Dual discounting in climate change mitigation in the forest sector

The efficiency of potential climate change mitigation is predicated on future costs and benefits and thus heavily influenced by the discount scheme. Dual discounting involves discounting carbon and monetary values differently; stand level modeling efforts show that it improves the profitability of afforestation projects. However, these stand level results may not hold across other age classes and stocking levels. Using a partial, spatial equilibrium model of the Norwegian forest sector, we analyze the impacts of a dual discounting scheme on climate change mitigation efforts. Dual discounting results in less mitigation efforts in the first decades but substantially higher long-term mitigation efforts.     

Carbon mitigation potential of the French forest sector under threat of combined physical and market impacts due to climate change

Objectives(1) To quantify the contribution of the French forest-wood product chain in terms of carbon sequestration and substitution when accounting for both the physical impacts (shifts in tree growth and mortality rates) and the market impacts (increased demand of harvested wood products (HWP)) of climate change (cc) and the subsequent forest managers adaptations; (2) To assess the uncertainty of the impacts on the above carbon balance and on forest allocation; and (3) To assess the role of managers’ expectations toward these future, uncertain but highly anticipated, impacts.MethodologyWe used a bio-economic model of the French Forest Sector (FFSM++) that is able to consider and integrate: (a) the effects of climate change over forest dynamics; (b) forest investment decisions (among groups of species) according to expected profitability; and (c) market effects in terms of regionalised supply, consumption and trade of HWP, depending on the forest resource stocks and international prices. By including both forest dynamics and forest products, we can evaluate the carbon balance taking the following elements into consideration: (a) carbon sequestered in live and dead biomass in the forest; (b) carbon sequestered in HWP; (c) carbon substituted when wood is used in place of fossil fuels or more energy-intensive materials; and (d) carbon released by forest operations.ResultsWhen the model is run at constant conditions for the next century, the average carbon potential of French forests is 66.2–125.3 Mt CO₂ y⁻¹, depending on whether we consider only inventoried wood resources, HWP pools and direct energy substitution, or if we also account for the carbon stored in tree branches and roots and if we consider the more indirect, but also largely more subjective, material substitution. These values correspond to 18.3% and 34.7%, respectively, of the French 2010 emissions (361 Mt CO₂). However, when we consider both the probable increment of coniferous mortality and changes in forest growth, plus the rise in HWP demand worldwide, the average sequestration rate of the French forest decreases by 6.6–5.8% to 61.8–118.0 Mt CO₂ y⁻¹. Running partial scenarios, we can assess the relative interplay of these two factors, where the price factor increases the HWP stock while decreasing the forest stocks (where the latter effect prevails), while the physical impact of climate change reduces both, but to a lesser extent. Considering short-sighted forest managers, whose behaviour is based uniquely on the observed conditions at the time decisions are made, we obtain a limited effect of the overall carbon balance but a relatively large impact on the area allocation of broadleaved vs. coniferous species.     

National urban land-use/cover change since the beginning of the 21st century and its policy implications in China

China has experienced rapid urban expansion since the beginning of the 21^st century. Although many previous studies have explored the forces driving urbanization, how policies drive these changes at the national scale has not been fully examined. This research aims to delineate the regional differentiations of urban expansion and related impervious surface area (ISA) density and reveal the socioeconomic and macropolicy factors causing these changes. The result shows that national urban land expanded from 4.26 × 10⁴ km² in 2000 to 6.90 × 10⁴ km² in 2015 at an unprecedented rate, with an average increasing rate of 1760 km²/yr since 2000. The spatial metrics of ISA density diverted from a low-density sprawl mode during 2000–2010 to a dense expansion mode during 2010–2015, with the highest ISA density of 70.70% in 2015. Regionally, the rate of urban expansion and ISA growth reduced in the coastal zone in 2010–2015. In contrast, urban expansion accelerated in the western and central zones, due to the China Western Development Plan and the Rise of Central China Plan initiated in 1999 and 2006, respectively. Although the concept of “Sponge city” (an urban water management system) was proposed in 2013, the national ISA density still increased due to urban infilling. The overarching issue that must be seriously considered is the tradeoff between the magnitude of urban expansion and ISA density and building sustainable and livable cities in an era of urban transformation.     

Controlling deforestation in the Brazilian Amazon: Regional economic impacts and land-use change

Brazil confirmed targets for reducing greenhouse gas emissions in 2008, including an 80% reduction in deforestation in the Amazon by 2020. With this in mind, we investigated the trade-off between environmental conservation and economic growth in the Amazon. The aim of this study is to project the economic losses and land-use changes resulting from a policy to control deforestation and the rise in land productivity that is necessary to offset those losses. We developed a Dynamic Interregional Computable General Equilibrium Model for 30 Amazon regions with a land module allowing conversion between types of land. The results have shown that the most affected regions would be soybeans and cattle producers as well as regions dominated by family farms. To offset these impacts, it was estimated that an annual gain of land productivity of approximately 1.4% would be required.     

Informal settlements’ needs and environmental conservation in Mexico City: An unsolved challenge for land-use policy

The aim of this article is to analyze the effectiveness of land-use policy in Mexico City in controlling the expansion of informal human settlements in peri-urban zones of high ecological value. It is argued that Mexico City's land-use policy has been reactive and internally inconsistent, failing to take informal settlements into account, has not offered the poor access to housing with adequate services and greater security in terms of land tenure, and lacks the necessary financial resources and institutional capabilities for providing solutions to these problems. Through a case study of informal settlement management policy in the Tlalpan Delegation,¹ applied in what has been termed SC or “Conservation Land,”² we conclude that local government exhibits an inability to confront the new challenge of urban sustainability, that it resorts to conventional solutions which give rise to contradictory situations where political decision-making prevails over ecological considerations, so land-use policy is permissive and does not halt informal urban expansion in areas of high environmental value.     

Agricultural land-use dynamics: Assessing the relative importance of socioeconomic and biophysical drivers for more targeted policy

A detailed understanding of multiple human and environmental factors influencing land allocations among agricultural uses can facilitate more efficient and targeted land policy. To show this, we used a comprehensive dataset of socioeconomic, physiographic, and climatic indicators to investigate potential determinants of land-use in Australia’s intensive agricultural region during the period 1992–2010. We applied a seemingly unrelated regressions land-use shares spatial error model with random effects coupled with variance decomposition analysis to identify the statistical significance, direction and magnitude of observed associations between land-use and its drivers.Population: density, rainfall, equity ratio, and access to markets were the most influential policy-relevant land-use factors. Land allocations to cereals and livestock production were significantly influenced by spatiotemporal rainfall and temperature variability. Improved pastures, cereals, annual and perennial crops plantations were larger in regions with better access to markets. Increases in equity ratio (i.e., better financial position) were associated with larger land allocations to improved pastures and annual crops and smaller extensive grazing area. Marginal associations were detected between land-use and output prices, and higher population density was associated with lower shares for all high value agricultural land-uses. The results suggest that improved transportation infrastructure, zoning regulations, and mechanisms to reduce farm debt exposure and risks from climate variability could have significant impact on the configuration of the Australian agricultural landscape.     

On the economics of forests and climate change: Deriving optimal policies

First-best optimal forest sector carbon policy is examined. Using a forest and energy sector model with a carbon cycle module we show that the renewability and carbon neutrality arguments do not warrant emission free status of wood use. As a general optimality principle, the release of carbon is penalized by a tax and carbon capture is subsidized. However, under the biomass stock change carbon accounting convention, the land owners pay for the roundwood emissions and, to avoid double counting, the use of roundwood is treated as emission free. Yet, the carbon accounting convention followed does not affect the equilibrium outcome. The bioenergy from harvest residues is not emission free either. Furthermore, we show that an optimal policy subsidizes the production of wood products for their carbon sequestration. Correspondingly, carbon removals by biomass growth are subsidized and the harvest residue generation taxed. Numerical solution of the model shows that, although the use of wood is not emission free, it is optimal to increase the use of wood, possibly also in the energy sector. Before the wood use can be increased, the forest biomass will be increased. This carbon sink decreases the net emissions until the forest resources reach a new equilibrium.     

Climate change: scenarios,impacts, policy,and development opportunities

This article is divided into three parts. First, it provides an overview of the main outcomes of the last IPCC assessment report, both in terms of economic drivers of greenhouse gas (GHG) emissions, and in terms of impacts of climate change, in particular for the agriculture sector. Then, it focuses on policy options and their optimal design, taking into account technological availability, international cooperation, and above all the stringency of the remaining carbon budget. Finally, it analyzes the size and direction of investment decisions required to stabilize GHG emissions and their implications for economic development.     

Urban sprawl and climate change: A statistical exploration of cause and effect,with policy options for the EU

This study provides a brief evaluation of the relationship between trends in transport emissions and urban land-use by analysing correlation between transport CO₂ emissions data, GDP and population data with land-use change data from the CORINE database for EU Member States between 1990 and 2000.     

Impacts of land-cover change on the water flow regulation ecosystem service: Invasive alien plants,fire and their policy implications

Land and water resource issues typically fall under separate governance systems. For example, agricultural policy regulates land-cover change while water departments regulate water quality. However, land-use changes can directly affect water resources. Water flow regulation is a key service which is affected by changes in land-cover but its dynamics are poorly understood by most policy makers and land management organisations. We simulated and quantified the effects of plant invasions on land-cover, hydrological soil characteristics and catchment responsiveness on flow regulation using a hydrological model. The case study was located in the indigenous fynbos shrublands in South Africa. Fynbos requires fire to regenerate, has moderate biomass, occurs mostly in areas with a potential to erode and is prone to invasion by woody plant species, particularly trees. Invasions can affect flow regulation by changing community structure and function and increasing fuel loads. The greater fuel load increases fire intensity and severity which, in turn, changes the hydrological responses of catchments. Few studies have assessed the effects of invasion on hydrological responses but studies on plantations have recorded significant increases in soil water repellence following fire, resulting in increased overland flow similar to impacts of fires in invaded areas. Simulation of clear-felling of pines and different degrees of water repellency increased both the responsiveness of the catchment to rainfall and extreme rainfall events. The simulated fire effects were consistent with other studies of hydrological responses to fire. Our study indicates that invasions of pines and acacias in the study area could substantially increase the risk of flood damage even from moderate rainfall events, and highlights the importance of maintaining flow regulation capacity. New policy approaches are required which take account of the linkages and interactions between land-use choices, water resources and ecosystem services, and address them when considering governance arrangements.     

Urban crops and livestock: The experiences,challenges, and opportunities of planning for urban agriculture in two Canadian provinces

While many municipalities globally are currently undertaking initiatives to support urban agriculture, policies and zoning regulations can act as barriers, with the former usually not integrated with planning. Extensive research has been conducted on urban agriculture policies in the global South, but much less is known about associated practices and policies in the global North. This is especially true for the Canadian context and therefore the present study aims at improving our overall understanding of the urban agriculture situation in two Canadian provinces. Relevant policies, such as official plans or official community plans, alternate policy documents and guidelines, zoning by-laws, and animal-related by-laws were reviewed for 10 municipalities in Ontario and in British Columbia, all varying in socio-economic and climatological characteristics. Additional key informant interviews were conducted with municipal planners, community garden coordinators, and other municipal staff familiar with urban agriculture policies from six of the selected municipalities.In line with global trends, our results suggest that urban agriculture is becoming more widespread in the two provinces. However, even though all studied municipalities consistently support urban agriculture, they vary significantly in their approach, with some municipalities focusing much more narrowly on certain types of activities than others. Overall, community advocacy and municipal council support are the most important drivers in the policy process. Key informants expressed a need to bridge existing gaps between policy adoption and implementation of tools, emphasize public education and public awareness, create inventories of land available for urban agriculture, incorporate urban agriculture in the development review process, and focus on the commercial potential of the practice. Encouragingly, despite the many challenges that need to be addressed, we found that many opportunities exist that municipalities could consider when creating improved local urban agriculture policies and tools to enhance the urban food system.