My research

The main topics I’m working on at the moment are:

  • How does forest structure form, and can we design forests or management strategies to achieve particular outcomes, such as in production forestry, carbon storage or habitat creation for conservation.
  • Applications of 3D laser scanning to forest surveying, with a focus on describing the quantity and distribution of foliage.
  • Individual decision-making by plants based on their local spatial context within a population.

I’m always interested to hear from potential graduate students, post-doc fellows or collaborators, so if you want to know more then please get in touch.

Below is a more detailed summary of my research to date. Rather than a conventional publication list I’ve split it into broad themes with a quick introduction to where I am with each of them, followed by the progress so far. The ones near the top are things I’m actively working on and therefore have fewer papers, often with more preliminary findings. Lower down are projects that are either completed or shelved until I get a sabbatical*. For a more conventional profile see ResearchGate.

Me in my happy place. Look at all those trees! This is in central Kamchatka. Photo credit: Tim Kell.
Me in my happy place. Look at all those trees! This is in central Kamchatka. Photo credit: Tim Kell.

Emergent properties of spatially-structured natural systems

My main research interest at the moment is in how spatial patterns form in natural systems, particularly how localised interactions among individuals lead to the emergent structure of communities. This mostly looks at trees in forests but the fundamental principles can be applied to any species — I’m developing barnacles as an alternative study system. Many of the methods were first developed in physics, and it’s a joint program with former post-doc and physicist Jorge Velázquez, now at the University of Puebla in Mexico. Several manuscripts are in the pipeline and there’s plenty more to come, including field demonstrations of our models. Topics we’re investigating include mechanisms for species coexistence, the processes controlling size distributions, and population dynamics. Adding a spatial perspective causes systems to depart from predictions made at the population level, often leading to counter-intuitive outcomes.

Brearley F.Q., Mansur M. and Eichhorn M.P. (2023). Spatial patterning of Gonostylus brunnescens in eastern Borneo. Folia Oecologica 50, 55–59.

Velázquez-Castro J., and Eichhorn M.P. (2017). Relative ranges of mating and dispersal modulate Allee thresholds in sessile species. Ecological Modelling 359, 269–275. pdf and summary

Velázquez J., Allen R.B., Coomes D.A. and Eichhorn M.P. (2016). Asymmetric competition causes multimodal size distributions in spatially-structured populations. Proceedings of the Royal Society Series B 283, 20152404. pdf (you can read a summary of the paper here)

Hooper R.C.and Eichhorn M.P. (2016) Too close for comfort — spatial patterns in acorn barnacle populations. Population Ecology 58, 231–239. pdf and summary

Velázquez J., Garrahan J.P. and Eichhorn M.P. (2014). Spatial complementarity and the coexistence of species. PLOS ONE 9, e114979. pdf

Eichhorn M.P. (2010). Pattern reveals process: Spatial organisation of a Kamchatkan stone birch forest. Plant Ecology and Diversity 3, 281–288. pdf

Eichhorn M.P. (2010). Spatial organisation of a bimodal forest stand. Journal of Forest Research, 15, 391–397. pdf

velazquez
Lotka-Volterra competition models allow for coexistence of two species within a certain region of parameter space at the population scale (between the solid lines) but adding spatial interactions alters this. Here we vary inter-specific competition intensity and the intrinsic death rate of one species, but many parameter combinations generate similar patterns. In spatial simulations, when dispersal is long-ranged, outcomes match population-level predictions, and the range of competition is unimportant (a). When dispersal and competition are short-ranged, the zone of coexistence alters (b–d). Three potential mechanisms allow for coexistence beyond the parameter space defined by population-level predictions. Each carries a distinctive spatial and temporal signature (Velázquez et al. 2014).

Describing forests in three dimensions

The second major line of research, which feeds directly into the work above, is in developing new methods for characterising the three-dimensional structure of vegetation using terrestrial laser-scanning. This is mainly in collaboration with Martin Smith in the School of Engineering at Nottingham and Ting Yun at Nanjing Forestry University. This has also led to the development of a commercial product TreeSLAM in 2021 funded by CivTech and delivered by Carbomap.

Zhu Y., Li D., Fan J., Zhang H., Eichhorn M.P., Wang X and Yun T. (2023). A reinterpretation of the gap fraction of tree crowns from the perspectives of computer graphics and porous media theory. Frontiers in Plant Science 14:1109443. Open Access

Xue X., Jin S., An F., Zhang H., Fan J., Eichhorn M.P., Jin C., Chen B., Jiang L. and Yun T. (2022). Shortwave radiation calculation for forest plots using airborne LiDAR data and computer graphics. Plant Phenomics 2022, 9856739. pdf

Yun T., Jiang K., Li G., Eichhorn M.P., Fan J., Liu F., Chen B., An F. and Cao L. (2021). Individual tree crown segmentation from airborne LiDAR data using a novel Gaussian filter and energy function minimization-based approach.  Remote Sensing of Environment 256, 112307. pdf

Huang Z., Huang X., Fan J., Eichhorn M.P., An F., Chen B., Cao L., Zhu Z. and Yun T. (2020). Retrieval of Aerodynamic Parameters in Rubber Tree Forests Based on Computer Simulation and Terrestrial Laser Scanning. Remote Sensing 12(8), 1318. pdf and summary.

Yun T., Cao L., An F., Chen B., Xue L., Li W., Pincebourde S., Smith M.J.  and Eichhorn M.P. (2019). Simulation of multi-platform LiDAR for assessing total leaf area in tree crowns. Agricultural and Forest Meteorology, 266–277, 107610. pdf

Eichhorn M.P. , Ryding J., Smith M.J, Gill R.M.A , Siriwardena G.M. and Fuller R.J. (2017). Effects of deer on woodland structure revealed through terrestrial laser scanning. Journal of Applied Ecology 54, 1615–1626. pdf

Ryding J., Williams E., Smith M.J. and Eichhorn M.P. (2015). Assessing handheld mobile laser scanners for forest surveys. Remote Sensing 7, 1095–1111. pdf

Hand-held scanner in use by
Hand-held scanner in use by Emily Williams; photo credit Joe Ryding.

Forest structure and its influence on other species:

Included here is a large amount of work on agroforestry systems, which were the subject of my first post-doc and remain a long-term interest. This is mostly from a conservation perspective, trying to understand how traditional methods of farming with trees can be both sustainable and create habitats for other species. It also offers the opportunity for many collaborations with other researchers. The papers below cover birds, insects, frogs, vertebrate frugivores, herbaceous plants and even humans. I’m always open to new systems in which to study the implications of forest structure.

Gresham A., Healey J.R., Eichhorn M.P., Barton O., Smith A.R. and Shannon G. (2023). Horizontal viewsheds of large herbivores as a function of woodland structure. Ecology and Evolution 13, e106099. Open access.

Laurentino T.G., Baur J., Usui T. and Eichhorn M.P. (2019). Liana abundance and relationships to sapling and tree hosts in an East African primary forest. African Journal of Ecology 57, 130–136. Summary here.

Broome A.,  Fuller R.J.,  Bellamy P.E., Eichhorn M.P., Gill R.M.A., Harmer R., Kerr G., Siriwardena G.M. (2017). Implications of lowland broadleaved woodland management for the conservation of target bird species. Research Note – Forestry Commission 2017 No.028. pdf

Norfolk O., Eichhorn M.P. and Gilbert F.S. (2016). Flowering ground vegetation within orchards increases wild pollinator visitation rate and fruit set in almond. Insect Conservation and Diversity 9, 236–243. pdf

Moore J., Sittmongkol S., Campos-Arceiz A., Tok Sumpah and Eichhorn M.P. (2016) Fruit gardens enhance vertebrate diversity and biomass in a Southeast Asian rain forest. Biological Conservation 194, 132–138. pdf

Norfolk O., Eichhorn M.P. and Gilbert F.S. (2015). Contrasting patterns of turnover between plants, pollinators and their interactions. Diversity and Distributions 21, 405–415. pdf

Norfolk O., Power A., Eichhorn M.P. and Gilbert F. (2015). Migratory bird species benefit from agricultural gardens in arid South Sinai. Journal of Arid Environments 114, 110–115. pdf

Norfolk O., Eichhorn M.P. and Gilbert F. (2014). Culturally valuable minority crops provide a succession of floral resources for flower visitors in traditional orchard gardens. Biodiversity and Conservation 23, 3199–3217. pdf

Fuller R.J., Bellamy P.E., Broome A., Calladine J., Eichhorn M.P., Gill R.M. and Siriwardena G.M. (2014). Effects of woodland structure on woodland bird populations: An assessment of the effects of changes in woodland structure on bird populations as a result of woodland management practices and deer browsing. Defra Project WC0793. http://randd.defra.gov.uk

Adum G.B., Eichhorn M.P., Oduro W., Ofori-Boateng C. and Rödel M.-O. (2013). Two-stage recovery of amphibian assemblages following selective logging of tropical forest. Conservation Biology 27, 354–363. pdf

Norfolk O., Eichhorn M.P. and Gilbert F.S. (2013). Traditional agricultural gardens conserve wild plants and functional richness in arid South Sinai. Basic and Applied Ecology 14, 659-669. pdf

Eichhorn M.P., Ratliffe L.C. and Pollard K.M. (2011). Attraction of ants by an invasive Acacia. Insect Conservation and Diversity 4, 235–238. pdf

Eichhorn M.P., Compton S.G. and Hartley S.E. (2008). The influence of soil type on rain forest insect herbivore communities. Biotropica 40, 707–713. pdf

Vanwambeke S.O., Lambin E.F., Eichhorn M.P., Flasse S. P., Harbach R.E., Oskam L., Somboon P., van Beers S., van Benthem B.H.B., Walton C. and Butlin R.K. (2007). Impact of land-use change on dengue and malaria in Northern Thailand. Ecohealth 4, 37–51. pdf

Tok Sumpeh, Lah and Jon Moore setting up a camera trap. We have shown that fruit gardens established by forest-dwelling Chewong people increase the diversity and biomass of terrestrial frugivores in this forest (Moore et al. in press).
Tok Sumpeh, Lah and Jon Moore setting up a camera trap in Krau Wildlife Reserve, Malaysia. We have shown that fruit gardens established by forest-dwelling Chewong people increase the diversity and biomass of terrestrial frugivores in this forest (Moore et al. 2016). The interactions of Chewong with their forest environment form an ongoing research program.

Regeneration of tropical rain forests:

This was the subject of my PhD, many years ago, and which still continues as a sideline. I was initially looking at how insect herbivores might influence the growth of tropical tree seedlings. The short story is that they didn’t, at least not detectably. They did, however, influence later survival, but only long after my thesis was finished. We now have 15 years of continuous data. Publications looking at growth and survival of seedlings over this period are forthcoming.

Eichhorn M.P., Nilus R., Compton S.G., Hartley S.E. and Burslem D.F.R.P. (2010). Herbivory of tropical rain-forest tree seedlings correlates with future mortality. Ecology 91, 1092–1101. pdf

Eichhorn M.P., Fagan K.C, Dent D.H., Compton S.G. and Hartley S.E. (2007). Explaining leaf herbivory rates on tree seedlings in a Malaysian rain forest. Biotropica 39, 416–421. pdf

Eichhorn M.P., Compton S.G. and Hartley S.E. (2006). Seedling species determines rates of leaf herbivory in a Malaysian rain forest. Journal of Tropical Ecology 22, 513–519. pdf

seedling
We planted out these seedlings in Sepilok Forest Reserve, Sabah, back in 2000 and we’ve been following them ever since. Most are now dead but those that survive are much larger. Photo credit: Jake Snaddon.

Kamchatka:

After my most recent expedition to Kamchatka in 2008 I returned with an incredible quantity of data, along with herbarium specimens and a large box of soil samples. A couple of the Kamchatkan papers are featured above in the spatial organisation section, but there’s plenty more to come. Most of these will be relatively minor contributions but since so few people work on the peninsula I’m determined to get more information about it into the literature. I’m also plotting a grant proposal and a likely return.

This paper is a ‘data dump’ which exists largely so that I can cite it, but also gives a general introduction to the wonderful forests found there:

Eichhorn M.P. (2010). Boreal forests of Kamchatka: Structure and composition. Forests 1,
154–176. pdf

Look at it. How could anyone fail to fall in love with such a place? Apart from the biting insects, roving bears and occasional heavily-armed Russians that is.
Look at it. How could anyone fail to fall in love with such a place? Apart from the biting insects, roving bears and occasional heavily-armed Russians that is.

Decolonisation

What does a white European have to say about decolonisation? It is the responsibility of those of us with platforms to draw attention to the issues and actively move towards decolonising our research practices. This is something we should act upon because it is ethically necessary rather than waiting until someone tells us to do so.

Eichhorn M.P., Baker K., and Griffiths M. (2020). Steps towards decolonising biogeography. Frontiers of Biogeography 12, e44795. This paper resulted in a comment, charmingly titled Glass Houses, to which we responded with a call to Smash the Windows.

Baker K., Eichhorn M.P. and Griffiths M. (2019). Decolonizing field ecology. Biotropica 51, 288–292. pdf

Is that you as well?

Although there are several major streams to my research, I’ve been involved in a number of other projects that are difficult to slot into the pigeon-holes above. Some of these might end up being developed further, others are just indicators of past academic lives. I doubt that I’ll ever work on snail behaviour again. Agroforestry policy is still in scope: see the string of papers with my brilliant former PhD student Olivia Norfolk above. I also have several papers still to write on conservation of Lundy cabbage, which might eventually get its own section, but right now it’s on the back-burner. Some of these oddities have ended up among my most-cited papers.

Price D.M., Lim A., Callaway A., Eichhorn M.P., Wheeler A.J., Lo Iacono C. and Huvenne V.A.I. (2021). Fine-scale heterogeneity of a cold-water coral reef and its influence on the distribution of associated taxa. Frontiers in Marine Science 8, 556313. pdf

Wilson H.L., Johnson M.F., Wood P.J., Thorne C.R., Eichhorn M.P. (2021). Anthropogenic litter is a novel habitat for aquatic macroinvertebrates in urban rivers. Freshwater Biology 66, 524–534.

Norfolk O., Gilbert F. S., and Eichhorn M.P. (2018). Alien honeybees increase pollination risks for range-restricted plants. Diversity and Distributions, 24, 705–713. pdf

Pliego Pliego E., Velázquez-Castro J., Eichhorn M.P., and Fraguela Collar A. (2018). Increased efficiency in the second-hand tire trade provides opportunity for dengue control. Journal of Theoretical Biology 437, 126–136. pdf

Davison A., Frend H.T., Moray C., Wheatley H., Searle L.J and Eichhorn M.P. (2009). Mating behaviour in Lymnaea stagnalis pond snails is a maternally inherited, lateralized trait. Biology Letters 5, 20–22. pdf

Simensen S.M. and Eichhorn M.P. (2012). Assessment of the threat of herbivory by rabbits, sika deer and feral goats to Lundy Cabbage (Coincya wrightii) through faecal analysis. Journal of the Lundy Field Society 3, 25–32. pdf

Tripp E.J., Crittenden P.D. and Eichhorn M.P. (2012) Plant diversity of a lowland heathland site on Lundy. Journal of the Lundy Field Society 3, 33–40. pdf

Eichhorn M.P., Paris P., Herzog F., Incoll L.D., Liagre F., Mantzanas K., Mayus M., Moreno
G., Papanastasis V.P., Pilbeam D.J., Pisanelli A. and Dupraz C. (2006). Silvoarable systems in Europe: Past, present and future prospects. Agroforestry Systems 67, 29–50. pdf

These dehesa landscapes in central Spain aren't just beautiful; they're of major conservation importance and a traditional system of agroforestry that has been in place for thousands of years. Photo credit: Gerardo Moreno.
These dehesa landscapes in central Spain aren’t just beautiful; they’re of major conservation importance and a traditional system of agroforestry that has been in place for thousands of years. Photo credit: Gerardo Moreno.

* My chances of a research sabbatical are about as high as those of discovering a lost population of dragons. Unless you’re reading this, in charge of a large institutional budget, and would like to invite me. In which case HELLO! HELLO! I’M WAVING AT YOU!