Galford Gillian L, Soares-Filho Britaldo S, Sonter Laura J, Laporte Nadine
The Gund Institute for Ecological Economics, University of Vermont, 617 Main Street, Burlington, Vermont, 05405, United States of America.
Centro de Sensoriamento Remoto, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Belo Horizonte, 31270-901, Minas Gerais, Brazil.
PLoS One. 2015 Jun 24;10(6):e0128473. doi: 10.1371/journal.pone.0128473. eCollection 2015.
Central Africa's tropical forests are among the world's largest carbon reserves. Historically, they have experienced low rates of deforestation. Pressures to clear land are increasing due to development of infrastructure and livelihoods, foreign investment in agriculture, and shifting land use management, particularly in the Democratic Republic of Congo (DRC). The DRC contains the greatest area of intact African forests. These store approximately 22 billion tons of carbon in aboveground live biomass, yet only 10% are protected. Can the status quo of passive protection - forest management that is low or nonexistent - ensure the preservation of this forest and its carbon? We have developed the SimCongo model to simulate changes in land cover and land use based on theorized policy scenarios from 2010 to 2050. Three scenarios were examined: the first (Historical Trends) assumes passive forest protection; the next (Conservation) posits active protection of forests and activation of the national REDD+ action plan, and the last (Agricultural Development) assumes increased agricultural activities in forested land with concomitant increased deforestation. SimCongo is a cellular automata model based on Bayesian statistical methods tailored for the DRC, built with the Dinamica-EGO platform. The model is parameterized and validated with deforestation observations from the past and runs the scenarios from 2010 through 2050 with a yearly time step. We estimate the Historical Trends trajectory will result in average emissions of 139 million t CO2 year-1 by the 2040s, a 15% increase over current emissions. The Conservation scenario would result in 58% less clearing than Historical Trends and would conserve carbon-dense forest and woodland savanna areas. The Agricultural Development scenario leads to emissions of 212 million t CO2 year-1 by the 2040s. These scenarios are heuristic examples of policy's influence on forest conservation and carbon storage. Our results suggest that 1) passive protection of the DRC's forest and woodland savanna is insufficient to reduce deforestation; and 2): enactment of a REDD+ plan or similar conservation measure is needed to actively protect Congo forests, their unique ecology, and their important role in the global carbon cycle.
中非的热带森林是世界上最大的碳储备区之一。从历史上看，该地区的森林砍伐率一直较低。然而，由于基础设施建设和民生发展、农业领域的外国投资以及土地利用管理方式的转变，特别是在刚果民主共和国（简称“刚果（金）”），毁林压力正在不断增加。刚果（金）拥有非洲最大面积的原始森林。这些森林在地上活体生物量中储存了约220亿吨碳，但仅有10%得到了保护。消极保护的现状——森林管理水平低下或根本不存在——能否确保这片森林及其碳储量得到保护？我们开发了SimCongo模型，以根据2010年至2050年的理论政策情景模拟土地覆盖和土地利用的变化。研究了三种情景：第一种（历史趋势）假设森林为消极保护状态；第二种（保护）假定对森林进行积极保护并启动国家降排加行动计划；最后一种（农业发展）假设林地的农业活动增加，随之而来的是森林砍伐增加。SimCongo是一个基于贝叶斯统计方法的元胞自动机模型，专为刚果（金）量身定制，使用Dinamica-EGO平台构建。该模型根据过去的毁林观测数据进行参数化和验证，并以年为时间步长运行2010年至2050年的情景。我们估计，到2040年代，历史趋势轨迹将导致平均每年排放1.39亿吨二氧化碳，比当前排放量增加15%。保护情景下的森林砍伐量将比历史趋势减少58%，并将保护富含碳的森林和林地稀树草原地区。农业发展情景到2040年代将导致每年排放2.12亿吨二氧化碳。这些情景是政策对森林保护和碳储存影响的启发式示例。我们的结果表明：1）对刚果（金）的森林和林地稀树草原进行消极保护不足以减少森林砍伐；2）需要制定降排加计划或类似的保护措施，以积极保护刚果的森林及其独特生态，以及它们在全球碳循环中的重要作用。
