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1.
The mobility and migration capacity of Zn in the soil-plant system were studied in a series of pot experiments with barley as a test plant. The parameters of Zn accumulation depending on the metal concentrations in soils and soil solutions were estimated by soil and water culture methods. Experiments with barley in water culture were performed on a nutrient (soil) solution extracted from soddy-podzolic soil (Albic Retisol (Loamic, Ochric)) to which Zn2+ was added to reach working concentrations increasing from 0.07 to 430 μM. Different responses of barley plants to changes in the concentration of Zn in the studied soil were identified. Ranges of the corresponding concentrations in the soil and aboveground barley biomass were determined. Parameters of Zn accumulation by test plants were determined depending on the metal content in soddypodzolic soil and the soil solution. A new method was proposed for evaluating the buffer capacity of soils with respect to a heavy metal (Zn) using test plants (BCS(P)Zn). The method was used to evaluate the buffering capacity of loamy sandy soddy-podzolic soil. The considered methodological approach offers opportunities for using data obtained during the agroecological monitoring of agricultural lands with heavy metals (HMs), including the contents of exchangeable HMs and macroelements (C and Mg) in soils and concentrations of HMs and (Ca + Mg) in plants, in the calculation of the buffering capacity of the surveyed soils for HMs.  相似文献   

2.
Soil as a separate natural body occupies certain area with its own set of spectral characteristics within the RED–NIR spectral space. This is an ellipse-shaped area, and its semi-major axis is the soil line for a satellite image. The spectral area for a bare soil surface is neighboring to the areas of black carbon, straw, vegetating plants, and missing RED–NIR values. A reliable separation of the bare soil surface within the spectral space is possible with the technology of spectral neighborhood of soil line. The accuracy of this method is 90%. The determination of the bare soil surface using vegetation indices, both relative (NDVI), and perpendicular (PVI), is incorrect; the accuracy of these methods does not exceed 65%, and for most of the survey seasons it may be lower than 50%. The flat part of the “tasseled cap” described as the soil line, is not a synonym for the area of the bare soil surface. The bare soil surface on the RED–NIR plots occupies significantly smaller areas than the area of soil line according to Kauth and Thomas.  相似文献   

3.
Eurasian Soil Science - The depiction of soil delineations on a public cadastral map clearly demonstrates the potentialities of large-scale soil mapping. The development of land legislation...  相似文献   

4.
A method to estimate the amount of soil organic carbon (SOC) physically protected within macroaggregates (>200 μm) consists of crushing soil samples and measuring the following SOC mineralization increase. This study investigated the effect of grinding the plant residues during soil crushing on the calculated amount of the protected SOC on two tropical soils (Arenosol and Ferralsol). Incubations of crushed and uncrushed soil samples amended with ground or unground plant residues were conducted. Our results showed that soil crushing increased SOC mineralization and that the presence of plant residues enhanced soil respiration also. The plant residues of the two soils had different decomposition rates, but grinding plant residues did not increase the amounts of cumulative carbon (C) mineralized after the 28 days of the experiment. We propose that the extra C mineralized after soil crushing is due to the breakdown of the soil structure and not to the grinding of plant residues.  相似文献   

5.
Lupachev  A. V.  Gubin  S. V.  Gerasimova  M. I. 《Eurasian Soil Science》2019,52(10):1170-1174
Eurasian Soil Science - The paper is targeted at positioning the cryogenic soils in the recent classification system of Russian soils. An on-line discussion and recent publications demonstrated...  相似文献   

6.
Development of the Hungarian ecological systems model 4M was initiated because the conditions and methods of Hungarian applications are different from the ones that appear in international crop simulation software packages. Because the majority of ecological systems models, just like the CERES model that was used during the development of 4M, do not have phosphorus and potassium modules, 4M initially was incomplete. Based on the work of Hungarian and foreign experts, a nutrient module was developed and was incorporated into the 4M model. The new module was calibrated and validated for phosphorus and potassium using the results of Hungarian aftereffects and long-term experiments. In principle, the nutrient module can be made suitable for simulating the turnover of any kind of nutrient by giving adequate values to the parameters.  相似文献   

7.
INTRODUCTION The insoluble phosphates which can not be directly absorbed by plants are the mai forms of inorganic phosphate in soil. These kinds of phosphates can be solubilized by several species of bacteria which are widely spread in soil especially in rhizosphere where70% of the bacteria are capable of solubilizing inorganic phosphate.  相似文献   

8.
Eurasian Soil Science - The results of a greenhouse experiment with the humus horizon of a sandy loamy soddy-podzolic soil are presented. It was contaminated with heavy metals added with sewage...  相似文献   

9.
The influence of differing soil management practices on changes seen in soil organic carbon (SOC) content of loamy Haplic Luvisol was evaluated. The field experiment included two types of soil tillage: 1. conventional tillage (CT) and 2. reduced tillage (RT) and two treatments of fertilization: 1. crop residues with nitrogen, phosphorus, and potassium (NPK) fertilizers (PR+NPK) and 2. NPK fertilizers (NPK). The results of SOC fluctuated from 9.8 to 14.5 g kg?1 and the tillage systems employed and fertilization status did not have a statistically significant influence on SOC. The SOC content was higher in RT (12.4 ± 0.86 g kg?1) than in CT (12.2 ± 0.90 g kg?1). On average, there was a smaller higher value of SOC in PR+NPK (12.4 ± 1.02 g kg?1) than in NPK (12.3 ± 0.88 g kg?1). During a period of 18 years, reduced tillage and application of NPK fertilizers together with crop residues build up a SOC at an average speed of 7 and 16 mg kg?1 year?1, respectively, however conventional tillage and NPK fertilizer applications caused a SOC decline at an average speed of 104 and 40 mg kg?1 year?1, respectively.  相似文献   

10.
Though knowledge about the distribution and properties of soils is a key issue to support sustainable land management, existing knowledge of the soils in Tigray (Northern Ethiopian Highlands) is limited to either maps with a small scale or with a small scope. The goal of this study is to establish a model that explains the spatial soil variability found in the May-Leiba catchment, and to open the scope for extrapolating this information to the surrounding basalt-dominated uplands. A semi-detailed (scale: 1/40 000) soil survey was conducted in the catchment. Profile pits were described and subjected to physico-chemical analysis, and augerings were conducted. This information was combined with information from aerial photographs and geological and geomorphologic observations. The main driving factors that define the variability in soil types found were: 1) geology, through soil parent material and the occurrence of harder layers, often acting as aquitards or aquicludes; 2) different types of mass movements that occupy large areas of the catchment; and 3) severe human-induced soil erosion and deposition. These factors lead to “red-black” Skeletic Cambisol–Pellic Vertisol catenas on basalt and Calcaric Regosol–Colluvic Calcaric Cambisols–Calcaric Vertisol catenas on limestone. The driving factors can be derived from aerial photographs. This creates the possibility to extrapolate information and predict the soil distribution in nearby regions with a comparable geology. A model was elaborated, which enables the user to predict soil types, using topography, geomorphology, geology and soil colours, all of which can be derived from aerial photographs. This derived model was later applied to other catchments and validated in the field.  相似文献   

11.
Soil greenhouse gas (GHG) emissions are complex, and their study requires considerable sampling of field spatial and temporal differences. Manual and simple automated gas‐collection techniques used at multiple sites during specific time intervals are labor intensive. The objective of this work was to construct a device that can independently collect GHG samples with the accuracy and precision of manually drawn samples. An automated collector of terrestrial systems (ACTS) is a 24‐h, 7‐d/week programmable sampler used in the field for real‐time gathering and containment of soil GHG emissions. The sampler opens and closes an exterior soil gas chamber, mixes gases in the chamber by turning fans on/off, and utilizes programmable circuits to purge the system and draw a sample from the chamber with a pneumatic‐driven syringe. Each sample was stored in an evacuated vial held in a 30‐vial capacity carousel. Vial content was analyzed for carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) at the U.S. Department of Agriculture (USDA)–Agricultural Research Services (ARS) Agroecosystem Management Research Unit (AMRU). A Tracor MT‐220 gas chromatograph (GC) configured with a thermal conductivity detector (TCD) was used for CO2 analysis, and an automated gas‐sampling system (AGSS) attached to a Varian 3700 GC configured with flame ionization detection (FID) and electron capture detection (ECD) was used for CH4 and N2O analysis. Field and laboratory mean values and coefficients of variation (standards and field concentrations of CO2, CH4, and N2O ranging from ambient to 71 kg ha?1 d?1 had coefficients of variation ranging from 1.2 to 4.2%) were similar between ACTS and manually drawn samples. Results showed strong correlation (R2 = 0.81 to 1.00) between sampling methods. The sampler design provides a realistic and inexpensive approach for collecting emission samples while reducing human error associated with adverse sampling conditions and fatigue. The ACTS has potential for use in monitoring and comparing management practices in terrestrial systems to determine their contribution to GHG emissions.  相似文献   

12.
Eurasian Soil Science - The results of morphosubstantive genetic study of a soil–sedimentary sequence with four buried soils in the Boguty River basin (southeastern Altai) are discussed. A...  相似文献   

13.
The cation–anion exchange resin membrane (CAERM) system is one of the most promising alternative methodologies for the assessment of soil phosphorus (P) availability. Nevertheless, the CAERM method has a recommended period of extraction (16 h) that limits its applicability. With the aim to improve the use of CAERM in routine laboratory work, seven extraction times were studied and compared for repeatability and biological accuracy, using 150 samples of soils and covering a wide range of properties. The results showed dissimilar quantities of extractable P, according to the nature of soils and the period of extraction time. On average of all soils, values of extractable P ranged from a 2.4 mg kg?1 and 26.7 mg kg?1 in 0.25‐h and 16‐h extraction times, respectively. Relative to the repeatability aspects, the results reveal a tendency of increasing results with the decrease of the period of extraction, showing coefficient variation (CV) values ranging from 5% (16 h) to 14% (0.25 h). All the extraction periods tested for the CAERM presented highly significant values of r (0.824–0.943) between extractable P and each of the three biological parameters: relative yield of ryegrass, P content, and P uptake. Considering the three biological parameters simultaneously, the best results were obtained for extraction periods of 8 h, 2 h, and 4 h. Based on the results, and considering both practical and accuracy aspects, it is conclude that 2 h of extraction is a valid alternative to the 16‐h standard extraction period for the CAERM methodology.  相似文献   

14.
Eurasian Soil Science - A new view on the genesis and properties of soils in landscapes of the taiga–steppe ecotone in the Selenga Mountains of western Transbaikalia is suggested with due...  相似文献   

15.
Activities of selected soil enzymes (invertase, acid phosphatase, proteinase, catalase, peroxidase and polyphenoloxidase) were determined under different spruce forests with restoration histories of 5, 13, 18, 23, 27 years and an old growth forest over 400 years old in the eastern Qinghai-Tibetan Plateau, China, and their possible use as indicators of ecosystems health were analyzed. Plots 10 × 10 m with 4 replications were established to investigate three hypotheses: soil enzyme activities a) would increase with the restoration process; b) would be greater in surface soils than at lower depths; and c) would be correlated to selected physicochemical properties. Results showed that as the forests developed after restoration, invertase and peroxidase activities usually increased up to the 23 year point. Also soil enzyme activities were associated with surface soils and decreased with depths, suggesting that in earlier restoration stages surface addition of organic fertilizer to soils might be more effective than additions at depth. In the 0-20 cm soil, there were significant correlations (P < 0.01 or < 0.05) between some soil enzyme activities and some selected chemical properties. Therefore, temporal changes in enzyme activities should be included as an indicator when evaluating sustainable forest management practices.  相似文献   

16.
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17.
The effects of simulated acid rain retained in soil on the properties of acid soil and its diminishing by application of ground phosphate rock were investigated by using the sorption method.Results show as follows:(1)For yellow brown soil,the effect of simulated acid rain on the properties of soil with a pH value of 5.9 was relatively small,except a great quantity of acid rain deposited on it.(2) for red soil,the effect of simulated acid rain on the properties of soil was significant.With the increase of the amount of acid deposition,the pH value of soil was declined,but the contents of exchangeable H^ ,Al^3 and Mn^2 and the amount of SO4^1- retention were increased.(3) Many properties of acid soils could be improved by applying ground phosphate rock.For example,pH value of soils and the amounts of available P and exchangeable Ca^2 and Mg^2 were increased,and the amounts of exchangeable H^ and Al^3 and SO4^2- retained was reduced.The application of ground posphate rock could effctively diminish the pollution of acid rain to soil.  相似文献   

18.
Abstract

Iron (Fe)‐enriched concretions, a complex natural matrix with high chemical heterogeneity and phosphate‐sorption capacity, is widespread in soils with restrictive drainage in Greece. However, the phosphorus (P) status and related characteristics of Fe‐enriched concretions in agricultural soils in areas where P fertilization is mainly inorganic are relatively unknown. Active noncrystalline Fe and aluminum (Al) oxides (Feox, Alox), oxalate extractable P (Pox), P sorption capacity (PSC), and the degree of P saturation (DPS) of Fe‐enriched concretions from agricultural imperfectly drained soils in central Greece were determined using the acid ammonium oxalate method. The concretions contain 13 times as much Feox, twice as much Alox, and almost 15 times as much Pox than the surrounding soil matrix. Pox accounted for 50–80% of total P of the soil concretions, indicating strong accumulation of noncrystalline P components (Al‐ and Fe‐P). The PSC, expressed as a 0.5 (Alox+Feox), ranged from 184.7 to 314 mmol kg?1, demonstrating the strong affinity of the Fe‐enriched concretions for P. The DPS, which represents the fraction of concretion sorbent surface coverage by P, was computed as 100 (Pox/PSC) with values ranging from 6 to 13% (mean=8%). The results of this study indicate that the Fe‐enriched concretions, due to their high noncrystalline Fe and Al oxides content, act as major sink of phosphate, controlling the location, mobility, and dynamics of P in agricultural soils with restrictive drainage.  相似文献   

19.
通过对昆明西山山原红壤和红色石灰土的pH值和磁化率测试研究发现,山原红壤的pH值在4.0～5.8之间,呈酸性,质量磁化率在56 × 10-8～ 174× 10-8 m3/kg之间,pH值与磁化率呈明显的正相关关系;而红色石灰土pH值在6.0～8.4之间,磁化率为752× 10-8 ～5056×10-8m3/kg,pH值和磁化率呈负相关关系.该研究表明,在我国西南地区,土壤pH值和磁化率既存在明显的负相关关系也存在正相关关系.结合前人在其他地区的研究资料,进一步发现,土壤的酸碱环境可能是决定这些关系的重要因素.  相似文献   

20.
《土壤圈》1996,6(3):255-263
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