Detecting the presence, and impact, of peoples past impact in ecosystems and landscapes in the tropics is a challenging because the traces that they leave behind are few and disentangling them from ‘natural’ (non-human related) variability is a challenge. As an Associate Editor for Vegetation History & Archaeobotany (VHAA) I enjoy handling manuscripts that think about these issues and explore the role of humans in tropical landscapes. Two recent papers published in VHAA touched on this subject (one of which I “communicated” as an editor).
Bodin et al. (2020) studied charcoal recovered from soil at sites with a gradient of archaeological evidence for past human activity in French Guiana.
Goethals & Verschuren (2019) explored the relationship between the amount of dung fungi found in lake sediments and the herbivore populations living around the lakes.
The next two days were spent in motorized dugouts sitting on our gear bags, with tarps pulled over us. Every now and then the driving rain would relent and we would see macaws and toucans flying across the Aguarico River. We stayed one night in a village that had been abandoned due to recent floods, another with Siona hunters who were preparing their blow darts (for monkeys). There were very few houses along the river and we hardly saw another boat in three days. Then we arrived, well almost. We had turned off the main channel onto the tiny Zancudo river. Little used, this stream was a jumble of fallen trees that the Siona chopped their way through. A large tree just beneath the surface posed a problem that was solved by stripping the bark from Cecropiatrees and laying it inside surface facing up, backing up, revving the engine, and aiming straight for the bark. The slick insides of the Cecropiaallowed the canoes to shoot the trunk and on we went. Then we reached the marsh. When I say ‘marsh’ it was a forest of Montricardia arborescens. This is an aquatic Aroid that grows about 3 m high. The trunks are about 3-5 cm in diameter and is THE favored hangout for caiman and anaconda (I have since learned). No Siona in their right mind gets out of a boat in such a marsh and so we were stuck……so close but yet so far. Our only chance of getting through the marsh was to hop out of the boats and pull them through.
The author pulling a canoe through the marsh at Zancudococha in 1988. Photo: Miriam Steinitz-Kannan.
We had two boats and so the most dispensable members of the team, Paulo de Oliveira and I, were given the job of hauling the boats. A couple of happy hours later we were through the marsh and onto the lake.
Our first jobs were to find somewhere dry enough to camp, unload, set up camp, and survey the lake. Paul Colinvaux the team leader always launched an inflatable and surveyed the lake on first arrival. Meanwhile the rest of us set up camp. About 20 minutes into all this activity there was the unmistakable crack of a shotgun. In a few more minutes the Chief’s sons emerged from the forest with the news that they had shot a large tapir. The tapir fed the group for the next few days, but I ate tuna and a sausage that had turned blue and slimy, unable to reconcile my role in, what to me, was an unfortunate outcome of our petitioning the Siona to bring us to their sacred lake. The coring was more successful than at Cuyabeno in that we recovered 5m of sediment, but it was clearly a young system and wouldn’t answer our research question. This expedition was a disappointment scientifically, but an incredible snapshot along the gradient of Amazonian development.
View from our campsite of an island in Lake Zancudococha (1988). Photo: M. Bush.
The 1988 camp at Zanucudococha was a place of field biology. Chemist Mike Miller worked late into the night on limnology, while field microscopes were used to get an early glimpse of plankton and diatoms. From left to right: Melanie Riedinger-Whitmore, Eduardo Asanza, Haki, Paulo de Oliveira and Paul Colinvaux. Photo: M. Bush.
There is a 18 month post-doctoral research position within the Department of Theoretical & Computational Ecology at IBED focused on Global Ecology, we are looking for someone with skills and experience the following areas:
PhD in ecology, biodiversity or a related discipline
quantitative skills and statistical analyses
species distribution modelling
analyses of species composition, functional traits and species interactions
The paper we discussed was “Columbus’ footprint in Hispaniola: A paleoenvironmental record of indigenous and colonial impacts on the landscape of the central Cibao Valley, northern Dominican Republic” by Castilla-Beltrán et al (2018). The paper provides a multi-proxy paleoecological reconstruction of the Caribbean island nation of the Dominican Republic, spanning the last 1100 years. Personally I found this to be a very interesting paper, packed with information and interpretations on the impact of anthropogenic factors on past Caribbean environments. What this paper nicely demonstrates is the difference in impact between pre-colonial and post-colonial societies on the vegetation of the Dominican republic. Pre-colonial Hispaniola was inhabited by indigenous societies, the Taíno people, and while this paper clearly shows them having had an environmental impact in the form of fire management (e.g. for slash and burn agriculture), small scale deforestation and the introduction of cultivars such as maize and squash, their environmental impact remains modest compared to post-colonial disturbances. Columbus arriving in AD 1492 signified a moment of change in the landscape. The paleorecord suggests that, after an initial collapse of the Taíno population, the colonization of the Dominican Republic by the Spanish brought with it deforestation, crop monoculture and the introduction of European livestock, all of which still characterizes the landscape to this day.
The discussion mainly focused on the chronology used. One of the radiocarbon samples was excluded from the age-depth model for no apparent reason, which led us to discuss the importance of critically evaluating your calibrated radiocarbon dates and which ones to incorporate in your age-depth model. The age-depth model currently used implied a shift in pollen composition c. 30 years before the arrival of the Spanish. We were unsure how to interpret these findings because you would expect the shift to happen afterwards, so my initial thought was that it had to be a fault in the chronology. This chronology however does imply a large charcoal peak followed by a rapid decline that coincides precisely with the arrival of the Spanish, and it turned out that this was the reason the authors settled on this chronology.
Even though this paper by Castilla-Beltrán et al. didn’t spark any heated discussions, its incorporation of ecology, botany, history, archeology and geology still showcases the interdisciplinary nature of paleoecology, something I very much enjoy about this field of research.
I recently joined the editorial board of Plant Ecology & Diversity at the invitation of editor-in-chief Laszlo Nagy (University of Campinas, Brazil). The journal focuses on ecological and evolutionary issues within plant biology with broad themes covering biodiversity, conservation and global change. Furthermore, I think this is a particularly interesting journal to be involved with because of its option for double-blind peer reviews, commitment to providing a platform for ‘negative results’ and ‘repeat experiments’, and its open access Grubb Review series (Nagy & Resco de Dios, 2016); which already includes many significant articles, including: Ashton (2017), Barbeta & Peñuelas (2016), Grubb (2016), Körner (2018), Valladares et al. (2016), and Wilkinson & Sherratt (2016). In addition to the invited Grubb Reviews the journal publishes: research articles, short communications, reviews, and scientific correspondence. My role on the editorial board will be to cover submissions related to tropical palaeoecology and biogeography. So please consider submitting to Plant Ecology & Diversity if you have some exciting new research or ideas that you think would be appropriate.
The Netherlands Annual Ecology Meeting (NAEM) 2019 takes place in the 12 and 13 February. This annual showcase of predominantly Dutch based ecological research will take place, as usual, at Conference Centre “De Werelt” (Lunteren). I am particularly excited this year as, along with Marielos Pena Carlos and Patrick Jansen, I am co-convening a session on “Tropical Ecology”. The first time I have contributed to the program in this way. Our session will be on the second day of the conference and contain the following exciting presentations:
15:00 Predator avoidance and prey tracking in a Neotropical forest (Constant Swinkels, Wageningen University & Research)
15:20 The role of fig volatiles in pollinator specificity and fig diversity (Aafke Oldenbeuving, Naturalis Biodiversity Center)
15:40 Mangrove Atlantis: Can mangroves keep up with extreme land-subsidence? (Celine van Bijsterveldt, Royal Netherlands Institute for Sea Research)
16:00 Break
16:10 The fate of forests in agro-forest frontier landscapes, implications for conservation (Madelon Lohbeck, Wageningen University & Research)
16:30 Trends in the variability of Specific Leaf Area of paramo vegetation during succession (Marian Cabrera, University of Amsterdam)
16:50 Succession dynamics of tree and soil fungal communities in regenerating tropical rainforests are strongly influenced by regional species pool and abiotic factors (Irene Adamo, Naturalis Biodiversity Center)
The 2018 edition of the University of Amsterdam masters course “Environments Through Time” is now up and running. The course sits at the interface between ecology, physical geography and archaeology and seeks to provide students with a better understanding of how long-term (>100’s years) datasets can provide insights in to past environmental change.
In the first week of the course the students had to present their ‘favourite’ paper in just three (3) minutes! Quite a challenge and lots of fun. This years selection of papers themed around:
mega-fauna extinctions (Bakker et al., 2016; Gill et al., 2009; van der Kaars et al., 2017),
impacts of human land use practices (Bitusik et al., 2018; Carson et al., 2014; Chepstow-Lusty et al., 2009; Gauthier et al., 2010; Tisdall et al., 2018), and
climatic drivers of vegetation change (Haug et al., 2001; Tierney et al., 2017; Tudhope et al., 2001).
For full list of papers presented see below.
In the second and third weeks (now ongoing) students get to deconstruct published chronologies and conduct time series analsis of multi-proxy datasets. Data for these excercises is frequently is extracted from databases such as Neotoma, Pangea, NOAA – paleoclimatology datasets database and the Global Charcoal Database – which shows the importance of these open access databases for developing effective research led eductation, as well as pushing forward to frontiers of research.