To evaluate reforestation in farms: a tool for smallholders and the sustainability of their initiatives (EvaRefo)

Despite consensus on the necessity to reforest agricultural landscapes for climate change mitigation and adaptation, the experiences of many small landholders in reforestation are tarnished by difficulties leading to disillusionment and abandonment of initiatives. After clarifying with stakeholders of reforestation efforts in Balalaica, a biological subcorredor in Costa Rica, it became clear that the sustainability of an initiative depends on clear objectives, and a series of corresponding factors and well-timed decisions. In response to these needs, we elaborated a simple evaluation tool, EvaRefo. On the basis of indicator development, EvaRefo accounts for the different dimensions of reforestation sustainability as perceived by small landholder reforestation initiatives (ecological, economic, social and cultural). It distinguishes the potential of a reforestation initiative (whether favorable conditions are gathered) and its performance (how well are the trees growing and fulfilling expectations). The tool makes the most of scientific and technical knowledge on reforestation conditions and processes, while remaining operationally simple so that small landholders can use it without specific investment nor high-level technical knowledge. The self-evaluation of initiatives facilitates learning and capacity-building directly from field experience. EvaRefo was applied to six types of reforestation initiatives, focusing on different primary objectives, to visualize the kinds of tradeoffs that are involved by focusing on one goal rather than another: timber production, water conservation, ecological conservation, rural and scientific tourism, agroforestry, and payments for environmental services. Consistently low scoring indicators corresponded to aspects of associative and technical capacities, self-sufficiency, and species suitability, revealing that the farmer involved in reforestation often finds himself isolated to successfully manage his reforestation initiative. (Résumé d'auteur

The Evolution of Reforestation in Brazil

This paper analyzes the evolution of reforestation in Brazil and makes an evaluation of federal government policies used to stimulate that activity. Despite the huge increase of reforestation areas in Brazil since the 1970s, what put up Brazil as the sixth large country with reforested areas, a scarcity of roundwood from reforested areas is happing in that country during the first decade of the 21st century. Federal government implemented three programs to foster the reforestation in Brazil during the 1960s, 1970s and 1980s. However, nothing was implemented during the 1990s, when demand of roundwood increased, but not its production. This paper analyzes those programs, using a traditional cost-benefit approach. The results of that evaluation are used to suggest new federal government policies to foster the enlargement of reforestation in segments where price mechanism has not working well.

THE DYNAMICS OF LAND-COVER CHANGE IN WESTERN HONDURAS: SPATIAL AUTOCORRELATION AND TEMPORAL VARIATION

This paper presents an econometric analysis of land-cover change in western Honduras. Ground-truthed satellite image analysis indicates that between 1987 and 1996, net reforestation occurred in the 1,015.12 km2 study region. While some reforestation can be attributed to a 1987 ban on logging, the area of reforestation greatly exceeds that of previously clear-cut areas. Further, new area was also deforested between 1987-1996. Thus, the observed land-cover changes most likely represent a complex mosaic of changing land-use patterns across time and space. We estimate a random-effects probit model to capture drivers of land-cover change that are spatial, temporal or both. We employ two techniques to correct for spatial error dependence in econometric analysis suitable to qualitative dependent variables. Lastly, we simulate the impact of anticipated changes in transportation costs on land cover. We find that market accessibility, increase in national coffee prices, and agricultural suitability are the most important determinants of recent land-cover change.Land Economics/Use,

Participatory design and use of a simplified landscape in a simulation model for mitigating land use conflict in Northern Thailand highlands

Landscape modelling integrating spatial information in Geographic Information Systems has been widely used to represent knowledge and support decision-making in the field of natural resource management. However, creating suitable visual representations of the landscape and its dynamics to stimulate the participation of diverse stakeholders in co-management of the land is still needed. This paper focuses on the design and implementation of a virtual landscape based on iconic representation used with herders and foresters, which both of them have contrasted perceptions on forest regeneration, to observe vegetation dynamics and emerging landscape features depending on different cattle and forest management strategies. This spatial interface was used during computerassisted Role-Playing Game sessions as part of a Companion Modelling process aiming at facilitating learning and support decision making among the concerned stakeholders in an upper watershed of northern Thailand. Before designing the spatial interface used in the model, an historical analysis of land use and land cover changes based on remote-sensed data was carried out, as well as a field survey on the impact of cattle grazing on vegetation dynamics. Then, the first set of vegetation states and their dynamics were produced and were validated with herders and foresters later. Thereafter, the simplified landscape representing landscape heterogeneity was constructed and used in two gaming and simulation field workshops. The different patterns of landscape emerged from herders' and foresters' decisions and interactions stimulated them to think about how to manage agro-ecosystems. Both of them agreed to implement a pilot plot of Brachiaria ruziziensis pasture in reality after finish the second workshop. This process proved to be instrumental in facilitating communication among the parties in conflict and increasing their motivation to improve the current situation. However, the use of such virtual landscape in gaming sessions proved to be time consuming and the managed area as well as the number of players was limited. Therefore, to get rid of these constraints, a fully autonomous Agent-Based Model making use of the same kind of simplified virtual landscape will be developed and used with local stakeholders to run possible future scenarios of change in a more time efficient and inclusive way. (Résumé d'auteur

Efficiency analysis of Policies against desertification by applying DEA: a case study in the river Guadalentin catchment (Almeria, Spain)

This paper deals about an attempt to evaluate the different policies against desertification carried out during a twenty five year period (1978-2003) in the eight municipalities which compound the river Guadalentín catchment (Murcia, Spain). The approach is based on DEA and the European Environmental Agency indicator studies, the former to measure the efficiency and the second to select the best environmental indicators. The analysis has been reiterated with three different sets of outputs related to the different levels and aspects of the desertification process- from the merely soil losses to the overall desertification process in which population losses are considered. As a result a set of efficiency indexes has been obtained for each municipality, which show clearly the contribution of each action against desertification. These results are very valuable to establish future long term desertification policies in similar territories

Modelling and simulating change in reforesting mountain landscapes using a social-ecological framework

Natural reforestation of European mountain landscapes raises major environmental and societal issues. With local stakeholders in the Pyrenees National Park area (France), we studied agricultural landscape colonisation by ash (Fraxinus excelsior) to enlighten its impacts on biodiversity and other landscape functions of importance for the valley socio-economics. The study comprised an integrated assessment of land-use and land-cover change (LUCC) since the 1950s, and a scenario analysis of alternative future policy. We combined knowledge and methods from landscape ecology, land change and agricultural sciences, and a set of coordinated field studies to capture interactions and feedback in the local landscape/land-use system. Our results elicited the hierarchically-nested relationships between social and ecological processes. Agricultural change played a preeminent role in the spatial and temporal patterns of LUCC. Landscape colonisation by ash at the parcel level of organisation was merely controlled by grassland management, and in fact depended on the farmer's land management at the whole-farm level. LUCC patterns at the landscape level depended to a great extent on interactions between farm household behaviours and the spatial arrangement of landholdings within the landscape mosaic. Our results stressed the need to represent the local SES function at a fine scale to adequately capture scenarios of change in landscape functions. These findings orientated our modelling choices in the building an agent-based model for LUCC simulation (SMASH - Spatialized Multi-Agent System of landscape colonization by ASH). We discuss our method and results with reference to topical issues in interdisciplinary research into the sustainability of multifunctional landscapes

Negotiating the forest - farmland interface in northern Thailand with companion modelling

The debate about the expansion of agriculture in forest areas and the conservation or reforestation of head watersheds is still going on in montane Southeast Asia but in a rapidly changing context. Tremendous change occurred in the highland agrarian systems of northern Thailand during the past decades, leading to new farming practices, an increased diversity of stakeholders concerned by land management issues, and new relationships between villagers and national policies (decentralisation of resource management, shift from forest exploitation to conservation, etc.) and international conventions. In this context, the debate about the true participation of rural people in managing local renewable resources is taking central stage. New conceptual and practical tools to understand rural change in a more distributed, inclusive and interactive way have also emerged. System approaches relying on collaborative modelling are used to facilitate communication, knowledge sharing and the exchange of points of view among different types of stakeholders about a common resource management problem. The iterative and evolving Companion Modelling (ComMod) approach relies on multi-agent systems and makes use of the synergistic effects between role-playing games and computer agent-based models to co-construct simulation tools with stakeholders used in the joint exploration of possible future scenarios of their choice as part of negotiation processes leading to concrete action plans. In the past three years, such a ComMod process has been implemented in the head watershed of Nan province to understand the effects of recent change in forest management on the agrarian system and to mediate a land use conflict between foresters and Hmong herders. A preliminary diagnostic-analysis showed the influence of increased forest conservation efforts on the dynamics of deforestation in the local Hmong agrarian system. These land use dynamics were represented in a spatially explicit computer-assisted role-playing game. This tool was enriched and validated with the herders and foresters during a first set of gaming and simulation sessions aiming at the production of a shared representation of the problem at stake. The debate that followed identified innovative cattle management techniques to be tested and the simulation tool was modified to accommodate them. A second set of collaborative simulations tested the use of these innovations and led to an agreement on a joint experiment between herders and foresters seen as a first concrete step toward the co-management of the local forest -farmland interface. These results are discussed and the relevance of the approach, as well as the strengths and limitations of its main tools are assessed. Finally possible methodological improvements are suggested for collaborative modelling and simulation to better support the emergence of effective decentralized co-management of renewable resources in similar socio-ecological systems. (Résumé d'auteur

Trees and water: smallholder agroforestry on irrigated lands in Northern India

Trees / Populus deltoids / Agroforestry / Afforestation / Reforestation / Models / Water use / Water balance / Evapotranspiration / Precipitation / Remote sensing / Irrigation requirements / India

Carbon, land and water: a global analysis of the hydrologic dimensions of climate change mitigation through afforestation / reforestation

Climate change / Water supply / Forests / Land use / Afforestation / Reforestation / Water balance / Models / Evapotranspiration / Precipitation / Water use / Ecosystems

Natural recovery of genetic diversity by gene flow in reforested areas of the endemic Canary Island pine, Pinus canariensis

The endemic pine, Pinus canariensis, forms one of the main forest ecosystems in the Canary Islands. In this archipelago, pine forest is a mosaic of natural stands (remnants of past forest overexploitation) and artificial stands planted from the 1940's. The genetic makeup of the artificially regenerated forest is of some concern. The use of reproductive material with uncontrolled origin or from a reduced number of parental trees may produce stands ill adapted to local conditions or unable to adapt in response to environmental change. The genetic diversity within a transect of reforested stands connecting two natural forest fragments has been studied with nuclear and chloroplast microsatellites. Little genetic differentiation and similar levels of genetic diversity to the surrounding natural stands were found for nuclear markers. However, chloroplast microsatellites presented lower haplotype diversity in reforested stands, and this may be a consequence of the lower effective population size of the chloroplast genome, meaning chloroplast markers have a higher sensitivity to bottlenecks. Understory natural regeneration within the reforestation was also analysed to study gene flow from natural forest into artificial stands. Estimates of immigration rate into artificially regenerated forest were high (0.68-0.75), producing a significant increase of genetic diversity (both in chloroplast and nuclear microsatellites), which indicates the capacity for genetic recovery for P. canariensis reforestations surrounded by larger natural stands