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Land degradation is a globally recognized problem and restoration of degraded land is currently high on the international agenda. Forest landscape restoration and other restorative ecosystem management activities are important measures that contribute towards reaching the objectives of the Bonn Challenge, which aims to restore 350 million hectares by 2030. In this context, many restoration projects are being planned and implemented in Latin America and the Caribbean (LAC). We present an overview of the location, goals and activities, and an estimated climate change mitigation potential of 154 recent, ongoing and planned restoration projects in LAC. Our analysis suggests that most projects are located in the humid tropics and less attention is paid to drylands. Increasing vegetation cover, biodiversity recovery and recovery of ecological processes are the most common goals. Restorative activities to fulfil these goals were diverse and were related to the type and source of funding that projects receive. For example, projects implemented through the Forest Investment Program (FIP) and the Global Environment Facility (GEF) generally rely on natural or assisted regeneration over large areas (&gt, 20,000 ha), whereas Clean Development Mechanism (CDM) projects establish forest plantations, often including exotic monocultures, in smaller project areas (&lt, 5000 ha). Projects that are specifically implemented within the scope of Initiative 20 &times, 20 and other local initiatives that target the local environmental problems, are more varied and rely on a wider portfolio of restorative activities, such as erosion control, exclusion of grazing and mixed plantations. These projects are usually implemented in smaller project areas (&lt, 5000 ha). All projects had the potential to contribute to climate change mitigation by storing additional forest aboveground biomass through natural regeneration, assisted regeneration or establishing a plantation. Further analysis of the implemented activities is an important next step to investigate their effectiveness in terms of goals achieved under Initiative 20 &times, 20 and the Bonn Challenge. This would provide information for future restoration projects and upscaling of restorative activities in a wider area.

Restoring degraded lands is high on the international agenda and the number of restoration projects in Latin America and the Caribbean (LAC) has increased considerably over the past decades. However, the variety of approaches used have not been systematically documented and analyzed. We aimed to develop a restoration typology as a function of the geographical and socio-economical setting, planning, timeframe, finances, implementation, monitoring and potential impact, which will help to discern broad patterns and identify gaps in project implementation in LAC. We categorized 97 restoration projects using Multiple Correspondence Analysis and a Hierarchical Clustering on Principal Components. Three main restoration types emerged from the clustering, with the main defining variables being: (1) project area under restoration, (2) amount of funding received, (3) source of funding and (4) monitoring efforts. The first type are large-scale projects, which receive high amounts of funding provided by international donors, and with a well-established monitoring plan; the second type are projects financed with private money, typically lacking a sound monitoring program; and the third type represents small projects with low amounts of funding, financed with public funds from national governments, often with a rudimentary monitoring plan. The typology enables a comparative analysis of the status and trends of restoration activities across Latin America. We conclude that, despite growing awareness and recognition that integrated approaches are needed to revert complex and interconnected socio-economic and environmental issues like land degradation, the socio-economic dimension remains underexposed in the majority of restoration projects, whereas monitoring is still regarded as an extra cost instead of a necessary investment.

Mensajes principalesUna clasificacion multivariada de 97 proyectos de restauracion del paisaje forestal en America Latina y el Caribe revelo tres grupos definidos en base al (1) area del proyecto, (2) cantidad de financiamiento recibido, (3) fuente de financiamiento y (4) esfuerzos de monitoreo.El primer grupo lo componen proyectos de gran escala, que recibieron altas sumas para su financiacion por parte de donantes internacionales, y con planes de monitoreo bien establecidos; el segundo lo componen proyectos financiados con fondos privados, y sin un programa de monitoreo; y el tercer grupo esta representado por pequenos proyectos con bajo financiamiento que reciben fondos publicos de gobiernos nacionales y, con frecuencia, con planes de monitoreo incompletos.A pesar del creciente reconocimiento de la necesidad de implementar enfoques integrados para revertir complejos temas socioeconomicos y ambientales que se interconectan, como la degradacion de tierras, estos todavia no son visibles en la mayoria de los proyectos analizados; en tanto que el monitoreo aun es considerado como un costo adicional, en lugar de una inversion necesaria.

[1] Timber harvesting by clear cutting is known to impose environmental impacts, including severe disturbance of the soil hydraulic properties which intensify the frequency and magnitude of surface runoff and soil erosion. However, it remains unanswered if harvest areas act as sources or sinks for runoff and soil erosion and whether such behavior operates in a steady state or evolves through time. For this purpose, 92 small-scale rainfall simulations of different intensities were carried out under pine plantation conditions and on two clear-cut harvest areas of different age. Nonparametrical Random Forest statistical models were set up to quantify the impact of environmental variables on the hydrological and erosion response. Regardless of the applied rainfall intensity, runoff always initiated first and yielded most under plantation cover. Counter to expectations, infiltration rates increased after logging activities. Once a threshold rainfall intensity of 20 mm/h was exceeded, the younger harvest area started to act as a source for both runoff and erosion after connectivity was established, whereas it remained a sink under lower applied rainfall intensities. The results suggest that the impact of microtopography on surface runoff connectivity and water-repellent properties of the topsoil act as first-order controls for the hydrological and erosion processes in such environments. Fast rainfall-runoff response, sediment-discharge-hystereses, and enhanced postlogging groundwater recharge at catchment scale support our interpretation. At the end, we show the need to account for nonstationary hydrological and erosional behavior of harvest areas, a fact previously unappreciated in predictive models.

A comparative study on the impact of pine plantations on soil and vegetation development was conducted in the Ecuadorian Andes (3000–4000 m). Pine plantations of different ages under different types of management were compared with extensively grazed paramo grassland (the most common former land use) and natural forest (the formerly dominant vegetation in much of the life zone). No general impact of plantations was found, although some tendencies were identified that show that soils under pine plantations are drier and less organic. Moreover, the vegetation under pine plantations was similar to paramo grassland, though some examples of regeneration of Andean woody species were observed, as well as examples of plantations where understory was completely lacking. We concluded that the impact of pine plantations cannot be generalized but should be evaluated case by case while care is taken in implementing plantations until more knowledge is obtained about the effects on the ecosystem as a whole, esp...

For the semi-detailed characterization of inland valleys systems in the Ivory Coast, transect sampling was used to describe valley morphology, soils, and land use characteristics. Initially, for each valley one transect with a width of 200 to 400 m was proposed. More recently, use of a larger number of transects has been suggested. However, there is no statistical basis for either the number of transects to be described or their optimal width. Two sets of aerial photographs (1979, scale 1:50 000, and 1996, scale 1:20 000) of the Boundiali key area were processed and the results digitized. Using GIS, sets of transects with different width were made, and used for the determination of the sample size for estimating the land use ratio and the valley bottom ratio at valley system level with given confidence intervals. These results were validated with data from the field and with sets of pre-selected transects. The calculated sample size is based on simple random sampling and depends on both transect width and variability in the study area. For the characterization of inland valleys with reasonable confidence intervals, the sample size for random sampling is too large for the semi-detailed characterization method. Smaller samples of transects selected on the basis of sub-recent aerial photographs gave comparable results for land cover characteristics estimation as the larger samples for random sampling. There is scope for reducing sample size by formalizing criteria for transect placement on the basis of the earlier aerial photographs.

Interactions between erosion processes and soil and vegetation were studied in the three main ecosystems (i.e. sub-Andean valley, high Andean plateau and inter-Andean valley) in the southern Bolivian Andes. Erosion features such as badlands, dunes and stripped bedrock are widespread and reflect different scales of erosion in time, space and magnitude. The extent of active erosion features has been attributed mainly to land use change but geology and climate are also factors. The principle objective of this study was to characterise Erosion Sensitive Areas (ESAs) or physiographical units that are sensitive to erosion. Soil and vegetation properties provided insight into the relative importance of grazing as opposed to geology and climate in explaining the current extent of active erosion features. Erosion features, soil surface characteristics, biomass and chemical and physical soil properties from 36 sites distributed over 15 representative physiographical units were determined. In the areas that are most sensitive to erosion, the biomass of palatable species, soil organic matter (OM) content and available water (AW) are small and grazing density is low or moderate. The areas with high grazing density have large biomass of palatable species and large organic matter and available water contents. The distribution of the ESAs coincides with a semi-arid climate, low biomass of short grasses and very erodible parent material. Current reductions in grazing intensity do not seem to have resulted in less erosion. This suggests that past grazing history has altered the sensitivity to erosion, and the resilience of certain areas, to such an extent that erosion rates are high despite current low grazing intensity. It also suggests that contemporary degradation processes are not driven by current grazing densities but by climatic and geomorphological factors.