Extinct plants of Israel

As a result of rapid land development in Israel during the past three decades, some 26 species of higher plants, about one percent of the local flora, have become extinct. In addition to listing such species, this paper deals with the ecological implications of this finding. Recommendations for the prevention of further damage to the local flora, and rare plants in particular, are given.     

施用鸡粪后土壤磷的累积特征

根据不同方式计算鸡粪施用量,进行连续6茬蔬菜施用鸡粪田间试验,研究农田土壤中磷的累积特征。结果表明:土壤中全磷、树脂态磷、碳酸氢钠提取态磷、氢氧化钠提取态磷和稀盐酸提取态磷含量均随着鸡粪用量的提高而显著提高,且含量增幅随着种植茬数的增加而提高,故在生产实践中以作物需磷量配施鸡粪较优,否则由此所引起的土壤盈余磷素流失或淋失对地表水和地下水水质的潜在影响风险较大。     

Soil chronosequences in Israel

Chronosequences of Israel soils are summarized. Soil development in the coastal plain is related to the time of the dune deposits while those of the inland valley is related to the formation of the sedimentological terraces. Soil development in the mountains is related to the features and stability of the slope.The properties of young soils resemble those of the parent material. With advancing development the soils are affected by various processes, among them also the accretion of aeolian dust. Leaching is significant already at early stages; in some cases like Hamra and Terra-rossa soils the leaching stage is more advanced in earlier stages than in the final stage of soil development.In advanced stages of soil development the effect of the underlying rock on soil properties is reduced. At the final stage soils on moderate relief in the same climatic zone on different bedrocks resemble each other. This is attributed mainly to the effect of the aeolian dust accretion. The final stage of soil development on moderate relief consists of Grumusols in the northern parts of Israel, grumic dark Brown soils in the semi-arid parts of central Israel, loessial light Brown clay loam and loessial Serozems in the arid parts of the northern Negev and Regs in the extremely arid areas of the Southern Negev and Sinai. Petrocalcic horizons are developed on slopes and terraces where the rate of soil erosion equals that of accumulation of aeolian dust. The formation of petrogypsic horizons in the extremely arid zones is restricted to areas where erosion is negligible.The final stages of soil development exhibit a clear climatic zonality. This zonality differs from the soil zonality in the USSR and the USA due to the special features of dust accretion on the soils of Israel.     

Soils in Japan

There are two ideas in relation to explain soils. The one is to accept soils as material, and the other is, as a natural body.     

Mercury Content of Illinois Soils

Water, Air, & Soil Pollution - For a survey of Illinois soils, 101 cores had been collected and analyzed to determine the current and background elemental compositions of Illinois soils....     

Mercury Content of Illinois Soils

For a survey of Illinois soils, 101 cores had been collected and analyzed to determine the current and background elemental compositions of Illinois soils. Mercury and other elements were determined in six samples per core, including a surface sample from each core. The mean mercury content in the surface samples was 33 ± 20 g/kg soil, and the background content was 20 ± 9 g/kg. The most probable sources of mercury in these soils were the parent material, and wet and dry deposition of Hg⁰ and Hg²⁺ derived from coal-burning power plants, other industrial plants, and medical and municipal waste incinerators. Mercury-bearing sewage sludge or other fertilizers applied to agricultural fields could have been the local sources of mercury. Although the mercury content correlated with organic carbon content or clay content in individual cores, when all the data were considered, there was no strong correlation between mercury and either the organic carbon or the clay-size content.     

Cryptopodzolic Soils in Switzerland

Cryptopodzolic Soils are characterized by a thick blackish-brown mineral horizon rich in organic matter, the dark colour of which masks the morphological characteristics of podzolization. Little is known about the specific site factors that lead to the formation of these soils. Four representative soil profiles from a typical toposequence between 1700 and 500 m above sea level in southern Switzerland, embracing Haplic Podzols, Humic Cambisols and Cryptopodzolic Soils, are described morphologically, chemically and physically. The Cryptopodzolic Soils in this region are characterized by weak to moderate A1 and Fe translocation, and by a uniform incorporation of organic matter deep into the soil. The most prominent feature is the exceptional stability of the soil organic matter with a maximum in the spodic horizon. All these characteristics can be explained by the unique combined effect of a mild, wet climate, an Fe- and Al-rich acid bedrock and a litter layer providing dissolved organic matter rich in polyphenolic substances with strong metal-binding properties.     

Pioneer Mediterranean Shrub Species Revegetating Soils Developed on Mining Soils/Spoils

Spontaneous and autochthonous species of plants growing on degraded and contaminated soils/spoils that survive in such environments show, in general, no symptoms of toxicity. This study compares concentrations of chemical elements in different leaves maturation and in different seasons of several native species in a massive sulphide in an abandoned mine area. The objective is to evaluate if these species can play an important role on the stabilization of degraded soils and mine spoils. Total concentrations of chemical elements were great in soils. However, in general, only <1% of the total concentration was extracted by DTPA or ammonium acetate solutions. Total and available fraction of the chemical elements has similar behaviour between soil sites. Mature leaves have higher concentrations of As, Cu, Fe, Mn, Pb and Zn than younger ones. An opposite behaviour occurs with S. Winter and spring variations in most chemical elements concentrations in the plant leaves are not significantly different, except for As. Elemental concentrations of plant leaves are independent of the same elements concentrations (total and available fraction) in soils where plants have grown. The concentrations of As, Cu and Pb in plant leaves were below the level of risk to be ingested by grazing animals, although soils are above the reported thresholds. Therefore, all studied plant species can be considered for phytostabilization programmes, but the use of the land for pasture may not be a solution considering that animals ingest soil along with herbage. Copyright © 2016 John Wiley & Sons, Ltd.     

恒电荷土壤与可变电荷土壤K+的吸附特性

对我国 3种典型可变电荷土壤和 4种恒电荷土壤在不同 K 浓度和 p H下 K 的吸附特性进行了研究。结果表明 ,两类土壤 K 吸附量均随平衡 K 浓度增加而增加 ,在低浓度 (添加K 0 .1～ 1.0 mmol/ L )时两者符合线性 ,在高浓度 (添加 K 0 .5～ 5 .0 mmol/ L )下两者符合Langmuir方程。L angmuir方程的参数 K两类土壤间差异不大 ,但以可变电荷土壤 >恒电荷土壤 ,说明前类土壤 K吸附结合能较大 ,吸附 K 不易解吸 ,K 有效性较低。p H降低使土壤 K 吸附量减少 ,但恒电荷土壤与可变电荷土壤减少的机理不同 ,前者主要是由于 H 与 K 的竟争吸附 ,而后者主要是由于表面负电荷减少而引起的电性引力的改变。     

Comparative Analysis of Bacteriophages and Bacteria Removal in Soils and Pyrophyllite-Amended Soils: Column Experiments

The objective of the present study was to investigate the transport and removal of Escherichia coli, Bacillus subtilis, Staphylococcus aureus, bacteriophage MS2, and bacteriophage Phix174 in the soils and pyrophyllite-amended soils. Laboratory columns experiments were performed under saturated flow conditions. Our results showed that bacteriophages passed through the soils more easily than bacteria under the given experimental conditions (pulse injection?=?15 min, flow rate?=?0.5 mL/min, column length?=?20 cm, inner diameter?=?2.5 cm, pH?=?7.6, electrical conductivity (EC)?=?150.1 μS/cm); the log removals of bacteria were in the range of 0.44 to 1.72, whereas the log removals of bacteriophages were between 0.01 and 0.13. Our results also demonstrated that the transport of bacteria and bacteriophages in the soil columns could be reduced considerably in the presence of pyrophyllite. Under the same column experimental conditions above, the log removals for MS2 and Phix174 in 50% soil?+?50% pyrophyllite were 2.64 and 3.05, respectively, whereas the log removals in 100% pyrophyllite were 5.70 for MS2 and 5.10 for Phix174; those values were far greater than the log removals in 100% soil (MS2?=?0.063, Phix174?=?0.128). Additional column experiments (step injection, flow rate?=?0.3 mL/min, column length?=?30 cm, inner diameter?=?2.5 cm, solution pH?=?8.4, EC?=?39.8 mS/cm) showed that the log removals for B. subtilis (1.72) and Phix174 (1.48) in the pyrophyllite were greater than those in the soil (B. subtilis?=?1.41; Phix174?=?0.39). This study demonstrated that the pyrophyllite amendment method could be used for protecting groundwater from microbial contamination by animal carcass burial soils.     

塑性土壤的弯曲破碎

弯曲加载是需要最小力及最少能耗使塑性土壤破碎的一种有效的加载方式。进一步的试验表明，使用由旋转切割刀片和支承板组成的弯曲加载装置能很好地产生弯曲破碎，只要支承板和旋转刀片的位置选择合适，其切割阻力及能耗与在水田耕作中得到广泛应用的旋耕刀片相比，约分别为后者的５０％～６５％和２０％。     

Adsorption of Cadmium by Indian Soils

Adsorption behaviour of cadmium (Cd) in soils is an important process which exerts a major influence on its uptake by plant roots. Thirteen soils from various parts of India (tropical region), their pH ranging from 4.2 to 8.4, were subjected to Cd treatment at various concentrations (1 to 100 μg ml-1) and equilibrated at room temperature (25 ± 1 °C). The Cd adsorbed by each soil was calculated as the difference between the amount of Cd present in the solution initially and that remaining after equilibration. Results indicated that the adsorption capacity of the soils for Cd increased with an increase in the pH or alkalinity of the soils. The rate of adsorption was, however, found to decrease with increased pH. All the 13 soils used in this study followed linear and Freundlich adsorption isotherms with highly significant positive correlations (r). The neutral and alkaline soils also followed the Langmuir adsorption isotherm, the adsorption maxima being lowest for the neutral soil and highest for the alkaline soil. The adsorption data, in general, indicated that Cd was in a fixed form at higher pH levels. The results are generally similar to those of the temperate regions; however, Cd adsorption capacity of tropical vertisols was comparatively higher than those of temperate vertisols.     

Uranium Solubility of Carbonate-Rich Uranium-Contaminated Soils

A 300 d solubility study involving two carbonate-rich, uranium-contaminated soils from the Department of Energy's Fernald Environmental Management Project site was conducted to predict the behavior of uranium during on-site remediation of these soils. Geochemical modeling was performed on the aqueous species dissolved from these soils following the solubility measurements to predict the on-site uranium leaching and transport potential. Results showed that the soluble levels of the major components (total uranium, calcium, magnesium, and carbonate) increased continually for the first 4 weeks. After the first 4 weeks, these components either reached a steady-state or continued to increase linearly throughout the study. Soluble uranium levels of both soils and their correlation with alkalinity was strongly mediated by the source term of the contamination. Geochemical modeling predicted and anion exchange experiments confirmed that uranyl-carbonate complexes were the most stable and abundant complexes. Further modeling showed that uranium solubility in these soils and in onsite groundwater wells is controlled by UO₂(H₂PO₄)₂, but is also mediated by complexation with carbonate and the oxidation state of the uranium. For assessing the risk related to off-site transport of uranium, it should be recognized that the solubility of uranium-bearing minerals is the critical factor in controlling uranium solubility of these soils rather than sorption/desorption processes as measured by the uranium distribution coefficient (K_d) in these soils.