• Title/Summary/Keyword: tropical soils

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A Study on Features of Forage Barnyard Millet and Related Research Trends

  • Lim, Eun-A;Lee, Ki-Won;Choi, Bo Ram;Park, Hyung Soo;Woo, Jae Hoon;Kim, Da In;Lee, Sang-Hoon
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.41 no.3
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    • pp.217-222
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    • 2021
  • Barnyard millet is a short-lived tropical, short-term C4 plant and has superior vitality in humid conditions owing to its freshwater habitat. It shows strong adaptability to soils with poor drainage and low fertility, and efficiently competes with rice in paddy fields. Barnyard millet grain is used as feed in the Indian region and is a great source of dietary fiber, proteins, fats, vitamins, and some essential amino acids. Considering its high nutritional value and its potential as a food resource and fodder crop, various countries are showing interest in cultivating barnyard millet. However, in Korea, farm households have not yet recognized the benefits of cultivating barnyard millet, and research regarding this is scarce. In this review, the features of forage barnyard millet and its related research trends are discussed, with the aim of improving interest in this crop and promoting its cultivation.

Estimation of radiostrontium, radiocesium and radiobarium transfer from arid soil to plant: A case study from Kuwait

  • Aba, Abdulaziz;Ismaeel, Anfal;Al-Boloushi, Omar
    • Nuclear Engineering and Technology
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    • v.53 no.3
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    • pp.960-966
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    • 2021
  • A technical approach to design and carry out an experiment to determine the uptake of selected radionuclides in site-specific conditions in Kuwait was developed and successfully executed for developing a radioecological decision support system. The radionuclides from soil-to-plant transfer factors have been obtained for leafy and non-leafy vegetables, and root crops cultivated in Kuwait. Two types of vegetated soils were selected and spiked with high concentrations of three relatively short-lived selected radionuclides (85Sr, 134Cs, and 133Ba). The highest strontium and barium transfer factors were found in the order: leafy vegetables > root crops > non-leafy vegetables. The approximate range of radiocesium transfer factor was found to be low in all plant groups and was comparable to those reported elsewhere in different soil types of temperate and tropical environments. A strong negative correlation between the obtained transfer factors and the distribution coefficient of the radionuclide in soil was found. It is recommended to adopt the newly derived parameters for the sensitive areas in Kuwait and other Gulf countries instead of using the generic parameters, whenever dose calculation codes are used. This will help to more accurately assess and predict the end results of the committed effective dose equivalent through ingestion pathway.

Development of Seashore Paspalum Turfgrass with Herbicide Resistance

  • Kim, Kyung-Moon;Song, In-Ja;Lee, Hyo-Yeon;Raymer, Paul;Kim, Beom-Seok;Kim, Wook
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.54 no.4
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    • pp.427-432
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    • 2009
  • Seashore Paspalum (Paspalum vaginatum Swartz) is a warm season grass and indigenous to tropical and subtropical regions of coastal areas worldwide. The species is used as feed for cattle and horses and has been very successful for golf courses worldwide. One of the most outstanding characteristics of seashore paspalum is its tolerance to saline soils compared to other warm season turfgrasses. The development of new seashore paspalum cultivars with improved traits could be facilitated through the application of biotechnological strategies. The purpose of this study was to product for herbicide resistant seashore paspalum using Arobacterium-mediated transformation and this study is the first report on transformation and herbicideresistant transgenic plants in seashore paspalum. Embryogenic calli were induced from the seeded variety of pseashore paspalum. Embryogenic calli were transformed with Agrobacterium tumefaciens strain EHA105 carrying the binary vector pCAMBIA3301 with two genes encoding gusA and bar. Transformed calli and plants were selected on medium containing 3 mg/l PPT. PCR detected the presence of the gusA and bar gene, indicating both genes are integrated into the genome of seashore paspalum. A chlorophenol red assay was used to confirm that the bar gene was expressed. By application of herbicide BASTA, the herbicide resistance in the transgenic seashore paspalum plants was confirmed.

Reports of Drawida (Oligochaeta: Moniligastridae) from far East Asia

  • Blakemore, Robert J.;Lee, Seunghan;Seo, Hong-Yul
    • Journal of Species Research
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    • v.3 no.2
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    • pp.127-166
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    • 2014
  • Moniligastrids are an important yet often ignored earthworm group commonly found in cultivated soils, especially paddy, in the tropical East. Seven new taxa are: Drawida koreana austri, D. koreana nanjiro, D. koreana shindo, D. odaesan, D. jeombongsan, D. companio and D. csuzdii Blakemore spp. or sub-spp. nov. from Korea. Drawida csuzdii is the first new species from North Korea since Lumbricidae Eisenia koreana (Zicsi, 1972). Historical East Asian moniligastrids are reviewed chronologically and Drawida barwelli (Beddard, 1886), D. japonica (Michaelsen, 1892) and D. siemsseni Michaelsen, 1910 are compared on their museum types. These three taxa were thought similar and related to D. nepalensis Michaelsen, 1907 and its possible synonym D. burchardi Michaelsen, 1903 (priority!) and both of these to prior D. uniqua (Bourne, 1887). Indian Drawida calebi Gates, 1945 is compared to new material of D. japonica from Japan, and D. willsi Michaelsen, 1907 to the new sub-species of D. koreana Kobayashi, 1938 from Korea. Where available, mtDNA COI gene barcodes are provided to help objective determinations and a phylogram is provided with outgroup Ocnerodrilidae Eukerria saltensis (Beddard, 1895) itself found in rice paddy/irrigation. The challenge now is comparison of all early taxa in their various homelands in order to assess the genetic variability and taxonomic boundaries acceptable, especially for unpigmented D. barwelli and also for pink/grey D. japonica and blue/grey D. koreana. A checklist of moniligastrids is appended showing 22 species from China (including Hainan and Taiwan), 21 from Korea, nine from Japan and the Drawida ghilarovi Gates, 1969 species-complex from far eastern Russian (Siberia). Recent Drawida dandongensis Zhang & Sun, 2014 from Sino-Korean border is misdescribed and cannot be meaningfully compared to any other Drawidas.

Fuel Management and Experimental Wildfire Effects on Forest Structure, Tree Mortality and Soil Chemistry in Tropical Dry Forests in Ghana

  • Barnes, Victor R;Swaine, Mike D;Pinard, Michelle A;Kyereh, Boateng
    • Journal of Forest and Environmental Science
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    • v.33 no.3
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    • pp.172-186
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    • 2017
  • The effects of application of fuel-reduction treatment in wildfire management has not been tested in dry forests of Ghana. Therefore, the short-term ecological effects of prescribed burning and hand thinning treatments followed by experimental wildfire were investigated in degraded forests and Tectona grandis forest plantations in two forest reserves of different levels of dryness in Ghana. The results showed that more trees were killed in prescribed burning (average of 41% in degraded forest and 18% in plantations) than hand thinning (7.2% in degraded forests and 8% in plantation). More tree seedlings were also killed in prescribed burning (72%) than hand thinning (47%). The mortality of trees and seedlings were greater in Worobong South forest, a less dry forest reserve than the Afram Headwaters forest, a drier forest reserve. Fuel treatment especially prescribed burning compared to the control reduced wildfire effects on forest canopy particularly in the less dry forest and tree mortality especially in the drier forest. Prescribed burning temporarily increased pH, exchangeable potassium (52%) and available phosphorus (82%) in the surface soils of the entire plots. The two fuel treatment methods did not have much influence on basal area, organic matter and total nitrogen. Nevertheless, they were able to reduce the adverse wildfire effects on soil pH, exchangeable potassium, available phosphorus, organic matter and total nitrogen concentrations. Fuel treatments therefore have potential application in dry forest management in Ghana due to their ability to retain important forest ecological traits after a wildfire incidence.

Environmental Factors Influencing Tree Species Regeneration in Different Forest Stands Growing on a Limestone Hill in Phrae Province, Northern Thailand

  • Asanok, Lamthai;Marod, Dokrak
    • Journal of Forest and Environmental Science
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    • v.32 no.3
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    • pp.237-252
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    • 2016
  • Improved knowledge of the environmental factors affecting the natural regeneration of tree species in limestone forest is urgently required for species conservation. We examined the environmental factors and tree species characteristics that are important for colonization in diverse forest stands growing on a limestone hill in northern Thailand. Our analysis estimated the relative influence of forest structure and environmental factors on the regeneration traits of tree species. We established sixty-four $100-m^2$ plots in four forest stands on the limestone hill. We determined the species composition of canopy trees, regenerating seedlings, and saplings in relation to the physical environment. The relationships between environmental variables and tree species abundance were assessed by canonical correspondence analysis (CCA), and we used generalized linear mixed models to examine data on seedling/sapling abundances. The CCA ordination indicated that the abundance of tree species within the mixed deciduous forest was closely related to soil depth. The abundances of tree species growing within the sink-hole and hill-slope stands were positively related to the extent of rocky outcropping; light and soil moisture positively influenced the abundance of tree species in the hill-cliff stand. Physical factors had a greater effect on tree regeneration than did factors related to forest structure. Tree species, such as Ficus macleilandii, Dracaena cochinchinensis, and Phyllanthus mirabilis within the hill-cliff or sink-hole stand, colonized well on large rocky outcroppings that were well illuminated and had soft soils. These species regenerated well under conditions prevailing on the limestone hill. The colonization of several species in other stands was negatively influenced by environmental conditions at these sites. We found that natural regeneration of tree species on the limestone hill was difficult because of the prevailing combination of physical and biological factors. The influence of these factors was species dependent, and the magnitude of effects varied across forest stands.

Estimation of High-Resolution Soil Moisture Using Sentinel-1A/B SAR and Soil Moisture Data Assimilation Scheme (Sentinel-1A/B SAR와 토양수분자료동화기법을 이용한 고해상도 토양수분 산정)

  • Kim, Sangwoo;Lee, Taehwa;Chun, Beomseok;Jung, Younghun;Jang, Won Seok;Sur, Chanyang;Shin, Yongchul
    • Journal of The Korean Society of Agricultural Engineers
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    • v.62 no.6
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    • pp.11-20
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    • 2020
  • We estimated the spatio-temporally distributed soil moisture using Sentinel-1A/B SAR (Synthetic Aperture Radar) sensor images and soil moisture data assimilation technique in South Korea. Soil moisture data assimilation technique can extract the hydraulic parameters of soils using observed soil moisture and GA (Genetic Algorithm). The SWAP (Soil Water Atmosphere Plant) model associated with a soil moisture assimilation technique simulates the soil moisture using the soil hydraulic parameters and meteorological data as input data. The soil moisture based on Sentinel-1A/B was validated and evaluated using the pearson correlation and RMSE (Root Mean Square Error) analysis between estimated soil moisture and TDR soil moisture. The soil moisture data assimilation technique derived the soil hydraulic parameters using Sentinel-1A/B based soil moisture images, ASOS (Automated Synoptic Observing System) weather data and TRMM (Tropical Rainfall Measuring Mission)/GPM (Global Precipitation Measurement) rainfall data. The derived soil hydrological parameters as the input data to SWAP were used to simulate the daily soil moisture values at the spatial domain from 2001 to 2018 using the TRMM/GPM satellite rainfall data. Overall, the simulated soil moisture estimates matched well with the TDR measurements and Sentinel-1A/B based soil moisture under various land surface conditions (bare soil, crop, forest, and urban).

Influences of Termite Activities on Ecosystem Carbon Cycle: Focusing on Coarse Woody Debris Decomposition (흰개미가 생태계 탄소 순환에 미치는 영향: 고사목 분해를 중심으로)

  • Kim, Seongjun;Lee, Jongyeol;Han, Seung Hyun;Chang, Hanna;Lee, Sohye;Yun, Hyeon Min;Son, Yowhan
    • Journal of Korean Society of Forest Science
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    • v.105 no.1
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    • pp.1-11
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    • 2016
  • Globally, there are more than 2600 species of termites which adapted plenty of terrestrial ecosystems by various strategies such as making termite nest and society. Various studies were recently carried out on termites because they play significant roles in the context of carbon (C) cycle of terrestrial ecosystems. According to the results of previous studies, termite activities influenced the amount of soil organic C, methane emission, and organic matter decomposition. Termite nests, where termite biomass was concentrated, exhibited 1.8 times higher soil organic C concentration than reference soils, and emitted $0.0-6.0kg\;ha^{-1}year^{-1}$ of methane in tropical forests and savannas. Feeding activity of termites, in addition, accelerated coarse woody debris (CWD) decomposition by increasing the surface area to volume ratio of CWD. Especially, CWD decomposition induced by the Rhinotermitidae family appeared to be significant for the C cycle in temperate forests. However, more studies should be conducted on termite-induced CWD decomposition in temperate forests because few studies have dealt with it. The termite-induced CWD decomposition could be measured by preparing disc-shaped CWD samples, excluding access of termites to the CWD samples, and comparing the decomposition rate of the CWD samples with and without the termite exclusion treatment. Studies on the termite-induced CWD decomposition would contribute to further elucidation of the C cycle in temperate forests.

Carbon stocks and factors affecting their storage in dry Afromontane forests of Awi Zone, northwestern Ethiopia

  • Gebeyehu, Getaneh;Soromessa, Teshome;Bekele, Tesfaye;Teketay, Demel
    • Journal of Ecology and Environment
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    • v.43 no.1
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    • pp.43-60
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    • 2019
  • Background: Tropical montane forests played an important role in the provision of ecosystem services. The intense degradation and deforestation for the need of agricultural land expansion result in a significant decline of forest cover. However, the expansion of agricultural land did not completely destruct natural forests. There remain forests inaccessible for agricultural and grazing purpose. Studies on these forests remained scant, motivating to investigate biomass and soil carbon stocks. Data of biomass and soils were collected in 80 quadrats ($400m^2$) systematically in 5 forests. Biomass and disturbance gradients were determined using allometric equation and disturbance index, respectively. The regression modeling is employed to explore the spatial distribution of carbon stock along disturbance and environmental gradients. Correlation analysis is also employed to identify the relation between site factors and carbon stocks. Results: The result revealed that a total of 1655 individuals with a diameter of ${\geq}5cm$, representing 38 species, were measured in 5 forests. The mean aboveground biomass carbon stocks (AGB CS) and soil organic carbon (SOC) stocks at 5 forests were $191.6{\pm}19.7$ and $149.32{\pm}6.8Mg\;C\;ha^{-1}$, respectively. The AGB CS exhibited significant (P < 0.05) positive correlation with SOC and total nitrogen (TN) stocks, reflecting that biomass seems to be a general predictor of SOCs. AGB CS between highly and least-disturbed forests was significantly different (P < 0.05). This disturbance level equates to a decrease in AGB CS of 36.8% in the highly disturbed compared with the least-disturbed forest. In all forests, dominant species sequestrated more than 58% of carbon. The AGB CS in response to elevation and disturbance index and SOC stocks in response to soil pH attained unimodal pattern. The stand structures, such as canopy cover and basal area, had significant positive relation with AGB CS. Conclusions: Study results confirmed that carbon stocks of studied forests were comparable to carbon stocks of protected forests. The biotic, edaphic, topographic, and disturbance factors played a significant variation in carbon stocks of forests. Further study should be conducted to quantify carbon stocks of herbaceous, litter, and soil microbes to account the role of the whole forest ecosystem.

Fertility and Rate of Fertilizer Application for Orchard Soils of Apple and Pear (사과 및 배 과수토양(果樹土壤)의 비옥도구분(肥沃度區分)에 의한 시비기준(施肥基準) 설정(設定))

  • Lee, Choon-Soo;Lee, Ju-Young;Lee, Yong-Jae;Shin, Jae-Sung;Han, Ki-Hak;Kim, Dong-Soo
    • Korean Journal of Soil Science and Fertilizer
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    • v.26 no.2
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    • pp.103-110
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    • 1993
  • This study was made to evaluate the chemical properties of 481 farmers' orchard fields in An-Seong area. And the reasonable ferilizer rates were recommended utilizing the result of soil analysis. The results are summarized as follows : 1. As the soil fertility status of collected soil samples were evaluated on the basis of temporary optimal range for each soil chemical properties, 12.7 to 49.6% of the total 481 farmers' fields were range for soil improvement. 2. The contents of chemical component have a tendancy to decrease with depth gradually from surface to subsoil. 3. According to the relationship between the contents of soil component in subsoil and those in surface soil, the fertility condition of subsoil could be estimated on the basis of analysis data of surface soil. 4. The multiple regression equation for pear yield prediction to the organic matter and exchangable calcium contents in the soil were obtained. 5. Referring the average value, distribution ratio compared to the optimum level for each soil chemical properties and standard fertilizer rate, the soil fertility status could be categorized as "High" "Medium" and "Low". For each category, the recommended amounts for NPK and organic matter application were established. 6. The recommended rates through soul fertility diagnosis were less than farmer's dosage in the range 7.1~7.7 kg/10a for N, 0.8~11.5 kg/10a for $P_2O_5$, 7.1~19.9 kg/10a for $K_2O$ and 90~116 kg/10a for lime.

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