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‘specleanr’: an R package for automated flagging of environmental outliers in ecological data for modeling workflows
No full textDeveloping species distribution models (SDMs) requires high‐quality species occurrence records. These records, stemming from various sources with different sampling procedures, are often archived in open‐access databases, making automated data quality checks inevitable. Temporal, geographic, and taxonomic quality checks are usually conducted in SDM workflows, but checking for records distant in environmental space, i.e. outliers, is often ignored.
Here, we present ‘specleanr', an R package that contains 20 outlier detection methods (ODMs) that can be ensembled to identify potential outliers in environmental predictors. These methods are categorized into 1) species‐specific ecological range, 2) univariate, and 3) multivariate ODMs. All potential outliers flagged by the different methods are pooled to identify absolute outliers (records appearing in multiple methods). The local regression (LOESS) method is then used to automatically set a threshold that optimally identifies the absolute outliers. Additionally, clustering records into poor, fair, moderate, very strong, and perfect outliers, as well as non‐outliers, is possible based on each record's likelihood as a potential outlier, which allows expert assessment.
We demonstrated the approach to 15 fish species from the Danube River Basin, including native, alien, threatened, and common species. We fitted SDMs using bioclimatic and hydromorphological parameters. We compared the model area under the curve (AUC) before and after outlier removal using three scenarios: 1) the LOESS method, 2) removing very strong outliers, and 3) removing perfect outliers. The results showed a significant improvement in the model AUC, with generally small to moderate effect sizes after outlier removal.
‘specleanr' is generalizable across taxonomic groups, data types, ecological realms, and geographic regions. Beyond SDMs, it can also be broadly used in general data analysis where outlier detection is essential. We provide detailed vignettes to support package use. ‘specleanr' offers a user‐friendly and reproducible approach for handling outliers in biogeographical modeling and general data analysis workflows
Risks and Implications of Artificial Intelligence Usage
No full textAt the time of conflicts flaring up in different parts of the world, the potential and actual dangers caused by the developed artificial intelligence (AI) are also a worrying factor. AI is a technology that comes with serious and hard-to-predict risks for which society is not sufficiently prepared. This paper delves into the entangled aspects of the problem, such as the theological and sociological ones. Such a discourse overcomes technological determinism with the aim of revealing directions for deeper ontological and epistemological research. Relying on such insights, the paper examines the ethical implications of the artificial intelligence potential to challenge the fundamental principles of human being. Social disturbances and transformations caused by the pervasive influence of artificial intelligence on work, management and interpersonal dynamics are analyzed. The merger of religious and sociological discourse is emphasized, and also the designing of holistic understanding of moral imperatives and social limitations that should be a part of the artificial intelligence mastery
Doubling genome size of energy willow affects woody stem cell wall structure, chemistry, and biogas yield
No full textEffectiveness in woody biomass utilization is highly dependent on its genetics and
physiology. We performed morpho-anatomical, chemical, and biomethane productivity
characterizations of one-year-old woody stems in three shrub Salix viminalis
genotypes: a diploid (Energo) and its two autotetraploid derivatives (PP-E7 and
PP-E13). Tetraploidization affected changes in stem morpho-anatomy and corresponding
improved chemical features and biomethane productivity, considerably
more pronounced in tetraploid PP-E13, while PP-E7 was more similar to diploid
Energo. Compared to diploid Energo, in tetraploid PP-E13 morphometric analysis
showed increased stem diameter and higher wood fiber radial double wall thickness,
while microscopic analysis suggested higher syringyl to guaiacyl (S:G) ratio
of the wood fiber cell wall. Presented changes in stem morpho-anatomy of tetraploid
PP-E13 compared to diploid Energo correspond to the improved chemical features:
the lower Klason lignin content and higher S:G ratio, the higher cellulose and xylan
content, and lower cellulose crystallinity (Crl). Presented improved chemical features,
along with the increase in ash content, resulted in a 7.3% (10.3 CH4
mL/g
VS) increase in biomethane productivity in tetraploid PP-E13, compared to diploid
Energo, suggesting tetraploid PP-E13 as an optimal raw material for fermentation
technologies. In addition, besides the well-known chemical markers of willow biomass
quality, the presented results highlight key stem morpho-anatomical parameters,
which can serve as additional markers in energy willow improvement
Recycling and reuse potential of waste materials in cement and concrete industry and their environmental impact
No full textCement and concrete producers are under growing pressure to reduce greenhouse gas emissions and energy use in their processes. Some of the most widely implemented and practiced measures taken to tackle these demands are increased level of clinker substitution in cements and decreased content of cement in concrete and mortars.
Typical supplementary cementitious materials (SCMs) used in cement and concrete are ground granulated blast furnace slag (GGBFS) and fly ash (FA). Since these materials are byproducts of other industries, use of GGBFS and FA in cement and concrete has multiple benefits. Even more, over the past few decades, it has been demonstrated that GGBFS and FA can be used as raw materials for production of novel binders, such as alkali activated materials, with properties similar to traditional cements. Nevertheless, bearing in mind that GGBFS and especially FA, which is produced by coal fired power plants, are coming from the industries that are transitioning, there are reasonable global concerns about future availability of these SCMs.
On the other hand, construction and demolition waste (CDW) has been recognized as growing global challenge. It is estimated that CDW contributes to 30 – 50 % of the total solid waste generated worldwide. CDW generally consists of several waste types, such as concrete, timber, ceramics, metals, plastics and soils. Current research efforts are focused mostly on the properties and potential application of the recycled concrete aggregate and fines. Some recent studies demonstrated that enforced carbonation of recycled concrete aggregate and fines can lead to circular utilization of these waste materials in cement and concrete, with significant additional opportunity for CO2 sequestration. However, as composition of CDW is complex and highly variable, optimal recycling procedure and reuse potential of CDW are subjects of further ongoing research
Procedura korektnog određivanja parametara reakcije izdvajanja vodonika na elektrodi od Ni pene modifikovane elektrohemijski istaloženom Ni-Sn legurom
No full textThe example of the procedure for the correct determination of the parameters of hydrogen evolution reaction (HER), the exchange current density (jo) and relaxation time (to) for intermediate (adsorbed hydrogen, Hads) adsorption at modified porous Ni-based electrode are presented in this work. Such a procedure is applicable for the HER at all electrode materials. The value of jo was obtained from the intercept at h = 0 mV from the h vs. log (Rct-1) dependence (h – overpotential), while the value of to was obtained from the intercept at h = 0 mV from the logt vs. h dependence. It was shown that for the correct determination of jo and to, it is necessary to correct applied h for the jRs drop, by recording current density (j) for applied h and correcting it for jRs.Na primeru izdvajanja vodonika na Ni-Sn/Ni pena 800 elektrodi u ovom radu je prikazana procedura korektnog određivanja parametara ove reakcije, a to su: gustina struje izmene (jo) i relaksaciono vreme adsorpcije intermedijara (t) (Hads). Vrednost jo je određena iz odsečka za h = 0 mV zavisnosti h vs. log(Rct-1) (h – prenapetost), dok je vrednost to određena iz odsečka za h = 0 mV zavisnosti logt vs. h. Pokazano je da je za korektno određivanje ovih parametara neophodno korigovati gustinu struje pri svakoj zadatoj prenapetosti za vrednost omskog pada napona jRs
SILICON AND IRON IN FOOD CROPS: IMPACT ON HUMAN HEALTH
No full textSilicon (Si) and iron (Fe) are the second and fourth most abundant elements in the Earth's crust, respectively. The essentiality of Fe was recognized in the mid-19th century, yet essentiality of Si for both higher plants and humans is not fully accepted. Silicon serves as a beneficial mineral for plants, enhancing their resilience to biotic (diseases and pests) and abiotic (drought, low pH, salinity, nutrient disbalances, etc.) stresses. The beneficial effects of Si for human health, including contributions to bone and collagen development and the prevention of Alzheimer's disease, have also been well established. Approximately one-third of global agricultural soils are conductive to Fe-deficiency in various crops, leading to anemia in over two billion world population. To improve content of Si and Fe in edible plant parts (biofortification), two primary strategies are proposed: (1) increasing soil bioavailability of both minerals alongside the use of Si/Fe-based fertilizers, and (2) improving the nutritional quality of plant-derived foods through molecular breeding techniques to modify the content of Si and Fe in crops. We revealed that Si supplementation in crops can promote the root acquisition of Fe and enhance its phloem transport to the edible crop parts. Our recent results demonstrate the ability of Fe-deficient crops to increase Si availability in the rhizosphere, which, in turn, enhances the uptake and transport of both minerals. This opens new innovative approaches in crop Si/Fe biofortification practices for improved human health
Root exudates mobilize silicon (Si) from different soil Si-pools
No full textThe availability of soil silicon (Si) to plants is often limited because most Si is bound to primary
(e.g., feldspar) and clay minerals or exists in forms such as amorphous SiO2 (e.g., plant phytoliths)
and crystalline SiO2 (e.g., quartz). Enhanced root exudation of low-molecular-weight (LMW)
compounds is a common plant adaptation to low-nutrient environments. Recently, it has been
proposed that root-released carboxylates also mobilize soil Si. However, the impact of LMW root
exudates, beyond carboxylates, on increasing the availability of Si in the rhizosphere remains unclear.
To test the Si-mobilizing potential of root exudates, we conducted a series of experiments.
Cucumber and barley were subjected to iron (Fe) and zinc (Zn) deficiency, respectively, to induce
enhanced root exudation. The root exudates were collected over time, and the solutions mainly
containing carboxylates and riboflavin (Fe-deficient cucumber) and carboxylates and phytosiderophores
(Zn-deficient barley) were used for extraction of four soils differing in pH value and clay
content. Additionally, we tested the potential of root exudates to mobilize Si from two different
forms of SiO2, i.e., phytoliths and quartz, which, along with silicon minerals, represent major soil
Si pools. Our results indicate that root exudates have a high potential to mobilize Si, primarily
depending on soil clay content and pH. Additionally, the root exudates enhance the solubility of
amorphous SiO2, especially from phytoliths. Besides the high Si-mobilizing potential of carboxylates,
both riboflavin and phytosiderophores contribute to Si mobilization. This was further confirmed
by in vitro experiment using individual components of the root exudates
Soybean increases grain Zn and protein of winter wheat grown in the three-crop rotation
No full textCrop rotation systems provide various benefits to sustainable agriculture. The inclusion of legume
crops in rotation enhances the nutrient cycle in the soil-plant system, and especially the nitrogen (N) nutritional status of wheat. On the other side, N is involved in increased zinc (Zn) deposition in grains. Therefore, it is hypothesized that the inclusion of soybean in cereal-cereal rotation (e.g. maize–winter wheat) can increase both Zn and protein contents in wheat grains. The study was conducted at the experimental site in Rimski Šančevi, Serbia, as a part of a long-term crop rotations field trial established on a Chernozem in 1946. The trial included maize–winter wheat and maize–soybean–winter wheat crop rotations. To our best knowledge both cropping systems didn’t receive fertilization since the beginning of a long-term trial. Bread winter wheat cv. Zvezdana was harvested in 2022. Wheat plots of both crop rotation systems were split into three subplots, and each represented one replication. Results of the t-test revealed that grain yield in three-crop rotation of 2.12 t ha-1 was significantly higher than 1.10 t ha-1 obtained in maize–winter wheat rotation, as well as grain Zn concentration (24.8 mg kg-1 and 20.6 mg kg-1, respectively) and grain protein (10.8% and 9.7%, respectively). Our results indicate the high potential of soybean to increase Zn and protein content in wheat grain under long-term conditions without NPK fertilization
Silicon nanoparticles in sustainable agriculture: synthesis, absorption, and plant stress alleviation
Get PDFSilicon (Si) is a widely recognized beneficial element in plants. With the emergence of nanotechnology in agriculture, silicon nanoparticles (SiNPs) demonstrate promising applicability in sustainable agriculture. Particularly, the application of SiNPs has proven to be a high-efficiency and cost-effective strategy for protecting plant against various biotic and abiotic stresses such as insect pests, pathogen diseases, metal stress, drought stress, and salt stress. To date, rapid progress has been made in unveiling the multiple functions and related mechanisms of SiNPs in promoting the sustainability of agricultural production in the recent decade, while a comprehensive summary is still lacking. Here, the review provides an up-to-date overview of the synthesis, uptake and translocation, and application of SiNPs in alleviating stresses aiming for the reasonable usage of SiNPs in nano-enabled agriculture. The major points are listed as following: (1) SiNPs can be synthesized by using physical, chemical, and biological (green synthesis) approaches, while green synthesis using agricultural wastes as raw materials is more suitable for large-scale production and recycling agriculture. (2) The uptake and translocation of SiNPs in plants differs significantly from that of Si, which is determined by plant factors and the properties of SiNPs. (3) Under stressful conditions, SiNPs can regulate plant stress acclimation at morphological, physiological, and molecular levels as growth stimulator; as well as deliver pesticides and plant growth regulating chemicals as nanocarrier, thereby enhancing plant growth and yield. (4) Several key issues deserve further investigation including effective approaches of SiNPs synthesis and modification, molecular basis of SiNPs-induced plant stress resistance, and systematic effects of SiNPs on agricultural ecosystem
The Effect of Biotic Stress in Plant Species Induced by ‘Candidatus Phytoplasma solani’—An Artificial Neural Network Approach
Get PDFInfections with phytoplasma present one of the most significant biotic stresses influencing
plant health, growth, and production. The phytoplasma ‘Candidatus Phytoplasma solani’ infects
a variety of plant species. This pathogen impacts the physiological and morphological characteristics of plants causing stunting, yellowing, leaf curling, and other symptoms that can lead to significant economic losses. The aim of this study was to determine biochemical changes in peony (Paeonia tenuifolia L.), mint (Mentha × piperita L.), and dill (Anethum graveolens L.) induced by ‘Ca. Phytoplasma solani’ in Serbia as well as to predict the impact of the biotic stress using artificial neural network (ANN) modeling. The phylogenetic position of the Serbian ‘Ca. Phytoplasma solani’ strains originated from the tested hosts using 16S rRNA (peony and carrot strains) and plsC (mint and dill strains) sequences indicated by their genetic homogeneity despite the host of origin. Biochemical parameters significantly differed in asymptomatic and symptomatic plants, except for total anthocyanidins contents in dill and the capacity of peony and mint extracts to neutralize superoxide anions and hydroxyl radicals, respectively. Principal Component Analysis (PCA) showed a correlation between different chemical parameters and revealed a clear separation among the samples. Based on the ANN performance, the optimal number of hidden neurons for the calculation of TS, RG, PAL, LP, NBT, •OH, TP, TT, Tflav, Tpro, Tant, DPPH, and Car was nine (using MLP 8-9-13), as it produced high r2 values (1.000 during the training period) and low SOS values. Developing an effective early warning system for the detection of plant diseases in different plant species is critical for improving crop yield and quality