Study of the differences in soil properties between the dry season and rainy season in the Mun River Basin

CATENA ◽  
2019 ◽  
Vol 182 ◽  
pp. 104103 ◽  
Author(s):  
Chunsheng Wu ◽  
Gaohuan Liu ◽  
Guoxia Ma ◽  
Qingsheng Liu ◽  
Fang Yu ◽  
...  
Keyword(s):  
Soil Properties ◽  
River Basin ◽  
Rainy Season ◽  
Dry Season

scholarly journals Diversity and habitat preference of aquatic insects along the longitudinal gradient of the Macaé River basin, Rio de Janeiro, Brazil

2001 ◽  
Vol 61 (2) ◽  
pp. 249-258 ◽  
Author(s):  
D. F. BAPTISTA ◽  
D. F. BUSS ◽  
L. F. M. DORVILLÉ ◽  
J. L. NESSIMIAN
Keyword(s):  
River Basin ◽  
Aquatic Insects ◽  
Habitat Preference ◽  
Rainy Season ◽  
Rio De Janeiro ◽  
Dry Season ◽  
Longitudinal Gradient ◽  
Order Stream ◽  
Surber Sampler ◽  
Janeiro State

Diversity and habitat preference of macroinvertebrates were studied in Macaé River basin, Rio de Janeiro State, Brazil, along its longitudinal gradient. We selected stream reaches corresponding to 1st, 2nd, 4th, 5th and 6th orders. A Surber sampler was used to collect four macroinvertebrates samples of each substrate (sand, litter in pool areas, stones, and litter in riffle areas) during the three sampling periods, defined based on the rain regime: April (end of the rainy season), July (dry season), and October (beginning of the rainy season). We identified 46,431 specimens corresponding to 117 taxa. Analysis of diversity numbers (both for family or genus level) indicated that all insect taxonomic orders had higher numbers on 2nd order stream reach, except for Ephemeroptera, on 4th order. However when considering morph-species taxonomic level, the higher diversity number occurred on 4th order stream. The highest richness and diversity numbers were found at the dry season. Considering habitat preference, both litter in pool areas and litter in riffle areas had the highest faunal richness.

scholarly journals Distribution Characteristics and Seasonal Variation of Soil Nutrients in the Mun River Basin, Thailand

2018 ◽  
Vol 15 (9) ◽  
pp. 1818 ◽  
Author(s):  
Zhonghe Zhao ◽  
Gaohuan Liu ◽  
Qingsheng Liu ◽  
Chong Huang ◽  
He Li ◽  
...  
Keyword(s):  
Seasonal Variation ◽  
River Basin ◽  
Soil Nutrients ◽  
Rainy Season ◽  
Ph Value ◽  
Soil Nutrient ◽  
Nutrient Content ◽  
Dry Season ◽  
Strong Variation ◽  
Geostatistical Methods

Based on soil sampling data from the dry season and the rainy season, the spatial heterogeneity and spatial pattern of soil nutrients in the Mun River Basin, Thailand, were studied and the seasonal variation in soil nutrients was analyzed using classical statistical methods and geostatistical methods. The soil nutrient content in the Mun Basin showed moderate and strong variations, and the descending order of soil variability was as follows: available phosphorous (AP) > electric conductivity (EC) > soil organic matter (SOM) > total nitrogen (TN) > pH value in the dry season, with AP showing strong variation, and EC > AP > SOM > TN > pH in the rainy season, with EC showing strong variation. Different soil nutrients and different soil properties had different spatial variation characteristics, and their corresponding best-fitting models were also different. Based on the nugget (C0), sill (C0 + C), and range (A), spatial analysis was performed for the soil nutrients, pH, and EC in the dry season and in the rainy season. Analysis based on kriging spatial interpolation data showed that pH, SOM, TN, and EC had convex or concave distributions, whereas AP had a patchy distribution. Terrain, vegetation, and human disturbance are the main factors that contribute to the differences in the soil nutrient pattern of the Mun River Basin.

scholarly journals Heavy Metals in Water, Soils and Sediments of La Villa River Basin- Panama

2021 ◽  
pp. 1-12
Author(s):  
José Villarreal Núñez ◽  
Adolfo Santo Pineda ◽  
Jhon Villalaz Pérez ◽  
Iván Ramos Zachrisson
Keyword(s):  
Heavy Metals ◽  
River Basin ◽  
Water Samples ◽  
Rainy Season ◽  
Anthropogenic Activities ◽  
Great Influence ◽  
Dry Season ◽  
High Concentration ◽  
South Central ◽  
Rectangular Area

Determine the concentration of heavy metals in water, sediments, and crops within the La Villa river basin, Herrera and Los Santos provinces, republic of Panama. La Villa river Basin, south central of Panama, in the rainy season of 2016 (May to November) and in the dry season of 2017 (December to April). Twenty two sediments and water samples were taken using the systematic method which consists of selecting sampling points at uniform distances and crops in upper, middle and lower basin. The selected sampling was confined to a preferably rectangular area of 10.0 m x 30.0 m, on which the sub-samples were taken with a number of 15 on each grid, at 0.20m depth. For collecting the water samples, a rod with a clean plastic bottle was introduced against the current of the river. The digestion of sediments and crops to determine the concentration of heavy metals (As, Pb, Cr, Ni, Cu, Mn, Zn and Cd) was carried out according to USEPA (25) method (3051A) (SW-846). In the sediments, in the rainy season, Cu (upper and lower basin) and Mn (all levels) values were found above the USEPA Standards. In the dry season, high values of Mn were found in the middle and lower basin, Cr in the upper and lower basin and As in all areas of the basin. In the rainy and dry seasons, high levels of Mn, Zn, Cr, Cd and Pb were found in the waters of the rivers that make up the basin. The main crops at each height of the basin were analyzed, determining high levels of As and Cr in the upper basin, in the middle and lower basin Cr and Cd. It is necessary to monitor the concentration of heavy metals in sediments of La Villa river basin because 90% of the agrochemicals that enter the country is destined for agriculture. Each Panamanian consumes (does not ingest) 3 kg of agrochemicals annually, exceeding six times the amount used in Central America.  Due to their geological origin, these soils are rich in copper, manganese and arsenic, latter being associated with iron oxides and sulfides but there is also great influence of anthropogenic activities, agriculture and industries. Some metals such as lead and arsenic showed low solubility in water but showed high concentration in sediments. Chromium and cadmium present in crops come from water.

STUDI BIONOMIK VEKTOR MALARIA DI KECAMATAN KALIBAWANG, KULONPROGO

2018 ◽  
Vol 4 (2) ◽  
Author(s):  
Sardjito Eko Windarso dkk
Keyword(s):  
Land Use ◽  
Malaria Vector ◽  
Rainy Season ◽  
Dry Season ◽  
Physical Factors ◽  
Mosquito Vector ◽  
Anopheles Species ◽  
Commercial Farming ◽  
Study Results ◽  
Dry And Rainy Seasons

The increasing of malaria cases in recent years at Kecamatan Kalibawang has been suspected correspond with the conversion of farming land-use which initiated in 1993. Four years after the natural vegetation in this area were changed become cocoa and coffee commercial farming estates, the number of malaria cases in 1997 rose more than six times, and in 2000 it reached 6085. This study were aimed to observe whether there were any differences in density and diversity of Anopheles as malaria vector between the cocoa and mix farming during dry and rainy seasons. The results of the study are useful for considering the appropriate methods, times and places for mosquito vector controlling. The study activities comprised of collecting Anopheles as well as identifying the species to determine the density and diversity of the malaria vector. Both activities were held four weeks in dry season and four weeks in rainy season. The mea-surement of physical factors such as temperature, humidity and rainfall were also conducted to support the study results. Four dusuns which meet the criteria and had the highest malaria cases were selected as study location. Descriptively, the results shows that the number of collected Anopheles in cocoa farming were higher compared with those in mix horticultural farming; and the number of Anopheles species identifi ed in cocoa farming were also more varied than those in the mix horticultural farming.Key words: bionomik vektor malaria, anopheles,

scholarly journals Understanding variability in greenhouse gas emission estimates of smallholder dairy farms in Indonesia

2021 ◽  
Author(s):  
Titis Apdini ◽  
Windi Al Zahra ◽  
Simon J. Oosting ◽  
Imke J. M. de Boer ◽  
Marion de Vries ◽  
...  
Keyword(s):  
Greenhouse Gas ◽  
Rainy Season ◽  
Greenhouse Gas Emission ◽  
Dairy Farms ◽  
Dry Season ◽  
Enteric Fermentation ◽  
Tropical Regions ◽  
Population Mean ◽  
Smallholder Dairy ◽  
Smallholder Dairy Farms

Abstract Purpose Life cycle assessment studies on smallholder farms in tropical regions generally use data that is collected at one moment in time, which could hamper assessment of the exact situation. We assessed seasonal differences in greenhouse gas emissions (GHGEs) from Indonesian dairy farms by means of longitudinal observations and evaluated the implications of number of farm visits on the variance of the estimated GHGE per kg milk (GHGEI) for a single farm, and the population mean. Methods An LCA study was done on 32 smallholder dairy farms in the Lembang district area, West Java, Indonesia. Farm visits (FVs) were performed every 2 months throughout 1 year: FV1–FV3 (rainy season) and FV4–FV6 (dry season). GHGEs were assessed for all processes up to the farm-gate, including upstream processes (production and transportation of feed, fertiliser, fuel and electricity) and on-farm processes (keeping animals, manure management and forage cultivation). We compared means of GHGE per unit of fat-and-protein-corrected milk (FPCM) produced in the rainy and the dry season. We evaluated the implication of number of farm visits on the variance of the estimated GHGEI, and on the variance of GHGE from different processes. Results and discussion GHGEI was higher in the rainy (1.32 kg CO2-eq kg−1 FPCM) than in the dry (0.91 kg CO2-eq kg−1 FPCM) season (P < 0.05). The between farm variance was 0.025 kg CO2-eq kg−1 FPCM in both seasons. The within farm variance in the estimate for the single farm mean decreased from 0.69 (1 visit) to 0.027 (26 visits) kg CO2-eq kg−1 FPCM (rainy season), and from 0.32 to 0.012 kg CO2-eq kg−1 FPCM (dry season). The within farm variance in the estimate for the population mean was 0.02 (rainy) and 0.01 (dry) kg CO2-eq kg−1 FPCM (1 visit), and decreased with an increase in farm visits. Forage cultivation was the main source of between farm variance, enteric fermentation the main source of within farm variance. Conclusions The estimated GHGEI was significantly higher in the rainy than in the dry season. The main contribution to variability in GHGEI is due to variation between observations from visits to the same farm. This source of variability can be reduced by increasing the number of visits per farm. Estimates for variation within and between farms enable a more informed decision about the data collection procedure.

scholarly journals Directional Distance Function Technical Efficiency of Chili Production in Thailand

2021 ◽  
Vol 13 (2) ◽  
pp. 741
Author(s):  
Wirat Krasachat ◽  
Suthathip Yaisawarng
Keyword(s):  
Distance Function ◽  
Rainy Season ◽  
Sample Selection ◽  
Agricultural Practices ◽  
Directional Distance Function ◽  
Dry Season ◽  
Small Samples ◽  
Function Technique ◽  
Security Problem ◽  
Gap Technology

To overcome the challenging food safety and security problem, in 2003, the Thai government initiated ‘Good Agricultural Practices’ (GAP) technology. This paper used a sample of 107 small chili farms from the Chiyaphoom province for the 2012 crop year, and data envelopment analysis (DEA) meta-frontier directional distance function technique to answer two questions: (1) Are GAP-adopting farms, on average, more efficient than conventional farms? (2) Does access to GAP technology affect farmers’ decisions to adopt GAP technology? We also developed an ‘indirect’ approach to reduce the potential sample selection bias for small samples. For the dry-season subsample, GAP farms were more technically efficient when compared with non-GAP farms. These dry-season non-GAP farms may not adopt the GAP method because they have limited access to GAP technology. For the rainy-season subsample, on average, GAP farms were more efficient than non-GAP farms at the 5% level. Access to the GAP technology is not a possible reason for non-GAP rainy season farms to not adopt the GAP technology. To enable sustainable development, government agencies and nongovernmental organizations (NGOs) must develop and implement appropriate educational and training workshops to promote and assist GAP technology adoption for chili farms in Thailand.

scholarly journals Application of Sentinel-1 and-2 Images in Measuring the Deformation of Kuh-e-Namak (Dashti) Namakier, Iran

2021 ◽  
Vol 13 (4) ◽  
pp. 785
Author(s):  
Sen Zhang ◽  
Qigang Jiang ◽  
Chao Shi ◽  
Xitong Xu ◽  
Yundi Gong ◽  
...  
Keyword(s):  
Synthetic Aperture Radar ◽  
Rock Salt ◽  
Rainy Season ◽  
Surface Deformation ◽  
Meteorological Data ◽  
Dry Season ◽  
Synthetic Aperture ◽  
Advantages And Disadvantages ◽  
Sbas Insar ◽  
Aperture Radar

Kuh-e-Namak (Dashti) namakier is one of the most active salt diapirs along the Zagros fold–thrust belt in Iran. Its surface deformation should be measured to estimate its long-term kinematics. Ten Sentinel-2 optical images acquired between October 2016 and December 2019 were processed by using Co-Registration of Optically Sensed Images and Correlation (COSI-Corr) method. Forty-seven Sentinel-1 ascending Synthetic Aperture Radar (SAR) images acquired between April 2017 and December 2019 were processed by using Small Baseline Subset Synthetic Aperture Radar Interferometry (SBAS-InSAR) method. The deformation of Kuh-e-Namak (Dashti) namakier was measured using both methods. Then, meteorological data were utilized to explore the relationship between the kinematics of the namakier and weather conditions and differences in macrodeformation behavior of various rock salt types. The advantages and disadvantages of COSI-Corr and SBAS-InSAR methods in measuring the deformation of the namakier were compared. The results show that: (1) The flank subsides in the dry season and uplifts in the rainy season, whereas the dome subsides in the rainy season and uplifts in the dry season. Under extreme rainfall conditions, the namakier experiences permanent plastic deformation. (2) The “dirty” rock salt of the namakier is more prone to flow than the “clean” rock salt in terms of macrodeformation behavior. (3) In the exploration of the kinematics of the namakier via the two methods, COSI-Corr is superior to SBAS-InSAR on a spatial scale, but the latter is superior to the former on a time scale.

scholarly journals Seasonal Differences in Cyclospora cayetanensis Prevalence in Colombian Indigenous People

2021 ◽  
Vol 9 (3) ◽  
pp. 627
Author(s):  
Hagen Frickmann ◽  
Juliane Alker ◽  
Jessica Hansen ◽  
Juan Carlos Dib ◽  
Andrés Aristizabal ◽  
...  
Keyword(s):  
Indigenous People ◽  
Rainy Season ◽  
Gastrointestinal Symptoms ◽  
Dry Season ◽  
Seasonal Effects ◽  
Chain Reaction ◽  
Resource Limited Settings ◽  
Resource Limited ◽  
Stool Samples ◽  
Polymerase Chain

Fecal-orally transmitted cyclosporiasis is frequent in remote resource-limited settings in Central and South America with poor hygiene conditions. In this study, we aimed at assessing seasonal effects on the epidemiology of colonization or infection with C. cayetanensis in Colombian indigenous people living under very restricted conditions. In the rainy season between July and November and in the dry season between January and April, stool samples from indigenous people with and without gastrointestinal symptoms were collected and screened for C. cayetanensis applying in-house real-time polymerase chain reaction (PCR). In the rainy season and in the dry season, positive PCR results were observed for 11.8% (16/136) and 5.1% (15/292), respectively, with cycle threshold (Ct) values of 30.6 (±3.4) and 34.4 (±1.6), respectively. Despite higher parasite loads in the rainy season, fewer individuals (2/16, 12.5%) reported gastrointestinal symptoms compared to the dry season (6/15, 40%). In conclusion, considerable prevalence of C. cayetanensis in Colombian indigenous people persists in the dry season. Low proportions of gastrointestinal symptoms along with higher parasite loads make colonization likely rather than infection.

scholarly journals Nocturnal Boundary Layer Erosion Analysis in the Amazon Using Large-Eddy Simulation during GoAmazon Project 2014/5

Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 240
Author(s):  
Rayonil Carneiro ◽  
Gilberto Fisch ◽  
Theomar Neves ◽  
Rosa Santos ◽  
Carlos Santos ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Large Eddy Simulation ◽  
Rainy Season ◽  
Nocturnal Boundary Layer ◽  
Enso Event ◽  
Dry Season ◽  
Dry Period ◽  
Additional Energy ◽  
Eddy Simulation ◽  
Large Eddy

This study investigated the erosion of the nocturnal boundary layer (NBL) over the central Amazon using a high-resolution model of large-eddy simulation (LES) named PArallel Les Model (PALM) and observational data from Green Ocean Amazon (GoAmazon) project 2014/5. This data set was collected during four intense observation periods (IOPs) in the dry and rainy seasons in the years 2014 (considered a typical year) and 2015, during which an El Niño–Southern Oscillation (ENSO) event predominated and provoked an intense dry season. The outputs from the PALM simulations represented reasonably well the NBL erosion, and the results showed that it has different characteristics between the seasons. During the rainy season, the IOPs exhibited slow surface heating and less intense convection, which resulted in a longer erosion period, typically about 3 h after sunrise (that occurs at 06:00 local time). In contrast, dry IOPs showed more intensive surface warming with stronger convection, resulting in faster NBL erosion, about 2 h after sunrise. A conceptual model was derived to investigate the complete erosion during sunrise hours when there is a very shallow mixed layer formed close to the surface and a stable layer above. The kinematic heat flux for heating this layer during the erosion period showed that for the rainy season, the energy emitted from the surface and the entrainment was not enough to fully heat the NBL layer and erode it. Approximately 30% of additional energy was used in the system, which could come from the release of energy from biomass. The dry period of 2014 showed stronger heating, but it was also not enough, requiring approximately 6% of additional energy. However, for the 2015 dry period, which was under the influence of the ENSO event, it was shown that the released surface fluxes were sufficient to fully heat the layer. The erosion time of the NBL probably influenced the development of the convective boundary layer (CBL), wherein greater vertical development was observed in the dry season IOPs (~1500 m), while the rainy season IOPs had a shallower layer (~1200 m).

Sign in / Sign up

Export Citation Format

Share Document