{ "document_id": 16694, "page": 1, "width_pt": 594, "height_pt": 756, "rotation": 0, "pipeline_version": "paddleocr-vl-1.6+paul-48", "engine": "paddleocr_vl", "source_run_id": 16805, "item_count": 27, "counts_by_type": { "footer": 2, "footnote": 3, "header": 1, "heading": 3, "link": 1, "text": 16, "title": 1 }, "build_ms": 9, "items": [ { "id": "p1.1", "order": 1, "type": "header", "bbox": { "l": 33.36, "t": 726.96, "r": 281.76, "b": 714.72 }, "text": "SCIENCE ADVANCES | RESEARCH ARTICLE", "attrs": { "block_label": "header" }, "level": 2 }, { "id": "p1.2", "order": 2, "type": "text", "bbox": { "l": 33.84, "t": 698.16, "r": 95.76, "b": 687.84 }, "text": "BIOENERGY" }, { "id": "p1.3", "order": 3, "type": "title", "bbox": { "l": 33.84, "t": 679.92, "r": 404.64, "b": 642.72 }, "text": "Forests: Carbon sequestration, biomass energy, or both?", "attrs": { "block_label": "doc_title" }, "level": 2 }, { "id": "p1.4", "order": 4, "type": "text", "bbox": { "l": 33.36, "t": 633.36, "r": 264.24, "b": 620.88 }, "text": "Alice Favero[p1.4.1], Adam Daigneault[p1.4.2], Brent Sohngen [p1.4.3]", "children": [ { "id": "p1.4.1", "order": 5, "type": "text", "bbox": { "l": 33.36, "t": 633.36, "r": 264.24, "b": 620.88 }, "text": "¹", "attrs": { "inline": true, "text_offset": 12, "text_span": 8, "bbox_estimated": true } }, { "id": "p1.4.2", "order": 6, "type": "text", "bbox": { "l": 33.36, "t": 633.36, "r": 264.24, "b": 620.88 }, "text": "^{2*}", "attrs": { "inline": true, "text_offset": 37, "text_span": 8, "bbox_estimated": true } }, { "id": "p1.4.3", "order": 7, "type": "text", "bbox": { "l": 33.36, "t": 633.36, "r": 264.24, "b": 620.88 }, "text": "³", "attrs": { "inline": true, "text_offset": 61, "text_span": 8, "bbox_estimated": true } } ] }, { "id": "p1.5", "order": 8, "type": "text", "bbox": { "l": 33.84, "t": 611.04, "r": 472.56, "b": 515.76 }, "text": "There is a continuing debate over the role that woody bioenergy plays in climate mitigation. This paper clarifies this controversy and illustrates the impacts of woody biomass demand on forest harvests, prices, timber management investments and intensity, forest area, and the resulting carbon balance under different climate mitigation policies. Increased bioenergy demand increases forest carbon stocks thanks to afforestation activities and more intensive management relative to a no-bioenergy case. Some natural forests, however, are converted to more intensive management, with potential biodiversity losses. Incentivizing both wood-based bioenergy and forest sequestration could increase carbon sequestration and conserve natural forests simultaneously. We conclude that the expanded use of wood for bioenergy will result in net carbon benefits, but an efficient policy also needs to regulate forest carbon sequestration.", "attrs": { "block_label": "abstract" } }, { "id": "p1.6", "order": 9, "type": "heading", "bbox": { "l": 33.84, "t": 488.88, "r": 101.04, "b": 479.52 }, "text": "INTRODUCTION", "attrs": { "block_label": "paragraph_title" }, "level": 3 }, { "id": "p1.7", "order": 10, "type": "text", "bbox": { "l": 32.88, "t": 478.32, "r": 293.04, "b": 334.8 }, "text": "A long literature establishes that forests are an efficient carbon sink through actions such as afforestation, forest management, and reduced deforestation (1–5). In recent years, forest-based actions have gained additional policy relevance as many countries have included forest sequestration activities in their nationally determined contributions toward reducing net carbon emissions as part of the Paris Agreement (6, 7). At the same time, there have been increasing efforts in the United States and Europe to use wood as a source of biomass energy, under the assumption that wood-based energy is “carbon neutral” (8, 9). Last, most pathways that aim to restrict global average temperature to 1.5°C by 2100 rely on large-scale deployment of afforestation actions and biomass used in power plants with carbon capture and storage (BECCS) (10)." }, { "id": "p1.8", "order": 11, "type": "text", "bbox": { "l": 33.12, "t": 335.52, "r": 293.04, "b": 91.92 }, "text": "The role that forests should play in mitigating climate change is still widely debated. Some researchers have argued that forest-based biomass energy is not carbon neutral (11–13) and, thus, that forest-based bioenergy should not be allowed to offset other energy sources under renewable energy standards. These assessments have suggested that when forest biomass energy is generated, it creates a carbon emission to the atmosphere that may, or may not, be taken back up by trees that grow in the future. Even if regrowth does occur, it occurs slowly over time, increasing global climate damages during the period when the released carbon is in the atmosphere. Given these concerns, some have argued that society should focus on enhancing carbon sinks rather than encouraging biomass energy (11, 13–15). Assessing whether forest biomass energy is carbon neutral is complex and sensitive to assumptions about the spatial and temporal scale of the analysis, feedstocks used, and supply chain emissions. Buchholz et al.'s (16) meta-analysis found that the payback period (i.e., the time required by the forest to recover through sequestration the carbon dioxide from biomass combusted for energy) ranged from zero to more than 1000 years. Birdsey et al. (17) conclude that increasing bioenergy production and pellet exports often increases net emissions of greenhouse gases (GHGs) for decades or longer, depending on source of feedstock and its alternate fate, time horizon of analysis, energy emissions associated with the supply chain and fuel substitution, and impacts on carbon cycling of forest ecosystems. The studies examined in these two reviews, however, ignore economic analysis that accounts for the interactions between demand and supply and forest management (18–23). These interactions include assessment of the opportunity costs of intensified harvesting and management, as well as expansion of intensive timber harvesting activities into extensive (e.g., unmanaged) regions." }, { "id": "p1.9", "order": 12, "type": "text", "bbox": { "l": 299.76, "t": 489.12, "r": 559.92, "b": 400.8 }, "text": "energy emissions associated with the supply chain and fuel substitution, and impacts on carbon cycling of forest ecosystems. The studies examined in these two reviews, however, ignore economic analysis that accounts for the interactions between demand and supply and forest management (18–23). These interactions include assessment of the opportunity costs of intensified harvesting and management, as well as expansion of intensive timber harvesting activities into extensive (e.g., unmanaged) regions." }, { "id": "p1.10", "order": 13, "type": "text", "bbox": { "l": 299.52, "t": 401.04, "r": 559.92, "b": 223.44 }, "text": "This paper examines key issues related to the consequences of bioenergy policies on forests and carbon emissions, namely, management response, the efficiency of the policy, and the impacts of increasing biomass demand on forest ecosystem services. To analyze these issues, we use a dynamic global forest model that accounts for the biological and economic responses to various policy incentives on forest management and carbon fluxes in all regions of the world (22, 23). Such integrated assessment modeling of the forest sector provides important insights into the temporal and spatial scale of forest management efforts that must be undertaken to increase wood flow in the face of large, new biomass energy demands, as well as their interactions with carbon policies. The analysis clarifies how various policy incentives for biomass energy and carbon sequestration influence the net exchange of carbon between the atmosphere and forested ecosystems. Last, a sensitivity analysis tests the results under different assumptions on land constraints and economic parameters." }, { "id": "p1.11", "order": 14, "type": "heading", "bbox": { "l": 300.96, "t": 203.28, "r": 340.56, "b": 193.44 }, "text": "RESULTS", "attrs": { "block_label": "paragraph_title" }, "level": 3 }, { "id": "p1.12", "order": 15, "type": "heading", "bbox": { "l": 300, "t": 192.24, "r": 497.28, "b": 181.68 }, "text": "The debate behind woody biomass for energy", "attrs": { "block_label": "paragraph_title" }, "level": 3 }, { "id": "p1.13", "order": 16, "type": "text", "bbox": { "l": 299.76, "t": 180.48, "r": 560.64, "b": 47.76 }, "text": "Three critical issues have arisen in the literature related to the use of woody biomass for energy. First, the impact of biomass energy policies on carbon depends on the supply response, which includes investments in new forests, increased management of existing forests, harvests of inaccessible and unmanaged forests in the extensive margin, conversion of those forests to more intensive uses, and substitution across product uses. Studies that assume there is little to no management response, or consider only use of the extensive margin, predict that bioenergy demand will increase carbon emissions (16, 17). Studies that allow efficient investments in forestry management find that bioenergy policies lead to a net increase in forest sequestration (18–22). A key determinant rests on the response of land use and management." }, { "id": "p1.14", "order": 17, "type": "text", "bbox": { "l": 572.88, "t": 501.84, "r": 583.44, "b": 256.08 }, "text": "Downloaded from http://advances.sciencemag.org/ on June 25, 2020", "attrs": { "block_label": "aside_text" }, "children": [ { "id": "p1.14.1", "order": 18, "type": "link", "bbox": { "l": 574, "t": 436.152, "r": 584, "b": 318.984 }, "text": "http://advances.sciencemag.org/", "attrs": { "uri": "http://advances.sciencemag.org/", "action_type": "/URI" } } ] }, { "id": "p1.15", "order": 19, "type": "footnote", "bbox": { "l": 488.4, "t": 695.28, "r": 559.92, "b": 566.4 }, "text": "Copyright © 2020\nThe Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).", "attrs": { "block_label": "vision_footnote" } }, { "id": "p1.16", "order": 20, "type": "footnote", "bbox": { "l": 33.12, "t": 75.6, "r": 291.6, "b": 57.12 }, "text": "[p1.16.1]Georgia Institute of Technology, Atlanta, GA, USA. [p1.16.2]University of Maine, Orono, ME, USA. [p1.16.3]Ohio State University, Columbus, OH, USA.", "attrs": { "block_label": "footnote" }, "children": [ { "id": "p1.16.1", "order": 21, "type": "text", "bbox": { "l": 33.12, "t": 75.6, "r": 291.6, "b": 57.12 }, "text": "¹", "attrs": { "inline": true, "text_offset": 0, "text_span": 9, "bbox_estimated": true } }, { "id": "p1.16.2", "order": 22, "type": "text", "bbox": { "l": 33.12, "t": 75.6, "r": 291.6, "b": 57.12 }, "text": "²", "attrs": { "inline": true, "text_offset": 60, "text_span": 9, "bbox_estimated": true } }, { "id": "p1.16.3", "order": 23, "type": "text", "bbox": { "l": 33.12, "t": 75.6, "r": 291.6, "b": 57.12 }, "text": "³", "attrs": { "inline": true, "text_offset": 106, "text_span": 9, "bbox_estimated": true } } ] }, { "id": "p1.17", "order": 24, "type": "footnote", "bbox": { "l": 34.08, "t": 57.84, "r": 226.56, "b": 48 }, "text": "[p1.17.1]Corresponding author. Email: adam.daigneault@maine.edu", "attrs": { "block_label": "footnote" }, "children": [ { "id": "p1.17.1", "order": 25, "type": "text", "bbox": { "l": 34.08, "t": 57.84, "r": 226.56, "b": 48 }, "text": "^{*}", "attrs": { "inline": true, "text_offset": 0, "text_span": 9, "bbox_estimated": true } } ] }, { "id": "p1.18", "order": 26, "type": "footer", "bbox": { "l": 34.08, "t": 38.4, "r": 215.28, "b": 29.28 }, "text": "Favero et al., Sci. Adv. 2020; 6: eaay6792 25 March 2020", "attrs": { "block_label": "footer" } }, { "id": "p1.19", "order": 27, "type": "footer", "bbox": { "l": 534.24, "t": 37.92, "r": 559.2, "b": 29.28 }, "text": "1 of 13", "attrs": { "block_label": "number" } } ], "excluded_furniture": { "first": [], "last": [] } }