Regional Deforestation Research Articles

Two decades of accelerated deforestation in Peruvian forests: a national and regional analysis (2000–2020)

The global tree cover has kept reducing in the last two decades, mainly in tropical forests, despite the global efforts to conserve biodiversity and the ecosystem services that provides. Considering South America is the region that had the highest rate of net forest loss (2000–2020), it is crucial to understand the deforestation dynamics of each country and their regions for the evaluation of effective national conservation actions. Here, we carried out a spatiotemporal analysis of the deforestation rates from 2000 to 2020 on a national and regional scale, including the forest loss inside protected areas, in Peru. It was found that Peru lost 3.4 million ha of forest between 2000 and 2020, mainly in the Not Flooded Rainforest region. National deforestation rates accelerated, while within protected areas rates showed a very small increase. Regional deforestation rates followed the national pattern with one exception—the Coast region. Our results evidence the success of the national conservation strategy based on protected areas to avoid deforestation in all regions, except in the Andean. Moreover, the increment in deforestation rates is aligned with the growth in road infrastructure; increments in anthropic activities; and the more frequent and intense natural extreme events that vary according to the region. Therefore, it is urgent to differentiate the drivers of deforestation that operate at the national versus the regional scale, consider the inclusion of all forest types in the monitoring system, and the strengthening of policies related to land use change at all scales.

Sub‐Grid Representation of Vegetation Cover in Land Surface Schemes Improves the Modeling of How Climate Responds to Deforestation

AbstractUnderstanding the regional climate response to land cover change requires a realistic sub‐grid representation of vegetation cover in the land surface scheme (LSS) of climate models. The Community Land Model (CLM) is considered one of the most advanced LSSs; however, when coupled with the Weather Research and Forecasting (WRF) model, the tiling vegetation cover approach was deactivated. Here, we reactivated the theoretical sub‐grid vegetation cover representation in WRF‐CLM and applied it to assess the impacts of deforestation on regional climate in the Southeast Asian Massif region. We found that CLM‐tiling performs more accurate simulations of surface air temperature and precipitation compared to other LSSs using the in situ observations. Importantly, CLM‐tiling successfully captures the theoretical sensitivity of evapotranspiration (ET) and temperature to sub‐grid deforestation, aligning with Noah‐mosaic, and it substantially improves the spatial pattern responses of simulated ET and temperature to regional deforestation.

Protected Areas Conserved Forests from Fire and Deforestation in Vietnam’s Central Highlands from 2001 to 2020

As a tropical nation with ~40% forested land area and 290 protected areas in the Indo-Burma Biodiversity Hotspot, Vietnam holds an important part of global forests. Despite a complex history of multiple colonial rules, war, rapid economic development and societal growth, Vietnam was one of a few Southeast Asian countries to reverse deforestation trends and sustain net forest cover gain since the 1990s. However, a considerable amount of Vietnam’s forest gain has been from plantation forestry, as Vietnam’s policies have promoted economic development. In the Central Highlands region of Vietnam, widespread forest degradation and deforestation has occurred recently in some areas due to plantation forestry and other factors, including fire-linked deforestation, but protected areas here have been largely effective in their conservation goals. We studied deforestation, wildfires, and the contribution of fire-linked deforestation from 2001 to 2020 in an area near the Da Lat Plateau of the Central Highlands of Vietnam. We stratified our study area to distinguish legally protected areas and those in the surrounding landscape matrix without formal protection. Using satellite-derived data, we investigated four questions: (1) Have regional deforestation trends continued in parts of the Central Highlands from 2001 to 2020? (2) Based on remotely sensed fire detections, how has fire affected the Central Highlands and what proportion of deforestation is spatiotemporally linked to fire? (3) Were annual deforestation and burned area lower in protected areas relative to the surrounding land matrix? (4) Was the proportion of fire-linked deforestation lower in protected areas than in the matrix? To answer these questions, we integrated the Global Forest Change and FIRED VIETNAM datasets. We found that 3794 fires burned 8.7% of the total study area and 13.6% of the area became deforested between 2001 and 2020. While nearly half of fires were linked to deforestation, fire-linked deforestation accounted for only a small part of forest loss. Across the entire study area, 54% of fire-linked deforestation occurred in natural forests and 46% was in plantation forests. Fire ignitions in the study area were strongly linked to the regional dry season, November to March, and instrumental climate data from 1971 to 2020 showed statistically significant increasing trends in minimum, mean, and maximum temperatures. However, the total area burned did not have a significant increasing trend. Regional trends in deforestation continued in Vietnam’s Central Highlands from 2001 to 2020, and nearly half of all detected fires can be spatially and temporally linked to forest loss. However, protected areas in the region effectively conserved forests relative to the surrounding landscape.

Human impacts outpace natural processes in the Amazon

Amazonian environments are being degraded by modern industrial and agricultural activities at a pace far above anything previously known, imperiling its vast biodiversity reserves and globally important ecosystem services. The most substantial threats come from regional deforestation, because of export market demands, and global climate change. The Amazon is currently perched to transition rapidly from a largely forested to a nonforested landscape. These changes are happening much too rapidly for Amazonian species, peoples, and ecosystems to respond adaptively. Policies to prevent the worst outcomes are known and must be enacted immediately. We now need political will and leadership to act on this information. To fail the Amazon is to fail the biosphere, and we fail to act at our peril.

Impacts of land cover changes and global warming on climate in Colombia during ENSO events

Colombia is highly vulnerable to climate change which may be intensified due to the climatic effects of regional deforestation. Here, we quantify the impact of historical (1900–2011) land cover changes (LCC) and of global warming during ENSO events (CC) on precipitation, temperature and surface energy balance components by running the Weather Research and Forecasting model WRF v3.9 at 10 km resolution. We find that historical anthropogenic CC causes a mean temperature increase of 0.77 ± 0.02 °C in Colombia, which is more pronounced in high altitudes. Precipitation is enhanced by 0.98 ± 0.30 mm/day (+ 9%), particularly over forested areas and reduced at the Pacific coast. LCC imply a reduction of precipitation particularly above the Andes (− 0.48 ± 0.10 mm/day) and Caribbean Coast (− 0.67 ± 0.12 mm/day), where LCC effects dampen CC effects by 24% and 72%, respectively. La Niña tends to intensify LCC and CC effects in the Andes but dampens them at the Coast, roughly by a factor of two compared to El Niño impacts in both regions. At the subregional level, LCC and CC can have impacts of similar magnitude on precipitation highlighting the need to precisely account for both drivers in hydroclimatic assessments. Contrary to almost all observations and similar simulations with climate models, WRF simulates a cooling bias after historical deforestation in Colombia, even with alternative WRF land surface models. We identify two main sources of biases in the default WRF parametrization to explain this inaccuracy: (1) surface shortwave radiation reflected after deforestation is overestimated; (2) associated evapotranspiration loss is underestimated. Improved model representation and validation of tropical vegetation properties are necessary to provide more robust and confident projections.

Gaps in adoption and implementation limit the current and potential effectiveness of zero-deforestation supply chain policies for soy

Tropical deforestation continues despite global efforts to curb forest loss. Corporate zero-deforestation supply chain commitments (ZDCs) have the potential to address this deforestation, especially if strong state-led forest governance is absent. Yet, because ZDC adoption is limited to particular locations and supply chains, these commitments may fall short at reducing regional deforestation and protecting biodiverse ecosystems. Here, we leverage timeseries of spatially explicit corporate commodity sourcing data and ZDCs to assess the current and potential effect of ZDCs within soybean supply chains on forest loss and biodiversity. We focus on the Brazilian Amazon, where the first ZDC (soy moratorium (SoyM)) was implemented, and the Cerrado, where companies have adopted but not implemented ZDCs. We found that in the Amazon, SoyM signatories that controlled the market caused a 57% reduction in direct deforestation for soy from 2006 to 2015. In the Cerrado, if companies had implemented their ZDCs with the same relative effectiveness as in the Amazon, deforestation for soy could have been reduced by 46%. Thus, ZDC implementation in the Cerrado via stringent monitoring and enforcement could contribute substantially to forest and habitat conservation. Yet, incomplete ZDC adoption leaves >50% of soy-suitable forests and the biodiversity that they harbor outside the reach of ZDCs. To protect these forests, it is vital to incentivize more companies—including smaller, less publicly exposed traders—to make and implement ZDCs, while also promoting forest governance through public policy.

Fueling Mexico: Energy and Environment, 1850–1950

Fueling Mexico: Energy and Environment, 1850–1950

Two Millennia of Complexity and Variability in a Perialpine Socioecological System (Savoie, France): The Contribution of Palynology and sedaDNA Analysis

Over the last two millennia, European Alpine ecosystems have experienced major changes in response to the important, yet fluctuating, impact of human activities. This study aims to reconstruct the environmental history of the last 1800 years on the western edge of the Alps by analyzing sediments from Lake Aiguebelette, a large lake located in the perialpine area. We have combined analyses of pollen and other palynomorphs, such as coprophilous fungal spores, together with sedimentary DNA (from plants and mammals) in order to reconstruct both vegetation and land-use histories. A sedimentological and geochemical analysis was also conducted in order to gain an understanding of changes in erosion dynamics in response to landscape modifications that were influenced by climate and human activities. This work highlights alternating phases of anthropization and agricultural abandonment allowing forest recovery. While pollen reflects the major phases of regional deforestation and afforestation related to the dynamic of farming activities, plant DNA provides precise information on the plants cultivated in fields, orchards and vegetable gardens over the past centuries. The combination of mammal DNA and coprophilous fungal spores completes this work by documenting the history of pastoral practices.

Ichthyofaunal diversity in the upper Jejuí River watershed in eastern Paraguay

ABSTRACT The upper Jejuí River is a major tributary of the Paraguay River in eastern Paraguay and is the principal drainage for the Mbaracayú Forest Biosphere Reserve. Despite the international significance of the biosphere reserve and detailed documentation of its terrestrial fauna and flora, the fish fauna in its streams remains relatively unknown, with 48 species previously recorded. We sampled 35 sites within the biosphere reserve over five years (2007–2011) to assess the richness of its ichthyofauna. These surveys yielded a new total of 105 known species for the biosphere reserve, including two newly-recorded orders, Gymnotiformes and Cyprinodontiformes, and 14 newly-recorded families. Fish community composition resembled that of previously-reported fish communities from the Paraguay River drainage, with characiforms and siluriforms comprising the majority of the species (57.1% and 31.4%, respectively). Post hoc analyses showed significantly greater ichthyofaunal diversity at sites within the Mbaracayú Forest Nature Reserve, a core protected forest area within the biosphere reserve, compared to areas outside the nature reserve, suggesting a negative impact from deforestation and land conversion on fish assemblages in these headwater streams. Broad regional deforestation places greater emphasis on important management decisions that will protect current biodiversity.

Financial Analysis of Potential Carbon Value over 14 Years of Forest Restoration by the Framework Species Method

The carbon storage value of forest restoration, by the framework species method (FSM) in northern Thailand, was assessed for trees (using a partial harvesting technique) and soil and compared with restoration costs. Forest carbon accumulation amounted to 143.08 tC/ha in trees and 8.56 tC/ha in soil over 14 years, with a combined value of USD 27,173.63 (net present value (NPV), discounted at 2.85%/year)) (at the current European carbon credit (EUA) price of 55.98 EUR/tCO2 = 242.21 USD/tC). Restoration costs increased from 2190.27 to 5680.72 USD/ha with declining pre-existing natural regeneration or 3.99–10.34 USD per ton of sequestered CO2. Profits over 14 years ranged in NPV from 22,215.45 to 25,157.04 USD/ha, breaking even from just over 4 years to just under 7, respectively. In contrast, profits from maize cultivation (a major regional deforestation driver) averaged 96.25 USD/ha/year, or just 1347.53 USD/ha over 14 years. Consequently, forest restoration could become a financially attractive alternative land use, provided an open, transparent, carbon market is created. Therefore, this study supports creation of a forest-carbon trading system in Thailand, to incentivize forest restoration and fire prevention, increase farmers’ incomes, reduce smoke-related public health problems, protect watersheds, and conserve biodiversity.

Conifer Forest Dynamics in the Iberian Pyrenees during the Middle Ages

This study compares the Medieval (ca. 400–1500 CE; Common Era) dynamics of forests from low-mountain (Montcortès; ca. 1000 m a.s.l.) and high-mountain (Sant Maurici; 1900 m a.s.l.) areas of the Iberian Pyrenees, both of which experienced similar climatic forcing but different anthropogenic pressures. The main aim is to identify forest changes over time and associate them with the corresponding climatic and anthropogenic drivers (or synergies among them) to test how different forests at different elevations respond to external forcings. This can be useful to evaluate the hypothesis of general Pyrenean deforestation during the Middle Ages leading to present-day landscapes and to improve the background for forest conservation. The study uses the palynological analysis of lake sediments, historical documents and paleoecological reconstructions based on pollen-independent proxies. The two sites studied showed different forest trajectories. The Montcortès area was subjected to intense human pressure during regional deforestation up to a maximum of ca. 1000 CE. Further forest recovery took place until the end of the Middle Ages due to a change in forest management, including the abandonment of slash-and-burn practices. Climatic shifts indirectly influenced forest trends by regulating human migrations and the resulting shifts in the type and intensity of forest exploitation. The highland Sant Maurici forests exhibited a remarkably long-standing constancy and an exceptional resilience to climatic shifts, which were unable to affect forest extension and composition, and to local human pressure, from which they rapidly recovered. The Montcortès and Sant Maurici records did not follow the rule of an irreversible forest clearing during the Middle Ages leading to present-day landscapes. The present Montcortès landscape was shaped after a Medieval forest recovery, new Modern-Age deforestation and further forest recovery during the last centuries. The Sant Maurici forests remained apparently untouched since the Bronze Age and were never cleared during the Middle Ages. The relevance of these findings for forest conservation is briefly addressed, and the need for the development of more high-resolution studies on Pyrenean forest dynamics is highlighted.

Regional deforestation drives the impact of forest cover and matrix quality on primate species richness

Land-use change transforms natural ecosystems, threatening species persistence worldwide. There is increasing evidence that forest loss negatively affects forest-dependent species and matrix quality can favor species maintenance, whereas forest fragmentation has mainly null or positive effects on species. However, the effects of these landscape attributes may depend on the level of regional deforestation. Here, we assess the effects of forest cover, matrix quality, and forest fragmentation (forest patch density) on primate species richness in 92 landscapes in Brazil. We grouped landscapes by their regional deforestation level into low, intermediate, high, and severe deforestation. The effects of landscape attributes varied depending on the level of regional deforestation. Forest loss decreased the proportion of primate species in the four regional deforestation levels, but this association was more important in the low, intermediate and high regional deforestation levels. Matrix quality was positively related to the proportion of primate species in three regional deforestation levels and this association was more important in the high regional deforestation level. Yet, matrix quality decreased the proportion of primate species in the severe regional deforestation level. Forest fragmentation had no clear effects across all deforestation levels. Therefore, different conservation strategies should be prioritized under distinct scenarios. Preventing forest loss is needed in all regions. Increasing matrix quality has positive effects on species richness, especially in highly deforested regions (30–15% remaining forest cover). Finally, as fragmentation had no clear effects on the proportion of primate species, landscape composition should be prioritized in conservation planning over landscape configuration.

Climate and human induced 2000-year vegetation diversity change in Yunnan, southwestern China

Understanding long-term vegetation diversity patterns and their potential responses to climate and/or human driven processes are important for ecosystem modeling and conservation. Late-Holocene fossil pollen assemblage and associated vegetation diversity estimates provide an opportunity to explore the interactions among vegetation, climate, and human activities. A continuous 2000-year palynological record was obtained from the Beihai Wetland, southwestern China, to represent regional vegetation history, particularly the vegetation diversity changes. The results indicate that regional vegetation was dominated by deciduous broadleaved forest components (e.g. Alnus, deciduous Quercus), which showed a gradual decrease accompanied by expansion of herbaceous taxa (mainly Poaceae) after AD 800. Such progressive decline of forest was attributed to regional deforestation driven by intensified human activities, which was further confirmed by the increasing non-pollen polymorph abundance, particularly an abrupt rise after AD 1350. Vegetation diversity based on the Hill numbers ( N0, N1, and N2) showed a dramatic decline between ca. AD 200–400, which was triggered by regional fire events as shown by increased charcoal abundance from a nearby lake. The vegetation diversity reduced gradually after AD 800, especially the vegetation richness reflected by N0, revealing the transitional process from climate-driven to human-dominated vegetation changes. Minor increases of vegetation diversity occurred during Chinese dynastical transitions, probably due to reduced human activities following war-induced population crises. On the multidecadal scale, variations in vegetation diversity correlated significantly with climate fluctuations (revealed by synthesized temperature of China and stable oxygen isotope record from Dongge Cave) before AD 800, indicating a climate dominant condition. Then, the correlation between vegetation diversity and climate declined after AD 800, representing a progressive transition to human-dominant condition. In addition, the compositional turnover based on DCCA of the fossil pollen assemblage revealed a stepwise decrease, indicating reduced vegetation turnovers under anthropogenic influences.

Dynamics of deforestation worldwide: A structural decomposition analysis of agricultural land use in South America

Deforestation, mainly caused by the conversion of forest land to agriculture, threatens the achievement of multiple goals across the 2030 Agenda. This environmental issue is particularly marked in the area formed by Argentina, Brazil, and Paraguay (ABP region), where a net forest loss of more than 5,5 million hectares per year and a simultaneous net gain in agricultural land of almost 3 million hectares were registered during 2000–2015. To identify the main contributors to the growth in agricultural land use driving regional deforestation, a Structural Decomposition Analysis (SDA) is applied on multiregional input-output tables. Results suggest that changes detected within ABP were mainly influenced by shifts in domestic demand and exacerbated by the influence of Brazil within the Mercosur trade agreement. Outside ABP, results show that consumption per capita and population expansion in developed and developing economies (the EU28, the US, and China) are major drivers of regional deforestation. Although globalization led to a surge in the ABP’s land displaced to other countries, our results indicate that outsourced agricultural activities did not affect the growth in ABP’s agricultural land use. There is thus a need of designing mitigation measures with a global sense that also addresses co-responsibility mechanisms among countries in the region.

Effects of household-level attributes and agricultural land-use on deforestation patterns along a forest transition gradient in the Miombo landscapes, Zambia

Dry forests in tropical and subtropical areas continue to experience high deforestation rates that affect households' dependence on forest resources. Little remains understood about the relationship between household factors and deforestation patterns in Zambia. We integrate remotely sensed data with surveys of 1123 households collected in the Miombo areas between 2017 and 2019 to better understand the effects of household attributes on regional deforestation patterns along a forest transition gradient.We found, in early-to-mid-transition, deforestation patterns systematically decreased further from settlements (homesteads), but this was reversed in regions with advanced forest transition. The socio-demographic attributes, land and non-land-based attributes, and location factors differently affected deforestation across provinces. Although agricultural land-use was significantly associated with deforestation, no distinct patterns emerged across distance categories or along the forest transition. Furthermore, increases in non-farm income reduced the likelihood of high deforestation, but the impact was not always significant across provinces.Our results indicate that economic effects of distance in Miombo areas complement the forest transition, but are not exclusively related to crop productivity. We assume that different aspects of livelihoods can explain the deforestation patterns in the Miombo areas. Thus, forest management should be regional-specific, such as improving access to financial incentives in North-Western, and reforestation and agroforestry in Copperbelt and the Eastern Province.

Post-conflict transition and REDD+ in Colombia: Challenges to reducing deforestation in the Amazon

REDD+ is a mechanism to address climate change by reducing deforestation and forest degradation. In this article, the implementation of the REDD Early Movers- REM/Visión Amazonia program in Guaviare, Colombia, is analyzed, focusing on the implementation challenges and scope of the program when addressing deforestation drivers in a post-conflict context. By taking a historical perspective on regional deforestation challenges in Guaviare, we link these challenges to the recent deforestation trends in the region. This article demonstrates the particular challenges to implementing REDD+ in the Colombian post-conflict context related to the power vacuum left by the FARC retreat, land grabbing for speculation and cattle ranching, power asymmetries and corrupted regional elites. The article concludes that the current scope of REM does not sufficiently address the main drivers of deforestation, and that REM's focus on campesinos and indigenous communities will not significantly reduce the substantial deforestation rates in the present post-conflict context.

Evidence for fungal proliferation following the Cretaceous/Paleogene mass-extinction event, based on chemostratigraphy in the Raton and Powder River basins, western North America

The presence of the amino acid α-aminoisobutyric acid (Aib) within Cretaceous/Paleogene (K/Pg) boundary clay in the Raton and Powder River basins in Colorado and Wyoming, respectively, has been described as compelling evidence that extraterrestrial Aib survived the high-energy Chicxulub impact. Based on contemporary experiments and simulations, however, it is highly unlikely that extraterrestrial Aib survived the impact, which had peak impact pressures and temperatures in excess of 600 GPa and 10,000 K, respectively. In other words, the amino acid signature of the carbonaceous chondritic asteroid that impacted Chicxulub was undoubtedly destroyed upon impact during formation of the vapor plume or so-called “fireball.” The only organisms known to produce Aib are the suite (more than 30 genera) of cosmopolitan saprotrophic filamentous fungi that include Trichoderma Pers., which has recently been hypothesized to have thrived during the K/Pg mass-extinction event. Therefore it is proposed that the Aib horizon in the K/Pg boundary clay in the Raton and Powder River basins correlates with the K/Pg boundary fungal spike, which thus far has only been observed in New Zealand (Southern Hemisphere). This proposition is based upon superimposing the Aib horizon on the well-known iridium and fern-spore spikes, as its stratigraphic position precisely matches that predicted by the fungal spike. If correct, this hypothesis alters the conventional perspective on the tempo and mode of terrestrial ecosystem recovery in western North America, as the heavily sampled K/Pg boundary section in the Raton Basin was instrumental in shaping the traditional narrative of the rapid recolonization of a denuded landscape by ferns via wind-blown spores in the immediate wake of regional deforestation caused by the K/Pg impact event. Perhaps more importantly, it could present an alternative to traditional palynological approaches for locating the fungal spike in other terrestrial K/Pg boundary sections and could provide additional support for the generalization that global mass-extinction events are frequently accompanied by fungal spikes.

A regional evaluation of the effectiveness of Mexico’s payments for hydrological services

Recent criticisms of, and financial limits on, payment for hydrologic services (PHS) programs suggest that rigorous, spatially explicit evaluations are urgently needed to improve their effectiveness in conserving forest cover and to justify payments. To evaluate the effectiveness of Mexico’s PHS programs in the Pixquiac and Gavilanes subwatersheds in central Veracruz state, we used a grid-based approach to (1) compare the suitability of national versus regional deforestation risk models in selecting the parcels that should receive payment and (2) evaluate three metrics of program effectiveness in parcels receiving PHS: forest cover loss, additionality associated with deforestation risk, and leakage. Our results suggest that the national deforestation risk model was less effective at predicting actual deforestation patterns and tended to underestimate deforestation risk vs. models run regionally. Regional analysis showed parcels receiving PHS exhibited significantly lower deforestation in plots receiving PHS (0.76% loss) vs. control areas (6.29%) between 2003 and 2013. Furthermore, we found relatively poor additionality with only 38.5% of PHS occurring in zones with high or very high deforestation probability. Finally, we did not detect significant evidence of proximal leakage in our study subwatersheds. Our findings suggest that the PHS programs in central Veracruz have helped to reduce, but not stop forest loss completely. Using increased targeting of areas with higher deforestation risk in selecting PHS areas and updated regional deforestation risk models should be helpful in evaluating and increasing the effectiveness of these programs.

O turismo como um instrumento de proteção florestal na Amazônia: uma análise multivariada

Propósito do tema: A crescente demanda internacional por bens primários tem gerado oportunidades excepcionais para a mineração e para o agronegócio na Amazônia. Isto está promovendo, em muitos casos, a perda progressiva da cobertura do solo. Muitas são as estratégias propostas para a contenção do desmatamento regional, ente elas, o turismo, apontado como uma atividade econômica alternativa e mais sustentável para a região. Objetivo: A finalidade deste estudo foi estimar a importância relativa do turismo para o ritmo do desmatamento no bioma Amazônia no período 2015/2016. Metodologia e abordagem: Foram utilizadas séries de corte para as 91 microrregiões geográficas do bioma, nas quais foi aplicada a técnica de regressão linear múltipla associada à decomposição das covariâncias pela Medida de Pratt. Resultados: Os resultados sugerem que o desmatamento é uma função da pecuária bovina, da agricultura, da extração de madeira, dos assentamentos rurais, das áreas protegidas e, entre outros, do turismo. Identificou-se uma correlação inversa entre o turismo e as taxas anuais de desmatamento do bioma. Originalidade: Os resultados deste estudo permitem propor o desenvolvimento responsável do turismo como uma estratégia para a proteção da cobertura florestal da Amazônia.

Biophysical effects on temperature and precipitation due to land cover change

Anthropogenic land cover changes (LCC) affect regional and global climate through biophysical variations of the surface energy budget mediated by albedo, evapotranspiration, and roughness. This change in surface energy budget may exacerbate or counteract biogeochemical greenhouse gas effects of LCC, with a large body of emerging assessments being produced, sometimes apparently contradictory. We reviewed the existing scientific literature with the objective to provide an overview of the state-of-the-knowledge of the biophysical LCC climate effects, in support of the assessment of mitigation/adaptation land policies. Out of the published studies that were analyzed, 28 papers fulfilled the eligibility criteria, providing surface air temperature and/or precipitation change with respect to LCC regionally and/or globally. We provide a synthesis of the signal, magnitude and uncertainty of temperature and precipitation changes in response to LCC biophysical effects by climate region (boreal/temperate/tropical) and by key land cover transitions. Model results indicate that a modification of biophysical processes at the land surface has a strong regional climate effect, and non-negligible global impact on temperature. Simulations experiments of large-scale (i.e. complete) regional deforestation lead to a mean reduction in precipitation in all regions, while air surface temperature increases in the tropics and decreases in boreal regions. The net global climate effects of regional deforestation are less certain. There is an overall consensus in the model experiments that the average global biophysical climate response to complete global deforestation is atmospheric cooling and drying. Observed estimates of temperature change following deforestation indicate a smaller effect than model-based regional estimates in boreal regions, comparable results in the tropics, and contrasting results in temperate regions. Regional/local biophysical effects following LCC are important for local climate, water cycle, ecosystems, their productivity and biodiversity, and thus important to consider in the formulation of adaptation policy. However before considering the inclusion of biophysical climate effects of LCC under the UNFCCC, science has to provide robust tools and methods for estimation of both country and global level effects.