Is forest carbon sequestration at the expense of bioenergy and forest products cost-efficient in EU climate policy to 2050?

Forest management affects the quantity of CO₂ emissions in the atmosphere through carbon sequestration in standing biomass, carbon storage in forest products and production of bioenergy. The main question studied in this paper is whether forest carbon sequestration is worth increasing at the expense of bioenergy and forest products to achieve the EU emissions reduction target for 2050 in a cost-efficient manner. A dynamic cost minimisation model is used to find the optimal combination of carbon abatement strategies to meet annual emissions targets between 2010 and 2050. The results indicate that forest carbon sequestration is a low-cost abatement method. With sequestration, the net present costs of meeting EU carbon targets can be reduced by 23%.     

The potential and cost of increasing forest carbon sequestration in Sweden

This paper examines the potential and the cost of promoting forest carbon sequestration through a tax/subsidy to land owners for reducing/increasing carbon storage in their forests. We use a partial equilibrium model based on intertemporal optimization to estimate the impacts of carbon price (the tax/subsidy rate) on timber harvest volume and price in different time periods and on the change of forest carbon stock over time. The results show that a higher carbon price would lead to higher forest carbon stocks. The tax/subsidy induced annual net carbon sequestration is declining over time. The net carbon sequestration during 2015–2050 would increase by 30.2 to 218.3 million tonnes of CO₂, when carbon price increases from 170 SEK to 1428 SEK per tonne of CO₂. The associated cost, in terms of reduced total benefits of timber and other non-timber goods, ranges from 80 SEK to 105.8 SEK per tonne of CO₂. The change in carbon sequestration (as compared with the baseline case) beyond 2050 is small when carbon price is 680 SEK per tonne of CO₂ or lower. With a carbon price of 1428 SEK per tonne of CO₂, carbon sequestration will increase by 70 million tonnes of CO₂ from the baseline level during 2050-2070, and by 64 million tonnes during 2070–2170.     

Trade-offs between carbon sequestration and rural incomes in the N’hambita Community Carbon Project, Mozambique

This paper presents a preliminary assessment of trade-offs between carbon sequestration and farmers’ incomes from land-use systems implemented in a community-based project, in Mozambique. Systems either focus on carbon sequestration or combine sequestration with cash crop cultivation. The latter provide carbon payments with potential income from cash crop sales. Uncertainty about the future costs and benefits of maintaining and utilizing the land-use systems over time is addressed via application of Monte Carlo simulations. Our results show that compared with sequestration-only systems those that combine sequestration and cash crop production have higher net benefits, although they have less carbon-sequestration potential. Homestead planting provides the most attractive balance among competing policy goals. Carbon payments contribute to cash income and may enable smallholders to overcome initial project investment costs.     

Soil CO2 emission and carbon budget of a wheat/maize annual double-cropped system in response to tillage and residue management in the North China Plain

To investigate the impacts of tillage and crop residue managements on soil CO₂ emission and C budget in a wheat (Triticum aestivum L.)/maize (Zea mays L.) double-cropped system in the North China Plain (NCP), a field experiment was conducted consisting of four treatments: tillage with crop residues retention (CT+), tillage with crop residues removal (CT?), no-till with crop residues retention (NT+), and no-till with crop residues removal (NT?). Daily soil CO₂ fluxes changed with crop growing stage and peaked during the most vigorous growth of period, fluxes in maize season were higher than those in wheat season. Compared to the tilled soils, cumulative CO₂ emissions were significantly lower under no-till treatments. The largest cumulative CO₂ emission occurred under CT+ (65?g CO₂-C m^?2 y^?1) and the smallest was under NT+ (39?g CO₂-C m^?2 y^?1). After 5 years of the experiment, soil organic carbon (SOC) sequestration were greater with crop residues retention (CT+ and NT+) than with crop residues removal (CT? and NT?), the maximum SOC stock was in NT+ (5940?g C m^?2) while the minimum was in CT? (3635?g C m^?2). NT+ could help to mitigate CO₂ emission in the annual wheat/maize double-cropping system of the area.     

Logs or permits? Forestry land use decisions in an emissions trading scheme

Negative carbon emissions options are required to meet long-term climate goals in many countries. One way to incentivise these options is by paying farmers for carbon sequestered by forests through an emissions trading scheme (ETS). New Zealand has a comprehensive ETS, which includes incentives for farmers to plant permanent exotic forests. This research uses an economy-wide model, a forestry model and land use change functions to measure the expected proportion of farmers with trees at harvesting age that will change land use from production to permanent forests in New Zealand from 2014 to 2050. We also estimate the impacts on carbon sequestration, the carbon price, gross emissions, GDP and welfare. When there is forestry land use change, the results indicate that the responsiveness of land owners to the carbon price has a measured impact on carbon sequestration. For example, under the fastest land use change scenario, carbon sequestration reaches 29.93 Mt CO₂e by 2050 compared to 23.41 Mt CO₂e in the no land use change scenario (a 28% increase). Even under the slowest land use change scenario, carbon sequestration is 25.89 Mt CO₂e by 2050 (an 11% increase compared with no land use change). This is because, if foresters decide not to switch to permanent forests in 1 year, carbon prices and ultimately incentives to convert to permanent forests will be higher in future years.     

The assessment of the impact of oil palm and rubber plantations on the biotic and abiotic properties of tropical peat swamp soil in Indonesia

Current intensification of agricultural activities in Indonesia has led to increased use of tropical peat swamp forests for agriculture. Ideally, peat swamp ecosystems should not be disturbed as they provide essential services such as soil erosion control, ecosystem stabilization and moderation of climate and energy fluxes as well as reducing carbon emission and conserving biodiversity. In this study, agricultural land from Giam Siak Kecil–Bukit Batu Biosphere Reserve in Indonesia was evaluated to assess the impact of oil palm (burning and without burning) and rubber (5–10 and >40 years old) plantations on soil properties through comparisons with soils from a natural forest (NF). Substantial changes in the physico-chemical properties of soils from both plantations were observed including significant reductions in soil organic matter (4–18%) and water holding capacity (22–53%), but an increase in bulk density (ρb) (0.08–0.17?g?cm^?3). A significant increase in bacterial biomass was also observed following conversion of the NF to plantation (p<0.05). However, the oil palm plantation (OPP) (without burning) showed reduced microbial activities and the lowest Shannon diversity values (2.90) compared to other samples. Community-level physiological profiling showed impaired community function only in soils from the OPP but higher CO₂ exchange rates in most plantation soils. Soils from the rubber plantation (RP) were less impaired in terms of their natural function and therefore RPs appeared to be more suitable for sustainable agricultural use than OPP.     

An open-access method for targeting revegetation based on potential for emissions reduction,carbon sequestration and opportunity cost

We propose a simple heuristic that uses open-access models and government data on agricultural activities to estimate total carbon emissions from agriculture, the gross carbon benefit and the opportunity cost per tonne CO₂-e from revegetating to environmental plantings or plantation forestry. We test this across ten areas of mixed land-use that represent diverse Australian agricultural systems along a rainfall transect. The local value of agricultural production was obtained from government statistics and used to estimate the current economic opportunity cost of converting cleared agricultural land to mixed environmental plantings for carbon sequestration. Gross carbon benefit from revegetation was closely related to current agricultural use, as was financial opportunity cost. These were not related simply to site productivity potential or rainfall. The proportion of land cleared for agriculture that would need to be re-vegetated to achieve a localised zero-carbon land-use scenario was calculated by the ratio of current agricultural emissions to gross carbon benefit from revegetation; this ranged from 13% to 66% for groups of agricultural industries across Australian rainfall transects. While the heuristic does not capture the detail of models built specifically for local research questions it does provide a different lens on the questions policy makers and land managers may ask about the costs and benefits of revegetating agricultural land, and provides open-access methods to guide them.     

Missing the forest for the data? Conflicting valuations of the forest and cultivable lands

In reaction to Greenpeace campaigns denouncing the impact of oil palm plantations in Southeast Asia, Golden Agri-Resources (GAR) – a major actor in the palm oil sector – adopted a zero-deforestation policy. The implementation of this policy raised a simple, albeit tricky, question: what is a forest? In response, Greenpeace, GAR and a consultancy firm developed a methodology for forest classification called the High Carbon Stock (HCS) Approach. Employing a vegetation classification based primarily on a threshold of carbon sequestration, the method identifies which forested zones to protect from conversion to agriculture. While currently gaining resonance in the realm of sustainability standards, its implementation in Indonesia and Liberia encountered resistance and criticism by rural dwellers and social NGOs. How did HCS advocates integrate local peoples’ concerns, interests and claims to compose commonality? By analysing the HCS methodology's content, implementation and progressive adaptation, this article shows how HCS advocates favoured a specific mode of composition: one that fits a liberal grammar and that has specific implications on the valuation of forest and cultivable lands. The HCS approach is thus more than a data collection tool; it encapsulates and reinforces a particular vision of the environment and how people should relate to it.     

Agriculture's Likely Role in Meeting Canada's Kyoto Commitments*

Voluntary adoption of beneficial management practices will be the primary means by which farmers cut net greenhouse gas (GHG) emissions. The offset system will not be a major driver due to (a) the relatively low prices likely to be offered by large final emitters facing an emission cap, (b) discounts applied to those prices for temporary sequestration, (c) the transaction costs and risk premiums associated with signing carbon contracts, and (d) the low elasticity of supply of CO₂ abatement. Although Canadian farmers are likely to participate to only a limited extent in the carbon‐offset market, many will find it profitable to adopt one or more of the BMPs for reducing net GHG emissions. Canadian agriculture is likely to contribute significantly to net emission reductions by voluntarily sequestering carbon due to the adoption of zero till in the last decade, and possibly by cutting fertilizer levels in the next decade. The contribution will be mainly a response to meeting personal economic objectives rather than being induced by direct incentives through the offset program.     

Forest carbon benefits,costs and leakage effects of carbon reserve scenarios in the United States

This study evaluated the potential effectiveness of future carbon reserve scenarios, where U.S. forest landowners would hypothetically be paid to sequester carbon on their timberland and forego timber harvests for 100 years. Scenarios featured direct payments to landowners of $0 (baseline), $5, $10, or $15 per metric ton of additional forest carbon sequestered on the set aside lands, with maximum annual expenditures of $3 billion. Results indicated that from 1513 to 6837 Tg (Teragrams) of additional carbon (as carbon dioxide equivalent, CO₂e) would be sequestered on U.S. timberlands relative to the baseline case over the next 50 years (30–137 Tg CO₂e annually). These projected amounts of sequestered carbon on timberlands take into account projected increases in timber removal and forest carbon losses on other timberlands (carbon leakage effects). Net effectiveness of carbon reserve scenarios in terms of overall net gain in timberland carbon stocks from 2010 to 2060 ranged from 0.29 tCO₂e net carbon increase for a payment of $5/tCO₂e to the landowner (71% leakage), to 0.15 tCO₂e net carbon increase for a payment of $15/tCO₂e to the landowner (85% leakage). A policy or program to buy carbon credits from landowners would need to discount additions to the carbon reserve by the estimated amount of leakage. In the scenarios evaluated, the timber set-asides reduced timberland area available for harvest up to 35% and available timber inventory up to 55%, relative to the baseline scenario over the next 50 years, resulting in projected changes in timber prices, harvest levels, and forest product revenues for the forest products sector.     

Consequences of carbon offset payments for the global forest sector

Long-term effects of policies to induce carbon storage in forests were projected with the Global Forest Products Model. Offset payments for carbon sequestered in forest biomass of $15–$50/t CO₂e applied in all countries increased CO₂ sequestration in world forests by 5–14 billion tons from 2009 to 2030. Limiting implementation to developed countries exported environmental damage from North to South, as developing countries harvested more, decreasing their stored CO₂e. Substantially more CO₂e was sequestered by allocating a given budget to all countries rather than to developed countries only. As offset payments increased wood prices relatively more than they decreased production, timber revenues generally increased. In the few countries with timber revenues losses they were more than compensated by the offset payments.     

Differential livelihood impacts of oil palm expansion in Indonesia

In this article, the impacts of oil palm adoption on livelihoods of smallholder farm households are analyzed. The study builds on survey data from Sumatra, Indonesia. Treatment‐effects and endogenous switching regression models suggest that smallholder households benefit from oil palm adoption on average. Part of the benefit stems from the fact that oil palm requires less labor than rubber, the main alternative crop. This allows oil palm adopters to allocate more labor to off‐farm activities and/or to expand their farmland. For households with a low land‐to‐labor ratio, rubber is typically a more lucrative crop than oil palm. Depending on various social and institutional factors, households’ access to land, labor, and capital varies, contributing to impact heterogeneity. Welfare gains associated with oil palm are more pronounced among households that have formal land titles and access to additional land to expand their farm size during the process of adoption.     

Assessment of land use and land cover changes and valuation of carbon stocks in the Sergipe semiarid region,Brazil: 1992–2030

The semiarid region in the state of Sergipe, Brazil, approximately 11,000 km², has experienced high deforestation rates in the last decades, which ultimately contribute to global climatic changes. The valuation of ecosystem services of CO₂ sequestration can support definition of environmental policies to decrease deforestation in that region. This study aimed to assess land use and land cover changes in the Sergipe semiarid region between 1992 and 2017 by applying remotely sensed data and technics; simulate the land use and land cover changes between 2017 and 2030 by applying a cellular automaton model, by assuming current land use trends (Business as Usual – BAU) as a reference scenario, and a more conservative scenario (Protected Forest – PF), in which was assumed an effective enforcement of the Brazilian Forest Code established in 2012; simulate the carbon stocks by 2017 assuming the BAU and PF scenarios by 2030, and estimate the Carbon balance between the 2030 and 2017 scenarios; and estimate the economic valuation of carbon emission and sequestration by using the InVEST software. The results showed that agriculture (cropped lands) was main driver of the landscape changes in the study area, which increased 14% by 2017, a net increase of 1494.45 km². The results showed that the total Carbon emissions would reach 736,900 Mg CO₂-eq by assuming the BAU scenario, which would increase the cost of opportunity up to US$ 17.7 million and a social carbon cost varying between US$ 10.3 and US$ 30.2 million. The restoration of the permanent preservation areas could contribute to increase Carbon sequestration up to 481,900 Mg CO₂-eq by 2030, which is equivalent cost of US$ 11.6 million. The natural landscape in the Sergipe semiarid region was strongly affected by deforestation activities occurred between 1992 and 2017. It requires, therefore, effective actions to support and promote restoration of degraded areas. The forested areas within the Sergipe semiarid region were the most affected type of vegetation because of expansion of agricultural fields soil exposures (Exposed Land). Environmental assessments based on scenarios and economic valuations can provide crucial information to support policy and decision makers to improve strategies for environmental management and conservation.     

广东省森林碳汇量估算及其空间效应分析

文章选用蓄积量换算因子法和CO2FIX v3.2模型,分别用于估算广东省现有森林的静态碳汇储量和新造林动态碳汇潜力,并利用空间计量Moran I指数分析广东省碳汇布局的空间效应,为广东碳交易市场发展及其CDM造林碳汇项目的开展提供决策依据。研究表明:2010年广东省全省碳汇总量为481.34Tg C,;在假设进行轮伐的情况下,2008~2057年间广东省实现的新造林净固碳量为97.38Tg C;其中粤北地区碳汇储量和碳汇潜力最高,珠三角地区碳汇储量及碳汇潜力最低。空间效应分析显示了广东省碳汇布局存在较强的空间正相关,大部分城市地区的碳汇储量及潜力处于高-高集群或者低-低的集群中,空间集群特征客观存在。结论表明,应充分考虑到碳汇空间的分布特性,考虑到不同地区碳汇储量及潜力之间的关系,将森林碳汇纳入广东碳排放权交易体系,开展跨区合作,从而实现广东省减排成本的最小化和区域碳排放平衡。     

Gliricidia sepium Carbon Inputs and Soil Carbon Pools in a Costa Rican Alley Cropping System

Alternative land management practices, including agroforestry, help to maintain levels of soil organic matter (SOM) and can facilitate soil carbon (C) sequestration for mitigating atmospheric CO₂ emissions. This study quantified C inputs and determined the changes of the soil C pool in a 19-year-old Gliricidia sepium alley cropping system, studied at two fertiliser levels (tree prunings only [? N], and tree prunings plus chicken manure [+ N]), and was compared to a sole crop system. Carbon input from tree prunings ranged from 455 to 457 g C m^{? 2} y^{? 1}, whereas C inputs from crop residues were similar between alley- and sole crops ranging from 121 to 159 g C m^{? 2}y^{? 1}. The soil organic C (SOC) pool in the alley crop was 16–23% higher than the sole crop. In the 19th year of alley farming, SOC was significantly higher (p < 0.05) in the alley crop (3.2%) compared to the sole crop (2.4%), and was also greater compared to that at the time of establishment of the agroforestry system (2.8%). Gross SOC turnover to a 20-cm depth ranged from 12 to 14 years in the + N and ?N alley crops compared to 49 and 50 years in the + N and ?N treatments for the sole crops. Residue stabilisation efficiency in the alley crops was 39% and 55% in + N and ?N treatments respectively.     

农业保险对农业固碳增效的影响及机制研究

[目的]探究农业保险通过改变农户生产行为,进而影响农业固碳效果的作用路径。[方法]文章基于2008—2019年中国30个省（市、自治区,不含港澳台和西藏）的种植业数据,构建有调节的并行多重中介效应模型,分析农业保险发展水平对农业净碳汇的作用机制。[结果]（1）从总体来看,当前农业保险的发展抑制了农业固碳效果,具体表现为农业保险增加了农业碳排放,而对农业碳吸收没有显著影响;（2）农业保险对农业净碳汇的影响有两条路径,一是农业保险通过提升种植专业化水平促进农业净碳汇,二是农业保险通过促进农业技术进步抑制农业净碳汇,但环境规制会削弱农业技术进步对农业净碳汇的抑制作用;（3）在异质性分析中,西部农业保险发展的农业固碳效果要好于东部,中部农业保险发展对农业固碳效果没有显著影响。[结论]（1）提高对专业化规模生产主体的农业保险保费补贴比例,以放大农业保险对农业净碳汇的促进作用;（2）设计绿色农业产品保险,引导农业生产者从事绿色农业生产经营,减少一般机械投入对农业净碳汇产生的负向影响;（3）提高农业保险政策与环境保护政策的配合程度,在发展农业保险的同时,加强农业环境保护政策的执行力度。     

基于情景分析的烟草种植替代综合效应研究

[目的]烟草种植替代是从源头控制烟草消费的最有效措施,但在我国还未全面实施。文章分析研究不同情境下烟草种植替代可能产生的综合效应,以期推动我国烟草种植替代的实施。[方法]基于2018年湖北省利川市11种作物的成本收益、化肥使用量等数据,利用情景分析法,结合环境风险指数法和综合评价法对烟草种植替代可能产生的综合效应进行分析。[结果]（1）种植烟草高昂的人工成本使得其净利润为负,且在11种作物中最低,其现金收益仅高于粮食与油料作物,种植番茄或黄瓜的现金收益分别比烟草高7倍和6倍,烟草较高的价格可能是吸引农户种植的主要原因之一;（2）情景1种植烟草的氮肥使用环境风险较低,磷肥与钾肥使用的环境风险等级较高;情景2种植粮食作物可以减少化肥使用的环境风险,种植蔬菜等作物会增加化肥使用的环境风险;（3）在该文的3种情景中,粮食作物的固碳能力较强,经济作物的固碳能力较弱;种植烟草的固碳能力最弱,其综合效应仅优于油菜籽与烟草的组合,远低于种植蔬菜或烟草与蔬菜作物组合种植的综合效应。[结论]利川市可以选择番茄、黄瓜等蔬菜作物或是这些作物与烟草共同种植的方案来代替烟草种植,在履行《烟草控制框架公约》的同时能...     

中国农作物碳足迹核算研究概述

[目的]碳足迹核算是对农业温室气体排放的定量评价,开展农作物碳足迹核算理论研究能够为低碳农业建设提供技术支撑。[方法]文章在对我国农资投入变化情况进行简要分析的基础上,从碳足迹概念,碳足迹核算的数据来源、方法,我国农作物碳足迹核算涉及的对象、系统边界以及构成、时空分布特征等方面,系统总结了当前农作物碳足迹核算的研究进展。[结果](1)目前我国已开展碳足迹核算的农作物主要有水稻、玉米、小麦、大豆、油菜、脐橙、苹果、油菜和烟叶等,研究过程中活动水平数据、温室气体排放参数来源和核算包含过程的不尽相同,核算过程有仅针对研究对象生产环节的,也有包含上游环节和生产环节的,部分研究还包括产品加工、运输分销、消费和废弃环节,因此核算结果差异较大。(2)研究表明,肥料尤其是氮肥的施用和灌溉耗电是小麦和玉米生产温室气体排放的主要来源,稻田CH₄排放是水稻最主要的排放源,肥料施用和施肥后田间N₂O排放是棉花、花生、大豆、油菜和水果等的温室气体排放的主要来源。(3)同时,受农资投入、耕作方式和技术手段等影响,农作物的碳足迹是不断变化的。[结论]农作物碳足迹核算研究需...     

Forest or oil palm plantation? Interpretation of local responses to the oil palm promises in Kalimantan,Indonesia

Global land use/land cover change is dominated by the expansion of cash crops plantations, replacing natural ecosystems including forests. International trade is an important factor in this process. Increasing demand on certain crops has triggered plantation expansion and deforestation, and influence local land use in other countries (land teleconnections). Oil palm expansion is one of the most prominent examples of land teleconnections. In Indonesia, oil palm plantations area increased from 1.1 million ha in 1990 to 11.2 million ha in 2015. According to the Indonesian Law on Plantation, the indigenous people's decisions play important roles in land use decisions. This paper investigates what were the factors (drivers) determining the individual-level responses to the oil palm promises in West Kalimantan. These questions are not only important for the future of Kalimantan’s rainforest but will also enrich deforestation and conservation-development discourses. We selected 49 respondents for interviews and focus groups such that people who opposed and people who supported the conversion were both well represented. Much attention was paid to arrive at a balanced set of operational variables, such as the economic resilience, agency and embeddedness of actors and the degree to which actors had appreciated and believed the oil palm promise. Data were analyzed through the QCA method. The outcomes show a perfect association of appreciation of the oil palm promises, belief in them and the decision to support the oil palm. This was not strongly associated with low economic resilience however; economically less resilient respondents could reject the oil palm conversion, while economically resilient respondents could support it. In other words, the data do not point to a poverty/deforestation nexus. Rather, the data suggest the existence of an ‘embeddedness / rejection nexus’; people that were well-connected to community, traditions and nature held long-term motivations and rejected the oil palm promise, and vice versa. More attention to this phenomenon will help bridge conservation-development objectives in Kalimantan.     

森林碳汇价值与农户林业收入增长的分析

根据福建省顺昌县农户林业收入的调查数据,从林产品收入、林业服务性收入、林地地租收入、生态公益林补偿收入、其他涉林收入等方面对农户林业收入构成进行分析,发现森林生态效益在农户林业收入中的贡献非常小,仅占0.18%;以现有碳汇市场为参考,通过森林蓄积量换算因子法估算出该县的森林碳汇量及其碳汇价值,指出森林碳汇价值的实现可以有效地增加农户林业生态收入、改善农户的林业收入结构;并探讨了农户森林碳汇价值实现的途径。