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Visible and Near-Infrared Diffuse Reflectance Spectroscopy for Prediction of soil Properties near a Copper Smelter

Pedosphere 2012年第3期22卷 351-366页

作者： XIE Xian-Li PAN Xian-Zhang SUN Bo Key Laboratory of soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) State Key Laboratory of soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China)

Spatial and temporal monitoring of soil properties in smelting regions requires collection of a large number of sam- ples followed by laboratory cumbersome and time-consuming measurements. Visible and near-infrared diffuse reflectance spectroscopy （VNIR-DRS） provides a rapid and inexpensive tool to predict various soil properties simultaneously. This study evaluated the suitability of VNIR-DRS for predicting soil properties, including organic matter （OM）, pH, and heavy metals （Cu, Pb, Zn, Cd, and Fe）, using a total of 254 samples collected in soil profiles near a large copper smelter in China. Partial least square regression （PLSR） with cross-validation was used to relate soil property data to the reflectance spectral data by applying different preprocessing strategies. The performance of VNIR-DRS calibration models was evaluated using the coefficient of determination in cross-validation （R^2cv） and the ratio of standard deviation to the root mean standard error of cross-validation （SD/RMSEcv）. The models provided fairly accurate predictions for OM and Fe （R2v 〉 0.80, SD/RMSEcv 〉 2.00）, less accurate but acceptable for screening purposes for pH, Cu, Pb, and Cd （0.50 〈 Rcv 〈 0.80, 1.40 〈 SD/RMSEcv 〈 2.00）, and poor accuracy for Zn （R2v 〈 0.50, SD/RMSEcv 〈 1.40）. Because soil properties in conta- minated areas generally show large variation, a comparative large number of calibrating samples, which are variable enough and uniformly distributed, are necessary to create more accurate and robust VNIR-DRS calibration models. This study indicated that VNIR-DRS technique combined with continuously enriched soil spectral library could be a nondestructive alternative for soil environment monitoring.

关键词： heavy metal organic matter partial least squares regression soil environment monitoring spectral preprocessing

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Estimation of Throughfall Erosivity in a Highly Diverse Forest Ecosystem Using Sand-Filled Splash Cups

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Journal of Earth science 2010年第6期21卷 897-900页

作者： Christian Geiβler Peter Kühn 史学正 Thomas Scholten Chair of Physical Geography and soil science Eberhard Karls University Tübingen Institute of soil science Chinese Academy of Sciences

Sand-fflled splash cups were used to study the erosive power of rainfall and throughfall in the humid subtropics of Southeast China. The splash cup measurements yielded precise and reproducible results under both open field conditions and forest vegetation. The splash cups were exposed to specific forest stands of different ages and to selected species （Schima superba, Castanopsis eyrei, Daphniphyllum oldhamii, Lithocarpus glaber） in the Gutianshan （古田山） National Nature Reserve （GNNR）. The results of the measurements under forest vegetation show that the erosive power of throughfall drops to be 2.59 times higher compared to the open field. This accentuates the importance of shrub, herb and litter layers in forest ecosystems to protect the soil against erosion. Coalescing drops from leaves and branches （drips） are responsible for this notable gain in erosive power. Moreover, differences in sandloss between the investigated tree species （deciduous, evergreen） revealed that the erosion potential and the spatial heterogeneity of throughfall are species-specific. This highlights the importance of selecting specific species for afforestation projects considering the prevention of soil erosion.

关键词： Biodiversity and Ecosystem Functioning (BEF)-China biodiversity soil erosion soil erosion experiment splash cup throughfall erosivity.

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Changes in heavy metal contents in animal feeds and manures in an intensive animal production region of China

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Journal of Environmental sciences 2013年第12期25卷 2435-2442页

作者： Hui Wang Yuanhua Dong Yunya Yang Gurpal S.Toor Xumei Zhang Key Laboratory of soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of Sciences soil and Water Quality Laboratory Gulf Coast Research and Education CenterUniversity of Florida Taicang soil Management Station

The 360 feed and manure samples were collected from 150 animal farms in Jiangsu Province, China and analyzed for heavy metals. Concentrations of Zn and Cu in animal feeds were 15.9-2041.8 and undetected-392.1 mg/kg respectively, while Hg, As, Pb, Cd, and Cr in all feeds were below 10 mg/kg. Concentrations of Cu, Zn, and Cr in animal manures were 8.4-1726, 39.5-11379, and 1.0-1602 mg/kg respectively, while As, Cd, Hg, and Pb were 〈 10 mg/kg. The concentration of Cu, Zn, As and Cr in animal feed and manure were positively correlated （p 〈 0.001）, but the Cd, Hg, and Pb were not statistically correlated between the feed and the manure. Concentrations of Cu and Zn were highest in pig feed and manure, followed by poultry and dairy feeds and manures. During 1990- 2008, Cu, Zn, As, Cr, Cd contents increased by 771%, 410%, 420%, 220%, and 63% in pig manure, 212%, 95%, 200%, 791%, and -63% in dairy manure, and 181%, 197%, 1500%, 261, and 196% in poultry manure. Most of the increases occurred from 2002 to 2008, which reflects the extensive use of feed additives after 2002. In contrast, Pb and Hg in manures continuously decreased from 1990 to 2008. The results suggest that the heavy metal contents in animal manure have been greatly increased over 18 years and the contribution of manures to soil should be considered.

关键词： animal manures heavy metal change

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Micromorphology of Surface Crusts in the Knersvlakte,South Africa

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Journal of Mountain science 2009年第2期6卷 189-196页

作者： Sarah-Jane C.Fox Anthony J.Mills Rosa M.Poch Department of soil science Stellenbosch UniversityStellenbosch South Africa Department of Environment and soil science University of LleidaRovira Roure 191 Lleida

soils in the Knersvlakte are particularly prone to crusting and have lower inherent infiltrability than other soils across western southern Africa. Micromorphological techniques were used to examine the structure and porosity of soil crusts in the Knersvlakte to ascertain why crusting is so intense in this region. Quantile regression using boundary lines was employed to examine the relationships between infiltrability and soil properties for all samples （n = 67）. This analysis showed that infiltrability is potentially maximal at low water- dispersible ＇clay plus silt＇ content and low silt content （r^2 = 0.72 and 0.64; respectively, n = 67）（Figure 2）. The strength of crusts, pH, EC, clay mineralogy, and water-dispersible clay, silt and ＇clay plus silt＇ content were compared, and a pore analysis using optical microscopy was undertaken on images of six soil thin sections （n = 6）（circular and parallel polarizers）. Pore analysis was further undertaken on five horizontal slices of equal dimensions taken through each soil thin section. The porosity samples with low infiltrability （〈 100 mm·hr^-1, n = 4） had greater crust strength, lower porosity （both total and in the least porous slice） and greater water-dispersible ＇day plus silt＇ and silt content than the porosity samples with high infiltrability （〉 100mm·hr^-1, n = 2）. The porosity samples with low infiltrability showed a trend of lower pH and greater water dispersible clay percentage. Porosity varied within the porosity samples due to the presence of dense clay/silt bands （〈 0.5 mm in width） with relatively few air vesicles. The porosity samples with horizontal slices of low porosity （but large numbers of air vesicles） had low infiltrability, while those without slices of low porosity （and relatively few air vesicles） had high infiltrability. We conclude that the intense crusting and resultant low infiltrability of soils in the Knersvlakte appears to be related to the formation of thin, dense clay/silt bands in the

关键词： Infiltrability optical microscopy porosity air vesicles

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Site-Specific Nitrogen Management in Dry Direct-Seeded Rice Using Chlorophyll Meter and Leaf Colour Chart

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Pedosphere 2015年第1期25卷 72-81页

作者： Ali Mohamed ALI Harmit Singh THIND Sandeep SHARMA YADVINDER-SINGH Department of soil science Punjab Agricultural University Department of soil Fertility and Microbiology Desert Research Centre

The need to maintain high rice yields and improve fertilizer nitrogen(N)-use efficiency has fueled the use of tools such as leaf colour chart(LCC) and chlorophyll meter(SPAD meter) in managing fertilizer N based on colour of the leaf. Field experiments were conducted during 2011 to 2013 at Ludhiana, India to assess the need for basal N application and to establish critical threshold values of leaf greenness as measured by LCC and SPAD meter for formulating strategies for in-season management of fertilizer N in dry direct-seeded rice(DDSR). Avoiding application of N at sowing did not adversely affect rice grain yield, indicating that basal N application in DDSR was not necessary and might lead to reduced N-use efficiency. Monitoring N uptake rate during the growing season of DDSR suggested that N uptake rate peaked at the two growth stages: maximum tillering(42 to 56 days after sowing(DAS))and panicle initiation stages(70 to 84 DAS). Using the Cate-Nelson procedure, critical LCC and SPAD meter values for fertilizer N application worked out to be 4 and 37, respectively. Real-time fertilizer N management strategy based on applying 30 kg N ha-1whenever SPAD meter or LCC readings fell below the critical values maintained optimum rice yields along with higher N-use efficiency than that observed by following blanket recommendation for fertilizer N in the region. The fixed-time variable-dose strategy consisted of applying prescriptive doses of 20 kg N ha-1at 14 DAS and 30 kg N ha-1at 28 DAS and corrective doses of 30, 40 or 50 kg N ha-1at 49 and 70 DAS depending upon LCC shade to be ≥ 4, 4–3.5, or < 3.5 and SPAD meter readings to be ≥ 40, 40–35, or< 35, respectively. This strategy also resulted in optimal rice yield along with higher N-use efficiency as compared to the blanket recommendation. This study revealed that in DDSR, fertilizer N could be managed more efficiently using the tools of LCC and SPAD meter than the current blanket recommendation.

关键词： basal N application critical value grain yield leaf greenness N-use efficiency

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Origin of Sulfur and Mode of Gypsum Formation in Central Iraqi soils

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Journal of Mountain science 2013年第5期10卷 734-742页

作者： Sabar Rahi Jasem ALJEBOORY Ahmad MUHAIMEED MohammadHady FARPOOR KA SALIeM soil science Department College of AgricultureUniversity of Baghdad soil science Department College of AgricultureShahid Bahonar University of Kerman Ministry of Agriculture

The δ18O and 8D values of gypsum crystallization water together with δ18O and 834S of sulfates were used as reliable techniques to study source of sulfur and mode of gypsum formation in selected central Iraqi soils. Six representative pedons on different geologic units were studied. The slope of 3.9 for δ18O and 8D plot of gypsum crystallization water showed that evaporation was the major process of gypsum deposition in the study area. The mean 834S value of ＋17.58 %0 showed that Cretaceous sea sulfate followed by Tertiary is the source of sulfur in studied soils. The heavier 834S value （＋17.58 %0） of the study area compared to central Iran （＋13.5 %） proved that gypsum in central Iraq soils has been formed in the later stage of evaporation and that Iraqi landforms were cut off from the Tethys seaway after central Iran was evolved.

关键词： Sulfur geochemistry Gypsumcrystallization water Tethys Sea Iraq

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Cadmium speciation as influenced by soil water content and zinc and the studies of kinetic modeling in two soils textural classes

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International soil and Water Conservation Research 2020年第3期8卷 286-294页

作者： Farzad Rassaei Mehran Hoodaji Seyed Ali Abtahi Department of soil science Isfahan(Khorasgan)BranchIslamic Azad UniversityIsfahanIran Department of soil science Shiraz UniversityShirazIran

Background and aims:Since few studies have existed in the literature about the effect of zinc(Zn)on cadmium(Cd)chemical forms in ***,this study has been performed to determine the impact of Zn on cadmium Cd chemical forms in two soil textural classes in Fars province-Iran at two soil water content(SWC)(flooded soil water content(FSWC)and field capacity soil water content(FCSWC))and study the kinetic modeling of *** and materials:Variables were three levels of Cd(0,30 and 60 mg kg-1 of soil as CdSO4·8H2O),three levels of Zn(0,5 and 10 mg kg-1 of soil as Zn-EDTA)three level Incubation times(2,4 and eight weeks),two soil textural classes(clay and sandy clay loam)and two *** randomized completed block design(RCBD)was used for this *** Tessier sequential extraction method was used to determine the Cd concentration in(WsEx),(Fe-MnOx),(Car),(Om)and(Res)chemical ***:In the FSWC,Zn reduced the Cd concentration in Fe-MnOx,Car and Om forms and increased the WsEx but had no significant effect on the Res *** in the Cd chemical forms under the in-fluence of Zn in both soils followed a similar *** the FCSWC,Zn reduced the Cd concentration Car and Om forms and increased the Cd concentration in the Fe-MnOx and WsEx forms while had no sig-nificant effect on Res form in the sandy clay loam *** the clay soil adding Zn reduced the Cd con-centration in Car and Om fractions and increased the Fe-MnOx and Res forms while has no significant effect on WsEx *** competitive transport and adsorption Interactions between these two ions caused the changing in the Cd concentration in its chemical *** reduces the Cd concentration in the forms which are easily released into the soil solution from where they can be absorbed by *** power function kinetic mode is the best fitted model which can describe the Cd adsorption in our soil *** clay and organic compounds control the Cd adsorption in *** higher rate of C

关键词： Cadmium Chemical forms Field capacity Flooding condition Kinetic model Sequential technique soil water content Zinc

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Effects of Rice-Wheat Rotation and Afforestation on Microbial Biomass Carbon in Coastal Salt-Affected soils of Eastern China

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Pedosphere 2017年第5期27卷 938-948页

作者： JIN Wenhui YANG Jingsong YAO Rongjiang YU Shipeng LIU Meixian XIE Wenping State Key Laboratory of soil and Sustainable Agriculture Nanjing Institute of Soil Science Chinese Academy of Sciences

Rice-wheat rotation and poplar afforestation are two typical land use types in the coastal reclaimed flatlands of eastern China. This study investigated two rice-wheat rotation lands （one reclaimed from 1995 to 2004 and cultivated since 2005, RW1, and the other reclaimed from 1975 to 1995 and cultivated since 1996, RW2） and a poplar woodland （reclaimed from 1995 to 2004 and planted in 2004, PWl） to determine the effects of land use types and years of cultivation on soil microbial biomass and mineralizable carbon （C） in this coastal salt-affected region. The results showed that the soil in PWl remained highly salinized, whereas desalinization was observed in RWl. The total organic C （TOC） in the top soil of PWl and RW1 did not show significant differences, whereas at a soil depth of 20-30 cm, the TOC of RWl was approximately 40%-67% higher than that of PWl. The TOC of 0-30-cm soil in RW2 was approximately 37% higher than that in RW1. Microbial biomass C （MBC） and mineralizable C （MNC） exhibited the trend of RW2 〉 RWl 〉 PWl. Sufficient nutrition with more abundant C substrates resulted in higher MBC and MNC, and soil respiration rates were negatively correlated with C/N in RWl and RW2. Nutrient deficiency and high salinity played key roles in limiting MBC in PWl. These suggested that rice-wheat rotation was more beneficial than poplar afforestation for C accumulation and microbial biomass growth in the coastal salt-affected soils.

关键词： carbon availability flatland land use mineralizable carbon nutrition availability total organic carbon

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Modeling Runoff from Semi-Arid Agricultural Lands in Northwest Iran

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Pedosphere 2014年第5期24卷 595-604页

作者： A.R.VAEZI Department of soil science Agriculture Faculty University of Zanjan

Transformation of rainfall into runoff over an area is a very complex process which exhibits both temporal and spatial variability;runoff in a defined area can be affected by factors such as topography, vegetation, rainfall characteristics and soil properties. This study was conducted to develop an empirical model using the rainfall characteristics and soil properties for predicting runoff from dry-farming lands in a semi-arid agricultural area in Hashtroud, Northwest Iran. Runoff plots(1.83 m × 22.1 m) in triplicate were installed in thirty-six sloped dry-farming lands in the study area. Runoff under natural rainfalls was measured in each plot during a2-year period. The results showed that runoff for 41 runoff-producing rainstorm events with duration longer than 30 min was largely associated with a rainfall index obtained by multiplying the positive square root of rainfall depth(h0.5) by the logarithm of the maximum 30-minute intensity(LogI30)(R2= 0.81). Runoff significantly varied among the plots(P soil properties(R2= 0.74), i.e., soil permeability(Per) and aggregate stability(AS). A multiple linear regression model was developed between runoff and the rainfall index(h0.5logI30) and the effective soil properties(AS and Per). Evaluation of the model using 34 runoff-producing rainstorm events that occurred during the next two years resulted in high values of the efficiency coefficient and R2(0.88 and 0.91, respectively), which revealed that the model developed in this study could be used in predicting runoff from the dry-farming lands in the semi-arid regions.

关键词： aggregate stability dry-farming lands natural rainfall rainfall depth rainfall index rainfall intensity soil permeability

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Kinetics of Ligand-Controlled Release of Zinc in Acid Sulfate Paddy soils

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Pedosphere 2019年第2期29卷 216-223页

作者： Worachart WISAWAPIPAT Aksarapak PONGPOM Department of soil science Faculty of Agriculture Kasetsart University

The elevated solubility of zinc(Zn) in acid sulfate paddy soils can limit rice production and pose a risk of environmental ***, little attention has been paid to the ligand-controlled release of Zn in these soils. Here we quantified the rate of ligandcontrolled Zn release in Thai acid sulfate paddy soils, using ethylenediaminetetraacetic acid as the extractant. Sequential extractions were performed to obtain quantitative information on Zn fractions contributing to the ligand-controlled mechanisms. The amount of Zn released within 192 h varied significantly(8–43 mg kg^(-1)), which corresponded to 12%–40% of the total soil Zn, indicating that Zn solubility in most soils was relatively low and that Zn mainly occurred as residual phases. The kinetics of Zn release was well described by the power function model(r = 0.65–0.99, median = 0.87). The magnitude of initial Zn release(coefficient a) was significantly(P soils, the dynamics of which have a significant influence on the availability, phytoextraction, and mobility of Zn in terrestrial and engineered environments.

关键词： ethylenediaminetetraacetic acid kinetic release ligand exchange sequential extraction zinc fraction zinc solubility

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