Best practice tutorial on handling low-budget UAV finished

Best practice tutorial on handling low-budget UAV finished

Following the purchase and operaration of our two low-budget UAVs suring 2016 and 2017, a best practice tutorial of how to use the devices was written by Marius Röder, Steven Hill and Hooman Latifi, and it is now available in two English and German versions. This tutorial assumes no prior knowledge of the reader on handling low-budget Unmanned Aerial Vehicles in ecological and environmental contexts. It initially includes general infos on preperation and constellation of a typical UAV system, followed by instructions on planning and implementation of UAV flights using the available commercial software, importing the acquired imagery, relative orientation, optimization of camera parameters, generation of dense point clouds and finally digital surface modeling of the point clouds. The tutorial eventually includes lessons learned, tipps and tricks on further processing and potential applications of the UAV topographic products.
The tutorial can be retrieved here on Research Gate.

M.Sc. handed in on UAV-based monitoring of post-disturbed forest sites.

M.Sc. handed in on UAV-based monitoring of post-disturbed forest sites.

The M.Sc thesis by Marius Röder (Hochschule für Technik Stuttgart) was handed in. The thesis was supervised by Dr. Hooman Latifi and Prof. Eberhard Gülch and focuses on monitoring post-disturbed and heterogenuous forest sites by cost-effective methods from Unmaned Aerial Vehicle (UAV) domain. The advantage of normalized digital surface models extracted from UAV dta was initially compared to the products derived from standard aerial photography. Subsequently, the suitability of UAV-based inventory was compared to traditional eld methods . For this purpose, reference and UAV data were compared in terms of quality, quantity and cost eectiveness. In addition, an algorithm for automatic tree detection was compared to the manual detection on the UAV-imagery. The extent to which the results differ for certain forest heterogeneity as well as for single and grouped tree individuals was addressed., followed by a cost and benefit analysis of UAV-based forest inventory compared to traditional field-based methods.

 

UAV-based point cloud (left) and UAV-based nDSM (right) of an examplified sample plot in Bavarian Forest National Park

 

the results showed that the UAV inventory can not fully replace the eld methods in terms of quality and quantity due to the general disadvantages of photogrammetric methods in the small-scale forest sites consisting of dense rejuvenation stocks. However, from a purely economic point of view, the advantages over the eld method predominate. Improvements could be achieved by combining field and UAV-methods or a simulteanous use of digital camera and laser scanner mounted on UAV.

M.Sc. handed in on animal movement and remote sensing

M.Sc. handed in on animal movement and remote sensing

The M.Sc. thesis “Can animal movement and remote sensing data help to improve conservation efforts?” by Matthias Biber M.Sc. student within the Global Change Ecology program handed in his thesis. He explored the potential of remote sensing data to explain animal movement patterns and if these linkages can help to improve conservation efforts. He used Zebra as study animal in Southern and Eastern Africa. The second supervisor of his M.Sc. was Prof. Thomas Müller from BIK-F.

 

abstract:
Climate and land-use change have a growing influence on the world’s ecosystems, in particular in Africa, and increasingly threaten wildlife. The resulting habitat loss and fragmentation can impede animal movement, which is especially true for migratory species. Ungulate migration has declined in recent years, but its drivers are still unclear. Animal movement and remote sensing data was combined to analyse the influence of  various vegetation and water indices on the habitat selection of migratory plains zebras in Botswana’s Ngamiland. The study area experienced a more or less steady state in normalised difference vegetation index (NDVI) over the last 33 years. More than half of the study area was covered by PAs. NDVI increased stronger in PAs compared to areas that were not protected. NDVI was always higher in the Okavango Delta  compared to the Makgadikgadi Pans. Although zebras are thought to select for areas with high NDVI, they experienced a lower NDVI in the Makgadikgadi grasslands during wet season. Step selection functions (SSFs) showed that NDVI derived from Landsat as well as NDVI derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) were significant drivers of habitat selection across all individuals. Migration  seems to be driven by the high nutritional value of the Makgadikgadi grasslands and not seasonal resource limitation. Landsat imagery was shown to provide different environmental information compared to MODIS data. This highlights not only the importance of NDVI for explaining animal movement, but also the importance of Landsat imagery for monitoring habitat extent and fragmentation. Incorporating the animal’s  behavioural state and memory into SSFs will help to improve our ecological understanding of animal movement in the future.

M.Sc thesis: Agent-based modeling to understand Mediterranean wetland dynamic based on multiple remote sensing data

M.Sc thesis: Agent-based modeling to understand Mediterranean wetland dynamic based on multiple remote sensing data

M.Sc thesis (+ a two-month internship):

Agent-based modeling to understand Mediterranean wetland (former saltworks) dynamic based on multiple remote sensing data

 

UAV imagery over a portion of the study site. Image courtesy Cyril Fleurant (Uni Angers)

The Camargue’s former saltworks is a 6500-ha site located at the Mediterranean coast in southern France. The site has been recently purchased by the Conservatoire du Littoral, a public organization created in 1975 to ensure the protection of outstanding natural areas along the coast. The ongoing management of the area has been entrusted to the natural regional parc (PNR camargue), the national reserve of Camargue and the Tour du Valat. The site comprises a wide range of habitats. It has traditionally been home to the single colony of Flamingos nesting in France and is used by thousands of shorebirds during breeding and migration. Various construction works such as embankments (to control circulation of pumped sea-water through lagoons) and sea-front dike (to prevent uncontrolled flooding by the sea) together with salt exploitation and sea-level rise led to profound changes in the landscape that in turn call for the restoration of natural processes of coastal lagoon ecosystems. However, the conservation and management measures are restricted to be timely done as a result of difficult access for ground survey. Very high resolution remote sensing can introduce alternatives to this by providing continuous and objective surface coverage.

In this context, this M.Sc project aims at developing predictive tools on the basis of remote sensing data to follow habitat dynamics in order to help adaptive ecosystem management. The objective is to develop a method to understand the fast changes of the habitats using very high resolution remote sensing data. To this aim, LiDAR and very high resolution optical data (WorldView 2) and other GIS layers will be analyzed to produce spatially-continuous input for a state-of-the-art agent-based model. Few studies have applied this modeling approach to image analysis but the first results are promising .

Agent-based modeling will allow considering multiple non parametric factors that characterize the landscape dynamics. This approach will allow taking complex spatial and temporal processes as well as changing factors into account. The GAMA agent-based simulation platform (Taillandier et al. 2014, http://gama-platform.org/)  was initially developed to integrate GIS data in the  simulation. Within the envisaged M.Sc work this platform will be used for prediction based on the layers created from remote sensing data.

The M.Sc thesis is planned to be ideally started with a preliminary phase of two-month internship at the LETG, University of Angers . During the internship the M.Sc student will encompass a NetLogo and GAMA learning phase and gets to know the area and data.  A site visit at Tour du Valat research centre may help to understand the management objective of the area. The second phase would be the M.Sc thesis, during which the candidate will spend time at both Universities of Würzburg (4 months) and Angers (2 months). The stay in Angers is supported by an existing ERASMUS agreement between the two universities.

Interested candidates are wellcome to send an Email to Dr. Hooman Latifi.

Supervisors:

Dr. Aurélie Davranche (University of Angers, France)

Dr. Hooman Latifi (University of Würzburg)

Dr. Brigitte Poulin (Tour du Valat, France)

M.Sc. started on monitoring national parks

M.Sc. started on monitoring national parks

rp_EO-MOVE_sentinel_wuerzburg_birds_movement-286x300.jpgHenrike Schulte to Bühne started her M.Sc. „Quantifying landcover change using remote sensing data in a transboundary protected area“ in cooperation with the Zoological Society of London, Dr. Nathalie Pettorelli. Her M.Sc. is dealing with evaluating the status and change of nationalparks especially transboundary ones. Countries increasingly cooperate across boundaries for conservation purposes and these need to be evaluated and monitored constantly. Henrike is using remote sensing data to analyze environmental changes and is discussing the results with respect to conservation planning and political implications.

 

MSc thesis submitted by Joe Premier

MSc thesis submitted by Joe Premier

Jjoe_premeir_movement_graph_2016oe Premier submitted his M.Sc. thesis on “The Lynx Effect: Behaviour of Roe Deer in the Presence of Lynx in a European Forest Ecosystem” within the Global Change Ecology M.Sc. program. He was co-supervised by Marco Heurich from the Bavarian Forest Nationalpark. Predation risk is one of the main drivers of prey behaviour. In this study the behavioural responses of roe deer under the predation risk of lynx were investigated using a combination of spatial analysis and statistical analyses. Evidence for the hypothesis that roe deer exhibit avoidance behaviour to lynx locations both spatially and temporally could not be found, however the upper limit of avoidance behaviour was constrained to within 4 hours. It was hypothesised that the activity level of roe deer was driven by proximity to lynx, with activity levels increasing with decreasing separation distance. The activity level of roe deer was in general found not to be strongly driven by the variable distance to lynx. As hypothesised, the activity level of roe was associated with habitat, such that lower activity levels occurred in areas of highest visibility (low cover) and higher activity in lowest visibility (high cover). It was found in general that a LiDAR habitat index was the most important explanatory variable of roe deer activity level. In the specific case of the closest encounters (within 24 hours and 1Km) during the night, lynx’s most active time, activity level of roe deer was found to be elevated compared to less proximate individuals. There is also a suggestion that these roe deer move further than those more distant to lynx. The hypothesis that roe deer select habitats of lower predation risk when close to lynx was partially supported; it was found that roe deer selected lower predation risk areas when closest to lynx (within 24 hours and 1Km) during winter nights and consistently inhabited lower predation risk habitats during summer when compared to winter. Furthermore, it was shown that activity level was lower in high risk habitats as hypothesised. Under the predation risk of an ambush hunter, in this case lynx, it is suggested that roe deer adopt a “business as usual” behaviour, with energy diverted for anti-predator behaviour limited to scenarios of heightened risk. It is believed a near continuous GPS tracking schedule would be required to resolve lethal and non-lethal encounter events and illuminate avoidance behaviour and perception distance further.