### Recent Submissions

• Journal Article

#### First Complete Genome Sequences of Janthinobacterium lividum EIF1 and EIF2 and their Comparative Genome Analysis ﻿

Genome Biology and Evolution p.1-21
We present the first two complete genomes of the Janthinobacterium lividum species, namely strains EIF1 and EIF2, which both possess the ability to synthesize violacein. The violet pigment violacein is a secondary metabolite with antibacterial, antifungal, antiviral, and antitumoral properties. Both strains were isolated from environmental oligotrophic water ponds in Göttingen. The strains were phylogenetically classified by ANI analysis and showed a species assignment to Janthinobacterium lividum with 97.72% (EIF1) and 97.66% (EIF2) identity. These are the first complete genome sequences of strains belonging to the species Janthinobacterium lividum. The genome of strain EIF1 consists of one circular chromosome (6,373,589 bp) with a GC-content of 61.98%. The genome contains 5,551 coding sequences, 122 rRNAs, 93 tRNAs, and 1 tm-RNA. The genome of EIF2 comprises one circular chromosome (6,399,352 bp) with a GC-content of 61.63% and a circular plasmid p356839 (356,839 bp) with a GC-content of 57.21%. The chromosome encodes 5,691 coding sequences, 122 rRNAs, 93 tRNAs, and 1 tm-RNA and the plasmid harbors 245 coding sequences. In addition to the highly conserved chromosomally encoded violacein operon, the plasmid comprises a non-ribosomal peptide synthetase cluster (NRPS) with similarity to xenoamicin, which is a bioactive compound effective against protozoan parasites.
• Journal Article

#### Mesoporous-silica-coated palladium-nanocubes as recyclable nanocatalyst in C–C-coupling reaction – a green approach ﻿

We report the straightforward design of a recyclable palladium-core–silica-shell nanocatalyst showing an excellent balance between sufficient stability and permeability. The overall process – design, catalysis and purification – is characterized by its sustainability and simplicity accompanied by a great recycling potential and ultra high yields in C–C-coupling reactions.
• Journal Article

#### Benefits and Constraints of the Agricultural Land Acquisition for Urbanization for Household Gender Equality in Affected Rural Communes: A Case Study in Huong Thuy Town, Thua Thien Hue Province, Vietnam ﻿

Land 2020; 9(8) p.1-19: Art. 249
The Vietnamese Government has implemented agricultural land acquisition for urbanization (ALAFU) since 2010 which has caused a high level of social-economic transition in the country. In this paper, we applied the gender and development approach to discover how ALAFU has influenced the household gender equality in affected areas in Thua Thien Hue province, Vietnam. The data for this paper was mainly collected from two household group surveys, four group discussions, and six key informant interviews. Group 1 covers 50 affected households whose agricultural land was acquired for urbanization, while Group 2 consists of 50 households whose agricultural land was not taken away. The findings reveal that ALAFU has led to reduced access to agricultural land for group 1, but has contributed to an increase of economic status for women in both groups by creating non-farming job opportunities with a good income. However, most of their new jobs are still informal, contain potential risks, and the unpaid care work burden is heavy. Moreover, although the rate of women participating in household decision making has increased, the quality of participation is limited. Their participation in social activities and vocational training courses has improved insignificantly. Therefore, if the Government continues to promote ALAFU, they should take structural gender inequalities into account to achieve their sustainable development goals.
• Journal Article

#### Designing the Next Generation of Fe$^0$-Based Filters for Decentralized Safe Drinking Water Treatment: A Conceptual Framework ﻿

Processes 2020; 8(6) p.1-16: Art. 745
The ambitious United Nations Sustainable Development Goal for 2030 to “leave no one behind” concerning safe drinking water calls for the development of universally applicable and affordable decentralized treatment systems to provide safe drinking water. Published results suggest that well-designed biological sand filters (BSFs) amended with metallic iron (Fe$^0$-BSFs) have the potential to achieve this goal. Fe$^0$-BSFs quantitatively remove pathogens and a myriad of chemical pollutants. The available data were achieved under various operating conditions. A comparison of independent research results is almost impossible, especially because the used Fe$^0$ materials are not characterized for their intrinsic reactivity. This communication summarizes the state-of-the-art knowledge on designing Fe$^0$-BSFs for households and small communities. The results show that significant research progress has been made on Fe$^0$-BSFs. However, well-designed laboratory and field experiments are required to improve the available knowledge in order to develop the next generation of adaptable and scalable designs of Fe$^0$-BSFs in only two years. Tools to alleviate the permeability loss, the preferential flow, and the use of exhausted filters are presented.
• Journal Article

#### Globally Abundant “Candidatus Udaeobacter” Benefits from Release of Antibiotics in Soil and Potentially Performs Trace Gas Scavenging ﻿

mSphere 2020; 5(4) p.1-17: Art. e00186-20
Verrucomicrobia affiliated with “Candidatus Udaeobacter” belong to the most abundant soil bacteria worldwide. Although the synthesis of antibiotics presumably evolved in soil, and environmental pollution with antimicrobials increases, the impact of these complex molecules on “Ca. Udaeobacter” remains to be elucidated. In this study, we demonstrate that “Ca. Udaeobacter” representatives residing in grassland as well as forest soil ecosystems show multidrug resistance and even take advantage of antibiotics release. Soils treated with up to six different antibiotics exhibited a higher “Ca. Udaeobacter” abundance than corresponding controls after 3, 8, and 20 days of incubation. In this context, we provide evidence that “Ca. Udaeobacter” representatives may utilize nutrients which are released due to antibiotic-driven lysis of other soil microbes and thereby reduce energetically expensive synthesis of required biomolecules. Moreover, genomic analysis revealed the presence of genes conferring resistance to multiple classes of antibiotics and indicated that “Ca. Udaeobacter” representatives most likely oxidize the trace gas H$_2$ to generate energy. This energy might be required for long-term persistence in terrestrial habitats, as already suggested for other dominant soil bacteria. Our study illustrates, for the first time, that globally abundant “Ca. Udaeobacter” benefits from release of antibiotics, which confers advantages over other soil bacteria and represents a so-far overlooked fundamental lifestyle feature of this poorly characterized verrucomicrobial genus. Furthermore, our study suggests that “Ca. Udaeobacter” representatives can utilize H$_2$ as an alternative electron donor. IMPORTANCE Soil bacteria have been investigated for more than a century, but one of the most dominant terrestrial groups on Earth, “Candidatus Udaeobacter,” remains elusive and largely unexplored. Its natural habitat is considered a major reservoir of antibiotics, which directly or indirectly impact phylogenetically diverse microorganisms. Here, we found that “Ca. Udaeobacter” representatives exhibit multidrug resistance and not only evade harmful effects of antimicrobials but even benefit from antibiotic pressure in soil. Therefore, “Ca. Udaeobacter” evidently affects the composition of soil resistomes worldwide and might represent a winner of rising environmental pollution with antimicrobials. In addition, our study indicates that “Ca. Udaeobacter” representatives utilize H$_2$ and thereby contribute to global hydrogen cycling. The here-reported findings provide insights into elementary lifestyle features of “Ca. Udaeobacter,” potentially contributing to its successful global dissemination.
• Journal Article

#### Effects of Modern Food Retailers on Adult and Child Diets and Nutrition ﻿

Nutrients 2020; 12(6) p.1-17: Art. 1714
In many developing countries, food environments are changing rapidly, with modern retailers—such as supermarkets—gaining in importance. Previous studies have suggested that the rise of modern retailers contributes to overweight and obesity. Effects of modern retailers on dietary quality have not been analyzed previously due to the unavailability of individual-level dietary data. Here, we address this research gap with data from randomly selected households in Lusaka, Zambia. Anthropometric and food-intake data from 930 adults and 499 children were analyzed to estimate effects of purchasing food in modern retailers on body weight, height, and dietary quality while controlling for income and other confounding factors. The food expenditure share spent in modern retailers was found to be positively associated with overweight in adults, but not in children. For children, a positive association between expenditures in modern retailers and height was identified. Modern retailers contribute to higher consumption of ultra-processed foods and calories. But they also increase protein and micronutrient intakes among adults and children, mainly through higher consumption of meat and dairy. The findings underline that modern retailers can influence diets and nutrition in positive and negative ways. Differentiated regulatory policies are needed to shape food environments for healthy food choices and nutrition.
• Journal Article

#### Mating System in a Native Norway Spruce (Picea abies [L.] KARST.) Stand-Relatedness and Effective Pollen Population Size Show an Association with the Germination Percentage of Single Tree Progenies ﻿

Diversity 2020; 12(7) p.1-18: Art. 266
Norway spruce differs little in neutral genetic markers among populations and provenances often reported, but in terms of putative adaptive traits and their candidate genes, some clear differences have been observed. This has previously been shown for crown morphotypes. Stands with mostly narrow crown shapes are adapted to high elevation conditions, but these stands are scattered, and the forest area is often occupied by planted stands with predominantly broad crowned morphotypes. This raises questions on whether this differentiation can remain despite gene flow, and on the level of gene flow between natural and planted stands growing in close neighbourhood. The locally adapted stands are a valuable seed source, the progeny of which is expected to have high genetic quality and germination ability. The presented case study is useful for spruce plantation by demonstrating evaluation of these expectations. Immigrant pollen and seeds from planted trees could be maladaptive and may alter the genetic composition of the progeny. This motivated us to study single tree progenies in a locally adapted stand with narrow crowned trees in a partial mast year at nuclear genomic simple sequence repeat (SSR) markers. Spruce is a typical open-pollinated conifer tree species with very low selfing rates, which were also observed in our study (s = 0.3–2.1%) and could be explained by efficient cross-pollination and postzygotic early embryo abortion, common in conifers. The estimated high amount of immigrant pollen found in the pooled seed lot (70.2–91.5%) is likely to influence the genetic composition of the seedlings. Notably, for individual mother trees located in the centre of the stand, up to 50% of the pollen was characterised as local. Seeds from these trees are therefore considered to retain most of the adaptive variance of the stand. Germination percentage varied greatly between half-sib families (3.6–61.9%) and was negatively correlated with relatedness and positively with effective pollen population size of the respective families. As pollen mostly originated from outside the stand and no family structures in the stand itself were found, germination differences can likely be explained by diversity differences in the individual pollen cloud.
• Journal Article

#### Towards Tree Green Crown Volume: A Methodological Approach Using Terrestrial Laser Scanning ﻿

Remote Sensing 2020; 12(11) p.1-12: Art. 1841
Crown volume is a tree attribute relevant in a number of contexts, including photosynthesis and matter production, storm resistance, shadowing of lower layers, habitat for various taxa. While commonly the total crown volume is being determined, for example by wrapping a convex hull around the crown, we present here a methodological approach towards assessing the tree green crown volume (TGCVol), the crown volume with a high density of foliage, which we derive by terrestrial laser scanning in a case study of solitary urban trees. Using the RGB information, we removed the hits on stem and branches within the tree crown and used the remaining leaf hits to determine TGCVol from k-means clustering and convex hulls for the resulting green 3D clusters. We derived a tree green crown volume index (TGCVI) relating the green crown volume to the total crown volume. This TGCVI is a measure of how much a crown is “filled with green” and scale-dependent (a function of specifications of the k-means clustering). Our study is a step towards a standardized assessment of tree green crown volume. We do also address a number of remaining methodological challenges.
• Journal Article

#### Towards full surface Brillouin zone mapping by coherent multi-photon photoemission ﻿

New Journal of Physics 2020; 22(7) p.1-6: Art. 073035
We report a novel approach for coherent multi-photon photoemission in the entire Brillouin zone with infrared light that is readily implemented in a laboratory setting. We excite a solid state material, Ag(110), with intense femtosecond laser pulses to excite higher-order multi-photon photoemission; angle-resolved electron spectroscopic acquisition records photoemission at large in-plane momenta involving optical transitions from the occupied to unoccupied bands of the sample that otherwise might remain hidden by the photoemission horizon. We propose this as a complementary ultrafast method to time- and angle-resolved two-color, e.g. infrared pump and extreme ultraviolet probe, photoemission spectroscopy, with the advantage of being able to measure and control the coherent electron dynamics.
• Journal Article

#### Effects of Different Farrowing and Rearing Systems on Post-Weaning Stress in Piglets ﻿

Agriculture 2020; 10(6) p.1-13: Art. 230
This study aimed to investigate how farrowing and rearing systems affect skin lesions, serum cortisol, and aggressive behavior as indicators for weaning stress of piglets. Between May 2016 and March 2018, in total 3144 weaning piglets from three different farrowing systems were examined: farrowing crates (FC), single-housing free-farrowing pens (FF), and group-housing of lactating sows and litters (GH). After weaning and regrouping, piglets were relocated to conventional rearing pens (conv; 5.7 m$^2$) or to wean-to-finish pens (w-f; 12.4 m$^2$). Skin lesions were scored 24 h after weaning. Blood samples were taken one week before and 24 h after weaning to analyze the individual difference in serum cortisol. Behavior was observed for 24 h after relocation. Animals raised in FC and FF had significantly more skin lesions than that of GH animals. Piglets born in GH showed lower cortisol differences and fought less and for shorter periods compared to FC and FF piglets. Piglets weaned to w-f pens showed greater cortisol changes and fought significantly longer than piglets in conv pens. Group housing during the suckling period reduced weaning stress for piglets in terms of skin lesions, serum cortisol, and aggressive behavior. Greater space allowance (w-f vs. conv) was not beneficial with regard to the investigated parameters.
• Journal Article

#### Reliable Discrimination of Green Coffee Beans Species: A Comparison of UV-Vis-Based Determination of Caffeine and Chlorogenic Acid with Non-Targeted Near-Infrared Spectroscopy ﻿

Foods 2020; 9(6) p.1-14: Art. 788
Species adulteration is a common problem in the coffee trade. Several attempts have been made to differentiate among species. However, finding an applicable methodology that would consider the various aspects of adulteration remains a challenge. This study investigated an ultraviolet–visible (UV-Vis) spectroscopy-based determination of caffeine and chlorogenic acid contents, as well as the applicability of non-targeted near-infrared (NIR) spectroscopy, to discriminate between green coffee beans of the Coffea arabica (Arabica) and Coffea canephora (Robusta) species from Java Island, Indonesia. The discrimination was conducted by measuring the caffeine and chlorogenic acid content in the beans using UV-Vis spectroscopy. The data related to both compounds was processed using linear discriminant analysis (LDA). Information about the diffuse reflectance (log 1/R) spectra of intact beans was determined by NIR spectroscopy and analyzed using multivariate analysis. UV-Vis spectroscopy attained an accuracy of 97% in comparison to NIR spectroscopy’s accuracy by selected wavelengths of LDA (95%). The study suggests that both methods are applicable to discriminate reliably among species.
• Journal Article

#### Testate Amoeba Species- and Trait-Based Transfer Functions for Reconstruction of Hydrological Regime in Tropical Peatland of Central Sumatra, Indonesia ﻿

Frontiers in Ecology and Evolution 2020; 8 p.1-15: Art. 225
Tropical peatlands play an important role in carbon storage and in water regulation on a landscape level. However, our understanding of their ecology and long-term hydrological dynamics remains limited. Transfer functions, constructed on the basis of biological indicators (proxies) with known ecological preferences, allow us to infer past environmental conditions and serve as a basis for prediction of future changes in peatlands. Here, we use testate amoebae to develop the first species- and functional trait-based transfer functions for the Southeast Asia. This provides a valuable tool for future reconstructions of past hydrological changes in tropical peatlands, their development, and climatic changes. Surface samples for testate amoeba analysis were taken in various biotopes along two transects across the Sungai Buluh peatland in Central Sumatra. The following environmental characteristics were measured: water table depth (WTD), light intensity, pH, total C and N concentrations. The analysis of the surface samples revealed 145 morphotypes of testate amoebae belonging to 25 genera. A significant fraction of the variance in testate amoeba morphotypes and functional trait composition was explained by WTD and pH. The wide WTD range (0–120 cm) seems more valuable for reconstruction than the extremely short pH gradient (2.5–3.8). Thus, transfer functions were developed only for WTD, based on weighted averaging model for morphotypes and multiple linear regression for functional traits. Both species- and trait-based model have a predictive ability for WTD reconstruction. For traits, the best performance of the model was reached by including five morphological traits: shell width, aperture shape, aperture invagination, shell shape and shell compression. We discuss the ecology of several taxa and highlight the traits, which reflect hydrological changes in this system. Though the hydrological preferences of some species are similar to those in high and middle latitude peatlands, we argue that latitudinal differences in morphospecies composition and variations in environmental relationships of species require the development of region-specific transfer functions. Moreover, our results indicate that ecological preferences of morphotypes within morphospecies also need to be considered and included in future studies.
• Journal Article

#### De novo transcriptome assembly of cold stressed clones of the hexaploid Sequoia sempervirens (D. Don) Endl. ﻿

Scientific Data 2020; 7(1) p.1-8: Art. 239
Coast redwood is a very important endemic conifer timber species in Southern Oregon and Northern California in the USA. Due to its good wood properties and fast growth rate it can be considered as a prospective timber species also in other countries with similar or changing toward similar climatic conditions due to global climate warming, such as Germany. In general, it is frost sensitive and suffers from freezing temperatures. To study genetic mechanisms of frost resistance in this species and to select the most frost tolerant trees we tested 17 clones in climate control chamber experiments and generated two de novo assemblies of the coast redwood transcriptome from a pooled RNA sample using Trinity and CLC Genomic Workbench software, respectively. The hexaploid nature of the coast redwood genome makes it very challenging to successfully assemble and annotate the coast redwood transcriptome. The de novo transcriptome assembly generated by Trinity and CLC considering only reads with a minimum length of 180 bp and contigs no less than 200 bp long resulted in 634,772 and 788,464 unigenes (unique contigs), respectively.
• Journal Article

#### Quantifying forest cover at Mount Kenya: Use of Sentinel-2 for a discrimination of tropical tree composites ﻿

African Journal of Environmental Science and Technology 2020; 14(6) p.159-176
The aim of the present study is totest ESA’s Sentinel-2 (S2) satellites (S2A and S2B) for an efficient quantification of land cover (LC) and forest compositions in a tropical environment southwest of Mount Kenya. Furthermore, outcome of the research is used to validate ESA’s S2 prototype LC 20m map of Africa that was produced in 2016. A decision tree that is based on significant altitudinal ranges was used to discriminatefour natural tree compositions that occur within the investigation area. In addition, the classification process was supported by Google Earthimages, and land use (LU) data that wereprovided by the local Kenyan Forest Service(KFS). Final classification products include four LC classes and five subclasses of forest (four natural forestsubclasses plus one non-natural forest class). Results of theJeffries-Matusita (JM) distance test show significant differences in spectral separability between all classes. Furthermore, the study identifies spectral signatures and significant wavelengths for a classification of all LC classes and forest subclasseswherewavelengths of SWIR and the red-edge domain show highestimportancefor the discrimination of tree compositions.Finally, considerable differences can be seen between the utilized multi-temporal classification set (total of 39 bands fromthree acquisition dates) and ESA’s S2 prototype LC 20m map of Africa 2016. A visual comparison of ESA’s prototypemapwithin the investigation area indicates an overrepresentation of tree cover areas (as confirmed in previous studies) andalso an underrepresentation of water.
• Journal Article

#### Upconversion photoluminescence of Ho$^{3+}$-Yb$^{3+}$ doped barium titanate nanocrystallites: Optical tools for structural phase detection and temperature probing ﻿

Scientific Reports 2020; 10(1) p.1-12: Art. 8775
Authors have explored the photo-physical properties of Ho$^{3+}$-Yb$^{3+}$ doped BaTiO$_3$ nanocrystals and proposed an intuitive method to probe temperature and crystal phase structure of the matrix. Structural phase change of doped crystals was analyzed in terms of their X-ray diffraction, and it was confirmed through second harmonic generation. We give insights on upconversion of energy of light-emission in Ho$^{3+}$-Yb$^{3+}$: BaTiO$_3$ nanocrystals upon a 980 nm laser-light excitation and subsequently, the excited state dynamics were studied with the help of dependence of upconversion luminescence on excitation power and measuring-temperature. To understand the nature of occupancies of the Ho$^{3+}$ ions at the Ti- and Ba-sites, we performed site-selective, time-resolved spectroscopic measurements at various crystal phases. Based on the lifetime analysis, it is inferred that the Ho$^{3+}$ ions are present at two types of sites in barium titanate lattice. One of those is the 6-coordinated Ti-site of low symmetry, while the other one is the 12-coordinated Ba-site of higher symmetry. The upconversion emission of the nanocrystals are found to be temperature-sensitive (12 to 300 K), indicating possible use as a self-referenced temperature probe. An analysis of the temperature dependent emissions from $^5$F$_4$ and $^5$S$_2$ levels of Ho$^{3+}$ ions, gives a maximum value of temperature sensitivity ~ 0.0095 K$^{−1}$ at 12 K. Furthermore, we observe a sharp change in the luminescence intensity at ~180 K due to a ferroelectric phase change of the sample. The correlation of upconversion luminescence with the results of X-ray diffraction and second harmonic generation at different crystal phases implies that the frequency upconversion may be used as a probe of structural change of the lattice.
• Journal Article

#### Authigenic formation of Ca-Mg carbonates in the shallow alkaline Lake Neusiedl, Austria ﻿

Biogeosciences 2020; 17(7) p.2085-2106
Despite advances regarding the microbial and organic-molecular impact on nucleation, the formation of dolomite in sedimentary environments is still incompletely understood. Since 1960, apparent dolomite formation has been reported from mud sediments of the shallow, oligohaline and alkaline Lake Neusiedl, Austria. To trace potential dolomite formation or diagenetic alteration processes in its deposits, lake water samples and sediment cores were analyzed with respect to sediment composition, hydrochemistry and bacterial community composition. Sediments comprise 20 cm of homogenous mud with 60 wt % carbonate, which overlies dark-laminated consolidated mud containing 50 wt % carbonate and plant debris. Hydrochemical measurements reveal a shift from oxic lake water with pH 9.0 to anoxic sediment pore water with pH 7.5. A decrease in SO$_2^{−4}$ with a concomitant increase in ΣH$_2$S and NH$^+_4$ from 0 to 15 cm core depth indicates anaerobic heterotrophic decomposition, including sulfate reduction. The bacterial community composition reflects the zonation indicated by the pore water chemistry, with a distinct increase in fermentative taxa below 15 cm core depth. The water column is highly supersaturated with respect to (disordered) dolomite and calcite, whereas saturation indices of both minerals rapidly approach zero in the sediment. Notably, the relative proportions of different authigenic carbonate phases and their stoichiometric compositions remain constant with increasing core depth. Hence, evidence for Ca–Mg carbonate formation or ripening to dolomite is lacking within the sediment of Lake Neusiedl. As a consequence, precipitation of high-magnesium calcite (HMC) and protodolomite does not occur in association with anoxic sediment and sulfate-reducing conditions. Instead, analytical data for Lake Neusiedl suggest that authigenic HMC and protodolomite precipitate from the supersaturated, well-mixed aerobic water column. This observation supports an alternative concept to dolomite formation in anoxic sediments, comprising Ca–Mg carbonate precipitation in the water column under aerobic and alkaline conditions.
• Journal Article

#### Non-Human Primate iPSC Generation, Cultivation, and Cardiac Differentiation under Chemically Defined Conditions ﻿

Cells 2020; 9(6) p.1-24: Art. 1349
Non-human primates (NHP) are important surrogate models for late preclinical development of advanced therapy medicinal products (ATMPs), including induced pluripotent stem cell (iPSC)-based therapies, which are also under development for heart failure repair. For effective heart repair by remuscularization, large numbers of cardiomyocytes are required, which can be obtained by efficient differentiation of iPSCs. However, NHP-iPSC generation and long-term culture in an undifferentiated state under feeder cell-free conditions turned out to be problematic. Here we describe the reproducible development of rhesus macaque (Macaca mulatta) iPSC lines. Postnatal rhesus skin fibroblasts were reprogrammed under chemically defined conditions using non-integrating vectors. The robustness of the protocol was confirmed using another NHP species, the olive baboon (Papio anubis). Feeder-free maintenance of NHP-iPSCs was essentially dependent on concurrent Wnt-activation by GSK-inhibition (Gi) and Wnt-inhibition (Wi). Generated NHP-iPSCs were successfully differentiated into cardiomyocytes using a combined growth factor/GiWi protocol. The capacity of the iPSC-derived cardiomyocytes to self-organize into contractile engineered heart muscle (EHM) was demonstrated. Collectively, this study establishes a reproducible protocol for the robust generation and culture of NHP-iPSCs, which are useful for preclinical testing of strategies for cell replacement therapies in NHP.
• Journal Article

#### Initial Survival and Development of Planted European Beech (Fagus sylvatica L.) and Small-Leaved Lime (Tilia cordata Mill.) Seedlings Competing with Black Cherry (Prunus serotina Ehrh.) ﻿

Plants 2020; 9(6) p.1-17: Art. 677
Black cherry (Prunus serotina Ehrh.) is considered one of the most invasive tree species in central Europe and causes problems for both nature conservation and silviculture. Besides mechanical control treatments, a suggested control method to prevent its ongoing spread is to underplant shade-tolerant native tree species. Therefore, we combined two mechanical treatments, with underplanting of European beech (Fagus sylvatica L.) or small-leaved lime (Tilia cordata Mill.) on fenced and unfenced plots. After the first growing season, survival rates were evaluated, and selected seedlings were destructively harvested to analyze their growth performance and leaf morphology in association with the different light regimes resulting from mechanical treatments Survival rates for both seedlings were very high (>95%). Survival rates were higher on fenced plots than on unfenced plots, most likely as result of browsing. The mortality of F. sylvatica decreased with increasing light availability on fenced plots. The mortality of T. cordata did not change along the light gradient. After one vegetation period no differences with respect to biomass allocation could be detected along the light gradient. However, the specific leaf areas of both species responded similarly, decreasing with increasing light availability. In summary, both species were able to establish and survive in the dense P. serotina understory and might have the potential to outcompete the invasive alien species in the long run.
• Journal Article

#### Root growth in light of changing magnesium distribution and transport between source and sink tissues in potato (Solanum tuberosum L.) ﻿

Scientific Reports 2020; 10(1) p.1-14: Art. 8796
This study depicts relations between magnesium (Mg) transport and re-translocation, photoassimilate partitioning, cation and ion concentrations, and finally root growth of potato under different Mg supplies. Potato plants were grown in a hydroponic culture system under different Mg regimes while investigating Mg concentrations, the expression of various Mg transporters, soluble sugars, and cations and anions in source and sink organs at different growth stages. Reports from literature about the impact of Mg deficiency on root growth are inconsistent. As Mg is known to be a phloem mobile nutrient, it is expected to be re-translocated under restricted availability of Mg from source to sink organs. Thus, we assume that plants can tolerate a slight Mg restriction without severe root growth reduction. However, under severe Mg deficiency, the process of Mg re-translocation is hampered, resulting in an impaired photoassimilate partitioning, and finally root growth. This might also explain the findings of studies claiming that Mg deficiency does not impair root growth as plants of these studies likely only suffered a slight Mg restriction. Finally, this study gives indications that an interruption of the process of Mg-re-translocation in early plant growth could be an indicator for growth reductions of the plant at a later growth stage.
• Journal Article

#### Plant intraspecific functional trait variation is related to within‐habitat heterogeneity and genetic diversity in Trifolium montanum L. ﻿

Ecology and Evolution 2020; 10(11) p.5015-5033
Intraspecific trait variation (ITV), based on available genetic diversity, is one of the major means plant populations can respond to environmental variability. The study of functional trait variation and diversity has become popular in ecological research, for example, as a proxy for plant performance influencing fitness. Up to now, it is unclear which aspects of intraspecific functional trait variation (iFD$_{CV}$) can be attributed to the environment or genetics under natural conditions. Here, we examined 260 individuals from 13 locations of the rare (semi‐)dry calcareous grassland species Trifolium montanum L. in terms of iFD$_{CV}$, within‐habitat heterogeneity, and genetic diversity. The iFD$_{CV}$ was assessed by measuring functional traits (releasing height, biomass, leaf area, specific leaf area, leaf dry matter content, F$_v$/F$_m$, performance index, stomatal pore surface, and stomatal pore area index). Abiotic within‐habitat heterogeneity was derived from altitude, slope exposure, slope, leaf area index, soil depth, and further soil factors. Based on microsatellites, we calculated expected heterozygosity (He) because it best‐explained, among other indices, iFD$_{CV}$. We performed multiple linear regression models quantifying relationships among iFD$_{CV}$, abiotic within‐habitat heterogeneity and genetic diversity, and also between separate functional traits and abiotic within‐habitat heterogeneity or genetic diversity. We found that abiotic within‐habitat heterogeneity influenced iFD$_{CV}$ twice as strong compared to genetic diversity. Both aspects together explained 77% of variation in iFD$_{CV}$ ($R^2_{adj}$=.77, $F_{2,10}$ = 21.66, p < .001). The majority of functional traits (releasing height, biomass, specific leaf area, leaf dry matter content, F$_v$/F$_m$, and performance index) were related to abiotic habitat conditions indicating responses to environmental heterogeneity. In contrast, only morphology‐related functional traits (releasing height, biomass, and leaf area) were related to genetics. Our results suggest that both within‐habitat heterogeneity and genetic diversity affect iFD$_{CV}$ and are thus crucial to consider when aiming to understand or predict changes of plant species performance under changing environmental conditions.