Pecologix Political Ecology Blotter » policy (f)

Additional CO2 emissions from land use change — Forest conservation as a precondition for sustainable production of second generation bioenergy

A. Cherson — Mon, 30 Jan 2012 02:53:56 +0000

In the past, deforestation, mainly driven by the conversion of natural forests to agricultural land, contributed up to one-fifth of global human induced carbon dioxide (CO₂) emissions. Substitution of bioenergy for fossil energy is an intensely discussed option for mitigating CO₂ emissions. This paper, by applying a global land-use model and a global energy–economy–climate model, explores how demand for cellulosic bioenergy crops will add an additional pressure on the land system in the future. In accordance with other studies, we find that CO₂ emissions from land use change due to energy crop production will be an important factor in the GHG balance of bioenergy if natural forests will not be protected. But restricting land availability for biomass plantations by conserving natural forests requires additional efforts in the agricultural sector: First, our simulation results indicate that significant additional crop yield increases will be needed due to the combination of forest conservation and the cultivation of dedicated bioenergy crops. Secondly, our simulation results show that forest conservation in combination with increasing demand for dedicated bioenergy crops will lead to higher agricultural production costs of approximately 20%.

DOI: http://dx.doi.org/10.1016/j.ecolecon.2011.11.004

Push-pull technology: a conservation agriculture approach for integrated management of insect pests, weeds and soil health in Africa

A. Cherson — Thu, 10 Nov 2011 13:06:37 +0000

Push-pull technology (www.push-pull.net) is based on a novel cropping system developed by the International Centre of Insect Physiology and Ecology, Rothamsted Research (UK) and national partners for integrated pest, weed and soil management in cereal-livestock farming systems. Stemborers are attracted to Napier grass (Pennisetum purpureum), a trap plant (pull), and are repelled from the main cereal crop using a repellent legume intercrop (push), desmodium (Desmodium spp.). Desmodium root exudates effectively control the parasitic striga weed by causing abortive germination. Desmodium also improves soil fertility through nitrogen fixation, natural mulching, improved biomass and control of erosion. Both companion plants provide high value animal fodder, facilitating milk production and diversifying farmers’ income sources. The technology is appropriate to smallholder mixed cropping systems in Africa. It effectively addresses major production constraints, increases maize yields from below 1 to 3.5t/ha, and is economical as it is based on locally available plants, not expensive external inputs. Adopted by over 30,000 farmers to date in East Africa, key factors in its further up-scaling include effective technology dissemination, adaptability of companion plants for climate resilience, capacity building and multi-stakeholder collaboration, integration with livestock husbandry, improvement in input accessibility and creation of a supportive policy framework.

DOI: http://dx.doi.org/10.3763/ijas.2010.0558

Dial “A” for agriculture: a review of information and communication technologies for agricultural extension in developing countries

A. Cherson — Mon, 20 Jun 2011 18:21:45 +0000

Agriculture can serve as an important engine for economic growth in developing countries, yet yields in these countries have lagged far behind those in developed countries for decades. One potential mechanism for increasing yields is the use of improved agricultural technologies, such as fertilizers, seeds, and cropping techniques. Public sector programs have attempted to overcome information-related barriers to technological adoption by providing agricultural extension services. While such programs have been widely criticized for their limited scale, sustainability, and impact, the rapid spread of mobile phone coverage in developing countries provides a unique opportunity to facilitate technological adoption via information and communication technology (ICT)-based extension programs. This article outlines the potential mechanisms through which ICT could facilitate agricultural adoption and the provision of extension services in developing countries. It then reviews existing programs using ICT for agriculture, categorized by the mechanism (voice, text, internet, and mobile money transfers) and the type of services provided. Finally, we identify potential constraints to such programs in terms of design and implementation, and conclude with some recommendations for implementing field-based research on the impact of these programs on farmers’ knowledge, technological adoption, and welfare.

DOI: http://dx.doi.org/10.1111/j.1574-0862.2011.00545.x

Benchmark map of forest carbon stocks in tropical regions across three continents

A. Cherson — Thu, 16 Jun 2011 14:26:41 +0000

Developing countries are required to produce robust estimates of forest carbon stocks for successful implementation of climate change mitigation policies related to reducing emissions from deforestation and degradation (REDD). Here we present a “benchmark” map of biomass carbon stocks over 2.5 billion ha of forests on three continents, encompassing all tropical forests, for the early 2000s, which will be invaluable for REDD assessments at both project and national scales. We mapped the total carbon stock in live biomass (above- and belowground), using a combination of data from 4,079 in situ inventory plots and satellite light detection and ranging (Lidar) samples of forest structure to estimate carbon storage, plus optical and microwave imagery (1-km resolution) to extrapolate over the landscape. The total biomass carbon stock of forests in the study region is estimated to be 247 Gt C, with 193 Gt C stored aboveground and 54 Gt C stored belowground in roots. Forests in Latin America, sub-Saharan Africa, and Southeast Asia accounted for 49%, 25%, and 26% of the total stock, respectively. By analyzing the errors propagated through the estimation process, uncertainty at the pixel level (100 ha) ranged from ±6% to ±53%, but was constrained at the typical project (10,000 ha) and national (>1,000,000 ha) scales at ca. ±5% and ca. ±1%, respectively. The benchmark map illustrates regional patterns and provides methodologically comparable estimates of carbon stocks for 75 developing countries where previous assessments were either poor or incomplete.

doi: http://dx.doi.org/10.1073/pnas.1019576108

Recent rates of forest harvest and conversion in North America

A. Cherson — Thu, 28 Apr 2011 22:55:15 +0000

This paper summarizes recent (2000–2008) rates of extraction, including both conversion and harvest, derived from national forest inventories for North America (the United States, Canada, and Mexico). During the 2000s, 6.1 million ha/yr were affected by harvest, another 1.0 million ha/yr were converted to other land uses through gross deforestation, and 0.4 million ha/yr were degraded. Thus about 1.0% of North America’s forests experienced some form of anthropogenic disturbance each year. However, due to harvest recovery, afforestation, and reforestation, the total forest area on the continent has been roughly stable during the decade. On average, about 110 m3 of roundwood volume was extracted per hectare harvested across the continent. Patterns of extraction vary among the three countries, with U.S. and Canadian activity dominated by partial and clear-cut harvest, respectively, and activity in Mexico dominated by conversion (deforestation) for agriculture. Temporal trends in harvest and clearing may be affected by economic variables, technology, and forest policy decisions. While overall rates of extraction appear fairly stable in all three countries since the 1980s, harvest within the United States has shifted toward the southern United States and away from the Pacific Northwest.

doi: http://dx.doi.org/10.1029/2010JG001471

Cash alone from REDD will not slow forest carbon emissions

A. Cherson — Sat, 19 Mar 2011 14:48:07 +0000

These data reveal the central role of government choice. Studies compiled by the Rights and Resources Initiative (RRI) in Washington DC show that governments, not local people, are the primary drivers of global deforestation. Government policy and investment, generally encouraged by global demand for food, energy and wood fibre, sets off a chain reaction that leads to forest degradation or destruction. This is no surprise, given that governments still claim ownership over some 70% of tropical forests globally.If government policy is behind the majority of deforestation, it is hard to see how cash payments through REDD would bring change. In Indonesia, the government-sponsored palm-oil industry generated more than $12 billion in government revenues alone in 2010 — much more than the $1 billion offered by Norway to establish REDD. Even if the carbon market works, REDD cannot compete.The focus of REDD on finance has blinded us to other approaches to reducing forest emissions. Research shows that where indigenous peoples and forest communities have their rights recognized, they are far better forest stewards than are governments. A study by the RRI, commissioned by the World Bank, shows that the cost per hectare of recognizing rights is orders of magnitude less than the estimated costs of REDD. South Korea, China, Vietnam and Nepal have increased their forests in recent years, and an RRI study of global forest restoration shows that they have three things in common: sustained political commitment to reforestation, reforms to support local property rights and forest management, and local economic development.

doi: http://dx.doi.org/10.1038/471267a