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Biogeochemical Factors Contributing to Enhanced Carbon Storage Following Afforestation of a Semi-Arid Shrubland
(2007) Grunzweig, J. M.; Gelfand, I.; Yakir, D.
"Ecosystems in dry regions are generally low in productivity and carbon (C) storage. We report, however, large increases in C sequestration following afforestation of a semi-arid shrubland with Pinus halepensis trees. Using C and nitrogen (N) inventories, based in part on site-specific allometric equations, we measured an increase in the −2 −2 standing ecosystem C stock from 2380 g C m in the shrubland to 5840 g C m in the forest after 35 years, with no significant change in N stocks. The total amount of C produced by the forest was estimated as 6250 g Cm. Carbon sequestration following afforestation was associated with increased N use efficiency as reflected by an overall increase in C/N ratio from 7.6 in the shrubland to 16.6 in the forest. The C accumulation−2 rate in the forest was particularly high for soil organic C (SOC; increase of 1760 g C m −2 −1 or 50 g C m yr ), which was associated with the following factors: 1) Analysis of a 13 small C signal within this pure C3 system combined with size fractionation of soil organic matter indicated a significant addition of new SOC derived from forest vegetation (68% of total forest SOC) and a considerable portion of the old original shrubland SOC (53%) still remaining in the forest. 2) A large part of both new and old SOC appeared to be protected from decomposition as about 60% of SOC under both land-use types were in mineral-associated fractions. 3) A short-term decomposition study indicated decreased decomposition of lower-quality litter and SOC in the forest, based on reduced decay rates of up to 90% for forest compared to shrubland litter. 4) Forest soil included a significant component of live and dead roots. Our results showed the considerable potential for C sequestration, particularly in soils, following afforestation in semi-arid regions, which is particularly relevant in light of persistent predictions of drying trends in the Mediterranean and other regions."
Carbon, Land and Water: A Global Analysis of the Hydrologic Dimensions of Climate Change Mitigation through Afforestation/Reforestation
(2006) Zomer, Robert J.; Trabucco, Antonio; van Straaten, Oliver; Bossio, Deborah
"Climate change and global warming have become familiar notions throughout the world, as the profound impact that human activities have made on global biogeochemical cycles is increasingly recognized. The global carbon cycle has received much international attention as it has become increasingly obvious that increased levels of CO2 in the atmosphere are causing changes in our climate at an alarming rate. The Kyoto Protocol is an international effort aimed at mitigating climate change through the reduction of greenhouse gas emissions into the atmosphere. Within the Kyoto Protocol, the Clean Development Mechanism (CDM) is an instrument which is intended to reduce greenhouse gas emissions, while assisting developing countries in achieving sustainable development, with the multiple goals of poverty reduction, environmental benefits and costeffective emission reductions. The CDM allows for a small percentage of emission reduction credits to come from reforestation and afforestation (CDM-AR) projects. "In this report, we articulate the hidden water dimensions of international efforts to mitigate climate change through multilateral treaties through a global analysis of land suitability and water use impacts of CDM-AR carbon sink projects. Large amounts of land were identified globally as biophysically suitable and meeting the CDM-AR eligibility criteria. The eco-sociologic characteristics of these suitable areas were examined, with results showing that much of this land is under rain-fed and/or subsistence agriculture or savannah land. Large amounts of suitable land exhibited relatively low population densities. Generally, most of this land is below 1,000 meters (m) in elevation and of moderate productivity. "If converted to forest, large areas deemed suitable for CDM-AR would exhibit increases in actual evapotranspiration and/or decreases in runoff, i.e., a decrease in water potentially available off-site for other uses. This is particularly evident in drier areas, the semi-arid tropics, and in conversion from grasslands and subsistence agriculture. However, major direct impacts of CDM-AR at the global and regional scales on water resources and food security are ascertained as unlikely, primarily due to the UNFCCC mandated cap on CDM-AR at one percent per annum of total emission obligations. However, significant changes in CDM-AR rules affecting the number of projects or amount of land that could eventually be under CDM-AR, should take into account these potential impacts on the hydrological cycle, and related food security issues. At the local and project level scale, impacts on water use was substantial. It was evident that CDM-AR projects can benefit from identifying locally optimal locations for tree plantations that maximize the positive aspects of increased green water vapor flows and reduced runoff. "This report highlights the potentially significant impacts on the hydrologic cycle and the importance of considering secondary effects, particularly with regard to water, resulting from the widespread adoption of global climate change mitigation measures. It is recommended that the implicit hydrologic dimensions of climate change mitigation should be more formally articulated within the international environmental conventions, and recognized within future UNFCCC negotiations on the CDM-AR provisions."
Combined Biogeophysical and Biogeochemical Effects of Large-Scale Forest Cover Changes in the MPI Earth System Model
(2010) Bathiany, S.; Claussen, M.; Brovkin, V.; Raddatz, T.; Gayler, V.
"Afforestation and reforestation have become popular instruments of climate mitigation policy, as forests are known to store large quantities of carbon. However, they also modify the fluxes of energy, water and momentum at the land surface. Previous studies have shown that these biogeophysical effects can counteract the carbon drawdown and, in boreal latitudes, even overcompensate it due to large albedo differences between forest canopy and snow. This study investigates the role forest cover plays for global climate by conducting deforestation and afforestation experiments with the earth system model of the Max Planck Institute for Meteorology (MPI-ESM). Complete deforestation of the tropics (18.75 S–15 N) exerts a global warming of 0.4 C due to an increase in CO2 concentration by initially 60 ppm and a decrease in evapotranspiration in the deforested areas."
Cooperation in Forestry between the Northern and Southern Mediterranean
(1999) Malagnoux, Michele; Lanly, Jean-Paul
"A clear distinction exists between the forest situation in northern Mediterranean and that found in southern Mediterranean countries. Urbanization and a decline in farming in northern Mediterranean countries has left the countryside in an abandoned state, more or less unmanaged by landowners who tend to be unaware of good land management practices. Combustible woody materials are left to accumulate, which combine with the region's dry summer weather and strong winds to heighten the risk of fire."
An Evaluation of Farmers’ Participation in Afforestation Programme in Kogi State, Nigeria
(2010) Saliu, O.J.; Alao, J.S.; Oluwagbemi, T.
"Extensive deforestation has reduced the 65 million hectares of intact forest cover of 1897 in Nigeria to the present 4 million hectares. The consequences of this unhealthy development have resulted to environmental degradation and accelerated wind and water erosion of the fertile land that has also left Nigerian soil too poor for sustainable agricultural production. Reforestation through small-scale village based farmers’ participation now form one of the strategies embarked upon by several agencies in Nigeria including Kogi afforestation project. This study attempts to evaluate farmers’ participation in afforestation project in Kogi State. Structured questionnaire was used to interview 120 participants. Descriptive statistics, adoption index and sigma method were used to describe socio-economic characteristics, participation methods and to measure the level of adoption while chi-square was used to find differences between income generated from adoption of the various afforestation technologies. Findings reveal that 67 percent of the farmers had little or no formal education, more than 30 percent of the farmers underwent passive participation in afforestation while adoption of improved seedlings, exotic trees and pure stand technologies received high score of 4.90, 4.74 and 4.44 respectively. Seed scarification and harvesting by chipping technologies received the least adoption score of 2.61 and 2.94. The chi-square test adjudged that there was a significant difference between income generated and type of technology adopted. This study recommends that more pragmatic interactive participation method that will give room for joint analysis of action plan and formation of local institutions should be put in place."
Forest Carbon and Local Livelihoods: Assessment of Opportunities and Policy Recommendations
(2002) Smith, Joyotee; Scherr, Sara J.
"Projects implemented as part of the Clean Development Mechanism (CDM) of the Kyoto Protocol will have the dual mandate of mitigating greenhouse gas emissions and contributing to sustainable development. Basic agreement on core elements was reached in 2001, including the decision to allow afforestation and reforestation projects. However, it is not yet clear what rules will address social concerns. Many types of projects could potentially contribute to local livelihoods and ecosystem restoration, as well as to carbon emission offsets, including those using natural forest regeneration, agroforests, improved forest fallows, and agroforestry."
Geospatial Information Technology for Conservation of Coastal Forest and Mangroves Environment in Malaysia
(2008) Jusoff, Kamaruzaman
"Mangrove forests are one of the most productive and bio-diverse wetlands environments on earth. Yet, these unique coastal tropical forests environment are among the most threatened habitats in the world. Growing in the intertidal areas and estuary mouths between land and sea, mangroves provide critical habitat for a diverse marine and terrestrial flora and fauna. The important need of living being is opportunity to continue their life in sustainable environment and suitable conditions. Potential stand is the place that obtains the possibility of germination and establishment of a plant species according to their physical, chemical, biological demands. In many cases are seen that because of unsuitable selection of site and species, afforestation and reforestation projects after spending time, cost and labor are forced to failure. Therefore, it is an obligation by the relevant authorities, especially Forestry Department to ensure that the rate of seedlings survival in the afforestation and reforestation activities is successfully monitored, mapped and quantified. One of the most efficient techniques available is the use of Geospatial Information Technology consisting of Geographical Information Systems (GIS), Global Positioning System (GPS) and remote sensing (RS). Using this technology and integrating the different thematically maps that shows environmental conditions of specific region, suitable and potential positioning of different species for plantation and rehabilitation programs could be well determined and monitored. For mapping and detection of individual mangrove species for reforestation and afforestation purposes, mathematical functions such as Boolean logic, fuzzy logic, and neural network can be easily applied. It is expected that suitable species-site matching for reforestation and afforestation of mangroves could be implemented with such geospatial tools."
Greening the 'Wastelands': Evolving Discourse on Wastelands and its Impact on Community Rights in India
(2011) Saigal, Sushil
"This paper explores the evolution of 'wastelands' discourse in India – from the colonial time to the present – and how it has shaped India’s land and forest policies, and though them community rights on these two vital natural resources. The concept of wastelands originated in India during the colonial period. All lands that were not under cultivation (revenue-yielding lands) were classified as wastelands and the state asserted its proprietary rights over them. Some of these were later reclassified as forests or allotted for cultivation and plantation. Thus, the idea of wastelands originated from the perspective of revenue rather than ecology. After independence, the discourse surrounding wastelands changed. The national government was less interested in land revenue but was keen on expanding agriculture to make the country self-sufficient in food. During this period, wastelands came to be viewed as empty lands available for expanding agriculture and settling agricultural labourers. With the country achieving food self-sufficiency in the 1970s, the discourse surrounding wastelands changed again. Now degradation of forests and shortages of fuelwood and fodder were seen as the main challenges. A massive afforestation programme was launched in the 1980s to bring 33% of the country under tree cover. Subsequently, the emphasis shifted more towards the watershed role of wastelands and a watershed development programme was launched for soil and moisture conservation. More recently, the wastelands discourse has moved towards addressing the challenges posed by climate change. This changing national discourse on wastelands has profoundly impacted India’s land and forest policies, and through them livelihoods of many people, especially rural communities. An awareness of this continually evolving discourse helps in better understanding of various land- and forest-related programmes and projects and their outcomes."
Incorporating Changes in Albedo in Estimating the Climate Mitigation Benefits of Land Use Change Projects
(2008) Bird, D. N.; Kunda, M.; Mayer, A.; Schlamadinger, B.; Canella, L.; Johnston, M.
"Some climate scientists are questioning whether the practice of converting of non-forest lands to forest land (afforestation or reforestation) is an effective climate change mitigation option. The discussion focuses particularly on areas where the new forest is primarily coniferous and there is significant amount of snow since the increased climate forcing due to the change in albedo may counteract the decreased climate forcing due to carbon dioxide removal. In this paper, we develop a stand-based model that combines changes in surface albedo, solar radiation, latitude, cloud cover and carbon sequestration. As well, we develop a procedure to convert carbon stock changes to equivalent climatic forcing or climatic forcing to equivalent carbon stock changes. Using the model, we investigate the sensitivity of combined affects of changes in surface albedo and carbon stock changes to model parameters. The model is sensitive to amount of cloud, atmospheric absorption, timing of canopy closure, carbon sequestration rate among other factors. The sensitivity of the model is investigated at one Canadian site, and then the model is tested at numerous sites across Canada. In general, we find that the change in albedo reduces the carbon sequestration benefits by approximately 30% over 100 years, but this is not drastic enough to suggest that one should not use afforestation or reforestation as a climate change mitigation option. This occurs because the forests grow in places where there is significant amount of cloud in winter. As well, variations in sequestration rate seem to be counterbalanced by the amount and timing of canopy closure. We close by speculating that the effects of albedo may also be significant in locations at lower latitudes, where there are less clouds, and where there are extended dry seasons. These conditions make grasses light coloured and when irrigated crops, dark forests or other vegetation such as biofuels replace the grasses, the change in carbon stocks may not compensate for the darkening of the surface."
Land-Use Effects on Flood Generation: Considering Soil Hydraulic Measurements in Modelling
(2009) Wahren, A.; Feger, K. H.; Schwarzel, K.; Munch, A.
"The investigation in the catchment of the Mulde (51◦ 0 55 N, 13◦ 15 54 E Saxony, Germany) researches the effect of afforestation measures on the soil hydraulic properties. The concept of a 'false chronosequence' was used to quantify the time-dependent dynamical character of the forest impact. Four adjacent plots were identified at a test location with comparable pedological start conditions and a set of tree stands of different age: (1) arable field (initial state); (2) 6-year-old afforestation; (3) 50-year-old afforestation; (4) ancient natural forest (“target” stocking). Water retention curves and unsaturated conductivities were analysed in the lab. In the field, the undisturbed infiltration capacities were measured quantitatively (hood infiltrometer) and qualitatively (brilliant blue tracer). Pronounced differences between all 4 plots were detected. The afforestation causes an increased infiltration and soil water retention potential. Especially the topsoil layers showed a distinct increase in conductivity and portion of coarse/middle pores. The influence of these changes on rainfall-runoff calculations at the test location was analysed in this study."
Landscapes as Commons: Afforestation and the aesthetics of Landscapes
(2008) Ritter, E.
"Afforestation can change a landscape distinctively, partly due to the choice of tree species, partly due to the design of forest stands. Visible changes in a landscape can have a strong emotional effect on people as the main part of our perception of landscape occurs through the sense of sight. Furthermore, the contact to nature can be considered as a basic need of human beings. Landscapes and the aesthetics of landscapes should therefore be considered as valuable commons, and forest managers and landscape designers should be aware of their influence. In this paper, afforestation is used as an example for cross-scale interactions of different interests, because afforestation activities in most countries are driven by many other than scenic aspects. An Icelandic study shows how interests of forestry and land reclamation could be combined with the interests of people in the beauty of the landscape. Due to radical deforestation in the first centuries of the settlement, Iceland has lost most of its forests, and people are generally used to the open landscape. For this reason, it is important to act sensitively when establishing the new forests that are highly needed in order to fight the ongoing soil erosion. Especially the exotic evergreen trees used in Icelandic afforestation programmes change the appearance of the Icelandic landscape. They catch the viewer's eye in winter time when the landscape is mostly brown during the absence of snow cover. A study on soil properties did not reveal major effects of tree species. Therefore, it is suggested that forest managers could neglect the effects on soil properties and base their decisions about the choice of trees species primarily on people's preferences."
Linking Reforestation with Forest Policies: A Multi-Scale and Interdisciplinary Methodology Applied to Vietnam
(2008) Clement, Floriane; Amezaga, Jaime M.; Orange, Didier; Calder, Ian R.; Large, A. R. G.
"A large number of countries have initiated similar sets of policies aiming to increase forest cover. These have usually included large- scale afforestation campaigns and the devolution of land property rights to households. Most of the research works that have analysed the link between state policies and land-use change have hitherto been restricted either to qualitative local level studies or to quantitative macro-scale analyses. The former have offered an in-depth understanding of the drivers for farmers decisions but their applicability to different local contexts is questionable. The latter have identified general trends and proximate causes for reforestation but often without being able to explicitly separate the effect of a particular policy or to ascertain the causal mechanisms that link policy and land-use change. Using the Institutional Analysis and Development (IAD) framework as a unifying canvass, our assessment of the impact of forest policies on reforestation in Vietnam investigates several governance levels and uses both quantitative and qualitative approaches. We started from the analysis of farmers land use decisions at the local level relying on ethnographical methods and institutional analysis. Then, we used these findings to build models of forest cover change, which were tested at the meso-scale level using remotely-sensed data and spatial regression analysis. This quantitative study was complemented by an institutional and political economy approach that explored the underlying drivers for reforestation and policy implementation at the provincial level. Finally, a discursive and political ecology perspective allowed us to analyse the role of the prevailing narratives and beliefs in policy design at the national level. We discuss in this paper why this multi-level and holistic methodology is particularly effective for identifying the links between policies and forest cover change and for understanding the discrepancies that exist between policy intentions and observed outcomes. Lastly, we argue that this approach is also particularly well suited for designing and effectively disseminating appropriate policy recommendations."
Logiques Paysannes et Reboisement: Le Cas d'Andohavary sur les Hautes Terres de Madagascar
(1997) Pleines, Thierry; Schmithusen, Franz; Song, Jean-Pierre
"The small farmers perception of a development initiative, as determined by their cultural, socioeconomic and ecological circumstances, differs from that of the technocrats. This article demonstrates that it is possible to crystallize, on the basis of semi-structured interviews, the rationale of the villagers and that this type of research enables development workers to attain a greater understanding of the farmer. The data was collected in a village not far from the Madagascan capital. It indicates that participation in reforestation was primarily motivated by the desire to assume land ownership and the production of wood. The farmers consider the planting of trees as a long term initiative, with a view to self sufficiency. They perceive the tree planting to be an inherent part of social and rural life."
Planting Power: The Afforestation of the Commons and State Formation in Portugal
(1995) Brouwer, Roland
"This book discusses the afforestation of the commons in Portugal by the state Forestry Service. It shows that tree planting was part of the subjection of the local population to state law and power."
The Role of Trees for Sustainable Management of Less-Favored Lands: The Case of Eucalyptus in Ethiopia
(2000) Jagger, Pamela; Pender, John
"In recent years the planting of eucalyptus trees in Ethiopia has expanded from State owned plantations to community woodlots and household compounds. In an environment suffering from severe woody biomass shortages water scarcity, erosion and land degradation, fast growing and resilient eucalyptus species perform better than most indigenous woodland and forest tree species (as well as most crops). In addition to increasing biomass and providing ground cover, the sale of eucalyptus poles and products has substantial potential to raise farm incomes, reduce poverty, increase food security and diversify smallholder-farming systems in less-favored areas of northern Ethiopia. "Despite the potential for eucalyptus to improve rural livelihoods in northern Ethiopia in 1997, the regional government of Tigray imposed a ban on eucalyptus tree planting on farmlands. This ban is related to concerns regarding potential negative environmental externalities associated with eucalyptus and also due to the desire to reserve productive farmland for crop production. The regional government promotes planting of eucalyptus and other species in community woodlots, and has recently begun to allow private planting of eucalyptus on community wasteland and steep hillsides. "In this paper, we review the debate about the ecological impacts of eucalyptus trees, as well as the economic factors that influence whether smallholders invest in these trees. Ex ante benefit-cost analysis based on community level survey data from Tigray illustrates that under most conditions planting eucalyptus trees yields high rates of return, well above 20% under most circumstances. The effect of variable harvest rates, the costs of decreased crop production when eucalyptus trees are planted on farmlands, and differences between administrative zones are considered relative to our base case in our rate of return estimates. The importance of fast growing tree species that can accommodate the high discount rates associated with smallholders in this region is emphasized. "Based upon the review of ecological and economic impacts of eucalyptus, several policy options are considered. The policy option with the largest potential economic benefits appears to be increasing allocation of wastelands for private tree planting. This option could increase average household income and wealth substantially, and offers large potential direct benefits to landless and land poor households who could be priority recipients of such land. The ecological risks are limited and the potential ecological benefits are large since this option would be implemented in degraded areas. This and other options could help make eucalyptus growing an important pathway of development in northern Ethiopia."
Urban Forest and Rural Cities: Multi-sited Households, Consumption Patterns, and Forest Resources in Amazonia
(2008) Padoch, Christine; Brondizio, Eduardo; Costa, Sandra; Pinedo-Vasquez, Miguel; Sears, Robin R.; Siqueira, Andréa D.
"In much of the Amazon Basin, approximately 70% of the population lives in urban areas and urbanward migration continues. Based on data collected over more than a decade in two long-settled regions of Amazonia, we find that rural-urban migration in the region is an extended and complex process. Like recent rural-urban migrants worldwide, Amazonian migrants, although they may be counted as urban residents, are often not absent from rural areas but remain members of multi-sited households and continue to participate in rural-urban networks and in rural land-use decisions. Our research indicates that, despite their general poverty, these migrants have affected urban markets for both food and construction materials. We present two cases: that of acai palm fruit in the estuary of the Amazon and of cheap construction timbers in the Peruvian Amazon. We find that many new Amazonian rural-urban migrants have maintained some important rural patterns of both consumption and knowledge. Through their consumer behavior, they are affecting the areal extent of forests; in the two floodplain regions discussed, tree cover is increasing. We also find changes in forest composition, reflecting the persistence of rural consumption patterns in cities resulting in increased demand for and production of acai and cheap timber species."
Using Farm Trees for Fuelwood
(1983) Poulsen, Gunnar
"One of the foundation stones of forest management is forest mensuration - comprising primarily stocktaking of the standing volume of wood and assessment of the growth rate. The basic data for calculating volume are: diameter at breast-height (dbh), the height of the marketable part of the trunk or measurement to the top of tree, and the number of trees per unit area. The current annual increment is found by combining the volume figures with additional parameters for diameter and height growth. The motive for writing this article and for starting by describing the commonly used method for surveying forest resources is a nagging doubt concerning the suitability of this method for assessing the productive potential (in terms of wood) of farm trees and drawing conclusions on this basis concerning the wood supply situation, the need for afforestation, etc."

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