Models for predicting fire ignition probability in graminoids from boreo–temperate moorland ecosystems

2016 ◽  
Vol 25 (6) ◽  
pp. 679 ◽  
Author(s):  
Victor M. Santana ◽  
Rob H. Marrs
Keyword(s):  
Late Summer ◽  
Early Spring ◽  
Fuel Load ◽  
Probability Models ◽  
Rating Systems ◽  
Seasonal Differences ◽  
Ignition Probability ◽  
Critical Moisture ◽  
Fuel Moisture Content ◽  
Fire Ignition

An increase in both the frequency and severity of wildfires in boreo–temperate ecosystems is predicted. Therefore, to develop efficient fire rating systems, the relationship between the fuel moisture content (FMC) of vegetation and ignition thresholds needs to be determined. We developed fire ignition probability models for three graminoid species collected in central England, but common in boreo–temperate ecosystems (Eriophorum angustifolium, E. vaginatum and Molinia caerulea). Specifically, we assessed through laboratory experiments (1) seasonal differences between early spring and late summer in fuel traits such as height, fuel load, fuel bulk density and dead fuel load proportion, and (2) the role of these fuel traits, environmental conditions and dead FMC in determining the probability of ignition. There were seasonal differences in fuel traits among species, with an increase in dead fuel load proportion after winter. The dead FMC was the only variable determining initial sustained ignitions. However, the seasonal differences in dead fuel were not sufficient to affect the FMC threshold at which graminoids start to ignite. Graminoids begin to ignite at high levels of dead FMC, and there are differences between species (from 36.1% to 48.1%). This work assists in improving fire ignition predictions in graminoid-dominated ecosystems by providing warnings based on critical moisture thresholds.

scholarly journals No evidence of increased fire risk due to agricultural land abandonment in Sardinia (Italy)

2012 ◽  
Vol 12 (5) ◽  
pp. 1333-1336 ◽  
Author(s):  
C. Ricotta ◽  
D. Guglietta ◽  
A. Migliozzi
Keyword(s):  
Rural Areas ◽  
Agricultural Land ◽  
Plant Biomass ◽  
Fire Hazard ◽  
Fire Behavior ◽  
Land Abandonment ◽  
Fuel Load ◽  
Short Paper ◽  
Ignition Probability ◽  
Fire Ignition

Abstract. Different land cover types are related to different levels of fire hazard through their vegetation structure and fuel load composition. Therefore, understanding the relationships between landscape changes and fire behavior is of crucial importance for developing adequate fire fighting and fire prevention strategies for a changing world. In the last decades the abandonment of agricultural lands and pastoral activities has been the major driver of landscape transformations in Mediterranean Europe. As agricultural land abandonment typically promotes an increase in plant biomass (fuel load), a number of authors argue that vegetation succession in abandoned fields and pastures is expected to increase fire hazard. In this short paper, based on 28 493 fires in Sardinia (Italy) in the period 2001–2010, we show that there is no evidence of increased probability of fire ignition in abandoned rural areas. To the contrary, in Sardinia the decreased human impact associated with agricultural land abandonment leads to a statistically significant decrease of fire ignition probability.

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.

scholarly journals Modeling fire ignition probability and frequency using Hurdle models: a cross-regional study in Southern Europe

2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Marina D’Este ◽  
Antonio Ganga ◽  
Mario Elia ◽  
Raffaella Lovreglio ◽  
Vincenzo Giannico ◽  
...  
Keyword(s):  
Mediterranean Basin ◽  
Negative Binomial ◽  
Pearson Correlation ◽  
Fire Occurrence ◽  
Ignition Probability ◽  
Hurdle Models ◽  
Mediterranean Landscapes ◽  
The Mediterranean ◽  
Fire Ignition ◽  
The Mediterranean Basin

Abstract Background Wildfires play a key role in shaping Mediterranean landscapes and ecosystems and in impacting species dynamics. Numerous studies have investigated the wildfire occurrences and the influence of their drivers in many countries of the Mediterranean Basin. However, in this regard, no studies have attempted to compare different Mediterranean regions, which may appear similar under many aspects. In response to this gap, climatic, topographic, anthropic, and landscape drivers were analyzed and compared to assess the patterns of fire ignition points in terms of fire occurrence and frequency in Catalonia (Spain), Sardinia, and Apulia (Italy). Therefore, the objectives of the study were to (1) assess fire ignition occurrence in terms of probability and frequency, (2) compare the main drivers affecting fire occurrence, and (3) produce fire probability and frequency maps for each region. Results In pursuit of the above, the probability of fire ignition occurrence and frequency was mapped using Negative Binomial Hurdle models, while the models’ performances were evaluated using several metrics (AUC, prediction accuracy, RMSE, and the Pearson correlation coefficient). The results showed an inverse correlation between distance from infrastructures (i.e., urban roads and areas) and the occurrence of fires in all three study regions. This relationship became more significant when the frequency of fire ignition points was assessed. Moreover, a positive correlation was found between fire occurrence and landscape drivers according to region. The land cover classes more significantly affected were forest, agriculture, and grassland for Catalonia, Sardinia, and Apulia, respectively. Conclusions Compared to the climatic, topographic, and landscape drivers, anthropic activity significantly influences fire ignition and frequency in all three regions. When the distance from urban roads and areas decreases, the probability of fire ignition occurrence and frequency increases. Consequently, it is essential to implement long- to medium-term intervention plans to reduce the proximity between potential ignition points and fuels. In this perspective, the present study provides an applicable decision-making tool to improve wildfire prevention strategies at the European level in an area like the Mediterranean Basin where a profuse number of wildfires take place.

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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