Jens Oldeland

Jens Oldeland
Eco-Systems

PhD
Freelancing Ecologist and Independent Researcher @ IGDORE

About

166
Publications
95,290
Reads
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2,842
Citations
Citations since 2016
67 Research Items
1938 Citations
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Introduction
As a freelancing Environmental Data Scientists, my current research interests span all applied aspects of environmental and nature conservation. My methods and techniques used span a broad field from ecological statistics, modelling, biodiversity monitoring and analysis, remote sensing, GIS, and vegetation ecology. Right now I am working for several projects to analyse soil monitoring data, conduct SDMs for birds and biodiversity analysis of snails & reptiles. Feel free contacting me for a chat.
Additional affiliations
May 2020 - September 2022
Eco-Systems
Position
  • CEO
Description
  • I work as a freelancing environmental data scientist with my company called "Eco-Systems". I conduct statistical analysis and modelling of ecological data for academia, NGOs, ministries and the economy to support my customers to better understand their data and to achieve their goals with respect to improved environmental and nature conservation. I also provide courses in statistical modelling with R as well as courses in remote sensing / GIS. Website is coming soon.
June 2016 - October 2019
University of Hamburg
Position
  • Professor (Assistant)
Description
  • I worked at the University of Hamburg as a Assistant Professor (Akademischer Rat a.Z.) on a limited contract. Besides teaching statistics, ecology, and Remote Sensing/GIS courses, I conducted research on biodiversity and climate and land use change, invasive species ecology, application of drones and much more (notice the variability of topic in my articles).
September 2005 - September 2006
German Aerospace Center (DLR)
Position
  • PhD Student
Education
August 2005 - October 2010
University of Hamburg
Field of study
  • Vegetation Ecology, Remote Sensing, Biodiversity
August 2005 - October 2010
University of Hamburg
Field of study
  • Ecology

Publications

Publications (166)
Article
Full-text available
Edaphically unusual sites harbor a flora that is often unique in its taxonomic as well as functional composition and contain many endemic species. While this edaphic endemism, edaphism, has been discussed previously on various special soils, in this study we relate it for the first time to the floristic characteristics of so called “quartz islands”...
Article
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Trees can contribute to the reduction of atmospheric CO2 concentrations, but they do so at varying rates. The carbon sequestration rate (CSR) of trees is influenced by many factors including tree age, forest density, site conditions, and extreme events such as droughts and floods. This research reconstructs past carbon stocks of Pedunculate oak (Qu...
Article
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Psammotermes allocerus Silvestri, 1908 is the only described species representing the genus Psammotermes Desneux, 1902 in Southern Africa. The large geographical range of this subterranean termite covers both summer and winter rainfall regimes. Deadwood is the preferred food when available, but in more arid habitats, both live and dead grasses form...
Article
Welwitschia mirabilis, an endemic gymnosperm of the Namib Desert, has two subspecies: ssp. namibiana, found in Namibia, and the typical ssp. mirabilis occurring in Angola and Namibia. Despite decades of research little is known about the distribution and ecological preferences of this species. In this paper, we study the ecological niche and the ge...
Article
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Termite mounds contribute to the heterogeneity and productivity of many semi‐arid ecosystems worldwide. Regular spatial patterns of termite mounds are well documented but the underlying pattern‐building mechanisms remain to be clarified. This study analysed a comprehensive data set of Macrotermes michaelseni mound metrics, spatial patterns and dyna...
Article
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Understanding the ecological requirements and thresholds of individual species is crucial to better predict potential outcomes of climate change on species distribution. In particular, species optima and lower and upper limits along resource gradients require attention. Based on Huisman-Olff-Fresco (HOF) models, we determined species-specific respo...
Article
Island biogeography provides concepts for conservation management as fragmented habitats are comparable to ocean islands. Remote sensing can help to extract terrestrial habitat islands on the landscape scale. However, little is known about the effects of image resolution and classification algorithms on resulting island size and related parameters....
Article
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We report the introduction of the central and eastern European helicid land snail Caucasotachea vindobonensis in North America. It was first recorded from Rensselaer County in the state of New York in 2015 by a community scientist. From 2016 to 2020, 14 additional occurrences in Rensselaer County, neighbouring Albany County and an imprecisely local...
Article
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The waters around Iceland, bounding the Northern North Atlantic and the Nordic seas, are a region characterized by complex hydrography and seabed topography. This and the presence of the Greenland-Iceland-Faroe-Scotland ridge (GIFR) are likely to have a major impact on the diversity and distribution of the benthic fauna there. Biodiversity in this...
Article
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In many tropical ecosystems, termites are important ecosystem engineers. Mound‐building termite species often contribute to topographical landscape heterogeneity, and the associated accumulation of soil moisture and nutrients affects the spatial distribution of plant communities. Plants that grow next to the termite mound are known to benefit from...
Article
Flood and fire act as ecological filters which can interact to shape forest structure and species composition. Our objective was to investigate how the interaction between fire and flood influences richness, abundance, basal area and species composition of the tree community and the monodominant belts of Attalea phalerata Mart. in forest islets of...
Article
Full-text available
Questions Habitat islands are often characterized by the presence of more or less sharp boundaries to adjacent matrix habitats. However, knowledge on boundaries of natural habitat islands is scarce, especially regarding patterns of beta diversity and its two underlying components: species turnover and nestedness. We therefore aim to quantify the ef...
Article
Questions Inundation is an important feature linked to monodominance in tropical wetlands. The occurrence of neighbouring monodominant species indicates that soil can also have an important role. This study aimed to determine if variations in densities of three neighbouring monodominant species, Byrsonima cydoniifolia, Copernicia alba and Tabebuia...
Article
Full-text available
Aim: This study aimed to predict the alpha and beta plant diversity of an arid mountain based on environmental variables derived from remotely sensed and ground truth data. Location: Gebel Elba, Egypt Methods: Based on 133 vegetation plots of 100 m2, we calculated alpha (Shannon index) and beta [the first ordination axis of nonmetric multidimension...
Article
Full-text available
Plant species that negatively affect their environment by encroachment require constant management and monitoring through field surveys. Drones have been suggested to support field surveyors allowing more accurate mapping with just-in-time aerial imagery. Furthermore, object-based image analysis tools could increase the accuracy of species maps. Ho...
Article
While saltmarsh communities are endangered in many parts of the world due to anthropogenic impact, the risk of invasion by exotic plants is considered to be low because of their saline conditions. However, in urban areas, saltmarshes receive high nutrient freshwater input through stormwater discharge. We tested if invasion of saltmarsh by exotic pl...
Article
Full-text available
Welwitschia mirabilis is one of the most extraordinary plant species on earth. With a fossil record of 112 My and phylogenetically isolated within the order Gnetales, the monotypic genus Welwitschia has survived only in the northern Namib Desert in Angola and Namibia. Despite its iconic role, the biogeography, ecological niche, and evolutionary his...
Chapter
Monodominance is defined as a phenomenon whereby a single species can cover most of the terrain in comparison with other species. In tropical environments, monodominance can be considered as an odd phenomenon because of the high species diversity that is normally found in a single hectare. In the tropics, this phenomenon is more common in floodable...
Chapter
Fire in seasonally inundated floodplains sounds like a contradictory issue. Nevertheless, many tropical and subtropical wetlands in the world, such as Pantanal, are fire-prone. Fire can interact with inundation in these systems determining variation in their vegetation structure, functioning, and composition. This chapter aims to describe the fire...
Article
South African quartz fields in the Succulent Karoo and adjacent biomes are special habitats for a range of highly specialized dwarf succulents, many of which belong to the Aizoaceae. The soil chemistry of the quartz fields ranges from very acidic to slightly alkaline and from moderately to highly saline, and drives species turnover. The soil condit...
Article
Full-text available
Questions The arid Kalahari is prone to desertification as a result of climate change and / or land use. We analysed the effects of climatic variables and game herbivory on the vegetation composition to answer the question of how different life‐form types respond to climate, browsers and grazers as drivers of vegetation change. Location The study...
Article
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Background In arid environments, plant primary productivity is generally low and highly variable both spatially and temporally. Resources are not evenly distributed in space and time (e.g., soil nutrients, water), and depend on global (El Niño/ Southern Oscillation) and local climate parameters. The launch of the Sentinel2-satellite, part of the Eu...
Article
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Aims : Gebel Elba is an arid mountain range supporting biological diversity that is incomparable to any other region of Egypt. This mountain has a vegetation structure and floristic community similar to the highlands of East Africa and the southwestern Arabian Peninsula. We aimed to provide the first classification of the vegetation units on Gebel...
Article
Full-text available
Species–area relationships (SARs) are among the best investigated patterns in ecology, yet the shape of the function that should describe SARs and the biological meaning of the function parameters are disputed. Elevational gradients offer the opportunity of investigating how biodiversity responds to large variations in environmental characteristics...
Article
Globally, the intensification of land use for agriculture, timber and fuel is considered the leading threat to the diversity and biomass of forests and woodlands. To suggest management options, it is important to understand the patterns and drivers of diversity, structure, biomass and carbon stock of woodland vegetation. In this study we used data...
Article
Satellite remote sensing has greatly facilitated the assessment of aboveground biomass in rangelands. Soil-adjusted vegetation indices have been developed to provide better predictions of aboveground biomass, especially for dryland regions. Semi-arid rangelands often complicate a remote sensing based assessment of aboveground biomass due to bright...
Article
Full-text available
Disease management in agriculture often assumes that pathogens are spread homogeneously across crops. In practice, pathogens can manifest in patches. Currently, disease detection is predominantly carried out by human assessors, which can be slow and expensive. A remote sensing approach holds promise. Current satellite sensors are not suitable to sp...
Article
We studied elevation-richness pattern of vascular plants along an elevational gradient in four connected wadis of the arid mountain Gebel Elba, south-east of Egypt. We found a rare elevation-richness pattern for a low, arid mountain. The pattern is characterized by a strong increase in species richness and Shannon diversity at low elevations follow...
Article
Since 2010 Australian ecosystems and managed landscapes have been severely threatened by the invasive fungal pathogen Austropuccinia psidii. Detecting and monitoring disease outbreaks is currently only possible by human assessors, which is slow and labour intensive. Over the last 25 years, spectral vegetation indices (SVIs) have been designed to as...
Article
An important indicator of the rangeland health, associated with land degradation, is the ability of semi-natural rangelands to provide forage of sufficient quality for livestock production. In Qilian Mountains (Gansu Province, NW China) biomass production and forage quality are dependent on the seasonality of precipitation and temperature; most of...
Article
The Succulent Karoo biome is a renowned centre of biodiversity and endemism in the arid winter rainfall region of South Africa that is threatened by climate change. On 20 permanently marked plots within a biodiversity observatory, species richness and cover were assessed annually from 2002 to 2017 during the growing season. We were interested, firs...
Article
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Climate and environmental heterogeneity are currently discussed as the most important drivers of plant diversity along altitudinal gradients. Compared to functional diversity, taxonomic diversity has received much more attention in research on altitudinal gradients, although functional diversity may provide more information on the ecological mechan...
Article
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Modelling ecological niches across vast distribution ranges in remote, high mountain regions like the Himalayas faces several data limitations, in particular nonavailability of species occurrence data and fine-scale environmental information of sufficiently high quality. Remotely sensed data provide key advantages such as frequent, complete, and lo...
Article
Subtropical and temperate coastal saltmarsh of Australia is listed as an endangered ecological community under the Commonwealth Environment Protection and Biodiversity Conservation Act (EPBC Act). Saltmarshes are under threat from sea level rise, landward migration of mangroves, and in urban regions from habitat loss, input of litter, nutrients, an...
Article
Invasive plant species can have high, self-reinforcing impacts on ecosystem structure and functioning that induce permanent changes of ecosystem properties. Therefore, early detection and timely management is required to alleviate ecosystem consequences of invasion. Integrating airborne hyperspectral imagery with LiDAR data can deliver spatially ex...
Article
Full-text available
Abstract: Rangelands in arid areas of southern Africa are prone to degradation through overutilization. Once degraded, rangelands recover very slowly or may not recover without external drivers such as very high-rainfall years. To what extent, at what pace, and to which state Succulent Karoo vegetation is able to recover from long-term exposure to...
Article
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Seedling establishment is a crucial factor for spatial dynamics of treelines. However, safe sites for successful tree regeneration which is a basic prerequisite for a supposed treeline advance in response to climate warming have not been fully characterised, especially in the Himalayas. In this study, we aim at analysing safe sites of the tree spec...
Article
Hundreds of species in one of Australia's dominant plant families, the Myrtaceae, are at risk from the invasive pathogenic fungus Austropuccinia psidii. Since its arrival in Australia in 2010, native plant communities have been severely affected, with highly susceptible species likely to go extinct due to recurring infections. While severe impact o...
Article
The impact of invasive species may depend on the dissimilarity of their functional traits relative to the native community. Therefore, comparing species traits in a multidimensional space can help to better understand invader impacts, but novel methods are needed to effectively measure multiple traits across diverse plant communities. The main aim...
Article
Traditional pastoral practices in Kyrgyzstan have been transformed into more intensive forms of pastoral land use during the Soviet colonial period, and once again modified after independence in 1991. Kyrgyz winter pastures close to settlements are subject to degradation processes, while remote summer pastures are less affected. It is largely unkno...
Poster
Full-text available
Hundreds of species in one of Australia’s dominant plant families, the Myrtaceae, are at risk from the invasive pathogenic fungus Austropuccinia psidii. Since its arrival in Australia in 2010, native plant communities have been severely affected, with highly susceptible species likely to go extinct due to recurring infections. While severe impact o...
Chapter
Mapping tree species at the single-tree level is an active field of research linking ecology and remote sensing. However, the discrimination of tree species requires the selection of the relevant spectral features derived from imagery. We can extract an extensive number of image parameters even from images with a low spectral resolution, such as Re...
Article
Abstract Questions: Species composition and ecology of treeline vegetation types in the Rolwaling Valley is largely unknown to date. The aim of this study is to differentiate plant communities along the elevational gradient in the treeline ecotone, and to identify site factors which cause the differentiation of the treeline ecotone vegetation. Stud...
Article
Full-text available
Spatial heterogeneity of ecosystems crucially influences plant performance, while in return plant feedbacks on their environment may increase heterogeneous patterns. This is of particular relevance for exotic plant invaders that transform native ecosystems, yet, approaches integrating geospatial information of environmental heterogeneity and plant-...
Poster
Full-text available
for more details see the article: Elevation‐richness pattern of vascular plants in wadis of the arid mountain Gebel Elba, Egypt (DOI: 10.1111/aje.12593). This study identified a fourth form of altitude–species richness relationship for plants, namely a linear increase followed by a plateau. This pattern is interpreted to be caused a major stress gr...
Article
Full-text available
Questions: Species composition and ecology of treeline vegetation types in the Rolwaling Valley is largely unknown to date. The aim of this study is to differentiate plant communities along the elevational gradient in the treeline ecotone, and to identify site factors which cause the differentiation of the treeline ecotone vegetation. Study area: R...
Article
Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. In this context, we aim at investigating the sensitivity and responsiveness of the near-natural treeline ecotone in Rolwaling Himal,...
Article
Full-text available
Species richness is a widespread measure to evaluate the effect of different management histories on plant communities and their biodiversity. However, analysing the phylogenetic structure of plant communities could provide new insights into the effects of different management methods on community assemblages and provide further guidance for conser...
Article
We asked how historical and recent grazing intensity affect vegetation and soil characteristics in the patchy landscape of the heuweltjieveld in the semi-arid biodiversity hotspot Succulent Karoo. The study was carried out on the communal farmland of the Soebatsfontein community, 80 km south-west of Springbok, in Namaqualand (South Africa). Heuwelt...
Article
Environmental heterogeneity and plant–plant interactions are key factors shaping plant communities. However, the spatial dimension of plant–plant interactions has seldom been addressed in field studies. This is at least partially rooted in a lack of methods that can accurately resolve functional processes in a spatially explicit manner. Isoscapes,...
Article
Full-text available
Understanding interactions between native and invasive plant species in field settings and quantifying the impact of invaders in heterogeneous native ecosystems requires resolving the spatial scale on which these processes take place. Therefore, functional tracers are needed that enable resolving the alterations induced by exotic plant invasion in...
Data
Bayesian Information Criterion (BIC) as a function of number of clusters for plots 1–3. Ten different combinations of constraints for multivariate mixture models have been tested: EII = spherical, equal volume; VII = spherical, unequal volume; EEI = diagonal, equal volume and shape; VEI = diagonal, varying volume, equal shape; EVI = diagonal, equal...
Data
Georeferenced values of δ15N (‰), δ13C (‰) and N concentration (g N*kg-1) used to create isoscapes. (PDF)
Poster
Full-text available
Numerous studies based on passive acoustic monitoring by Porpoise Detectors (C-PODs) showed negative effects of pile driving by hydraulic hammers for the construction of offshore wind farms on harbour porpoise (Phocoena phocoena). We studied the efficiency of noise mitigation by two configurations of circular big bubble curtains (BBC1 & BBC2) regar...
Article
Cross-border studies offer unique situations to study the impact of different land-use regimes on ecosystems. Along the Angolan and Namibian border formed by the Okavango River, the environmental conditions and traditional land-use practises are the same on either side of the river. However, decades of civil war in Angola led to a stagnant developm...
Article
Full-text available
Inundation and fire can affect the structure of riparian vegetation in wetlands. Our aim was to verify if there are differences in richness, abundance, basal area, composition and topographic preference of woody species in riparian forests related to the fire history, flooding duration, or the interaction between both. The study was conducted in th...
Article
Full-text available
Climate change and engineering activities have modified the hydrology and morphology of estuaries. However, the potential effects of these modifications on vegetation succession in estuarine marshes are still poorly understood. Therefore, we studied temporal changes in tidal habitats of the Elbe estuary over a period of 30 years. We compared vegeta...
Article
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In many parts of Africa, spatially-explicit information on plant α-diversity, i.e., the number of species in a given area, is missing as baseline information for spatial planning. We present an approach on how to combine vegetation-plot databases and remotely-sensed land surface phenology (LSP) metrics to predict plant α-diversity on a regional sca...
Article
Full-text available
Hyperspectral remote sensing is an effective tool to discriminate plant species, providing vast potential to trace plant invasions for ecological assessments. However, necessary baseline information for the use of remote sensing data is missing for many high-impact invaders. Furthermore, the identification of the suitable classification algorithms...
Presentation
Full-text available
Puccinia psidii is an invasive pathogen of global significance. Discovered in Brazil in 1884, it spread over Florida, Hawaii, Japan, China and finally reached Australia in 2010. Plant pathologists regard P. psidii (myrtle rust) as a threat to native Australian Myrtaceae - dominated ecosystems, and to industries depending on this plant family (e.g....
Article
Full-text available
Epidermal structures (ES) of leaves are known to affect the functional properties andspectral responses. Spectral studies focused mostly on the effect of hairs or wax layers only. Westudied a wider range of different ES and their impact on spectral properties. Additionally, weidentified spectral regions that allow distinguishing different ES. We us...