Belowground changes to community structure alter methane-cycling dynamics in Amazonia

ABSTRACTAmazonian rainforest is undergoing increasing rates of deforestation, driven primarily by cattle pasture expansion. Forest-to-pasture conversion has been associated with changes to ecosystem processes, including substantial increases in soil methane (CH4) emission. The drivers of this change in CH4 flux are not well understood. To address this knowledge gap, we measured soil CH4 flux, environmental conditions, and belowground microbial community attributes across a land use change gradient (old growth primary forest, cattle pasture, and secondary forest regrowth) in two Amazon Basin regions. Primary forest soils exhibited CH4 uptake at modest rates, while pasture soils exhibited CH4 emission at high but variable rates. Secondary forest soils exhibited low rates of CH4 uptake, suggesting that forest regrowth following pasture abandonment could reverse the CH4 sink-to-source trend. While few environmental variables were significantly associated with CH4 flux, we identified numerous microbial community attributes in the surface soil that explained substantial variation in CH4 flux with land use change. Among the strongest predictors were the relative abundance and diversity of methanogens, which both increased in pasture relative to forests. We further identified individual taxa that were associated with CH4 fluxes and which collectively explained ~50% of flux variance. These taxa included methanogens and methanotrophs, as well as taxa that may indirectly influence CH4 flux through acetate production, iron reduction, and nitrogen transformations. Each land type had a unique subset of taxa associated with CH4 fluxes, suggesting that land use change alters CH4 cycling through shifts in microbial community composition. Taken together, our results suggest that changes in CH4 flux from agricultural conversion could be driven by microbial responses to land use change in the surface soil, with both direct and indirect effects on CH4 cycling. This demonstrates the central role of microorganisms in mediating ecosystem responses to land use change in the Amazon Basin.

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Pola Perubahan Penggunaan Lahan Sub Sub Daerah Aliran Sungai (DAS) Cikujang

Rona Teknik Pertanian ◽

10.17969/rtp.v9i2.5651 ◽

2016 ◽

Vol 9 (2) ◽

pp. 147-156

Author(s):

Devianti Devianti

Keyword(s):

Land Use ◽

Land Use Change ◽

Protected Area ◽

Catchment Area ◽

Rice Field ◽

Secondary Forest ◽

Forest Area ◽

Primary Forest ◽

Change Pattern ◽

Changing Rate

Abstrak. Sub Sub DAS Cikujang merupakan salah satu bagian dari Sub DAS Cimanuk hulu yang dapat menyumbang sedimen ke waduk Jatigede yang berasal dari erosi sebagai akibat perubahan penggunaan lahan yang tidak sesuai dengan kondisi fisik lahan. Hasil kajian memperlihatkan pola perubahan penggunaan lahan di Sub Sub DAS Cikujang periode 1994-2009, terjadi perubahan penggunaan lahan dari kawasan lindung menjadi kawasan budidaya seluas 742,20 ha. Kawasan lindung pada tahun 1994 seluas 3.213,03 ha menurun menjadi 2.470,83 ha pada tahun 2009 dan kawasan budidaya pada tahun 1994 seluas 9.532,41 ha meningkat menjadi 10.274,61 ha pada tahun 2009 dengan laju perubahan 185,55 ha/tahun. Laju penurunan luasan hutan primer mencapai 54,45 ha/tahun, dan pada tahun 2009 tidak terdapat lagi lahan dengan fungsi sebagai hutan primer. Laju penurunan luasan hutan sekunder mencapai 135,90 ha/tahun dari 2.995,25 ha pada tahun 1994 menjadi 2.451,65 ha pada tahun 2009. Pola perubahan penggunaan lahan di Sub Sub DAS Cikujang sebagian besar dipengaruhi dengan pola perubahan hutan primer dan hutan sekunder pada kawasan lindung. Sedangkan pola perubahan penggunaan lahan pada kawasan budidaya dipengaruhi pola perubahan lahan kebun campuran, tegalan/ladang, perkebunan, dan sawah Land-Use Change Pattern in Cikujang Catchment Area Abstract. Cikujang catchment area is one part of the subzone Cimanuk that can contribute sediment upstream reservoirs to Jatigede derived from erosion as a result of changes in land use that is not in accordance with the physical condition of the land. Based on analysis result of land-use change pattern in Cikujang catchment area in 1994 – 2009 period, land-use had changed 742,20ha from protected areas to cultivated areas, where protected area had decreased from 3.213,03ha in 1994 to 2.470,83ha in 2009 and cultivated area had increased from 10.274,61 ha in 1994 to10.274,61 ha in 2009 with changing rate ha/year. The rate of decreasing primary forest area was 54.45ha/year, as a result there was no land function as primary forest in 2009. The rate of decreasing secondary forest area was 135,90ha/year ranging from 2.995,25ha in 1994 to 2.451,65ha in 2009. Land-use change pattern in Cikujang catchment area dominantly was influenced by changing pattern of protected forest and secondary forest in protected area, but in cultivated area land-use change pattern was influenced by changing pattern of farm, grassland, and rice field.

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Land use change in Amazonian Dark Earth and Acrisol: Responses of organic carbon, organic matter composition and microbial carbon utilisation

10.5194/egusphere-egu2020-19752 ◽

2020 ◽

Author(s):

Klaus Jarosch ◽

Luis Carlos Colocho Hurtarte ◽

Konstantin Gavazov ◽

Aleksander Westphal Muniz ◽

Christoph Müller ◽

...

Keyword(s):

Land Use ◽

Organic Matter ◽

Community Structure ◽

Microbial Community ◽

Organic Carbon ◽

Land Use Change ◽

Microbial Community Structure ◽

Secondary Forest ◽

Soil Types ◽

Amazonian Dark Earth

The conversion of tropical forest for cassava cultivation is widely known to decrease the soil organic matter (OM) and nutrient contents of highly weathered soils in the tropics. Amazonian Dark Earth (ADE) might be affected less due to their historical anthropogenic amelioration with e.g. charcoal, ceramics and bones, leading to higher soil OM and nutrient concentrations. In this study, we analysed the effect of land use change on the OM dynamics and its composition under tropical conditions, using ADE and an adjacent Acrisol (ACR) as model systems. Soil samples were obtained south of Manaus (Brazil), from a secondary forest and an adjacently located 40-year-old cassava plantation. The land use change induced a severe decrease of organic carbon (OC) concentrations in ADE (from 35 to 15&#160;g&#160;OC&#160;kg&#8209;1) while OC in the adjacent ACR was less affected (18 to 16&#160;g&#160;OC&#160;kg&#8209;1). Soils were analysed by 13C NMR spectroscopy to obtain information on how the conversion of secondary forest to cassava affected the chemical composition of OM. Our results show that land use change induces differences in the OM composition: The OM in ADE changes to a more decomposed state (increase of alkyl:O/N-alkyl ratio) whereas the OM in ACR changes to a less decomposed state (decrease of alkyl:O/N-alkyl ratio). According to a molecular mixing model, land use change influenced mostly the proportion of lipids, which might be related with a change of the plant input. The incubation of the soils with 13C glucose enabled resolving how soil microorganisms were affected by land use change. In both soil types ADE and ACR, land use change caused a reduction of the total 13C glucose respiration by approximately one third in a 7-days incubation, implying lower microbial activity. Microorganisms in both soil types appear to be more readily active in soils under forest, since we observed a distinct lag time between 13C glucose addition and respiration under cassava planation. This indicated differences in microbial community structure, which we will assess further by determining the 13C label uptake by the microbial biomass and the microbial community structure using 13C PLFA analysis. Preliminary results from synchrotron-based STXM demonstrate a distinct arrangement of OM at fine-sized charcoal-particle interfaces. Samples of soils receiving 13C label will be further analysed by NanoSIMS with the hypothesis that charcoal interfaces foster nutrient dynamics at the microscale. Despite the high loss of OC in the ameliorated ADE through land use change, the remaining OM might improve the nutrient availability thanks to charcoal interactions compared to the ACR. Our results contribute to a better understanding of the sensitivity of OM upon land use change and how the microbial community is responding to land use change in highly weathered tropical soils.

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KAJIAN PENANGGULANGAN KERUSAKAN LAHAN AKIBAT PERUBAHAN PENGGUNAAN LAHAN DENGAN PENDEKATAN MODEL HIDROLOGI PADA DAS PAMI

Agrotek ◽

10.30862/agt.v5i6.598 ◽

2018 ◽

Vol 5 (6) ◽

Author(s):

Kati Syamsudin Kadang Tola ◽

Siti Hadjar Kubangun

Keyword(s):

Land Use ◽

Land Use Change ◽

Secondary Forest ◽

Secondary Data ◽

Soil Sampling ◽

Peak Discharge ◽

Primary Data ◽

Primary Forest ◽

Peak Flows ◽

Administrative Area

Changes in land use in watershed will affect peak discharge and degradation land. It is becoming an indicator of better or worse use of land in watershed area. This study aims to analysis land use change, to predict peak flows based on changes in land use and land use change scenarios in the Pami watershed. This study uses a number of primary data and secondary data. Primary data were obtained from observations of the condition of the land and soil sampling, which is then analyzed in the laboratory. Secondary data were obtained from literature and related agencies such as geographical map and thematic maps including land map, administrative area maps, land use maps in 1996-2015 and rainfall in 1996-2015. Data analysis included analysis of changes in land use, identification of watershed characteristics and hydrology analysis. Research results showed that changes in land use in 1996-2015 was dominated by primary forest but experiencing a decline around 39,94%. While land use included secondary forest and settlement area were increased by 73,10% and 70,61% respectively. Predicted peak flows based on changes in land use obtained the average of peak discharge in 1996 was about 118.7 m3/sec, while the average of peak discharge in 2015 amounted to 157.4 m3/sec where there is an increase of 33.5 %. Scenarios of land use change conducted in the mixed farming in Pami watershed obtained peak discharge of 157.4 m3/sec

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Contributions of secondary forest and nitrogen dynamics to terrestrial carbon uptake

Biogeosciences Discussions ◽

10.5194/bgd-7-2739-2010 ◽

2010 ◽

Vol 7 (2) ◽

pp. 2739-2765 ◽

Cited By ~ 1

Author(s):

X. Yang ◽

T. K. Richardson ◽

A. K. Jain

Keyword(s):

Land Use ◽

Land Use Change ◽

Secondary Forest ◽

Nitrogen Dynamics ◽

Carbon Uptake ◽

Secondary Forests ◽

Terrestrial Carbon ◽

Tropical Regions ◽

Forest Regrowth ◽

Limiting Nutrient

Abstract. We use a terrestrial carbon-nitrogen cycle component of the Integrated Science Assessment Model (ISAM) to investigate the impacts of nitrogen dynamics on regrowing secondary forests over the 20th century. We further examine what the impacts of nitrogen deposition and land use change history are on terrestrial carbon uptake since preindustrial time. Our results suggest that global total net land use emissions for the 1990s associated with changes in cropland, pastureland, and wood harvest are 1.22 GtC/yr. Without considering the secondary forest regrowth, the estimated net global total land use emissions are 1.58 GtC/yr or about 0.36 GtC/yr higher than if secondary forest regrowth is considered. Results also show that without considering the nitrogen dynamics and deposition, the estimated global total secondary forest sink for the 1990s is 0.90 GtC/yr or about 0.54 GtC/yr higher than estimates that include the impacts of nitrogen dynamics and deposition. Nitrogen deposition alone is responsible for about 0.13 GtC/yr of the total secondary forest sink. While nitrogen is not a limiting nutrient in the intact primary forests in tropical regions, our study suggests that nitrogen becomes a limiting nutrient for regrowing secondary forests of the tropical regions, in particular Latin America and Tropical Africa. This is because land use change activities, especially wood harvest, removes large amounts of nitrogen from the system when slash is burnt or wood is removed for harvest. However, our model results show that carbon uptake is enhanced in the tropical secondary forests of the Indian region. We argue that this may be due to enhanced nitrogen mineralization and increased nitrogen availability following land use change in the Indian tropical forest ecosystems. Results also demonstrate that there is a significant amount of carbon accumulating in the Northern Hemisphere where most land use changes and forest regrowth has occurred in recent decades. This study indicates the significance of secondary forests to terrestrial carbon sinks, the importance of nitrogen dynamics to the magnitude of secondary forests carbon uptake, and therefore the need to include both primary and secondary forests and nitrogen dynamics in terrestrial ecosystem models.

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Contributions of secondary forest and nitrogen dynamics to terrestrial carbon uptake

Biogeosciences ◽

10.5194/bg-7-3041-2010 ◽

2010 ◽

Vol 7 (10) ◽

pp. 3041-3050 ◽

Cited By ~ 31

Author(s):

X. Yang ◽

T. K. Richardson ◽

A. K. Jain

Keyword(s):

Land Use ◽

Land Use Change ◽

Secondary Forest ◽

Nitrogen Dynamics ◽

Carbon Uptake ◽

Secondary Forests ◽

Terrestrial Carbon ◽

Tropical Regions ◽

Forest Regrowth ◽

Limiting Nutrient

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Response of Free-Living Nitrogen-Fixing Microorganisms to Land Use Change in the Amazon Rainforest

Applied and Environmental Microbiology ◽

10.1128/aem.02362-13 ◽

2013 ◽

Vol 80 (1) ◽

pp. 281-288 ◽

Cited By ~ 55

Author(s):

Babur S. Mirza ◽

Chotima Potisap ◽

Klaus Nüsslein ◽

Brendan J. M. Bohannan ◽

Jorge L. M. Rodrigues

Keyword(s):

Land Use ◽

Land Use Change ◽

Plant Communities ◽

Secondary Forest ◽

Marker Gene ◽

Amazon Rainforest ◽

Primary Forest ◽

Nitrogen Fixing ◽

Free Living ◽

Total N

ABSTRACTThe Amazon rainforest, the largest equatorial forest in the world, is being cleared for pasture and agricultural use at alarming rates. Tropical deforestation is known to cause alterations in microbial communities at taxonomic and phylogenetic levels, but it is unclear whether microbial functional groups are altered. We asked whether free-living nitrogen-fixing microorganisms (diazotrophs) respond to deforestation in the Amazon rainforest, using analysis of the marker genenifH. Clone libraries were generated from soil samples collected from a primary forest, a 5-year-old pasture originally converted from primary forest, and a secondary forest established after pasture abandonment. Although diazotroph richness did not significantly change among the three plots, diazotroph community composition was altered with forest-to-pasture conversion, and phylogenetic similarity was higher among pasture communities than among those in forests. There was also 10-fold increase innifHgene abundance following conversion from primary forest to pasture. Three environmental factors were associated with the observed changes: soil acidity, total N concentration, and C/N ratio. Our results suggest a partial restoration to initial levels of abundance and community structure of diazotrophs following pasture abandonment, with primary and secondary forests sharing similar communities. We postulate that the response of diazotrophs to land use change is a direct consequence of changes in plant communities, particularly the higher N demand of pasture plant communities for supporting aboveground plant growth.

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Consequences of land use change on soil organic matter composition and C-P relationships in Amazonian Dark Earth and Acrisol

10.5194/egusphere-egu21-15580 ◽

2021 ◽

Author(s):

Klaus A Jarosch ◽

Luis Carlos Colocho Hurtarte ◽

Konstantin Gavazov ◽

Aleksander Westphal Muniz ◽

Christoph Müller ◽

...

Keyword(s):

Land Use ◽

Organic Matter ◽

Community Structure ◽

Microbial Community ◽

Soil Organic Matter ◽

Land Use Change ◽

Microbial Community Structure ◽

Secondary Forest ◽

Soil Types ◽

Amazonian Dark Earth

The conversion of tropical forest for cassava cultivation is widely known to decrease the soil organic matter (OM) and nutrient contents of highly weathered soils in the tropics. Amazonian Dark Earth (ADE) might be more resistant to this process due to their historical anthropogenic amelioration with e.g. charcoal, ceramics and bones, leading to higher soil OM and nutrient concentrations. In this study, we analyzed the effect of land use change on the OM dynamics under tropical conditions and how this is related with P distribution at the microscale, using ADE and an adjacent Acrisol (ACR) as model systems. Soil samples were obtained south of Manaus (Brazil), from a secondary forest and an adjacently located 40-year-old cassava plantation. The land use change induced a severe decrease of organic carbon (OC) concentrations in ADE (from 35 to 15&#160;g&#160;OC&#160;kg&#8209;1) while OC in the adjacent ACR was less affected (18 to 16&#160;g&#160;OC&#160;kg&#8209;1). The analysis by 13C NMR spectroscopy showed that the conversion of secondary forest to cassava changed the chemical composition of OM to a more decomposed state (increase of alkyl:O/N-alkyl ratio) in the ADE whereas the OM in ACR changed to a less decomposed state (decrease of alkyl:O/N-alkyl ratio). According to neutral sugar and lipid extraction analyses, land use change led to a larger impact on the microbial-derived and plant-derived compounds in the ADE compared to the ACR. In order to analyze the interactions of OC and P at the microscale, we conducted an incubation experiment with 13C glucose for the analysis with Scanning X-ray Microscopy (SXM) and Nano scale Secondary Ion Mass Spectrometry (NanoSIMS). In both soil types ADE and ACR, land use change caused a reduction of the total 13C glucose respiration by approximately one third in a 7-days incubation, implying lower microbial activity. Microorganisms in both soil types appear to be more readily active in soils under forest, since we observed a distinct lag time between 13C glucose addition and respiration under cassava planation. This indicated differences in microbial community structure, which we will be assessed further by determining the 13C label uptake by the microbial biomass and the microbial community structure using 13C PLFA analysis. Preliminary results from synchrotron-based STXM demonstrate a distinct arrangement of OM at fine-sized charcoal-particle interfaces. From ongoing NanoSIMS analyses, we expect further insights on the co-localization of P and 13C-labelled spots at the microscale. Despite the high loss of OC in the ameliorated ADE through land use change, the remaining OM might foster nutrient dynamics at the microscale thanks to charcoal interactions compared to the ACR. Our results contribute to a better understanding of the C and P interactions and how these respond to land use change in highly weathered tropical soils.

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Changes in Land Cover Analysis in The Gulf Coast Kendari Using High Resolution Satellite Image (Period: 2003-2009)

Forum Geografi ◽

10.23917/forgeo.v27i2.2375 ◽

2013 ◽

Vol 27 (2) ◽

pp. 179 ◽

Cited By ~ 1

Author(s):

Laode Muh. Golok Jaya

Keyword(s):

Land Use ◽

Land Use Change ◽

Land Cover ◽

Public Space ◽

Land Cover Change ◽

Satellite Imagery ◽

Gulf Coast ◽

Secondary Forest ◽

Satellite Image ◽

Primary Forest

This research was aimed to indentify land cover change in coastal area of Kendari Bay in period 2003 to 2009. The satellite imagery data (Ikonos and Quick Bird) collected in 2003 and 2009 were used in this research to obtain the land cover change. The method used in this research was comparing the classification of satellite imagery. Field survey was conducted using handheld GPS for ground truth. The result of this research showed us the land use change in period 2003-2009. Mangrove vegetation decreased 56.57 Ha and the fishpond also decreased 205.5 Ha. The primary forest decreased into 3.28 Ha in year 2009. The secondary forest also decreases 124.84 Ha. In the same time the urban area increased from 382.37 Ha in year 2003 to 674.37 Ha in 2009. The land use change also occured for the public space which increased from 6.49 Ha in 2003 to 18.46 Ha in 2009 or increased 11,97 Ha.

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MANAJEMEN DATA SPASIAL: PENGGUNAAN TANAH WILAYAH PEDESAAN DI SUMATERA BARAT

Jurnal Spasial ◽

10.22202/js.v5i2.3090 ◽

2019 ◽

Vol 5 (2) ◽

pp. 48-53

Author(s):

Afrital Rezki, S.Pd., M.Si ◽

Erna Juita ◽

Dasrizal Dasrizal ◽

Arie Zella Putra Ulni

Keyword(s):

Land Use ◽

Paddy Field ◽

Secondary Forest ◽

Water Bodies ◽

Primary Forest ◽

Land Uses ◽

Forest Land ◽

Land Use Patterns ◽

Crop Fields ◽

Mixed Plantations

Perkembangan penggunaan tanah bergerak horisontal secara spasial ke arah wilayah yang mudah diusahakan. Penggunaan tanah juga bergerak secara vertikal dalam rangka menaikkan mutunya. Penelitian ini bertujuan untuk menganalisis pola penggunaan lahan, bagaimana manajemen penggunaan lahan di satu wilayah berdasarkan batas Nagari. Metode yang digunakan adalah analsisis spasial dengan interpretasi citra penginderaan jauh, survey lapangan, dan analisis deskriptif. Pertumbuhan pemukiman Nagari Sungai Sariak Kecamatan VII Koto Kabupaten Padang Pariaman mengakibatkan pemanfaatan ruang menjadi tumpang tindih. Diperlukan cara-cara pengelolaan dan managemen penggunaan tanah dalam rangka pembangunan berkelanjutan yang menaikkan taraf hidup masyarakat dan tidak menimbulkan kerugian lingkungan.Terdapat 9 jenis penggunaan lahan yang ada di Nagari Sungai Sariak. Penggunaan lahan tersebut adalah Primary Forest, Secondary Forest, Paddy Field, Settlement, Mixed Plantations, Crop Fields, Water Bodies, Bushes, dan Plantations. Penggunaan lahan yang paling luas di Nagari Sungai Sariak adalah jenis penggunaan lahan Primary Forest, sebesar 48% dari total luas wilayah Nagari Sungai Sariak. Pada tahun 2011 sampai tahun 2016, penggunaan lahan paling luas terjadi pada penggunaan lahan jenis Primary Forest yang kemudian menjadi Mixed Plantations. Land use Changes moved horizontally spatially towards areas that are easily cultivated. The land use also moves vertically in order to increase its quality. This study aims to analyze land use patterns, how land use management in one area is based on Nagari boundaries. The method used is spatial analysis with interpretation of remote sensing images, field surveys, and descriptive analysis. The growth of Nagari Sungai Sariak in Kecamatan VII Koto, Kabupaten Padang Pariaman resulted in overlapping use of space. Management methods are needed and management of land use in the framework of sustainable development that raises the standard of living of the community and does not cause environmental losses. There are 9 types of land use in the Nagari Sungai Sariak. The land uses are Primary Forest, Secondary Forest, Paddy Field, Settlement, Mixed Plantations, Crop Fields, Water Bodies, Bushes, and Plantations. The most extensive land use in Nagari Sungai Sariak is the type of Primary Forest land use, amounting to 48% of the total area of the Nagari Sungai Sariak. From 2011 to 2016, the most extensive land use occurred in Primary Forest land uses which later became Mixed Plantations.

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Deforestation in Amazonia impacts riverine carbon dynamics

Earth System Dynamics ◽

10.5194/esd-7-953-2016 ◽

2016 ◽

Vol 7 (4) ◽

pp. 953-968 ◽

Cited By ~ 2

Author(s):

Fanny Langerwisch ◽

Ariane Walz ◽

Anja Rammig ◽

Britta Tietjen ◽

Kirsten Thonicke ◽

...

Keyword(s):

Land Use ◽

Organic Carbon ◽

Land Use Change ◽

Atlantic Ocean ◽

Amazon Basin ◽

Inorganic Carbon ◽

Carbon Dynamics ◽

Model System ◽

Atmospheric Co2 ◽

Terrestrial Productivity

Abstract. Fluxes of organic and inorganic carbon within the Amazon basin are considerably controlled by annual flooding, which triggers the export of terrigenous organic material to the river and ultimately to the Atlantic Ocean. The amount of carbon imported to the river and the further conversion, transport and export of it depend on temperature, atmospheric CO2, terrestrial productivity and carbon storage, as well as discharge. Both terrestrial productivity and discharge are influenced by climate and land use change. The coupled LPJmL and RivCM model system (Langerwisch et al., 2016) has been applied to assess the combined impacts of climate and land use change on the Amazon riverine carbon dynamics. Vegetation dynamics (in LPJmL) as well as export and conversion of terrigenous carbon to and within the river (RivCM) are included. The model system has been applied for the years 1901 to 2099 under two deforestation scenarios and with climate forcing of three SRES emission scenarios, each for five climate models. We find that high deforestation (business-as-usual scenario) will strongly decrease (locally by up to 90 %) riverine particulate and dissolved organic carbon amount until the end of the current century. At the same time, increase in discharge leaves net carbon transport during the first decades of the century roughly unchanged only if a sufficient area is still forested. After 2050 the amount of transported carbon will decrease drastically. In contrast to that, increased temperature and atmospheric CO2 concentration determine the amount of riverine inorganic carbon stored in the Amazon basin. Higher atmospheric CO2 concentrations increase riverine inorganic carbon amount by up to 20 % (SRES A2). The changes in riverine carbon fluxes have direct effects on carbon export, either to the atmosphere via outgassing or to the Atlantic Ocean via discharge. The outgassed carbon will increase slightly in the Amazon basin, but can be regionally reduced by up to 60 % due to deforestation. The discharge of organic carbon to the ocean will be reduced by about 40 % under the most severe deforestation and climate change scenario. These changes would have local and regional consequences on the carbon balance and habitat characteristics in the Amazon basin itself as well as in the adjacent Atlantic Ocean.

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