The early effects of fire and grazing on bryophytes and lichens in tussock grassland and hummock sedgeland in north-eastern Tasmania

2009 ◽  
Vol 57 (7) ◽  
pp. 556 ◽  
Author(s):  
Anneka V. Ferguson ◽  
Emma J. Pharo ◽  
Jamie B. Kirkpatrick ◽  
Jon B. Marsden-Smedley

Little is known of the interactive effects of fire and grazing on cryptogam species and assemblages. These effects were observed for bryophyte and lichen species in Tasmanian tussock grassland and hummock sedgeland several months after experimental burning and fencing. A factorial design was used on 40 randomly located and treated pairs of 1 m × 1 m quadrats in each of the vegetation types. In total, 24 cryptogam taxa were found, with grassland having a greater taxon richness, as well as higher total cryptogam cover and a different species composition, to the hummock sedgeland. There was greater cryptogam cover in the burned quadrats than the unburned quadrats in the grassland. However, only bryophytes had different species composition between burned and unburned quadrats. There was a small but significant difference in richness in hummock sedgeland, with burned being richer than unburned. Three species were more abundant in the burned than in the unburned treatments in the grassland, whereas no species responded to treatment in the sedgeland and no species responded to grazing. The fact that no species or assemblage of species was significantly reduced in cover by the burns testifies to a high degree of cryptogam resilience to this disturbance. The total lack of negative grazing effects suggests cryptogams are not a major source of sustenance for the local vertebrate herbivores. These conclusions differ from those made elsewhere in the world.

2018 ◽  
Vol 24 (2) ◽  
Author(s):  
VIMLESH KUMAR TIWARI

Performance of developed genotype RMT 08-2 was evaluated in central, eastern and north-eastern states of India under rain-fed condition for quantitative and qualitative traits. It gave highest seed yield over checks in zone III and V. Morphologically plants were erect, medium spreading in nature and primary branches with dichotomous habit. Plants height ranged from 107124 (cm) which matured in 82-112 days. Mature seeds were round in shape and blackish brown in colour. No significant difference between RVT-2 and checks were observed for test weight trait. An average oil yield 485 (kg/h) was recorded over 7 places which was 10% higher than both checks i.e. 14.12% and 11.24% under AICRP trials. Maximum seed yield was obtained on farmers field during 2013-14 and 2014-15 which was 1500 (kg/h) and 1215 (kg/h) that is 33.42% and 26.30% respectively over farmers own seeds. At Morena center, highest seed yield (1753 kg/h) over Bhawani (1512 kg/h) was 15.94% higher than check whereas RVT-2 gave 2245 (kg/h) against Bhawani (1975 kg/h) which was 13.67% higher. DNA finger printing indicated that primers PUT-19, PUT-96, PUT-149, PUT-169, PUT-181 and PUT-271 are useful in generating unique profile of RVT-2 containing 27 bands for its discrimination from other varieties.


2021 ◽  
Author(s):  
Arkadiusz Nowak ◽  
Sebastian Świerszcz ◽  
Sylwia Nowak ◽  
Marcin Nobis

AbstractThis paper presents the results of phytosociological research on scree vegetation of the Pamir and south-western Tian Shan. We collected 222 phytosociological relevés during field studies conducted in 2015–2019, applying the Braun-Blanquet approach. We identified 21 plant communities on mobile and stabilized screes of colluvial cones, aprons and fans, inhabiting mainly the montane and alpine belts in several ranges (e.g. Peter the First, Alichur, Shugnan, Shachdarian, Darvaz, Rushan, Vanch, Fergana, Kyrgyz and Terskey ranges). As a result we provide the first comprehensive hierarchical syntaxonomic synopsis of scree communities at montane and alpine elevations in the eastern Middle Asia. The collected vegetation relevés represent the majority of the variation among the phytocoenoses of gravel, pebble, cobble and rock block slides and screes in the montane and alpine belts. As a result of field studies and Twinspan analyses, nine associations were identified on screes of the Pamir and western Tian Shan. All these communities were assigned to the Sileno brahuicae-Lactucetalia orientalis Nowak et al. 2021. Additionally, within the nitrophilous compact gravel screes one subassociation of Corydalidetum kashgaricae trigonelletosum gontscharovii was distinguished. In the most arid zone two additional plant associations and one subassociation were identified in gravelly semi-deserts zone. The main factors determining the species composition of the studied associations are scree mobility, rock particle size, elevation above sea level and slope inclination. Our research revealed considerable diversity of scree habitats of montane and alpine belts what might be astonishing regarding harsh environment of this mountainous territory. However, a great number of lineages that evolved here and particularly rich species pool of this habitat in Middle Asia facilitate remarkable diversity among vegetation of taluses and screes. The distinctiveness of species composition is additionally enhanced by high degree of endemism of chasmophytic habitats in the eastern part of Middle Asia. Despite recent developments, the prominent chasmophytic vegetation of Middle Asia still needs thorough studies focused on its relationship to semi-desert, tall-forb and petrophytic communities of high mountains of the Pamir, Hindu-Kush, Kunlun and Central Tian Shan.


Author(s):  
Nisha Patidar ◽  
Nitya Vyas ◽  
Shanoo Sharma ◽  
Babita Sharma

Abstract Objective Carbapenems are last resort antibiotics for multidrug-resistant Enterobacteriaceae. However, resistance to carbapenem is increasing at an alarming rate worldwide leading to major therapeutic failures and increased mortality rate. Early and effective detection of carbapenemase producing carbapenem-resistant Enterobacteriaceae (CRE) is therefore key to control dissemination of carbapenem resistance in nosocomial as well as community-acquired infection. The aim of present study was to evaluate efficacy of Modified strip Carba NP (CNP) test against Modified Hodge test (MHT) for early detection of carbapenemase producing Enterobacteriaceae (CPE). Material and Methods Enterobacteriaceae isolated from various clinical samples were screened for carbapenem resistance. A total of 107 CRE were subjected to MHT and Modified strip CNP test for the detection of CPE. Statistical Analysis It was done on Statistical Package for the Social Sciences (SPSS) software, IBM India; version V26. Nonparametric test chi-square and Z-test were used to analyze the results within a 95% level of confidence. Results Out of 107 CRE, 94 (88%) were phenotypically confirmed as carbapenemase producer by Modified strip CNP test and 46 (43%) were confirmed by Modified Hodge Test (MHT). Thirty-eight (36%) isolates showed carbapenemase production by both MHT and CNP test, 56 isolates (52%) were CNP test positive but MHT negative, eight (7%) isolates were MHT positive but CNP test negative and five (5%) isolates were both MHT and CNP test negative. There is statistically significant difference in efficiency of Modified CNP test and MHT (p < 0.05). Conclusion Modified strip CNP test is simple and inexpensive test which is easy to perform and interpret and gives rapid results in less than 5 minutes. It has high degree of sensitivity and specificity. Modified strip CNP test shows significantly higher detection capacity for carbapenemase producers as compared with MHT.


Land ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 357
Author(s):  
Jong Kyu Lee ◽  
Myeong Ja Kwak ◽  
Sang Hee Park ◽  
Han Dong Kim ◽  
Yea Ji Lim ◽  
...  

Plants are affected by the features of their surrounding environment, such as climate change and air pollution caused by anthropogenic activities. In particular, agricultural production is highly sensitive to environmental characteristics. Since no environmental factor is independent, the interactive effects of these factors on plants are essential for agricultural production. In this context, the interactive effects of ozone (O3) and supraoptimal temperatures remain unclear. Here, we investigated the physiological and stomatal characteristics of leaf mustard (Brassica juncea L.) in the presence of charcoal-filtered (target concentration, 10 ppb) and elevated (target concentration, 120 ppb) O3 concentrations and/or optimal (22/20 °C day/night) and supraoptimal temperatures (27/25 °C). Regarding physiological characteristics, the maximum rate of electron transport and triose phosphate use significantly decreased in the presence of elevated O3 at a supraoptimal temperature (OT conditions) compared with those in the presence of elevated O3 at an optimal temperature (O conditions). Total chlorophyll content was also significantly affected by supraoptimal temperature and elevated O3. The chlorophyll a/b ratio significantly reduced under OT conditions compared to C condition at 7 days after the beginning of exposure (DAE). Regarding stomatal characteristics, there was no significant difference in stomatal pore area between O and OT conditions, but stomatal density under OT conditions was significantly increased compared with that under O conditions. At 14 DAE, the levels of superoxide (O2-), which is a reactive oxygen species, were significantly increased under OT conditions compared with those under O conditions. Furthermore, leaf weight was significantly reduced under OT conditions compared with that under O conditions. Collectively, these results indicate that temperature is a key driver of the O3 response of B. juncea via changes in leaf physiological and stomatal characteristics.


2011 ◽  
Vol 37 (3) ◽  
pp. 230-238 ◽  
Author(s):  
J.R. Arévalo ◽  
L. de Nascimento ◽  
S. Fernández-Lugo ◽  
J. Mata ◽  
L. Bermejo

1970 ◽  
Vol 17 (1) ◽  
pp. 25-31 ◽  
Author(s):  
Anita Pokharel ◽  
Madhu Chhetri ◽  
Chiranjibi P Upadhyaya

Limited information is available on the species composition, above ground biomass and its relations to grazing in a trans-Himalayan rangeland. Its assessment is essential for long term conservation and management. In the present study, we compared species composition, phenology, diversity index and biomass between controlled (without grazing) and open (free grazing) plots to assess the effects of grazing in the selected experimental sites of Upper Mustang during July and November 2005. Species encountered were classified as high, medium, low and non palatable and in three life form categories-grasses, shrubs and forbs. The experimental sites are dominated by forbs (80%) followed by grasses (15%) and shrubs (5%). Disturbance caused by grazing affects the phenological characteristics of the plant community. Result also reveals that species diversity, maximum possible diversity, evenness and species richness was higher in the grazed plots during July and November. A comparison of the aboveground biomass in July showed that mean percentage biomass of high, medium and low palatable species is higher in ungrazed plots. In November, the percentage biomass of only medium palatable species was higher in ungrazed plots and rest of the category is higher in grazed plots. Significant difference in July, a peak growing seasons for most of the plant species in the region reveals that the pasture has impact of livestock grazing. Keywords: Biomass, diversity, grazing effect, rangeland, species Banko Janakari: A journal of forestry information for Nepal Vol.17(1) 2007 pp.25-31


2021 ◽  
Vol 7 (2) ◽  
pp. 195-199
Author(s):  
Helen Rosita J ◽  
Gnanaselvan J ◽  
Amudhavadivu S ◽  
Anna Kurian Mullasseril

Glaucoma is the leading cause of irreversible blindness, one of the risk factor recognised being high myopia. Intra ocular pressure may be normal in myopic patients, with optic nerve head glaucoma characteristics. Eye ball elongation and optic nerve head tilting may be present in patients with high myopia that will represent field defects mimicking glaucoma. Treating patients with myopia having suspected aspects of glaucoma may be a challenge but even more challenging is the diagnosis of glaucoma in myopic patients.: To evaluate the association of glaucoma features with myopia. To create the awareness regarding the long term follow up.: Patients in the age group of 15 to 45 years who had attended our institution over a period of one year who fulfilled the inclusion and exclusion criteria were subjected for this study. Fifty four patients who were diagnosed to have moderate or high degree myopia were selected for this analytical study. They were subjected to vision, ocular examination, tonometry and results obtained were analysed.: In our study moderate myopes constituted 55.5% and high myopes were 44.5%. The mean Intra ocular pressure and the mean corrected Intra ocular pressure in high myopes were observed to be higher than in moderate myopia. It was observed that higher prevalence of glaucoma was observed in high myopes.: There is a clinically as well as statistically significant difference between mean Intra ocular pressure and mean corrected Intra ocular pressure. So mean corrected Intra ocular pressure should be measured .From our study, there is a clear indication that there is increased prevalence of glaucoma in high myopes.


2021 ◽  
Vol 8 ◽  
Author(s):  
Yuanyuan Feng ◽  
Fei Chai ◽  
Mark L. Wells ◽  
Yan Liao ◽  
Pengfei Li ◽  
...  

In addition to ocean acidification, a significant recent warming trend in Chinese coastal waters has received much attention. However, studies of the combined effects of warming and acidification on natural coastal phytoplankton assemblages here are scarce. We conducted a continuous incubation experiment with a natural spring phytoplankton assemblage collected from the Bohai Sea near Tianjin. Experimental treatments used a full factorial combination of temperature (7 and 11°C) and pCO2 (400 and 800 ppm) treatments. Results suggest that changes in pCO2 and temperature had both individual and interactive effects on phytoplankton species composition and elemental stoichiometry. Warming mainly favored the accumulation of picoplankton and dinoflagellate biomass. Increased pCO2 significantly increased particulate organic carbon to particulate organic phosphorus (C:P) and particulate organic carbon to biogenic silica (C:BSi) ratios, and decreased total diatom abundance; in the meanwhile, higher pCO2 significantly increased the ratio of centric to pennate diatom abundance. Warming and increased pCO2 both greatly decreased the proportion of diatoms to dinoflagellates. The highest chlorophyll a biomass was observed in the high pCO2, high temperature phytoplankton assemblage, which also had the slowest sinking rate of all treatments. Overall, there were significant interactive effects of increased pCO2 and warming on dinoflagellate abundance, pennate diatom abundance, diatom vs. dinoflagellates ratio and the centric vs. pennate ratio. These findings suggest that future ocean acidification and warming trends may individually and cumulatively affect coastal biogeochemistry and carbon fluxes through shifts in phytoplankton species composition and sinking rates.


Author(s):  
Dr. AHMAD ALI AL- JABALI

This study aims at identifying the evaluation of learning resources rooms in public schools in Ajloun governorate from the point of view of their teachers. The study was based on the descriptive analytical method. The study population consisted of (107) male and female teachers. random. The study reached a set of results, The most important: The arithmetic averages of the responses of the study sample to evaluate the room of learning resources as a whole came with a high degree, with an average of (3.63) and the field of parents with a high degree, and an arithmetic average (3.92), followed by the teacher field, with an average (3.66). ), Then the student field, with an average (3.64), while the resource room field, the lowest average score, with an average (3.40), The results also showed that there is no statistically significant difference according to sex and educational qualification, and that there are statistically significant difference for the job experience variable for (11 years and above). To disseminate the experience of forming a support committee to all departments, institutions and programs working with people with special needs in the local community.


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