Items 1-20 of 691

    • Journal Article

      <i>Sphaeropsis sapinea</i> found as symptomless endophyte in Finland 

      Terhonen, Eeva-Liisa; Babalola, Jumoke; Kasanen, Risto; Jalkanen, Risto; Blumenstein, Kathrin
      Silva Fennica 2021; 55(1)
      The aim of this study was to determine if the ascomycete fungus Sphaeropsis sapinea (Fr.) Dyko & B. Sutton (syn. Diplodia sapinea (Fr.) Fuckel) could be cultured from surface sterilized Scots pine twigs presenting the endophytic stage of this fungus. This fungus causes the disease called Diplodia tip blight in conifers. Symptoms become visible when trees have been weakened by abiotic stressors related to temperature, drought and hailstorms. The disease is rapidly increasing and is observed regularly in Scots pine (Pinus sylvestris L.) forests in Europe. Changes in climatic conditions will gradually increase the damage of this pathogen, because it is favored by elevated temperatures and additionally the host trees will be more susceptible due to related environmental stress. Diplodia tip blight is emerging towards Northern latitudes, thus, actions to monitor the spread of S. sapinea in pine-dominated forests should be undertaken in Finland. Our aim was to search for S. sapinea in Scots pine along a transect in Finland. Branch samples were collected from healthy Scots pine, fungal endophytes were isolated and morphologically identified. Sixteen S. sapinea strains were found from four Scots pine trees from two locations. This finding confirms that S. sapinea is found as an endophyte in healthy Scots pine in Finland.
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    • Journal Article

      National Forest Inventories capture the multifunctionality of managed forests in Germany 

      Simons, Nadja K.; Felipe-Lucia, María R.; Schall, Peter; Ammer, Christian; Bauhus, Jürgen; Blüthgen, Nico; Boch, Steffen; Buscot, François; Fischer, Markus; Goldmann, Kezia; et al.
      Gossner, Martin M.Hänsel, FalkJung, KirstenManning, PeterNauss, ThomasOelmann, YvonnePena, RodicaPolle, AndreaRenner, Swen C.Schloter, MichaelSchöning, IngoSchulze, Ernst-DetlefSolly, Emily F.Sorkau, ElisabethStempfhuber, BarbaraWubet, TesfayeMüller, JörgSeibold, SebastianWeisser, Wolfgang W.
      Forest Ecosystems. 2021 Jan 27;8(1):5
      Background Forests perform various important ecosystem functions that contribute to ecosystem services. In many parts of the world, forest management has shifted from a focus on timber production to multi-purpose forestry, combining timber production with the supply of other forest ecosystem services. However, it is unclear which forest types provide which ecosystem services and to what extent forests primarily managed for timber already supply multiple ecosystem services. Based on a comprehensive dataset collected across 150 forest plots in three regions differing in management intensity and species composition, we develop models to predict the potential supply of 13 ecosystem services. We use those models to assess the level of multifunctionality of managed forests at the national level using national forest inventory data. Results Looking at the potential supply of ecosystem services, we found trade-offs (e.g. between both bark beetle control or dung decomposition and both productivity or soil carbon stocks) as well as synergies (e.g. for temperature regulation, carbon storage and culturally interesting plants) across the 53 most dominant forest types in Germany. No single forest type provided all ecosystem services equally. Some ecosystem services showed comparable levels across forest types (e.g. decomposition or richness of saprotrophs), while others varied strongly, depending on forest structural attributes (e.g. phosphorous availability or cover of edible plants) or tree species composition (e.g. potential nitrification activity). Variability in potential supply of ecosystem services was only to a lesser extent driven by environmental conditions. However, the geographic variation in ecosystem function supply across Germany was closely linked with the distribution of main tree species. Conclusions Our results show that forest multifunctionality is limited to subsets of ecosystem services. The importance of tree species composition highlights that a lack of multifunctionality at the stand level can be compensated by managing forests at the landscape level, when stands of complementary forest types are combined. These results imply that multi-purpose forestry should be based on a variety of forest types requiring coordinated planning across larger spatial scales.
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    • Journal Article

      Low Population Differentiation but High Phenotypic Plasticity of European Beech in Germany 

      Müller, Markus; Kempen, Tanja; Finkeldey, Reiner; Gailing, Oliver
      Forests 2020; 11(12) p.1-14: Art. 1354
      Drought is increasingly impairing the vitality of European beech (Fagus sylvatica L.) in several regions of its distribution range. In times of climate change, adaptive traits such as plant phenology and frost tolerance are also becoming more important. Adaptive patterns of European beech seem to be complex, as contrasting results regarding the relative effect of phenotypic plasticity and genetic variation in trait variation have been reported. Here, we used a large translocation experiment comprising more than 15,500 seedlings in three regions of Germany to investigate local adaptation and phenotypic plasticity in beech. We found low population differentiation regarding plant survival, and plant height increment, but high phenotypic plasticity for these traits. Survival showed a positive correlation with temperature variables and a less pronounced and negative correlation with precipitation-related variables. This suggests a predominant effect of temperature and growing degree days on the survival of beech seedlings under moderate drought stress. The high phenotypic plasticity may help beech to cope with changing environmental conditions, albeit increasing drought stress may make adaptive changes necessary in the long term.
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    • Journal Article

      Local Responses and Systemic Induced Resistance Mediated by Ectomycorrhizal Fungi 

      Dreischhoff, Steven; Das, Ishani S.; Jakobi, Mareike; Kasper, Karl; Polle, Andrea
      Frontiers in Plant Science 2020; 11 p.1-20: Art. 590063
      Ectomycorrhizal fungi (EMF) grow as saprotrophs in soil and interact with plants, forming mutualistic associations with roots of many economically and ecologically important forest tree genera. EMF ensheath the root tips and produce an extensive extramatrical mycelium for nutrient uptake from the soil. In contrast to other mycorrhizal fungal symbioses, EMF do not invade plant cells but form an interface for nutrient exchange adjacent to the cortex cells. The interaction of roots and EMF affects host stress resistance but uncovering the underlying molecular mechanisms is an emerging topic. Here, we focused on local and systemic effects of EMF modulating defenses against insects or pathogens in aboveground tissues in comparison with arbuscular mycorrhizal induced systemic resistance. Molecular studies indicate a role of chitin in defense activation by EMF in local tissues and an immune response that is induced by yet unknown signals in aboveground tissues. Volatile organic compounds may be involved in long-distance communication between below- and aboveground tissues, in addition to metabolite signals in the xylem or phloem. In leaves of EMF-colonized plants, jasmonate signaling is involved in transcriptional re-wiring, leading to metabolic shifts in the secondary and nitrogen-based defense metabolism but cross talk with salicylate-related signaling is likely. Ectomycorrhizal-induced plant immunity shares commonalities with systemic acquired resistance and induced systemic resistance. We highlight novel developments and provide a guide to future research directions in EMF-induced resistance.
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    • Journal Article

      Predicting Tree Sap Flux and Stomatal Conductance from Drone-Recorded Surface Temperatures in a Mixed Agroforestry System—A Machine Learning Approach 

      Ellsäßer, Florian; Röll, Alexander; Ahongshangbam, Joyson; Waite, Pierre-André; Hendrayanto; Schuldt, Bernhard; Hölscher, Dirk
      Remote Sensing 2020; 12(24) p.1-20: Art. 4070
      Plant transpiration is a key element in the hydrological cycle. Widely used methods for its assessment comprise sap flux techniques for whole-plant transpiration and porometry for leaf stomatal conductance. Recently emerging approaches based on surface temperatures and a wide range of machine learning techniques offer new possibilities to quantify transpiration. The focus of this study was to predict sap flux and leaf stomatal conductance based on drone-recorded and meteorological data and compare these predictions with in-situ measured transpiration. To build the prediction models, we applied classical statistical approaches and machine learning algorithms. The field work was conducted in an oil palm agroforest in lowland Sumatra. Random forest predictions yielded the highest congruence with measured sap flux (r$^2$ = 0.87 for trees and r$^2$ = 0.58 for palms) and confidence intervals for intercept and slope of a Passing-Bablok regression suggest interchangeability of the methods. Differences in model performance are indicated when predicting different tree species. Predictions for stomatal conductance were less congruent for all prediction methods, likely due to spatial and temporal offsets of the measurements. Overall, the applied drone and modelling scheme predicts whole-plant transpiration with high accuracy. We conclude that there is large potential in machine learning approaches for ecological applications such as predicting transpiration.
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    • Journal Article

      Studies into Fungal Decay of Wood In Ground Contact—Part 1: The Influence of Water-Holding Capacity, Moisture Content, and Temperature of Soil Substrates on Fungal Decay of Selected Timbers 

      Marais, Brendan Nicholas; Brischke, Christian; Militz, Holger; Peters, Johann Hinrich; Reinhardt, Lena
      Forests 2020; 11(12) p.1-19: Art. 1284
      This article presents the results from two separate studies investigating the decay of wood in ground contact using adapted versions of laboratory-based terrestrial microcosm (TMC) tests according to CEN/TS 15083-2:2005. The first study (A) sought to isolate the effect of soil water-holding capacity (WHC$_{\text{soil}}$ [%]) and soil moisture content (MC$_{\text{soil}}$ [%WHC$_{\text{soil}}$]) on the decay of five commercially important wood species; European beech (Fagus sylvatica), English oak heartwood (Quercus robur), Norway spruce (Picea abies), Douglas-fir heartwood (Pseudotsuga menziesii), and Scots pine sapwood (Pinus sylvestris), while keeping soil temperature (Tsoil) constant. Combinations of soil mixtures with WHC$_{\text{soil}}$ of 30%, 60%, and 90%, and MC$_{\text{soil}}$ of 30%, 70%, and 95%WHC$_{\text{soil}}$ were utilized. A general trend showed higher wood decay, measured in oven-dry mass loss (ML$_{\text{wood}}$ [%]), for specimens of all species incubated in soils with WHC$_{\text{soil}}$ of 60% and 90% compared to 30%. Furthermore, drier soils (MC$_{\text{soil}}$ of 30 and 70%WHC$_{\text{soil}}$) showed higher MLwood compared to wetter soils (95%WHC$_{\text{soil}}$). The second study (B) built on the first’s findings, and sought to isolate the effect of Tsoil and MC$_{\text{soil}}$ on the decay of European beech wood, while keeping WHC$_{\text{soil}}$ constant. The study used constant incubation temperature intervals (T$_{\text{soil}}$), 5–40 °C, and alternating intervals of 10/20, 10/30, and 20/30 °C. A general trend showed drier MCsoil (60%WHC$_{\text{soil}}$), and T$_{\text{soil}}$ of 20–40 °C, delivered high wood decay (ML$_{\text{wood}}$ > 20%). Higher MC$_{\text{soil}}$ (90%WHC$_{\text{soil}}$) and T$_{\text{soil}}$ of 5–10 °C, delivered low wood decay (ML$_{\text{wood}}$ < 5%). Alternating T$_{\text{soil}}$ generally delivered less ML$_{\text{wood}}$ compared to their mean constant T$_{\text{soil}}$ counterparts (15, 20, 25 °C). The results suggest that differences in wood species and inoculum potential (WHC$_{\text{soil}}$) between sites, as well as changes in MC$_{\text{soil}}$ and T$_{\text{soil}}$ attributed to daily and seasonal weather patterns can influence in-ground wood decay rate.
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    • Journal Article

      N$_2$O isotope approaches for source partitioning of N$_2$O production and estimation of N$_2$O reduction – validation with the $^{15}$N gas-flux method in laboratory and field studies 

      Lewicka-Szczebak, Dominika; Lewicki, Maciej Piotr; Well, Reinhard
      Biogeosciences 2020; 17(22) p.5513-5537
      The approaches based on natural abundance N$_2$O stable isotopes are often applied for the estimation of mixing proportions between various N$_2$O-producing pathways as well as for estimation of the extent of N$_2$O reduction to N$_2$. But such applications are associated with numerous uncertainties; hence, their limited accuracy needs to be considered. Here we present the first systematic validation of these methods for laboratory and field studies by applying the $^{15}$N gas-flux method as the reference approach. Besides applying dual-isotope plots for interpretation of N$_2$O isotopic data, for the first time we propose a three dimensional N2O isotopocule model based on Bayesian statistics to estimate the N$_2$O mixing proportions and reduction extent based simultaneously on three N$_2$O isotopic signatures (δ$^{15}$N, δ$^{15}$N$^{\text{SP}}$, and δ$^{18}$O). Determination of the mixing proportions of individual pathways with N2O isotopic approaches often appears imprecise, mainly due to imperfect isotopic separation of the particular pathways. Nevertheless, the estimation of N$_2$O reduction is much more robust, when applying an optimal calculation strategy, typically reaching an accuracy of N$_2$O residual fraction determination of about 0.15.
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    • Journal Article

      Stem and soil nitrous oxide fluxes from rainforest and cacao agroforest on highly weathered soils in the Congo Basin 

      Iddris, Najeeb Al-Amin; Corre, Marife D.; Yemefack, Martin; van Straaten, Oliver; Veldkamp, Edzo
      Biogeosciences 2020; 17(21) p.5377-5397
      Although tree stems act as conduits for greenhouse gases (GHGs) produced in the soil, the magnitudes of tree contributions to total (soil + stem) nitrous oxide (N$_2$O) emissions from tropical rainforests on heavily weathered soils remain unknown. Moreover, soil GHG fluxes are largely understudied in African rainforests, and the effects of land-use change on these gases are identified as an important research gap in the global GHG budget. In this study, we quantified the changes in stem and soil N$_2$O fluxes with forest conversion to cacao agroforestry. Stem and soil N$_2$O fluxes were measured monthly for a year (2017–2018) in four replicate plots per land use at three sites across central and southern Cameroon. Tree stems consistently emitted N$_2$O throughout the measurement period and were positively correlated with soil N$_2$O fluxes. $^{15}$N-isotope tracing from soil mineral N to stem-emitted $^{15}$N$_2$O and correlations between temporal patterns of stem N$_2$O emissions, soil–air N$_2$O concentration, soil N$_2$O emissions and vapour pressure deficit suggest that N$_2$O emitted by the stems originated predominantly from N$_2$O produced in the soil. Forest conversion to extensively managed, mature (>20 years old) cacao agroforestry had no effect on stem and soil N$_2$O fluxes. The annual total N$_2$O emissions were 1.55 ± 0.20 kg N ha$^{−1}$ yr$^{−1}$ from the forest and 1.15 ± 0.10 kg N ha$^{−1}$ yr$^{−1}$ from cacao agroforestry, with tree N$_2$O emissions contributing 11 % to 38 % for forests and 8 % to 15 % for cacao agroforestry. These substantial contributions of tree stems to total N$_2$O emissions highlight the importance of including tree-mediated fluxes in ecosystem GHG budgets. Taking into account that our study sites' biophysical characteristics represented two-thirds of the humid rainforests in the Congo Basin, we estimated a total N$_2$O source strength for this region of 0.18 ± 0.05 Tg N$_2$O-N yr$^{−1}$.
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    • Journal Article

      Herbicide weed control increases nutrient leaching compared to mechanical weeding in a large-scale oil palm plantation 

      Formaglio, Greta; Veldkamp, Edzo; Duan, Xiaohong; Tjoa, Aiyen; Corre, Marife D.
      Biogeosciences 2020; 17(21) p.5243-5262
      Nutrient leaching in intensively managed oil palm plantations can diminish soil fertility and water quality. There is a need to reduce this environmental footprint without sacrificing yield. In a large-scale oil palm plantation in Acrisol soil, we quantified nutrient leaching using a full factorial experiment with two fertilization rates (260 kg N, 50 kg P, and 220 kg K ha$^{−1}$ yr$^{−1}$ as conventional practice and 136 kg N, 17 kg P, and 187 kg K ha$^{−1}$ yr$^{−1}$, equal to harvest export, as reduced management) and two weeding methods (conventional herbicide application and mechanical weeding as reduced management) replicated in four blocks. Over the course of 1 year, we collected monthly soil pore water at 1.5 m depth in three distinct management zones: palm circle, inter-row, and frond-stacked area. Nutrient leaching in the palm circle was low due to low solute concentrations and small drainage fluxes, probably resulting from large plant uptake. In contrast, nitrate and aluminum leaching losses were high in the inter-row due to the high concentrations and large drainage fluxes, possibly resulting from low plant uptake and low pH. In the frond-stacked area, base cation leaching was high, presumably from frond litter decomposition, but N leaching was low. Mechanical weeding reduced leaching losses of base cations compared to the conventional herbicide weeding probably because herbicides decreased ground vegetation and thus reduced soil nutrient retention. Reduced fertilization rates diminished the nitrate leaching losses. Leaching of total nitrogen in the mechanical weeding with reduced fertilization treatment (32±6 kg N ha$^{−1}$ yr$^{−1}$) was less than half of the conventional management (74±20 kg N ha$^{−1}$ yr$^{−1}$), whereas yields were not affected by these treatments. Our findings suggest that mechanical weeding and reduced fertilization should be included in the program by the Indonesian Ministry of Agriculture for precision farming (e.g., variable rates with plantation age), particularly for large-scale oil palm plantations. We further suggest including mechanical weeding and reduced fertilization in science-based policy recommendations, such as those endorsed by the Roundtable for Sustainable Palm Oil association.
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    • Journal Article

      Evapotranspiration over agroforestry sites in Germany 

      Markwitz, Christian; Knohl, Alexander; Siebicke, Lukas
      Biogeosciences 2020; 17(20) p.5183-5208
      In the past few years, the interest in growing crops and trees for bioenergy production has increased. One agricultural practice is the mixed cultivation of fast-growing trees and annual crops or perennial grasslands on the same piece of land, which is referred to as one type of agroforestry (AF). The inclusion of tree strips into the agricultural landscape has been shown – on the one hand – to lead to reduced wind speeds and higher carbon sequestration above ground and in the soil. On the other hand, concerns have been raised about increased water losses to the atmosphere via evapotranspiration (ET). Therefore, we hypothesise that short rotation coppice agroforestry systems have higher water losses to the atmosphere via ET compared to monoculture (MC) agriculture without trees. In order to test the hypothesis, the main objective was to measure the actual evapotranspiration of five AF systems in Germany and compare those to five monoculture systems in the close vicinity of the AF systems. We measured actual ET at five AF sites in direct comparison to five monoculture sites in northern Germany in 2016 and 2017. We used an eddy covariance energy balance (ECEB) set-up and a low-cost eddy covariance (EC-LC) set-up to measure actual ET over each AF and each MC system. We conducted direct eddy covariance (EC) measurement campaigns with approximately 4 weeks' duration for method validation. Results from the short-term measurement campaigns showed a high agreement between ETEC-LC and ETEC, indicated by slopes of a linear regression analysis between 0.86 and 1.3 ($R^2$ between 0.7 and 0.94) across sites. Root mean square errors of $LE_{EC-LC}$ vs. $LE_{EC}$ (where LE is the latent heat flux) were half as small as $LE_{ECEB}$ vs. $LE_{EC}$, indicating a superior agreement of the EC-LC set-up with the EC set-up compared to the ECEB set-up. With respect to the annual sums of ET over AF and MC, we observed small differences between the two land uses. We interpret this as being an effect of compensating the small-scale differences in ET next to and in between the tree strips for ET measurements on the system scale. Most likely, the differences in ET rates next to and in between the tree strips are of the same order of magnitude, but of the opposite sign, and compensate each other throughout the year. Differences between annual sums of ET from the two methods were of the same order of magnitude as differences between the two land uses. Compared to the effect of land use and different methods on ET, we found larger mean evapotranspiration indices (∑ET/∑P ) across sites for a drier than normal year (2016) compared to a wet year (2017). This indicates that we were able to detect differences in ET due to different ambient conditions with the applied methods, rather than the potentially small effect of AF on ET. We conclude that agroforestry has not resulted in an increased water loss to the atmosphere, indicating that agroforestry in Germany can be a land-use alternative to monoculture agriculture without trees.
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    • Journal Article

      In-depth studies on the modifying effects of natural ageing on the chemical structure of European spruce (Picea abies) and silver fir (Abies alba) woods 

      Ghavidel, Amir; Scheglov, Anna; Karius, Volker; Mai, Carsten; Tarmian, Asghar; Vioel, Wolfgang; Vasilache, Viorica; Sandu, Ion
      Journal of Wood Science 2020; 66(1) p.1-11: Art. 77
      Abstract Wood is usually stable under relatively dry conditions but may still undergo slow deterioration. The type of deterioration and how these processes affect the wood are important questions that need consideration if old wooden structures are to be studied and properly preserved. The aim of this paper is to establish the main structural and morphological differences between new and naturally aged European spruce (~ 150–200 years) and silver fir wood (~ 150 years). Naturally aged European spruce (a) was sourced from an outdoor part of a building constructed in the seventeenth century and naturally aged European spruce (b) were obtained from a furniture item located in a historical building from the eighteenth century. The principal age-induced changes in fir are the degradation of C–O and C=O groups in hemicellulose, according to the FTIR analysis. Degradation of cellulose and hemicelluloses was observed for spruce, with a greater effect seen in the indoor aged sample. X-ray photoelectron spectroscopy (XPS) showed that after aging C–C/C–H peaks were smaller in the spruce and fir samples, while C–O and O–C–O peaks were larger. The crystallinity index (CrI) obtained by X-ray diffraction showed that due to weathering the CrI of naturally aged spruce (a) increased compared to the new wood. The CrI of the aged spruce (b) and aged fir was lower than in the new woods. The ratios for the spruce sample, which aged indoors, were higher than those for the one aged outdoors. According to the observations made in this study, hemicellulose and cellulose are easily degraded under environmental conditions.
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    • Journal Article

      Surface Activation of Polylactic Acid-Based Wood-Plastic Composite by Atmospheric Pressure Plasma Treatment 

      Sauerbier, Philipp; Köhler, Robert; Renner, Gerrit; Militz, Holger
      Materials 2020; 13(20) p.1-13: Art. 4673
      Wood-plastic composite (WPC) based on a polylactic acid (PLA) matrix is a promising material since it is biobased, degradable, sustainable, and 3D printable. However, due to its coloring, visible layers after 3D-printing, and small build volumes of these printers, a coating or gluing of parts might be required. This study investigates the influence of a dielectric barrier discharge (DBD) plasma treatment of PLA-based WPC to activate the surface and improve, e.g., coating capabilities. X-ray photoelectron spectroscopy (XPS) measurements showed the oxidation of the surface due to the formation of carbonyl and carboxyl groups. Laser scanning microscopy revealed a surface roughening after the treatment. Contact angles of water and diiodomethane decreased significantly after the plasma treatment and the consecutively calculated surface free energy increased. Finally, two practical adhesion tests revealed an improvement of the applied acrylic dispersion coating’s adhesion to the WPC surface: The assigned cross-cut class improved, and the pull-off strength increased from 1.4 to 2.3 N/mm$^2$.
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    • Journal Article

      Legacy Effects Overshadow Tree Diversity Effects on Soil Fungal Communities in Oil Palm-Enrichment Plantations 

      Ballauff, Johannes; Zemp, Delphine Clara; Schneider, Dominik; Irawan, Bambang; Daniel, Rolf; Polle, Andrea
      Microorganisms 2020; 8(10) p.1-17: Art. 1577
      Financially profitable large-scale cultivation of oil palm monocultures in previously diverse tropical rain forest areas constitutes a major ecological crisis today. Not only is a large proportion of the aboveground diversity lost, but the belowground soil microbiome, which is important for the sustainability of soil function, is massively altered. Intermixing oil palms with native tree species promotes vegetation biodiversity and stand structural complexity in plantations, but the impact on soil fungi remains unknown. Here, we analyzed the diversity and community composition of soil fungi three years after tree diversity enrichment in an oil palm plantation in Sumatra (Indonesia). We tested the effects of tree diversity, stand structural complexity indices, and soil abiotic conditions on the diversity and community composition of soil fungi. We hypothesized that the enrichment experiment alters the taxonomic and functional community composition, promoting soil fungal diversity. Fungal community composition was affected by soil abiotic conditions (pH, N, and P), but not by tree diversity and stand structural complexity indices. These results suggest that intensive land use and abiotic filters are a legacy to fungal communities, overshadowing the structuring effects of the vegetation, at least in the initial years after enrichment plantings.
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      Implications of Development Cooperation and State Bureaucracy on Climate Change Adaptation Policy in Bangladesh 

      Rahman, Md Saifur; Sarker, Pradip Kumar; Hirono, Ryokichi; Giessen, Lukas
      Climate 2020; 8(10) p.1-24: Art. 118
      Policy action is visible in national and international climate governance. However, policy-making and its implementation often fail to generate the desired outcomes that aim to adapt to the adverse impact of climate change in a developing nation, such as Bangladesh—a country highly vulnerable to the impact of climate change. Against this backdrop, the study aims to analyze the implication of development cooperation and bureaucratic politics on the policy-making and implementation of climate change adaptation policy in Bangladesh. In doing so, the research uses national and international climate adaptation funds and the existing state administrative framework of the climate adaptation regime. Methodologically, it follows a mixed qualitative–quantitative research approach. The study discusses the following key findings: (1) the general cross-sectoral nature and thrusts of domestic and external climate adaptation funding; (2) how Bangladesh technical departments, such as that for water management, have reacted successfully to ensure the utilization of the funds is for implementing adaptation policy; (3) simultaneously, how Bangladesh bureaucracy, made of the elite, together with politics, have maintained their traditional values, practices, and structures in responding to the administrative requirements of climate adaptation funders, especially bilateral and multilateral development agencies, and (4) what changes should be brought to the bureaucratic cadre and added to the administrative setup in Bangladesh to provide a better overall impact of the adaptation policy and funding.
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      Improving precision of field inventory estimation of aboveground biomass through an alternative view on plot biomass 

      Kleinn, Christoph; Magnussen, Steen; Nölke, Nils; Magdon, Paul; Álvarez-González, Juan G; Fehrmann, Lutz; Pérez-Cruzado, César
      Forest Ecosystems. 2020 Oct 23;7(1):57
      Abstract We contrast a new continuous approach (CA) for estimating plot-level above-ground biomass (AGB) in forest inventories with the current approach of estimating AGB exclusively from the tree-level AGB predicted for each tree in a plot, henceforth called DA (discrete approach). With the CA, the AGB in a forest is modelled as a continuous surface and the AGB estimate for a fixed-area plot is computed as the integral of the AGB surface taken over the plot area. Hence with the CA, the portion of the biomass of in-plot trees that extends across the plot perimeter is ignored while the biomass from trees outside of the plot reaching inside the plot is added. We use a sampling simulation with data from a fully mapped two hectare area to illustrate that important differences in plot-level AGB estimates can emerge. Ideally CA-based estimates of mean AGB should be less variable than those derived from the DA. If realized, this difference translates to a higher precision from field sampling, or a lower required sample size. In our case study with a target precision of 5% (i.e. relative standard error of the estimated mean AGB), the CA required a 27.1% lower sample size for small plots of 100 m2 and a 10.4% lower sample size for larger plots of 1700 m2. We examined sampling induced errors only and did not yet consider model errors. We discuss practical issues in implementing the CA in field inventories and the potential in applications that model biomass with remote sensing data. The CA is a variation on a plot design for above-ground forest biomass; as such it can be applied in combination with any forest inventory sampling design.
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      Revisiting wind speed measurements using actively heated fiber optics: a wind tunnel study 

      van Ramshorst, Justus G. V.; Coenders-Gerrits, Miriam; Schilperoort, Bart; van de Wiel, Bas J. H.; Izett, Jonathan G.; Selker, John S.; Higgins, Chad W.; Savenije, Hubert H. G.; van de Giesen, Nick C.
      Atmospheric Measurement Techniques 2020; 13(10) p.5423-5439
      Near-surface wind speed is typically only measured by point observations. The actively heated fiber-optic (AHFO) technique, however, has the potential to provide high-resolution distributed observations of wind speeds, allowing for better spatial characterization of fine-scale processes. Before AHFO can be widely used, its performance needs to be tested in a range of settings. In this work, experimental results on this novel observational wind-probing technique are presented. We utilized a controlled wind tunnel setup to assess both the accuracy and the precision of AHFO under a range of operational conditions (wind speed, angles of attack and temperature difference). The technique allows for wind speed characterization with a spatial resolution of 0.3 m on a 1 s timescale. The flow in the wind tunnel was varied in a controlled manner such that the mean wind ranged between 1 and 17 m s$^{−1}$. The AHFO measurements are compared to sonic anemometer measurements and show a high coefficient of determination (0.92–0.96) for all individual angles, after correcting the AHFO measurements for the angle of attack. Both the precision and accuracy of the AHFO measurements were also greater than 95 % for all conditions. We conclude that AHFO has the potential to measure wind speed, and we present a method to help choose the heating settings of AHFO. AHFO allows for the characterization of spatially varying fields of mean wind. In the future, the technique could potentially be combined with conventional distributed temperature sensing (DTS) for sensible heat flux estimation in micrometeorological and hydrological applications.
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      Selection markers for transformation of the sequenced reference monokaryon Okayama 7/#130 and homokaryon AmutBmut of Coprinopsis cinerea 

      Dörnte, Bastian; Peng, Can; Fang, Zemin; Kamran, Aysha; Yulvizar, Cut; Kües, Ursula
      Fungal Biology and Biotechnology. 2020 Oct 12;7(1):15
      Background Two reference strains have been sequenced from the mushroom Coprinopsis cinerea, monokaryon Okayama 7/#130 (OK130) and the self-compatible homokaryon AmutBmut. An adenine-auxotrophy in OK130 (ade8-1) and a para-aminobenzoic acid (PABA)-auxotrophy in AmutBmut (pab1-1) offer selection markers for transformations. Of these two strains, homokaryon AmutBmut had been transformed before to PABA-prototrophy and with the bacterial hygromycin resistance marker hph, respectively. Results Gene ade8 encodes a bifunctional enzyme with an N-terminal glycinamide ribonucleotide synthase (GARS) and a C-terminal aminoimidazole ribonucleotide synthase (AIRS) domain required for steps 2 and 5 in the de novo biosynthesis of purines, respectively. In OK130, a missense mutation in ade8-1 rendered residue N231 for ribose recognition by the A loop of the GARS domain into D231. The new ade8+ vector pCcAde8 complements the auxotrophy of OK130 in transformations. Transformation rates with pCcAde8 in single-vector and co-transformations with ade8+-selection were similarly high, unlike for trp1+ plasmids which exhibit suicidal feedback-effects in single-vector transformations with complementation of tryptophan synthase defects. As various other plasmids, unselected pCcAde8 helped in co-transformations of trp1 strains with a trp1+-selection vector to overcome suicidal effects by transferred trp1+. Co-transformation rates of pCcAde8 in OK130 under adenine selection with nuclear integration of unselected DNA were as high as 80% of clones. Co-transformation rates of expressed genes reached 26–42% for various laccase genes and up to 67% with lcc9 silencing vectors. The bacterial gene hph can also be used as another, albeit less efficient, selection marker for OK130 transformants, but with similarly high co-transformation rates. We further show that the pab1-1 defect in AmutBmut is due to a missense mutation which changed the conserved PIKGT motif for chorismate binding in the C-terminal PabB domain to PIEGT in the mutated 4-amino-4-deoxychorismate synthase. Conclusions ade8-1 and pab1-1 auxotrophic defects in C. cinerea reference strains OK130 and AmutBmut for complementation in transformation are described. pCcAde8 is a new transformation vector useful for selection in single and co-transformations of the sequenced monokaryon OK130 which was transformed for the first time. The bacterial gene hph can also be used as an additional selection marker in OK130, making in combination with ade8+ successive rounds of transformation possible.
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    • Journal Article

      Chloroplast Haplotypes of Northern Red Oak (Quercus rubra L.) Stands in Germany Suggest Their Origin from Northeastern Canada 

      Götz, Jeremias; Krutovsky, Konstantin V.; Leinemann, Ludger; Müller, Markus; Rajora, Om P.; Gailing, Oliver
      Forests 2020; 11(9) p.1-15: Art. 1025
      Northern red oak (Quercus rubra L.) is one of the most important foreign tree species in Germany and considered as a major candidate for prospective sustainable forestry in the face of climate change. Therefore, Q. rubra was subject of many previous studies on its growth traits and attempts to infer the origin of various populations of this species using nuclear and chloroplast DNA markers. However, the exact geographic origin of German red oak stands has still not been identified. Its native range widely extends over North America, and the species can tolerate a broad range of environmental conditions. We genotyped individual trees in 85 populations distributed in Germany and North America using five chloroplast microsatellite and three novel chloroplast CAPS markers, resulting in the identification of 29 haplotypes. The new marker set enabled the identification of several new red oak haplotypes with restricted geographic origin. Some very rare haplotypes helped us narrow down the origin of Q. rubra stands in Germany, especially some stands from North Rhine-Westphalia, to the northern part of the species’ natural distribution area including the Peninsula of Nova Scotia, where the most similar haplotype composition was observed, compared to distinct German stands.
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    • Journal Article

      Siberian larch (Larix sibirica Ledeb.) mitochondrial genome assembled using both short and long nucleotide sequence reads is currently the largest known mitogenome 

      Putintseva, Yuliya A.; Bondar, Eugeniya I.; Simonov, Evgeniy P.; Sharov, Vadim V.; Oreshkova, Natalya V.; Kuzmin, Dmitry A.; Konstantinov, Yuri M.; Shmakov, Vladimir N.; Belkov, Vadim I.; Sadovsky, Michael G.; et al.
      Keech, OlivierKrutovsky, Konstantin V.
      BMC Genomics. 2020 Sep 23;21(1):654
      Background Plant mitochondrial genomes (mitogenomes) can be structurally complex while their size can vary from ~ 222 Kbp in Brassica napus to 11.3 Mbp in Silene conica. To date, in comparison with the number of plant species, only a few plant mitogenomes have been sequenced and released, particularly for conifers (the Pinaceae family). Conifers cover an ancient group of land plants that includes about 600 species, and which are of great ecological and economical value. Among them, Siberian larch (Larix sibirica Ledeb.) represents one of the keystone species in Siberian boreal forests. Yet, despite its importance for evolutionary and population studies, the mitogenome of Siberian larch has not yet been assembled and studied. Results Two sources of DNA sequences were used to search for mitochondrial DNA (mtDNA) sequences: mtDNA enriched samples and nucleotide reads generated in the de novo whole genome sequencing project, respectively. The assembly of the Siberian larch mitogenome contained nine contigs, with the shortest and the largest contigs being 24,767 bp and 4,008,762 bp, respectively. The total size of the genome was estimated at 11.7 Mbp. In total, 40 protein-coding, 34 tRNA, and 3 rRNA genes and numerous repetitive elements (REs) were annotated in this mitogenome. In total, 864 C-to-U RNA editing sites were found for 38 out of 40 protein-coding genes. The immense size of this genome, currently the largest reported, can be partly explained by variable numbers of mobile genetic elements, and introns, but unlikely by plasmid-related sequences. We found few plasmid-like insertions representing only 0.11% of the entire Siberian larch mitogenome. Conclusions Our study showed that the size of the Siberian larch mitogenome is much larger than in other so far studied Gymnosperms, and in the same range as for the annual flowering plant Silene conica (11.3 Mbp). Similar to other species, the Siberian larch mitogenome contains relatively few genes, and despite its huge size, the repeated and low complexity regions cover only 14.46% of the mitogenome sequence.
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    • Journal Article

      A new dataset on plant occurrences on smallislands, including species abundances andfunctional traits across different spatial scales 

      Schrader, Julian; Moeljono, Soetjipto; Tambing, Junus; Sattler, Cornelia; Kreft, Holger
      Biodiversity Data Journal 2020; 8 p.1-16: Art. e55275
      Background We introduce a new dataset of woody plants on 60 small tropical islands located in the Raja Ampat archipelago in Indonesia. The dataset includes incidence, abundance and functional trait data for 57 species. All islands were sampled using a standardised transect and plot design providing detailed information on plant occurrences at different spatial scales ranging from the local (plot and transect scale) to the island scale. In addition, the dataset includes information on key plant functional traits linked to species dispersal, resource acquisition and competitive strategies. The dataset can be used to address ecological questions connected to the species-area relationship and community assembly processes on small islands and in isolated habitats. New information The dataset yields detailed information on plant community structure and links incidence, abundance and functional trait data at different spatial scales. Furthermore, this is the first plant-island dataset for the Raja Ampat archipelago, a remote and poorly studied region, and provides important new information on species occurrences.
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