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Pollen-based vegetation, biodiversity, and biome reconstructions over the last 15,500 years from sediment core data at Mbi Crater in the Cameroon highlands (6.089273° N, 10.348549° E; 2015 m above sea level) are used to discuss the behavior of the lower edge of the Afromontane forest facing climate change. The data reveal that the post-glacial forest change gradually happened at Mbi and that the forest-wooded grassland ecotone was highly influenced by the climate variability related to the North Atlantic. The forest disruption and diversity loss intermittently occurred over the whole period, and their vegetation changes temporally match dry-cold events at the northern latitudes during the Younger Dryas, at 9.5–9.1 ka, 8.6–8.0 ka, 6.7–6.0 ka, 3.2 ka, and during the Little Ice Age (LIA). During the LIA, the mountain forest was subject to unprecedented levels of disturbance at all altitudes, unlike the seasonal lowland forests, which appears to have been only marginally affected.

The carbon (C) dynamics of northern peatlands are sensitive to hydrological changes owing to ecohydrological feedbacks. We quantified and evaluated the impact of water level variations in a beaver pond (BP) on the CO2 flux dynamics of an adjacent, raised Sphagnum–shrub-dominated bog in southern Canada. We applied the CoupModel to the Mer Bleue bog, where the hydrological, energy and CO2 fluxes have been measured continuously for over 20 years. The lateral flow of water from the bog to the BP was estimated by the hydraulic gradient between the peatland and the BP's water level and the vertical profile of peat hydraulic conductivity. The model outputs were compared with the measured hydrological components, CO2 flux and energy flux data (1998–2019). CoupModel was able to reproduce the measured data well. The simulation shows that variation in the BP water level (naturally occurring or due to management) influenced the bog net ecosystem exchange (NEE) of CO2. Over 1998–2004, the BP water level was 0.75 to 1.0 m lower than during 2017–2019. Simulated net CO2 uptake was 55 gCm-2yr-1 lower during 1998–2004 compared to 2017–2019 when there was no BP disturbance, which was similar to the differences in measured NEE between those periods. Peatland annual NEE was well correlated with water table depth (WTD) within the bog, and NEE also shows a linear relation with the water level at the BP, with a slope of −120 gCO2-Cm-2yr-1m-1. The current modelling predicts that the bog may switch from CO2 sink to source when the BP water levels drop lower than ∼ 1.7 m below the peat surface at the eddy covariance (EC) tower, located on the bog surface 250 m from the BP. This study highlights the importance of natural and human disturbances to adjacent water bodies in regulating the net CO2 uptake function of northern peatlands.

The vicinity of the Rozprza archaeological site (central Poland) has been the area of a series of palaeoecological studies tracking the environmental history of the Luciąża River valley up to ca. 13,200 cal. BP. Numerous subfossil palaeomeanders of different sizes have been discovered in the valley floor. Here, we present the first results of multiproxy research on the paleo-oxbow lake fill, one of the oldest in the region. The wide range of palaeoecological analyses resulted in reconstructions of vegetation history, climatic, hydrological and habitat changes. The studied oxbow was an aquatic ecosystem with diverse invertebrate fauna until the end of Younger Dryas when it transformed into a limno-telmatic habitat. The sediment composition indicates active denudation processes and several episodes of turbulent hydrological conditions. Such an increased river activity could have caused flooding, resulting in an allochthonous matter supply to the oxbow lake in Late Vistulian. Environmental changes were strictly related to the regional features of the catchment, the transformation of soils, and the hydrogeological conditions. The chironomid- and pollen-inferred climatic reconstructions indicate periods of high and low continentality. The chironomid record indicates relatively cool summer conditions in the Allerød, especially ca. 13,000 cal. BP, possibly related to the Gerzensee Oscillation. On the other hand, a distinct increase of summer temperatures in Younger Dryas (up to 16 °C) was recorded. Such a situation was also confirmed in some other studies from the region, suggesting that it might be the effect of some specific, local palaeoclimatic conditions. Fundator badań: Fundator badań: Optional.empty

International audience; The root system of a plant is composed of the primary, lateral and adventitious roots (ARs). Lateral roots always develop from roots, whereas ARs form from stem or leaf‐derived cells. AR formation is part of the normal development of the plant and occurs naturally, like in most monocotyledonous for which they constitute the main root system or in many dicotyledonous species that propagate vegetatively. Adventitious rooting is an essential step for vegetative propagation of economically important horticultural and woody species as it allows clonal propagation and rapid fixation of superior genotypes prior to their introduction into production or breeding programmes. Development of ARs is a complex process that is affected by multiple endogenous and environmental factors, including phytohormones; light; nutritional status; associated stress responses, such as wounding; and genetic characteristics.

Aquaponics, one of the vertical farming methods, is a combination of aquaculture and hydroponics. To enhance the production capabilities of the aquaponics system and maximize crop yield on a commercial level, integration of Industry 4.0 technologies is needed. Industry 4.0 is a strategic initiative characterized by the fusion of emerging technologies such as big data and analytics, internet of things, robotics, cloud computing, and artificial intelligence. The realization of aquaponics 4.0, however, requires an efficient flow and integration of data due to the presence of complex biological processes. A key challenge in this essence is to deal with the semantic heterogeneity of multiple data resources. An ontology that is regarded as one of the normative tools solves the semantic interoperation problem by describing, extracting, and sharing the domains’ knowledge. In the field of agriculture, several ontologies are developed for the soil-based farming methods, but so far, no attempt has been made to represent the knowledge of the aquaponics 4.0 system in the form of an ontology model. Therefore, this study proposes a unified ontology model, AquaONT, to represent and store the essential knowledge of an aquaponics 4.0 system. This ontology provides a mechanism for sharing and reusing the aquaponics 4.0 system’s knowledge to solve the semantic interoperation problem. AquaONT is built from indoor vertical farming terminologies and is validated and implemented by considering experimental test cases related to environmental parameters, design configuration, and product quality. The proposed ontology model will help vertical farm practitioners with more transparent decision-making regarding crop production, product quality, and facility layout of the aquaponics farm. For future work, a decision support system will be developed using this ontology model and artificial intelligence techniques for autonomous data-driven decisions.

The considerable intensification of human activity in the second and first centuries BC in Central Europe was related to the sudden appearance of a network of large fortified towns, which are known as oppida. Bibracte was one of the most important oppida in France, but knowledge about the evolution of its hinterland is still incomplete. This article addresses the evolution of the landscape surrounding this oppidum. Our research was based on a study of sedimentary profiles sampled around the archaeological site and examined by physical, geochemical and palaeoecological analyses. Sediment sequences indicate that the earliest human-induced erosion associated with geomorphological change occurred in the 4th–1st century BC. Geochemical results indicate ancient mining and metallurgy in the catchment during the same time. Palaeoecological proxies from the same period point to a mosaic of an open cultural landscape with locally suppressed forest vegetation and prevailing pastoralism. Anthropogenic impact resurged in the 11th–13th centuries AD and was associated with livestock grazing and rye (Secale cereale) cultivation. Thereafter, the reconstructed human impact from the 15th century AD onwards was probably related to forest management focused on timber floating as well as to the cultivation of chestnut (Castanea sativa) and hemp (Cannabis sativa).

The Azraq oasis in the Eastern Desert of Jordan has produced considerable stone artefacts attributed to the early Palaeolithic, yet relatively few data are available regarding the chronology and palaeoenvironmental contexts of the remains. In this study, we present stratigraphic, sedimentological, and micropalaeontological analyses of the Late Acheulean site SM1 located within the former Shishan Marsh, which we combine with geochronological and sedimentological data from 13 neighbouring geological exposures to reconstruct landscape evolution at the western margin of the Shishan Marsh. We then discuss the Late Quaternary palaeolandscapes of the Greater Azraq Oasis Area over the past c. 350 ka. Our work demonstrates that the central Azraq Basin experienced three local wetting-drying cycles since the late Middle Pleistocene that would have dramatically shifted the quantity and distribution of freshwater resources, ranging from expansive wetland landscapes to desert refugia characterised by isolated spring pools—changes that would have significantly impacted the mobility decisions and settlement patterns of Palaeolithic inhabitants. Our study highlights that developing long-term records of human-environment dynamics in arid environments requires a mosaic approach to palaeoenvironmental reconstruction that is nested within a well-developed understanding of landscape evolution.

Climate change is expected to have detrimental consequences on fragile ecosystems, threatening biodiversity, as well as food security of millions of people. Trees are likely to play a central role in mitigating these impacts. The microclimatic conditions below tree canopies usually differ substantially from the ambient macroclimate as vegetation can buffer temperature changes and variability. Trees cool down their surroundings through several biophysical mechanisms, and the cooling benefits occur also with trees outside forest. The aim of this study was to examine the effect of canopy cover on microclimate in an intensively modified Afromontane landscape in Taita Taveta, Kenya. We studied temperatures recorded by 19 microclimate sensors under different canopy covers, as well as land surface temperature (LST) estimated by Landsat 8 thermal infrared sensor. We combined the temperature records with high-resolution airborne laser scanning data to untangle the combined effects of topography and canopy cover on microclimate. We developed four multivariate regression models to study the joint impacts of topography and canopy cover on LST. The results showed a negative linear relationship between canopy cover percentage and daytime mean (R2=0.65) and maximum (R2=0.75) temperatures. Any increase in canopy cover contributed to reducing temperatures. The average difference between 0 % and 100 % canopy cover sites was 5.2 ∘C in mean temperatures and 10.2 ∘C in maximum temperatures. Canopy cover (CC) reduced LST on average by 0.05 ∘C per percent CC. The influence of canopy cover on microclimate was shown to vary strongly with elevation and ambient temperatures. These results demonstrate that trees have a substantial effect on microclimate, but the effect is dependent on macroclimate, highlighting the importance of maintaining tree cover particularly in warmer conditions. Hence, we demonstrate that trees outside forests can increase climate change resilience in fragmented landscapes, having strong potential for regulating regional and local temperatures.

We review palaeoenvironmental proxies and combinations of these relevant for understanding hunter-gatherer niche construction activities in pre-agricultural Europe. Our approach consists of two steps: (1) identify the possible range of hunter-gatherer impacts on landscapes based on ethnographic studies; (2) evaluate proxies possibly reflecting these impacts for both the Eemian (Last Interglacial, Middle Palaeolithic) and the Early–Middle Holocene (Mesolithic). We found these paleoenvironmental proxies were not able to unequivocally establish clear-cut differences between specific anthropogenic, climatic and megafaunal impacts for either time period in this area. We discuss case studies for both periods and show that published evidence for Mesolithic manipulation of landscapes is based on the interpretation of comparable data as available for the Last Interglacial. If one applies the ‘Mesolithic’ interpretation schemes to the Neanderthal record, three common niche construction activities can be hypothesised: vegetation burning, plant manipulation and impact on animal species presence and abundance. Our review suggests that as strong a case can be made for a Neanderthal impact on landscapes as for anthropogenic landscape changes during the Mesolithic, even though the Neanderthal evidence comes from only one high-resolution site complex. Further research should include attempts (e.g. by means of modelling studies) to establish whether hunter-gatherer impact on landscapes played out at a local level only versus at a larger scale during both time periods, while we also need to obtain comparative data on the population sizes of Last Interglacial and Holocene hunter-gatherers, as these are usually inferred to have differed significantly.

Fisheries discards have become a source of concern for the perennation of marine resources. To reduce discards, the European Union adopted a Landing Obligation under the reform of its Common Fisheries Policy. However, food web consequences of reducing discards remain uncertain since their degree and pathway of reintegration are understudied. We used multi-marker DNA metabarcoding of gut contents and an ecological network approach to quantify marine fauna reliance on discarded fish and functional importance of discard consumers in coastal fishing grounds. We show that potential discard consumption is widespread across fish and invertebrates, but particularly important for decapods, which were also pinpointed as functionally important. Potential discard consumption may represent up to 66% of all interactions involving fish prey in the reconstructed network. We highlight that discard reliance may be more important than previously assessed in some fishing areas and support functionally important taxa. While reducing discarding remains a conservation priority, it is crucial to understand discards reintegration in marine food webs to anticipate changes in the context of an ecosystem approach to fisheries management.

The eddy-covariance technique measures carbon, water, and energy fluxes between the land surface and the atmosphere at hundreds of sites globally. Collections of standardised and homogenised flux estimates such as the LaThuile, Fluxnet2015, National Ecological Observatory Network (NEON), Integrated Carbon Observation System (ICOS), AsiaFlux, AmeriFlux, and Terrestrial Ecosystem Research Network (TERN)/OzFlux data sets are invaluable to study land surface processes and vegetation functioning at the ecosystem scale. Space-borne measurements give complementary information on the state of the land surface in the surroundings of the towers. They aid the interpretation of the fluxes and support the benchmarking of terrestrial biosphere models. However, insufficient quality and frequent and/or long gaps are recurrent problems in applying the remotely sensed data and may considerably affect the scientific conclusions. Here, we describe a standardised procedure to extract, quality filter, and gap-fill Earth observation data from the MODIS instruments and the Landsat satellites. The methods consistently process surface reflectance in individual spectral bands, derived vegetation indices, and land surface temperature. A geometrical correction estimates the magnitude of land surface temperature as if seen from nadir or 40∘ off-nadir. Finally, we offer the community living data sets of pre-processed Earth observation data, where version 1.0 features the MCD43A4/A2 and MxD11A1 MODIS products and Landsat Collection 1 Tier 1 and Tier 2 products in a radius of 2 km around 338 flux sites. The data sets we provide can widely facilitate the integration of activities in the eddy-covariance, remote sensing, and modelling fields.

Type 2 diabetes mellitus (T2DM) disproportionately affects Indigenous populations. It is possible that exposure to complex mixtures of environmental contaminants contribute to T2DM development. This study examined the association between complex environmental contaminant mixtures and T2DM among Canadian Indigenous communities from the Eeyou Istchee territory, Quebec, Canada. Using data from the cross-sectional Multi-Community Environment-and-Health Study (2005–2009) Principal Component Analysis (PCA) was used to reduce the dimensionality of the following contaminants: 9-polychlorinated biphenyl congeners; 7-organic pesticides; and 4-metal/metalloids. Following this data reduction technique, we estimated T2DM prevalence ratios (PR) and 95% confidence intervals using modified Poisson regression with robust error variance across derived principal components, adjusting for a priori covariates. For both First Nation adult males (n = 303) and females (n = 419), factor loadings showed dichlorodiphenyltrichloroethane (DDT) and lead (Pb) highly loaded on the second principal component (PC) axis: DDT negatively loaded, and Pb positively loaded. T2DM was significantly associated with PC-2 across all adjusted models. Because PCA produces orthogonal axes, increasing PC-2 scores in the fully adjusted model for females and males showed (PR = 0.84; 95% CI 0.72, 0.98) and (PR = 0.78; 95% CI 0.62, 0.98), respectively. This cross-sectional study suggests that our observed association with T2DM is the result of DDT, and less likely the result of Pb exposure. Further, detectable levels of DDT among individuals may possibly contribute to disease etiology.

International audience; Lake Bottom oxbow is a partially-filled oxbow lake within an alluvium filled sandstone canyon reach of the Dolores River in eastern Utah, USA. Two adjacent sediment cores were obtained from the Lake Bottom oxbow to better understand the depositional and environmental history of the site and region. Depositional ages were determined using radiocarbon dating (14C) of pollen extracts, optically stimulated luminescence (OSL) of sand, concentration of 137Cs and 210Pb radioisotopes, and the first occurrence of pollen from human-introduced crops (Zea mays) and trees and shrubs (Tamarix) found in the oxbow sediments. Age control from OSL, short-lived radioisotopes, and pollen are stratigraphically consistent and fit the geomorphic character of the partially-filled oxbow, which suggests it is a late Holocene feature. In contrast, the 14C results appear to be contaminated by old carbon and produced age overestimates of 3000–12,000 years. Our findings suggest that multiple dating methods should be employed when applying radiocarbon dating to settings that are susceptible to contamination by recycled old carbon, especially when dating pollen extracts that are difficult to determine organic purity. The OSL results suggest initial oxbow formation by 860 ± 270 yr (±2σ) and then rapidly infilled with fluvial sediment. The OSL age control indicates the oxbow formed during the Medieval Climate Anomaly, a time of enhanced summer moisture and active flooding in the Dolores River watershed. Similar low-elevation records in the arid Colorado Plateau are rare, making this site an important contribution to the regional paleoenvironmental record.

Since the early twentieth century, the copper-mining industry on the Zambian and Congolese Copperbelt has moved millions of tonnes of earth and dramatically reshaped the landscape. Nonetheless, mining companies, governments and even residents largely overlooked the adverse environmental aspects of mining until the early 1990s. By scrutinising environmental knowledge production on the Central African Copperbelt from the 1950s until the late 1990s, particularly regarding notions of 'waste', this article problematises the silencing of the environmental impacts of mining. To make the environmental history of the Copperbelt visible, this article examines forestry policies, medical services and environmental protests. Moreover, by historically tracing the emergence of environmental consciousness, it contextualises the sudden 'discovery' of pollution in the 1990s as a local and (inter)national phenomenon. Drawing on rare archival and oral history sources, it provides one of the first cross-border environmental histories of the Central African Copperbelt.

Phosphate is an essential macronutrient for fungal proliferation as well as a key mediator of antagonistic, beneficial, and pathogenic interactions between fungi and other organisms. In this review, we summarize recent insights into the integration of phosphate metabolism with mechanisms of fungal adaptation that support growth and survival. In particular, we highlight aspects of phosphate sensing important for responses to stress and regulation of cell-surface changes with an impact on fungal pathogenesis, host immune responses, and disease outcomes. Additionally, new studies provide insights into the influence of phosphate availability on cooperative or antagonistic interactions between fungi and other microbes, the associations of mycorrhizal and endophytic fungi with plants, and connections with plant immunity. Overall, phosphate homeostasis is emerging as an integral part of fungal metabolism and communication to support diverse lifestyles.

Tracheid length and width patterns from pith to bark at a height of 0.6 m in uneven-aged Norway spruce (Picea abies L. (H.) Karst) trees were addressed. The identification of the main factors and a comparison with even-aged stands were also pursued. 96 trees were sampled from experimental stands in Southern Finland. The material encompassed the variation in tracheid properties from early years to silvicultural maturity, i.e. from corewood to outerwood up to a cambial age of 111 years. Data from 39 Norway spruce trees from even-aged stands we utilized for comparison. Models fitted to the data indicated that annual ring widths did not influence mean tracheid dimensions but the latewood proportion showed a significant influence on tracheid dimensions. Tracheids in uneven-aged stands were slightly wider and longer at the base of the stem with a similar tree diameter, cambial age, and annual ring number. Tracheid length and width patterns from pith to bark at a height of 0.6 m in uneven-aged Norway spruce (Picea abies (L.) Karst.) trees were studied. Identification of the main factors and a comparison with even-aged stands were also carried out. Ninety-six trees were sampled from experimental stands in southern Finland. The material encompassed the variation in tracheid properties from early years to silvicultural maturity, i.e., from corewood to outerwood up to a cambial age of 111 years. Data from 39 Norway spruce trees from even-aged stands were utilized for comparison. Models fitted to the data indicated that annual ring widths did not influence mean tracheid dimensions but that the latewood proportion had a significant influence on tracheid dimensions. Tracheids in uneven-aged stands were slightly wider and longer at the base of the stem in trees with a similar diameter, cambial age, and annual ring number.

The study of primate social behavior in the wild has emerged as a tool with great potential for increasing our understanding early hominins. However, the application of models generated from observation of living primates to the archaeological record is challenging. Bestwood 1, a component of the Kathu Complex of sites in the Northern Cape Province, South Africa provides an opportunity to consider the spatial organization of hominin activity across a landscape at ca. 360 kyr in an archaeological context attributed to the Fauresmith. This article provides the first data for the spatial distribution of artifacts at Bestwood 1 and argues in favor of a baboon model of social organization for the hominin groups that generated the spatial patterning found at this locality.

Funding: Floristic identification in plots in the RAINFOR forest monitoring network have been supported by the Natural Environment Research Council (grants NE/B503384/1, NE/ D01025X/1, NE/I02982X/1, NE/F005806/1, NE/D005590/1 and NE/I028122/1) and the Gordon and Betty Moore Foundation. In a time of rapid global change, the question of what determines patterns in species abundance distribution remains a priority for understanding the complex dynamics of ecosystems. The constrained maximization of information entropy provides a framework for the understanding of such complex systems dynamics by a quantitative analysis of important constraints via predictions using least biased probability distributions. We apply it to over two thousand hectares of Amazonian tree inventories across seven forest types and thirteen functional traits, representing major global axes of plant strategies. Results show that constraints formed by regional relative abundances of genera explain eight times more of local relative abundances than constraints based on directional selection for specific functional traits, although the latter does show clear signals of environmental dependency. These results provide a quantitative insight by inference from large-scale data using cross-disciplinary methods, furthering our understanding of ecological dynamics. Publisher PDF

International audience; Monte Torretta (Pietragalla, PZ) represents one of the most interesting and less known settlements of ancient Lucania. The site was investigated in the last 50 years by several archaeological activities, but no result has been published so far. In order to study and disseminate the archaeological value of the site, the Université Paris 1 Panthéon‐Sorbonne and the Humboldt‐Universität zu Berlin has established the joint Pietragalla Project. The project is based on a multidisciplinary approach, which aims at studying the settlement and at recovering the lost information obtained by the previous archaeological works. The first geophysical activities conducted on the site offer important results, which increase the knowledge of the site and will help the archaeologists in their future investigation. Through the comparison and integration of different geophysical methodologies, including ground penetrating radar, electrical resistivity tomography and geomagnetic measurements, various information was obtained in proximity of the fortification walls and the two main gates of the site. Moreover, geological and geomorphological interpretations highlighted important information on the archaeological site. The obtained results show the importance of geophysical activities in a context strongly damaged by rural activities of the last century. From an archaeological point of view, the geophysical surveys conducted in 2017 and 2018 show a dense building activity within the area enclosed by the walls. Thanks to these results, we are now able to understand the settlement pattern in the longue durée, at the least for the western part of the infra‐muros area.

As top predators, seabirds can be indirectly impacted by climate variability and commercial fishing activities through changes in marine communities. However, high mobility and foraging behaviour enables seabirds to exploit prey distributed patchily in time and space. This capacity to adapt to environmental change can be described through the study of their diet. Traditionally, the diet of seabirds is assessed through the morphological identification of prey remains in regurgitates. This sampling method is invasive for the bird and limited in terms of taxonomic resolution. However, the recent progress in DNA-based approaches is now providing a non-invasive means to more comprehensively and accurately characterize animal diets. Here, we used a non-invasive metabarcoding approach to characterize the diet of the Westland petrel (Procellaria westlandica), which is an endangered burrowing species, endemic to the South Island of New Zealand. We collected 99 fresh faecal samples at two different seasons and in two different sub-colonies. Our aims were to describe the diet of the Westland petrel, investigate seasonal and spatial variation in the petrels’ diet, and assess potential impacts of the New Zealand fishery industry. We found that amphipods were the most common prey, followed by cephalopods and fish. Our results could be the result of natural foraging behaviour, but also suggest a close link between the composition of prey items and New Zealand’s commercial fishing activities. In particular, the high abundance of amphipods could be the result of Westland petrels feeding on discarded fisheries waste (fish guts). Our results also showed significant differences in diet between seasons (before hatching vs chick-rearing season) and between sampling sites (two sub-colonies 1.5 km apart), indicating plasticity in the foraging strategy of the Westland petrel. Due to its non-invasive nature, metabarcoding of faecal samples can be applied to large numbers of samples to help describe dietary variation in seabirds and indicate their ecological requirements. In our example, dietary DNA (dDNA) provided valuable information regarding the dietary preferences of an iconic species in New Zealand’s unique biodiversity. dDNA can thus inform the conservation of endangered or at-risk species that have elusive foraging behaviours.

International audience; Plant scientists and farmers are facing major challenges in providing food and nutritional security for a growing population, while preserving natural resources and biodiversity. Moreover, this should be done while adapting agriculture to climate change and by reducing its carbon footprint. To address these challenges, there is an urgent need to breed crops that are more resilient to suboptimal environments. Huge progress has recently been made in understanding the physiological, genetic and molecular bases of plant nutrition and environmental responses, paving the way towards a more sustainable agriculture. In this review, we present an overview of these progresses and strategies that could be developed to increase plant nutrient use efficiency and tolerance to abiotic stresses. As illustrated by many examples, they already led to promising achievements and crop improvements. Here, we focus on nitrogen and phosphate uptake and use efficiency and on adaptation to drought, salinity and heat stress. These examples first show the necessity of deepening our physiological and molecular understanding of plant environmental responses. In particular, more attention should be paid to investigate stress combinations and stress recovery and acclimation that have been largely neglected to date. It will be necessary to extend these approaches from model plants to crops, to unravel the relevant molecular targets of biotechnological or genetic strategies directly in these species. Similarly, sustained efforts should be done for further exploring the genetic resources available in these species, as well as in wild species adapted to unfavourable environments. Finally, technological developments will be required to breed crops that are more resilient and efficient. This especially relates to the development of multiscale phenotyping under field conditions and a wide range of environments, and use of modelling and big data management to handle the huge amount of information provided by the new molecular, genetic and phenotyping techniques.

Knowledge of turtle hatchling ecology is fundamental for managing wild populations. Information on habitat selection by turtle hatchlings is particularly important to ensure that conservation programmes that release hatchlings into the wild give them the best chances of surviving to adulthood. Currently, knowledge of the ecology of turtle hatchlings worldwide is limited, which restricts evidence-based management for threatened species. Here, we used laboratory and field experiments to test for effects of captivity on habitat selection, movement, and short-term survival of Murray River turtle hatchlings (Emydura macquarii). This species has declined > 60% since the 1970s, and a conservation plan is urgently needed to manage their recovery. In both the laboratory and field, we found that hatchlings select aquatic vegetation when it is available. Hatchlings raised in captivity for a month, however, were radio-tracked in habitats significantly further from vegetation after release, and over three times as many of these hatchlings were attacked by predators, compared to those released immediately after hatching. Aquatic vegetation is clearly an important habitat for hatchling E. macquarii, and therefore, (i) hatchling conservation should prioritise areas with appropriate aquatic vegetation, and (ii) aquatic vegetation restoration should be prioritised to ensure E. macquarii hatchling survival in the wild. Moreover, since captivity affects hatchling habitat selection, E. macquarii hatchlings should be released immediately upon hatching. Further research on soft release techniques and longer-term captivity is required to determine whether the impact of captivity can be reduced.

Conserving the world’s cultural and natural heritage is considered a key contributor to achieving the targets set out in the United Nation’s Sustainable Development Goals, yet how much attention do we pay to the methods we use to conserve and protect this heritage? With a specific focus on wooden objects of cultural heritage, this review discusses the current state-of-the-art in heritage conservation in terms of sustainability, sustainable alternatives to currently used consolidants, and new research directions that could lead to more sustainable consolidants in the future. Within each stage a thorough discussion of the synthesis mechanisms and/or extraction protocols, particularly for bio-based resources is provided, evaluating resource usage and environmental impact. This is intended to give the reader a better understanding of the overall sustainability of each different approach and better evaluate consolidant choices for a more sustainable approach. The challenges facing the development of sustainable consolidants and recent research that is likely to lead to highly sustainable new consolidant strategies in the future are also discussed. This review aims to contribute to the ongoing discussion of sustainable conservation and highlight the role that consolidants play in truly sustainable heritage conservation., Forests, 13 (1), ISSN:1999-4907

Transposable elements (TEs) are an important source of genome plasticity across the tree of life. Drift and natural selection are important forces shaping TE distribution and accumulation. Fungi, with their multifaceted phenotypic diversity and relatively small genome size, are ideal models to study the role of TEs in genome evolution and their impact on the host’s ecological and life history traits. Here we present an account of all TEs found in a high-quality reference genome of the lichen-forming fungus Umbilicaria pustulata, a macrolichen species comprising two climatic ecotypes: Mediterranean and cold temperate. We trace the occurrence of the newly identified TEs in populations along three elevation gradients using a Pool-Seq approach to identify TE insertions of potential adaptive significance. We found that TEs cover 21.26% of the 32.9 Mbp genome, with LTR Gypsy and Copia clades being the most common TEs. We identified 28 insertions displaying consistent insertion frequency differences between the two host ecotypes across the elevation gradients. Most of the highly differentiated insertions were located near genes, indicating a putative function. This pioneering study of the content and climate niche-specific distribution of TEs in a lichen-forming fungus contributes to understanding the roles of TEs in fungal evolution.

Species identification is a critical factor for obtaining accurate forest inventories. This paper compares the same method of tree species identification (at the individual crown level) across three different types of airborne laser scanning systems (ALS): two linear lidar systems (monospectral and multispectral) and one single-photon lidar (SPL) system to ascertain whether current individual tree crown (ITC) species classification methods are applicable across all sensors. SPL is a new type of sensor that promises comparable point densities from higher flight altitudes, thereby increasing lidar coverage. Initial results indicate that the methods are indeed applicable across all of the three sensor types with broadly similar overall accuracies (Hardwood/Softwood, 83–90%; 12 species, 46–54%; 4 species, 68–79%), with SPL being slightly lower in all cases. The additional intensity features that are provided by multispectral ALS appear to be more beneficial to overall accuracy than the higher point density of SPL. We also demonstrate the potential contribution of lidar time-series data in improving classification accuracy (Hardwood/Softwood, 91%; 12 species, 58%; 4 species, 84%). Possible causes for lower SPL accuracy are (a) differences in the nature of the intensity features and (b) differences in first and second return distributions between the two linear systems and SPL. We also show that segmentation (and field-identified training crowns deriving from segmentation) that is performed on an initial dataset can be used on subsequent datasets with similar overall accuracy. To our knowledge, this is the first study to compare these three types of ALS systems for species identification at the individual tree level.

Invasive aquatic macrophytes tend to reproduce and spread through vegetative means, often via fragmentary propagules. Dispersal among aquatic sites may occur overland via attachment to various vectors, or within river systems by directional water currents. However, for many species the relationship between fragment size and resumption of growth is unknown. Here, we assessed resumption of growth of apical and mid-stem fragments of invasive Crassula helmsii, Elodea canadensis and Lagarosiphon major. Proportionally, apical fragments tended to more readily resume growth than mid-stem sections, especially for E. canadensis and L. major (80–100%). However, viability did not scale linearly with increasing fragment size, which suggests that fragment size is not a singular determinant of propagule fitness. Nevertheless, longer fragments generally produced greater numbers of shoots and roots, but root production significantly differed among species and was determined through an interaction between plant section, species and fragment length. Overall, all species produced new shoots and roots from fragments as small as 10 mm. C. helmsii mid-stem fragments standardised by node counts did not display new growth (up to 10 nodes), while E. canadensis tended to show greater shoot and root production with increasing node counts. It is evident that a medium to high proportion of small fragmentary propagules of these invasive macrophytes can retain viability. These data have clear implications for understanding the dispersal of these invasive species and their management. Specifically, cutting and dredging may increase rather than decrease infestations, especially in downstream directions. Thus, in the absence of adequate fragment containment, current short-term control strategies may in fact be counterproductive.

International audience; Tree architecture shows large genotypic variability, but how this affects water-deficit responses is poorly understood. To assess the possibility of reaching ideotypes with adequate combinations of architectural and functional traits in the face of climate change, we combined high-throughput field phenotyping and genome-wide association studies (GWAS) on an apple tree (Malus domestica) core-collection. We used terrestrial light detection and ranging (T-LiDAR) scanning and airborne multispectral and thermal imagery to monitor tree architecture, canopy shape, light interception, vegetation indices and transpiration on 241 apple cultivars submitted to progressive field soil drying. GWAS was performed with single nucleotide polymorphism (SNP)-by-SNP and multi-SNP methods. Large phenotypic and genetic variability was observed for all traits examined within the collection, especially canopy surface temperature in both well-watered and water deficit conditions, suggesting control of water loss was largely genotype-dependent. Robust genomic associations revealed independent genetic control for the architectural and functional traits. Screening associated genomic regions revealed candidate genes involved in relevant pathways for each trait. We show that multiple allelic combinations exist for all studied traits within this collection. This opens promising avenues to jointly optimize tree architecture, light interception and water use in breeding strategies. Genotypes carrying favourable alleles depending on environmental scenarios and production objectives could thus be targeted.

Invasive alien species continue to spread and proliferate in waterways worldwide, but environmental drivers of invasion dynamics lack assessment. Knowledge gaps are pervasive in the Global South, where the frequent heavy human‐modification of rivers provides high opportunity for invasion. In southern Africa, the spatio‐temporal ecology of a widespread and high‐impact invasive alien snail, Tarebia granifera, and its management status is understudied. Here, an ecological assessment was conducted at seven sites around Nandoni Reservoir on the Luvuvhu River in South Africa. The distribution and densities of T. granifera were mapped and the potential drivers of population structure were explored. T. granifera was widespread at sites impacted to varying extents due to anthropogenic activity, with densities exceeding 500 individuals per square meter at the most impacted areas. T. granifera predominantly preferred shallow and sandy environments, being significantly associated with sediment (i.e., chlorophyll‐a, Mn, SOC, SOM) and water (i.e., pH, conductivity, TDS) variables. T. granifera seemed to exhibit two recruitment peaks in November and March, identified via size‐based stock assessment. Sediment parameters (i.e., sediment organic matter, sediment organic carbon, manganese) and water chemistry (i.e., pH, total dissolved solids, conductivity) were found to be important in structuring T. granifera populations, with overall snail densities highest during the summer season. We provide important autecological information and insights on the distribution and extent of the spread of T. granifera. This may help in the development of invasive alien snail management action plans within the region, as well as modelling efforts to predict invasion patterns elsewhere based on environmental characteristics., Alexander von Humboldt‐Stiftung http://dx.doi.org/10.13039/100005156, National Research Foundation http://dx.doi.org/10.13039/501100001321, University of Venda http://dx.doi.org/10.13039/501100008976

Large changes in the Arctic carbon balance are expected as warming linked to climate change threatens to destabilize ancient permafrost carbon stocks. The eddy covariance (EC) method is an established technique to quantify net losses and gains of carbon between the biosphere and atmosphere at high spatiotemporal resolution. Over the past decades, a growing network of terrestrial EC tower sites has been established across the Arctic, but a comprehensive assessment of the network's representativeness within the heterogeneous Arctic region is still lacking. This creates additional uncertainties when integrating flux data across sites, for example when upscaling fluxes to constrain pan-Arctic carbon budgets and changes therein. This study provides an inventory of Arctic (here > = 60∘ N) EC sites, which has also been made available online (https://cosima.nceas.ucsb.edu/carbon-flux-sites/, last access: 25 January 2022). Our database currently comprises 120 EC sites, but only 83 are listed as active, and just 25 of these active sites remain operational throughout the winter. To map the representativeness of this EC network, we evaluated the similarity between environmental conditions observed at the tower locations and those within the larger Arctic study domain based on 18 bioclimatic and edaphic variables. This allows us to assess a general level of similarity between ecosystem conditions within the domain, while not necessarily reflecting changes in greenhouse gas flux rates directly. We define two metrics based on this representativeness score: one that measures whether a location is represented by an EC tower with similar characteristics (ER1) and a second for which we assess if a minimum level of representation for statistically rigorous extrapolation is met (ER4). We find that while half of the domain is represented by at least one tower, only a third has enough towers in similar locations to allow reliable extrapolation. When we consider methane measurements or year-round (including wintertime) measurements, the values drop to about 1/5 and 1/10 of the domain, respectively. With the majority of sites located in Fennoscandia and Alaska, these regions were assigned the highest level of network representativeness, while large parts of Siberia and patches of Canada were classified as underrepresented. Across the Arctic, mountainous regions were particularly poorly represented by the current EC observation network. We tested three different strategies to identify new site locations or upgrades of existing sites that optimally enhance the representativeness of the current EC network. While 15 new sites can improve the representativeness of the pan-Arctic network by 20 %, upgrading as few as 10 existing sites to capture methane fluxes or remain active during wintertime can improve their respective ER1 network coverage by 28 % to 33 %. This targeted network improvement could be shown to be clearly superior to an unguided selection of new sites, therefore leading to substantial improvements in network coverage based on relatively small investments.

Microbial communities often harbor overwhelming species and gene diversity, making it challenging to determine the important units to study this diversity. We argue that the reduced, and thus tractable, microbial diversity of manmade salterns provides an ideal system to advance this cornerstone issue. We review recent time-series genomic and metagenomic studies of the saltern-dominating bacterial and archaeal taxa to show that these taxa form persistent, sequence-discrete, species-like populations. While these populations harbor extensive intra-population gene diversity, even within a single saltern site, only a small minority of these genes appear to be functionally important during environmental perturbations. We outline an approach to detect and track such populations and their ecologically important genes that should be broadly applicable., This work was partly funded by the US National Science Foundation, awards #1831582 and #1759831 (to KTK), and by the projects CLG2015_66686-C3-1-P, PGC2018-096956-B-C41 and RTC-2017-6405-1 of the Spanish Ministry of Science, Innovation and Universities (to RRM), which were also supported with European Regional Development Fund (FEDER) funds. RRM acknowledges the financial support of the sabbatical stay at Georgia Tech by the grant PRX18/00048 also from the Spanish Ministry of Science, Innovation and Universities.

For Inuit in the subarctic transition zone of northeastern Canada, an intimate knowledge of the environment and local biodiversity is crucial for successful traditional activities. This study examines what kinds of landscape features and habitats Inuit of Nunatsiavut recognize and name. During interviews, community members (mostly Elders) were shown photographs from the region and were asked to describe and name salient types of places in Labrador Inuttitut. The most frequently reported geographical units dealt with the region’s topography (e.g., mountain, island, flat-place), hydrology (e.g., river, bay), and superficial characteristics (e.g., bedrock, permanent snow patch). Ecological considerations were also prominent, such as plant associations and animal habitats (e.g., shrubby-place, wetland, caribou-return-to-place). Areas were often characterized by a dominant species or substrate type, being named using the plural form of the species and (or)substrate (e.g., “napâttuk” meaning ‘tree’ and “napâttuit” meaning ‘forest’ or “siugak” meaning ‘sand’ and “siugalak” meaning ‘sandy-area’). Some types of places reported by Inuit were significant mainly for traditional activities (e.g., berry-patch, seal-place, dry-wood-place, danger-place), aiding navigation and resource finding. Integrating Inuit conceptions of ecosystems and their component landscape units with those of contemporary science can improve our understanding of subarctic ecology, benefit climate change adaptation strategies, and Inuit language as well as culture conservation initiatives.

International audience; Aquatic plants are crucial for the proper functioning of aquatic environments. So far, mixotrophy, widespread in aquatic microbial communities and in certain terrestrial plants, has been studied rarely in aquatic plants other than carnivorous ones. New evidence, particularly in Lemna and other close genera, suggests that mixotrophy is much more widespread than previously thought. Three processes could be involved, namely biotrophic associations, capture of prey (e.g., in carnivorous plants), and absorbotrophy (uptake of dissolved organic carbon). The latter process seems to be the most probable hypothesis in regard to the physiology of aquatic plants, but further research at both organism and cellular levels is needed to understand and clarify the processes involved and their importance. This opinion opens a new window of opportunity in aquatic ecology, with possible unsuspected applications in water management.

This study aims to determine the palaeoenvironmental characteristics and activity patterns of Obrovac-type archaeological sites in Western Serbia, dated to the Late Neolithic/Early Eneolithic period, ∼5th millennium BC. These mound-like sites, enclosed by a wide ditch, that are not known in other parts of the central Balkan area, have long intrigued archaeologists investigating their origin and function over the last few decades. In this study, for the first time, organic-geochemical analysis of paleosol samples from the Obrovac-type sites was applied with the aim of palaeoenvironmental reconstruction. Additionally, organic carbon content and anion analysis of 58 subsoil samples from these settlements were performed to determine the use of space and activity zones. The analysis of biomarkers from selected sites suggests significant plant biodiversity in the Macva region during the Late Neolithic/Early Eneolithic. Distribution of n-alkanes with the maximum at n-C25 and predominance of C30 hop-22(29)-ene among hopanoids in samples from Obrovac type-sites indisputably indicates that macrophytes are a dominant source of organic matter, implying a marshy and floodplain depositional environment. On the other side, a strong signal of long-chain n-alkanes indicates the input of terrestrial plants into the precursor biomass, confirming that this environment was habitable for the first settlers in this region. Anion-based analysis delineates certain activity zones, demonstrating that Obrovac type-sites manifest rather complex spatial behavior despite their relatively small size and available space.

The marine nitrogen cycle is a main driver of ocean productivity and affects global climate. Despite decades of study, we still have an incomplete understanding of the role of the marine nitrogen cycle in the Earth system. While marine sediments play a major role in nitrogen cycling in the ocean, magnitudes and mechanisms are largely unconstrained. Recent research suggests that permeable sandy sediments on the highly energetic and dynamic continental shelf are key components of the marine nitrogen cycle, but data to quantify their contribution are lacking. Here, we use insights from measurements and modeling studies to substantiate the hypothesis that shelf sediments are an overlooked driver of the marine nitrogen cycle. Specifically, we propose that permeable shelf sediments are sites for intense nitrogen conversions and suggest a three‐pronged approach to address unresolved controversies.

The natural enemies hypothesis predicts that the abundance and diversity of antagonists such as predators and parasitoids of herbivores increases with the diversity of plants, which can lead to more effective top-down control of insect herbivores. However, although the hypothesis has received large support in agricultural systems, fewer studies have been conducted in forest ecosystems and a comprehensive synthesis of previous research is still lacking.We conducted a meta-analysis of 65 publications comparing the diversity, abundance or activity of various groups of natural enemies (including birds, bats, spiders and insect parasitoids) in pure vs. mixed forest stands. We tested the effects of forest biome, natural enemy taxon and type of study (managed vs experimental forest).We found a significant positive effect of forest tree diversity on natural enemy abundance and diversity but not on their activity. The effect of tree diversity on natural enemies was stronger towards lower latitudes but was not contingent on the natural enemy taxon level.Overall, our study contributes toward a better understanding of the “natural enemies hypothesis” in forest systems and provides new insights about the mechanisms involved. Furthermore, we outline potential avenues for strengthening forest resistance to the growing threat of herbivorous insects.

Understanding the drivers of biodiversity in cities is a central goal of urban ecology. There is currently intense scientific and public interest in the factors that influence pollinator diversity in cities and their surroundings. Existing studies point to a variety of landscape and local factors as potentially important, including urbanization (often defined as impervious surface cover in the surrounding lands), tree canopy cover and the diversity and abundance of locally flowering plants. However, few studies have sought to weigh the relative importance of these predictors of bee community metrics. Using a set of 27 residential yards chosen to represent a gradient of both urbanization and tree canopy cover at a landscape scale, we used pan trapping and netting to assess the abundance and diversity of local bee communities across the City of Ottawa, Ontario, Canada. Surprisingly, the landscape factors (urbanization and tree cover) described only a tiny fraction (

Reassembling ecological communities and rebuilding habitats through active restoration treatments require curating the selection of plant species to use in seeding and planting mixes. Ideally, these mixes should be assembled based on attributes that support ecosystem function and services, promote plant and animal species interactions and ecological networks in restoration while balancing project constraints. Despite these critical considerations, it is common for species mixes to be selected opportunistically. Reframing the selection of seed mixes for restoration around ecological objectives is essential for success but accessible methods and tools are needed to support this effort. We developed a framework to optimize species seed mixes based on prioritizing plant species attributes to best support different objectives for ecosystem functions, services and trophic relationships such as pollination, seed dispersal and herbivory. We compared results to approaches where plant species are selected to represent plant taxonomic richness, dominant species and at random. We tested our framework in European alpine grasslands by identifying 176 plant species characteristic of the species pool, and identified 163 associated attributes affiliated to trophic relationships, ecosystem functions and services. In all cases, trophic relationships, ecosystem functions and services can be captured more efficiently through objective-based prioritization using the functional identity of plant species. Solutions (plant species lists) can be compared quantitatively, in terms of costs, species or objectives. We confirm that a random draw of plant species from the regional plant species pool cannot be assumed to support other trophic groups and ecosystem functions and services. Synthesis and Applications. Our framework is presented as a proof-of-concept to help restoration practitioners better apply quantitative decision support to plant species selection to efficiently meet ecological restoration outcomes. Our approach may be tailored to any restoration initiative, habitat or restoration targets where seeding or planting mixes will be applied in active treatments. As global priority and resources are increasingly placed into restoration, this approach could be advanced to help make efficient decisions for many stages of the restoration process.

Complex assemblages of microbes in the surface ocean are responsible for approximately half of global carbon fixation. The persistence of high taxonomic diversity despite competition for a small suite of relatively homogeneously distributed nutrients, that is, 'the paradox of the plankton', represents a long-standing challenge for ecological theory. Here we find evidence consistent with temporal niche partitioning of nitrogen assimilation processes over a diel cycle in the North Pacific Subtropical Gyre. We jointly analysed transcript abundances, lipids and metabolites and discovered that a small number of diel archetypes can explain pervasive periodic dynamics. Metabolic pathway analysis of identified diel signals revealed asynchronous timing in the transcription of nitrogen uptake and assimilation genes among different microbial groups-cyanobacteria, heterotrophic bacteria and eukaryotes. This temporal niche partitioning of nitrogen uptake emerged despite synchronous transcription of photosynthesis and central carbon metabolism genes and associated macromolecular abundances. Temporal niche partitioning may be a mechanism by which microorganisms in the open ocean mitigate competition for scarce resources, supporting community coexistence.

One promising approach to mitigate the negative impacts of insect pests in forests is to adapt forestry practices to create ecosystems that are more resistant and resilient to biotic disturbances. At the stand scale, local stand management practices often cause idiosyncratic effects on forest pests depending on the environmental context and the focal pest species. However, increasing tree diversity appears to be a general strategy for reducing pest damage across several forest types. At the landscape scale, increasing forest heterogeneity (e.g., intermixing different forest types and/or age classes) represents a promising frontier for improving forest resistance and resilience and for avoiding large-scale outbreaks. In addition to their greater resilience, heterogeneous forest landscapes frequently support a wide range of ecosystem functions and services. A challenge will be to develop cooperation and coordination among multiple actors at spatial scales that transcend historical practices in forest management.

SUMMARY Knowing the pre-collisional extent of the northern Indian Plate margin (‘Greater India’) is vital to understanding the tectonic evolution of the India–Asia collision and the formation of the Himalayan–Tibetan orogen. However, suitable geological units for palaeomagnetic investigations along the Himalayan belt are limited, which makes it difficult to reconstruct Greater India during the pre-collisional period in Late Cretaceous to Palaeogene. Often the palaeomagnetic results from the Zongpu Formation at Gamba in southern Tibet (∼88.5°E) were used for estimates of Greater India, but their validity was recently questioned. As a contribution to closing the data gap, we performed a palaeomagnetic study of the Palaeocene/Lower Eocene Dibling limestone (DL) in the western Tethyan Himalaya of Zanskar (34.0°N/76.6°E). The results from 27 sites revealed a well grouping (k = 71.7) syntectonic magnetization with best grouping at 52 per cent unfolding. The remagnetization of the DL was acquired shortly after ∼54 Ma, at the latest at ∼49 Ma, and is probably carried by fine-grained magnetite formed during the early orogenic phase. Assuming proportional tilting of the fold limbs, the corresponding palaeolatitude of 11.8 ± 2.4°N suggests a maximum Greater India extent of 810 ± 420 km and a first continental contact with the southern Eurasian margin at ∼12°N in the western part of the suture zone. The tectonostratigraphic equivalence of the DL with the Zongpu Formation at Gamba and a great similarity in their magnetic properties supports a secondary origin of the Gamba results. Through understanding the mechanism of remagnetization in the DL, an early orogenic remanence acquisition is also indicated for the Zongpu Formation, and thus the Gamba results deserve further credit for Greater India reconstructions. However, we note a large inconsistency of the available Late Cretaceous and Palaeogene palaeolatitude data from the Tethyan Himalaya by up to ∼20°, corresponding to differences of up to ∼2000 km in the size of Greater India. These discrepancies require further palaeomagnetic work in the Tethyan Himalaya, and in particular we recommend comparative studies at same locations and of same units.

Monitoring forest dynamics is of critical importance for both sustainable forest management and conservation purposes. Light detection and ranging (lidar) data provide a detailed representation of the 3-D structure of forest stands that can be used to analyze a number of trees and stand characteristics. Recently, multiple lidar acquisitions over the same area are becoming more common allowing changes in stand attributes to be assessed over time. In order to effectively utilize such multitemporal data sets for forest dynamics monitoring, we propose a method for unsupervised change detection (CD) of lidar data based on polar change vector analysis (CVA). The proposed method involves extracting relevant lidar point cloud metrics for a given area over time. Pixel-wise difference vectors of the metrics are then converted from Cartesian to polar coordinates to represent the magnitude and direction of change. Finally, the change vectors are analyzed in the polar domain to automatically discriminate between the different classes of change. The method is applied to a multitemporal lidar data set of coniferous forest on Vancouver Island, British Columbia, Canada, impacted by various types of land cover change. The experimental results demonstrate that the proposed method is capable of automatically discriminating between different classes of lidar change.

The collection of environmental and biodiversity data is essential to manage, preserve and restore forests, but this task remains challenging due to the inaccessibility of these ecosystems. Compared to human intervention, aerial robots can access tree canopies, but their limited flight time and noise continue to stall widespread application. To address this challenge, we present a perching mechanism which allows small drones to rest on overhanging branches and extend their mission while remaining silent. We developed an origami spine with two folding flaps containing a layer of high-friction material. When the spine engages with a branch, the flaps open and conform to irregular branch surfaces generating sufficient friction to support the weight of a drone. With HEDGEHOG, a drone integrating multiple spines on a protective cage, we demonstrated its application in a controlled indoor as well as in a forest environment. We modelled the perching strategy and measured the effects of materials and geometric parameters on the drone's perching performance. By leveraging interactions with nature, our drone can perch on tree branches with diameters up to 86 mm and inclined up to +-15 and potentially remain in the canopy for extended periods of time to acquire data or monitor returning wildlife. ISSN:2377-3766

The dispersal of marine organisms can be restricted by a set of isolation mechanisms including hard barriers or hydrological features. In the Western Atlantic Ocean, the Amazon River discharge has been shown to act as a biogeographical barrier responsible for the differences in reef fish communities between Caribbean Sea and Northeast Brazil continental shelves. Here, we compare the diversity of all Animalia phyla from biogeographic ecoregions along the Tropical Western Atlantic continental shelf to test the hypothesis that the Amazon River plume spatially structures species diversity. For that, we used beta diversity estimators and multivariate ecological analysis on a database of species occurrence of the whole animal kingdom including 175,477 occurrences of 8,375 species from six ecoregions along the Western Tropical Atlantic. Results of the whole animal kingdom and the richest phyla showed that the Caribbean Sea and Tropical Brazil ecoregions are isolated by the Amazon River Plume, broadening and confirming the hypothesis that it acts as a soft barrier to animal dispersal in the Western Tropical Atlantic. Species sharing is larger northwestwards, in direction of the Caribbean than the opposite direction. Beyond species isolation due to local characteristics such as low salinity and high turbidity, our results suggest the dominant northwestward currents probably play a major role in animal dispersion: it enhances the flux of larvae and other planktonic organisms with reduced mobility from Brazil to Caribbean and hinders their contrary movement. Thus, the Amazon area is a strong barrier for taxa with reduced dispersal capacity, while species of pelagic taxa with active swimming may transpose it more easily.

A tower-based global navigation satellite system reflectometry (GNSS-R) experiment is set up in an Arctic wetland environment for investigating the possibility of monitoring wetland inundation and freeze/thaw (FT) dynamics which are additionally impacted by snow on the ground. Effects of inundation, snow cover, and soil FT state on observed GNSS-R signal-to-noise ratios (SNRs) are analyzed for horizontal (H) and vertical (V) polarizations. A simple classification approach is suggested to detect the inundated, frozen, or thawed soil state. A simple forward reflectivity model is formulated to evaluate the influence of snow cover, overlying frozen, or thawed soil, on the reflected GNSS signals. Reflectivity time series are simulated in H- and V-polarizations using in situ observations of the Arctic wetland site. The simulations are used to verify the tower-based observations, which show a significant impact of wet snow on reflectivity during melting conditions in spring. The observed SNR is strongly correlated with the Sentinel-1 backscatter coefficient. Generally, soil states detected by GNSS-R are in high agreement with ground truth soil states, especially for inundated and frozen soils. Wet snow conditions, however, complicate the correct timing estimation of soil thawing by inducing reflectivities of a similar order as thawing soil. It is recommended that GNSS-R land application models and retrieval algorithms consider snow cover effects to reduce false classification, especially in FT detection. Overall, the outcome of this study is relevant to the upcoming ESA HydroGNSS mission., This work was supported in part by the European Space Agency (ESA) Scout Mission under Grant ESA CN: 4000129140/19/NL/CT and in part by the Academy of Finland under Grant 325397. The GNSS-R installation was funded by the Spanish Grant RTI2018-099008-B-C22/AEI/10.13039/501100011033

The vascular flora of Britain and Ireland is among the most extensively studied in the world, but the current knowledge base is fragmentary, with taxonomic, ecological and genetic information scattered across different resources. Here we present the first comprehensive data repository of native and alien species optimized for fast and easy online access for ecological, evolutionary and conservation analyses. The inventory is based on the most recent reference flora of Britain and Ireland, with taxon names linked to unique Kew taxon identifiers and DNA barcode data. Our data resource for 3,227 species and 26 traits includes existing and unpublished genome sizes, chromosome numbers and life strategy and life-form assessments, along with existing data on functional traits, species distribution metrics, hybrid propensity, associated biomes, realized niche description, native status and geographic origin of alien species. This resource will facilitate both fundamental and applied research and enhance our understanding of the flora’s composition and temporal changes to inform conservation efforts in the face of ongoing climate change and biodiversity loss., Measurement(s)Plant Taxonomy • Native status • Functional traits • Ellenberg indicator values • Life strategy • Associated biome • Origin of non-native species • Species distribution • Hybrid propensity • DNA barcodes • Genome size • Chromosome numberTechnology Type(s)digital curation • flow cytometry • Chromosome countsSample Characteristic - OrganismTracheophytaSample Characteristic - EnvironmentarchipelagoSample Characteristic - LocationGreat Britain • Ireland Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.16451142

Individual tree detection is critical for forest investigation and monitoring. Several existing methods have difficulties to detect trees in complex forest environment due to insufficiently mining descriptive features. This study proposes a deep learning framework based on a designed multi-channel information complementarity representation for detecting trees in complex forest using UAV laser scanning point clouds. The proposed method consists of two main stages: ground filtering and tree detection. In first stage, a modified graph convolution network with a local topological information layer is designed to separate the ground points. Unlike most existing parametric methods, our ground filtering method avoids the optimal parameters selection to adapt to different kinds of environments. For tree detection, a topdown slice (TDS) module is firstly designed to mine the vertical structure information in a top-down way. Then, a special multichannel representation (MCR) is developed to perserve different distribution patterns of points from complementary perspectives. Finally, a multi-branch network (MBNet) is proposed for individual tree detection by fusing multi-channel features, which can provide discriminative information for MBNet to detect trees more accurately. MBNet was evaluated on seven forest areas (UAV LiDAR data with the mean size of 14,000 m2 and point density of 250 points/m2). Experimental results showed that the proposed framework achieves excellent performance. Our method obtains promising performance with mean recall of 89.23% and mean F1-score of 87.04%.

Against the background of fundamentally changing political and social requirements of agricultural production, the requirement profile of farmers has changed. The future of agriculture is widely discussed. To prepare a ground for future debates and policy programme design, it is essential to obtain an understanding of which values underlie the behaviour of farmers. This paper applies Schwartz's value theory to a large quantitative survey (N = 787) of German farmers. In addition to the overall value portrait, different value portraits within the sample of farmers are analysed. Farmers of the sample first and foremost prioritise self-transcendence values followed by openness to change. Conservation and self-enhancement are ranked to be less important within the value priorities of farmers. Furthermore, three different value portraits are identifiable within the sample. These groups differ significantly in their risk attitude and involvement in structural diversification. Implications for agricultural policy design and agricultural management are derived from the results.

DNA sequences: RAD-seq GenBank accessions SRR17125662- SRR17125721, RRBS-seq GenBank accessions SRR17145241-SRR17145300; NCBI project PRJNA786007. Scripts: Github repository https://github.com/AudeCaizergues/Epigenetics_and_the_city.; International audience; Identifying the molecular mechanisms involved in rapid adaptation to novel environments and determining their predictability are central questions in evolutionary biology and pressing issues due to rapid global changes. Complementary to genetic responses to selection, faster epigenetic variations such as modifications of DNA methylation may play a substantial role in rapid adaptation. In the context of rampant urbanization, joint examinations of genomic and epigenomic mechanisms are still lacking. Here, we investigated genomic (SNP) and epigenomic (CpG methylation) responses to urban life in a passerine bird, the Great tit (Parus major). To test whether urban evolution is predictable (i.e. parallel) or involves mostly nonparallel molecular processes among cities, we analysed both SNP and CpG methylation variations across three distinct pairs of city and forest Great tit populations in Europe. Our analyses reveal a polygenic response to urban life, with both many genes putatively under weak divergent selection and multiple differentially methylated regions (DMRs) between forest and city great tits. DMRs mainly overlapped transcription start sites and promotor regions, suggesting their importance in modulating gene expression. Both genomic and epigenomic outliers were found in genomic regions enriched for genes with biological functions related to the nervous system, immunity, or behavioural, hormonal and stress responses. Interestingly, comparisons across the three pairs of city-forest populations suggested little parallelism in both genetic and epigenetic responses. Our results confirm, at both the genetic and epigenetic levels, hypotheses of polygenic and largely nonparallel mechanisms of rapid adaptation in novel environments such as urbanized areas.

This study presents the results of a field experiment conducted for assessing the crop health status of several barley and oat crop fields in Prince Edward Island, Canada. The crop fields were mapped with an unmanned aircraft system (UAS), and the crop health status was assessed through the green area index (GAI) and vegetation indices (VIs). GAI maps were produced from the UAS imagery and VIs used machine learning pipelines with several regression algorithms (multiple linear models, support vector machines, random forests, and artificial neural networks) along with a feature selection strategy. The random forests algorithm was shown to be the best algorithm for GAI prediction with an average relative root mean square error of 10.86% and a mean absolute error of 0.67. The resulting GAI maps and the regression feature space were classified with random forests to discriminate between vigorous and stressed crop areas. We achieved a mean overall accuracy of 94%. The limits of the study are also presented.