Changes in carbon pool and CO<Subscript>2</Subscript> emission in the course of postagrogenic succession on gray soils (Luvic Phaeozems) in European Russia

An analogous time series of fallow ecosystems (gray soils (Luvic Phaeozems) plowed and fallowed for 2, 7, 20, 60, and more than 120 years) in the broad-leaved forest zone of Orel oblast has been analyzed. Changes in carbon pool and CO2 emission in the course of postagrogenic succession during the vegetation and winter seasons have been estimated. The restoration of ecosystems on Luvic Phaeozems follows regularities revealed in analogous studies of southern taiga Podzols and forest-steppe Chernozems. Analogously to the other studied zonal chronosequences, total annual soil respiration on Luvic Phaeozems reaches the initial level of undisturbed ecosystems simultaneously with the restoration of phytomass reserve, although significantly earlier than the organic carbon reserve in soils is restored. According to regression models, among the zonal fallows in European Russia, including the southern taiga (Podzols), mixed forests (Luvisols), broadleaved forests (Luvic Phaeozems ), forest-steppe (Chernozems) and dry steppe (Calcisol–Solonetz soil complexes), the mean annual soil respiration is maximum in the zone of gray soils and Chernozems. The increase in soil respiration under artificial wetting (Birch effect) on fallows in the broad-leaved forest zone is minimum among the studied zonal chronosequences: 1.1 ± 0.6 (no effect), which corresponds to the optimal hydrothermal conditions in this zone.     

Micromorphology and Late Glacial/Holocene genesis of Luvisols in Mecklenburg–Vorpommern (NE-Germany)

In the German soil science literature, Luvisols formed in Weichselian sediments (except from the Early Weichselian) are normally regarded as purely Holocene soils with the main period of development assumed to have been during the Atlantic phase. Although debated at some length since the 1960s, the genesis of the widespread albic Luvisols, with a simplified Ap/Bw/(Eb)/(EBtb)/Btb(g)/C horizon sequence and developed on the flat and slightly undulating till plains of the north German Mecklenburgian Stage (deglaciation 14 000 BP), has yet to be clarified. Periglacial climate during the Late Weichselian led to the formation of sand-filled wedge-shaped structures penetrating Bt horizons. Systematic micromorphologic investigations of soil profiles with sand wedges revealed the occurrence of numerous fragments of rounded limpid clay coatings within periglacial formed lenticular microplates as well as in and at the margins of the sand wedge infillings. Assuming the Younger Dryas as the latest possible phase of formation, the lenticular microplates and the undisturbed sand wedges postdate clay illuviation. Undisrupted clay coatings next to fragmented clay coatings prove a subsequent Holocene clay illuviation. Clay illuviation must have occurred at least in warmer phases of the Late Glacial, together with the already accepted pedogenic processes of decalcification, organic matter accumulation (Ahb horizons), podzolisation and silicate weathering (Bwb horizons) on sites not influenced by groundwater.     

Minerals in the three-component combination of agrochernozems in the Kamennaya Steppe

Properties and mineralogy of fine fractions separated from agrochernozems forming a three-component noncontrasting soil combination in the Kamennaya Steppe have been characterized. The soil cover consists of zooturbated (Haplic Chernozems (Clayic, Aric, Pachic, Calcaric)), migrational-mycelial (Haplic Chernozems (Clayic, Aric, Pachic)), and clay-illuvial (Luvic Chernozems (Clayic, Aric, Pachic)) agrochernozems. All the soils are deeply quasi-gleyed because of periodical groundwater rise. The mineralogy of the fraction <1μm includes irregular mica–smectite interstratifications, di- and trioctahedral hydromicas, imperfect kaolinite, and magnesium–iron chlorite. The profile distribution of these minerals slightly varies depending on the subtype of spot-forming soils. A uniform distribution of clay minerals is observed in zooturbated agrochernozem; a poorly manifested eluvial–illuvial distribution of the smectite phase is observed in the clay-illuvial agrochernozem. The fractions of fine (1–5 μm) and medium (5–10 μm) silt consist of quartz, micas, potassium feldspars, plagioclases, kaolinite, and chlorite. There is no dominant mineral, because the share of each mineral is lower than 35–45%. The silt fractions differ in the quartz-to-mica ratio. The medium silt fraction contains more quartz, and the fine silt fraction contains more micas.     

Quantification of the vertical translocation rate of soil solid-phase material by the magnetic tracer method

Approaches to the quantification of the vertical translocation rate of soil solid-phase material by the magnetic tracer method have been developed; the tracer penetration depth and rate have been determined, as well as the radial distribution of the tracer in chernozems (Chernozems) and dark gray forest soils (Luvisols) of Belgorod oblast under natural steppe and forest vegetation and in arable lands under agricultural use of different durations. It has been found that the penetration depth of spherical magnetic particles (SMPs) during their 150-year-occurrence in soils of a forest plot is 68 cm under forest, 58 cm on a 100-year old plowland, and only 49 cm on a 150-year-old plowland. In the chernozems of the steppe plot, the penetration depth of SMPs exceeds the studied depth of 70 cm both under natural vegetation and on the plowlands. The penetration rates of SMPs deep into the soil vary significantly among the key plots: 0.92–1.32 mm/year on the forest plot and 1.47–1.63 mm/year on the steppe plot, probably because of the more active recent turbation activity of soil animals.     

Genesis of a So-called Ferrolysed Soil of Bangladesh

It was postulated by Brinkman (1970) that low clay contents in the surface horizon of paddy soils (Planosols) are caused by clay destruction through ferrolysis. In an effort to test this, a rice profile from the site of Brinkman's Eutric Planosol (Salna, Bangladesh) and a neighbouring forest soil (Dystric Cambisol) of the same parent material and particle-size distribution (Bhawal National Park) were investigated. The micro-structure, particle-size distribution, mineral contents, pedogenic oxides, contents of Zr, Ti and K of the fine earth and individual fractions and also the exchangeable ions were studied. The clay fraction of both soils were chloritised by interlaying of hydroxy-Al in the smectite interlayers in the surface horizons and got stabilized. As a result CEC showed some decrease. The forest profile has a loose and uniform brown-yellow surface horizon and is relatively rich in coarse sand at 62–75 cm depth which might be caused by a strong termite activity as observed during sampling. On the contrary, the frequent and alternate reducing and oxidizing conditions have resulted in gleying the top soil and forming iron-oxide films on the surface of aggregates during dry periods in the paddy soil. An evaluation of all results shows that a little clay destruction and an enrichment of silt in the top soil through vertisol formation and also through primary parent material stratification were the reasons for low clay content in epipedons. In forest soil there was a little clay migration, while the epipedon of the paddy soil had low clay in addition, because of selective erosion during heavy rains following the destruction of structure by puddling. The ferrolysis as a dominant factor for a clay-low epipedon is improbable, because the clay loss of the neighbouring forest soil can not be explained by ferrolysis.     

Spatial distribution of mineral components in microcombinations of agrogrey soils with the second humus horizon in the Vladimir opolie area

Mineralogical composition of silt and clay fractions (<1.1–5 and 5–10 µm) in heavy loamy agrogrey soils (Luvic Retic Phaeozems) considerably changes both in the vertical (along the soil profile) and horizontal (along soil microcatenas) directions. The eluvial–illuvial distribution pattern of the clay fraction in the podzolized agrogrey soils with the second humus horizon is replaced by the homogeneous distribution in the agrogrey soils with residual carbonates. The distribution of silt fractions in the soil profiles is relatively homogeneous. The clay (<1 µm) fraction of the parent material is represented by the poorly ordered micasmectite interstratifications minerals, the proportion between which changes in the soil profiles in dependence on the particular pedogenetic processes. Hydromicas represent the second important component of the clay fraction. They consist of di- and trioctahedral varieties, the proportion between which changes in the soil profiles. Kaolinite and iron–magnesium chlorite are present in smaller amounts. The second humus horizon is characterized by the lowest content of mica-smectite interstratifications minerals with the high content of smectitic layers and by the lowest content of the clay fraction. Silt fractions are composed of quartz, micas, potassium feldspars, and plagioclases.     

Bildung schlechtkristalliner bis amorpher Verwitterungsprodukte in stark bis extrem versauerten Waldböden

Formation of poorly crystallized weathering products in strongly to extremely acid forest soils Poorly crystallized weathering products, formed as a consequence of wide-spread extrem acidification and silicate weathering in forest soils, were examined using X-ray diffraction (XRD) and fluorescence (XRF), scanning electron microscopy (SEM, EDXRA) and chemical analyses. The investigations were carried out on five extremely acid forest soils (different Luvisols, a Gleyic Luvisol and a Luvic Podzol) derived from different parent materials (loess, sand loess, glacial sands/loam) in Northrhine Westfalia and Schleswig-Holstein. The results reveal an intense destruction of clay minerals and other silicates in the extremely acid topsoils leading to an accumulation of poorly crystallized to amorphous compounds. These weathering products occur predominantly as silicic coatings on the surface of soil aggregates or as small spherical precipitates on mineral surfaces. Besides Si they contain small amounts of Al and Fe.     

Andosol to Luvisol evolution in Central Mexico: timing, mechanisms and environmental setting

Surface and buried Andosols and buried Luvisols of the Nevado de Toluca Late Quaternary tephra-paleosol sequence (Central Mexico) were studied to show whether these soils present an evolutionary sequence and to determine the pedogenic mechanisms and environmental factors involved in the evolutionary process. Micromorphological observations and mineralogical composition of fine sand and clay fractions were used to detect type and succession of soil-forming process. Some of the buried Andosols, defined as “intergrade” Andosols, have a predominantly blocky structure, humus-depleted areas, redoximorphic features and thin clay coatings in Ah horizons. Clay fractions of buried Andosols contain halloysite besides amorphous components, whereas in modern Andosols, allophane is dominant. Luvisols have micro-areas with granular structure and abundant phytoliths in the groundmass of Bt horizons assumed to be the relict Andosol features. Luvisol clay fractions are dominated by halloysite and kaolinite. Primary minerals show micromorphological weathering features in all studied soils being stronger in Luvisols; however, even in Luvisols, sand fractions consist mostly of unstable volcanic silicates. We hypothesise that the studied profiles form an evolutionary sequence: Andosols–“intergrade” Andosols–Luvisols; the soil transformation is supposed to be linked to progressive crystallisation of 1:1 clay minerals. Comparing the Nevado de Toluca paleosol properties with the existing data on volcanic soil climo- and chronesequences and assessing the regional paleopedological and lacustrine records of Quaternary paleoclimates, we concluded that wet/dry climatic oscillations took place during the formation of the studied paleosols. Rapid crystallisation of 1:1 minerals occurred during dry phases, which speeded up the Andosol to Luvisol transformation and made it independent from the primary mineral weathering status. The Andosol to Luvisol transformation accelerated by climatic fluctuations is thought to be a common soil evolutionary pathway in the subtropical and tropical regions of recent volcanism, which suffered contrasting precipitation oscillations in the Quaternary.     

An experience in using the world reference base for soil resources for the soils of western Georgia

New and previously published data on the soils of western Georgia are generalized, and traditional soil names are correlated with the units of the World Reference Base for Soil Resources. It is argued that krasnozems (red ferrallitic soils) can be attributed to the group of Nitisols (the soils characterized by intense weathering (ferralization) and having shiny ped faces in the nitic horizon); yellow and yellow-brown soils (zheltozems), to the group of Luvisols (the soils with relatively high adsorption capacity in the eluvial horizons and with the horizon of the illuvial accumulation of clay); yellow-podzolic (zheltozem-podzolic) soils, to Alisols (slightly acid soils with the low adsorption capacity, poor aggregation of the upper horizons, low-activity (kaolinite) clay, and with the horizon of clay accumulation (argic horizon)); brown forest soils, to Cambisols (the soils with the cambic horizon characterized by some alteration of the lithogenic texture and structure into the pedogenic texture and structure); and mountainous forest-meadow and meadow soils, to Umbrisols (the soils with the dark-colored unsaturated umbric horizon).     

Paleosols in the moraine-mantle loam sequence of northeastern Europe: The memory of pedogenesis rates and evolution of the environment during OIS3

Morpho-analytical features of the paleocatena (a complexly organized heterochronous sequence), which contains 2 pedostratigraphical units: formed on the Holocene mantle loams Umbric Albeluvisol and the underlain Middle Valday (Wűrmian) paleopedocomplex developed on Moscowian (Riss II) moraine deposits, are described. The buried pedocomplex consisted of: 1) the paleohumus and paleogley (2Atgb–2Gtb–3Atgb) and 2) paleohumus (3Atgb–3AtGb) horizons. Thus, these pedostratigraphic units reflect two studies of pedogenesis marked by two paleohumus horizons. The horizons of the paleopedocomplex are separate parts of the profile classified as the Umbric Gley soil formed during OIS3. The ¹⁴C age of the three paleosol horizons varied between 24,350–30,900 yr BP. The studied paleopedocomplex is the only one known containing the Middle-Valday paleosol formed on moraine deposits, which is a clear sign of the northernmost occurrence of the Bryansk fossil soil in Europe. A detailed hierarchical morphological study of the paleopedocomplex, including meso- and submicromorphological and magnetic susceptibility analyses, allowed us to identify the Late Quaternary pedogenic processes under severe extra-continental climate, including gleyzation, aggregation, cracking and humus formation. Good preservation of these individual pedogenic processes is shown to be a soil memory under the overlapping press of Holocene pedogenesis. It was shown that the clay coating in the Middle Valday of the pedocomplex is a part of the Holocene soil formation. Based on the palynological data, it is possible to subdivide the development of paleovegetation of the area into four stages during which the paleosol horizons had being formed. At the beginning and the final stage of the Middle Valday, the forest–tundra landscapes with inclusions of tundra–steppe associations predominated. During the optimum of Bryansk Interstade, the periglacial pine-birch formations were widespread.     

Temporal changes of eroded soils depending on their agricultural use in the southern Cis-Ural region

Temporal changes of eroded soils in the southern Cis-Ural region (Republic of Bashkortostan) depending on their agricultural use during the period from 1975 to 2011 were studied. In the northern foreststeppe zone, the development of erosion processes was retarded upon the use of soil-saving management practices and grain-fallow-grass crop rotations. In slightly eroded light gray forest soils (Eutric Retisols (Cutanic)), the thickness of humus-accumulative horizons and the content of humus increased; the conversion of cropland into permanent fallow was found to be the most efficient measure to control soil erosion. In podzolized chernozems (Luvic Greyzemic Chernic Phaeozems) and typical chernozems (Haplic Chernozems) of the Cis-Ural steppe, the content of humus in the plow layer under grain-row crop rotation and classical soil management decreased, especially in moderately eroded soils. The development of water and wind erosion on slopes depended on the slope shape: the texture of soils at different degrees of erosion on slopes with free runoff became coarser by one gradation after 35 years; in the presence of linear obstacles in the lower part of slopes, the content of fine fractions in moderately and strongly eroded soils increased.     

Physical properties of tsunami-affected soils in Aceh, Indonesia: 2½ years after the tsunami

On 26 December 2004, a tsunami caused extensive loss of life, damaged property and degraded agricultural land in the province of Aceh, Indonesia. While some of the associated soil chemical changes have been documented, information on soil physical properties is sparse. The objective of this study was to quantify physical properties of some tsunami-affected upland agricultural soils in Aceh, Indonesia. Soil was sampled approximately 21/2 years after the tsunami, from the 0–0.1 m, 0.1–0.3 m and 0.3–0.5 m depths in four sites in the villages of Kling Cot Aroun in Aceh Besar sub-district, Kuta Kruen in Aceh Utara sub-district, Udjong Blang Mesjid in Bireuen sub-district and Meue in Pidie Jaya sub-district on the east coast of Aceh. These sites were located within 1 km from the sea at elevations ranging from 0 to 5 m ASL. The soils were Ultisols except for Meue, which was an Entisol. Soil properties measured were bulk density, structural stability and particle size distribution. Soil water retention, pore-size distribution and saturated hydraulic conductivity were estimated by inserting the values of bulk density, clay, sand and silt contents into pedotransfer functions from the literature. The analyses conducted during this study did not permit us to ascertain what proportion of the soil particles were of tsunami-origin. Nonetheless, deposition of finer-textured material may have occurred in two of the sites. In comparison with the greyish-white, coarse textured soil in the rest of the profile, a finer-textured yellow horizon was present in the lower slopes of the Udjong Blang Mesjid site. At Meue, clay and silt contents were higher in the surface 0.3 m than in the 0.3–0.5 m depth, although a distinct horizon was absent. Particle size distribution in all sites was dominated by the sand fraction, although clay and silt contents were relatively high (20–30 g 100 g^− 1) at Kuta Kruen. Among the sand fractions, fine sand (0.02–0.25 mm) was highest at Kling Cot Aroun, Kuta Kruen and in the “yellow horizon” at Udjong Blang Mesjid, making them more prone to hardsetting and compaction after intensive tillage. Soil compaction was present in all sites with that in the “yellow horizon” at Udjong Blang Mesjid being highest. The relatively low porosity in this layer may be beneficial, as it is likely to reduce the high rates of water drainage and nutrient leaching in this sandy soil. The more compacted soils were characterised by higher numbers of micropores (r, pore radius < 4.3 μm), lower water retention at saturation, smaller numbers of macropores (r > 14.3 μm), lower hydraulic conductivity and intensive gleying, indicating frequent waterlogging. The soils in all depths from Kling Cot Aroun and the “yellow horizon” at Udjong Blang Mesjid were very dispersive, that at Meue moderately dispersive in the 0.3–0.5 m depth but stable in the 0–0.1 m depth, and at Kuta Kruen very stable in all depths. Soil physical degradation was a feature of the soils examined, and its amelioration will be the key to improving and sustaining crop yields in these soils. Possible management interventions include organic amendments such as compost or manure, and minimum tillage options such permanent beds or zero tillage with retention of crop residues as in situ mulch together with suitable cover crops.     

Properties,degradation risks and rehabilitation possibilities of heavy soils in Bulgaria

The objective of this study was to determine soil properties, limiting site deficiencies for agricultural production and degradation risks of some major soil groups of Bulgaria. Vertisols, Planosols, Chernozems and Luvisols were characterised based on soil analyses. Temporal waterlogging in combination with water erosion, soil compaction and chemical degradation limit the fertility of Vertisols and Planosols. Chernozems and Luvisols are partly compacted. To ensure soil productivity for coining generations and to protect soil and water resources, the evident soil degradation must be halted. Long‐term field studies of soil rehabilitation variants were conducted. Soil parameters and crop yield were the main indicators used to estimate soil quality. Pipe drainage in combination with subsoiling and the application of gypsum and limestone, respectively, are effective measures for site rehabilitation of degraded Vertisols and Planosols. Degraded Luvisols and Chernozems characterised by distinct and persistent subsoil compaction can be regenerated by subsoil loosening and following site‐adapted soil management practices.     

Changes in the Properties of Crimean Haplic Chernozems under the Impact of Forest Plantations

Eurasian Soil Science - The impact of 50-year-old forest plantations on the properties of postagrogenic segregational chernozems (postagrogenic Haplic Chernozems) in the steppe Crimea has been...     

Total and carboxyl acidity and methoxyl groups of humic acid preparations of chernozemic soils

Abstract

Alkaline‐soluble, acid‐precipitable organic matter from the Ah and Bm horizons of Chernozemic soils developed on four parent materials in each of three soil zones was analyzed for total and carboxyl acidity, and methoxyl groups. The values are expressed as meq/g dry ash‐free organic matter.

Total acidity generally was higher in the Black Chernozems than in the Brown Chernozems and higher in the Bm horizon than in the Ah horizon. The distribution of carboxyl acidity between the Ah and companion Bm horizons of individual soils appeared to be related to texture and rainfall.

The. methoxyl group content of the Brown Chernozems was larger than that of the .Dark Brown Chernozems, which in turn had a larger methoxyl group content than that of the Black Chernozems. It was concluded that the organic matter in the Ah horizons of the Brown Chernozems was not as humified as that of the Black Chernozems. The pH value and a minimum clay content are possible determining factors as to the amounts of methoxyl carbon present.     

Specific Features of Profile Distribution and Crystallochemistry of Phyllosilicates in Soils of the Cisbaikal Forest-Steppe

The mineralogical composition of agrogray, dark gray, and agro-dark gray soils (Luvic Greyzemic Retic Phaeozems); agro-dark gray residual-calcareous soils (Calcaric Cambic Phaeozems); clay-illuvial agrochernozems (Luvic Chernic Phaeozems); and agrochernozems with migrational–mycelial carbonates (Haplic Chernozems) developed in the forest-steppe of Central Siberia within the Irkutsk Depression has been studied. The clay (<1 μm) fraction separated from these soils consists of mixed-layer minerals with alternating layers of hydromica, smectite, vermiculite, and chlorite; the proportions between them change within the soil profiles. The clay fraction also contains hydromicas, kaolinite, chlorite, and some admixture of the fine-dispersed quartz. Each type of the soils is characterized by its own distribution pattern of clay material with specific alternation of layers in the mixed-layer formations. Mixed-layer minerals of the chlorite–vermiculite type predominate in the upper horizons of texture-differentiated soils. Down the soil profile, the content of mixed-layer mica–smectitic minerals increases. In the clay fraction of arable dark gray-humus soils with residual carbonates, the distribution of the clay fraction and major mineral phases in the soil profile is relatively even. An increased content of well-crystallized kaolinite is typical of these soils. The parent material of agrochernozems has a layered character: the upper horizons are generally depleted of clay, and the middle-profile and lower horizons are characterized by the considerable kaolinite content. In general, the clay material of soils of the Tulun–Irkutsk forest-steppe differs considerably from the clay material of foreststeppe soils developed from loesslike and mantle loams in the European part of Russia. In particular, this difference is seen in the proportions between major mineral phases and between biotitic and muscovitic components, as well as in the degree of crystallinity and behavior of kaolinite and chlorite.     

Dynamics of the agrochemical fertility parameters of arable soils in the southwestern region of Central Chernozemic zone of Russia

Data of the agrochemical survey of arable soils in Belgorod oblast during the period from 1964 to 2014 have been analyzed. The soil cover mainly consists of typical chernozems (Haplic Chernozems) and leached chernozems (Luvic Chernozems) in the forest-steppe zone and ordinary chernozems (Calcic Chernozems) in the steppe zone. Under long-term agricultural use (from 1964 to 2014), the content of mobile phosphorus in arable soils of the region under study has increased from 55 to 137 mg/kg, and the content of mobile potassium has increased from 105 to 147 mg/kg. During the period of 1976–2014, the share of acid soils has increased from 22.8 to 45.8%, including medium-acid soils from 1.5 to 12.6%. No significant changes in the weighted average content of soil organic matter are revealed for the period from 1985 to 2014. The value of this parameter is within the range of 4.8–5.0%. In the 2010–2014, 95.0% of arable soils belonged to the category of low supplied with mobile sulfur; 99.2, 96.9, 94.1, and 54.4% of soils were poorly supplied with zinc, copper, cobalt, and manganese, respectively. During the same period, the maximum average productivity of the crop area (3710 f. u./ha) was noted at the application of 4.8 t/ha organic fertilizers and 97.9 kg/ha organic fertilizers on the average. The maximum long-term yields of sugar beet (36.8 t/ha) and corn grain (4.97 t/ha) were obtained at the application of relatively low fertilizer rates.     

草原土壤：分布、分类与演化

草原土壤系指草原、湿草原和森林草原植被下形成的富含有机质、盐基饱和度高的暗色土壤.世界上此类土壤面积约900万km2,我国约76万km2,是粮食生产的重要基地.本文比较了国际上草原土壤分类.不论俄罗斯或中国,均腐土开垦以后土壤有机质开始下降迅速,而后减缓,逐步达到与当地生物气候相适应的水平.所以至今仍保持一定厚度的黑土层.在均腐土资源的利用和保护上,一方面应保持其有机质平衡,另一方面更重要的是严防水土流失,以保证其生产能力.     

Estimation of soil weathering stage and acid neutralizing capacity in a toposequence Luvisol–Cambisol on loess under deciduous forest in Belgium

Soils derived from loess are extensive in Europe and are well suited for forestry. They are suspected to be poor acid buffers, however. We have estimated the weathering stage and acid neutralizing capacity of acid soils under forest in a toposequence on loess in the Belgian silt belt. The soils vary distinctly in morphology and physico‐chemical properties according to their topographic position. Dystric Cambisols have developed in colluvial deposits in the dry valley floors, whereas Dystric Luvisols have formed on the slopes in a rejuvenated material. The Cambisols are more acid and less saturated in bases than are Luvisols. They are strongly depleted of clay and contain less weatherable minerals. Easily weatherable minerals are concentrated mainly in the clay fraction of both soil types. Clay minerals of size < 2 μm therefore act as major sinks for protons in these soils. A simplified expression taking into account the total reserve in bases, total aluminium and iron occluded in silicates is used to estimate acid neutralizing capacity. Our estimates confirm that these acid loessic soils are indeed poor acid buffers. They show that the Dystric Cambisols depleted of clay are sensitive to potential acidification, whether natural or man‐made.     

The influence of long-term cultivation on soil properties and patterns in an undulating terrain in Poland

Soil utilization has, for many years, strongly influenced the properties of soils in the undulating terrain of the Lublin Upland. Population increase and suitability of the soils (particularly Luvisols, Cambisols and Chernozems derived from loess and loess-like formations) for arable agriculture were the main reasons for deforestation. This led to erosion, which caused changes in soil morphology and the development of a mosaic soil cover. Accelerated erosion was strongest on slopes exceeding 18%. It resulted in selective loss of clay. The main changes in silty soils developed from loess and loess-like deposits occurred in the first few decades after cultivation started. They included a decrease in organic matter content from an average of 2.3% organic C in the forest soils to about 1% in the arable soils. No further changes in humus content were observed, but the proportion of fulvic acids increased at the expense of humic acids. The pH_KCl rate decreased at the slope foot from about 5.8 to 5.0. Morphological changes in rendzinas were much lower than in the soils derived from loess. We do not expect big changes in these soils in the next 100 years if their use remains the same.