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Applying a random parameters Negative Binomial Lindley model to examine multi-vehicle crashes along rural mountainous highways in Malaysia

Rusli R, Haque MM, Afghari AP, King M

Accid Anal Prev, 2018 Oct;119:80-90.
PMID: 30007211 DOI: 10.1016/j.aap.2018.07.006

Road safety in rural mountainous areas is a major concern as mountainous highways represent a complex road traffic environment due to complex topology and extreme weather conditions and are associated with more severe crashes compared to crashes along roads in flatter areas. The use of crash modelling to identify crash contributing factors along rural mountainous highways suffers from limitations in data availability, particularly in developing countries like Malaysia, and related challenges due to the presence of excess zero observations. To address these challenges, the objective of this study was to develop a safety performance function for multi-vehicle crashes along rural mountainous highways in Malaysia. To overcome the data limitations, an in-depth field survey, in addition to utilization of secondary data sources, was carried out to collect relevant information including roadway geometric factors, traffic characteristics, real-time weather conditions, cross-sectional elements, roadside features, and spatial characteristics. To address heterogeneity resulting from excess zeros, three specialized modelling techniques for excess zeros including Random Parameters Negative Binomial (RPNB), Random Parameters Negative Binomial - Lindley (RPNB-L) and Random Parameters Negative Binomial - Generalized Exponential (RPNB-GE) were employed. Results showed that the RPNB-L model outperformed the other two models in terms of prediction ability and model fit. It was found that heavy rainfall at the time of crash and the presence of minor junctions along mountainous highways increase the likelihood of multi-vehicle crashes, while the presence of horizontal curves along a steep gradient, the presence of a passing lane and presence of road delineation decrease the likelihood of multi-vehicle crashes. Findings of this study have significant implications for road safety along rural mountainous highways, particularly in the context of developing countries.

Matched MeSH terms: Rain*
Seasonality of Anopheles aconitus mosquitoes, a secondary vector of malaria, in an endemic village near the Malaysia-Thailand border

Rahman WA, Abu Hassan A, Adanan CR

Acta Trop, 1993 Dec;55(4):263-5.
PMID: 8147283
Matched MeSH terms: Rain
The prevalence of Plasmodium falciparum and P. vivax in relation to Anopheles maculatus densities in a Malaysian village

Rahman WA, Abu Hassan A, Adanan CR, Rashid MR

Acta Trop, 1993 Dec;55(4):231-5.
PMID: 8147279

Blood from most of the residents of a remote village in northern peninsular Malaysia, bordering Thailand, was examined for malaria parasites monthly for 1 year. Plasmodium vivax was the commonest infection, but P. falciparum and mixed infections also occurred. Monthly collections of the malaria vector, Anopheles maculatus showed a positive correlation between mosquito densities and malaria positivity in the human population and a negative correlation with rainfall.

Matched MeSH terms: Rain
Field and laboratory observations on Coquillettidia crassipes in relation to transmission of Brugia malayi in Peninsular Malaysia

Chiang GL, Samarawickrema WA, Mak JW, Cheong WH, Sulaiman I, Yap HH

Ann Trop Med Parasitol, 1986 Feb;80(1):117-21.
PMID: 2873797

Field observations were made on Coquillettidia crassipes during a study of Mansonia in a swamp forest ecotype in Tanjong Karang. There was an increase in abundance in July consistent with the increase in abundance of Mansonia and an increase in rainfall. The biting cycle showed a dramatic early peak during the period 1900-2000 hours. The probability of daily survival through one day for the first three gonotrophic cycles was 0.770, 0.722 and 0.759. Two of the 54 Cq. crassipes dissected were infective, with two and 25 L3 larvae of Brugia. Both subperiodic B. malayi and B. pahangi developed into L3 larvae in laboratory bred Cq. crassipes. The index of experimental infection was higher for B. pahangi. Mansonia bonneae and Ma. uniformis showed higher indices of experimental infection than Cq. crassipes for subperiodic B. malayi. It is concluded that in an endemic area with a high density of Cq. crassipes it could act as a secondary vector of Brugian filariasis.

Matched MeSH terms: Rain
Fulltext A time-series prediction model of acute myocardial infarction in northern of Iran: the risk of climate change and religious mourning

Sharif Nia H, Gorgulu O, Naghavi N, Froelicher ES, Fomani FK, Goudarzian AH, et al.

BMC Cardiovasc Disord, 2021 11 23;21(1):563.
PMID: 34814834 DOI: 10.1186/s12872-021-02372-0

BACKGROUND: Although various studies have been conducted on the effects of seasonal climate changes or emotional variables on the risk of AMI, many of them have limitations to determine the predictable model. The currents study is conducted to assess the effects of meteorological and emotional variables on the incidence and epidemiological occurrence of acute myocardial infarction (AMI) in Sari (capital of Mazandaran, Iran) during 2011-2018.
METHODS: In this study, a time series analysis was used to determine the variation of variables over time. All series were seasonally adjusted and Poisson regression analysis was performed. In the analysis of meteorological data and emotional distress due to religious mourning events, the best results were obtained by autoregressive moving average (ARMA) (5,5) model.
RESULTS: It was determined that average temperature, sunshine, and rain variables had a significant effect on death. A total of 2375 AMI's were enrolled. Average temperate (°C) and sunshine hours a day (h/day) had a statistically significant relationship with the number of AMI's (β = 0.011, P = 0.014). For every extra degree of temperature increase, the risk of AMI rose [OR = 1.011 (95%CI 1.00, 1.02)]. For every extra hour of sunshine, a day a statistically significant increase [OR = 1.02 (95% CI 1.01, 1.04)] in AMI risk occurred (β = 0.025, P = 0.001). Religious mourning events increase the risk of AMI 1.05 times more. The other independent variables have no significant effects on AMI's (P > 0.05).
CONCLUSION: Results demonstrate that sunshine hours and the average temperature had a significant effect on the risk of AMI. Moreover, emotional distress due to religious morning events increases AMI. More specific research on this topic is recommended.

Matched MeSH terms: Rain
Fulltext Seasonality of adult fragility fractures and association with weather: 12-year experience of a UK Fracture Liaison Service

Ogliari G, Ong T, Marshall L, Sahota O

Bone, 2021 Jun;147:115916.
PMID: 33737194 DOI: 10.1016/j.bone.2021.115916

PURPOSE: To investigate the monthly and seasonal variation in adult osteoporotic fragility fractures and the association with weather.
METHODS: 12-year observational study of a UK Fracture Liaison Service (outpatient secondary care setting). Database analyses of the records of adult outpatients aged 50 years and older with fragility fractures. Weather data were obtained from the UK's national Meteorological Office. In the seasonality analyses, we tested for the association between months and seasons (determinants), respectively, and outpatient attendances, by analysis of variance (ANOVA) and Tukey's test. In the meteorological analyses, the determinants were mean temperature, mean daily maximum and minimum temperature, number of days of rain, total rainfall and number of days of frost, per month, respectively. We explored the association of each meteorological variable with outpatient attendances, by regression models.
RESULTS: The Fracture Liaison Service recorded 25,454 fragility fractures. We found significant monthly and seasonal variation in attendances for fractures of the: radius or ulna; humerus; ankle, foot, tibia or fibula (ANOVA, all p-values <0.05). Fractures of the radius or ulna and humerus peaked in December and winter. Fractures of the ankle, foot, tibia or fibula peaked in July, August and summer. U-shaped associations were showed between each temperature parameter and fractures. Days of frost were directly associated with fractures of the radius or ulna (p-value <0.001) and humerus (p-value 0.002).
CONCLUSION: Different types of fragility fractures present different seasonal patterns. Weather may modulate their seasonality and consequent healthcare utilisation.

Matched MeSH terms: Rain
Fulltext Antifungal efficacy of crude aqueous weed extracts against pathogen of cocoa black pod rot

Nor Amerulah Nor Mohamad, Suhaida Salleh, Hamzah Abdul Aziz

Borneo Akademika, 2019;3(2):12-22.
MyJurnal

Black pod rot is the most economically important disease of cocoa in Malaysia which is
mainly caused by a highly polyphagous Phytophthora species, called Phytophthora palmivora.
The fungus could attack all parts of the cocoa plant organs and caused various diseases at
any growth stage from seedling until the mature stages, especially during raining season. The
application of synthetic fungicides has been widely recommended to manage the disease but
their repeated use had led to other problems such as environmental, human health and
development of fungicide resistance issues. This study isolated and identified Phytopththora
isolate from a cocoa pod sample based on micro-morphological characters. Besides, the
present investigation was undertaken to screen for the antifungal potency of different weed
extracts against the Phytophthora pathogen using poisoned food technique. The fungal isolate
was successfully recovered from pod tissues of clone PBC123 on 20% tomato juice agar
culture (20T). Only one out of ten weed extracts tested showed a significant in vitro inhibitory
effect towards mycelial growth of Phytophthora isolate, which was aqueous crude leaf extract
of Solanum torvum (42.68%). This study indicated that the potential of weed extracts in the
management of Phytophthora diseases, and may offer more natural, effective and economical
control methods.

Matched MeSH terms: Rain
Temporal changes in arthropod activity in tropical anthropogenic forests

Brandon-Mong GJ, Littlefair JE, Sing KW, Lee YP, Gan HM, Clare EL, et al.

Bull. Entomol. Res., 2018 Dec;108(6):792-799.
PMID: 29441836 DOI: 10.1017/S000748531800010X

Arthropod communities in the tropics are increasingly impacted by rapid changes in land use. Because species showing distinct seasonal patterns of activity are thought to be at higher risk of climate-related extirpation, global warming is generally considered a lower threat to arthropod biodiversity in the tropics than in temperate regions. To examine changes associated with land use and weather variables in tropical arthropod communities, we deployed Malaise traps at three major anthropogenic forests (secondary reserve forest, oil palm forest, and urban ornamental forest (UOF)) in Peninsular Malaysia and collected arthropods continuously for 12 months. We used metabarcoding protocols to characterize the diversity within weekly samples. We found that changes in the composition of arthropod communities were significantly associated with maximum temperature in all the three forests, but shifts were reversed in the UOF compared with the other forests. This suggests arthropods in forests in Peninsular Malaysia face a double threat: community shifts and biodiversity loss due to exploitation and disturbance of forests which consequently put species at further risk related to global warming. We highlight the positive feedback mechanism of land use and temperature, which pose threats to the arthropod communities and further implicates ecosystem functioning and human well-being. Consequently, conservation and mitigation plans are urgently needed.

Matched MeSH terms: Rain*
Ionic composition of rainwater at selected sites of Kuantan, Pahang, Malaysia: a preliminary study

Tay JH, Jaafar S, Mohd Tahir N

Bull Environ Contam Toxicol, 2014 Mar;92(3):329-33.
PMID: 24435136 DOI: 10.1007/s00128-014-1203-z

A short-term investigation on the chemical composition of rainwater was carried out at five selected sampling stations in Kuantan district, Pahang, Malaysia. Sampling of rainwater was conducted by event basis between September and November 2011. Rainwater samples were collected using polyethylene containers and the parameters measured were cations (sodium, potassium, ammonium, calcium and magnesium) and anions (chlorides, nitrates and sulphates). The average pH value for rainwater samples was 6.0 ± 0.57 in which most of the sampling sites exhibited pH values >5.6. Calcium and sulphate were the most abundant cation and anion, respectively, whilst the concentrations of other major ions varied according to sampling location.

Matched MeSH terms: Rain/chemistry*
Composition and source apportionment of surfactants in atmospheric aerosols of urban and semi-urban areas in Malaysia

Wahid NB, Latif MT, Suratman S

Chemosphere, 2013 Jun;91(11):1508-16.
PMID: 23336924 DOI: 10.1016/j.chemosphere.2012.12.029

This study was conducted to determine the composition and source apportionment of surfactant in atmospheric aerosols around urban and semi-urban areas in Malaysia based on ionic compositions. Colorimetric analysis was undertaken to determine the concentrations of anionic surfactants as Methylene Blue Active Substances (MBAS) and cationic surfactants as Disulphine Blue Active Substances (DBAS) using a UV spectrophotometer. Ionic compositions were determined using ion chromatography for cations (Na(+), NH4(+), K(+), Mg(2+), Ca(2+)) and anions (F(-), Cl(-), NO3(-), SO4(2-)). Principle component analysis (PCA) combined with multiple linear regression (MLR) were used to identify the source apportionment of MBAS and DBAS. Results indicated that the concentrations of surfactants at both sampling sites were dominated by MBAS rather than DBAS especially in fine mode aerosols during the southwest monsoon. Three main sources of surfactants were identified from PCA-MLR analysis for MBAS in fine mode samples particularly in Kuala Lumpur, dominated by motor vehicles, followed by soil/road dust and sea spray. Besides, for MBAS in coarse mode, biomass burning/sea spray were the dominant source followed by motor vehicles/road dust and building material.

Matched MeSH terms: Rain
Leaching of insecticides used in blueberry production and their toxicity to red worm

Hulbert D, Raja Jamil RZ, Isaacs R, Vandervoort C, Erhardt S, Wise J

Chemosphere, 2020 Feb;241:125091.
PMID: 31683442 DOI: 10.1016/j.chemosphere.2019.125091

Soil columns were collected from a blueberry field, and insecticide solutions were allowed to leach through these columns. Insecticides from four different chemical classes were applied at two different rates: the concentration at which the insecticides wash off blueberries under rainfall conditions and the labeled field rate at which they are sprayed. The soil columns were divided into thirds; top, middle and bottom. Soil bioassays using Eisenia foetida Savigny, as an indicator species, were set up to determine the toxicity of the insecticides at a top, middle and bottom layer of the soil column. The mass of E. foetida was also measured after the bioassay experiment was completed. The concentrations at which insecticides wash-off of blueberries from rainfall were not lethal to E. foetida. In order to support mortality data, insecticide residues were quantified in the soil layers for each insecticide. Under field rate leaching conditions, carbaryl showed the high levels of toxicity in the top and middle layers of soil suggesting that it has the highest risk to organisms from leaching. This study will help blueberry growers make informed decisions about insecticide use, which can help minimize contamination of the environment.

Matched MeSH terms: Rain
The siamang in Malaya. A field study of a primate in tropical rain forest

Chivers DJ

Contrib Primatol, 1974;4:1-335.
PMID: 4474071
Matched MeSH terms: Rain
Fulltext RNA-seq data of Oryza sativa cultivar Kuku Belang under PEG treatment

Toni B, Monfared HH, Mat Isa MN, Md Isa N, Ismail I, Zainal Z

Data Brief, 2017 Oct;14:260-266.
PMID: 28795103 DOI: 10.1016/j.dib.2017.07.043

Drought stress is the main abiotic factor affecting rice production. Rain-fed upland rice which is grown on unbounded fields and totally dependent on rainfall for moisture is more prone to drought stress compared to rice from other ecosystems. However, upland rice has adapted to this limited water condition, thus are more drought tolerant than rice from other ecosystems. We performed the first transcriptome sequencing of drought tolerant indica upland rice cultivar Kuku Belang to identify differentially expressed genes related to drought tolerance mechanism. Raw reads for non-treated and PEG-treated Oryza sativa subspecies indica cv. Kuku Belang were deposited in the NCBI SRA database with accession number SRP074520 (https://www.ncbi.nlm.nih.gov/sra?term=SRP074520).

Matched MeSH terms: Rain
Ant-gardens of tropical Asian rainforests

Kaufmann E, Maschwitz U

Naturwissenschaften, 2006 May;93(5):216-27.
PMID: 16544124

Ant-garden (AG) associations are systems of epiphytic plants and arboricolous (i.e., tree-living) ants, in which the ants build fragile carton nests containing organic material. They collect and incorporate seeds or fruits of epiphytes that then germinate and grow on the nest [sensu Corbara et al. (1999) 38:73-89]. The plant roots stabilize the nest carton. AGs have been well-known in the neotropics for more than 100 years. In contrast, reports on similar associations in the paleotropics are scarce so far. After discovering a first common AG system on giant bamboo [Kaufmann et al. (2001) 48:125-133], we started a large-scale survey for AGs in Peninsular Malaysia, Borneo, Java, and southern Thailand. A great variety of AG systems (altogether including 18 ant species and 51 plant species) was discovered and is described in the present paper. The high number of species participating in AG associations was reflected by a great variability in the specific appearances of the nest gardens. Frequently, further groups of organisms (e.g., hemipteran trophobionts, fungi) were also involved. Preference patterns of particular ant and epiphyte species for each other and for particular phorophytes (carrier trees) were detected. We integrate domatia-producing, so-called ant-house epiphytes in our study and compare their phases of establishment, as well as other characteristics, to "classical" AGs, coming to the conclusion that they should be regarded only as a special type of AG epiphyte and not as a separate ecological category.

Matched MeSH terms: Rain
Environmental geochemistry of the abandoned Mamut Copper Mine (Sabah) Malaysia

van der Ent A, Edraki M

Environ Geochem Health, 2018 Feb;40(1):189-207.
PMID: 27848090 DOI: 10.1007/s10653-016-9892-3

The Mamut Copper Mine (MCM) located in Sabah (Malaysia) on Borneo Island was the only Cu-Au mine that operated in the country. During its operation (1975-1999), the mine produced 2.47 Mt of concentrate containing approximately 600,000 t of Cu, 45 t of Au and 294 t of Ag, and generated about 250 Mt of overburden and waste rocks and over 150 Mt of tailings, which were deposited at the 397 ha Lohan tailings storage facility, 15.8 km from the mine and 980 m lower in altitude. The MCM site presents challenges for environmental rehabilitation due to the presence of large volumes of sulphidic minerals wastes, the very high rainfall and the large volume of polluted mine pit water. This indicates that rehabilitation and treatment is costly, as for example, exceedingly large quantities of lime are needed for neutralisation of the acidic mine pit discharge. The MCM site has several unusual geochemical features on account of the concomitant occurrence of acid-forming sulphide porphyry rocks and alkaline serpentinite minerals, and unique biological features because of the very high plant diversity in its immediate surroundings. The site hence provides a valuable opportunity for researching natural acid neutralisation processes and mine rehabilitation in tropical areas. Today, the MCM site is surrounded by protected nature reserves (Kinabalu Park, a World Heritage Site, and Bukit Hampuan, a Class I Forest Reserve), and the environmental legacy prevents de-gazetting and inclusion in these protected area in the foreseeable future. This article presents a preliminary geochemical investigation of waste rocks, sediments, secondary precipitates, surface water chemistry and foliar elemental uptake in ferns, and discusses these results in light of their environmental significance for rehabilitation.

Matched MeSH terms: Rain
Multivariate statistical techniques for the assessment of seasonal variations in surface water quality of pasture ecosystems

Ajorlo M, Abdullah RB, Yusoff MK, Halim RA, Hanif AH, Willms WD, et al.

Environ Monit Assess, 2013 Oct;185(10):8649-58.
PMID: 23604787 DOI: 10.1007/s10661-013-3201-8

This study investigates the applicability of multivariate statistical techniques including cluster analysis (CA), discriminant analysis (DA), and factor analysis (FA) for the assessment of seasonal variations in the surface water quality of tropical pastures. The study was carried out in the TPU catchment, Kuala Lumpur, Malaysia. The dataset consisted of 1-year monitoring of 14 parameters at six sampling sites. The CA yielded two groups of similarity between the sampling sites, i.e., less polluted (LP) and moderately polluted (MP) at temporal scale. Fecal coliform (FC), NO3, DO, and pH were significantly related to the stream grouping in the dry season, whereas NH3, BOD, Escherichia coli, and FC were significantly related to the stream grouping in the rainy season. The best predictors for distinguishing clusters in temporal scale were FC, NH3, and E. coli, respectively. FC, E. coli, and BOD with strong positive loadings were introduced as the first varifactors in the dry season which indicates the biological source of variability. EC with a strong positive loading and DO with a strong negative loading were introduced as the first varifactors in the rainy season, which represents the physiochemical source of variability. Multivariate statistical techniques were effective analytical techniques for classification and processing of large datasets of water quality and the identification of major sources of water pollution in tropical pastures.

Matched MeSH terms: Rain
Storm runoff quality and pollutant loading from commercial, residential, and industrial catchments in the tropic

Chow MF, Yusop Z, Shirazi SM

Environ Monit Assess, 2013 Oct;185(10):8321-31.
PMID: 23591675 DOI: 10.1007/s10661-013-3175-6

Information on the pollution level and the influence of hydrologic regime on the stormwater pollutant loading in tropical urban areas are still scarce. More local data are still required because rainfall and runoff generation processes in tropical environment are very different from the temperate regions. This study investigated the extent of urban runoff pollution in residential, commercial, and industrial catchments in the south of Peninsular Malaysia. Stormwater samples and flow rate data were collected from 51 storm events. Samples were analyzed for total suspended solids, 5-day biochemical oxygen demand, chemical oxygen demand, oil and grease (O&G), nitrate nitrogen (NO3-N), nitrite nitrogen, ammonia nitrogen, soluble reactive phosphorus, total phosphorus (TP), and zinc (Zn). It was found that the event mean concentrations (EMCs) of pollutants varied greatly between storm characteristics and land uses. The results revealed that site EMCs for residential catchment were lower than the published data but higher for the commercial and industrial catchments. All rainfall variables were negatively correlated with EMCs of most pollutants except for antecedent dry days (ADD). This study reinforced the earlier findings on the importance of ADD for causing greater EMC values with exceptions for O&G, NO3-N, TP, and Zn. In contrast, the pollutant loadings are influenced primarily by rainfall depth, mean intensity, and max 5-min intensity in all the three catchments. Overall, ADD is an important variable in multiple linear regression models for predicting the EMC values in the tropical urban catchments.

Matched MeSH terms: Rain
Composition and distribution of surfactants around Lake Chini, Malaysia

Latif MT, Wanfi L, Hanif NM, Roslan RN, Ali MM, Mushrifah I

Environ Monit Assess, 2012 Mar;184(3):1325-34.
PMID: 21472384 DOI: 10.1007/s10661-011-2043-5

This study aims to determine the composition of surfactants in the lake surface microlayer, rainwater, and atmospheric aerosols in the area surrounding Lake Chini, Pahang. Surfactants in the lake surface microlayer were taken from seven different stations around the lake, while samples of rainwater were taken from five different sampling stations. The samples of atmospheric aerosols were collected from the Lake Chini Research Centre which is in close proximity to the lake. The colorimetric analysis method was used to determine the composition and concentration of anionic surfactants as methylene blue active substances (MBAS) and cationic surfactants as disulphine blue active substances (DBAS). The concentration of anionic surfactants, as MBAS, in the surface microlayer ranged between 0.08 to 0.23 μmol L(-1), while the range of concentration of cationic surfactants as DBAS ranged from 0.09 to 0.11 μmol L(-1). The concentration of MBAS was higher in rainwater when compared to surfactants in the lake surface microlayer. The high concentration of surfactants in the fine mode of atmospheric aerosols suggests that natural and anthropogenic sources of surfactants contribute to the atmospheric surfactants.

Matched MeSH terms: Rain/chemistry
Monsoonal differences and probability distribution of PM(10) concentration

Md Yusof NF, Ramli NA, Yahaya AS, Sansuddin N, Ghazali NA, Al Madhoun W

Environ Monit Assess, 2010 Apr;163(1-4):655-67.
PMID: 19365611 DOI: 10.1007/s10661-009-0866-0

There are many factors that influence PM(10) concentration in the atmosphere. This paper will look at the PM(10) concentration in relation with the wet season (north east monsoon) and dry season (south west monsoon) in Seberang Perai, Malaysia from the year 2000 to 2004. It is expected that PM(10) will reach the peak during south west monsoon as the weather during this season becomes dry and this study has proved that the highest PM(10) concentrations in 2000 to 2004 were recorded in this monsoon. Two probability distributions using Weibull and lognormal were used to model the PM(10) concentration. The best model used for prediction was selected based on performance indicators. Lognormal distribution represents the data better than Weibull distribution model for 2000, 2001, and 2002. However, for 2003 and 2004, Weibull distribution represents better than the lognormal distribution. The proposed distributions were successfully used for estimation of exceedences and predicting the return periods of the sequence year.

Matched MeSH terms: Rain*
Spatial and statistical trend characteristics of rainfall erosivity (R) in upper catchment of Baram River, Borneo

Vijith H, Dodge-Wan D

Environ Monit Assess, 2019 Jul 13;191(8):494.
PMID: 31302794 DOI: 10.1007/s10661-019-7604-z

The upper catchment region of the Baram River in Sarawak (Malaysian Borneo) is undergoing severe land degradation due to soil erosion. Heavy rainfall with high erosive power has led to a number of soil erosion hotspots. The goal of the present study is to generate an understanding about the spatial characteristics of seasonal and annual rainfall erosivity (R), which not only control sediment delivery from the region but also determine the quantity of material potentially eroded. Mean annual rainfall and rainfall erosivity range from 2170 to 5167 mm and 1632 to 5319 MJ mm ha-1 h-1 year-1, respectively. Seasonal rainfall and rainfall erosivity range from 848 to 1872 mm and 558 to 1883 MJ mm ha-1 h-1 year-1 for the southwest (SW) monsoon, 902 to 2200 mm and 664 to 2793 MJ mm ha-1h-1year-1 for the northeast (NE) monsoon and 400 to 933 mm and 331 to 1075 MJ mm ha-1 h-1 year-1 during the inter-monsoon (IM) period. Linear regression, Spearman's Rho and Mann Kendall tests were applied. Considering the regional mean rainfall erosivity in the study area, all the methods show an overall non-significant decreasing trend (- 9.34, - 0.25 and - 0.30 MJ mm ha-1 h-1 year-1, respectively for linear regression, Spearman's Rho and Mann Kendall tests). However, during SW monsoon and IM periods, rainfall erosivity showed a non-significant decreasing trend (- 25.45, - 0.52, - 0.40, and - 8.86, - 1.07, - 0.77 MJ mm ha-1 h-1 year-1, respectively) whereas in NE, monsoon season erosivity showed a non-significant increasing trend (14.90, 1.59 and 1.60 MJ mm ha-1 h-1 year-1, respectively). The mean erosivity density ranges from 0.77 to 1.38 MJ ha-1 h-1 year-1 and shows decreasing trend. Spatial distribution pattern of erosivity density indicates significantly higher occurrence of erosive rainfall in the lower elevation portion of the study area. The spatial pattern of mean rainfall erosivity trends (linear, Spearman's Rho and Mann Kendall) suggests that the study area can be divided into two zones with increasing rainfall erosivity trends in the northern zone and decreasing trends in the southern zone. These results can be used to plan conservation measures to reduce sediment delivery from localized soil erosion hotspots.

Matched MeSH terms: Rain*

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