Long term post-fire vegetation dynamics in north-east Mediterranean ecosystems. The case of Mount Athos Greece

Fire is an ecological and disturbance factor with a significant historical role in shaping the landscape of fire-prone environments. Despite the large amount of literature regarding post-fire vegetation dynamics, the north-east Mediterranean region is rather underrepresented in the literature. Studies that refer to the early post fire years and long term research are rather scarce. The current study is conducted in the socially and geographically isolated peninsula of Mount Athos (Holly Mountain) in northern Greece, and it studies vegetation dynamics over a period of 30 years since the last fire. Field data were collected 11 years since the event and were used to identify the present plant communities in the area, using TWINSPAN, and the factors affecting their distribution using CART. Four Landsat (TM, ETM, OLI) images are employed for the calculation of NDVI, which was found effective in detecting the intercommunity variation in the study area, and it is used for long term monitoring. The study includes four communities, from maquis to forest which are common in the Mediterranean region covering a wide altitudinal range. The results suggest that fire affects the various communities in a different way and their recovery differs significantly. While forest communities recover quickly after fire, maintaining their composition and structure, the maquis communities may need several years before reaching the pre-fire characteristics. The dry climatic conditions of the study area are probably the reason for the slow recovery of the most fire prone communities. Given that climate change is expected to make the conditions even drier in the region, studies like this emphasize the need to adopt measures for controlling wildfires and preventing ecosystem degradation

Conserving predators across agricultural landscapes in Colombia: habitat use and space partitioning by jaguars, pumas, ocelots, and jaguarundis

Habitat loss and degradation continue to increase across the tropics. Consequently there is an urgent need to understand their effects, as well as species’ habitat requirements and distribution within human-modified landscapes, in order to reconcile agricultural expansion with the conservation of endangered and keystone species, like the felids. We combined camera trapping and remote sensing-generated data into occupancy modelling to study the habitat use and space partitioning by four sympatric felids across an agricultural landscape in Colombia. The area includes cattle ranching and oil palm cultivation, an emerging land use in the Neotropics. Strong determinants of species occupancy were wetlands for jaguars (positive effect); water proximity (positive effect) for pumas; and pasture (negative effect) for ocelots and jaguarundis. Felid species except ocelots were never recorded in oil palm areas. Our results suggest that to align development with the conservation of top predators it is key to maintain areas of forest and wetland across agricultural landscapes and targeting agricultural and oil palm expansion to already-modified areas like pastures, which showed limited conservation value in the region. Lastly, as there was no spatial segregation between the studied felid species, conservation strategies to simultaneously benefit this guild seem possible even in modified landscape

Mid-term effects of fire on soil properties of North-East Mediterranean ecosystems

Fire is a fundamental ecological process with a long history on Earth, determining the distribution of vegetation formations across the globe. Fire, however, does not only affect the vegetation but also the soil on which vegetation grows, creating a post-fire environment that differs significantly in terms of soil chemical and physical properties from the pre-fire environment. The duration of these alterations remains largely unknown and depends both on the vegetation condition and the fire characteristics. In the current study, we investigate the effect of fire on some chemical and physical properties 11 years after the event in four plant communities. Two of them constitute typical Mediterranean fire-prone plant communities, dominated by sclerophyllous Mediterranean shrubs, such as Quercus coccifera and Q. ilex, while the other two are not considered fire prone and are dominated by deciduous broadleaved species such as Q. petraea and Castanea sativa, respectively. The results indicate that fire affects the soil properties of the various communities in a different manner. Burned sites in the Q. coccifera community have a significantly lower concentration of organic matter, total nitrogen, and available magnesium. At the same time, they have a significantly higher concentration of sand particles and a lower concentration of clay particles. The effect of fire on the soil properties of the other three communities is less dramatic, with differences only in total phosphorus, organic matter, and total nitrogen. The results are discussed in relation to the site conditions and the post-fire regeneration of plant communities

From Pillars to AI Technology-Based Forest Fire Protection Systems

The importance of forest environment in the perspective of the biodiversity as well as from the economic resources which forests enclose, is more than evident. Any threat posed to this critical component of the environment should be identified and attacked through the use of the most efficient available technological means. Early warning and immediate response to a fire event are critical in avoiding great environmental damages. Fire risk assessment, reliable detection and localization of fire as well as motion planning, constitute the most vital ingredients of a fire protection system. In this chapter, we review the evolution of the forest fire protection systems and emphasize on open issues and the improvements that can be achieved using artificial intelligence technology. We start our tour from the pillars which were for a long time period, the only possible method to oversee the forest fires. Then, we will proceed to the exploration of early AI systems and will end-up with nowadays systems that might receive multimodal data from satellites, optical and thermal sensors, smart phones and UAVs and use techniques that cover the spectrum from early signal processing algorithms to latest deep learning-based ones to achieving the ultimate goal

Synergies for Improving Oil Palm Production and Forest Conservation in Floodplain Landscapes

Lowland tropical forests are increasingly threatened with conversion to oil palm as global demand and high profit drives crop expansion throughout the world’s tropical regions. Yet, landscapes are not homogeneous and regional constraints dictate land suitability for this crop. We conducted a regional study to investigate spatial and economic components of forest conversion to oil palm within a tropical floodplain in the Lower Kinabatangan, Sabah, Malaysian Borneo. The Kinabatangan ecosystem harbours significant biodiversity with globally threatened species but has suffered forest loss and fragmentation. We mapped the oil palm and forested landscapes (using object-based-image analysis, classification and regression tree analysis and on-screen digitising of high-resolution imagery) and undertook economic modelling. Within the study region (520,269 ha), 250,617 ha is cultivated with oil palm with 77% having high Net-Present-Value (NPV) estimates ($413/ha?yr–$637/ha?yr); but 20.5% is under-producing. In fact 6.3% (15,810 ha) of oil palm is commercially redundant (with negative NPV of $-299/ha?yr-$-65/ha?yr) due to palm mortality from flood inundation. These areas would have been important riparian or flooded forest types. Moreover, 30,173 ha of unprotected forest remain and despite its value for connectivity and biodiversity 64% is allocated for future oil palm. However, we estimate that at minimum 54% of these forests are unsuitable for this crop due to inundation events. If conversion to oil palm occurs, we predict a further 16,207 ha will become commercially redundant. This means that over 32,000 ha of forest within the floodplain would have been converted for little or no financial gain yet with significant cost to the ecosystem. Our findings have globally relevant implications for similar floodplain landscapes undergoing forest transformation to agriculture such as oil palm. Understanding landscape level constraints to this crop, and transferring these into policy and practice, may provide conservation and economic opportunities within these seemingly high opportunity cost landscapes

Richness, diversity, and factors influencing occupancy of mammal communities across human-modified landscapes in Colombia

As human-modified landscapes are increasing in the tropics, it becomes critical to understand how they affect mammal communities to reconcile conservation and development. We combined land cover information and camera-trapping data to explore the effects of agricultural expansion on mammals in the Magdalena river valley of Colombia. We estimated species diversity, evenness, and dominance across two agricultural landscapes, modified by cattle ranching and oil palm cultivation. We further assessed which variables influence species- and community-level occupancy using multi-species occupancy models. Results highlight that modified landscapes display lower species richness, diversity and evenness, and higher dominance than more pristine sites. Residual forest cover and distance to water had significant effect on community occupancy (positive and negative respectively). Forests were particularly important for pumas, ocelots, lowland pacas, Central American agoutis, and crab-eating raccoons while wetlands had a positive effect on jaguars, the apex predator in the region. The influence of anthropogenic pressure was not clearly evident, though pastures were not valuable habitats for any mammal species, as they had a negative, yet not significant, effect on species and community occupancy. In light of rapidly expanding agriculture across the tropics, our findings highlight species-specific responses to disturbance that can inform land use planning and conservation policies. We stress the conservation value of forest and wetland habitat to mammal occupancy in heterogeneous ecosystems. Moreover, our results demonstrate that oil palm and crop expansion should target existing pastures, which displayed limited conservation value for Neotropical mammals but occupy vast swathes of land across Latin America

Identifying Where REDD+ Financially Out Competes Oil Palm in Floodplain Landscapes Using a Fine-Scale Approach

Reducing Emissions from Deforestation and forest Degradation (REDD+) aims to avoid forest conversion to alternative land-uses through financial incentives. Oil-palm has high opportunity costs, which according to current literature questions the financial competitiveness of REDD+ in tropical lowlands. To understand this more, we undertook regional finescale and coarse-scale analyses (through carbon mapping and economic modelling) to assess the financial viability of REDD+ in safeguarding unprotected forest (30,173 ha) in the Lower Kinabatangan floodplain in Malaysian Borneo. Results estimate 4.7 million metric tons of carbon (MgC) in unprotected forest, with 64% allocated for oil-palm cultivations. Through fine-scale mapping and carbon accounting, we demonstrated that REDD+ can outcompete oil-palm in regions with low suitability, with low carbon prices and low carbon stock. In areas with medium oil-palm suitability, REDD+ could outcompete oil palm in areas with: very high carbon and lower carbon price; medium carbon price and average carbon stock; or, low carbon stock and high carbon price. Areas with high oil palm suitability, REDD + could only outcompete with higher carbon price and higher carbon stock. In the coarse-scale model, oil-palm outcompeted REDD+ in all cases. For the fine-scale models at the landscape level, low carbon offset prices (US $3 MgCO2e) would enable REDD+ to outcompete oil-palm in 55$27 million to secure these areas for 25 years. Higher carbon offset price (US $30 MgCO2e) would increase the competitiveness of REDD+ within the landscape but would still only capture between 69$380–416 million in carbon financing. REDD+ has been identified as a strategy to mitigate climate change by many countries (including Malaysia). Although REDD+ in certain scenarios cannot outcompete oil palm, this research contributes to the global REDD+ debate by: highlighting REDD+ competitiveness in tropical floodplain landscapes; and, providing a robust approach for identifying and targeting limited REDD+ funds

Object-oriented methods for habitat mapping at multiple scales - Case studies from Northern Germany and Wye Downs

This paper presents an application of object-oriented techniques for habitat classification based on remotely sensed images and ancillary data. The study reports the results of habitat mapping at multiple scales using Earth Observation (EO) data at various spatial resolutions and multi temporal acquisition dates. We investigate the role of object texture and context in classification as well as the value of integrating knowledge from ancillary data sources. Habitat maps were produced at regional and local scales in two case studies; Schleswig-Holstein, Germany and Wye Downs, United Kingdom. At the regional scale, the main task was the development of a consistent object-oriented classification scheme that is transferable to satellite images for other years. This is demonstrated for a time series of Landsat TM/ETM+ scenes. At the local scale, investigations focus on the development of appropriate object-oriented rule networks for the detailed mapping of habitats, e.g. dry grasslands and wetlands using very high resolution satellite and airborne scanner images. The results are evaluated using statistical accuracy assessment and visual comparison with traditional field-based habitat maps. Whereas the application of traditional pixel-based classification result in a pixelised (salt and pepper) representation of land cover, the object-based classification technique result in solid habitat objects allowing easy integration into a vector-GIS for further analysis. The level of detail obtained at the local scale is comparable to that achieved by visual interpretation of aerial photographs or field-based mapping and also retains spatially explicit, fine scale information such as scrub encroachment or ecotone patterns within habitats

Biodiversity and Conservation of Forests

Forests are extremely valuable ecosystems, associated with a number of ecosystem services that are of significant importance for human wellbeing [...

Integrating Remote Sensing Methods and Fire Simulation Models to Estimate Fire Hazard in a South-East Mediterranean Protected Area

Unlike low intensity fire which promotes landscape heterogeneity and important ecosystem services, large high-intensity wildfires constitute a significant destructive factor despite the increased amount of resources allocated to fire suppression and the improvement of firefighting tactics and levels of organization. Wildfires also affect properties, while an increasing number of fatalities are also associated with wildfires. It is now widely accepted that an effective wildfire management strategy can no longer rely on fire suppression alone. Scientific advances on fire behavior simulation and the increasing availability of remote sensing data, along with advanced systems of fire detection can significantly reduce fire hazards. In the current study remote sensing data and methods, and fire behavior simulation models are integrated to assess the fire hazard in a protected area of the southeast Mediterranean region and its surroundings. A spatially explicit fire hazard index was generated by combining fire intensity estimations and proxies of fire ignition probability. The results suggest that more than 50% of the study area, and the great majority of the protected area, is facing an extremely high hazard for a high-intensity fire. Pine forest formations, characterized by high flammability, low canopy base height and a dense shrub understory are facing the most critical hazard. The results are discussed in relation to the need for adopting an alternative wildfire management strategy