Displaying publications 501 - 520 of 617 in total

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  1. Fulltext The atmospheric chemistry of trace gases and particulate matter emitted by different land uses in Borneo
    MacKenzie AR, Langford B, Pugh TA, Robinson N, Misztal PK, Heard DE, et al.
    Philos Trans R Soc Lond B Biol Sci, 2011 Nov 27;366(1582):3177-95.
    PMID: 22006961 DOI: 10.1098/rstb.2011.0053
    We report measurements of atmospheric composition over a tropical rainforest and over a nearby oil palm plantation in Sabah, Borneo. The primary vegetation in each of the two landscapes emits very different amounts and kinds of volatile organic compounds (VOCs), resulting in distinctive VOC fingerprints in the atmospheric boundary layer for both landscapes. VOCs over the Borneo rainforest are dominated by isoprene and its oxidation products, with a significant additional contribution from monoterpenes. Rather than consuming the main atmospheric oxidant, OH, these high concentrations of VOCs appear to maintain OH, as has been observed previously over Amazonia. The boundary-layer characteristics and mixing ratios of VOCs observed over the Borneo rainforest are different to those measured previously over Amazonia. Compared with the Bornean rainforest, air over the oil palm plantation contains much more isoprene, monoterpenes are relatively less important, and the flower scent, estragole, is prominent. Concentrations of nitrogen oxides are greater above the agro-industrial oil palm landscape than over the rainforest, and this leads to changes in some secondary pollutant mixing ratios (but not, currently, differences in ozone). Secondary organic aerosol over both landscapes shows a significant contribution from isoprene. Primary biological aerosol dominates the super-micrometre aerosol over the rainforest and is likely to be sensitive to land-use change, since the fungal source of the bioaerosol is closely linked to above-ground biodiversity.
    Matched MeSH terms: Agriculture*
  2. Effects of pesticide use on semen quality among farmers in rural areas of Sabah, Malaysia
    Hossain F, Ali O, D'Souza UJ, Naing DK
    J Occup Health, 2010;52(6):353-60.
    PMID: 20924153
    OBJECTIVES: To determine the relationship between semen quality and exposure to pesticide residues.

    METHODS: A cross-sectional study was conducted among male farmers from 3 different communities in Sabah, Malaysia. A total of 152 farmers participated in this study of whom 62 farmers had been exposed to either paraquat or malathion or both to varying extents. Questionnaires were designed to record a history of pesticides exposure and other potential risk factors among farmers. All semen samples were collected, processed and analyzed by qualified personnel based on WHO guidelines. Volume, pH, sperm concentration, motility, morphology and WBC count were examined and recorded. The association between pesticide exposure and semen parameters was highly significant.

    RESULTS: The mean values of volume, pH, sperm concentration, motility, and WBC count were significantly less in the exposed group than in compared with the non-exposed group, with p<0.005. Those who were exposed to pesticides had greater risk of having abnormal semen parameters than those in with the non exposed group, with p values of less than 0.05. The comparison between semen qualities such as lower sperm count, motility and higher percentage of sperm abnormality of those exposed to different types of pesticides (paraquat and malathion) showed no significant differences.

    CONCLUSION: The results showed a significant decline in semen quality with a decline in sperm count, motility and higher percent of teratospermia among subjects with pesticide exposure, and those who were exposed to pesticides had significantly 3 to 9 times greater risk of having abnormal semen parameters.

    Matched MeSH terms: Agriculture*
  3. Occurrence of thermophilic Campylobacter spp. contamination on vegetable farms in Malaysia
    Chai LC, Ghazali FM, Bakar FA, Lee HY, Suhaimi LR, Talib SA, et al.
    J Microbiol Biotechnol, 2009 Nov;19(11):1415-20.
    PMID: 19996696
    The aim of the present study was to examine the prevalence of thermophilic Campylobacter spp. (Campylobacter jejuni and Campylobacter coli) in soil, poultry manure, irrigation water, and freshly harvested vegetables from vegetable farms in Malaysia. C. jejuni was detected in 30.4% and 2.7% of the soil samples, 57.1% and 0% of the manure samples, and 18.8% and 3% of the vegetable samples from farm A and farm B, respectively, when using the MPNPCR method. Campylobacter spp. was not found in any of the irrigation water samples tested. Therefore, the present results indicate that the aged manure used by farm A was more contaminated than the composted manure used by farm B. Mostly, the leafy and root vegetables were contaminated. C. coli was not detected in any of the samples tested in the current study. Both farms tested in this study were found to be contaminated by campylobacters, thereby posing a potential risk for raw vegetable consumption in Malaysia. The present results also provide baseline data on Campylobacter contamination at the farm level.
    Matched MeSH terms: Agriculture*
  4. Green reconstruction of the tsunami-affected areas in India using the integrated coastal zone management concept
    Sonak S, Pangam P, Giriyan A
    J Environ Manage, 2008 Oct;89(1):14-23.
    PMID: 17544565
    A tsunami, triggered by a massive undersea earthquake off Sumatra in Indonesia, greatly devastated the lives, property and infrastructure of coastal communities in the coastal states of India, Andaman and Nicobar Islands, Indonesia, Sri Lanka, Malaysia and Thailand. This event attracted the attention of environmental managers at all levels, local, national, regional and global. It also shifted the focus from the impact of human activities on the environment to the impacts of natural hazards. Recovery/reconstruction of these areas is highly challenging. A clear understanding of the complex dynamics of the coast and the types of challenges faced by the several stakeholders of the coast is required. Issues such as sustainability, equity and community participation assume importance. The concept of ICZM (integrated coastal zone management) has been effectively used in most parts of the world. This concept emphasizes the holistic assessment of the coast and a multidisciplinary analysis using participatory processes. It integrates anthropocentric and eco-centric approaches. This paper documents several issues involved in the recovery of tsunami-affected areas and recommends the application of the ICZM concept to the reconstruction efforts.
    Matched MeSH terms: Agriculture/legislation & jurisprudence
  5. Fulltext Organic cultivation practices enhanced antioxidant activities and secondary metabolites in giant granadilla (Passiflora quadrangularis L.)
    Ramaiya SD, Lee HH, Xiao YJ, Shahbani NS, Zakaria MH, Bujang JS
    PLoS One, 2021;16(7):e0255059.
    PMID: 34310644 DOI: 10.1371/journal.pone.0255059
    Passiflora quadrangularis L. belongs to the family Passifloraceae which bears larger fruit with edible juicy mesocarp and pulp known as a good source of phytochemicals. Cultivation and plant management practices are known to influence the phytochemical compositions of agricultural produce. This study aimed to examine the influence of the cultivation practices on the antioxidant activities and secondary metabolites of the organically and conventionally grown P. quadrangularis. Findings revealed organically treated P. quadrangularis plants showed enhancement in their antioxidant properties and secondary metabolites profiles. Among the plant parts, leaves of P. quadrangularis grown organically possessed higher antioxidant activities compared to the conventional in all assays evaluated. The antioxidant activities in the edible parts of the P. quadrangularis fruit have also been enhanced through organic cultivation with significantly higher total phenolic content and DPPH in mesocarp, and the pulp showed higher total flavonoid content, DPPH and FRAP. This observation is supported by a higher level of vitamins and secondary metabolites in the samples. The secondary metabolites profile showed mesocarps were phenolic rich, the pulps were flavonoids rich while leaves showed good composition of phenolics, flavonoids and terpenoids with outstanding antioxidant activities. The common secondary metabolites for organically produced P. quadrangularis in different plant parts include 2-isopropyl-3-methoxycinnamic acid (mesocarp and pulp), myricetin isomers (pulp and leaves), and malvidin-3-O-arabinoside isomers (pulp and leaves). This study confirmed that organic cultivated P. quadrangularis possessed higher antioxidant activities contributed by its vitamins and secondary metabolites.
    Matched MeSH terms: Organic Agriculture*
  6. Fulltext Nitrogen management is essential to prevent tropical oil palm plantations from causing ground-level ozone pollution
    Hewitt CN, MacKenzie AR, Di Carlo P, Di Marco CF, Dorsey JR, Evans M, et al.
    Proc Natl Acad Sci U S A, 2009 Nov 3;106(44):18447-51.
    PMID: 19841269 DOI: 10.1073/pnas.0907541106
    More than half the world's rainforest has been lost to agriculture since the Industrial Revolution. Among the most widespread tropical crops is oil palm (Elaeis guineensis): global production now exceeds 35 million tonnes per year. In Malaysia, for example, 13% of land area is now oil palm plantation, compared with 1% in 1974. There are enormous pressures to increase palm oil production for food, domestic products, and, especially, biofuels. Greater use of palm oil for biofuel production is predicated on the assumption that palm oil is an "environmentally friendly" fuel feedstock. Here we show, using measurements and models, that oil palm plantations in Malaysia directly emit more oxides of nitrogen and volatile organic compounds than rainforest. These compounds lead to the production of ground-level ozone (O(3)), an air pollutant that damages human health, plants, and materials, reduces crop productivity, and has effects on the Earth's climate. Our measurements show that, at present, O(3) concentrations do not differ significantly over rainforest and adjacent oil palm plantation landscapes. However, our model calculations predict that if concentrations of oxides of nitrogen in Borneo are allowed to reach those currently seen over rural North America and Europe, ground-level O(3) concentrations will reach 100 parts per billion (10(9)) volume (ppbv) and exceed levels known to be harmful to human health. Our study provides an early warning of the urgent need to develop policies that manage nitrogen emissions if the detrimental effects of palm oil production on air quality and climate are to be avoided.
    Matched MeSH terms: Agriculture*
  7. Fulltext Plant Growth-Promoting Rhizobacteria Inoculation to Enhance Vegetative Growth, Nitrogen Fixation and Nitrogen Remobilisation of Maize under Greenhouse Conditions
    Kuan KB, Othman R, Abdul Rahim K, Shamsuddin ZH
    PLoS One, 2016;11(3):e0152478.
    PMID: 27011317 DOI: 10.1371/journal.pone.0152478
    Plant growth-promoting rhizobacteria (PGPR) may provide a biological alternative to fix atmospheric N2 and delay N remobilisation in maize plant to increase crop yield, based on an understanding that plant-N remobilisation is directly correlated to its plant senescence. Thus, four PGPR strains were selected from a series of bacterial strains isolated from maize roots at two locations in Malaysia. The PGPR strains were screened in vitro for their biochemical plant growth-promoting (PGP) abilities and plant growth promotion assays. These strains were identified as Klebsiella sp. Br1, Klebsiella pneumoniae Fr1, Bacillus pumilus S1r1 and Acinetobacter sp. S3r2 and a reference strain used was Bacillus subtilis UPMB10. All the PGPR strains were tested positive for N2 fixation, phosphate solubilisation and auxin production by in vitro tests. In a greenhouse experiment with reduced fertiliser-N input (a third of recommended fertiliser-N rate), the N2 fixation abilities of PGPR in association with maize were determined by 15N isotope dilution technique at two harvests, namely, prior to anthesis (D50) and ear harvest (D65). The results indicated that dry biomass of top, root and ear, total N content and bacterial colonisations in non-rhizosphere, rhizosphere and endosphere of maize roots were influenced by PGPR inoculation. In particular, the plants inoculated with B. pumilus S1r1 generally outperformed those with the other treatments. They produced the highest N2 fixing capacity of 30.5% (262 mg N2 fixed plant-1) and 25.5% (304 mg N2 fixed plant-1) of the total N requirement of maize top at D50 and D65, respectively. N remobilisation and plant senescence in maize were delayed by PGPR inoculation, which is an indicative of greater grain production. This is indicated by significant interactions between PGPR strains and time of harvests for parameters on N uptake and at. % 15Ne of tassel. The phenomenon is also supported by the lower N content in tassels of maize treated with PGPR, namely, B. pumilus S1r1, K. pneumoniae Fr1, B. subtilis UPMB10 and Acinetobacter sp. S3r2 at D65 harvest. This study provides evidence that PGPR inoculation, namely, B. pumilus S1r1 can biologically fix atmospheric N2 and provide an alternative technique, besides plant breeding, to delay N remobilisation in maize plant for higher ear yield (up to 30.9%) with reduced fertiliser-N input.
    Matched MeSH terms: Agriculture/methods
  8. Effect on heavy metals concentration from vermiconversion of agro-waste mixed with landfill leachate
    Azizi AB, Choy MY, Noor ZM, Noorlidah A
    Waste Manag, 2015 Apr;38:431-5.
    PMID: 25670166 DOI: 10.1016/j.wasman.2015.01.020
    Spent Pleurotus sajor-caju compost mixed with livestock excreta, i.e. cow dung or goat manure, was contaminated with landfill leachate and vermiremediated in 75 days. Results showed an extreme decrease of heavy metals, i.e. Cd, Cr and Pb up to 99.81% removal as effect of vermiconversion process employing epigeic earthworms i.e. Lumbricus rubellus. In addition, there were increments of Cu and Zn from 15.01% to 85.63%, which was expected as non-accumulative in L. rubellus and secreted out as contained in vermicompost. This phenomenon is due to dual effects of heavy metal excretion period and mineralisation. Nonetheless, the increments were 50-fold below the limit set by EU and USA compost limits and the Malaysian Recommended Site Screening Levels for Contaminated Land (SSLs). Moreover, the vermicompost C:N ratio range is 20.65-22.93 and it can be an advantageous tool to revitalise insalubrious soil by acting as soil stabiliser or conditioner.
    Matched MeSH terms: Agriculture
  9. Adsorption of 2,4-dichlorophenoxyacetic acid by mesoporous activated carbon prepared from H3PO4-activated langsat empty fruit bunch
    Njoku VO, Islam MA, Asif M, Hameed BH
    J Environ Manage, 2015 May 1;154:138-44.
    PMID: 25721981 DOI: 10.1016/j.jenvman.2015.02.002
    The removal of toxic herbicide from wastewater is challenging due to the availability of suitable adsorbents. The Langsat empty fruit bunch is an agricultural waste and was used in this study as a cheap precursor to produce activated carbon for the adsorption of herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) at different initial concentrations ranging from 50 to 400 mg/L. The produced Langsat empty fruit bunch activated carbon (LEFBAC) was mesoporous and had high surface area of 1065.65 m(2)/g with different active functional groups. The effect of shaking time, temperature and pH on 2,4-D removal were investigated using the batch technique. The adsorption capacity of 2,4-D by LEFBAC was decreased with increase in pH of solution whereas adsorption capacity increased with temperature. The adsorption data was well described by Langmuir isotherm followed by removal capacity of 261.2 mg/g at 30 °C. The results from this work showed that LEFBAC can be used as outstanding material for anionic herbicide uptake from wastewater.
    Matched MeSH terms: Agriculture
  10. Occurrence of veterinary antibiotics and progesterone in broiler manure and agricultural soil in Malaysia
    Ho YB, Zakaria MP, Latif PA, Saari N
    Sci Total Environ, 2014 Aug 1;488-489:261-7.
    PMID: 24836135 DOI: 10.1016/j.scitotenv.2014.04.109
    Repeated applications of animal manure as fertilizer are normal agricultural practices that may release veterinary antibiotics and hormones into the environment from treated animals. Broiler manure samples and their respective manure-amended agricultural soil samples were collected in selected locations in the states of Selangor, Negeri Sembilan and Melaka in Malaysia to identify and quantify veterinary antibiotic and hormone residues in the environment. The samples were analyzed using ultrasonic extraction followed by solid phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The broiler manure samples were found to be contaminated with at least six target analytes, namely, doxycycline, enrofloxacin, flumequine, norfloxacin, trimethoprim and tylosin. These analytes were detected in broiler manure samples with maximum concentrations reaching up to 78,516 μg kg(-1) dry weight (DW) (doxycycline). For manure-amended agricultural soil samples, doxycycline and enrofloxacin residues were detected in every soil sample. The maximum concentration of antibiotic detected in soil was 1331 μg kg(-1) DW (flumequine). The occurrence of antibiotics and hormones in animal manure at high concentration poses a risk of contaminating agricultural soil via fertilization with animal manure. Some physico-chemical parameters such as pH, total organic carbon (TOC) and metal content played a considerable role in the fate of the target veterinary antibiotics and progesterone in the environment. It was suggested that these parameters can affect the adsorption of pharmaceuticals to solid environmental matrices.
    Matched MeSH terms: Agriculture
  11. Persistence of cyfluthrin in three Malaysian agricultural soils under laboratory conditions
    Lee-Yin C, Ismaill BS, Salmijah S, Halimah M
    J Environ Biol, 2013 Sep;34(5):957-61.
    PMID: 24558812
    The influence of temperature, moisture and organic matter on the persistence of cyfluthrin was determined using three types of Malaysian soils, namely clay, clay loam and sandy clay loam obtained from a tomato farm in Cameron Highlands, Pahang. The persistence of cyfluthrin was observed in the laboratory at two temperature levels of 25 and 35 degreeC and field water capacity of 30 and 80%. Treated soil samples were incubated in a growth chamber for 1, 2, 3, 5, 7, 10, 14, 21 and 28 days. The results from the incubation studies showed that temperature and organic matter content significantly reduced the half-life (t1/2) values of cyfluthrin in the three soil types, but moisture content had very little effect. It was observed that cyfluthrin persisted longer at lower temperature and moisture content and higher organic matter content in all the three soil types. The present study demonstrated that under the tropical conditions of Malaysia, cyfluthrin dissipated rapidly in soils compared to its dissipation in soils of temperate regions, evidently due to high temperature.
    Matched MeSH terms: Agriculture
  12. Exploring cancer development in adulthood: cholinesterase depression and genotoxic effect from chronic exposure to organophosphate pesticides among rural farm children
    How V, Hashim Z, Ismail P, Md Said S, Omar D, Bahri Mohd Tamrin S
    J Agromedicine, 2014;19(1):35-43.
    PMID: 24417530 DOI: 10.1080/1059924X.2013.866917
    Children are the vulnerable group in the agricultural community due to their early exposure to pesticides through the dynamic interplay between genetic predisposition, environment, and host-related factors. This study aims to identify the possible association between the depression in blood cholinesterase level and genotoxic effect among farm children. The results of micronuclei assay and comet assay showed that the reduced blood cholinesterase level from organophosphate pesticide exposure is significantly associated with an increase in chromosome breakage and DNA strand breaks. These genotoxicity end points suggest that farm children's cells experience early DNA damage that may lead to uncontrolled cell proliferation during their adulthood. Thus, farm children who grow up near pesticide-treated farmland have a higher probability of developing cancer than children with minimal or zero exposure to pesticides.
    Matched MeSH terms: Agriculture
  13. Loneliness and depression among the elderly in an agricultural settlement: mediating effects of social support
    Wan Mohd Azam WM, Din NC, Ahmad M, Ghazali SE, Ibrahim N, Said Z, et al.
    Asia Pac Psychiatry, 2013 Apr;5 Suppl 1:134-9.
    PMID: 23857850 DOI: 10.1111/appy.12061
    INTRODUCTION: Loneliness has long been known to have strong association with depression. The relationship between loneliness and depression, however, has been associated with other risk factors including social support. The aim of this paper is to describe the role of social support in the association between loneliness and depression.
    METHODS: This cross-sectional study examined the mediating effects of social support among 161 community-based elderly in agricultural settlement of a rural area in Sungai Tengi, Malaysia. Subjects were investigated with De Jong Gierveld Loneliness Scale, Geriatric Depression Scale and Medical Outcome Survey Social Support Survey. Data were analyzed using Pearson correlation, linear and hierarchical regression.
    RESULTS: Results indicated that social support partially mediated the relationship between loneliness and depression.
    DISCUSSION: This suggests that social support affects the linear association between loneliness and depression in the elderly.
    KEYWORDS: depression; elderly; loneliness; rural community; social support
    Study site; FELDA Sungai Tengi, Selangor, Malaysia
    Device, Questionnaire & Scale: De Jong Gierveld Loneliness Scale; Geriatric Depression Scale (GDS-15): Medical Outcome Survey Social Support Survey
    Matched MeSH terms: Agriculture
  14. Fulltext Study of heavy metal levels among farmers of Muda Agricultural Development Authority, Malaysia
    Ghazali AR, Abdul Razak NE, Othman MS, Othman H, Ishak I, Lubis SH, et al.
    J Environ Public Health, 2012;2012:758349.
    PMID: 22536276 DOI: 10.1155/2012/758349
    Heavy metals, particularly cadmium, lead, and arsenic, constitute a significant potential threat to human health. This study was conducted to determine the levels of cadmium, lead, and arsenic in nail samples from farmers at Muda Agricultural Development Authority (MADA), Kedah, Malaysia, and evaluate factors that can contribute to their accumulations. A total of 116 farmers participated in this study. Inductively coupled plasma mass spectrometry (ICP-MS) was used to analyze concentration of heavy metals in the nail samples and questionnaires were given to participants to get demographic, health status, and their agricultural activities data. In this paper, the level of heavy metals was within the normal range and varies according to demographic factors. We found that there were significant correlations between working period with level of lead and arsenic (r=0.315 and r=0.242, resp., P<0.01) and age with lead level (r=0.175, P<0.05). Our findings suggested that agricultural activities could contribute to the accumulation of heavy metals in farmers. Hence, the control of environmental levels of and human exposure to these metals to prevent adverse health effects is still an important public health issue.
    Matched MeSH terms: Agriculture
  15. Fulltext Changes in forest land use and management in Sabah, Malaysian Borneo, 1990-2010, with a focus on the Danum Valley region
    Reynolds G, Payne J, Sinun W, Mosigil G, Walsh RP
    Philos Trans R Soc Lond B Biol Sci, 2011 Nov 27;366(1582):3168-76.
    PMID: 22006960 DOI: 10.1098/rstb.2011.0154
    In an earlier special issue of this journal, Marsh & Greer summarized forest land use in Sabah at that time and gave an introduction to the Danum Valley Conservation Area. Since that assessment, during the period 1990-2010, the forests of Sabah and particularly those of the ca 10 000 km(2) concession managed on behalf of the State by Yayasan Sabah (the Sabah Foundation) have been subject to continual, industrial harvesting, including the premature re-logging of extensive tracts of previously only once-logged forest and large-scale conversion of natural forests to agricultural plantations. Over the same period, however, significant areas of previously unprotected pristine forest have been formally gazetted as conservation areas, while much of the forest to the north, the south and the east of the Danum Valley Conservation Area (the Ulu Segama and Malua Forest Reserves) has been given added protection and new forest restoration initiatives have been launched. This paper analyses these forest-management and land-use changes in Sabah during the period 1990-2010, with a focus on the Yayasan Sabah Forest Management Area. Important new conservation and forest restoration and rehabilitation initiatives within its borders are given particular emphasis.
    Matched MeSH terms: Agriculture
  16. Fulltext Establishing the evidence base for maintaining biodiversity and ecosystem function in the oil palm landscapes of South East Asia
    Foster WA, Snaddon JL, Turner EC, Fayle TM, Cockerill TD, Ellwood MD, et al.
    Philos Trans R Soc Lond B Biol Sci, 2011 Nov 27;366(1582):3277-91.
    PMID: 22006968 DOI: 10.1098/rstb.2011.0041
    The conversion of natural forest to oil palm plantation is a major current threat to the conservation of biodiversity in South East Asia. Most animal taxa decrease in both species richness and abundance on conversion of forest to oil palm, and there is usually a severe loss of forest species. The extent of loss varies significantly across both different taxa and different microhabitats within the oil palm habitat. The principal driver of this loss in diversity is probably the biological and physical simplification of the habitat, but there is little direct evidence for this. The conservation of forest species requires the preservation of large reserves of intact forest, but we must not lose sight of the importance of conserving biodiversity and ecosystem processes within the oil palm habitat itself. We urgently need to carry out research that will establish whether maintaining diversity supports economically and ecologically important processes. There is some evidence that both landscape and local complexity can have positive impacts on biodiversity in the oil palm habitat. By intelligent manipulation of habitat complexity, it could be possible to enhance not only the number of species that can live in oil palm plantations but also their contribution to the healthy functioning of this exceptionally important and widespread landscape.
    Matched MeSH terms: Agriculture
  17. Development of probiotic carriers using microbial transglutaminase-crosslinked soy protein isolate incorporated with agrowastes
    Lew LC, Bhat R, Easa AM, Liong MT
    J Sci Food Agric, 2011 Jun;91(8):1406-15.
    PMID: 21384373 DOI: 10.1002/jsfa.4325
    Probiotics are live micro-organisms that exert beneficial effects on their host. A high survival rate during gastrointestinal transit and storage is often desirable. The main aim of this study was to develop protective carriers for probiotics via the use of enzymatically crosslinked soy protein isolate incorporated with agrowastes such as banana peel, banana pulp, cempedak rind and cocoa rind.
    Matched MeSH terms: Agriculture
  18. Fulltext Accumulation of soil carbon and phosphorus contents of a rehabilitated forest
    Haruna Ahmed O, Aainaa Hasbullah N, Ab Majid NM
    ScientificWorldJournal, 2010 Oct 12;10:1988-95.
    PMID: 20953548 DOI: 10.1100/tsw.2010.196
    The world's tropical rainforests are decreasing at an alarming rate as they are converted to agricultural land, pasture, and plantations. Decreasing tropical forests affect global warming. As a result, afforestation progams have been suggested to mitigate this problem. The objective of this study was to determine the carbon and phosphorus accumulation of a rehabilitated forest of different ages. The size of the study area was 47.5 ha. Soil samples were collected from the 0-, 6-, 12-, and 17-year-old rehabilitated forest. Twenty samples were taken randomly with a soil auger at depths of 0-20 and 20-40 cm. The procedures outlined in the Materials and Methods section were used to analyze the soil samples for pH, total C, organic matter, total P, C/P ratio, yield of humic acid (HA), and cation exchange capacity (CEC). The soil pH decreased significantly with increasing age of forest rehabilitation regardless of depth. Age did not affect CEC of the rehabilitated forest. Soil organic matter (SOM), total C, and total P contents increased with age. However, C/P ratio decreased with time at 0-20 cm. Accumulation of HA with time and soil depth was not consistent. The rehabilitated forest has shown signs of being a C and P sink.
    Matched MeSH terms: Agriculture
  19. Sorption kinetics and isotherm studies of a cationic dye using agricultural waste: broad bean peels
    Hameed BH, El-Khaiary MI
    J Hazard Mater, 2008 Jun 15;154(1-3):639-48.
    PMID: 18063301
    In this paper, broad bean peels (BBP), an agricultural waste, was evaluated for its ability to remove cationic dye (methylene blue) from aqueous solutions. Batch mode experiments were conducted at 30 degrees C. Equilibrium sorption isotherms and kinetics were investigated. The kinetic data obtained at different concentrations have been analyzed using pseudo-first-order, pseudo-second-order and intraparticle diffusion equations. The experimental data fitted very well the pseudo-first-order kinetic model. Analysis of the temportal change of q indicates that at the beginning of the process the overall rate of adsorption is controlled by film-diffusion, then at later stage intraparticle-diffusion controls the rate. Diffusion coefficients and times of transition from film to pore-diffusion control were estimated by piecewise linear regression. The experimental data were analyzed by the Langmuir and Freundlich models. The sorption isotherm data fitted well to Langmuir isotherm and the monolayer adsorption capacity was found to be 192.7 mg/g and the equilibrium adsorption constant Ka is 0.07145 l/mg at 30 degrees C. The results revealed that BBP was a promising sorbent for the removal of methylene blue from aqueous solutions.
    Matched MeSH terms: Agriculture
  20. Equilibrium and kinetic studies of methyl violet sorption by agricultural waste
    Hameed BH
    J Hazard Mater, 2008 Jun 15;154(1-3):204-12.
    PMID: 18023971
    In this work, sunflower (Helianthus annuus L.) seed hull (SSH), an agricultural waste, was evaluated for its ability to remove methyl violet (MV) from aqueous solutions. Sorption isotherm of MV onto the SSH was determined at 30 degrees C with the initial concentrations of MV in the range of 25-300 mg/L. The equilibrium data were analyzed using the Langmuir, Freundlich and Temkin isotherm models. The equilibrium process was described well by the Freundlich isotherm model. The maximum SSH sorption capacity was found to be 92.59 mg/L at 30 degrees C. The kinetic data were studied in terms of the pseudo-first-order, pseudo-second-order and intraparticle diffusion kinetic models. The pseudo-second-order model best described the sorption process. A single-stage batch-adsorber design of the adsorption of MV onto SSH was studied based on the Freundlich isotherm equation. The results indicated that sunflower seed hull was an attractive candidate for removing methyl violet from aqueous solution.
    Matched MeSH terms: Agriculture
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