Beginning Of Spring Research Articles

Low-Temperature Regulates the Cell Structure and Chlorophyll in Addition to Cellulose Metabolism of Postharvest Red Toona sinensis Buds across Different Seasons.

Postharvest fibrosis and greening of Toona sinensis buds significantly affect their quality during storage. This study aimed to clarify the effects of low-temperature storage on postharvest red TSB quality harvested in different seasons. Red TSB samples were collected from Guizhou province, China, 21 days after the beginning of spring (Lichun), summer (Lixia), and autumn (Liqiu), and stored at 4 °C in dark conditions. We compared and analyzed the appearance, microstructure, chlorophyll and cellulose content, and expression levels of related genes across different seasons. The results indicated that TSB harvested in spring had a bright, purple-red color, whereas those harvested in summer and autumn were green. All samples lost water and darkened after 1 day of storage. Severe greening occurred in spring-harvested TSB within 3 days, a phenomenon not observed in summer and autumn samples. Microstructural analysis revealed that the cells in the palisade and spongy tissues of spring and autumn TSB settled closely during storage, while summer TSB cells remained loosely aligned. Xylem cells were smallest in spring-harvested TSB and largest in autumn. Prolonged storage led to thickening of the secondary cell walls and pith cell autolysis in the petioles, enlarging the cavity area. Chlorophyll content was higher in leaves than in petioles, while cellulose content was lower in petioles across all seasons. Both chlorophyll and cellulose content increased with storage time. Gene expression analysis showed season-dependent variations and significant increases in the expression of over half of the chlorophyll-related and cellulose-related genes during refrigeration, correlating with the observed changes in chlorophyll and cellulose content. This research provides valuable insights for improving postharvest storage and freshness preservation strategies for red TSB across different seasons.

A Just Englishman in Russia: The Ethical Self in Penelope Fitzgerald’s The Beginning of Spring

ABSTRACT In her historical novel, The Beginning of Spring, Penelope Fitzgerald explores English identity in pre-revolutionary Russia by putting her expatriate hero Frank Reid to the test in ethical situations. Engaging with critical attention to the novel’s moral meaning, this article offers an ethical reading alongside Paul Ricoeur’s study on ethical intention and Emmanuel Levinas’s ethics of the face of the other. Frank’s ethical self can be imputed from his aim of becoming a just man in the Moscow business community. To achieve that aim, he must make ethical deliberations based on his practical wisdom and the moral injunction that regulates the intersubjective relationship between the self and the other. He ultimately fails his ethical aim because of the unjust institution – he is othered in/by Russia. I conclude with a gesture that the novel is Fitzgerald’s ethical intention of giving a voice to the other Russian culture.

The influence of environmental change and seasons on the sperm quality of breeding boars after relocation

This study aimed to determine the impact of relocation as a potential stress factor on the reproductive properties of breeding boars, as well as the impact of the new environment on the quantity and quality of the semen obtained during different seasons. At the beginning of spring, 16 breeding boars (Large White (n=3), German Landrace (n=4), Swedish Landrace (n=6) and Pietrain (n=3)) were relocated from old to new housing conditions and exposed to loading, transport, unloading, and rehousing in a new environment. They had the same conditions of feeding, care, sexual exploitation and keeping, before and after relocation. The health status of all breeding boars was carefully monitored and controlled. No significant differences were observed in the total and average number of doses produced between seasons. There was a significantly higher value of total ejaculate volume and density during the spring compared to the values obtained in other seasons (P<0.01). Differences in the average percentage of mobility between autumn and winter were not significant (P=0.983), as in spring and summer (P=0.737). Ventilation rate, gas concentrations of ammonia, nitrous oxide and carbon dioxide in the boar enclosure were similar before and after relocation. Two days after relocation, one boar (ID 172) showed signs of illness and was treated, but his sperm was rejected due to sperm agglutination and reduced motility, so he was culled. Individual analysis of the production indicators showed that there was no significant change in the spermatogenesis of healthy boars, even though they were relocated.

Vitamin D and behavioral disorders in older adults: results from the CLIP study

ObjectivesVitamin D is involved in brain health and function. Our objective was to determine whether vitamin D deficiency was associated with behavioral disorders in geriatric patients. DesignThe observational cross-sectional CLIP (Cognition and LIPophilic vitamins) study. The report followed the STROBE statement. SettingGeriatric acute care unit in a tertiary university hospital in France for 3 months at the end of winter and beginning of spring. Participants272 patients ≥65 years consecutively hospitalized or seen in consultation. MeasurementsParticipants were separated into two groups according to vitamin D deficiency (i.e., serum 25-hydroxyvitamin D ≤25 nmol/L). Behavior was assessed using the reduced version of the Neuropsychiatric Inventory Scale (NPI-R) score and subscores. Age, sex, BMI, education level, comorbidities, MMSE and GDS scores, use psychoactive drugs and vitamin D supplements, and serum concentrations of calcium, parathyroid hormone, TSH and estimated glomerular filtration rate (eGFR) were used as potential confounders. ResultsParticipants with vitamin D deficiency (n = 78) had similar NPI-R score (17.4 ± 20.3 versus 17.2 ± 16.1, p = 0.92) but higher (i.e., worse) subscore of agitation and aggressiveness (2.0 ± 3.3 versus 1.2 ± 2.4, p = 0.02) and higher (i.e., worse) subscore of disinhibition (0.99 ± 2.98 versus 0.38 ± 1.42, p = 0.02) than those without vitamin D deficiency (n = 194). In multiple linear regressions, vitamin D deficiency was inversely associated with the subscore of agitation and aggressiveness (β = 1.37, p = 0.005) and with the subscore of disinhibition (β = 0.96, p = 0.008). ConclusionVitamin D deficiency was associated with more severe subscores of agitation and aggressiveness and of disinhibition among older adults. This provides a scientific basis to test the efficacy of vitamin D supplementation on behavioral disorders in older patients with vitamin D deficiency.

The history of fire, human and climate in black pine forests of western Anatolia: The Taurus mountains

The interactions between fire occurrence-human-climate are highly complex to understand and also difficult to predict due to having many sources of variations in fire regimes. However, we can gather information about the effect of human influence on the regional fire regimes where human influence is high, and the history of locations is well-known by conducting retrospective fire history studies in locations. Here, we present the impact of human settlements on fire occurrence by comparing and discussing the previous drought-driven tree-ring-based fire history reconstruction sites in western Anatolia. For this purpose, we collected cross-sections from Miyarcık highland, Antalya, and developed a 519–y long (1503–2021 CE) composite fire chronology using dendrochronological methods. Our study site location is known for the seasonal inhabitants of “Yörüks”, who led a nomadic life in the Taurus Mountains for centuries, and forests were used for livestock grazing. Since the temperatures increase significantly at the beginning of spring in the lower elevations of Antalya, the yörüks move towards the upper highlands with their animals from May to November. We found lower fire frequency and no fire-climate association compared to other sites that experienced drought-driven wildfires, even though this site is located in a high-fire-risk region. Low-frequency fires might be due to moderate-level livestock grazing by yörüks in this area. Grazing contributes to reducing the amount of accumulated combustible materials, causes discontinuity of fuel in the understory of forests, and affects the dynamics of the spatial distribution of wildfires. This study showed that moderate-level grazing might support effective fire management activities as fuel management because of modifying the fuel properties, changing the fuel-fire interaction (e.g., the fuel continuity and amount of accumulated fuel), and reducing the wildfire probability over space and time.

Effect Exercised by Climate on the Taxonomic Diversity of Vascular Plants in the Middle Volga Region

Analysis of relationships between the richness of three taxonomic ranks of vascular plants in the Middle Volga region and climate showed that the climatic factor explains 74% of variance in the number of species and families and 76% of variance in the number of genera. Taxonomic parameters of a floristic sample collected on 25 polygons 100 km2 in size each were compared with climatic parameters and their functions. Multiple regression models were produced for the three taxonomic ranks (numbers of families, genera, and species), and maps have been constructed on the basis of these models. The main predictors were climatic parameters at the beginning of spring and in winter months. Statistically significant correlations between the richness of species, genera, and families and some functions of climatic parameters that are usually excluded from analysis were identified. The essence of these functions is discussed in the context of their effect on snow melting processes in early spring.

Chemical Composition and Insecticidal Activity of Thymus algeriensis Boiss and Reut. Essential Oil against Aphis fabae Scopoli1763

Background: The aim of the present work was to study the chemical composition and evaluate the insecticidal activity of Thymus algeriensis Boiss and Reut. essential oil (TAEO) against Aphis fabae Scopoli is a polyphafous which desap many cultivated plants, under shelter and in the open field. Methods: The extraction of essential oil from the aerial parts of T. algeriensis was performed by hydro-distillation (yield: 2.7% w/w). The extracted essential oil was analyzed by gas chromatography coupled with mass spectrometry (GC/MS) and by gas chromatography (GC). Result: From this essential oil 22 compounds representing 92.27% of the oil were identified. The main constituents were carvacrol (61.5%), g-terpinene (8.81%) and p-cymene (10.83%). The experiment was carried out in random blocks (05), to study the behavior of Aphis fabae and its host, namely Vicia fabae. Thus, twenty-five bean plants infested with black aphids were chosen and distributed at random. The plants were treated by spraying at different doses of (HETA) (control, acetone; 0.1; 0.05 and 0.01%). The results obtained showed that TAEO at 0.1% results in a decrease of infestation rate of A. fabae, leading a mortality rate of 75.51%.The results of the treatment carried out at the beginning of spring are very promising; oil could thus be used as bio-insecticide.

Rising global incidence of invasive group A streptococcus infection and scarlet fever in the COVID-19 era – our knowledge thus far

Rising global incidence of invasive group A streptococcus infection and scarlet fever in the COVID-19 era – our knowledge thus far

Agrometeorological water balance in the west of São Paulo State

The agriculture economic viability is a result of a correct planning and knowledge of the crop production environment. The level of meteorological information in the region can be improved through the water balance, making the agricultural planning more accurate. The objective of this study was to characterize the West of the São Paulo State through the agrometeorological water balance. Historical daily data from 1992 to 2021, from the meteorological station of the University of West Paulista in Presidente Prudente, São Paulo, were used in the study. The sequential water balance (deficit and excess of water in the soil) was evaluated during the agricultural season (from October to March) and off-season (from April to September). The annual water deficit was -303.2 mm, being -125.2 mm in the agricultural season and -178.0 mm in the off-season. The frequent occurrence of deficit in the region, in the beginning of spring and mainly during the autumn-winter, makes it necessary to adopt special management practices and to use irrigation in order to reach high agricultural productivity in West Paulista.

Phytochemical characterization and antioxidant potential of Allium ursinum L. cultivated on different soil types- a preliminary study

Wild garlic (Allium ursinum L.) has been used as nutrition and medicine for centuries. Although this plant species is a typical springgeophyte that grows spontaneously in moist, steep, shady beech forests, but information on phytochemical and antioxidant propertiesunder various soil types are scarce. This study aimed to assess the phytochemical composition and antioxidant potential of the leaves ofA. ursinum grown on different soil types, but under identical climatic conditions of South Banat, Serbia. For the purpose of reproduction,A. ursinum bulbs were collected from two different locations in Serbia and then planted on different types of soil, namely: Arenosol,Fluvisol, Cambisol and Chernozem. Fresh leaves of sprouted plants were sampled at the beginning of spring, morphologically analysedand stoma was counted. The leaf extract was prepared and its phytochemical composition and antioxidant potential were assessed.Regardless of the origin of the reproductive material (bulbs), the leaves of A. ursinum plants cultivated in Chernozem soil had the bestmorphological characteristics and the largest number of stomata. Phytochemical analyses revealed the following ranges for selectedbioactive compounds (expressed on fresh weight, FW): chlorophyll content (289.9-642.4 μg/g for chlorophyll a i.e. 358.2-458.6 μg/gfor chlorophyll b), total carotenoid content (TCC, 91.2-263.2 μg/g), total phenolic content (TPC, 1.43-1.98 mg/g GAE), total flavonoidcontent (TFC, 0.36-1.28 mg/g QE), and total dihydroxycinnamic acid derivative content (HCA, 0.53-0.59 mg/g CGAE). The highestvalues were obtained on Chernozem (chlorophyll a, chlorophyll b and TPC and HCA) and Cambisol (TCC and TFC). Chernozem appearedto be the best soil type during three applied standard antioxidant assays (CUPRAC, TAC and FRP) while DPPH radical quenching assayrevealed no significant differences among all examined soil types. Based on the obtained results it could be assumed that Chernozemexhibited the most desirable physico-chemical properties for optimal development of A. ursinum (in particular its green parts) as a sourceof different antioxidants. Correlation analysis of phytochemical parameters has proved significant influence of total chlorophylls, phenolics,flavonoids and duhydroxycinnamic acid derivatives on antioxidant activity of A. ursinum leaves (unlike total carotenoid content) with thehighest correlation between HCA and FRP assay (r2= 1.00). In addition, PCA analysis clearly determined Chernozem type of soil as thebest choice for optimal leaf growth and development.Keywords: Wild garlic; cultivation; morphology; leaves; phytochemicals

A Study of Ecological Metaphors in the Winter Olympic Games’ Promotional Film “Countdown: Beginning of Spring”

A Study of Ecological Metaphors in the Winter Olympic Games’ Promotional Film “Countdown: Beginning of Spring”

Временная изменчивость городского острова тепла Екатеринбурга

The article deals with the analysis of temporal variability of the urban heat island (UHI) in the field of surface air temperatures in Yekaterinburg using the data on meteorological observations on weather stations “Yekaterinburg” and “Verkhnee Dubrovo”. The UHI intensity variations have been analyzed for the periods from annual/interannual to diurnal. The sustainable effect of the urban heat island is manifested in all seasons. Annual cycles of monthly averaged UHI values demonstrates “W”-shaped form with maxima of about 1.0 ºС in February/March and in three summer months. Summer maximum is generally determined by maximal diurnal (night) UHI values. The maximum in February/March is related to the increased minimum daily values. From the 50s of the 20th century “W”-shaped annual curve of the UHI intensity remained unchanged under the increase in mean annual UHI values while growing at a rate of 1.31 ºС/100 years to the beginning of the 80s. At the same time, summer maximum increased at a faster rate in comparison with the winter one. Since the beginning of the 80s, the mean annual UHI intensity has stabilized at the level of 0.8 ºС. In a diurnal cycle, the maximal UHI intensity (to 2.4 ºС) is observed in May-July after the sunset. Maximal daily UHI intensity values in summer months are associated with a slower cooling of the city in high-rise building area. The local afternoon maximum (up to 0.8 ºС) caused by the insolation maximum under low albedo value of the urban coverage occurs also from May to July. In the autumn-winter period and at the beginning of spring, the daily amplitude of the UHI intensity decreases due to a decrease in the maximum of UHI and a slight increase in the minimum one. The increase in the minimum UHI values is facilitated by cloudiness, snow cover, calm wind conditions, an increase in the concentration of aerosol and water vapor near the surface and anthropogenic heat emissions. The study results can be used in fundamental and applied climatology, in the development of urban policy.

Картографирование динамики лесов севера Московской области по спутниковым снимкам серии Landsat

Solving the problem of identifying areal and formational changes in forests is an urgent problem in studying the dynamics of forest cover [Coppin, 2004; Senf et al., 2017]. The presented study is devoted to identifying the spatiotemporal variability of forest cover in the Moscow Region using the example of the Klinskiy district (Fig. 1). As part of this work, the problem of a methodological approach to identifying changes in the composition of forests was solved and changes in the formational composition of forests in the study area were established. The work used 153 geobotanical relevés made between 2013 and 2021, satellite images of Landsat-8 (2014–2021) and Landsat-5 (1985–1986), a digital elevation model and forest plans. The work scheme includes 5 stages (Fig. 2): 1) data collection in GIS; 2) classification of communities, development of legends for maps of the forest’s formational composition; 3) processing of satellite images; 4) automated classification of multi-temporal composites with the formation of a training sample; 5) analysis of changes. For the analyzed periods 1985–1986 and 2014–2021 cloudless satellite images were selected for the beginning, middle and end of the growing season, as well as the end of winter and beginning of spring (Table 1). For them, the vegetation indices NDVI, EVI and NDMI were calculated, pruning was carried out according to the forest mask, and subsequently the materials were combined into composites. Classification of prepared composite images for 1985–1986 and 2014–2021 was carried out using discriminant analysis method with a training sample prepared according to available relevés and forest plans. This made it possible to establish with sufficiently high accuracy the formation composition of forests at the dates of the period under study: 1985–1986 and 2014–2021, the accuracy of the determination was 79.3 % and 78.8 % (Table 2). A similar technique for selecting satellite images was used previously for mapping the current state of forests in the Moscow region [Chernenkova et al., 2019; Kotlov, Chernenkova, 2020]. As a result, maps of the formational composition of forests for the indicated periods were obtained, and an analysis of changes was carried out. The identified changes show a relatively small decrease in the total forested area from 55.1 % to 52.1 %. The composition of forests has changed significantly; only 26 % of forests have not changed their formational affiliation, of which the pine formation is the most stable (82.6 % have not changed their formational affiliation). A general increase in the share of birch and aspen formations was revealed at the present stage compared to 1985–1986, and it can be assumed that, despite a slight change in the total forested area of the region (from 55.1 % to 52.1 %), the composition of forests is becoming more disturbed (Table 4). As a result of the work, a methodology was tested for identifying formational changes in the forests based on the use of multi-temporal satellite images of the Landsat series. The territorial and qualitative changes in the forest cover of the study area have been established. The presented methodology has prospects for testing not only in the Moscow Region, but also in other regions.

Microplastics in the first-year sea ice of the Novik Bay, Sea of Japan.

Sea ice is heavily contaminated with microplastics particles (MPs, <5mm). First-year sea ice cores (38-41cm thick) were taken in the beginning of spring in a narrow populated bay of the Sea of Japan. Two ice cores were examined (layer-by-layer, excluding surface) for MPs content: one using μ-FTIR for 25-300μm (SMPs), and another one - with visual+Raman identification for 300-5000μm particles (LMPs). The integral (25-5000μm) bulk mean abundance of MPs was found to be 428 items/L of meltwater, with fibers making 19% in SMPs size range and 59% in LMPs. Integral mean mass of MPs was estimated in 34.6mg/L, with 99.6% contribution from fragments of LMPs. Comparison with simple fragmentation models confirms deficit of SMPs (especially of fibers in size range 150-300μm), suggested to result from their leakage with brine. Multivariate statistical analysis indicates strong positive correlation of large fiber (>300μm) counts and ice salinity.

Recruitment of the endangered limpet Patella ferruginea in the Chafarinas Islands (SW Mediterranean)

AbstractThe recruitment of the endangered limpet Patella ferruginea in the Chafarinas Islands (SW Mediterranean) was studied over a 17-year period (1999‒2015). A total of 8115 recruits &lt;20 mm in maximum diameter were counted in 95 transect censuses sampled during the study period. The presence of recruits began at the end of winter or beginning of spring (March‒April), when they reached a maximum shell diameter (MD) of at least 4 mm, with a peak in abundance occurring in spring. Smaller recruits were found on the lower midlittoral on the fringe of the vermetid gastropod Dendropoma lebeche and the crustose coralline algae Neogoniolithon brassica-florida, which suggests that settlement occurs at this shore level. Recruits reach 12‒27 mm at the end of their first year of life. A regular recruitment was detected for all studied years, with an average of 11.71 recruits m−1 across the study period. However, recruitment exhibited high interannual variability and did not occur evenly along the coastline of the islands. Higher recruitment was observed in 2001, 2011 and 2012, with a maximum density of 69.07 recruits m−1 in one transect in 2012. The density of recruits decreased in summer. No significant correlation was found between the density of recruits and adults. Between 1999‒2010, 29.29% of recruits were ‘phoretic’ on the shell of adults (1.81 recruits per host on average). Recruits climbed on to adults sometime after settlement, thus we suggest that ‘phoresy’ could favour the survival of young limpets instead of being due to selective settlement on adults. To improve and standardize recruitment monitoring in future studies, we propose that recruits are considered as those specimens &lt;20 mm in MD and that recruitment censuses are carried out in spring, with additional censuses after summer to detect juvenile mortality. Additionally, we propose that 1 mm interval size classes are used for growth studies based on size‒frequency analyses.

Case study on the effectiveness of Agrometeorological Proverbs

Many agrometeorological proverbs unique created by Chinese ancestors imply the relationship between universe, season, climate and agriculture events, which have been past considered as the valuable weather calendar to guide the agriculture events in China for thousands of years. And subject to the variation among various regions with distinguished climate or agricultural conditions, there is a requirement to examine the scientificity and applicability of agrometeorological proverbs before guiding the agriculture management. Based on the daily meteorological data of 206 meteorological stations in the Yangtze River Basin from 1966 to 2019, this paper explored the scientificity of meteorological knowledge embedded in meteorological proverbs “The Beginning of Spring at both ends resulting in hot in the dog days” and their applicability in the context of climate change. The study firstly investigated the warming rate based on the least-square method to fit the temperature data curves of the Beginning of Spring- Minor Heat in the Beginning of Spring at both Ends Years (BSEY) and Normal Years (NY), and to classify the “Fast Warming” (FW) temporal period according to the criteria that the days with a slope of warming of BSEY is greater than the slope of warming of NY in a certain temporal period, which accounts for more than 65% of the total number of days in the temporal period; Furthermore, the differences between BSEY and NY in the “Hot Dog Days ”(HDD) phase were compared and analyzed according to the inter-decadal precipitation and the different “ Heat levels” criteria defined by the difference of the Temperature-Humidity Index (THI) between the two years. Results shows that: (1) all regions in the Yangtze River basin, except for the plateau areas, are in line with the “FW” characteristic, accounting for 69% of the Yangtze River basin area, and the temporal period in which the “FW” characteristic appears (46 days after the Beginning of Spring) is before the the Spring Equinox. (2) There are areas in the upper, middle and lower reaches of the Yangtze River basin that meet the “HDD” characteristics, with the strongest compliance in the lower reaches, accounting for 90% of the lower reaches, and differences in the non-compliant areas, except for the Qinghai-Tibetan alpine region, mainly due to the influence of mountain ranges and other topography. In summary, the proverb is suitable for the main circulation regions in terms of applicability, and meteorological knowledge behind the proverb is also scientificity appropriate in the region where it is used. Meanwhile, this study can provide a reference for future policy development, agriculture-related research, and proper arrangement of agricultural production.

Forage characterization of Carajás grass (&lt;i&gt;Cenchrus purpureus&lt;/i&gt; × &lt;i&gt;C. americanus&lt;/i&gt;) fertilized with a range of doses of protected urea under irrigation during the growing season

The objective of this study was to assess the agronomic and nutritional responses of Carajás grass (Cenchrus purpureus × C. americanus, syn. Pennisetum purpureum × P. glaucum, cultivar ‘Carajás’) fertilized with protected urea. The experimental design was completely randomized blocks in split-plot arrangement over time. The treatments consisted of 5 levels of nitrogen (0, 100, 200, 400 and 800 kg N/ha/year) and measurements were made over 2 seasons (spring 2015 and summer 2016), with 8 replicates. Leaf and stem elongation and senescence rate of tillers increased as N dosage increased, while tiller density, leaf:stem ratio, live:dead material ratio and phyllochron declined. Forage biomass increased with N dosage reaching 47 t DM green forage/ha at 800 kg N/ha but DM production per unit of N applied declined dramatically as level of N applied increased. There was no effect of season. For crude protein (CP) and fiber concentrations, a positive effect was observed with increasing N application, with maximum CP% of 172 g/kg with 800 kg N/ha in spring. Further studies are warranted to determine if economics indicate that the higher fertilizer levels are justified and even protected urea should still be applied on a number of occasions, but still less often than conventional urea, rather than as a single dose at the beginning of spring.

Grass species litter have varied trait response to the photodegradation and microbial decomposition in tropical savanna grasslands, South Africa

Purpose of the paper: This paper evaluated the effects of microbial and photodegradation on the ten grass species in a tropical grassland ecosystem in South Africa. Despite continuous necromass accumulation in tropical grasslands, the process that governs how the grass litter gets to the soil has often been ignored. In the absence of fire, abiotic factors and biotic factors are drivers of this process of nutrient cycling. Methods and approaches: A classical litterbag experiment was set up to simulate photodegradation (standing litter) versus microbial (soil surface) decomposition using 10 savanna types of grass from the start of the dry season until the beginning of spring. The rates of photodegradation versus microbial decomposition were compared for tropical savanna grasses and plant traits or predictors of decomposition were also investigated. Main results: The results showed that the grass litter decomposed more rapidly when exposed to the activity of soil microbes at the soil surface (k = 0.0028 ) than when held above ground (k = 0.0018) and subjected to photodegradation only. However, examination of the individual litter species revealed up to 4 fold variation between the slowest (0.0001) and fastest (0.006) decomposing species. Differences in decomposition rates were more pronounced for litter decomposed at the soil surface than held above the soil surface. Multiple linear regression analyses did not resolve clear differences between measures of litter quality as drivers of decomposition in the two treatments. Implications: Photodegradation appeared to be a rate-controlling step during the process of decomposition in tropical savanna grasslands. Therefore grasslands dominated by photodegradation-resistant grasses were likely to need fire to get rid of moribund litter, which may be the reason why mesic grasslands need to burn to recycle nutrients.

Advancing understanding of in-river phosphorus dynamics using an advection–dispersion model (ADModel-P)

The objectives of the present research are (1) to predict phosphorus compounds transport along river stretches at high spatio-temporal resolution by developing an original approach based on advection–dispersion modelling (ADModel-P); (2) to advance the understanding of in-stream phosphorus transformation processes, and (3) to explore their relation to controlling factors (water temperature, seasonality and water flow). For a case study of the River Swale (UK) modelling results, in agreement with results based on experimental data, show that resuspension is the largest contributor to the variability of organic phosphorus, while adsorption–desorption are the largest contributors to the variability of soluble reactive phosphorus. Additionally, simulations reveal that conversion of inorganic to organic forms is important. In-channel sinks appear more important than sources for Soluble Reactive Phosphorus (SRP) during 80% of the time, while there is no clear evidence that Organic Phosphorus (OP) sinks or sources are dominant except the beginning of spring (around 20% of the total time). The findings are valuable because they advance knowledge regarding: (1) which in-stream processes are important; (2) values associated to transformation rates for mineralization, sedimentation, resuspension, uptake, adsorption – desorption; (3) at which times rivers are net sources or sinks and which source/sink processes might be dominant. ADModel-P is a robust model which has the benefits of simple field data requirements (compared to more complex models) and less assumptions (e.g. compared to simple models assuming perfect mixing in reaches) but without the drawbacks of lack of process representation to enable confidence in predictions to change. There is extensive scope for transferability to other rivers: rate constants can be estimated from easily attainable information on water temperature, seasonality and water flow.

Length-Weight Relationships and Otolith-Based Growth Curves for Brushtooth Lizardfish off Taiwan With Observations of Region and Aging–Material Effects on Global Growth Estimates

Establishing appropriate aging procedures and growth models are two important steps for estimating reliable growth curves and in developing proper stock assessments. Lizardfishes have a strong influence on the structures of epibenthic communities and are important to the trawl fisheries of many coastal countries. For brushtooth lizardfish, Saurida undosquamis, the major species in the lizardfish catches of Taiwan, three issues were investigated. First, we used generalized additive models to explore factors (e.g., sex, data source, season) affecting the length-weight relationship (LWR), and to estimate suitable parameters. Second, we identified suitable procedures for otolith preparation (sagittal or transverse sections), validated the periodicity of ring increments using marginal increment analysis (MIA) with discussions of the appropriateness of the analysis, and determined the “best-fit” growth model via multi-model inference. Lastly, we compared growth estimates from this study with those published globally and developed an overview of global variation and the main associated variables through hierarchical cluster analysis and random forest modeling. Results suggested the following. (1) A suitable LWR for the stock was BW = 6.269 × 10-3 · FL3.144 for females and BW = 6.439 × 10-3 · FL3.144 for males. The allometric coefficient varied among samples and data sources and through the season. (2) Aging precision may be higher using transverse sections rather than sagittal sections. MIA indicates that otolith ring marks are formed annually during the active spawning season at the end of winter and the beginning of spring (from February). The Von Bertalanffy Growth Model was selected and the parameters (L∞, K, and t0) were: 46.4 cm, 0.12 year-1, and -2.12 year for sex-combined; 38.6 cm, 0.15 year-1, -2.06 year for males; and, 42.0 cm, 0.16 year-1, -1.53 year for females. (3) Globally, 86 sets of growth parameters were compiled from the literature. Region and aging material were the most important sources of variation in global estimates, which indicates the importance of using reliable aging material.