Does stand age affect methane consumption of forest soil? A study in a chronosequence of sessile oak.

2020 ◽  
Author(s):  
Nicolas Bras ◽  
Caroline Plain ◽  
Daniel Epron
Keyword(s):  
Forest Soil ◽  
Late Summer ◽  
Total Porosity ◽  
Gas Diffusion ◽  
Early Spring ◽  
Stand Age ◽  
Atmospheric Methane ◽  
Tree Roots ◽  
Methane Consumption ◽  
Sessile Oak

<p>Soils play an important role of atmospheric methane sink, consuming about 30 Tg year<sup>-1</sup>. Methane consumption is carried out by methanotrophic bacteria whose activity can be affected by different environmental factors. One of the most important factors that impact on methane consumption is the air-filled porosity of soil (AFP), which depends on its total porosity (P) and its water content (SWC). A high AFP enhances gas diffusion in soil, and therefore methane consumption. In forests, P is thought to increase with stand age because of soil decompaction by tree roots and SWC is thought to decrease because of a high evapotranspiration. Another factor that can affect methane consumption and thought to decrease with the aging of forest stands is mineral nitrogen (Nmin) and particularly ammonium that competes with methane for the active site of methane monooxygenase, thus reducing methane oxidation. However only few studies have addressed the effects of stand aging on soil methane consumption.</p><p>Our objective was to confirm the hypothesis that methane consumption by forest soil increases with stand age, in relation with an increase AFP and a decrease Nmin. We carried out this study in a chronosequence of 16 stands of sessile oak divided into six age classes (20-30, 40-60, 60-70, 85-90, 125-130 and 140-145). Three sampling campaigns were conducted in late summer 2018 and 2019 (periods of maximum AFP) and in early spring 2018 (period of minimum AFP). Soil methane consumption was measured by incubating the five first centimetres of soil cores at 20°C and by measuring the decrease of CH<sub>4</sub> concentration in the incubation chamber with a laser-based CH<sub>4</sub> analyser.</p><p>In contrast to our hypothesis, we did not find any significant effect of stand age on Nmin, P, SWC and AFP, nor on methane consumption. However, methane consumption was higher in stands with high values of AFP and low value of SWC, whatever their age. AFP, through differences in SWC, appeared to be the main driver of soil methane consumption in our study site, explaining both seasonal variations and variations among stands, that could not however be related to their age.</p>

Isolation of Stenotrophomonas maltophilia from Clinical Samples in Some Hospitals in Shiraz, Iran

2020 ◽  
pp. 1-3
Author(s):  
Majid Baserisalehi ◽  
Samira Zarezadeh ◽  
Majid Baserisalehi ◽  
Saeed Shoa
Keyword(s):  
Stenotrophomonas Maltophilia ◽  
Enterobacter Aerogenes ◽  
Late Summer ◽  
Early Spring ◽  
Clinical Samples ◽  
Bacillus Species ◽  
Microbiological Analysis ◽  
Blood Samples ◽  
Healthcare Facilities ◽  
Phenotypic Methods

Stenotrophomonas maltophilia is an emerging pathogenic non-fermentative Gram-negative Bacillus species. It has caused many nosocomial infections and can be isolated from various hospital wards and healthcare facilities. Research has shown that most of its strains are inherently resistant to many antibiotics and have multidrug resistance. This research intended to determine its occurrence frequency at some Hospitals in shiraz, Iran. The present study was conducted in six months (from early spring to late summer 2019). Clinical samples (Blood, Urine and cerebrospinal fluid (CSF)) collected from 120 patients afflicted with various infections. The samples were transferred to the Laboratory and subjected to microbiological analysis. Identification of the isolates was carried out by phenotypic methods and Stenotrophomonas maltophilia isolates verified using molecular methods. In total, various bacteria were isolated from 84 clinical samples. The isolates were Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, Stenotrophomonas maltophilia, Staphylococcus aureus and Pseudomonas aeruginosa. Stenotrophomonas maltophilia was isolated from 17 (20.2%) positive samples and most of them were isolated from blood samples. Our finding indicated that Stenotrophomonas maltophilia isolated more from blood samples follow by CSF sample. In addition, our finding illustrated that Stenotrophomonas maltophilia can be considered as the common nosocomial agent at hospitals in Shiraz, Iran.

scholarly journals Effect of Herbicides on the Management of the Invasive Weed Solanum rostratum Dunal (Solanaceae)

Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 284
Author(s):  
Jackline Abu-Nassar ◽  
Maor Matzrafi
Keyword(s):  
Growth Stage ◽  
Late Summer ◽  
Early Spring ◽  
Growth Stages ◽  
Weed Species ◽  
Invasive Weed ◽  
Solanum Rostratum ◽  
Stage 4 ◽  
Chemical Solutions ◽  
Late Growth

Solanum rostratum Dunal is an invasive weed species that invaded Israel in the 1950s. The weed appears in several germination flashes, from early spring until late summer. Recently, an increase in its distribution range was observed, alongside the identification of new populations in the northern part of Israel. This study aimed to investigate the efficacy of herbicide application for the control of S. rostratum using two field populations originated from the Golan Heights and the Jezreel Valley. While minor differences in herbicide efficacy were recorded between populations, plant growth stage had a significant effect on herbicide response. Carfentrazone-ethyl was found to be highly effective in controlling plants at both early and late growth stages. Metribuzin, oxadiazon, oxyfluorfen and tembutrione showed reduced efficacy when applied at later growth stage (8–9 cm height), as compared to the application at an early growth stage (4–5 cm height). Tank mixes of oxadiazon and oxyfluorfen with different concentrations of surfactant improved later growth stage plant control. Taken together, our study highlights several herbicides that can improve weed control and may be used as chemical solutions alongside diversified crop rotation options. Thus, they may aid in preventing the spread and further buildup of S. rostratum field populations.

DNA Isolation from Recalcitrant Materials Such as Tree Roots, Bark, and Forest Soil for the Detection of Fungal Pathogens by Polymerase Chain Reaction

1998 ◽  
Vol 262 (1) ◽  
pp. 79-82 ◽  
Author(s):  
Günther Bahnweg ◽  
Steffen Schulze ◽  
Evelyn M. Möller ◽  
Hilkea Rosenbrock ◽  
Christian Langebartels ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Forest Soil ◽  
Fungal Pathogens ◽  
Dna Isolation ◽  
Chain Reaction ◽  
Tree Roots ◽  
Polymerase Chain

scholarly journals Meteorological factors affect the hand, foot, and mouth disease epidemic in Qingdao, China, 2007–2014

2016 ◽  
Vol 144 (11) ◽  
pp. 2354-2362 ◽  
Author(s):  
F. C. JIANG ◽  
F. YANG ◽  
L. CHEN ◽  
J. JIA ◽  
Y. L. HAN ◽  
...  
Keyword(s):  
Meteorological Factors ◽  
Enterovirus 71 ◽  
Rank Correlation ◽  
Foot And Mouth Disease ◽  
Late Summer ◽  
Atmospheric Temperature ◽  
Early Spring ◽  
Mouth Disease ◽  
Foot And Mouth ◽  
Spearman Rank Correlation Analysis

SUMMARYHand, foot, and mouth disease (HFMD) has caused public health concerns worldwide. We aimed to investigate the effect of meteorological factors on the HFMD epidemic in Qingdao, a port city in China. A total of 78641 cases were reported in Qingdao between January 2007 and December 2014. Of those, 71084 (90·39%) occurred in children aged 0–5 years, with an incidence of 1691·2/100000. The incidence increased from early spring, peaked between spring and summer, and decreased in late summer. Aetiological agents in all severe cases and selected mild cases were characterized by examining throat swabs. Except for enterovirus 71 (EV71) and coxsackievirus A16 (CA16), other EVs caused >50% of the HFMD cases between 2011 and 2014. EV71 was more frequent in the off-peak months than in the peak months and prone to causing more severe cases compared to CA16 (χ2 = 46·3, P < 0·001). CA10 caused more severe HFMD than did CA6 (χ2 = 20·49, P < 0·001) and all non-CA10 EVs (χ2 = 41·01, P < 0·001). Community-derived HFMD cases accounted for 65·11%. Spearman rank correlation analysis showed that HFMD incidence in children aged 0–5 years was positively correlated with atmospheric temperature (rs = 0·77, P < 0·001), relative humidity (rs = 0·507, P < 0·001), and precipitation (rs = 0·328, P < 0·001). Climate changes and CA10 surveillance in communities should be integrated into the current prophylactic programme.

scholarly journals Fish nursery value of algae habitats in temperate coastal reefs

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6797 ◽  
Author(s):  
Hilmar Hinz ◽  
Olga Reñones ◽  
Adam Gouraguine ◽  
Andrew F. Johnson ◽  
Joan Moranta
Keyword(s):  
Juvenile Fish ◽  
Strong Association ◽  
Late Summer ◽  
Early Spring ◽  
Rocky Reef ◽  
Term Survival ◽  
Fish Nursery ◽  
Prey Biomass ◽  
Reduced Height ◽  
Time Of Year

The nursery function of coastal habitats is one of the most frequently mentioned and recognized ecosystem services in the valuation of coastal ecosystems. Despite its importance our understanding of the precise habitat parameters and mechanisms that make a habitat important as a nursery area is still limited for many species. The study aimed to establish the importance of different algae morphotypes in providing shelter and food for juvenile coastal fish during the main settlement peaks, in early spring and late summer, in littoral rocky reef systems in the Northwestern Mediterranean. The results of our study showed strong seasonal differences in algae cover, composition and height between the two sampling periods. Overall, during spring the algae were well developed, while in late summer, both density and height, of most algae decreased considerably. Equally, prey biomass, in form of suitable sized invertebrate fauna associated to the algae, decreased. Accordingly, the shelter and food for the fish settling in this habitat during late summer were less abundant, indicating a mismatch between the observed presence of juvenile fish and optimal habitat conditions. Differences in prey densities were detected between algae morphotypes, with structurally more complex algae, such as Cystoseira spp. and Halopteris spp. consistently containing more prey, independent of season, compared to simpler structured morphotypes such as Dictoytales. The study furthermore related juvenile fish density to habitats dominated by different algae morphotypes. Out of the three-study species (Diplodus vulgaris, Symphodus ocellatus, Coris julis) only S. ocellatus showed a significant association with an algae habitat. S. ocellatus related positively to habitats dominated by Dictoytales which provided the highest cover during late summer but had the lowest prey densities. A strong association of this species with Cystoseira, as reported by other studies, could not be confirmed. Cystoseira was abundant within the study area but in a state of dieback, showing loss and reduced height of foliage, typical for the time of year within the study area. It is therefore likely that algae-fish associations are context-dependent and that several algae species may fulfil similar functions. We also discovered that prey biomass did not appear to have an important effect on juvenile abundances. Nevertheless, the availability of prey may influence juvenile fish condition, growth performance and ultimately long-term survival. We therefore suggest that future studies on habitat quality should also include, besides abundance, indicators related to the condition and growth of juveniles.

scholarly journals Sexual maturation in Atlantic salmon male parr may be triggered both in early spring and late summer under standard farming conditions

2021 ◽  
Author(s):  
Elia Ciani ◽  
Kristine von Krogh ◽  
Rasoul Nourizadeh-Lillabadi ◽  
Ian Mayer ◽  
Romain Fontaine ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Sexual Maturation ◽  
Late Summer ◽  
Early Spring ◽  
Plasma Testosterone ◽  
Farmed Salmon ◽  
Early Maturing ◽  
Advanced Stages ◽  
One Year ◽  
Immature Fish

AbstractMale Atlantic salmon (Salmo salar) display different sexual strategies, maturing either as parr during the freshwater phase (as sneaky spawners), or as post smolts following one or several years at sea. First sexual maturation (puberty) occurs at different times depending on environmental and genetic factors. To improve our knowledge on the timing (age and season) of first sexual maturation in Atlantic salmon male parr, we investigated pubertal activation in second generation farmed salmon from the Norwegian river Figgjo, reared under natural conditions of photoperiod and water temperature. Histological analysis, in combination with morphometric measurements, plasma androgen levels and pituitary gonadotropin gene expression analysis revealed that, as previously reported, some male parr initiated early sexual maturation in spring at one year of age. Interestingly, some male parr were observed to initiate sexual maturation already in autumn, six months after hatching (under-yearlings), much earlier than reported in previous studies. One-year old maturing males showed a low induction in gonadotropin levels, while under-yearling maturing males displayed a significant increase in fshb transcripts as compared to immature fish. Plasma testosterone, detectable also in immature males, increased constantly during testes development, while 11-ketotestosterone, undetectable in immature and early maturing males, increased during more advanced stages of maturation. A mild feminization of the testes (ovotestes) was detected in a subset of samples. This study brings new knowledge on the little investigated field of sexually maturing under-yearlings in Atlantic salmon. This is also the first study comparing the physiology of under-yearling vs one-year old maturing male parr, thus bringing new insights to the remarkable plasticity of Atlantic salmon puberty.

scholarly journals Araneus bonali sp. n., a novel lichen-patterned species found on oak trunks (Araneae, Araneidae)

ZooKeys ◽  
2018 ◽  
Vol 779 ◽  
pp. 119-145
Author(s):  
Eduardo Morano ◽  
Raul Bonal
Keyword(s):  
New Species ◽  
Late Summer ◽  
Molecular Data ◽  
Early Spring ◽  
Agricultural Landscapes ◽  
Nature Management ◽  
Forest Patches ◽  
Western Spain ◽  
Morphological And Molecular Data ◽  
Forest Arthropods

The new species Araneusbonali Morano, sp. n. (Araneae, Araneidae) collected in central and western Spain is described and illustrated. Its novel status is confirmed after a thorough revision of the literature and museum material from the Mediterranean Basin. The taxonomy of Araneus is complicated, but both morphological and molecular data supported the genus membership of Araneusbonali Morano, sp. n. Additionally, the species uniqueness was confirmed by sequencing the barcode gene cytochrome oxidase I from the new species and comparing it with the barcodes available for species of Araneus. A molecular phylogeny, based on nuclear and mitochondrial genes, retrieved a clade with a moderate support that grouped Araneusdiadematus Clerck, 1757 with another eleven species, but neither included Araneusbonali sp. n. nor Araneusangulatus Clerck, 1757, although definitive conclusions about the relationships among Araneus species need more markers examined and a broader taxonomic coverage. The new species was collected on isolated holm oaks and forest patches within agricultural landscapes. Adults were mostly trapped on tree trunks, where their lichen-like colours favour mimicry, while juveniles were collected on tree branches. Specimens were never found either in ground traps or grass samples. This species overwinters as egg, juveniles appear in early spring, but reproduction does not take place until late summer-early autumn. Araneusbonali Morano, sp. n. was found in the same locality from where another new spider species was described. Nature management policies should thus preserve isolated trees as key refuges for forest arthropods in agricultural landscapes, as they may be hosting more unnoticed new species. After including Araneusbonali Morano, sp. n. and removing doubtful records and synonymies, the list of Araneus species in the Iberian Peninsula numbers eight.

scholarly journals MANAWATU DAIRY FARMERS EXPERIENCES WITH MATUA PRAIRIE GRASS

1988 ◽  
pp. 185-186 ◽  
Author(s):  
M.D. Sellars
Keyword(s):  
White Clover ◽  
Late Summer ◽  
Early Spring ◽  
Trial And Error ◽  
Dairy Farmers ◽  
Prairie Grass

Manawatu dairy farmers have been quick to appreciate the possible benefits of a pasture species that can out-perform conventional ryegrass white clover based pastures. A survey conducted by Grasslands Division, DSIR in 1985 showed knowledge and use of Matua praire grass by dairy farmers in the Wellington province were 70% and 42% respectively, compared with the national figures of 55% and 29% for dairy farmers, and 32% and 9% for non-dairy farmers. When Matua was first released little data was available as to how best to sow the seed, what seed mixes are the most appropriate, how to manage the establishing pasture, and how to get the best from an established pasture. Researchers and pioneering farmers right around the country have by trial and error found the answers to most of these questions. The stimulus to find the answers was always the promise that Matua offered, that of 15 to 30% extra drymatter production compared to standard ryegrass pastures. Not only is there more annual drymatter, but the extra comes at very useful times for the dairyfarmer: winter, early spring and late summer.

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