There is currently much interest in developing general approaches for mapping forest aboveground carbon density using structural information contained in airborne LiDAR data. The most widely utilized model in tropical forests assumes that aboveground carbon density is a compound power function of top of canopy height (a metric easily derived from LiDAR), basal area and…
Project Tag: 2010-2019
The microclimate mapping challenge
Organisms experience climate at a small scale, where the topography and the vegetation cause microclimates that vary greatly in space and time. The difference in temperature between north and south facing slopes of a mole hill on a hot summer’s day in Europe, for example, is comparable to the temperature difference between the Mediterranean and…
Canopy height mapping with drones
We have assessed the quality of three dimensional forest models produced from drone surveys, and conclude that concerns about their quality for canopy height and carbon measurement are unjustified. The rise of drones has been explosive. Rapid advances in technology and decreases in price have resulted in products that can be used off-the-shelf to survey…
Canopy structure and topography jointly constrain the microclimate of human‐modified tropical landscapes
Local‐scale microclimatic conditions in forest understoreys play a key role in shaping the composition, diversity and function of these ecosystems. Consequently, understanding what drives variation in forest microclimate is critical to forecasting ecosystem responses to global change, particularly in the tropics where many species already operate close to their thermal limits and rapid land‐use transformation…
Assessing the Progress of REDD+ Projects towards the Sustainable Development Goals
Almost a decade since the establishment of Reducing Emissions from Deforestation and Degradation (REDD+), this study investigates the extent to which REDD+ projects are delivering on the promise of co-benefits and the elusive ‘triple-win’ for climate, biodiversity, and local communities. The Climate, Community and Biodiversity Alliance (CCB) is among several leading REDD+ certification standards that…
A simple approach to forest structure classification using airborne laser scanning that can be adopted across bioregions
Reliable assessment of forest structural types (FSTs) aids sustainable forest management. We developed a methodology for the identification of FSTs using airborne laser scanning (ALS), and demonstrate its generality by applying it to forests from Boreal, Mediterranean and Atlantic biogeographical regions. First, hierarchal clustering analysis (HCA) was applied and clusters (FSTs) were determined in coniferous…
Estimating aboveground carbon density and its uncertainty in Borneo’s structurally complex tropical forests using airborne laser scanning
Borneo contains some of the world’s most biodiverse and carbon-dense tropical forest, but this 750 000 km2 island has lost 62 % of its old-growth forests within the last 40 years. Efforts to protect and restore the remaining forests of Borneo hinge on recognizing the ecosystem services they provide, including their ability to store and sequester carbon. Airborne laser scanning…
Effect of Tree Phenology on LiDAR Measurement of Mediterranean Forest Structure
Retrieval of forest biophysical properties using airborne LiDAR is known to differ between leaf-on and leaf-off states of deciduous trees, but much less is understood about the within-season effects of leafing phenology. Here, we compare two LiDAR surveys separated by just six weeks in spring, in order to assess whether LiDAR variables were influenced by…
Topography shapes the structure, composition and function of tropical forest landscapes
Topography is a key driver of tropical forest structure and composition, as it constrains local nutrient and hydraulic conditions within which trees grow. Yet, we do not fully understand how changes in forest physiognomy driven by topography impact other emergent properties of forests, such as their aboveground carbon density (ACD). Working in Borneo – at…
Blind image fusion for hyperspectral imaging with the directional total variation
Hyperspectral imaging is a cutting-edge type of remote sensing used for mapping vegetation properties, rock minerals and other materials. A major drawback of hyperspectral imaging devices is their intrinsic low spatial resolution. In this paper, we propose a method for increasing the spatial resolution of a hyperspectral image by fusing it with an image of…