼35 million ha in South America and ∼7 million ha in Central America (14).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
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  • May combine two claims. 39
  • Classified as probably not a substantial claim. 20

  • May combine two claims.

    Findingcitation

    Cropland areas increased by about 5 million ha in South America between 1980 and 2000, more than double the increase in Central America.

    “Cropland areas increased by ∼5 million ha in South America between 1980 and 2000, more than double the increase in Central America.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [14]

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  • May combine two claims.

    Findingown data

    Most new agricultural land was established from intact and disturbed forests in Latin America, but strong geographic variation exists.

    “Most new agricultural land was established from intact and disturbed forests in Latin America, but strong geographic variation exists (Fig. 3).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    East Africa increased clearing of intact forests by about 20%, and conversion of disturbed forests decreased by the same amount.

    “East Africa increased clearing of intact forests by ∼20%, and conversion of disturbed forests decreased by the same amount.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    In West Africa, 20% less agricultural land came from intact forests, and 20% more came from disturbed forests in the 1990s than in the 1980s.

    “The opposite trend prevailed in West Africa: 20% less agricultural land came from intact forests, and 20% more came from disturbed forests in the 1990s than in the 1980s.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Although forest conversion dominated in the dense humid rainforest regions, shrubland became increasingly important in more sparsely forested areas.

    “For example, although forest conversion dominated in the dense humid rainforest regions, shrubland (i.e., cerrado) became increasingly important in more sparsely forested areas.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingcitation

    Sugarcane and soybeans are responsible for the majority of the increase in South America, whereas there were few changes in crop types across maize-dominated Central America.

    “Sugarcane and soybeans are responsible for the majority of the increase in South America, whereas there were few changes in crop types across maize-dominated Central America (14).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
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  • May combine two claims.

    Findingown data

    In Central Africa agricultural land was taken largely from intact forests, whereas East and West Africa used roughly equal amounts of intact and disturbed forests.

    “For example, in Central Africa agricultural land was taken largely from intact forests, whereas East and West Africa used roughly equal amounts of intact and disturbed forests.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    By the end of the 1990s, conversion of agricultural land accounted for nearly 70% of new plantations, indicating a reduction in forest clearing for this purpose.

    “By the end of the 1990s, conversion of agricultural land accounted for nearly 70% of new plantations, indicating a reduction in forest clearing for this purpose.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    During the 1980s, roughly half of new plantations were carved from forests; most of the remaining area came from conversion of agricultural land.

    “During the 1980s, roughly half of new plantations were carved from forests; most of the remaining area came from conversion of agricultural land.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingcitation

    Between 1980 and 2000 cropland area increased by about 50% in East Africa and by about 25% in West Africa.

    “However, between 1980 and 2000 cropland area increased by ∼50% in East Africa and by ∼25% in West Africa.”
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  • May combine two claims.

    Findingown data

    Shrublands and disturbed forests each provided a quarter of the new cropland in the 1980s but only 13% and 20%, respectively, by the 1990s.

    “Shrublands and disturbed forests each provided a quarter of the new cropland in the 1980s but only 13% and 20%, respectively, by the 1990s (Table S1).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Shrublands were converted primarily in regions with little forest cover and constituted a significant source of expanding agricultural land only in East Africa.

    “Shrublands were converted primarily in regions with little forest cover and constituted a significant source of expanding agricultural land only in East Africa (Fig. 4).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    The role of clearing intact forests in expanding agricultural area decreased from 73% to 67% in Central America, and that of disturbed forests had become more important by 2000.

    “Conversely, the role of clearing intact forests in expanding agricultural area decreased from 73% to 67% in Central America, and that of disturbed forests had become more important by 2000.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Southeast Asia relied on intact forests for nearly 60% of new agricultural land and on disturbed forests for more than 30%.

    “Southeast Asia relied on intact forests for nearly 60% of new agricultural land and on disturbed forests for more than 30%.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Southern Asia depended on disturbed forests for about 60% of new land and on intact forests for only 35%.

    “Southern Asia depended on disturbed forests for ∼60% of new land and on intact forests for only 35% (Fig. 5).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingcitation

    Southeast Asia is the only region where tree plantations occupy a large portion of total agricultural land, and the area of tree plantations increased from roughly 11 million ha to 17.4 million ha between 1980 and 2000.

    “Southeast Asia is the only region where tree plantations occupy a large portion of total agricultural land, and the area of tree plantations increased from roughly 11 million ha to 17.4 million ha between 1980 and 2000 (14).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [14]

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  • May combine two claims.

    Findingown data

    In Central Africa, 75% of new agricultural land came from forests in the 1980s, but this percentage decreased by about 10% during the 1990s as disturbed forests became more important sources.

    “In Central Africa, 75% of new agricultural land came from forests in the 1980s, but this percentage decreased by ∼10% during the 1990s as disturbed forests became more important sources (Table S1).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationcitation

    Agricultural expansion has been a major driver of deforestation and associated carbon emissions.

    “This finding confirms that agricultural expansion did not arise largely from previously cleared land and indeed has been a major driver of deforestation and the associated carbon emissions (31).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [31] source

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  • May combine two claims.

    Study design and conductcitation

    Continental and insular Southeast Asia were largely unaffected by the exclusion because they contain almost no area with less than 10% forest cover according to the FAO landcover map used to design the sampling scheme.

    “Continental and insular Southeast Asia were largely unaffected because they contain almost no area with <10% forest cover according to the FAO landcover map used to design the sampling scheme (34).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [34]

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  • May combine two claims.

    Premisecitation
    § Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s

    Not all agricultural expansion results in the loss of intact forests; shrublands, pasture, logged or regrowing forests, degraded land, and shifting cultivation fields are all sources for new permanent agriculture.

    “Agricultural expansion is a major driver of tropical deforestation (17)(18)(19)(20), but not all expansion results in the loss of intact forests: shrublands, pasture, logged or regrowing forests, degraded land, and shifting cultivation fields are all sources for new permanent agriculture (21)(22)(23).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [21] source

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning

    Land sources may have had intermediate uses within a decade, but the investigation captured only the two end points.

    “Land sources may have had intermediate uses within a decade, but our investigation captured only the two end points.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductcitation

    The majority of agricultural expansion in Brazil in the 1980s and 1990s was in the mid and northern regions of the country, indicating that the study captured most agricultural expansion in this region.

    “In addition, we evaluated the state-level agricultural expansion across Brazil and found that the majority of expansion occurring in the 1980s and 1990s was in the mid and northern regions of the country, indicating that we captured most agricultural expansion in this region (40).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [40]

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    A recent analysis of national agricultural and deforestation statistics for 1990-2005 by Pin Koh and Wilcove found that more than half the area of new plantations was carved from forests.

    “For example, a recent analysis of national agricultural and deforestation statistics for 1990-2005 by Pin Koh and Wilcove (22) found that more than half the area of new plantations was carved from forests.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [22] source

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data

    Because land-use and land-cover changes were assessed at 10-year intervals, the results describe decadal trends and can mask short-term, year-to-year variations in land use.

    “Because these land-use/land-cover changes were assessed at 10-y intervals, the results are intended to describe decadal trends in land-cover change and therefore can mask short-term, year-to-year variations in land use.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductnone given

    Parts of the cerrado in South America were excluded from the analysis, but most agricultural changes in this region were crop type or pasture substitution rather than increases in total agricultural land.

    “Parts of the cerrado in South America were excluded from the analysis, but most agricultural changes in this region were crop type or pasture substitution rather than increases in total agricultural land.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation
    § Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s

    The expansion of the global agricultural land area during the 1980s and 1990s occurred primarily in developing countries, where total agricultural land increased by 629 million ha while developed countries lost 335 million ha.

    “Indeed, the expansion of the global agricultural land area during the 1980s and 1990s occurred primarily in developing countries where total agricultural land (croplands, pastures, and temporary agriculture) increased by 629 million ha while developed countries lost 335 million ha (4,14).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductreasoning

    The FAO Landsat database provides major advances in data for assessing land sources for agricultural lands but does have inherent uncertainties and weaknesses.

    “The FAO Landsat database provides major advances in data for assessing land sources for agricultural lands but does have inherent uncertainties and weaknesses.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning

    This omission potentially could lead to a bias toward forests as the land sources in some cases.

    “This omission potentially could lead to a bias toward forests as the land sources in some cases.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductreasoning

    Excluding areas with less than 10% forest cover should not affect the results substantially because most expansion in agricultural area occurred in or near forest frontiers and very little occurred in dry zones.

    “However, in recent decades most expansion in agricultural area occurred in or near forest frontiers, and very little occurred in dry zones, so excluding areas with <10% forest cover should not affect the results substantially.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Study design and conductreasoning
    § Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s

    The FAO database provides a major advance by combining high-resolution analysis with a pan-tropical scale over a 20-year period.

    “Typically such detailed imagery processing is reserved for a single Landsat scene or small areas; by contrast, the FAO database provides a major advance by combining high-resolution analysis with a pan-tropical scale over a 20-y period.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S2 (checkable). May combine two claims.

    Interpretationcitation

    With policies such as REDD in place, farmers and large-scale producers would have greater incentives to improve management of previously cleared land and receive carbon payments for avoiding carbon release from further deforestation.

    “However, with policies such as REDD in place, farmers and large-scale producers would have greater incentives to improve management of previously cleared land and receive carbon payments for avoiding carbon release from further deforestation (45,46).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
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    • cites [46] source

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductcitation

    The FAO estimated sampling error for forest cover as ±3.6% for the pan-tropics, ±8.0% for Africa, ±4.7% for Latin America, and ±8.2% for Asia.

    “The FAO estimated sampling error for forest cover as ±3.6% for the pan-tropics, ±8.0% for Africa, ±4.7% for Latin America, and ±8.2% for Asia (34).”
    • Also stated in: § Methods · hedged
      “Sampling error, determined by the sampling design and variation within the population, was estimated for forest cover by the FAO as ±3.6% for the pantropics, ±8.0% for Africa, ±4.7% for Latin America, and ±8.2% for Asia (34).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [34]

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  • Classified as probably not a substantial claim.

    Study design and conductcitation

    Measurement error was assessed using a reliability ranking.

    “Measurement error was assessed using a reliability ranking.”
    • Also stated in: § Methods · plain
      “Measurement error, which is extremely difficult to quantify without field verification, was assessed using a reliability ranking, similar to fuzzy set theory (50), based on assumptions about the study areas and classification method used.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [50]

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  • May combine two claims.

    Study design and conductcitation
    § Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s

    The FAO survey includes all tropical forest types in wet, moist, and dry conditions and covers 63% of the total tropics and 87% of tropical forests.

    “The survey includes all tropical forest types in wet, moist, and dry conditions and covers 63% of the total tropics and 87% of tropical forests (34,35).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [34]

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data
    § Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s

    The data describe new agricultural expansion occurring within each decade and do not address expansion before 1980 or after 2000.

    “The data describe new agricultural expansion occurring within each decade and do not address expansion before 1980 or after 2000.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Study design and conductnone given
    § Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s

    FAO national statistics are of dubious accuracy for some regions but remain the only consistent source of information available across the tropics.

    “These statistics are of dubious accuracy for some regions but remain the only consistent source of information available across the tropics.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Premisenone given
    § Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s

    Most studies have focused on net expansion in agricultural area, and those that identify land sources often are limited to local and regional scales.

    “Most studies have focused on net expansion in agricultural area, and those that identify land sources often are limited to local and regional scales.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    Aggregating agriculture into broad categories may hide shifts among agricultural land types, such as between pasture and cropland or among crop types.

    “The aggregated agriculture categories also may mask shifts between agricultural land types, such as between pasture and cropland and different crop types.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Study design and conductcitation
    § Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s

    This method involves manual interpretation of both images at the same time, reducing errors associated with change detection and offering major advantages over single-period analysis or compilations of different sources of imagery.

    “This method involves manual interpretation of both images (historical and recent) at the same time, reducing errors associated with change detection (34) and offering major advantages over single-period analysis or compilations of different sources of imagery (17,33,35,36).”
    Quote in the paperSubstantial claim0 of 3 sources checked
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  • Probably not a substantial claim: may not pass S2 (checkable). May combine two claims.

    Study design and conductreasoning
    § Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s

    This remotely sensed database is distinct from the FAO country statistics and offers dramatic improvements over other information sources.

    “This remotely sensed database is distinct from the FAO country statistics and offers dramatic improvements over other information sources.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation

    A formal accuracy assessment of the results was not feasible because the study's historical nature and pan-tropical scale made field verification extremely difficult.

    “A formal accuracy assessment of the results was not feasible, given the historical nature of the study and the pan-tropical scale, which make field verification extremely difficult (17,(34)(35)(36).”
    • Also stated in: § Methods · plain
      “A formal accuracy assessment of the imagery was not feasible, given the historical nature and pan-tropical scale of the study (17,(34)(35)(36).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
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  • May combine two claims.

    Premisecitation

    Natural ecosystems provide locally and globally important services including storing much of Earth's biomass carbon, serving as habitats for endangered plants and animals, preserving major elements of the global hydrological cycle, and protecting massive watersheds.

    “These natural ecosystems provide locally and globally important services including storing of much of Earth's biomass carbon, serving as habitats for endangered plants and animals, preserving major elements of the global hydrological cycle, and protecting massive watersheds (34,44,47,48).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [34]

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    • cites [47] source

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  • May combine two claims.

    Premisecitation
    § Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s

    FAO national-level agriculture and forestry statistics are highly aggregated, have been described as unreliable, and do not provide the spatially detailed information needed for an accurate identification of land sources for new agricultural landscapes.

    “Others have postulated land sources from the United Nations Food and Agricultural Organization's (FAO) nationallevel agriculture and forestry statistics for broad regions (22,30), but these data are highly aggregated, have been described as unreliable (33), and do not provide the spatially detailed information needed for an accurate identification of land sources for new agricultural landscapes.”
    Quote in the paperSubstantial claim0 of 3 sources checked
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  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    Without REDD-like provisions, lucrative and increasingly large-scale agriculture will continue to clear forests in the path of expansion.

    “Without such provisions, lucrative and increasingly large-scale agriculture will continue to clear forests in the path of expansion.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Study design and conductcitation

    The tropical belt was organized into seven broad regions, each with broadly similar socioeconomic and ecological conditions expected to lead to common pathways of land-use change.

    “We organized the tropical belt into seven broad regions, each with broadly similar socioeconomic and ecological conditions expected to lead to common pathways of land-use change (20).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [20] source

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductcitation

    The FAO approach assures a high level of consistency and reduces errors associated with change detection.

    “The FAO approach assures a high level of consistency and reduces errors associated with change detection (34).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [34]

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  • May combine two claims.

    Study design and conductnone given

    The database consists of 117 randomly selected sample locations stratified by dry, moist, and humid tropical forest and covers 10% of the tropical forest belt.

    “This database consists of 117 randomly selected sample locations stratified by dry, moist, and humid tropical forest and covers 10% of the tropical forest belt (Fig. 1).”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Study design and conductown data

    Assumptions of normality were assessed by examining histograms of data distribution within regions and changes between decades; no obvious deviations from normality were found.

    “Assumptions of normality were assessed by examining histograms of data distribution within regions and changes between decades; no obvious deviations from normality were found.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Study design and conductcitation

    The survey included all tropical forest types and covered 63% of the entire tropics and 87% of tropical forests.

    “The survey included all tropical forest types and covered 63% of the entire tropics and 87% of tropical forests (34).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [34]

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49 of 49

  • The paper relies on this without support.

    Scientific descriptions of expanding agricultural lands and whether they arise from new deforestation or from previously cleared lands are largely absent and undocumented for the tropics as a whole.

    “Scientific descriptions of these expanding agricultural landsand whether they arise from new deforestation or from previously cleared lands-are surprisingly absent and remain largely undocumented for the tropics as a whole.”

  • The paper relies on this without support.

    Progress in environmental governance and policy decisions is hindered by sparse information on land sources for newly expanded croplands.

    “Progress in environmental governance and policy decisions (e.g., domestic and international standards for renewable fuel) is hindered by sparse information on land sources for newly expanded croplands.”

  • The paper relies on this without support.

    Worldwide demand for agricultural products is expected to increase by about 50% by 2050.

    “Worldwide demand for agricultural products is expected to increase by ∼50% by 2050, and evidence suggests that tropical countries will be called on to meet much of this demand.”

  • The paper relies on this without support.

    Tropical countries will be called on to meet much of the increased demand for agricultural products.

    “Worldwide demand for agricultural products is expected to increase by ∼50% by 2050, and evidence suggests that tropical countries will be called on to meet much of this demand.”
4 of 4

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Large-scale industrial agricultural production and commodity trade are increasingly linked to deforestation and forest degradation in the tropics.

    “Large-scale industrial agricultural production and commodity trade are increasingly linked to deforestation and forest degradation in the tropics (Gibbs et al., 2010;Henders et al., 2015;Curtis et al., 2018).”

    From Making deforestation risk visible. Discourses on bovine leather supply chain in Brazil (2020) · cites this paper as Gibbs et al., 2010

    The Conclusions link large-scale agro-industrial expansion and commodity markets to tropical deforestation, and the Results report that new agricultural land replaced both intact and disturbed forests. The paper does not establish that commodity trade or industrial agriculture causes forest degradation: it describes the disturbed forests as having been affected previously by logging, shifting cultivation, and other activities. (LLM, conf=0.82)

    Experimental — accuracy not yet measured

  • Changes to forest cover are particularly pronounced in tropical areas.

    “Changes to forest cover are particularly pronounced in tropical areas, where over 80% of new agricultural land was cleared from tropical rainforests between 1980 and 2000 and an estimated 2100 km2 of forests were lost per year between 2000 and 2012 [15, 16].”

    From Achieving global malaria eradication in changing landscapes (2021) · cites this paper as [15]

  • Agricultural expansion into natural ecosystems leads to significant losses of ecosystem services, such as habitat for biodiversity, carbon storage, flood mitigation, and soil and watershed protection.

    “Though inevitable, agricultural expansion into natural ecosystems leads to significant losses of ecosystem services, such as habitat necessary to maintain biodiversity, storage of carbon, flood mitigation, and soil and watershed protection, to cite a few (Foley et al., 2005;Gibbs et al., 2010;Lambin & Meyfroidt, 2011).”

    From Mapping the world's degraded lands (2015) · cites this paper as Gibbs et al., 2010

  • During the 1980s and 1990s, more than half of newly expanding agricultural areas in the tropics came at the expense of closed forests, with an additional third from disturbed forests.

    “For example, Gibbs et al. (2010) found that during the 1980s and 1990s more than half of newly expanding agricultural areas in the tropics came at the expense of closed forests, with an additional third from disturbed forests.”

    From Mapping the world's degraded lands (2015) · cites this paper as Gibbs et al. (2010)

  • No woody plantation land was abandoned.

    “No woody plantation land was abandoned.”

    From Mapping the world's degraded lands (2015) · cites this paper as Gibbs et al., 2010

Cites

Flagged first, then by citations

Research works printed but not linked: 7

  1. MW Rosegrant, S Msango, T Sulser, R Valmonte-Santos Biofuels and the Global Food Balance (International Food Policy Research Institute, Washington, DC, 2006).
  2. , ed SR Carpenter (Island Press, Washington, DC Ecosystems and Human Well-Being: Scenarios: Findings of the Scenarios Working Group of the Millennium Ecosystem Assessment, 2005).
  3. ; Food and Agriculture Organization of the United Nations Global Forest Resources Assessment 2000 (Food and Agriculture Organization, Rome, FAO Forestry Paper 140. (2000).
  4. ; Malaysian Oil Palm Council Palm Oil and the Environment (Malaysian Oil Palm Council, Kuala Lumpur, Malaysia, 2008).
  5. ; Food and Agriculture Organization of the United Nations Forest Resources Assessment 1990—Survey of Tropical Forest Cover and Study of Change Processes (Food and Agriculture Organization, Rome, FAO Forestry Paper 130. (1996).
  6. ; Food and Agriculture Organization of the United Nations FRA 2000: Pan-Tropical Survey of Forest Cover Changes, 1980–2000 (Food and Agriculture Organization, Rome, Forest Resources Assessment Working Paper 49. (2001).
  7. MF Goodchild Spatial Autocorrelation. Catmog 47 (Geo Books, Norwich, CT, 1986).

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Related

Authors
Gibbs, H. K., Ruesch, A. S., Achard, F., Clayton, M. K., Holmgren, P., Ramankutty, N., & Foley, J. A.
Affiliations
  • Stanford University (US)
  • University of Washington (US)
  • European Commission (BE)
  • University of Wisconsin–Madison (US)
  • Food and Agriculture Organization of the United Nations (IT)
  • McGill University (CA)
  • University of Minnesota (US)
ORCID
Venue
Proceedings of the National Academy of Sciences
Publisher
National Academy of Sciences
Published
2010-08-31
Volume
107
Issue
38
Pages
16732-16737
ISSN
  • 0027-8424 (ISSN-L)
  • 1091-6490
DOI
10.1073/pnas.0910275107
PMC
PMC2944736
OpenAlex
W2129920251
Cited by
1,876
References
47
Citations by year
2026: 82 · 2025: 91 · 2024: 87 · 2023: 137 · 2022: 163 · 2021: 145 · 2020: 166 · 2019: 186 · 2018: 114 · 2017: 149 · 2016: 122 · 2015: 110 · 2014: 94 · 2013: 87 · 2012: 73
FWCI
65.39
Type
journal article
Language
en
Open access
Locations
  • Proceedings of the National Academy of Sciences (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • Joint Research Centre (European Commission) (submittedVersion)
Funders
U.S. Department of Energy
Topics
  • Physical Sciences › Environmental Science › Global and Planetary Change › Conservation, Biodiversity, and Resource Management
  • Physical Sciences › Environmental Science › Global and Planetary Change › Land Use and Ecosystem Services
  • Life Sciences › Agricultural and Biological Sciences › General Agricultural and Biological Sciences › Agriculture, Land Use, Rural Development
Keywords
agricultural expansion, tropical forests, land conversion, cropland expansion, pasture expansion, forest loss, forest degradation, land cover change, Landsat imagery, biofuels, forest carbon emissions, forest conservation, 1980s-1990s
MeSH terms
Agriculture, Conservation of Natural Resources, Trees, Tropical Climate, United Nations, Databases, Factual, Crops, Agricultural, History, 20th Century, History, 21st Century

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-05.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-05.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

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