Ibuprofen Sorption to Coastal Plain Soils

Ibuprofen is commonly detected in onsite wastewater systems. Such onsite systems are abundant in coastal plain areas, globally. Coastal plain soils have unique mineralogy. Rapid subsurface transport may occur in coastal plain soils due to their characteristic permeable soils and seasonally high water tables. Laboratory batch sorption studies were conducted on Norfolk, Goldsboro, and Lynchburg, three archetypical coastal plain soils, with varying physicochemical properties, to evaluate ibuprofen sorption. Sorption distribution coefficients (K_D values) across all three soils ranged from 0.63 to 1.26 L kg^?1. Sorption of ibuprofen to Norfolk and Goldsboro soils was able to be modeled using a Freundlich isotherm; however, the Lynchburg soil, was not, likely due to soil heterogeneity. In general, sorption of ibuprofen was influenced by soil organic carbon content.     

黄河冲积平原潮土速效性钾含量的推算

潮土是黄河冲积平原上的主要土壤类型,其质地的水平和垂直分异是造成土壤属性特别是土壤钾素含量差异的主要因素。根据权威部门测定的土壤各个粒级以及速效性钾含量的数据,利用数理统计的方法首先进行土壤机械组成与土壤速效性钾含量的相关分析,结果发现引起土壤速效性钾含量差异的因素主要是<0. 01mm的土壤颗粒,其次是粘粒、粗粘粒和细粉粒。然后用逐步回归分析的方法建立了<0. 01mm土壤颗粒与速效性钾含量之间的数学模型。用此模型推算土壤速效性钾的含量,在相对误差不大于20%的保证下,准确率达85%。文章最后对回归方程作了解释。     

Monitoring of Greenhouse Gas Production on the Landscape Profile of the Vasyugan Swamp

Eurasian Soil Science - This study deals with the analysis of long-term trends in greenhouse gas concentration, emission, and flows in the landscape profile (LP) of the Vasyugan swamp located in...     

三江平原典型湿地土壤中硫的分布特征

本文以三江平原的三种典型类型湿地:小叶樟(Calamagrostisangustifolia)草甸、毛果苔草(Carexlasiocarpa)沼泽、乌拉苔草(Carexmeyeriana)沼泽为研究对象,对其土壤中硫的含量在水平及垂直变化方面进行分析。研究在自然环境下硫的分布特征。经过试验分析和数据处理,得出以下结论:总硫、水溶性硫、吸附性硫、盐酸可溶性硫、盐酸挥发性硫、有机硫含量均为小叶樟草甸<乌拉苔草沼泽<毛果苔草沼泽;别拉洪河、挠力河、鸭绿河、浓江是三江平原四条有代表性的沼泽性河流,流域土壤中的硫素含量为挠力河>鸭绿河>浓江>别拉洪河;在土壤层次上,具有明显的规律性:除盐酸挥发性硫以外,其余各硫组分自上而下含量呈递减趋势;在湿地土壤各形态硫中,有机硫是土壤总硫的主体,盐酸挥发性硫含量最低。总硫与有机硫相关性最显著,达极显著正相关(P=0.01),水溶性硫与盐酸可溶性硫的相关性最差。影响湿地土壤中硫素含量的因素为土壤有机质、土壤pH值、物理粘粒及氧化-还原条件。     

近20年间黄淮海平原典型区盐渍土性质的对比分析

２０００年通过随机选取１９８０年的８８个盐渍土样点中的３３个样点进行对比调查，研究黄淮海冲积平原区曲周县盐渍土壤的全盐量、ｐＨ、有机质、全氮和有效养分的动态变化以及地下水埋深的变动趋势．结果表明，该县耕地盐渍化和脱盐化作用皆存在，原非盐渍土有盐渍化趋势，轻度盐化土有盐渍化加重的趋势，中度、重度盐化上和内陆盐上则经长期改良治理后脱盐化趋势明显．该区盐渍土有机质、全氮和碱解氮含量均有明显提高，有效磷含量有增有减，有效钾含量则明显降低．对区域土壤盐渍化与脱盐化作用影响较大的地下水位明显降低．     

Economic Assessment of Fertility and Reclamation Measures for Secondary Saline and Solonetzic Soils of the Ararat Plain

Eurasian Soil Science - The application of reclamation measures to improve the state and increase the fertility of irrigated secondary saline and solonetzic meadow-brown soils (Anthrosols) of the...     

Neoformations (Nodules and Placic Layers) in Surface-Gleyed Loamy Sandy Soils of the Northern Part of the Tambov Plain

Eurasian Soil Science - In the middle part of the profiles of light gray soils (non-gleyed, deeply gleyed, weakly and strongly gleyed) on silty loamy sandy two-layered deposits of the river...     

冻融作用对三江平原有机土吸附铵根离子及其分配系数的影响

冻融过程会影响土壤团聚体结构及微孔隙,进而影响土壤对阳离子的吸附。然而有关冻融过程对土壤吸附阳离子影响的研究很少。以典型湿地表层有机土壤为对象,通过室内模拟实验,研究了土壤饱和含水量下,冻融过程对有机土吸附低浓度铵根离子的影响。结果表明,冻融作用一般提高了有机土对铵根离子的吸附量,线性方程能较好的拟合低浓度范围氨氮的吸附,而且冻融作用降低了铵根离子吸附量为0时土壤溶液中氨氮的浓度。随着初始氨氮浓度从8.6mg·L-1升高到43.0mg·L-1,冻融条件下氨氮的分配系数从10.3L·kg-1升高到25.6L·kg-1;非冻融对照条件下氨氮的分配系数从7.0L·kg-1升高到19.8L·kg-1。冻融作用导致氨氮的分配系数增加了29.9%~47.3%,但氨氮的分配系数没有出现随冻融次数增加而升高的趋势。     

Amounts and distribution of organic phosphorus in some profiles in tanzania

The amounts and distribution of organic phosphorus in profiles from several soil orders commonly occurring in the tropics have been determined. Organic phosphorus was found to decrease with depth, except in a few profiles where the maximum tended to occur in the second horizon. This was attributed to soil erosion due to wind and water, which had carried away most of the original A horizon. Poor vegetative growth and the effect of seasonal burning of the natural grassland were also considered to be contributing factors in the higher amounts of organic phosphorus in the second horizon of some profiles.The distribution of the organic phosphorus in the profiles is considered to be a function of climate, vegetation and the parent material. The C/P ratio differed from order to order and within profiles, suggesting that the humic material could affect the content and nature of the organic P fraction and that it is thus possible that the chemical form of the organic phosphorus is not the same in all of the profiles.     

Light Gray Surface-Gleyed Loamy Sandy Soils of the Northern Part of Tambov Plain: Agroecology,Properties, and Diagnostics

Light gray soils of Tambov oblast mainly develop from sandy and loamy sandy parent materials; these are the least studied soils in this region. Despite their coarse texture, these soils are subjected to surface waterlogging. They are stronger affected by the agrogenic degradation in comparison with chernozems and dark gray soils. Morphology, major elements of water regime, physical properties, and productivity of loamy sandy light gray soils with different degrees of gleyzation have been studied in the northern part of Tambov Plain in order to substantiate the appropriate methods of their management. The texture of these soils changes at the depth of 70–100 cm. The upper part is enriched in silt particles (16–30%); in the lower part, the sand content reaches 80–85%. In the nongleyed variants, middle-profile horizons contain thin iron-cemented lamellae (pseudofibers); in surface-gleyed variants, iron nodules are present in the humus horizon. The removal of clay from the humus horizon and its accumulation at the lithological contact and in pseudofibers promote surface subsidence and formation of microlows in the years with moderate and intense winter precipitation. The low range of active moisture favors desiccation of the upper horizons to the wilting point in dry years. The yield of cereal crops reaches 3.5–4.5 t/ha in the years with high and moderate summer precipitation on nongleyed and slightly gleyed light gray soils and decreases by 20–50% on strongly gleyed light gray soils. On light gray soils without irrigation, crop yields are unstable, and productivity of pastures is low. High yields of cereals and vegetables can be obtained on irrigated soils. In this case, local drainage measures should be applied to microlows; liming can be recommended to improve soil productivity.     

Vertical dynamics of soil organic carbon and its influence on Chengdu Plain paddy soils from the 1980s to the 2010s

ABSTRACT

The vertical dynamics of paddy soil organic carbon (SOC) play an important role in soil quality and carbon cycling. In this study, we used an exponential decay function to estimate the vertical dynamics of SOC content and determined its influencing factors in a typical paddy soil area of the Chengdu Plain from the 1980s to the 2010s. Our results show an overall increase in SOC stocks at 0–100 cm from 11.8 Tg in the 1980s to 13.7 Tg in the 2010s. SOC content increased at depths of 0–40 cm and declined at depths of 40–100 cm over the past three decades. The exponential decay function parameters C₀ and k significantly increased by 31.4% and 18.2% respectively, which suggests the vertical pattern of SOC distribution changed. The increase in nugget effects of C₀ and k and the decrease in the relative contributions of the parent material, subgroup and distance-to-river indicate that extrinsic factors played increasing roles in the vertical variation of SOC content. Our study concludes that rice planting has led to vertical variations of SOC content and decreased the effects of intrinsic factors on the vertical variation of SOC content of Chengdu Plain paddy soils over the past three decades.     

On the interlamellar complex between montmorillonite and organic substance in certain soil

KODAMA and SCHNITZER (1) have shown that organic substance of the fluvic acid fraction separated from a podzol soil could penetrate into the interlamellar region of montmorillonite. But the natural occurence of such a complex has not been observed yet (2).     

Soils are back on the global agenda

In the 1990s and early 2000s, there was widespread pessimism on the status of soil science in most parts of the world. This was mainly due to dwindling research budgets, reduced number of students and the overall perception that soil science and pedology were dead and buried. Renewed interest in agriculture for food, feed and fuel has brought soils back onto the global research agenda. Soil erosion, nutrient depletion and pollution are key issues brought up in many recent reports by UN and other international organizations. The need for up‐to‐date and fine resolution soil information and the revival of soil research is highlighted and prioritized in several studies. There is increased interest in soils in the popular press and media, and soils have entered the policy arena. For the global soil science community, there are challenges ahead and there is a direct need to educate a new generation of soil scientists.     

Spatial variability and potential controls of soil organic matter in the Eastern Dongting Lake Plain in southern China

Journal of Soils and Sediments - Information related to spatial distribution and dominants of soil organic matter (SOM) is critical for evaluating soil quality and assessing the carbon...     

Quantitative Estimates of Paleoenvironmental Changes in the Late Holocene in the South of the East European Plain as Recorded in the Magnetic Properties of Soils

Eurasian Soil Science - Information about the past evolutionary changes in the soil cover is essential as a retrospective basis for long-term forecasts of soil development under the changing...     

Inorganic and organic sulfur profiles in nine Sphagnum peat bogs in the United States and Czechoslovakia

Depth profiles of total S, organic S, soluble SO ₄ ^2? -S, FeS, and FeS₂ were characterized for Sphagnum-derived peat cores collected from 9 sites. Marcell S-2 Bog (MN), Tamarack Swamp (PA), Cranesville Swamp (MD/WV), and Big Run Bog (WV) receive water from precipitation and upland runoff; atmospheric S deposition is 13, 47, 54, and 114 mmol m^?2, yr^?1, respectively. McDonald's Branch Swamp (NJ) is predominantly groundwater fed. Tub Run Bog (WV) and Allegheny Mining Bog (MD) receive augmented SO ₄ ^2? inputs through acid coal mine drainage. Jezerní slat' and Bo?í Dar Bog in Czechoslovakia receive atmospheric S inputs of 33 and 243 mmol m^?2 yr^?1, respectively. In the peat from all sites except Allegheny Mining Bog, where the substantially augmented SO ₄ ^2? input was reflected in an unusually high dissolved SO ₄ ^2? pool in the surface peat, organic S (probably mostly carbon bonded S) was the dominant S fraction; FeS₂ was generally the dominant inorganic S fraction. Subsurface peaks in total S, organic S and FeS₂-S in peat from the runoff water fed sites were interpreted as indicative of depth-dependent patterns in S reduction/oxidation and in S immobilization/mineralization. Unless SO ₄ ^2? inputs to a site are tremendously augmented (e.g., Allegheny Mining Bog), the rapid turnover of the dissolved SO ₄ ^2? pool combined with the relative stability of the other inorganic and organic S pools, apparently functions as an effective buffer against site differences in S inputs, leading to a general similarity in vertical S profiles in the peat deposits.     

Bacterial Biodiversity in Soil with an Emphasis on Chemically-Contaminated Soils

Microorganisms isolated from soil are sources of known and new microorganisms and genetic material. This review examines general principles of soil bacterial biodiversity, limitations in sampling soils, and examples of bacterial diversity in chemically-contaminated soils. Both conventional and molecular methods used to assess microbial biodiversity in soils will be addressed as well as selected examples of the effects of organic and inorganic pollutants on soil microbial diversity.     

Adsorption complex,pH relationships in some acid mediterranean forest soil profiles

Acid soils in some mediterranean forests were investigated for the composition of the adsorption complex and the gradients in soil pH. The effective CEC (235–838 mmol_c kg^?1) and base saturation (93–98 %) are highest in ectorganic horizons. In the mineral horizons the effective CEC (23–52 mmol_c kg^?1) and base saturation (11–40 %) are much lower. The exchange complex of mineral horizons consists for 90 (AEh) to 40 percent (Bw2) of organic matter. The effective CEC of the mineral clay fraction is low (60 mmol_c kg^?1 clay). The clear trends in soil pH within the ectorganic layer of deciduous and sclerophyllous oak forests are attributed to vertical spatial separation of nitrogen mineralization (ammonification and strongly impeded nitrification) and nutrient uptake by roots (mainly NH₄). This leads to a high effective CEC in the fermentation layer and acidification of the uppermost part of the mineral soil. In contrast to the situation in temperate forests this process is impeded in mediterranean coniferous forests, where litter decomposition is extremely slow and both proton production and consumption take place in the organic rich mineral horizon.     

Biochemistry of lignin in soils of periodic excessive moistening (from the Example of Agrogray Soils in Opolie Landscapes of the Russian Plain)

Tissues of Angiospermae (deciduous arborous and herbaceous plants) were found to take part in the formation of humus in the agrogray soils. The proportions of lignic phenol contents between the soils did not change neither upon their plowing, no their drainage. Within the catenas studied, the maximal accumulation of phenol compounds takes place in the soils of the mesodepressions with long-term reduction conditions and in the soils of the microdepressions with spring perched water on two levels. In the Fe-Mn nodules of the agrogray soils, lignin of higher plants was found. Its fractional composition was correlated with the predominant vegetation. With the increasing size of the nodules, the amount of products of lignin oxidation in the nodules decreased due to its mineralization. Drainage caused a deep transformation of lignin in the Fe-Mn nodules, especially in the coarse fractions of concretions. The mineralization of lignin aromatic compounds under aerobic conditions was accompanied by the significant increase in the share of phenol acids.