Showing papers on "Marginal land published in 2010"

Sustainability considerations for electricity generation from biomass

Abstract: The sustainability of electricity generation from biomass has been assessed in this work according to the key indicators of price, efficiency, greenhouse gas emissions, availability, limitations, land use, water use and social impacts. Biomass produced electricity generally provides favourable price, efficiency, emissions, availability and limitations but often has unfavorably high land and water usage as well as social impacts. The type and growing location of the biomass source are paramount to its sustainability. Hardy crops grown on unused or marginal land and waste products are more sustainable than dedicated energy crops grown on food producing land using high rates of fertilisers.

Energy Crops and Their Implications on Soil and Environment

Abstract: Interest in producing cellulosic ethanol from renewable energy sources is growing. Potential energy crops include row crops such as corn (Zea mays L.), perennial warm-season grasses (WSGs), and short-rotation woody crops (SRWCs). However, impacts of growing dedicated energy crops as biofuel on soil and environment have not been well documented. This article reviews the (i) impacts of growing WSGs and SRWCs on soil properties, soil organic carbon (SOC) sequestration, and water quality, and (ii) performance of energy crops in marginal lands. Literature shows that excessive (≥50%) crop residue removal adversely impacts soil and environmental quality as well as crop yields. Growing WSGs and SRWCs can be potential alternatives to crop residue removal as biofuel. Warm-season grasses and SRWCs can improve soil properties, reduce soil erosion, and sequester SOC. Crop residue removal reduces SOC concentration by 1 to 3 Mg ha -1 yr -1 in the top 10 cm, whereas growing WSGs and SRWCs increase SOC concentration while providing biofuel feedstocks. The WSGs can store SOC between 0 and 3 Mg C ha -1 yr -1 in the top 5 cm of soil, while the SRWCs can store between 0 and 1.6 Mg ha -1 yr -1 of SOC in the top 100 cm. The WSGs and SRWCs have more beneficial effects on soil and environment when grown in marginal lands than when grown in croplands or natural forests. Indeed, they can grow in nutrient-depleted, compacted, poorly drained, acid, and eroded soils. Development of sustainable systems of WSGs and SRWCs in marginal lands is a high priority.

A GIS-based approach to evaluate biomass potential from energy crops at regional scale

Abstract: The aim of the paper is to propose a method to maximize energy production from arboreous and herbaceous dedicated crops given the characteristics of the local environment: geo-morphology, climate, natural heritage, current land use. The best energy crops available in the Italian panorama are identified and the problem of maximizing the bioenergy production over an entire regional area is formulated. Each cultivar is thus assigned to the suitable land accounting for sensitive parameters that characterize it and taking into account current land use. The assumption made here is that marginal land and set-asides can be converted to energy crops without altering current practices and cash crops' production. The method is based on the integration of GIS data (spatially continuous) with data derived from the agricultural census (spatially discrete). We carry out the analysis for Emilia-Romagna, in Northern Italy. The sustainable growth of energy crops, with an optimized network of conversion facilities distributed in the territory, may significantly contribute to the local energy supply and to climate change mitigation.

Bird communities in future bioenergy landscapes of the Upper Midwest

Abstract: Mandates for biofuel and renewable electricity are creating incentives for biomass production in agricultural landscapes of the Upper Midwest. Different bioenergy crops are expected to vary in their effects on biodiversity and ecosystem services. Here, we use data from the North American Breeding Bird Survey to forecast the impact of potential bioenergy crops on avian species richness and the number of bird species of conservation concern in Midwestern landscapes. Our analysis suggests that expanded production of annual bioenergy crops (e.g., corn and soybeans) on marginal land will lead to declines in avian richness between 7% and 65% across 20% of the region, and will make managing at-risk species more challenging. In contrast, replacement of annual with diverse perennial bioenergy crops (e.g., mixed grasses and forbs) is expected to bring increases in avian richness between 12% and 207% across 20% of the region, and possibly aid the recovery of several species of conservation concern.

Soil organic carbon and nitrogen stocks in an age-sequence of poplar stands planted on marginal agricultural land in Northeast China

Abstract: Afforestation of marginal agricultural land has been considered to be an effective measure to sequester atmospheric CO2. In this study, we adopted the volume- and mass-based methods to investigate the changes in soil organic C and total N stocks in 100 cm depth following afforestation of marginal agricultural land using a chronosequence of poplar (Populus euramericana cv. “N3016”) stands in a semiarid region of Liaoning Province, Northeast China. Our results showed that soil organic C and total N concentrations in 45–60 cm layer increased gradually following afforestation of agricultural land, whereas in 60–100 cm layer, they declined initially, and then increased with stand development. Based on volume- and mass-based methods, such land-use change caused initial declines in soil organic C and total N stocks, and then increases between the stand ages of 10 and 20. Forest soils recovered to the initial soil organic C and N stocks found in agricultural land at age 15. However, the volume-based method would underestimate the absolute organic C and N stocks compared with the mass-based methods. Our results suggest that afforestation of marginal agricultural land has the potential to sequester atmospheric CO2 in soils in semiarid regions. Stand age, soil sampling depth and the methods used to quantify organic C and N stocks should be considered for accurate assessments of changes in soil organic C and N stocks.

Food security: increasing yield and improving resource use efficiency.

Abstract: Food production and security will be a major issue for supplying an increasing world population. The problem will almost certainly be exacerbated by climate change. There is a projected need to double food production by 2050. In recent times, the trend has been for incremental modest yield increases for most crops. There is an urgent need to develop integrated and sustainable approaches that will significantly increase both production per unit land area and the resource use efficiency of crops. This review considers some key processes involved in plant growth and development with some examples of ways in which molecular technology, plant breeding and genetics may increase the yield and resource use efficiency of wheat. The successful application of biotechnology to breeding is essential to provide the major increases in production required. However, each crop and each specific agricultural situation presents specific requirements and targets for optimisation. Some increases in production will come about as new varieties are developed which are able to produce satisfactory crops on marginal land presently not considered appropriate for arable crops. Other new varieties will be developed to increase both yield and resource use efficiency on the best land.

Marginal land-based biomass energy production in China.

Abstract: Fast economic development in China has resulted in a significant increase in energy demand. Coal accounts for 70% of China's primary energy consumption and its combustion has caused many environmental and health problems. Energy security and environmental protection requirements are the main drivers for renewable energy development in China. Small farmland and food security make bioenergy derived from corn or sugarcane unacceptable to China: the focus should be on generating bioenergy from ligno-cellulosic feedstock sources. As China cannot afford biomass energy production from its croplands, marginal lands may play an important role in biomass energy production. Although on a small scale, marginal land has already been used for various purposes. It is estimated that some 45 million hm2 of marginal land could be brought into high potential biomass energy production. For the success of such an initiative, it will likely be necessary to develop multipurpose plants. A case study, carried out on marginal land in Ningnan County, Sichuan Province with per capita cropland of 0.07 ha, indicated that some 380 000 tons of dry biomass could be produced each year from annual pruning of mulberry trees. This study supports the feasibility of producing large quantities of biomass from marginal land sources.

Invited Expert Review Marginal Land-based Biomass Energy Production in China

Abstract: Fast economic development in China has resulted in a significant increase in energy demand. Coal accounts for 70% of China's primary energy consumption and its combustion has caused many environmental and health problems. Energy security and environ- mental protection requirements are the main drivers for renewable energy development in China. Small farmland and food security make bioenergy derived from corn or sugarcane unacceptable to China: the focus should be on generating bioenergy from ligno- cellulosic feedstock sources. As China cannot afford biomass energy production from its croplands, marginal lands may play an important role in biomass energy production. Although on a small scale, marginal land has already been used for various purposes. It is estimated that some 45 million hm 2 of marginal land could be brought into high potential biomass energy production. For the success of such an initiative, it will likely be necessary to develop multipurpose plants. A case study, carried out on marginal land in Ningnan County, Sichuan Province with per capita cropland of 0.07 ha, indicated that some 380000 tons of dry biomass could be produced each year from annual pruning of mulberry trees. This study supports the feasibility of producing large quantities of biomass from marginal land sources.

Changes in Soil Particulate Organic Matter, Microbial Biomass, and Activity Following Afforestation of Marginal Agricultural Lands in a Semi-Arid Area of Northeast China

Abstract: Afforestation of agricultural lands has been one of the major land use changes in China in recent decades. To better understand the effect of such land use change on soil quality, we investigated selected soil physical, chemical and microbial properties (0–15 cm depth) in marginal agricultural land and a chronosequence of poplar (Populus euramericana cv. ‘N3016’) plantations (5-, 10-, 15- and 20-years old) in a semi-arid area of Northeast China. Soil bulk density significantly declined after conversion of agricultural lands to poplar plantations. Soil total organic carbon (TOC) and nitrogen (TN) concentrations, microbial biomass C (MBC) and potential N mineralization rate (PNM) decreased initially following afforestation of agricultural lands, and then increased with stand development. However, soil metabolic quotient (qCO2) exhibited a reverse trend. In addition, soil particulate organic matter C (POM-C) and N (POM-N) concentrations showed no significant changes in the first 10 years following afforestation, and then increased with stand age. These findings demonstrated that soil quality declined initially following afforestation of agricultural lands in semi-arid regions, and then recovered with stand development. Following 15 years of afforestation, many soil quality parameters recovered to the values found in agricultural land. We propose that change in soil quality with stand age should be considered in determining optimum rotation length of plantations and best management practices for afforestation programs.

Bacterial Communities in the Rhizosphere of Biofuel Crops Grown on Marginal Lands as Evaluated by 16S rRNA Gene Pyrosequences

Abstract: Microbes are key components of the soil environment and are important contributors to the sustainability of agricultural systems, which is especially significant for biofuel crops growing on marginal lands. We studied bacterial communities in the rhizosphere of five biofuel crops cultivated in four locations in Michigan to determine which factors were correlated to changes in the structure of those communities. Three of these sites were marginal lands in that two were not suitable for conventional agriculture and one was regulated as a brownfield due to prior industrial pollution. Bacterial community composition and structure were assessed by 454 sequencing of the 16S rRNA gene. A total of 387,111 sequences were used for multivariate statistical analysis and to test for correlation between community structure and environmental variables such as plant species, soil attributes, and location. The most abundant bacterial phyla found in the rhizosphere of all crops were Acidobacteria, Proteobacteria, Actinobacteria, and Verrucomicrobia. Bacterial communities grouped by location rather than by crop and their structures were correlated to soil attributes, principally pH, organic matter, and nutrients. The effect of plant species was low but significant, and interactions between locations, plant species, and soil attributes account for most of the explained variation in the structure of bacterial communities, showing a complex relationship between bacterial populations and their environment. Bacterial diversity was higher in the agricultural sites compared to adjacent forest sites, indicating that the cultivation of those biofuel crops increased the rRNA diversity.

Second Homes and Maximum Yield in Marginal Land The Re-Resourcing of Rural Land in Norway

Abstract: It is generally argued that commodification of rural areas leads to a change in the rural economy from being based on exploiting the physical environment to being mainly based on exploiting the aesthetical appeal of rural areas. In this article, however, it is revealed that commodification of rural areas in Norway is closely connected with exploitation of the physical environment, including through the re-resourcing of land from marginal agriculture and abandoned industrial sites into second home developments. This re-resourcing has also been an economic driving force for related tourist, housing and infrastructure developments. Politically, it has significantly influenced local power configurations. Simultaneously, external and local actors are commanded by stronger environmental regulations that govern the geography of re-resourcing. This article is based on studies of the municipalities of Ringebu and Kragero, Norway, using analysis of planning documents and qualitative interviews.

Sustainable Bioenergy Production, Land and Nitrogen Use

Abstract: In recent years the challenge of reducing the reliance on petroleum and natural gas with the energy produced by agricultural crops has received a renewed interest. However, many scientists have expressed serious reservations about the real benefit of a widespread diffusion of crops grown for energy feedstocks. While a diversification of energy portfolio is strongly needed, one of the greatest scientific challenge for the near future is to identify land use options that minimize negative impact on food prices and greenhouse gases emissions. The objective of this article is to discuss the following topics: (i) competition for land: bioenergy versus food; (ii) bioenergy crops and nitrogen cycling; (iii) plant traits to be targeted for improving land and nitrogen use efficiency; and (iv) the debated role of legumes. Because fertile land, suitable for food production, is a dwindling resource, the production of feedstocks for biofuels should be enhanced by exploiting favourable plant characteristics in marginal land areas. We point out that a rethinking of the concept of marginal land is necessary: not only areas poorly suited to grain crops production owing to low soil fertility, but also land unsuited to produce food owing to food safety reasons. Yet, whether a land area is marginal or not should be evaluated not only from the economic standpoint, but also from the ecological and environmental points of view. Moreover, grain crops residues should be exploited for bioenergy production providing that well devised height of cuttings assure the maintenance of soil organic matter. The main message of this review is that bioenergy should be seen as a complementary product of food and feed production, to be attained by optimized land and nitrogen use. Emphasis is given to the contribution that dedicated perennial lignocellulosic crops might provide in sustainable bioenergy production.

Agrarian adaptations in Tajikistan: land reform, water and law

Abstract: In Central Asia, agriculture and water management have ranked as the two most important economic activities in this arid environment. These activities gained even more prominence during the Soviet era as planners expanded irrigation into previously marginal land that bolstered their vision that the best land be allocated exclusively for cotton production. In the wake of the fall of the Soviet Union, Tajikistan has enacted laws meant to expand and clarify land use categories to meet the dual targets of expanding food production within the country while maintaining as much land as possible in cotton production – their economic mainstay. To this end, the Tajik government instituted five categories of land tenure. Though comprehensive, these new dispositions merely mask a continuation of top-down agrarian decision making implemented during the Soviet period. Consequently, this change has created new problems for farm labourers as they struggle to adapt to post-Soviet life and negotiate with the new bureaucrac...

Economic potential of agroforestry and forestry in the Lower Mississippi Alluvial Valley with incentive programs and carbon payments.

Abstract: Conversion of bottomland hardwood forests in the Lower Mississippi Alluvial Valley (LMAV) to agricultural land has caused a loss of ecosystem services. The primary approaches to reverse this have been the Wetlands Reserve Program and the Conservation Reserve Program, which provide financial incentives to landowners to reforest. However, other forest production regimes and forestry financing mechanisms will be necessary to meet reforestation goals. Using capital budgeting techniques, we estimated financial returns from eight agroforestry and seven forestry systems to compare to returns from agriculture on marginal and average lands in the LMAV, as an indicator for potential adoption. In all but a few cases, agriculture had higher returns than agroforestry and forestry, even on marginal lands, and this is especially true when considering federal agricultural payments. We then estimated the break-even carbon net revenue per metric ton that would create a large enough financial incentive to favor forestry or agroforestry systems over agriculture. Given prospective moderate prices from carbon credits from afforestation and reforestation activities and high costs for implementing those activities, a few forestry and agroforestry systems might have potential on marginal agricultural land in the LMAV, subject to requirements such as providing evidence that reforestation would not have taken place without carbon payments. Regimes that maintain a large carbon stock on site by avoiding clearcutting performed better under carbon markets.

Theory and Identification of Marginal Land and Factors Determining Land Use Change

Abstract: Biomass is being researched as a possible alternative to fossil sources of energy, in order to avoid externalities from fossil fuel use that affect the environment and the economy. Some biomass-based energy production systems may produce unwanted externalities in their own right, such as increasing the production pressure on the agricultural land base, resulting in a rise in prices of food commodities. Using marginal land for biomass production has been suggested as a solution. However, the definition of what constitutes marginal land is poorly understood. This paper provides a theoretical foundation for identification of marginal lands, and analyzes recent literature to assess how current usage of the term marginal correspond to the theoretical framework. Then, the paper devises empirical models that test possible methods of identification of the extensive margin of agricultural land in 19 counties in the state of Michigan. The models find that dynamic variables such as price changes have a statistically significant effect on land use change into and out of cropland. Land quality and regional effects are also statistically significant.

Conservation and Sustainable Management of Traditional Ecosystems in Garhwal Himalaya, India

Abstract: Forest and agricultural biodiversity play an important role in sustaining livelihood of local people in marginal land in Central Himalayan village ecosystems. These village communities have their own rules and regulations for conservation and management of agroecosystems as well as surrounding forest ecosystems. To assess the pattern of change in conservation and sustainable management of traditional agroecosystems, a participatory rural appraisal (PRA) was conducted and information collected from farmers. In the Study area traditional food crops and multipurpose agroforestry trees were replaced by cash crops during the recent past, due to the changes in the economic and political issues. These village ecosystems have become either degraded or less fertile ecosystems. The study focuses on the issues of conservation and sustainable development. (New York Science Journal. 2010;3(2):71-77). (ISSN: 1554-0200).

Livelihoods of Farming and Grazing Households and Land Use in Farming-Pastoral Transitional Zone:A Case Study of Uxin Banner in Ordos,Inner-Mongolia

Abstract: Based on the methods of questionnaire survey,semi-structured interview and mathematical statistics,153 farming and grazing households in Uxin Banner,situated in Ordos city,Inner-Mongolia,were inquired systematically,and then livelihood strategies,land use pattern of these households were explored.The results are presented as follows.1) Differences in livelihood strategies exist among distinctive types of households,and therefore income,the degree of living satisfaction,living pressures confronted and improving approaches vary accordingly.The households,engaging in just farming,encounter higher vulnerability and risk due to relatively simple livelihood strategies.Introduction and expansion of non-agricultural activities,and promoting livelihood diversity is a significant approach to reduce livelihood risk for these households.In contrast,households,living on both farming and grazing,confront lower risk as a result of higher and stable income.However,eco-environment is more vulnerable to their production activities.Therefore,developing economicefficiently and environmental-friendly agro-pastoral industry is the key to address livelihood issues of these households and to protect eco-environment.Furthermore,transferring rural people in grazing regions scientifically,reasonably and effectively is indispensible to mitigate pressure on pasture and to develop modern agro-pastoral industry.2) Fastening links exist between livelihood and land use types and intensity.Due to the inclination of labor force allocation to non-agricultural industries and the decrease in economic productivity of cropland,the households,engaging in just farming,invest less labors and capital,and so the land-use intensity become lower.In the pastoral area,the cultivated land derives from the reclamation of marginal land,and land users often adjust their investments according to the variations of net profits.When cropland falls into marginalization,grazing households will cease to cultivate.In addition,unreasonable grazing activities give rise to land degradation.

Shrub-based plantings of woody perennial vegetation in temperate Australian agricultural landscapes: What benefits for native biodiversity?

Abstract: Summary In the highly fragmented agricultural landscapes of temperate southern Australia, fodder shrubs are being established as part of commercial grazing enterprises to fill the summer-autumn livestock feed gap. These woody perennial plantings have greater structural complexity than conventional grazing systems and may supplement resources for native fauna. However, to date the resources provided by these systems are poorly defined or documented. In this paper, we identify the potential environmental values of fodder shrub plantings by considering natural and planted shrub-based systems, with a particular focus on planted saltbush in non-saline lands. In marginal agricultural areas, shrub-based perennial fodder crops can not only provide economic benefits through improved livestock productivity, but also contribute to reducing soil erosion and offer potential carbon sequestration opportunities. We contend that these systems may also provide resources for a range of native fauna. More information is needed on the biodiversity value of grazing systems based on perennial shrubs so that their potential to contribute to conservation in multifunctional landscapes can be fully realised and appropriate management recommendations provided.

Afforestation effect on soil quality of sand dunes.

Abstract: This study, undertaken in the Kapikoy sand dune area of the southern Mediterranean coast in Turkey, determined the changes in soil quality along with consequent economical revenue following 35 years of acacia, eucalyptus, and stone pine plantations on a 4,900 ha sand dune site. Significant soil phosphate (190 kg/ha) and organic matter (approx. 4%) accumulation were determined in the zones of vegetation when compared to bare sand dunes within 35 years. Moreover, the local people’s incomes from timber and stone pine nut production are increased, denoting a socio-economical improvement in the quality of life. Thus, the project appraised was successful not only for its positive effects on environmental parameters but also on socio-economic aspects. Lessons learned at Kapikoy set significant guidelines for recovering degraded marginal lands in the semi-arid Mediterranean coastal zone of Anatolia. Consequently, the outcomes of this study are expected to increase public awareness of the success of the aforestation projects with evident economic viability.

Marginal land, its boundaries, and the rupestral horoi of attica

Abstract: This study discusses whether the rupestral őϱol were in fact demarcating plots of marginal land otherwise known from the extant literary evidence, including the dominant Attic categories of σχατιά and φeλλeύς. The author argues that the development of marginal farming during the Classical and well into the Roman period induced entrepreneurs to claim ownership of productive lands in the hilly tracts of Attica. The rupestral őϱoι are best understood as reflections of this development, as markers of the economic landscape and as demarcations of the space from which members of corporate groups or individual farmers extracted a variety of different resources.

Marginal Land-based Biomass Energy Production in China

Abstract: 在中国的快经济开发导致了精力需求的重要增加。为 70% 中国的主要精力消费和它的燃烧的煤报道引起了环境的许多和健康问题。精力安全和环境保护要求是为在中国的可更新的精力开发的主要司机。小农田和食物安全使 bioenergy 从玉米或对中国不能接受的甘蔗导出：焦点应该在从 ligno 有纤维质的化工物品来源产生 bioenergy 上。当中国不能从它的农田负担得起生物资源精力生产，边缘的陆地可以在生物资源精力生产起一个重要作用。尽管在小规模上，边缘的土地已经被用于各种各样的目的。边缘的土地的大约 4500 万 hm2 能被带进高潜在的生物资源精力生产，这被估计。为如此的一个行动的成功，开发多种用途的植物将多半是必要的。案例研究，在 Ningnan 县在边缘的土地上执行了，有 007 的人均的农田的四川省哈，显示大约 380 000 个大量干燥生物资源每年能从桑树树的年度修剪被生产。这研究支持从边缘的陆地来源生产生物资源的大数量的可行性。

Would There Be Surplus Grains for Biofuels? An Assessment of Agro-economic Factors and Biofuel Production Potential at the Global Level

Abstract: We assessed agricultural land’s potential as to food supply and biofuel production. Agricultural land use has been steadily increasing worldwide as one means of feeding the burgeoning global population. If this same land, currently in agricultural production for food purposes, is diverted for biofuel production then it is most probably going to have an impact on global food supply. In this study, we first assessed the characteristics of land and where crops can be successfully grown based on the qualifications of weather, land intensification, land quality, and cropping patterns. Use of land in biofuel production, under current existing technologies, would need a significant expansion of agricultural land in both developed and developing countries from their current levels. We assessed the supply potential of the World Bank’s 25 classified regions for biofuel and also for meeting food production needs under the whole grain production, current per capita consumption, and optimal grain consumption based on vegetarian, normal and affluent diets under a variety of scenarios that encompass both increases in productivity and increases in pasture land conversion to grain crop cultivation. Results indicate that under the whole grain need criterion, the world will have a surplus balance of grains by 2050 (even if production is increased at only the 40% level). When requirements for a vegetarian diet are assumed, a productivity increase of 60% at current land levels would be required to meet global grain needs. When a moderate diet requirement assumption is made, expansion of crop production in existing pasture and meadow land would be necessary to meet food demand. An affluent diet requirement would require a fairly substantial increase in productivity and expansion of crop production to marginal land in order to meet world food demand by 2050. Plantings of switchgrass and Miscanthus on marginal lands can produce much more biofuel than needed but stress on land resources, water quality, water quantity, and the need for a huge amount of production inputs may create a hindrance for its implementation in the future. Additionally, it will require advances in cost effective technology that will then be capable of producing biofuel from lignocellulosic feedstocks. Minimally, to meet moderate diet requirements in 2050, there will be need to expand grain crops in 30% pasture land and to meet at least 10% average world biofuel mandated need additional 3.3% pasture land needs to be planted with lignocellulosic crops such as switchgrass.

A Real Options Method for Estimating the Adoption Potential of Forestry and Agroforestry Systems on Private Lands in the Lower Mississippi Alluvial Valley, USA

Abstract: The Lower Mississippi River Alluvial Valley (LMAV), once was the largest forested bottomland area in the continental United States, but has undergone widespread loss of forest through conversion to farmland. Restoration of forest functions and values has been a key con servation goal in the LMAV since the 1970s. This study utilizes a partial differential real options method to determine the optimal switching price and return thresholds between agriculture and forestry and agriculture and agroforestry systems for specific marginal land types in the LMAV. A good land manager will value practices that give him/her the option to change or postpone decisions in order to adapt to changing conditions. Real options techniques value flexibility under variable conditions, known as option value, whereas traditional cost-benefit methods (NPV, SEV, etc.) assume deterministic returns and that farmers’ decisions will not change in the future. Loss of option value incurred by switching from agriculture to forestry or agroforestry may partially explain adoption rates that are lower than predicted by cost -benefit methods. The price conditions under which farmers are likely to adopt forestry/agroforestry are calculated and compared to empirical evidence from government forestry incentive programs. Agroforestry and forestry systems were shown have potential for adoption on the most marginal lands in the LMAV, but are not likely to be adopted on soils of average productivity. Easement payments or incentive payment programs such as payments for ecosystem services would be needed to encourage adoption.

Indiscriminate devegetation under improper farming system: a root cause for surface and underground water and food crisis in Ethiopia

Abstract: Deforestation has caused surface and underground water imbalance in the hydrologic cycle followed by subsequent food, feed and wood productivity crisis. This paper reviews the role of traditional farming systems in wet and dry agroecology. It further compares it with existing improper farming practice, which productivity is examined from agroecology based climatic and edaphic perspective. Experiments were carried out to determine the amount of rainfall intercepted by dominant trees on farm, namely by Cordia africana, Afrocarpus falcatus, Millettia ferruginea, Jimiperus procera, Syzygium guineense, Olea europaea subsp. cuspidata, Acacia albida, Albizia gummifera and Moringa stenopetala. Deep rooted trees planted on farms are found to be sources of feed, food and moisture conservers, that sustain and boost production in moisture scarce agriculture. Under irrigation they are found to be good for salinity protection and marginal land reclamation. Soil infiltration data from secondary sources were examined for cultivated area, wood land and open overgrazed pasture in central Rift Valley. The relative infiltration rates are highest for grasslands. This research work is intended to initiate interdisciplinary networking approach in water and natural resource conservation, proper land use potential development and environmental sustainability.

Impact of Large-Scale Biofuels Production on Cropland-Pasture and Idle Lands

Abstract: An important criticism of the indirect land use change (ILUC) estimates of biofuels to date is that they have not accounted for the presence of marginal lands such as cropland-pasture and idle-lands. This paper offers a novel framework for analyzing the impact of biofuels production on these marginal lands. The methodology includes the steps involved in identifying and incorporating marginal land data such as area under cropland-pasture and idle lands such as U.S. Federal Conservation Reserve Program (CRP) enrolled land into the database, computing the associated land-rents which imply productivity of land, and specifying the marginal lands in the land supply function in a computable general equilibrium model. Two policy scenarios are examined in this study: 1) implementing U.S. and EU biofuel mandates for 2015 and 2) implementing the corn-ethanol only mandate by 2015 in the U.S. These policy experiments also look at the potential implications of releasing or fixing the CRP land enrollment by the USDA on global land-use and land-cover changes. The results revealed that though accessibility of these marginal lands dampens large shifts in cropping patterns, the ILUC emissions measured in terms of grams of CO¬2 equivalent per MJ of biofuel produced, were significantly affected mainly due to increase in deforestation when the cropland-pasture is used for cultivation of crops. Future research to more accurately characterize the productivity of these marginal lands will be needed. JEL Classification: C68, Q18, Q23, Q24, Q42, R14 Keywords: Biofuels, computable general equilibrium (CGE), Agro Ecological Zones (AEZs), land use change, marginal lands, idle lands, cropland-pasture, conservation reserve program (CRP).