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Combining national forest inventories reveals distinct role of climate on tree recruitment in European forests
Full text linkTree recruitment forms an essential process in forest growth models as it determines the amount and composition of the next generation of trees and, hence, the provision of forest ecosystem services over long time spans. With global change and the hereby associated changes in environmental conditions and forest management adaptations, the common static tree recruitment modelling approaches have become largely obsolete and necessitated the development of more dynamic models. Limited by the availability of data for the parameterisation of tree recruitment processes, such models have only been developed for single species or national frameworks and largely failed to detect climatic influences. In this study, we developed a dynamic tree recruitment model for Europe, utilising National Forest Inventory data from 8 countries with more than 95,000 repeated plot observations and nearly 138,000 individual tree recruitment events. We investigated the effect of forest management, forest structure, soil characteristics, nutrient deposition and five groups of weather and climate variables on the quantity and the species composition of recruiting trees. The climatic groups spanned annual averages, intra annual averages, annual variability, intra annual extremes and a combination of the aforementioned groups. The model with the combination of climate and weather variables outperformed all other groups. We found distinct climatic effects on tree recruitment quantities linked to water limitations and temperature extremes. The results as such showed that tree recruitment quantities benefit from stable climatic conditions, high precipitation and suffer from high maximum temperatures. Increasing temperatures also facilitate the share of recruiting broadleaves. The recruitment species was largely determined by the lead species in a plot, indicating the importance of seed limitation. Furthermore, the results confirm the important role of forest structure in tree recruitment and enable forest managers to steer the next generation of trees. Especially multi-species stands show a clear advantage over single species stands regarding tree recruitment quantities and diverse species compositions. Our research enables dynamic and state-of-the-art recruitment simulations across forests in Europe. It presents a reproducible method that can be applied to forest simulation modelling frameworks
Characterization of bioactive compounds in fenugreek genotypes in varying environments: diosgenin, trigonelline, and 4-hydroxyisoleucine
Full text linkThis study investigates the effects of irrigated and non-irrigated conditions on the bioactive compound content in fenugreek (Trigonella foenum-graecum) across 31 diverse genotypes from various geographical regions. The study was conducted at Atat & uuml;rk University Research and Extension Center, T & uuml;rkiye (N 39 degrees 55'59.9", E 41 degrees 14'10.6", altitude 1789 m) during the 2021 and 2022 growing seasons. The levels of diosgenin, trigonelline, and 4-hydroxyisoleucine analyzed under irrigated and non-irrigated conditions were found to be significantly influenced by genotype, environment, and their interaction (Genotype x Environment), with a highly significant effect observed at the p < 0.001 level. The compounds analyzed included diosgenin (0.50-0.93%), trigonelline (5.22-13.65 mg g(-)(1)), and 4-hydroxyisoleucine (0.41-1.90%). Notably, genotypes such as Sivas/TR, Amasya/TR, Konya/TR and Samsun/TR exhibited higher diosgenin content across all conditions, while Spain, Malaysia, France, and India showed higher trigonelline content under irrigation. Variability in 4-hydroxyisoleucine content was observed, with some genotypes showing stability across different environmental conditions. A negative correlation between diosgenin and trigonelline was observed in fenugreek. Furthermore, Principal Component Analysis (PCA) and cluster analysis were found to be effective in revealing genetic diversity, morphological differences, and genotype adaptability. The findings highlight the potential for selecting superior genotypes for breeding programs focused on enhancing bioactive compound yields, especially under varying irrigation and non-irrigated conditions. This research emphasizes the critical role of environmental and genetic factors in optimizing the production of health-benefiting compounds in fenugreek
Oviposition behaviour of Rhagoletis completa on dead end host Cydonia oblonga
Full text linkHost finding behaviour and host acceptance for oviposition is a rather complex process amongst insects; it is a major decision that will have a direct effect on the performance of offspring. It is not uncommon that herbivorous insects oviposit on unsuitable hosts. The level of insect-host specialisation correlates with the likelihood of mis-oviposition incidence; polyphagous herbivore insect species have a higher chance to lay eggs on unsuitable hosts compared to specialised monophagous ones. Over several seasons, large numbers of walnut husk fly adults were observed on the canopy and fruit of European quince. Males were engaging in behaviours like fighting, courting, mating, and guarding oviposition sites, while females copulated, oviposited, or rested. Oviposition marks were found on quince fruits, with unhatched eggs, chorions, and newly hatched maggots inside. Molecular identification confirmed the species as Rhagoletis completa. To investigate this unusual host interaction, electrophysiological recordings were conducted on the antennae and maxillary palpi of WHF adults using quince and walnut fruit and foliage volatiles. Behavioural experiments also explored any preference for quince. The results showed that WHF adults, especially females, exhibited a positive attraction to quince fruit volatiles, indicating that their peripheral detection of volatiles is not limited to host-specific compounds. Based on these findings, we conclude that WHF adults treated quince as a suitable host for oviposition in a natural condition
Divergent Perspectives on Ecosystem-Based Adaptation: A Comparative Analysis of Government Officials and Farmers in Mountainous Communes of Thua Thien Hue Province, Vietnam
Full text linkEcosystem-based adaptation (EbA) has been widely recognized as the key strategy for supporting farmers in adapting to climate change. The success of EbA requires a cohesive alignment from the national level to community implementation. However, harmonized efforts from central governments to local farmers remain underexplored in the literature on climate change and adaptation, especially in the context of mountainous areas of Vietnam. This study applied multiple qualitative research methods, including 12 key informant interviews, six focus group discussions, and 18 in-depth interviews to explore the varying perspectives of EbA between government officials and farmers, and how these perspectives influence their involvement in governmental initiatives. Using matrix coding visualization in NVIVO, this study revealed notable differences in perceptions of EbA between government officials and farmers, which in turn impact EbA practices at the commune level. This study also found factors affecting EbA practices, including knowledge, economic priorities, institutional support, labor shortages, limited market access, and funding inadequacies. The policy implications drawn from this study are necessary for bridging top-down policy with local realities, to ensure the sustainability and effectiveness of EbA. Furthermore, this paper contributes to the EbA literature by highlighting the need for context-specific adaptation strategies to enhance the effectiveness and inclusivity of EbA practices in vulnerable communities
GIS based multi-criteria decision-making approach for dry port location analysis: The case of Ethiopia☆
Full text linkDry port construction facilitates intermodal freight transport in the import and export corridors, especially for landlocked countries. Selecting the optimal locations for dry ports is a crucial component of national planning. In this study, multi-criteria decision-making (MCDM) combined with GIS was used to map suitable sites for dry ports. Essential criteria for selecting optimum dry port locations were identified from the literature and a Simple Multi-Attribute Ranking Technique (SMART) was used for expert weighting these criteria. The results revealed that distance from road and distance from railway are the two most important criteria, while distance from a seaport is the least important. Application of the method to identify optimal dry port locations in Ethiopia showed that most of its territory is moderately suitable for dry port location. However, most of the existing dry ports in the region are found to lie within the highly suitable areas. Overall, the suitability map developed in this study provides a rich basis of information for future sustainable dry port investments
Does production diversity support dietary diversity? Evidence from pastoral and agro-pastoral households in West Pokot County, Kenya
Full text linkConsumption of part of own-produced food is regarded as a sustainable approach to attaining dietary diversity and a pathway to improved food and nutrition security. However, empirical evidence on the relationship between production diversity and dietary diversity is inconclusive, with some studies demonstrating a positive relationship while others reveal conflicting results. Furthermore, this relationship has not been examined in pastoral contexts. We used data from 502 pastoral and agro-pastoral households in West Pokot County, Kenya, to assess the relationship between production indicators and household dietary diversity. Our results show that households with more diverse production had more diverse diets. Additionally, we find that nutritional awareness, engagement in off-farm enterprises, income, market participation, and location based on agro-ecological characteristics influence dietary diversity. Our findings suggest that more diverse crop-livestock systems appropriate to the agro-ecological conditions of West Pokot may be a strategy toward addressing the nutritional inadequacies experienced in the region. Further investigation of the wider implications of such a transition is suggested
Uppföljning av blankålars lekvandring efter fångst och transport
Full text linkFångst och transport av ål nedströms vandringshinder används som bevarandeåtgärd, främst för att minska dödligheten i vattenkraftverk. I vilken utsträckning hanteringen påverkar vandringsbeteendet och på lång sikt även påverkar reproduktionen är dåligt känt. Undersökningens syfte är att genom märkning följa ålar som genomgått fångst och transport, både i närområdet och under den marina fasen av lekvandringen. Målet är att över en längre tidsperiod jämföra beteendet hos transporterade ålar med ålar som inte blivit transporterade.Försöksupplägget var att märka ålar med interna akustiska märken och externa satellitmärken i fyra experimentgrupper:1. En referensgrupp, fångad och utsatt utan transport vid Utlängan i Hanöbukten. 2. En grupp transporterad från Vänern till Göta älv. 3. En grupp transporterad från Glan till Bråviken. 4. En grupp transporterad från Mälaren till västkusten.Grupp 2 och 3 ingår i pågående åtgärder för att minska dödligheten i respektive avrinningsområde. Grupp 4 avsåg att studera effekten av fångst och transport mellan avrinningsområden.I vardera gruppen märktes 25 ålar med akustiska märken och 20 med satellitmärken. Passage av de individuellt kodade akustiska märkena registrerades under ett år vid fast utplacerade lyssnarkedjor i respektive utsättningsområden och i Östersjöns utlopp. Satellitmärkena var programmerade att lösas ut från ålen efter ett år och då sända lagrade data om simdjup och temperatur till Argos Global Satellite System.Resultaten av de akustiska märkningarna visar att beteendet under övergången från sötvatten till den marina miljön var kritisk, vilket innebar att försöksupplägget hade begränsningar. Registrering av de akustiskt märkta ålar från Vänern och Mälaren som sattes ut i Göta älv, gjordes bara i nedre delen av älven. En kontinuerlig övervakning som kunde visa i vilken utsträckning och hur länge ålarna blev kvar i estuariet saknades. Även referensgruppen saknade kontinuerlig akustisk övervakning av närområdet. Utsättningen i Bråviken hade bättre förutsättningar genom en kedja lyssnarbojar i yttre delen av fjärden. Alla försöksgrupper visade dock att en hög andel övervintrade nära utsättningsplatsen och även att många fortfarande var kvar när projektet avslutades. Skillnaden i förutsättningar gör emellertid att en detaljerad jämförelse mellan referens- och försöksgrupper inte går att göra. Ingen klar skillnad observerades mellan utsättning i samma avrinningsområde (grupp 2), och transport mellan avrinningsområden (grupp 4).Den stora andelen övervintrare tycks också förklara det oväntat stora databortfallet för satellitmärkningen. Endast cirka hälften av märkena registrerades av Argossystemet och av dessa gav 65 % alltför fragmenterade data för en säker analys. En stor andel märken utlöstes i närheten av utsättningsplatsen. Strandade och upphittade märken visade att övervintringen skett på så grunt vatten att sändning startade, men utan att märket kommit upp till ytan och kunde få kontakt med satelliterna. Ålar i alla experimentgrupper vandrade i förväntad riktning, på ostkusten mot Östersjöns utlopp och på västkusten mot norr och väster och med liknande vandringshastighet. Med det begränsade materialet kan man dock inte dra några långtgående slutsatser. Ingenting i Sammanfattning satellitmärkningarna visar på att ålar som genomgått fångst och transport beter sig uppenbart avvikande från referensålarna. En skillnad är dock att referensålarna vandrat de längsta sträckorna och i större utsträckning lämnat Östersjön.Ål är en toppredator och övervintring och kvardröjande i kustområdet kan förväntas påverka det lokala ekosystemet. Kannibalism på glasål och småål kan vara kontraproduktivt ur bevarandesynpunkt. Säl- och skarvpredation på fisk är hög i kustområdet och ett extra år före starten av lekvandringen kan potentiellt öka mortaliteten hos ål.Slutsatsen av den stora andelen övervintrare är att ål som skall användas för fångst och transport bör väljas på en tidpunkt och från en plats där man kan förvänta sig att ålen har startat lekvandringen. Detta för att undvika en potentiellt förhöjd mortalitet och kannibalism i området där ålen sätts ut. Det kan innebära en fångstplats så nära utloppet i ett vattensystem som möjligt och att man undviker långvarig sumpning.Vid uppföljning av fångst och transport av ål med hjälp av akustisk märkning bör kontinuerlig övervakning ske i övergångszonen till salt eller bräckt vatten
Plant development influences dynamic shifts in the root compartment microbiomes of wild and domesticated finger millet cultivars
Full text linkBackgroundPlant-microbe interactions in the rhizosphere and endosphere are crucial for maintaining plant health and ecosystem dynamics. These interactions are shaped by several factors, including the plant’s developmental stage, domestication, and specific root compartments. Different plant cultivars influence unique microbial communities by secreting root exudates that either support beneficial symbionts or inhibit pathogens. This study examined the microbial community structures in the endosphere and rhizosphere of wild-type finger millet and five domesticated cultivars at two developmental stages.ResultsOur results revealed that the plant developmental stage, root compartment, and domestication significantly influence the root-associated microbiomes. Interestingly, only about 8% of the core microbiota was consistently shared between the soil and plants, indicating that 92% shifted dynamically depending on plant type and developmental stage. Pseudomonadota, Actinomycedota, and Bacteroidota were the dominant bacterial phyla, while Ascomycota and Basidiomycota were the primary fungal phyla across all samples, displaying distinct abundance patterns. Notably, an increase in Actinomycedota in the endosphere correlated with a reduction in Pseudomonadota. The most significant shifts in microbial community composition occurred in the rhizosphere during the flowering stage, primarily driven by the genus Pseudomonas. These findings demonstrate that plant developmental stages and domestication influence the recruitment of specific microbial taxa to meet the plant’s needs, particularly in various root compartments. This selective recruitment highlights the active role of plants in shaping their microbiomes, providing insights into the potential for manipulating these communities to enhance crop productivity sustainably.ConclusionOur results indicate that both the host developmental stage and domestication significantly influence the assembly and structure of the plant microbiome. Plant root compartments can selectively recruit specific taxa from associated core microbial communities to meet their needs, depending on the plant’s developmental stage and the particular root compartment involved. These findings demonstrate that the deterministic selection pressures exerted by plants during their growth and development greatly affect their microbial communities. This has important implications for developing sustainable farming practices, reducing reliance on chemical fertilizers and pesticides, and enhancing future crop productivity
Assessing phenotypic and genotypic antibiotic resistance in bacillus-related bacteria isolated from biogas digestates
Full text linkAntibiotic resistance poses a significant public health challenge, with biogas digestate, a byproduct of anaerobic digestion (AD), presenting potential risks when applied as a biofertilizer. Understanding the actual resistance levels in digestate is crucial for its safe application. While many studies have investigated antibiotic resistance in AD processes using culture-independent molecular methods, these approaches are limited by their reliance on reference databases and inability to account for gene expression, leading to potential inaccuracies in resistance assessment. This study addresses these limitations by combining culture-independent whole-genome sequencing (WGS) with culture-dependent phenotypic testing to provide a more accurate understanding of antibiotic resistance in digestate. We investigated the phenotypic and genotypic resistance profiles of 18 antibiotic-resistant bacteria (ARB) isolated from digestates produced from food waste and animal manure. Resistance was assessed using WGS and Estrip testing across 12 antibiotics from multiple classes. This is the first study to directly compare phenotypic and genotypic resistance in bacteria isolated from digestate, revealing significant discrepancies between the two methods. Approximately 30 % of resistance levels were misinterpreted when relying solely on culture-independent methods, with both over- and underestimation observed. These findings highlight the necessity of integrating both methods for reliable resistance assessments. Additionally, our WGS analysis indicated low potential for transferability of detected ARGs among the isolated ARB, suggesting a limited risk of environmental dissemination. This study provides new insights into antibiotic resistance in digestate and underscores the importance of integrating methodological approaches to achieve accurate evaluations of resistance risks
Structure and Composition of a Selectively Logged Miombo Woodland in Central Mozambique
Full text linkThis study assessed the structure and composition of a Miombo woodland stand subjected to selective logging through a forest inventory, measuring all trees with DBH >= 10 cm across 34 plots (1 ha each) for diameter, height, stem quality, and health status. The stand had a mean stem density of 255 stems/ha, basal area of 15 m2/ha, above ground biomass of 110 Mg/ha, and total volume of 145 m3/ha. The Fabaceae family, particularly Brachystegia spiciformis, dominated the composition. Diversity indices revealed moderate diversity (Shannon = 2.3, Simpson = 0.8, Pielou = 0.6), with a few dominant species. The diameter distribution followed a reverse J-shaped pattern typical of Miombo woodlands. The study (LevasFlor. (2024). Plano De Maneio Da LevasFlor, LDA) highlighted common features of selectively logged woodlands, including a low occurrence of large-diameter individuals from high-value commercial species, prevalence of disturbance-tolerant species, and limited regeneration for some species. These findings underscore the need for management strategies that balance ecological and socio-economic factors, mitigate logging impacts, promote regeneration, and ensure long-term sustainability. Effective policies are crucial for maintaining the ecological integrity and economic value of Miombo woodlands while addressing climate resilience and biodiversity conservation