scholarly journals Influence of Temperature and Relative Humidity on Air Pollution in Addis Ababa, Ethiopia

2020 ◽  
Vol 2 (2) ◽  
Author(s):  
Endeshaw Lake
Keyword(s):  
Relative Humidity ◽  
Negative Correlation ◽  
Addis Ababa ◽  
Dry Season ◽  
Clear Correlation ◽  
Wet Season ◽  
Co Concentration ◽  
Reduction Of Nox ◽  
One Year ◽  
Atmospheric Variables

In this paper we access the effects of two atmospheric variables (temperature and relative humidity) on two important pollutants in the atmosphere (Nitrogen oxides (NOx) and carbon monoxide (CO)) by using one year (2016) data of Addis Ababa. Temperature has impact on atmospheric mixing and cause for the reduction of NOx as temperature increases. There are positive correlation between temperature and CO concentration from January to April with (R2 = 0.69), negative correlation from May to August with (R2 = 0.92) and no correlation for the remaining months. NOx and CO have moderate positive and negative correlation with relative humidity during the months January-April (R2 = 0.294 for NOx and R2 = 0291 for CO) and in the months May-August are R2 = 0.97 and R2 = 0.15 for NOx and CO respectively. But there are no clear correlation between the NOx and CO with relative humidity from September-December. NOx concentrations during wet season was almost about twice that of the dry season, but no such difference was observed in the case of CO. The seasonal average air temperature in wet season is relatively lower than dry season. NOx exhibited positive and CO negative seasonal correlations with relative humidity.

scholarly journals Branch elongation and diameter growth were temporally dissociatedin "cerrado" tree species

Hoehnea ◽  
2009 ◽  
Vol 36 (3) ◽  
pp. 437-444 ◽  
Author(s):  
Davi Rodrigo Rossatto
Keyword(s):  
Water Status ◽  
Carbon Assimilation ◽  
Dry Season ◽  
Diameter Growth ◽  
Wet Season ◽  
Dry Period ◽  
Central Brazil ◽  
Branch Growth ◽  
Tree Community ◽  
One Year

Here is a communicating about time differences between branch and diameter growth in a tree community of ten species in Neotropical savanna ("cerrado") of Central Brazil. This work was conducted to study branch expansion and diameter growth in a period of one year between 2006 and 2007. Branch growth had begin in middle dry season and had the peak occurrence during the dry period in September, while diameter growth had begin in late dry season and peaked in the middle of wet season in December. The majority of species followed the same pattern. Branch growth did not have relation with rainfall, while diameter growth had a clear and positive relation with rainfall records. These results suggested that branch growth was not depend on rainfall but only on water status recover, while diameter growth probably depends strongly on water and to carbon assimilation that occurs after branch and leaf expansion.

scholarly journals On the epidemiology of helminth parasites in Hangul Deer Cervus hanglu hanglu (Mammalia: Artiodactyla: Cervidae) of Dachigam National Park, India

2021 ◽  
Vol 13 (1) ◽  
pp. 17517-17520
Author(s):  
Naziya Khurshid ◽  
Hidayatullah Tak ◽  
Ruqeya Nazir ◽  
Kulsum Ahmad Bhat ◽  
Muniza Manzoor
Keyword(s):  
Risk Factors ◽  
National Park ◽  
Helminth Infection ◽  
Dry Season ◽  
Helminth Parasites ◽  
Wet Season ◽  
Factors Associated ◽  
Dictyocaulus Viviparus ◽  
Dachigam National Park ◽  
One Year

A one-year study conducted to ascertain the prevalence and risk factors associated with helminth infection in Hangul Deer Cervus hanglu hanglu at Dachigam National Park revealed that 40.45% (89 of 220 samples) were infected with four helminth species including Heamonchus contortus, Trichuris ovis, Dictyocaulus viviparus, and Moneizia expansa.  The study signified that the infection was more prevalent during the dry season (summer and autumn) as compared to the wet season (winter and spring).  The overall prevalence of Heamonchus contortus was the highest (23.18%) followed by Trichuris ovis (8.18%), followed by Dictyocaulus viviparus (5.45%), and Moneizia expansa (3.63%).  The present study should be of importance in conserving the erstwhile state animal, listed as Critically Engendered in 2017 by IUCN.

Phenological changes in a Sumatran rain forest

1986 ◽  
Vol 2 (4) ◽  
pp. 327-347 ◽  
Author(s):  
C. P. Van Schaik
Keyword(s):  
Leaf Litter ◽  
Rain Forest ◽  
Seasonal Pattern ◽  
Dry Season ◽  
Wet Season ◽  
Phenological Changes ◽  
Young Leaves ◽  
Fig Trees ◽  
One Year ◽  
Made In

ABSTRACTPhenological observations were made in a Sumatran rain forest during three years (1980–1982). Phenological changes followed a consistent seasonal pattern. The abundance of young leaves and the fall of leaf litter peaked between December and February (first dry season); flowers were most abundant between January and April (first dry and first wet sea son), and ripe fruits in July-August (the second dry season). The fruit of strangling fig trees showed peaks in April and October, both wet season months. Within the study area there was variation in both the phase and the amplitude of the phenological cycles. One year, 1981, displayed mast flowering and fruiting. The observations indicate that the conditions for production were better during the mast year, a finding that facilitates our understanding of the evolution of mast fruiting.

scholarly journals Meteorological parameter anomalies and anomalous radio propagation over Nigeria

2020 ◽  
Vol 9 (1) ◽  
pp. 34-50
Author(s):  
I. Emmanuel ◽  
K.D. Adedayo ◽  
B. Adeyemi ◽  
O.S. Ojo
Keyword(s):  
Spatial Distribution ◽  
Relative Humidity ◽  
Negative Correlation ◽  
Meteorological Parameter ◽  
Radio Propagation ◽  
Monthly Variation ◽  
Wet Season ◽  
Strong Negative Correlation ◽  
Positive Correlation ◽  
Seasonal Movement

Distribution and variation of anomalous radio propagation, temperature and relative humidity anomalies were obtained and analyzed using six years (2010-2015) Era interim data. Seasonal spatial distribution of refractivity gradient and its components were analyzed. The result showed that about 90% of wet component contributed to the variation of refractivity gradient. Highest range of refractivity gradients and its wet components were obtained during the wet season. The result of correlation between ducting occurrence and temperature showed strong negative correlation except in Lagos where positive correlation of 3% was observed. However, positive correlation which ranges between 39% and 70% exist between duct occurrence and relative humidity except in Lagos in Nigeria. Refractivity gradients, relative humidity anomaly and temperature experience a monthly variation. These variations can be attributed to the seasonal movement of inter-tropical discontinuity (ITD) across Nigeria. Keywords: anomalous, anomaly, correlation, ITD

scholarly journals Vertical Arthropod Dynamics across Organic Matter Fractions in Relation to Microclimate and Plant Phenology

2020 ◽  
Author(s):  
María F. Barberena-Arias ◽  
Elvira Cuevas
Keyword(s):  
Organic Matter ◽  
Species Composition ◽  
Plant Species ◽  
Dry Season ◽  
Temperature Pattern ◽  
Wet Season ◽  
Key Factor ◽  
Organic Matter Fractions ◽  
One Year ◽  
Arthropod Abundance

Plant diversity is a key factor influencing belowground dynamics including microclimate and decomposer arthropod communities. This study addresses the effect of individual plant species on belowground arthropods by focusing on seasonal variations in precipitation, temperature and arthropods along the vertical organic matter profile. In the Guanica Dry Forest, Puerto Rico, microclimate was described and 5 plant species and 10 trees/species were selected. Under each tree, for one year, temperature was measured and samples collected along the organic matter fractions. Collected arthropods were standardized to ind/m2, identified to Order/Family and assigned to morphotypes. The annual temperature pattern was similar for all species and OM fractions. Arthropod abundance was similar among plant species and higher in humus than in litter fractions. Richness and species composition were different among plant species and OM fractions. All plant species and OM fractions showed low arthropod abundance and richness, and similar arthropod species composition in the dry season, while in the wet season abundance and richness were higher and species composition varied across plant species and OM fractions. These data suggest that arthropods form specific assemblages under plant species and stages of decomposition that, during the dry season, represent a subgroup adapted to extreme environmental conditions.

scholarly journals Egg fertility and hatchability in Avians broiler-breeder hens under humid tropical conditions

2021 ◽  
Vol 42 (2) ◽  
pp. 21-27
Author(s):  
M. O. Abioja ◽  
J. A. Abiona ◽  
T. J. Williams ◽  
O. F. Smith ◽  
I. J. Abioja ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Negative Correlation ◽  
Rainy Season ◽  
Dry Season ◽  
Broiler Breeder ◽  
Breeder Hens ◽  
Dry Spell ◽  
Tropical Conditions ◽  
Broiler Breeder Hens ◽  
Egg Fertility

Abstract Impact of temperature and humidity in different month of lay was evaluated on fertility and hatchability in broiler breeder hens reared in Sapele, Nigeria. Six million, six hundred and nineteen thousand, seven hundred and forty six eggs from flocks of Avians broiler-breeder hens reared between 2005 and 2006 in a farm located in Sapele were used. Egg fertility and hatchability (P<0.001) were significantly affected by month of lay. The month of June recorded the highest egg fertility were the highest in hatchability of set eggs and fertile eggs was in May. However, fertility and hatchability for all months between May and October were not different from each other but significantly higher than the values obtained in January - April and November-December. Months of May-October were the rainy season in Sapele while dry spell covers November to April. Temperature had significant (P<0.05) but negative correlation with egg fertility (r= -0.31), hatchability of set eggs (r= -0.26) and fertile eggs (r = -0.12) respectively. Correlation of amount of rainfall with egg fertility (r = 0.29), ability of set eggs (r = 0.22) and of fertile eggs (r = 0.06) was positive (P<0.05). Relative humidity had positive (P<0.05) correlation with egg fertility (r = 0.25), hatchability of set eggs (r= 0.17) and fertile eggs (r= 0.48). Correlation of number of rainy day with egg fertility (r = 0.40), hatchability of set eggs (r = 0.34) and fertile eggs (r = 0.71) was positive and strong (P<0.05). It can be concluded that high pen temperature especially during dry season does adversely affect egg fertility and hatchability in Avians broiler-breeder hens under humid tropical conditions.

Influence of pasture type and supplement on fertility and liveweight of cows, and progeny growth rate in the dry tropics of northern Queensland

1983 ◽  
Vol 23 (120) ◽  
pp. 4 ◽  
Author(s):  
RG Holroyd ◽  
PK O'Rourke ◽  
MR Clarke ◽  
ID Loxton
Keyword(s):  
Growth Rate ◽  
Reproductive Performance ◽  
Fold Increase ◽  
Dry Season ◽  
Wet Season ◽  
Calf Growth ◽  
Dry Tropics ◽  
Stylosanthes Humilis ◽  
Native Pasture ◽  
One Year

The reproductive performance of cows and growth rate of their calves to weaning was examined over a four-year period (1973-1977). Cows grazed either native pasture stocked at 1cowl4 ha, or native pasture oversown with Townsville stylo (Stylosanthes humilis) and fertilized with superphosphate stocked at 1 cow/2 ha. Animals were supplemented on each pasture type with urea-molasses in the dry season, phosphorus all year round plus urea-molasses in the dry season, or were unsupplemented. Mating was for three months from mid-January. Calving began towards the end of the dry season and cows lactated through the following wet season. Cows grazing fertilized legume pasture had significantly higher conception rates and earlier calving dates in one year only. In all years, foetal and calf losses between pregnancy diagnosis and weaning were lower on native pasture than on fertilized legume pasture. Cows grazing fertilized legume pasture were generally in better body condition and heavier throughout and their calves grew faster to weaning than on native pasture. Fertilized legume pasture produced a 2.4 fold increase over that of native pasture in cow and calf liveweight per unit area (382.7 kg/ha vs 159.8 kg/ha) over the four years. Supplementation did not influence liveweight or reproductive performance of cows or calf growth rate except during the final dry season when non-supplemented cows lost significantly more weight than those supplemented with phosphorus and urea.

An evaluation by bioassay of the persistence of DDT deposits on riverine vegetation in the Northern Guinea Savannah vegetation Zone of Nigeria and observations on the factors influencing the availability of deposits to Glossina palpalis (R.-D.)

1963 ◽  
Vol 54 (3) ◽  
pp. 497-508 ◽  
Author(s):  
D. A. T. Baldry
Keyword(s):  
Climatic Factors ◽  
Dry Season ◽  
Tsetse Flies ◽  
Wet Season ◽  
Vegetation Zone ◽  
Resting Sites ◽  
Riverine Vegetation ◽  
One Year ◽  
Reduced Toxicity ◽  
Glossina Palpalis

The persistence of DDT deposits, derived from dilutions of an emulsion concentrate, Arkotine D.25, on the leaves of riverine vegetation in the Northern Guinea Savannah vegetation zone of Nigeria was studied in the laboratory by a bioassay method using teneral females of Glossina palpalis (R.-D.) as test insects. Irrespective of whether sprayed in the dry or wet season, deposits derived from sprays containing 5.0 per cent. DDT produced by the Warley knapsack sprayer were still reasonably toxic one year after spraying. Deposits derived from sprays having a concentration of DDT varying from 1·25 to 5·0 per cent. DDT were equally toxic when young, but those from the lower concentrations were weathered much more rapidly than those from the 5·0 per cent, sprays. Young deposits produced by Warley and Motoblo sprayers were equally toxic, but deposits from the Motoblo deteriorated more rapidly than those of the Warley.The toxicity of the DDT deposits on leaves varied regularly with the seasons. The various climatic factors that it is thought influenced the variations in toxicity are discussed. Accumulations of wind-blown dust on the leaves during the late dry season and low evaporation rates at the height of the rains appear to be responsible for reduced toxicity at those times; in the early wet season, the occasional violent storm probably washes off the leaves the dust accumulated during the dry season and makes the insecticidal deposits once more available. Heavy rainfall is important in removing the insecticidal deposits from the vegetation, and leaf decay and refoliation are important in reducing the availability of the deposits. The implications of these variations in toxicity and factors that reduce the availability of the deposits are discussed in relation to the eradication of riverine tsetse.Great differences in the rates of foliage decay and refoliation occur between different riverine plants, and it is suggested that a thorough study of this feature in riverine plants and of resting sites favoured by tsetse flies might reveal information that would enable tsetse to be eradicated by selective spraying of certain plant species only.

Effects of light availability and rainfall on leaf production in a moist tropical forest in central Panama

1998 ◽  
Vol 14 (3) ◽  
pp. 309-321 ◽  
Author(s):  
JOHN A. BARONE
Keyword(s):  
Tropical Forest ◽  
Tropical Forests ◽  
Light Availability ◽  
Dry Season ◽  
Wet Season ◽  
Leaf Production ◽  
Active Radiation ◽  
One Year ◽  
The Relationship ◽  
Central Panama

New leaf production in seasonal tropical forests may result from changes in water or light availability. In this study, the relationship between leaf flushing, photosynthetically active radiation (PAR) and rainfall was examined for understorey saplings in a moist tropical forest over one year. During the wet season, weeks with greater PAR were correlated with a greater proportion of saplings flushing new leaves during subsequent weeks in nine out of ten species. Rainfall was negatively correlated with subsequent leafing during the wet season for six of ten species. However, during the dry season, rainfall was positively correlated with leafing during the following weeks for six species, but the relationship was much weaker. PAR in the dry season was negatively correlated with flushing in eight species. These results support the hypothesis that under well-watered conditions, light limits leaf production, and peaks in insolation result in greater leaf production.

Seasonal patterns and influence of temperature on the daily activity of the diurnal neotropical rodent Necromys lasiurus

2010 ◽  
Vol 88 (3) ◽  
pp. 259-265 ◽  
Author(s):  
E. M. Vieira ◽  
L. C. Baumgarten ◽  
G. Paise ◽  
R. G. Becker
Keyword(s):  
Relative Humidity ◽  
Ambient Temperature ◽  
Activity Patterns ◽  
Dry Season ◽  
Diel Activity ◽  
Significant Activity ◽  
Positive Relation ◽  
Wet Season ◽  
Temperature Relation ◽  
Central Brazil

We investigated the relation between temperature and diel activity patterns of Necromys lasiurus (Lund, 1841) in 10 sites of open vegetation (grassland fields) in the Cerrado (savanna-like vegetation) of central Brazil. We used live traps equipped with timing devices during two trapping sessions: in the end of the dry season (session 1, October 2001) and in the wet season (session 2, January–February 2002). Necromys lasiurus is basically a diurnal rodent with more pronounced crepuscular and nocturnal activity in the dry season than in the wet season. Only in the wet season did we detect significant between-gender differences, with males being less active than females in the first hours after sunrise but more active between 0900 and 1200. There was no significant activity–temperature relation in the dry season, but in the wet season, both genders showed a positive relation between ambient temperature and activity. Individuals might be avoiding hot midday hours in the end of the dry season to minimize time exposure to a physiologically stressful condition caused by the joint action of high temperatures and extremely low relative humidity (<15%). In the rainy season, the high relative humidity (80%–90%) might allow the animals to show a positive relation between activity and ambient temperature.

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