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Soil Physico-Chemical Properties and Different Altitudes Affect Arbuscular Mycorrhizal Fungi Abundance and Colonization in Cacao Plantations of Cameroon
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作者 Franklin Tounkam Ketchiemo Beaulys Fotso +4 位作者 Astride Stéphanie Mouafi Djabou Victor Jos Eyamo Evina Japhet Youri Essambita Franck Maxime Ewane Tang Nicolas Niemenak 《American Journal of Plant Sciences》 CAS 2024年第2期57-82,共26页
This study aims to investigate the abundance of AMF according to soil properties and altitudes in different cacao plantations of Cameroon. Physico-chemical analyses were made on soil samples collected from three agro-... This study aims to investigate the abundance of AMF according to soil properties and altitudes in different cacao plantations of Cameroon. Physico-chemical analyses were made on soil samples collected from three agro-ecological zones. Soil samples were also used to evaluate directly the AMF abundance following the various altitudes and after trapping by sorghum plant. The results showed that soil properties, AMF spore abundances and colonization fluctuated significantly at different altitudes. The most represented texture was sandy loam. The bimodal zone presented a homogeneous texture (sandy loam) in all its localities. Cacao soil chemical characteristics showed that, the highest nitrogen rate (0.47%;p 0.05, Scott-Knott test) was recorded at Melong in a monomodal zone while Tonga in the Western highlands displayed the lowest rate (0.13%). Soil P concentration was significantly high in monomodal zones (Mbanga and Melong). Soil pH level indicated that the soil from Tonga in the Western highlands was neutral (pH = 6.67), and soils of other localities under study were acidic with the lowest (4.75) pH level recorded at Melong in a monomodal zone. In soil samples, the highest spore density (1.03 spores/g soil) was observed at Ntui in Bimodal zone, while the lowest spore density (0.26 spores/g soil) was observed at Bafang in the Western highlands. Root colonization showed that the sample from Bokito in a bimodal zone displayed the best frequency of mycorrhization (86.11%) while the sample from Bafang in the Western highlands recorded the lowest (27.11%). The PCA analysis highlighted that available phosphorus, pH and altitude all strongly correlated with AMF root colonization ability and can be used as a predictor of AMF colonization ability in cacao rhizosphere. 展开更多
关键词 Agroecological Zone Altitude Variations Arbuscular Mycorrhizal Fungi soil Properties Theobroma cacao
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Physico-Chemical and Nutritional Properties of a Food Broth Based on Nere (Parkia biglobosa)
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作者 Lassana Bamba Gervais Melaine M’Boh +5 位作者 N’Gbésso Amos Ekissi Kipré Laurent Séri Gnogbo Alexis Bahi Koffi Pierre Valery Niaba Allico Joseph Djaman Grah Avit Maxwell Beugre 《Food and Nutrition Sciences》 CAS 2024年第5期377-389,共13页
Purpose: Diet and eating habits are major risk factors for the health and the development of disease, such as, for example, metabolic disorder leading to cardiovascular pathology and cancer, decreased immunity exposin... Purpose: Diet and eating habits are major risk factors for the health and the development of disease, such as, for example, metabolic disorder leading to cardiovascular pathology and cancer, decreased immunity exposing to infections. This study of the physico-chemical and nutritional properties of a soumara-based food broth was carried out with the aim of promoting the consumption of organic broth made from nere seeds (soumara). That is to alleviate certain metabolic diseases, which is a matter of food safety, and also to limit the risk for the health about the consumption of some cooking stocks on the market. Methods: Several natural ingredients such as nere seeds (soumara), ginger, black pepper, parsley and garlic were used to create a nere-based stock. All these ingredients were freeze-dried and the powder obtained was used to make the broth, regarding their physical and chemical properties. Results: The broth had a good protein content of 17.41 ± 0.367 g/100g, a lipid content of 16.80 ± 0.08 g/100g and a fiber content of 8.66 ± 0.04 g/100g. In terms of nutritional values, the broth showed good levels of calcium 184.21 ± 0.09 mg/100g, potassium 50.04 ± 1.45 mg/100g and iron and zinc. In terms of antioxidant activity, the broth also showed good antioxidant activity. Conclusion: Regarding the properties of our food broth, whose composition is based on natural ingredients, could be recommended for consumption and, its properties, could play an important role in preventing and combating certain metabolic diseases. 展开更多
关键词 Food Broth Nere physico-chemical Properties NUTRITION Food Safety
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Experimental investigation into the salinity effect on the physicomechanical properties of carbonate saline soil
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作者 Jiejie Shen Qing Wang +3 位作者 Yating Chen Xuefei Zhang Yan Han Yaowu Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1883-1895,共13页
For engineering structures with saline soil as a filling material,such as channel slope,road subgrade,etc.,the rich soluble salt in the soil is an important potential factor affecting their safety performance.This stu... For engineering structures with saline soil as a filling material,such as channel slope,road subgrade,etc.,the rich soluble salt in the soil is an important potential factor affecting their safety performance.This study examines the Atterberg limits,shear strength,and compressibility of carbonate saline soil samples with different NaHCO3 contents in Northeast China.The mechanism underlying the influence of salt content on soil macroscopic properties was investigated based on a volumetric flask test,a mercury intrusion porosimetry(MIP)test,and a scanning electron microscopic(SEM)test.The results demonstrated that when NaHCO3 contents were lower than the threshold value of 1.5%,the bound water film adsorbed on the surface of clay particles thickened continuously,and correspondingly,the Atterberg limits and plasticity index increased rapidly as the increase of sodium ion content.Meanwhile,the bonding force between particles was weakened,the dispersion of large aggregates was enhanced,and the soil structure became looser.Macroscopically,the compressibility increased and the shear strength(mainly cohesion)decreased by 28.64%.However,when the NaHCO3 content exceeded the threshold value of 1.5%,the salt gradually approached solubility and filled the pores between particles in the form of crystals,resulting in a decrease in soil porosity.The cementation effect generated by salt crystals increased the bonding force between soil particles,leading to a decrease in plasticity index and an improvement in soil mechanical properties.Moreover,this work provides valuable suggestions and theoretical guidance for the scientific utilization of carbonate saline soil in backfill engineering projects. 展开更多
关键词 Carbonate saline soil Salt content Physicomechanical properties Bound water MICROSTRUCTURE
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Effects of site preparation methods on soil physical properties and outplanting success of coniferous seedlings in boreal forests
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作者 Aleksey S.Ilintsev Elena N.Nakvasina Alexander P.Bogdanov 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期70-80,共11页
This study assessed the effect of patch scarification and mounding on the physical properties of the root layer and the success of tree planting in various types of forests.This study was conducted on 12 forest sites ... This study assessed the effect of patch scarification and mounding on the physical properties of the root layer and the success of tree planting in various types of forests.This study was conducted on 12 forest sites in taiga forests of the European part of Russia.A total of 54 plots were set up to assess seedling survival;root collar diameter,height,and heigh increment were measured for 240 seedlings to assess growth.In the rooting layer,240 soil samples were taken to determine physical properties.The study showed that soil treatment methods had no effect on bulk density and total porosity in Cladina sites.However,reduced soil moisture was noted,particularly in mounds,resulting in increased aeration.In Myrtillus sites,there were increased bulk density,reduced soil moisture,and total porosity in the mounds.Mounding treatment in Polytrichum sites resulted in reduced soil moisture and increased aeration porosity.In the Myrtillus and Polytrichum sites,patch scarification had no effects on physical properties.In Polytrichum sites,survival rates,heights,and heigh increments of bareroot Norway spruce seedlings in mounds were higher than in patches;however,the same did not apply to diameter.In Cladina and Myrtillus sites,there was no difference in growth for bareroot and containerised seedlings with different soil treatments.Growing conditions and soil types should be considered when applying different soil treatment methods to ensure high survival rates and successful seedling growth. 展开更多
关键词 Boreal forests Mechanical site preparation Patch scarification MOUNDING soil properties Containerised seedlings Bareroot seedlings
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Physical and mechanical properties and microstructures of submarine soils in the Yellow Sea
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作者 Zhuangcai Tian Yihua Chang +6 位作者 Sichao Chen Gengchen Wang Yanhong Hu Chuan Guo Lei Jia Lei Song Jianhua Yue 《Deep Underground Science and Engineering》 2024年第2期197-206,共10页
In recent years,the exploration of seabed has been intensified,but the submarine soils of silt and sand in the Yellow Sea area have not been well investigated so far.In this study,the physical and mechanical propertie... In recent years,the exploration of seabed has been intensified,but the submarine soils of silt and sand in the Yellow Sea area have not been well investigated so far.In this study,the physical and mechanical properties of silt and sand from the Yellow Sea were measured using a direct shear apparatus and their microstructures were observed using a scanning electron microscope.The test results suggest that the shear strength of silt and sand increases linearly with the increase of normal stress.Based on the direct shear test,the scanning electron microscope was used to observe the section surface of sand.It is observed that the section surface becomes rough,with many“V”‐shaped cracks.Many particles appear on the surface of the silt structure and tend to be disintegrated.The X‐ray diffraction experiment reveals that the sand and silt have different compositions.The shear strength of sand is slightly greater than that of silt under high stress,which is related to the shape of soil particles and the mineral composition.These results can be a reference for further study of other soils in the Yellow Sea;meanwhile,they can serve as soil parameters for the stability and durability analyses of offshore infrastructure construction. 展开更多
关键词 direct shear test MICROSCOPE physical properties submarine soil Yellow Sea
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Impact of Different Rates of Nitrogen Supplementation on Soil PhysicochemicalProperties and Microbial Diversity in Goji Berry
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作者 Xiaojie Liang Wei An +4 位作者 Yuekun Li Yajun Wang Xiaoya Qin Yanhong Cui Shuchai Su 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第3期467-486,共20页
Goji berry(Lycium barbarum L.)is substantially dependent on nitrogen fertilizer application,which can signifi-cantly enhance fruit yield and Goji berry industrial development in Ningxia,China.This study aimed to analyz... Goji berry(Lycium barbarum L.)is substantially dependent on nitrogen fertilizer application,which can signifi-cantly enhance fruit yield and Goji berry industrial development in Ningxia,China.This study aimed to analyze the functions of differential nitrogen application rates including low(N1),medium(N2),and high(N3)levels in soil microbial community structure(bacterial and fungal)at 2 diverse soil depths(0-20,20-40 cm)through high-throughput sequencing technology by targeting 16S RNA gene and ITS1&ITS2 regions.All the observed physicochemical parameters exhibited significant improvement(p<0.05)with increased levels of nitrogen and the highest values for most parameters were observed at N2.However,pH decreased(p<0.05)gradually.The alpha and beta diversity analyses for bacterial and fungal communities’metagenome displayed more similarities than differences among all groups.The top bacterial and fungal phyla and genera suggested no obvious(p>0.05)differences among three group treatments(N1,N2,and N3).Furthermore,the functional enrichment analysis demonstrated significant(p<0.05)enrichment of quorum sensing,cysteine and methionine metabolism,and transcriptional machinery for bacterial communities,while various saprotrophic functional roles for fungal communities.Conclusively,moderately reducing the use of N-supplemented fertilizers is conducive to increasing soil nitrogen utilization rate,which can contribute to sustainable agriculture practices through improved soil quality,and microbial community structure and functions. 展开更多
关键词 Goji berry production Ningxia China differential nitrogen supplementation rates 16S RNA gene and IT1&IT2 region sequencing soil physicochemical properties
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Soil Physico-Chemical Properties and Microflora as Influenced by Bispyribac Sodium 10% SC in Transplanted Kharif Rice 被引量:4
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作者 S.BERA R.K.GHOSH 《Rice science》 SCIE 2013年第4期298-302,共5页
The effects of bispyribac sodium 10% SC and butachlor 50% SC on soil physico-chemical properties and microflora in transplanted kharifrice were investigated over two seasons (2010 and 2011 ) Effects of the herbicide... The effects of bispyribac sodium 10% SC and butachlor 50% SC on soil physico-chemical properties and microflora in transplanted kharifrice were investigated over two seasons (2010 and 2011 ) Effects of the herbicide on bulk density, water holding capacity, moisture content, soil pH, organic matter content, electrical conductivity, as well as total nitrogen, available phosphorus and available potassium contents were analyzed along with microflora population (total bacteria, actinomycetes and fungi). No significant changes in soil physico-chemical properties were observed. Herbicide treatments resulted in decreases in microbial counts initially. With the degradation of applied herbicides within a considerable time, the microflora populations even exceeded the initial count at 60 d after application of the herbicide. 展开更多
关键词 HERBICIDE bispyribac sodium physico-chemical property soil microflora population RICE
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Comparison of soil physico-chemical properties under different land-use and cover types in northeastern China's Horqin Sandy Land 被引量:4
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作者 YuQiang Li JianPeng Zhang +4 位作者 XueYong Zhao TongHui Zhang YuLin Li XinPing Liu YinPing Chen 《Research in Cold and Arid Regions》 CSCD 2016年第6期495-506,共12页
The Horqin Sandy Land of northeastern China was originally a grassland with plenty of water and lush vegetation dominated by palatable grass species along with sparsely scattered woody species. However, it has experie... The Horqin Sandy Land of northeastern China was originally a grassland with plenty of water and lush vegetation dominated by palatable grass species along with sparsely scattered woody species. However, it has experienced severe desertification in recent decades due to its fragile ecology together with inappropriate human activities. Currently, the landscape of the Horqin Sandy Land is dominated by irrigated croplands and sand dunes with different degrees of vegetation cover, as the region has become the most important part of the semiarid agro-pastoral ecotone of northern China. In this study, we compared soil physical and chemical properties under different land-use and cover types (irrigated cropland, rainfed cropland, sandy grassland, fixed dunes, and mobile dunes). We found that soil particle size distribution; organic C, total N, and total mineral element, microelement, and available microelement and nutrient contents; pH; CEC; and bulk density differed significantly among the land-use and cover types. In general, soil quality was highest in the cropland, intermediate in the sandy grassland, and lowest in the dunes. The most important soil quality attribute, soil organic carbon (SOC) storage, decreased in the fol-lowing order: irrigated cropland (5,699 g/m^2) 〉 sandy grassland (3,390 g/m^2) 〉 rainfed cropland (2,411 g/m^2) 〉 fixed dunes (821 g/m^2) 〉 mobile dunes (463 g/m^2). SOC was significantly positively correlated with a large proportion of the other soil physico-chemical parameters. Our results suggest that the key issue in restoration of the degraded soils will be to increase SOC storage, which would also create a high potential for sequestering soil C in desertified areas of the Horqin Sandy Land. 展开更多
关键词 land use land cover soil properties DESERTIFICATION Horqin Sandy Land
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Effects of Plant Types on Physico-chemical Properties of Reclaimed Mining Soil in Inner Mongolia,China 被引量:3
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作者 FU Yao LIN Changcun +1 位作者 MA Jianjun ZHU Tingcheng 《Chinese Geographical Science》 SCIE CSCD 2010年第4期309-317,共9页
A field experiment was conducted in Jungar Banner,Inner Mongolia,China to study the effects of plant types on the physical structure and chemical properties of open-cast mining soils reclaimed for 15 years,and to anal... A field experiment was conducted in Jungar Banner,Inner Mongolia,China to study the effects of plant types on the physical structure and chemical properties of open-cast mining soils reclaimed for 15 years,and to analyze the triggering factors of the soil formation.Results indicate that plant types affect soil-forming process especially in the upper layer (0-20 cm),and the spatial structure of reclaimed plant is the main reason for variability of the soil-forming process.In the upper soil layer at the site reclaimed with mixed plants,the concentrations of soil organic matter (SOM) and soil organic carbon (SOC) are the highest,and they were significantly higher at the sites reclaimed with Leymus chinensis,Caragana sinica,which is mainly due to a large amount of litter fall and root exudation in herbages and shrubs.However,the concentrations of SOM and SOC in the soils at the reclaimed sites are quite low comparing with those in local primary soil,which indicates the importance of using organic amendments during the ecological restoration in the study area. 展开更多
关键词 土壤理化性质 植物种类 内蒙古 矿区复垦 物理化学 中国 土壤有机质含量 土壤形成过程
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Characterization of Some Typical Soils of the Miombo Woodland Ecosystem of Kitonga Forest Reserve, Iringa, Tanzania: Physico-Chemical Properties and Classification 被引量:1
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作者 Hassan Bashiru Shelukindo Balthazar Msanya +3 位作者 Ernest Semu Sibaway Mwango Bal Ram Singh Pantaleo Munishi 《Journal of Agricultural Science and Technology(A)》 2014年第3期224-234,共11页
关键词 森林生态系统 物理化学性质 典型土壤 森林保护区 坦桑尼亚 土分类 表征 可持续管理
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Impact of Seasons on Soil Physico-Chemical Properties and Tea Yields Based on Enriched Sheep Manure Used in Kericho, Kenya
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作者 Rhoda Ruto Syphline Kebeney +1 位作者 John K. Bore David Chemei 《Journal of Agricultural Chemistry and Environment》 2019年第3期184-199,共16页
Tea (Camellia sinensis (L) O. Kuntze) is a perennial crop grown for beverage consumption. Its production is the leading foreign exchange earner in Kenya contributing about 26% foreign exchange and 4% GDP. Nitrogen (N)... Tea (Camellia sinensis (L) O. Kuntze) is a perennial crop grown for beverage consumption. Its production is the leading foreign exchange earner in Kenya contributing about 26% foreign exchange and 4% GDP. Nitrogen (N), Phosphorus (P) and potassium (K) are the recommended nutrients for tea production. However, their continuous use has been reported to have negative effect on soil physico-chemical properties and health. Sheep manure has been recommended in tea production for its soil pH buffering effect and increased tea yields. However, effects of sheep manure enriched with inorganic fertilizer on tea soils and yield have not been conclusively investigated. This study was established at KALRO—Tea Research Institute Kericho in Timbilil estate to determine the impact of seasonal variation on soil pysico-chemical properties and yields on enriched sheep manure used. Randomized complete block design (RCBD) experimental design was adopted with 14 treatments replicated thrice. The treatments were: control with no fertilizer use, NPK at 180 Kgs N/ha/yr, sheep manure only and two enriched sheep manure ratios of 4:1 and 8:1 which translates to a mixture of (4:1) 4 parts of sheep manure and 1 part of D.A.P inorganic fertilizer. Same applied to 8:1 ratio, respectively at rates of 60, 120, 180 and 240 Kgs N/ha once per year. Data were subjected to ANOVA in GenStat statistical package and means separated by Duncan’s multiple range tests at P ≤ 0.05 significance level. Results obtained showed that soil physico-chemical properties and tea yields were influenced significantly (P ≤ 0.05) by treatments applied. Soil available water and organic matter were higher on enriched sheep manure 4:1 at 240 rate used while soil porosity and bulk density were not significantly affected. Total N and P, increased with enriched sheep manure ratio of 4:1 at 240 rate while K+, Ca2+, Mg2+, Mn and pH increased with sole application of sheep manure at rate 180 and enriched sheep manure 8:1 at 180 rate. Tea yields increased with enriched sheep manure 4:1 ratios at the rates of 240. The findings recommend enriched sheep manure 4:1 ratio at 240 rates to be adopted by tea farmers within Kericho region. Further studies involving different geographical locations are proposed. 展开更多
关键词 SEASONS soil Physic-Chemical Properties Enriched SHEEP MANURE Tea YIELDS
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Effects of December 2014 Great Flood on the Physico-Chemical Properties of the Soils in the Kelantan Plains, Malaysia
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作者 Jusop Shamshuddin Qurban Ali Panhwar +3 位作者 Radziah Othman Roslan Ismail Hamdan Jol Melissa Alina Yusoff 《Journal of Water Resource and Protection》 2016年第2期263-276,共14页
Heavy rain falling on land at the upper reaches of the Kelantan River, Malaysia, on December 2014, had resulted in severe soil erosion and untold damages to croplands. The lower reaches of the river were heavily silte... Heavy rain falling on land at the upper reaches of the Kelantan River, Malaysia, on December 2014, had resulted in severe soil erosion and untold damages to croplands. The lower reaches of the river were heavily silted with infertile materials considered unfit for crop production. A study was conducted to explain why the flood phenomenon occurred, to determine the physico-chemical properties of the sediments silted in the Kelantan Plains and to propose measures for soil mitigation. Results showed that the silted sediments were characterized by the presence of quarts, mica, feldspars, kaolinite, gibbsite and hematite believed to come from the top- and subsoil of the upland areas. The sediments’ pH was very low and Al and/or Fe contents were very high, while nitrogen and carbon contents varied from area to area. Soils in the Kelantan Plains badly affected by this great flood needed to undergo proper ameliorative program. The most appropriate measure would be to apply ground magnesium limestone in combination with bio-fertilizer fortified with beneficial microbes that would increase their pH to a level above 5, which consequently eliminates Al<sup>3+</sup> and/or Fe<sup>2+</sup> that causes toxicity to the crops growing on them. The organic material so added would enhance the formation of soil structures. It is advised that the farming communities in the upper reaches of the Kelantan River would have to follow the advice advocated by the Department of Agriculture, Peninsular Malaysia, via MyGAP initiative, in order to sustain agricultural production on their land. 展开更多
关键词 Crop Production Great Flood Heavy Rainfall Silted Sediments soil Properties
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Physico-Chemical Properties of Flour, Starch, and Modified Starch of Two Rice Varieties 被引量:5
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作者 LIN Qin-lu XIAO Hua-xi +3 位作者 FU Xiang-jin TIAN Wei LI Li-hui YU Feng-xiang 《Agricultural Sciences in China》 CAS CSCD 2011年第6期960-968,共9页
The physical and chemical properties of the flours, starches, and modified starches of indica rice and japonica rice were investigated in this paper. Results showed that the swelling powers of flour, starch, and phosp... The physical and chemical properties of the flours, starches, and modified starches of indica rice and japonica rice were investigated in this paper. Results showed that the swelling powers of flour, starch, and phosphate starch [substitution degree (DS)=0.065] of japonica rice were significantly higher than those (DS=0.065) of indica rice. The transmittance of modified starches was highest; and that of flours was lowest. The pasting property investigated with rapid visco analyzer (RVA) indicated that the peak viscosity and breakdown value of paste with high swelling power were high. Furthermore, the effect of protein and amylose content on pasting property were investigated. The results of rheological properties determined using rheological rheometer showed that at the same temperature, the storage modulus (G′ of flour, starch, and modified starch of indica rice was higher than that of japonica rice. For each variety, the G′of flour was the highest, while the G′of modified starch was the lowest. 展开更多
关键词 RICE STARCH viscosity physico-chemical properties RHEOLOGY
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Digital mapping of soil physical and mechanical properties using machine learning at the watershed scale
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作者 Mohammad Sajjad GHAVAMI Shamsollah AYOUBI +1 位作者 Mohammad Reza MOSADDEGHI Salman Naimi 《Journal of Mountain Science》 SCIE CSCD 2023年第10期2975-2992,共18页
Knowledge about the spatial distribution of the soil physical and mechanical properties is crucial for soil management,water yield,and sustainability at the watershed scale;however,the lack of soil data hinders the ap... Knowledge about the spatial distribution of the soil physical and mechanical properties is crucial for soil management,water yield,and sustainability at the watershed scale;however,the lack of soil data hinders the application of this tool,thus urging the need to estimate soil properties and consequently,to perform the spatial distribution.This research attempted to examine the proficiency of three machine learning methods(RF:Random Forest;Cubist:Regression Tree;and SVM:Support Vector Machine)to predict soil physical and mechanical properties,saturated hydraulic conductivity(Ks),Cohesion measured by fall-cone at the saturated(Psat)and dry(Pdry)states,hardness index(HI)and dry shear strength(SS)by integrating environmental variables and soil features in the Zayandeh-Rood dam watershed,central Iran.To determine the best combination of input variables,three scenarios were examined as follows:scenarioⅠ,terrain attributes derivative from a digital elevation model(DEM)+remotely sensed data;scenarioⅡ,covariates of scenarioⅠ+selected climatic data and some thematic maps;scenarioⅢ,covariates in scenarioⅡ+intrinsic soil properties(Clay,Silt,Sand,bulk density(BD),soil organic matter(SOM),calcium carbonate equivalent(CCE),mean weight diameter(MWD)and geometric weight diameter(GWD)).The results showed that for Ks,Psat Pdry and SS,the best performance was found by the RF model in the third scenario,with R2=0.53,0.32,0.31 and 0.41,respectively,while for soil hardness index(HI),Cubist model in the third scenario with R2=0.25 showed the highest performance.For predicting Ks and Psat,soil characteristics(i.e.clay and soil SOM and BD),and land use were the most important variables.For predicting Pdry,HI,and SS,some topographical characteristics(Valley depth,catchment area,mltiresolution of ridge top flatness index),and some soil characteristics(i.e.clay,SOM and MWD)were the most important input variables.The results of this research present moderate accuracy,however,the methodology employed provides quick and costeffective information serving as the scientific basis for decision-making goals. 展开更多
关键词 Machine learning soil physical property soilmechanical property Saturatedhydraulic conductivity soil cohesion soil shear strength.
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Leguminosae plants play a key role in affecting soil physical-chemical and biological properties during grassland succession after farmland abandonment in the Loess Plateau,China
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作者 SUN Lin YU Zhouchang +5 位作者 TIAN Xingfang ZHANG Ying SHI Jiayi FU Rong LIANG Yujie ZHANG Wei 《Journal of Arid Land》 SCIE CSCD 2023年第9期1107-1128,共22页
Leguminosae are an important part of terrestrial ecosystems and play a key role in promoting soil nutrient cycling and improving soil properties.However,plant composition and species diversity change rapidly during th... Leguminosae are an important part of terrestrial ecosystems and play a key role in promoting soil nutrient cycling and improving soil properties.However,plant composition and species diversity change rapidly during the process of succession,the effect of leguminosae on soil physical-chemical and biological properties is still unclear.This study investigated the changes in the composition of plant community,vegetation characteristics,soil physical-chemical properties,and soil biological properties on five former farmlands in China,which had been abandoned for 0,5,10,18,and 30 a.Results showed that,with successional time,plant community developed from annual plants to perennial plants,the importance of Leguminosae and Asteraceae significantly increased and decreased,respectively,and the importance of grass increased and then decreased,having a maximum value after 5 a of abandonment.Plant diversity indices increased with successional time,and vegetation coverage and above-and below-ground biomass increased significantly with successional time after 5 a of abandonment.Compared with farmland,30 a of abandonment significantly increased soil nutrient content,but total and available phosphorus decreased with successional time.Changes in plant community composition and vegetation characteristics not only change soil properties and improve soil physical-chemical properties,but also regulate soil biological activity,thus affecting soil nutrient cycling.Among these,Leguminosae have the greatest influence on soil properties,and their importance values and community composition are significantly correlated with soil properties.Therefore,this research provides more scientific guidance for selecting plant species to stabilize soil ecosystem of farmland to grassland in the Loess Plateau,China. 展开更多
关键词 secondary succession LEGUMINOSAE plant diversity plant community composition soil physical-chemical properties soil biological properties
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Soil seed bank is affected by transferred soil thickness and properties in the reclaimed coal mine in the Qilian Mountains, China
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作者 YANG Jingyi LUO Weicheng +3 位作者 ZHAO Wenzhi LIU Jiliang WANG Dejin LI Guang 《Journal of Arid Land》 SCIE CSCD 2023年第12期1529-1543,共15页
Reclamation of lands abandoned after mining in mountain areas is critical to erosion control,safety from landslides,and ecological protection of mountain ecosystems.However,little is known about alpine coal mine recla... Reclamation of lands abandoned after mining in mountain areas is critical to erosion control,safety from landslides,and ecological protection of mountain ecosystems.However,little is known about alpine coal mine reclamation using the soil seed bank as a potential source for revegetation.We collected samples of persistent soil seed bank for germination experiments from nine reclaimed sites with different soil cover thicknesses and from six control sites in the Qilian Mountains of China.Soil properties of each site were determined(including soil water content,soil available potassium,soil available phosphorus,soil total nitrogen,pH,soil organic matter,soil total phosphorus,and soil total potassium,and soil alkali-hydrolyzable nitrogen),and the relationships of the characteristics of the soil seed bank with soil cover thickness and soil properties were examined.The results showed that the density,number of species,and diversity of the topsoil seed bank were significantly correlated with soil cover thickness,and all increased with the increment of soil cover thickness.Soil cover thickness controlled the soil seed bank by influencing soil properties.With the increase in soil cover thickness,soil properties(e.g.,soil organic matter,soil total nitrogen,etc.)content increased while soil pH decreased.The soil seed bank had the potential to restored the pre-mining habitat at reclaimed sites with approximately 20-cm soil cover thickness.Soil properties of reclaimed sites were lower than that of natural sites.The relationship between the soil seed bank and soil cover thickness determined in this study provides a foundation for improving reclamation measures used in coal mines,as well as for the management and monitoring of reclaimed areas. 展开更多
关键词 soil seed bank soil cover thickness species composition soil properties Qilian Mountains
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Influence of different soil properties on the failure behavior of deposit slope under earthquake after rainfall
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作者 YANG Bing HOU Jiang-rong +1 位作者 ZHOU Zi-hong GOU Jin-cheng 《Journal of Mountain Science》 SCIE CSCD 2023年第1期65-77,共13页
In this study,the influence of soil properties on the failure behavior and mechanism of slope under earthquake after rainfall was studied with shaking table test in the laboratory,in which the failure process of slope... In this study,the influence of soil properties on the failure behavior and mechanism of slope under earthquake after rainfall was studied with shaking table test in the laboratory,in which the failure process of slope and instant responses of water content and pore water pressure were tested.Based on the principle of similarity,a model test was designed.The experimental results showed that soil properties exhibit significant influence on failure mode and failure mechanism of slope.Local flowslide,local failure,and creep flowslide failure modes appear in the slope exposed to only rainfall.However,under earthquake after rainfall,the other three failure modes occur,i.e.,local slip failure,overall slip failure,and shallow scouring and creep flowslide failure.The spatial distribution of water content and pore water pressure are the two key factors leading to slope failure.Furthermore,due to the difference of permeability,the soil properties not only affect the spatial distribution of water content of the slope after rainfall,resulting in the peak pore water pressure which occurs mainly near the foot of the slope and near the bedrock interface in the middle and lower parts of the slope,but also affect the dissipation of excess pore water pressure in the process of earthquake.Finally,it is discovered that different types of soil lead to significant differences in the peak acceleration of slope failure.The critical acceleration of slope with coarse-grained soil is greater than that of slope with fine-grained soil.The critical acceleration of slope failure shows a close relationship with soil properties. 展开更多
关键词 Failure mode Failure mechanism Deposit slope soil properties Earthquake after rainfall
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Mechanical properties of dredged soil reinforced by xanthan gum and fibers
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作者 Dianzhi Feng Bing Liang +4 位作者 Xingxing He Fu Yi Jianfei Xue Yong Wan Qiang Xue 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第8期2147-2157,共11页
Biopolymers have become popular in geotechnical engineering as they provide a carbon-neutral alternative for soil solidification.Xanthan gum(XG)and jute fiber(JF)were selected to solidify the Yellow River dredged soil... Biopolymers have become popular in geotechnical engineering as they provide a carbon-neutral alternative for soil solidification.Xanthan gum(XG)and jute fiber(JF)were selected to solidify the Yellow River dredged soil.The mechanical behavior of solidified dredged soil(SDS)was investigated using a series of uniaxial compression and splitting tension tests at different XG and JF contents and fiber lengths.The results indicate that on the 28th day,the unconfined compressive strength(UCS)values of SDS samples reached 2.83 MPa and splitting tensile strength(STS)of 0.763 MPa at an XG content of 1.5%.When the JF content was greater than 0.9%,the STS of the SDS samples decreased.This is because that the large fiber content weakened the cementation ability of XG.The addition of JF can significantly increase the strain at peak strength of SDS samples.There is a linear relationship between the UCS and STS of the dredged soils solidified by XG and JF.Microanalysis shows that the strength of SDS samples was improved mainly via the cementation of XG itself and the network structure formed by JF with soil particles.The dredged soil reinforced by XG and JF shows better mechanical performance and has great potential for application. 展开更多
关键词 Solidified dredged soil(SDS) Xanthan gum(XG) Jute fiber(JF) Mechanical properties
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Effects of Different Planting Years on Physicochemical Properties and Enzyme Activities in Soil of Rice-Cherry Tomato Rotation
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作者 Xiao Deng Chunyuan Wu +2 位作者 Yi Li Huadong Tan Jiancheng Su 《Open Journal of Ecology》 2023年第6期334-344,共11页
Crop rotation periodicity has always been one of the research focuses currently. In this study, the physicochemical properties, nutrient contents and enzyme activities were investigated in soils from rice-cherry tomat... Crop rotation periodicity has always been one of the research focuses currently. In this study, the physicochemical properties, nutrient contents and enzyme activities were investigated in soils from rice-cherry tomato rotation for one year (1a), three years (3a), five years (5a), seven years (7a) and ten years (10a), respectively. The major objective was to analyze the optimal rotation years of rice-cherry tomato from soil perspective, so as to provide theoretical basis for effectively avoiding continuous cropping obstacles of cherry tomato via studying the response characteristics of soil physicochemical properties, nutrient contents and enzyme activities to planting years of rice-cherry tomato rotation system. The results were as follows: 1) Soil pH value was increased year by year during 1a to 5a, reached the highest value 5.32 at 5a. However, soil acidity was sharply enhanced during 7a to 10a (P P •kg<sup>-1</sup> at 5a. 3) The content of soil available phosphorus was increased year by year with increasing of crop rotation years, and increased by 110% to 173% during 3a to 10a (P P P < 0.05). In conclusion, long-term single rotation pattern of rice-cherry tomato would aggravate soil acidification, prompt soil nutrient imbalance and reduce soil enzyme activity. 5a to 7a would be the appropriate rotation period for rice-cherry tomato, or else it would reduce soil quality, resulting in a new continuous cropping obstacle of cherry tomato. 展开更多
关键词 Rice-Cherry Tomato Rotation Planting Years soil Physicochemical Properties Enzyme Activity
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Evaluation of sensory properties and their correlation coefficients with physico-chemical indices in Turkish set-type yoghurts 被引量:1
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作者 Zehra Güler Young W. Park 《Open Journal of Animal Sciences》 2011年第1期9-15,共7页
Sensory properties and physico-chemical parameters of 10 most popular brands of commercial set-type Turkish yoghurts were evaluated and correlation coefficients between the two indices were investigated. The results i... Sensory properties and physico-chemical parameters of 10 most popular brands of commercial set-type Turkish yoghurts were evaluated and correlation coefficients between the two indices were investigated. The results indicated that increases in volatile compounds (acetaldehyde, 2-butanone, 2-nanonane, ethyl acetate), titratable acidity, ash and fat contents inversely correlated with the overall acceptability score of the yoghurt. However, diacetyl, C4 to C12 free fatty acids, pH, whiteness index and texture positively correlated with overall acceptability of the yoghurt products. It was concluded that the acceptability of the Turkish set-type yoghurts is mainly governed by the fifteen volatile compounds as well as the physico-chemical properties determined. Thus, the overall acceptability of the yoghurts was not influenced by a single characteristic, but rather by complex in nature. 展开更多
关键词 TURKISH set-type YOGHURT SENSORY properties physico-chemical parameters correlation coefficient
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