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... Time-domain reflectometry (TDR) can help observe the initiation and evolution of localized shear planes in both rock and soil slopes, and has temporal and spatial resolutions suitable for landslide monitoring. An improved and standardized technical guide for TDR cable installation and data interpretation is needed to utilize it better. TDR technique involves sending an electromagnetic pulse into a ...
anthropogenic soiltypes, etc ; Urochloa decumbens; cerrado; grasses; Show all 4 Subjects
Abstract:
... Plant–animal interactions may facilitate biological invasions. The African grass Urochloa decumbens is an aggressive invader in the Cerrado. We demonstrate that native ants are dispersing the seeds to short distances, allowing the gradual spread of the invasive to sites without the need of great anthropogenic soil disturbances. Abstract in Portuguese is available with online material. ...
soiltypes, etc ; agriculture; electronics; geometry; temporal variation; texture; China; Show all 7 Subjects
Abstract:
... With the rapid development of remote sensing (RS) technology, remote sensing images provide an important data basis for soil type mapping. In remote sensing images, temporal factor is difficult to obtain directly, and the rich geometric features are not used adequately. Multi-temporal remote sensing data could effectively reflect the temporal variation of ground objects, while how to extract multi ...
soiltypes, etc ; ecological restoration; pollution; research; rivers; temperature; vegetation cover; Show all 7 Subjects
Abstract:
... The influence of factors on vegetation changes in different regions is still largely unknown. We applied the geographic detector, a new spatial statistical method, to study the interactive effects of factors on the spatial patterns of normalised vegetation index (NDVI) changes and determine the optimal characteristics of key impact factors beneficial to vegetation growth. Our results show that fro ...
soiltypes, etc ; food production; heavy metals; industrialization; pollution; Caribbean; Cuba; Show all 7 Subjects
Abstract:
... Cuba is a country with considerable potential for economic growth, and special efforts are made to increase the agricultural output. As food production depends on the quality of soils, heavy metal concentrations were measured in 39 soils in the province of Mayabeque, Cuba, and interpreted in light of anthropogenic activities and pedogenic conditions (soil type and properties). With median concentr ...
soiltypes, etc ; Cenchrus americanus; bioavailability; food chemistry; iron; millet flour; vanadium; Show all 7 Subjects
Abstract:
... A controlled in-vitro experiment was conducted to determine the bioaccessibility of extrinsic soil iron in pearl millet contaminated with typical Malawian soils. Pearl millet was contaminated with soils at ratios typically encountered in real life. Iron concentrations of soil-contaminated flour increased such that soil-derived iron contributed 56, 83 and 91% of the total iron when the proportions ...
soiltypes, etc ; adsorbents; adsorption; arsenates; mass transfer; water; water treatment; China; Show all 8 Subjects
Abstract:
... The removal, and its mechanism, of arsenate from aqueous solutions was investigated using Yunnan red soil. A series of adsorption experiments was designed to disclose the effect of key factors (soil types, soil/solution rates, initial arsenate concentrations, and shaking speeds) on the adsorption capacity of Yunnan red soil for arsenate. The soil/solution ratio was optimized as 0.05 g/100 mL to ba ...
soiltypes, etc ; Landsat; agriculture; climate; groundwater; income; saffron; soil salinity; soil water; Show all 9 Subjects
Abstract:
... Recent continuous droughts and decreasing ground water tables have prompted efforts to improve irrigation schedules and introduce crops that need less water. A study was recently conducted to determine suitable zones for saffron in Miyaneh using Landsat-8 images and the weighted linear combination (WLC) method. Climatic and geographical indices for saffron cultivation in the region were for soil t ...
soiltypes, etc ; Cervus elaphus; animal performance; deer; diet; habitats; longevity; Iberian Peninsula; Show all 8 Subjects
Abstract:
... Teeth root morphology and integrity are essential to provide appropriate attachment, allowing for continuous and functional movement, with implications for adequate food processing, animal performance, and longevity. We studied the occurrence of supernumerary roots in mandibular molariform teeth of red deer (Cervus elaphus Linnaeus, 1758) from seven separate populations spanning a range of latitud ...
soiltypes, etc ; climate; databases; introduced plants; models; seed dispersal; Andes region; Chile; Show all 8 Subjects
Abstract:
... Alien plant species are colonizing high-elevation areas along roadsides. In this study, we evaluated whether the distributions of alien plants in the central Chilean mountains have reached climatic equilibrium (i.e., upper distribution limits consistent with their climatic requirements). First, we evaluated whether the upper elevational limits of alien plants changed between 2008 and 2018 based on ...
soiltypes, etc ; capillary fringe; environment; gasoline; mathematical models; nomogram; radon; soil air; Show all 8 Subjects
Abstract:
... In the last decades radon (Rn) has been widely proposed as a naturally occurring tracer for non-aqueous phase liquids (NAPL) in the soil. This work examines the feasibility of using soil gas data collected at some distance from the source zone for the application of the Rn deficit technique for the identification and quantification of NAPL contamination. To this end, we used a steady-state 1-D ana ...
soiltypes, etc ; cation exchange capacity; cesium radioisotopes; organic matter; radioactivity; spatial distribution; China; Show all 7 Subjects
Abstract:
... The source and vertical distribution of ¹³⁷Cs,²³⁹⁺²⁴⁰Pu and ²⁴¹Am activity concentrations in a soil core from Hunan Province, China were investigated. The maximum ¹³⁷Cs and ²³⁹⁺²⁴⁰Pu activity concentrations were 15.45 ± 0.76 mBq/g and 0.819 ± 0.066 mBq/g, respectively. While the maximum ²⁴¹Am activity concentration in samples obtained from the core was 0.341 ± 0.019 mBq/g. The ²⁴⁰Pu/²³⁹Pu atom rat ...
paleosolic soiltypes, etc ; Alfisols; Mollisols; archaeology; humans; pastoralism; religion; soil classification; Egypt; Sudan; Show all 10 Subjects
Abstract:
... Mid-Holocene paleosols within archeological excavations at temples of Ancient Egypt and Sudan are here documented from the field and from publications in order to examine the relationship between particular cults and soils. The principal finding is that the same kind of paleosols were seen at the different temples of the same deity, but different kinds of paleosols at temples of different deities. ...
paleosolic soiltypes, etc ; Holocene epoch; Japan; Pleistocene epoch; Sasa; grasslands; paleobotany; palynology; phytoliths; Show all 9 Subjects
Abstract:
... Phytolith records in paleosols provide valuable information on past vegetation in situ, especially for herbaceous plants. Although vegetation transition between the terminal Pleistocene and early Holocene in the southernmost parts of mainland Japan has been examined, detailed information on herbaceous plants during the period is scarce. Therefore, this study examined phytolith records in paleosols ...
soiltypes, etc ; Castanea; climate; diagnostic techniques; geography; humus; museums; permafrost; soil classification; steppes; Show all 10 Subjects
Abstract:
... Cryoaridic soils were proposed to be identified as an individual genetic soil type by Vladimir Volkovintser in the 1970s. Volkovintser argued that the specific properties of these soils are in good agreement with the soil-forming factors: ultracontinental climate, cryoxerophytic steppe or tundra-steppe vegetation, dry permafrost, and skeletal parent material. In cryoaridic soils, the properties of ...
soiltypes, etc ; alkalinity; groundwater; groundwater contamination; guidelines; sediments; vadose zone; water quality; Pakistan; Show all 9 Subjects
Abstract:
... Groundwater is the drinking water source for the majority of rural settlements of district Nowshera, Khyber Pakhtunkhwa, Pakistan. The study aimed to analyze the groundwater quality and its vulnerability to pollution and to develop its spatial distribution mapping. For this purpose, forty-eight groundwater samples were collected from dug wells, tube wells, and hand pumps of sixteen villages and an ...
soiltypes, etc ; geostatistics; greenhouses; polders; risk management; seasonal variation; uncertainty; water management; water table; Show all 9 Subjects
Abstract:
... Information on water table depth (WTD) in polder areas and wetlands is important in, for example, estimating emissions of greenhouse gases, assessing the agricultural and ecological potential, and flood risk management. The seasonal variation of WTDs is summarized with averages of the yearly highest (shallowest) and lowest (deepest) water tables (MHW and MLW). These characteristics show short-dist ...
paleosolic soiltypes, etc ; Holocene epoch; cold; monsoon season; research; river valleys; summer; winter; China; Show all 9 Subjects
Abstract:
... Situated in the Salawusu River Valley in the southeast of China’s Mu Us Desert, the Milanggouwan stratigraphical section MGS1 has recorded 11 sedimentary cycles, consisting of alternations between dune sands and fluvial or lacustrine facies. This paper analyzed the distribution of grain-size and Zr/Rb ratios in the MGS1, which is located in the arid and semi-arid areas of North China, and grain-si ...
soiltypes, etc ; Landsat; entropy; landforms; landscapes; remote sensing; soil classification; statistical analysis; texture; China; Show all 10 Subjects
Abstract:
... The scientific selection of environmental covariates is an important factor that affects the accuracy of digital soil mapping (DSM).An investigation of the influences of different environmental covariates on soil type identification is vital to understand soil development and predictive soil mapping. In this study, the soil groups in the typical plain and hilly areas of the Jiaodong Peninsula in C ...
soiltypes, etc ; bioavailability; citrates; hydrolysis; inositols; malates; oxalates; phospholipids; phytases; soil organic phosphorus; spectroscopy; Show all 11 Subjects
Abstract:
... PURPOSE: Organic anions commonly released from plant roots and microorganisms are widely reported to mobilize soil phosphorus (P). We characterized soil organic P that was mobilized by organic anions and assessed its amenability to hydrolysis by phosphatase enzymes. METHODS: Six soils differing in organic P concentration were extracted with citrate, malate or oxalate solutions and incubated with p ...