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Knowledge on cheetah population densities across their current range is limited. Therefore, new and efficient assessment tools are needed to gain more knowledge on species distribution, ecology and behaviour. Scat detection dogs have emerged as an efficient and non-invasive method to monitor elusive and vulnerable animal species, like cheetahs, due to the dog’s superior olfactory system. However, the success of locating scat using detection dogs can be significantly improved under suitable weather conditions. We examined the impact of temperature, humidity and wind speed on detection rates of scat from cheetahs during a scat detection dog survey in Northern Kenya. We found that average wind speed positively influences the scat detection rate of detection dogs working on leash. Humidity showed no significant influence. Temperature showed a strong negative correlation with humidity and thus was excluded from our model analyses. While it is likely that wind speed is especially invalid for dogs working off leash, this study did not demonstrate this. Wind speed could thus influence the success of monitoring cheetahs or other target species. Our findings help to improve the survey and thus maximise the coverage of study area and the collection of target samples of elusive and rare species.

The increase in massive volumes of point data that are continuously being generated calls for more powerful solutions to analyze and explore this data. Very often, such data includes a direct or indirect reference to a location on the Earth and can then be referred to as ‘big geospatial data’. Maps are one of the best ways to assist humans with understanding geospatial relationships in such data. In this paper, we present a comprehensive workflow for generating all possible thematic map types from two-dimensional univariate big geospatial point data. The objective is twofold: to facilitate and support thematic map automation, and to make this information accessible to software developers. The workflow illustrates processing steps, design choices and dependencies between them based on the characteristics of input data. Processing steps and design choices that can be automated and those requiring human intervention are identified. The scope of the workflow in this paper was restricted to two-dimensional univariate geospatial point data and planar and true geometrical map depictions. The results presented in this paper support the development of geovisualization and geovisual analytics tools for big geospatial data.

Python programming and the application of web services technology can be considered important skills for geomatics students when looking for employment later. A course on Web Processing Services (WPS) as part of the International Geomatics master programme at Karlsruhe University of Applied Sciences takes this into consideration while using the opportunity of making students aware of less-known thematic mapping methods. Students are introduced to automating a complex geoprocessing task and finally wrapping it into a WPS. It is achieved by following the phases of first conceptualizing the single steps before then using ArcGIS ModelBuilder and Python scripts in combination to build the processing chain. The alternate band map method serves as example in the hands-on exercise. Later students are asked to automate the generation of the geometries for the map face and/or map legend supporting other thematic mapping methods like the square density map or the absolute value raster map. The paper discusses the teaching approach and experiences made so far. Conceptualizing the automatization of a given complex geoprocessing problem proved to be the most challenging part for the students.

The Faculty of Information Management and Media (IMM) at Karlsruhe University of Applied Sciences received funding for a project called ‘Fremdsein 4.0’. It targeted experiences about educational migration through applying various media means. Two interdisciplinary workshops were conducted focussing on the German words ‘Fremdsein’ and ‘Heimat’ as main topics, which relate to feelings of “foreignness” or of being at home. Among other results, two Web map apps that help to reflect on the two terms were conceptualized and evolved over time to become part of an exhibition towards the end of the project. The paper starts with describing the various contexts in which the map apps are placed: maps used in exhibitions, a reflection on ‘Fremdsein’, interdisciplinary learning and conceptualizing, and finally Web mapping and personalized maps. Next, the process of the map app development is covered, which led to two robust browser-based offline apps named ‘Ideal Home Finder’ and ‘Emotional Foreignness Ranking’. The former app, based on the research of Hofstede et al., makes use of empirically derived dimensions on cultural differences. By answering six questions, the user can find out in which countries he/she might feel at home. The latter app, which more directly resulted from workshop outcomes and personal experiences of the participants, allows to come up with rankings of emotional “foreignness” for five previously selected countries. We discuss and conclude with reflections on the two workshops, the developed apps and the exhibition.

Geospatial tools in a Web 2.0 environment can encourage citizens to engage with and influence their environment through online participation. In the field of geomatics, today’s students have to develop competencies in current technologies and learn how to adapt to continuously and rapidly changing technologies and applications. At the same time, we live in a globalized world where we increasingly deal with people from different backgrounds or have to commute to unknown places and environments for work. In this paper, we report about the experiences of students and lecturer participants from Germany and South Africa in a summer school on geomatics and participation, held in Karlsruhe, Germany, in July 2016. The starting point was to learn about nature conservation in Germany, particularly about the Rhine floodplains close to Rastatt. Mobile mapping apps were developed for this area with the aim of supporting conservation efforts. Confronting the participants with a new geographic area, a software development environment unknown to them and group work with participants from both universities has led to interesting insights beyond getting to know the partner university. From an evaluation of the summer school by participants, it was evident that the summer school succeeded in raising interest for participation in the student exchange programme and that participants expect clear guidance on the objectives of different activities. The balance between socializing and work provides a unique atmosphere for effective teaching and working, making a summer school such an enjoyable experience for students and lecturers.

Summary 1. It is important to document changes in the population sizes of species to justify and implement conservation programmes. This is often hampered by the absence of historical population count data, particularly for tropical animal species. 2. Here, we developed a predictive habitat distribution model (PHDM) for the army ant Dorylus wilverthi, a keystone species of Central African rainforests. We applied the model to forest cover data in western Kenya from 1913 to 2003 in order to estimate changes in the distribution and population size over the last century. The model was based on a large data set including abundance data of 51 repeatedly monitored 500 m transects in forest and non-forest habitats. 3. Forest cover within 1400 m of the transect lines explained 58% of the variation in abundance of D. wilverthi. The model predicts that the colony abundance of the army ant exponentially increases with increasing forest cover and that colonies are absent from landscapes with less than 11% forest cover. 4. Applying the PHDM to historical and recent forest cover data predicts a 52% decline in the population size of D. wilverthi (from 2801 to 1346 colonies) between 1913 and 2003. Under a worst-case scenario in which the forest area is reduced to the current national/nature reserves, the population size would decrease to fewer than 300 colonies, which is probably too low to ensure the long-term survival of the species. 5. Synthesis and applications. Our study demonstrates that the application of a PHDM on land-cover change time series data may give valuable insights into changes in the population size of species for which no historical population count data are available. Using this approach, we revealed a significant decline in population size of the army ant D. wilverthi over the last century. High protection status should be applied to all of the remaining forest area to prevent the population becoming regionally threatened and to facilitate long-term conservation of this keystone species in Kenya.

A means of deriving a disturbance index reflecting forest use history is demonstrated here to establish a disturbance gradient and enable comparison of different forest areas within and across individual forests. Detailed reference is made to Kakamega Forest in western Kenya for which a long-term time series has been established, although the study is spread to four further forests in Kenya and Uganda. A wide variety of sources are drawn upon for spatially resolved data that are integrated in a geographic information system. Three indices are derived: for commercial disturbance, local disturbance, and forest cover change. Results show a wide range of disturbance values (from low to heavy) for the research sites within Kakamega Forest, while results for Budongo and Mabira Forest sites show low and moderate levels, respectively. Correlations of low disturbance levels with nature or national reserves appear to be marked, while a correlation of disturbance with differing management authority is also suggested with Kenya Wildlife Service achieving the lowest disturbance levels. Results from the index are reviewed against other means of estimating disturbance with the conclusion that disturbance evaluations should be both spatially resolved and long-term in nature. Resume Nous montrons ici un moyen de deriver un indice de perturbation qui reflete l’utilisation historique d’une foret et qui permet d’etablir un gradient de perturbation et de comparer differentes zones forestieres au sein d’une meme foret ou entre des forets differentes. Une reference detaillee est faite a la Foret de Kakamega, dans l’ouest du Kenya, pour laquelle une suite de periodes a eteetablie dans le long terme, mais l’etude s’etend aussi a quatre autres forets en Ouganda et au Kenya. Une grande variete de sources ont servi a obtenir des donnees spatiales qui sont integrees dans un SIG. Trois indices en sont derives : pour la perturbation d’origine commerciale, la perturbation locale et le changement de couvert forestier. Les resultats revelent une large gamme de valeurs de perturbations (de faible aelevee) pour les sites de recherche dans la foret de Kakamega alors que les resultats pour les sites de Budongo et de Mabira presentent respectivement des taux faibles a moderes. Les correlations entre de faibles taux de perturbation et les reserves naturelles ou nationales semblent marquees alors qu’une correlation est aussi suggeree entre les perturbations et les differentes autorites de gestion, le Kenya Wildlife Service obtenant le plus faible taux de perturbation. Les resultats obtenus avec ces indices sont compares a d’autres moyens d’estimer les perturbations, avec la conclusion que les evaluations des perturbations devraient etre determinees spatialement et se faire sur le long terme dans la nature.

Summary Anthropogenic forest fragmentation and other kinds of human disturbance, such as selective logging, can reduce the diversity of plant and animal species. To evaluate the impact of fragmentation and small-scale disturbance on forest regeneration, we assessed species richness and total abundance of adult trees in comparison with seedlings in the heavily fragmented and disturbed Kakamega Forest, western Kenya. In nine differently disturbed 1-ha study blocks distributed across the main forest and fragments, we mapped all trees >10 cm in diameter at breast height. Additionally, we established ninety 1-m 2 seedling plots within these 1-ha study blocks which were monitored over 2.5 years. We recorded altogether 74 species of adult trees (30–43 per block) and 64 seedling species (24–41 per block). Neither fragmentation nor small-scale disturbance had an impact on adult tree species richness or total tree abundance. Yet, fragmentation and especially small-scale disturbance significantly reduced seedling species richness, particularly of late-successional species. While human impact did not affect diversity of adults, the impoverished species richness of seedlings suggests a reduced potential for regeneration and a loss of tree diversity in the long-term.

Biodiversity in tropical rainforests is heavily influenced by land use/cover change (LUCC), but so far there have been few LUCC studies conducted in Africa. We present several methods that make use of remotely sensed data and landscape metrics and allow for assessment of the development of land cover and thus forest fragmentation and disturbance over a substantial period of time. The study covers Kakamega Forest and its associated forest areas in western Kenya, over the last 30 years. The accuracy of a supervised multispectral classification of Landsat time series data encompassing seven time steps between 1972 and 2001 is numerically assessed using ground truth reference data considering the 2001 time step. Here, buffering the forest areas by 1 km, highest user's accuracies for the forest classes ‘near natural + old secondary forest’ (87.50%), ‘secondary forest’ (80.00%) and ‘bushland/shrubs’ (81.08%) are revealed. Images of a spatially distributed fragmentation index derived from the land cover time series by applying a three by 3 pixel-sized moving window to determine forest pixels’ adjacency, highlight trends in forest fragmentation, e.g. the splitting into two separate forests along the Yala/Ikuywa corridor. Calculations of mean fragmentation indices for the Biodiversity Monitoring Transect Analysis in Eastern Africa (BIOTA-East Africa) focus research areas are used to evaluate the fragmentation index and to demonstrate its potential to extrapolate (e.g. biological) field findings in space and time. Here we argue for a correlation of the fragmentation indices results not only with forest management regimes, but with population distribution and accessibility (e.g. by roads). A cluster analysis applying the isodata-algorithm on the classification results of all seven times steps allows for a rapid visual assessment of the distinct pattern of typical land cover development trends since 1972. This reveals that parts of Kakamega Forest have experienced severe forest loss while others, especially in the north-east, show signs of succession. Resume La biodiversite des forets pluviales tropicales est fort influencee par les changements d'utilisation et de couverture du sol (land use/cover change– LUCC), mais il y a eu jusqu’a present fort peu d’etudes des LUCC en Afrique. Nous presentons plusieurs methodes qui utilisent des donnees de teledetection et d’ecologie spatiale et permettent d’evaluer le developpement du couvert forestier et donc de la fragmentation et des perturbations durant une periode substantielle. L’etude concerne la foret de Kakamega et toute les zones forestieres qui lui sont associees dans l'ouest du Kenya, au cours des 30 dernieres annees. L'exactitude d'une classification multispectrale de donnees sur des series temporelles Landsat, qui regroupent sept etapes chronologiques entre 1972 et 2001, est evaluee numeriquement en utilisant les donnees reelles de «verite terrain» correspondant a l’etape de 2001. En quadrillant la foret en unites d'un km de cote, l'utilisateur obtient les plus grandes precisions pour les classes de forets «presque naturelle + ancienne foret secondaire» (87,50%), «forets secondaires» (80,00%) et «Brousse/buissons» (81,08%). Des images de l'index de fragmentation spatialement distribue, derivees de series temporelles de la couverture du sol en appliquant une fenetre glissante de trois pixels sur trois pour determiner l'adjacence des pixels, mettent en evidence les tendances de la fragmentation de la foret, par exemple la separation en deux forets separees le long du corridor Yala/Ikuywa. Les calculs des indices de fragmentation moyens pour les zones centrales de recherche de BIOTA-est servent aevaluer l'indice de fragmentation et a demontrer son potentiel pour extrapoler des decouvertes (ex. biologiques) de terrain dans l'espace et le temps. Nous defendons ici une correlation des resultats des indices de fragmentation non seulement avec les regimes de gestion forestiere, mais aussi avec la distribution de la population et l'accessibilite (routes). Une analyse d'ensemble appliquant l'algorithme de seuillage aux resultats de l'application des sept etapes permet une evaluation visuelle rapide du pattern distinct des tendances typiques du developpement de la couverture vegetale depuis 1972. Ceci revele que des parties de la foret de Kakamega ont connu de graves pertes forestieres alors que d'autres, specialement au nord-est, presentent des signes de succession.

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich. This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively. Understanding the causes and effects of species invasions is a priority in ecology and conservation biology. One of the crucial steps in evaluating the impact of invasive species is to map changes in their actual and potential distribution and relative abundance across a wide region over an appropriate time span. While direct and indirect remote sensing approaches have long been used to assess the invasion of plant species, the distribution of invasive animals is mainly based on indirect methods that rely on environmental proxies of conditions suitable for colonization by a particular species. The aim of this article is to review recent efforts in the predictive modelling of the spread of both plant and animal invasive species using remote sensing, and to stimulate debate on the potential use of remote sensing in biological invasion monitoring and forecasting. Specifically, the challenges and drawbacks of remote sensing techniques are discussed in relation to: i) developing species distribution models, and ii) studying life cycle changes and phenological variations. Finally, the paper addresses the open challenges and pitfalls of remote sensing for biological invasion studies including sensor characteristics, upscaling and downscaling in species distribution models, and uncertainty of results.

For the region St-Martin-de-Londres (southern France), information on vegetation formations is available for 5 different years between 1946 and 1979. Isoprenoid emission factors are assigned according to dominant plant species that were related to the vegetation formations. Potential isoprenoid emissions are simulated with the help of the Solar Radiation Model (SORAM) considering spatial effects of the complex terrain as well as temporal effects of photosynthetically active radiation and surface temperature, the main controlling parameters for biogenic volatile organic compound (BVOC) emission. The SORAM is embedded in a geographic information system environment and considers a digital elevation model of the modeling domain. Results illustrate long-term changes of emission fluxes due to plant succession between 1946 and today. By comparing the daily amount of isoprenoid emissions over a time period of 34 years, today's totals have increased by a factor of 4.4 as compared to the 1946 modeling results. The results presented give an example of possible impact of increasing natural plant cover on isoprenoid emissions for the Mediterranean region. These scenarios at the landscape level further emphasize the need for detailed information concerning vegetation (species, distribution, coverage, biomass) as well as the need for reliable emission factors in order to improve inputs of potential BVOC emissions to tropospheric chemistry models.

The rapid disruption of tropical forests probably imperils global biodiversity more than any other contemporary phenomenon(1-3). With deforestation advancing quickly, protected areas are increasingly becoming final refuges for threatened species and natural ecosystem processes. However, many protected areas in the tropics are themselves vulnerable to human encroachment and other environmental stresses(4-9). As pressures mount, it is vital to know whether existing reserves can sustain their biodiversity. A critical constraint in addressing this question has been that data describing a broad array of biodiversity groups have been unavailable for a sufficiently large and representative sample of reserves. Here we present a uniquely comprehensive data set on changes over the past 20 to 30 years in 31 functional groups of species and 21 potential drivers of environmental change, for 60 protected areas stratified across the world's major tropical regions. Our analysis reveals great variation in reserve `health': about half of all reserves have been effective or performed passably, but the rest are experiencing an erosion of biodiversity that is often alarmingly widespread taxonomically and functionally. Habitat disruption, hunting and forest-product exploitation were the strongest predictors of declining reserve health. Crucially, environmental changes immediately outside reserves seemed nearly as important as those inside in determining their ecological fate, with changes inside reserves strongly mirroring those occurring around them. These findings suggest that tropical protected areas are often intimately linked ecologically to their surrounding habitats, and that a failure to stem broad-scale loss and degradation of such habitats could sharply increase the likelihood of serious biodiversity declines.

Processes of deforestation, known to threaten tropical forest biodiversity, have not yet been studied sufficiently in East Africa. To shed light on the patterns and causes of human influences on protected forest ecosystems, comparisons of different study areas regarding land cover dynamics and potential drivers are needed. We analyze the development of land cover since the early 1970s for three protected East African rainforests and their surrounding farmlands and assess the relationship between the observed changes in the context of the protection status of the forests. Processing of Landsat satellite imagery of eight or seven time steps in regular intervals results in 12 land cover classes for the Kakamega-Nandi forests (Kenya) and Budongo Forest (Uganda) whereas ten are distinguished for Mabira Forest (Uganda). The overall classification accuracy assessed for the year 2001 or 2003 is similarly high for all three study areas (81% to 85%). The time series reveal that, despite their protection status, Kakamega-Nandi forests and Mabira Forest experienced major forest decrease, the first a continuous forest loss of 31% between 1972/1973 and 2001, the latter an abrupt loss of 24% in the late 1970s/early 1980s. For both forests, the temporally dense time series show short-term fluctuations in forest classes (e.g., areas of forest regrowth since the 1980s or exotic secondary bushland species from the 1990s onwards). Although selectively logged, Budongo Forest shows a much more stable forest cover extent. A visual overlay with population distribution for all three regions clearly indicates a relationship between forest loss and areas of high population density, suggesting population pressure as a main driver of deforestation. The revealed forest losses due to local and commercial exploitation further demonstrate that weak management impedes effective forest protection in East Africa.

Today, graduates seek employment in a global marketplace, regardless of the country in which they studied. Comparing academic programs helps students, academics and employers to make informed decisions about study options, program offerings and the employment of recent graduates. In this study, we juxtapose geospatial technologyrelated programs at three universities located in Europe, Africa and America. Initially, the authors contributed information about these programs through a questionnaire comprising several open-ended questions about the origins and development of the respective programs. Subsequently, the proportional thematic compositions of programs at the three universities were compared. As expected, this study was not without challenges. From the outset, we struggled with agreeing on terminology and semantics. Results of the study indicate that there is not a one-size-fits-all strategy for establishing, shaping and sustaining such programs. Program composition is guided by many factors, including staff expertise, university politics, legislation, attractiveness to students, technological developments, demands in the job market and requirements set by a professional body. Some of these factors are strongly influenced by the local (university) environment (e.g. staff expertise), others are of national relevance (e.g. legislation and a national professional body), while some apply globally (e.g. technological developments). The study illustrated how a comparison of proportional program composition can reveal significant differences and similarities that are not obvious when only content is compared. The compositional differences naturally result in graduates with different knowledge and skills that allow different career paths and meet different needs of the job market.

Water scarcity is among the many problems faced today by many countries in the world, especially African countries. The Kakamega area in western Kenya is known for plenty of rainfall (around 2000 mm annually), however, rainwater harvesting (RHW) from roofs is not yet a common practice in the region. In this study, we determined the potential of RWH as an alternative or preferred source of safe water for domestic use. Spatial modelling techniques using amount of rainfall, census data and detailed information available from the classification of very high resolution QuickBird satellite imagery as input data were applied to implement various approaches. Four conceptual models were developed at three different levels of detail: the Kakamega-Nandi forests area (3900 km²), the QuickBird imagery covered area (473 km² of farmland) and Buyangu village (1.9 km²). The four models were implemented in ArcGIS ModelBuilder and reveal the potential of such spatially explicit simulations to guide planners and to demonstrate the benefits of RWH to the local people. In the Kakamega-Nandi forests area, it rains enough to meet the annual water demand of 7300 l per person almost throughout the entire area.

Forest fragmentation and selective logging are two main drivers of global environmental change and modify biodiversity and environmental conditions in many tropical forests. The consequences of these changes for the functioning of tropical forest ecosystems have rarely been explored in a comprehensive approach. In a Kenyan rainforest, we studied six animal-mediated ecosystem processes and recorded species richness and community composition of all animal taxa involved in these processes. We used linear models and a formal meta-analysis to test whether forest fragmentation and selective logging affected ecosystem processes and biodiversity and used structural equation models to disentangle direct from biodiversity-related indirect effects of human disturbance on multiple ecosystem processes. Fragmentation increased decomposition and reduced antbird predation, while selective logging consistently increased pollination, seed dispersal and army-ant raiding. Fragmentation modified species richness or community composition of five taxa, whereas selective logging did not affect any component of biodiversity. Changes in the abundance of functionally important species were related to lower predation by antbirds and higher decomposition rates in small forest fragments. The positive effects of selective logging on bee pollination, bird seed dispersal and army-ant raiding were direct, i.e. not related to changes in biodiversity, and were probably due to behavioural changes of these highly mobile animal taxa. We conclude that animal-mediated ecosystem processes respond in distinct ways to different types of human disturbance in Kakamega Forest. Our findings suggest that forest fragmentation affects ecosystem processes indirectly by changes in biodiversity, whereas selective logging influences processes directly by modifying local environmental conditions and resource distributions. The positive to neutral effects of selective logging on ecosystem processes show that the functionality of tropical forests can be maintained in moderately disturbed forest fragments. Conservation concepts for tropical forests should thus include not only remaining pristine forests but also functionally viable forest remnants.

Fruiting trees in degraded areas are attractive for frugivorous birds and may become centers of regeneration. However, a number of tree species in degraded areas are exotic species. Thus, the question arises whether these exotic species can also act as foci for forest regeneration. In the farmland adjacent to Kakamega Forest, Kenya, we investigated the frugivore assemblage in, and seed rain and seedling establishment under, 29 fruiting exotic guava trees (Psidium guajava) at different distances to the forest. The results show that 40 frugivorous bird species visited guava trees. All of the seed and 82 percent of the seedling species found under the treecrowns were animal dispersed, 58 and 57 percent of them late-successional species, respectively. Path analysis revealed that the abundance of frugivorous birds, seeds, and seedlings did not decrease up to a distance of 2 km from the forest. Surprisingly, the abundance of frugivorous shrubland birds, animal-dispersed seeds, and late-successional seeds showed an increase with increasing distance from forest. Even though they are exotics, fruiting guava trees may have a positive effect on forest regeneration and might prove valuable for management plans concerning forest restoration.