Pola Arus Permukaan dan Kondisi Fisika Perairan di Sekitar Pulau Selayar pada Musim Peralihan 1 dan Musim Timur

2017 ◽  
Vol 2 (1) ◽  
pp. 83 ◽  
Author(s):  
Ahmad Bayhaqi ◽  
Mochamad Riza Iskandar ◽  
Dewi Surinati
Keyword(s):  
Surface Water ◽  
Average Velocity ◽  
River Flow ◽  
Climatic Factors ◽  
Monsoon Season ◽  
Surface Current ◽  
Current Pattern ◽  
Flow Discharge ◽  
Oceanographic Data ◽  
Mean Current

<strong>Surface Current Pattern and Physics Condition of Waters Around Selayar Island in the First Transitional and Southeast Monsoons. </strong> Seasonal observations of the flow of surface water and physics conditions around Selayar Island adjacent to Arlindo throughflow pathways of Makassar Strait have been conducted with a focus on the first transitional season and the southeast monsoon season. The purpose of this research is to obtain the pattern of seasonal surface current and physics characteristics of water column, i.e. temperature and salinity in Selayar Island waters during those seasons. The observations conducted on 22–27 May 2015 and 7–10 August 2015 illustrated the successive periods of the first transitional season and the southeast monsoon season. The methods used for taking oceanographic data such as temperature, salinity, and current were the stationary oceanographic measurement using CTD and currentmeter at 29 stations located in surrounding waters of Selayar Island. The surface current pattern generated from the interpolation process of the overall observation stations indicated that during the first transitional season the current moved eastward with an average velocity of 0.25 m/s. During the southeast monsoon season, the same pattern was still observed with a slightly higher average velocity of 0.26 m/s. The temperatures and salinity of Selayar Island waters during the southeast monsoon season were 2°C lower and 0.5 psu higher than during the first transitional season. Differences in mean current velocity values tended to be more affected by local tidal conditions. Different salinity was thought to be influenced by upwelling phenomena and local climatic factors such as rainfall, wind, and river flow discharge.

scholarly journals Remote sensing of environmental risk factors for malaria in different geographic contexts

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Andrea McMahon ◽  
Abere Mihretie ◽  
Adem Agmas Ahmed ◽  
Mastewal Lake ◽  
Worku Awoke ◽  
...  
Keyword(s):  
Risk Factors ◽  
Surface Water ◽  
Environmental Risk ◽  
Land Surface ◽  
Climatic Factors ◽  
Environmental Risk Factors ◽  
Environmental Data ◽  
Health Concern ◽  
Irrigated Agriculture ◽  
Boosted Regression Tree

Abstract Background Despite global intervention efforts, malaria remains a major public health concern in many parts of the world. Understanding geographic variation in malaria patterns and their environmental determinants can support targeting of malaria control and development of elimination strategies. Methods We used remotely sensed environmental data to analyze the influences of environmental risk factors on malaria cases caused by Plasmodium falciparum and Plasmodium vivax from 2014 to 2017 in two geographic settings in Ethiopia. Geospatial datasets were derived from multiple sources and characterized climate, vegetation, land use, topography, and surface water. All data were summarized annually at the sub-district (kebele) level for each of the two study areas. We analyzed the associations between environmental data and malaria cases with Boosted Regression Tree (BRT) models. Results We found considerable spatial variation in malaria occurrence. Spectral indices related to land cover greenness (NDVI) and moisture (NDWI) showed negative associations with malaria, as the highest malaria rates were found in landscapes with low vegetation cover and moisture during the months that follow the rainy season. Climatic factors, including precipitation and land surface temperature, had positive associations with malaria. Settlement structure also played an important role, with different effects in the two study areas. Variables related to surface water, such as irrigated agriculture, wetlands, seasonally flooded waterbodies, and height above nearest drainage did not have strong influences on malaria. Conclusion We found different relationships between malaria and environmental conditions in two geographically distinctive areas. These results emphasize that studies of malaria-environmental relationships and predictive models of malaria occurrence should be context specific to account for such differences.

scholarly journals Impact of Climate Change on Water Availability and Food Security of Nepal

2012 ◽  
pp. 59-63
Author(s):  
Roshan Kumar Mehta ◽  
Shree Chandra Shah
Keyword(s):  
Climate Change ◽  
Crop Production ◽  
Climatic Factors ◽  
Monsoon Season ◽  
Groundwater Table ◽  
Maximum Temperature ◽  
Aquatic Life ◽  
Temperature And Precipitation ◽  
Average Maximum ◽  
Water Scarce

The increase in the concentration of greenhouse gases (GHGs) in the atmosphere is widely believed to be causing climate change. It affects agriculture, forestry, human health, biodiversity, and snow cover and aquatic life. Changes in climatic factors like temperature, solar radiation and precipitation have potential to influence agrobiodiversity and its production. An average of 0.04°C/ year and 0.82 mm/year rise in annual average maximum temperature and precipitation respectively from 1975 to 2006 has been recorded in Nepal. Frequent droughts, rise in temperature, shortening of the monsoon season with high intensity rainfall, severe floods, landslides and mixed effects on agricultural biodiversity have been experienced in Nepal due to climatic changes. A survey done in the Chitwan District reveals that lowering of the groundwater table decreases production and that farmers are attracted to grow less water consuming crops during water scarce season. The groundwater table in the study area has lowered nearly one meter from that of 15 years ago as experienced by the farmers. Traditional varieties of rice have been replaced in the last 10 years by modern varieties, and by agricultural crops which demand more water for cultivation. The application of groundwater for irrigation has increased the cost of production and caused severe negative impacts on marginal crop production and agro-biodiversity. It is timely that suitable adaptive measures are identified in order to make Nepalese agriculture more resistant to the adverse impacts of climate change, especially those caused by erratic weather patterns such as the ones experienced recently.DOI: http://dx.doi.org/10.3126/hn.v11i1.7206 Hydro Nepal Special Issue: Conference Proceedings 2012 pp.59-63

scholarly journals Reproductive biology of Ophiorrhiza caudata C.E.C.Fisch. (Rubiaceae), an endemic and endangered creeping perennial herb of the Western Ghats, India

2021 ◽  
Vol 13 (13) ◽  
pp. 20056-20065
Author(s):  
Maria Theresa ◽  
Appukuttan Kamalabai Sreekala ◽  
Jayalakshmi Mohanlal
Keyword(s):  
Seedling Establishment ◽  
Fruit Set ◽  
Floral Morphology ◽  
Climatic Factors ◽  
Monsoon Season ◽  
Natural Habitat ◽  
Flowering Phenology ◽  
Perennial Herb ◽  
In The Wild ◽  
The Western Ghats

Ophiorrhiza caudata is a creeping, perennial herb distributed along wet and shady areas. The species is distylous with two distinct floral morphs: pin and thrum. Flowering usually occurs during the monsoon season. No particular difference was noticed in the flowering phenology of the two morphs. Presently the species is self-incompatible, however, it shows a tendency towards intramorph compatibility. Fruit set is above 60% in open pollination and intermorph pollination. Bees and butterflies are the major pollinators. The pollen flow between the two floral morphs varies depending upon floral morphology and pollinators. Fruit is a bi-valved capsule which dehisces by a splashing drop mechanism. The seeds are very minute. The rate of seed germination and seedling establishment in the wild condition is very poor due to adverse climatic factors. Ophiorrhiza caudata is struggling for survival in its natural habitat, where habitat fragmentation, climatic factors and poor seedling establishment could account for its narrow distribution.

scholarly journals Formulated Mathematical Model for Delayed Particle Flow in Cascaded Sub-Surface Water Reservoirs with Validation on River Flow

2018 ◽  
Author(s):  
Ombaki Richard ◽  
Kerongo Joash ◽  
Okwoyo M. James
Keyword(s):  
Mathematical Model ◽  
Time Delay ◽  
Surface Water ◽  
Discrete Time ◽  
River Flow ◽  
Water Reservoir ◽  
Point Sources ◽  
Water Reservoirs ◽  
Discrete Time Delay ◽  
Mixing Problem

Pollution of sub-surface water reservoirs mainly rivers and streams through contaminated water point sources (CWPS) was studied. The objective was to formulate a discrete time delay mathematical model which describes the dynamics of reservoir pollution using mixing-problem processes that involve single species contaminants such as nitrates, phosphorous and detergents. The concentration &nbsp;of pollutants was expressed as a function of the inflow and outflow rates using the principle for the conservation of mass. Systems of ODEs generated from principles of mixing problems were refined into a system of DDEs so that the concentration of pollutant leaving the reservoir at time would be determined at some earlier instant, for the delay. The formulated model is a mathematical discrete time delay model which would be used to describe the dynamics of sub-surface water reservoir pollution. The results from the validation of the model were analyzed &nbsp;&nbsp;to determine how time delays in the mixing processes affect the rate of particle movement in water reservoirs.

Comparative studies on role of micro environmental factors onlactation length of Deoni cattle in their breeding areas

2016 ◽  
Author(s):  
B. N. Thorat ◽  
B. M. Thombre ◽  
A. T. Shinde
Keyword(s):  
Climatic Factors ◽  
Monsoon Season ◽  
Cold Season ◽  
Post Monsoon ◽  
Lactation Length ◽  
South West ◽  
South West Monsoon ◽  
Post Monsoon Season ◽  
Sources Of Variation ◽  
West Monsoon

In the present study pedigree records maintained at Cattle Cross Breeding Project, VNMKV, Parbhani (Maharashtra) for the period of 1995-2010 were utilized to study correlation of lactation length and climatic factors. The climatic parameters considered were temperature, relative humidity, wind velocity, sunshine hours and dry and wet bulb temperature along with THI. The data on monthly lactation length of cows calved during cold, hot, south-west monsoon and post monsoon seasons were considered. Correlation and multiple regression analysis was used to investigate various sources of variation in monthly lactation length. Monthly lactation length data were analyzed to ascertain the effect of climatic attributes and to know their association with lactation lengths. The average monthly lactation length was recorded as 220.21 + 6.75 days in Deoni cattle. It can be inferred that maximum lactation length was recorded during post monsoon season (240.94 + 11.26 days) followed by south-west monsoon season (222.28 + 9.00 days), cold season (218.67 + 8.25 days) and hot season (198.95 + 10.71 days), respectively..

scholarly journals Probabilistic Assessment of Monthly River Flow Discharge Using Copula And OSVR Approaches

2021 ◽  
Author(s):  
Mohammad Nazeri Tahroudi ◽  
Rasoul Mirabbasi ◽  
Yousef Ramezani ◽  
Farshad Ahmadi
Keyword(s):  
River Flow ◽  
Garch Model ◽  
Support Vector ◽  
Monthly Precipitation ◽  
Arch Models ◽  
Vector Autoregressive ◽  
Flow Discharge ◽  
Simulation Results ◽  
Hydrometric Station ◽  
Hydrology And Water Resources

Abstract Simulation of flow discharge based on monthly precipitation values as inputs is one of the important issues in hydrology and water resources studies, especially in areas where data with the shorter time scales are not available. In this study, the applicability of support vector regression (SVR) model optimized by Ant colony and Copula-GARCH algorithms was investigated and compared to simulate the flow discharge based on total monthly rainfall in Talezang Basin, Iran. Entropy theory was used to select a suitable meteorological station corresponding to a hydrometric station. The vector autoregressive model was also used as the base model in Copula-GARCH simulations. The correlation results of the studied paired variable confirmed the possibility of using copula-based models. The simulation results were evaluated using R2, Nash-Sutcliffe Efficiency (NSE) and root mean square error (RMSE) statistics. According to the 99% confidence intervals of the simulations, the accuracy of both models was confirmed. The simulation results showed that the Copula-GARCH model was more accurate than the optimized SVR (OSVR) model. Considering the 90% efficiency (NSE = 0.90) of Copula-GARCH approach, the results show a 36% improvement of RMSE statistics by Copula-GARCH model compared to OSVR model in simulating the flow discharge on a monthly scale. The results also showed that by combining nonlinear ARCH models with the copula-based simulations, the reliability of the simulation results increases, which was also confirmed using the violin plot. The results also showed an increase in the accuracy of the Copula-GARCH model at the minimum and maximum values of the data.

scholarly journals Temporal and Spatial Variations of Freshwater Reservoir Ages in the Loire River Watershed

Radiocarbon ◽  
2016 ◽  
Vol 58 (3) ◽  
pp. 549-563 ◽  
Author(s):  
C Coularis ◽  
N Tisnérat-Laborde ◽  
L Pastor ◽  
F Siclet ◽  
M Fontugne
Keyword(s):  
Inorganic Carbon ◽  
River Flow ◽  
Dissolved Inorganic Carbon ◽  
Dominant Factor ◽  
Reservoir Effect ◽  
Flow Discharge ◽  
Temporal And Spatial ◽  
Freshwater Reservoir ◽  
The Relationship ◽  
Loire River

AbstractIn order to map the freshwater reservoir effect (FRE) variability of the Loire River and its tributaries, spatial and temporal carbon isotope (13C and 14C) analyses of the dissolved inorganic carbon (DIC) were conducted. Sites were selected to represent the diversity of geological settings, soil type, and land use. Results show a large spatial variability of 14C FRE ranging between 135 and 2251±30 yr, objectively correlated to DIC contents and alkalinity. Deeper investigations of the relationship between 14C activity of DIC and environmental variables show that the geological substrate is the dominant factor in the 14C reservoir effect, and far more influential than the river flow discharge.

Sign in / Sign up

Export Citation Format

Share Document