Where have all the forests gone? Quantifying pantropical deforestation drivers

Deforestation across the tropics continues to be a major source of greenhouse gas emissions and the largest threat to biodiversity on land. With strengthened commitments to reduce deforestation from countries and companies alike, it is crucial that renewed investments for reducing deforestation be guided by a sound understanding of what drives deforestation. This thesis gives a comprehensive picture of the amount of deforestation and concomitant carbon emissions driven by the expansion of agricultural commodities across the tropics and its link to international trade. The included papers show that pasture and a handful of crops drive a large share of the deforestation resulting in the expansion of productive agriculture. The main demand for these commodities is domestic consumption; even so, imports of food commodities associated with deforestation can still constitute a large part of the consumer countries’ carbon emissions due to consumption (e.g., in the EU). This thesis contributes empirical evidence relating to forest transition theories by showing that many countries with increasing forest cover tend to import products associated with deforestation elsewhere, thereby offsetting around one-third of their forest gains. The thesis also introduces a conceptual distinction between two categories of agriculture-driven deforestation, based on whether it results in productive agricultural land or not. Though almost all deforestation is agriculture-driven, one-third to one-half of agriculture-driven deforestation occurs without the expansion of productive agricultural land. Instead, it may be due to several potential mechanisms, such as land speculation, tenure issues, or fires. Put together, these results indicate that it is crucial that policies to curb deforestation go beyond focusing only on trade in specific commodities, to help foster concerted action on rural development, territorial governance, and land-use planning. This thesis also highlights key evidence gaps on the links between deforestation and agriculture: (i) the attribution of deforestation to specific commodities currently often relies on coarse or outdated data, (ii) there is a need for improved data on deforestation trends, and (iii) our understanding of deforestation drivers is systematically poorer for dry forests and Africa

Felling Forests from Afar: Quantifying Deforestation Driven by Agricultural Expansion and International Trade

Deforestation is a major source of human-caused greenhouse gas emissions and the largest threat to terrestrial biodiversity. Most forest loss is due to the expansion of agricultural land use increasingly driven by international demand for food, fuel and fibre. However, there is still limited understanding of the extent to which different agricultural commodities are contributing to deforestation. It has therefore also been difficult to evaluate the role of international trade in driving deforestation. This dissertation aims at quantifying the agricultural drivers of tropical deforestation (Papers I and II) and the associated carbon emissions (Paper III). It further assesses the role of international trade, by following the agricultural commodities with embodied deforestation through international supply chains using trade models (Papers II and III). The results show that a few commodity types, primarily cattle meat and oilseed products, account for a large part of tropical deforestation. Much (26–39%) of the embodied deforestation and concomitant emissions were found to be associated with international demand (from products and services). Looking closer at the countries that import embodied deforestation, Paper II finds that many countries that are increasing their forest cover at home, import products associated with deforestation elsewhere, thereby offsetting about a third of their forest gains. Paper III finds that imports of embodied deforestation emissions for many developed countries are similar in size to their national agricultural emissions amounting, e.g., for the EU, to around 15% of the carbon footprint of an average diet. Put together, the results add to the evidence that combating deforestation can benefit from complementing domestic policies with measures that target international demand. The results also indicate that tackling deforestation and its associated impacts at the global level is probably even more challenging than at the national level, although international trade can also provide efficiency gains by optimising land use globally

Deforestation displaced: trade in forest-risk commodities and the prospects for a global forest transition

While many developed countries are increasing their forest cover, deforestation is still rife in the tropics and subtropics. With international trade in forest-risk commodities on the rise, it is becoming increasingly important to consider between-country trade linkages in assessing the drivers of-and possible connections between-forest loss and gain across countries. Previous studies have shown that countries that have undergone a forest transition (and are now increasing their forest cover) tend to displace land use outside their borders. However, lack of comprehensive data on deforestation drivers imply that it has not been possible to ascertain whether this has accelerated forest loss in sourcing countries. To remedy this, we present a land-balance model that quantifies deforestation embodied in production of agricultural and forestry commodities at country level across the tropics and subtropics, subsequently tracing embodied deforestation to countries of apparent consumption using a physical, country-to-country trade model. We find that in the period 2005-2013,62% (5.5 Mha yr(-1)) of forest loss could be attributed to expanding commercial cropland, pastures and tree plantations. The commodity groups most commonly associated with deforestation were cattle meat, forestry products, oil palm, cereals and soybeans, though variation between countries and regions was large. Alarge (26%) and slightly increasing share of deforestation was attributed to international demand, the bulk of which (87%) was exported to countries that either exhibit decreasing deforestation rates or increasing forest cover (late-or post-forest transition countries), particularly in Europe and Asia (China, India, and Russia). About a third of the net forest gains in post-forest transition countries was in this way offset by imports of commodities causing deforestation elsewhere, suggesting that achieving a global forest transition will be substantially more challenging than achieving national or regional ones

Disentangling the numbers behind agriculture-driven tropical deforestation

Tropical deforestation continues at alarming rates with profound impacts on ecosystems, climate, and livelihoods, prompting renewed commitments to halt its continuation. Although it is well established that agriculture is a dominant driver of deforestation, rates and mechanisms remain disputed and often lack a clear evidence base. We synthesize the best available pantropical evidence to provide clarity on how agriculture drives deforestation. Although most (90 to 99%) deforestation across the tropics 2011 to 2015 was driven by agriculture, only 45 to 65% of deforested land became productive agriculture within a few years. Therefore, ending deforestation likely requires combining measures to create deforestation-free supply chains with landscape governance interventions. We highlight key remaining evidence gaps including deforestation trends, commodity-specific land-use dynamics, and data from tropical dry forests and forests across Africa

Combining global land cover datasets to quantify agricultural expansion into forests in Latin America: Limitations and challenges

<div><p>While we know that deforestation in the tropics is increasingly driven by commercial agriculture, most tropical countries still lack recent and spatially-explicit assessments of the relative importance of pasture and cropland expansion in causing forest loss. Here we present a spatially explicit quantification of the extent to which cultivated land and grassland expanded at the expense of forests across Latin America in 2001–2011, by combining two “state-of-the-art” global datasets (Global Forest Change forest loss and GlobeLand30-2010 land cover). We further evaluate some of the limitations and challenges in doing this. We find that this approach does capture some of the major patterns of land cover following deforestation, with GlobeLand30-2010’s Grassland class (which we interpret as pasture) being the most common land cover replacing forests across Latin America. However, our analysis also reveals some major limitations to combining these land cover datasets for quantifying pasture and cropland expansion into forest. First, a simple one-to-one translation between GlobeLand30-2010’s Cultivated land and Grassland classes into cropland and pasture respectively, should not be made without caution, as GlobeLand30-2010 defines its Cultivated land to include some pastures. Comparisons with the TerraClass dataset over the Brazilian Amazon and with previous literature indicates that Cultivated land in GlobeLand30-2010 includes notable amounts of pasture and other vegetation (e.g. in Paraguay and the Brazilian Amazon). This further suggests that the approach taken here generally leads to an underestimation (of up to ~60%) of the role of pasture in replacing forest. Second, a large share (~33%) of the Global Forest Change forest loss is found to still be forest according to GlobeLand30-2010 and our analysis suggests that the accuracy of the combined datasets, especially for areas with heterogeneous land cover and/or small-scale forest loss, is still too poor for deriving accurate quantifications of land cover following forest loss.</p></div

Forest loss 2001–2011 and post-loss land cover per country.

<p>(A) Proportion of GlobeLand-30-2010 land cover types following GFC forest loss. The proportions are based on forest loss for part of the period only, as post-loss land cover can only be assessed for areas with forest loss prior to the date of the land cover data. (B) Tree cover loss 2001–2011 per country, detected by GFC.</p

TerraClass 2010 and GlobeLand30-2010 land cover/use classes (Mha) following GFC forest loss.

<p>TerraClass 2010 and GlobeLand30-2010 land cover/use classes (Mha) following GFC forest loss.</p

Annual GFC (G) and PRODES (P) forest loss in the Brazilian Legal Amazon 2001–2014.

<p>Grey shows where both datasets report loss at some point during the time period.</p

Definitions for the key land cover / land use (change) classes in the four datasets used.

<p>Definitions for the key land cover / land use (change) classes in the four datasets used.</p

Forest loss 2001–2011 and post-loss land cover per biome.

<p>(A) Proportion of GlobeLand-30 land-2010 cover types following GFC forest loss. (B) Tree cover loss 2001–2011 per biome, detected by GFC (only the biomes with the most forest loss are shown). Biome boundaries from Terrestrial Ecoregions of the World [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0181202#pone.0181202.ref054" target="_blank">54</a>].</p