Study of Pedo Genesis of soils of Bundi district (Rajasthan)

The soils of Rajasthan vary from desert sand to heavy clay with all intermediate stages like sandy loam, loam and clay loam. The last two textural groups are more prevalant on the eastern, northeastern and southeastern part of the Aravallies which run almost in the middle of the State from southeast to northeast. The latter groups of soils have more potential from the point of agricultural development in the State. These soils are widely termed as alluvial soils which is a general term to indicate the nontaxonomic group of soils that have parent material of alluvial origin, Riecken ¹⁷, Kelloog ⁸ has referred to the soils developed from the alluvium as classified under variety of world soil groups. In our country many of the alluvial soils have not yet been studied from the soil genesis point of view as a measure to classify the soils under taxonomic groups. Ray Chawdhary and Mukerji ¹⁵, concluded that the alluvial soil groups of our country are ill defined and the classification of these soils need more study. Basu ³ was able to distinguish the genetic characteristics of the soils of Deccan. Agrawal and Mukherji ¹⁾ established that distinct genetic soil types have come into expression under Gangetic alluvium. Agarwal ² has concluded about the three types of soils in the toposequence with precipitated calcium throughout, zone of calcium accumulation in the bottom of the profile and soils free of calcium, and suggests that the soils of Gangetic plain be called as derived from alluvium. A process of reclassifying the alluvial soil series into taxonomic groups is a common trend in the United States since the last two decades.     

Inclusion of soils and soil-like bodies of urban territories into the Russian soil classification system

The results of the Internet discussion on the classification of urban soils aimed at evaluating their possible inclusion into the modern Russian soil classification system adopted by a wide range of specialists are presented. The first step was to address the urban diagnostic horizons as the basis for identifying soil types according to the rules of the Russian soil classification. New diagnostic horizons were proposed for urban soils: urbic (UR), filled compost-mineral (RAT), and filled peat (RT). The combination of these horizons with other diagnostic horizons and layers of technogenic materials correspond to different soil types. At the subtype level, the diagnostic properties (qualifiers) that may reflect both natural phenomena (gley, alkalinity) and technogenic impacts on the soils (urbistratified; phosphatic; or poorly expressed urban—ur, rat, rt) are used. Some corrections were proposed for the system of parent materials in urban environments. Urban soils formerly described in another nomenclature—urbanozems, urbiquasizems, and culturozems—are correlated with the taxa in all the trunks of the system. The proposals accepted can be used for the next updated version of the new Russian soil classification system.     

Correction of a large-scale soil map with the use of the new classification system of Russian soils

A large-scale soil map of one of the farms in the south of Karelia has been analyzed. This map was initially compiled in 1979 on the basis of the official Classification and Diagnostics of Soils of the Soviet Union (1977). We have corrected it with the use of the new Classification and Diagnostics of Russian Soils. Both the names of the map units and the particular delineations on the map have been changed. These changes are related to differences in the principles of soil diagnostics in the old and new classification systems and to real changes in the soil cover that have taken place after the map’s compilation. In particular, large areas of peat bogs have been drained, and the cultivated peat soils have been subjected to accelerated mineralization. Surface planing works after digging drainage channels have also changed the soil cover pattern. The revised large-scale soil map developed on the basis of the new classification system gives more adequate information about the real soil cover.     

Long-term dynamics of the anthropogenic salinization of soils in Moscow (by the example of the Eastern district)

The long-term (1989–2010) and seasonal dynamics of the anthropogenic salinization of soils related to the use of deicing mixtures in the Eastern Administrative District of Moscow were examined. Data on the chemical composition of deicing mixtures and on the contents of soluble salts in the snowmelt and in the soil profiles of different functional zones were analyzed. The maps of soil salinization were compiled for 1989, 2005, and 2010; on their basis, the resulting map of the degree of soil degradation was developed. The areas with abnormal concentration of salts in the soils expanded during the study period (21 yrs), and the average content of salts in such areas increased by 3.2 times. The maximum total content of salts was found in the spring season in the soils along major highways.     

A tentative proposal for productivity classification of paddy soils in a detailed soil survey

In Japan, half of the total crop yield consists of rice grown in paddy fields as the nation's staple food. In the past ten years, serious consideration has been given to the stagnant production of rice, at a rate of about 450 kg unhulled rice to ten ares.     

Ecology of soil springtails (Collembola, Insecta) from pine woods and Rhododendron shrublands in the Central and Eastern Pyrenees (North Spain)

The collembological composition of samples from the Central and Western Pyrenees (Northern Spain) was studied. Soils from two biotopes (pine forest and Rhododendron shrub) were studied in Nuria and Vallibierna, using different diversity indices and multivariate analyses. Ten species were found that were endemic to the Iberian Peninsula. Three of these are exclusive to the Pyrenees: Ceratophysella elegans, Hypogastrura dasiensis and Protachorutes pyrenaeus. The greatest diversity was observed in the soils of Rhododendron, above all at Nuria. Collembola were most poorly represented in the pine forest of Vallibierna, where the endemic Hypogastrura meridionalis was the dominant species. Multivariate analyses indicated that the latter species characterizes this pine forest and separates it from all other biotopes studied. The evenness (E) was most pronounced in Nuria, where Folsomia manolachei was the characteristic species.     

Holocene paleosols and colluvial sediments in Northeast Tibet (Qinghai Province,China): Properties,dating and paleoenvironmental implications

Colluvial deposits consisting of silts and loams were detected in several climatologically different areas of NE Tibet (3200–3700 m a.s.l.). Layering, distinct organic content and low content of coarse matter as well as location in the relief revealed an origin from low-energy slope erosion (hillwash). Underlying and intercalated paleosols were classified as Chernozems, Phaeozems, Regosols and Fluvisols. Fifteen radiocarbon datings predominant on charcoal from both colluvial layers and paleosols yielded ages between 8988 ± 66 and 3512 ± 56 uncal BP. Natural or anthropogenic factors could have been the triggers of the erosional processes derived. It remains unclear which reason was mainly responsible, due to controversial paleoclimatic and geomorphic records as well as insufficient archaeological knowledge from this region. Determinations of charcoal and fossil wood revealed the Holocene occurrence of tree species (spruce, juniper) for areas which nowadays have no trees or only few forest islands. Thus large areas of NE Tibet which are at present steppes and alpine pastures were forested in the past.     

Kinetic behavior of Fe(o,o-EDDHA)-humic substance mixtures in several soil components and in calcareous soils

Ferric ethylenediamine- N, N'-bis-(o-hydroxyphenylacetic)acid chelate (Fe(o, o-EDDHA)) is one of the most effective Fe fertilizers in calcareous soils. However, humic substances are occasionally combined with iron chelates in drip irrigation systems in order to lower costs. The reactivity of iron chelate-humic substance mixtures in several soil components and in calcareous soils was investigated through interaction tests, and their behavior was compared to the application of iron chelates and humic substances separately. Two commercial humic substances and two Fe(o, o-EDDHA) chelates (one synthesized in the laboratory and one commercial) were used to prepare iron chelate-humic substance mixtures at 50% (w/w). Various soil components (calcium carbonate, gibbsite, amorphous iron oxide, hematite, tenorite, zincite, amorphous Mn oxide, and peat) and three calcareous soils were shaken for 15 days with the mixtures and with iron chelate and humic substance solutions. The kinetic behavior of Fe(o, o-EDDHA) and Fe non-(o,o-EDDHA) (Fe bonded to (o,p-EDDHA) and other polycondensated ligands) and of the different nutrients solubilized after the interaction assay was determined. The results showed that the mixtures did not significantly reduce the retention of Fe(o, o-EDDHA) and Fe non-(o,o-EDDHA) in the soil components and the calcareous soils compared to the iron chelate solutions, but they did produce changes in the retention rate. Moreover, the competition between humic substances and synthetic chelating agents for complexing metal cations limited the effectiveness of the mixtures to mobilize nutrients from the substrates. The presence of Fe(o, p-EDDHA) and other byproducts in the commercial iron chelate had an important effect on the evolution of Fe(o, o-EDDHA) and the nutrient solubilization process.     

Nitrogen-fixing microorganisms in paddy soils (Part 2) distribution of blue-green algae in paddy soils and the relationship between the growth of them and soil properties

As was shown in the previous report^l), a close connection between the photosynthetic autotrophs and nitrogen fixation in paddy soils was demonstrated.     

Characteristics and classification of anthropogenic soils in the Osnabrück area,Germany

Soils in the area around Osnabrück/Northwest Germany have been strongly influenced by man. The classification of these soils based on the German and international classification systems is problematical. Eight representative soils, two Anthrosols (plaggic and hortic), four soils affected by the coal and steel industry and consisting of distinct monosubstrata (coal and ore mining heaps, slag heap, sludge area) as well as two deposits of heterogeneous waste components (reclaimed wet land, filled quarry) were investigated. The sites are assessed in relation to their contamination by heavy metals and PAH as well as suitability for plant growth. An attempt was made to classify the soils using the current classification of World Reference Base for Soil Resources (WRB), German Soil Science Society Classification, FAO and the USA. These systems enables a satisfactory classification of two Anthrosols compared with the other soils. In the US taxonomy, the pedogenesis of technological substrata was not considered. In the FAO taxonomy, it is not acceptable to term all soils as Urbic Anthrosols without any further differentiation. This differentiation was enabled in both the WRB and the German taxonomy. In the WRB taxonomy, however, only anthropic subunits of the Regosols are included. An improvement could be achieved by the introduction of comparable subunits of the Arenosols, Durisols, Gleysols, and Leptosols. In the German taxonomy (normally soil and substrata are classified separately), the induction of toxic subunits in the presence of high soil contamination influencing the edaphon would be helpful. Furthermore, soils hardened by silica should be classified as respective varieties.     

On the value of soil columns for assessing the transport pattern of viruses through soils: A critical outlook

The U.S. Water Pollution Control Act Amendment of 1972 (PL 92-500) has made land disposal of wastewater effluents and residuals a viable and attractive alternative (Thabaraj, 1975; Wright, 1975). Land spreading of wastewater effluents and residuals has many advantages, inclding the addition of plant nutrients, water conservation, improvement of soil physical properties, and increased soil organic matter. Public health risks associated with land disposal of wastes containing human pathogens can be assessed only through a thorough examination of the survival and transport pattern of these pathogens through soils. This topic has been thoroughly covered in recent reviews (Bitton, 1975, 1979; Burge and March, 1978; Foster and Engelbrecht, 1973; Gerbaet al., 1975) and need not be examined any further. In this review, we are primarily concerned with a critical examination of the various methods frequently used to assess soils' potential to retain viruses. Knowledge concerning the transport pattern of viruses through soils can be gained through field monitoring of these infectious particles in wastewater effluents, sludges, soils and groundwater, and/or through soil column experiments. The latter have been criticized and our purpose is to examine these criticisms and suggest, if necessary, some alternate solutions. Furthermore, we will review the practical information gained through soil column studies and examine, with the aid of examples of land application sites across the country, the relationship between laboratory and field studies.     

Characteristics,classification, and agricultural potential of some Niger delta soils in Nigeria

Abstract

Nine pedons representing the major soils of an 80,000 ha area in Yenagoa, Niger Delta, Nigeria, were classified and evaluated for maize, plantain and oil palm cultivation. The soils were identified as low activity clay (LAC) Ultisols (Kanhapludult and Kandiudult) or Acrisols (FAO, UNESCO) with hydromorphism reaching the A‐horizon in most cases. They were mainly derived from alluvial materials. The presence of an argillic B‐horizon in all the pedons indicated that the depositions were not recent. Most of the soils were sandy at he top but clayey in the subsoils although a few have either sandy or clayey texture throughout the profile. Organic matter content in the A‐horizon was 2.30–4.50%. The pH was between strongly acidic (3.5) to slightly acidic (5.0). The CEC in the B‐horizon was low (<24 cmol kg^‐1) in the sandy soils and moderate (>24 cmol kg^‐1) in the clayey soils. The exchange complex was dominated by Ca (2–17 cmol kg^‐1), followed by Mg (1–8 cmol kg^‐1), while K was low (0.07–0.22 cmol kg^‐1) to fairly high (>0.66 cmol kg^‐1). The base saturation was just moderate (50–92%). The soils were marginally suitable (S3) for maize, with about 20% of the area not suitable (N1) presently. The main constraints to arable cultivation were heavy rainfall, imperfect or poor drainage, and low base saturation. They are moderately suitable (S2) for plantain due to low base saturation, short dry season, and unfavorable texture which was light in some and too heavy in others. For oil palm, the soils were moderately (S2) to highly (S1) suitable, though the short dry season, low base saturation and poor drainage could pose as limitations. Obviously, with good drainage and proper fertility management high yields of maize, plantain and oil palm could be obtained on these soils. Such studies should be made to cover the entire Niger Delta in order to provide data to justify the preservation of all prime agricultural soils in the area from being lost to the oil industry.     

Characterization of soil physico-chemical parameters and limitations for revegetation in serpentine quarry soils (NW Spain)

Purpose

Quarrying activities in areas with serpentinized rocks may have a negative impact on plant growth. Quarry soils generally offer hostile environments for plant growth due to their low-nutrient availability, low organic matter, and high-trace metal content.

Materials and methods

In order to determine the factors that can limit plant revegetation, this study was carried out in two serpentine quarries in Galicia (NW Spain): one abandoned in 1999 and the other still active.

Results and discussion

The results show that in soils developed in the abandoned quarry, the limitations for revegetation were: moderate alkaline pH (7.87–8.05), strong Ca/Mg (<1) imbalance, low N (<0.42 mg kg^?1) and P (<2 mg kg^?1) content, and high total heavy-metal content (Co 76–147 mg kg^?1; Cr 1370–2600 mg kg^?1; and Ni 1340–2040 mg kg^?1). The limitations were much less intense in the soils developed in the substratum in the active quarry, which were incipient soils poorly developed and permanently affected by the quarrying activity.

Conclusions

Restoration work should be geared toward establishing a stable diverse vegetation cover, including serpentinophile species, which would provide the necessary modifications to correct nutritive imbalances and improve soil quality.

     

Guideline for the description of soils in the Berlin metropolitan area: an extension for surveying and mapping anthropogenic and natural soils in urban environments within the German soil classification system

Journal of Soils and Sediments - In urban areas, humans shape the surface, (re-)deposit natural or technogenic material, and thus become the dominant soil formation factor. The 2015 edition of the...     

丘陵山区水土治理的核心是"三集"

回顾总结历史的经验教训，丘陵山区水土治理的核心是变跑水、跑肥、跑土为集水、集肥、集土，简称变“三跑”为“三集”。“三集”的关键是蓄水，要因地制宜，因害设防，工程、生物、耕作三大水土保持措施合理配置。提出了不同类型“三集”田的建设模式与实施措施。     

Radioactivity of the granitic soils in the middle district of tottori prefecture

The greater part of the middle district of Tottori Prefecture is formed of biotite granite, hornblende andesite, augite andesite and hornblende andesitic volcanic detritus. The granite occurs in the region streching to the north-east from the border between both Tottori and Okayama Prefecture. In this granite area, there can be seen many dikes of aplite and micropegmatite. These granitic rocks, and the soils derived from them have higher radioactivity than other rocks and soils. In this district, there are radioactive hot springs-Sekigane, Misasa, Shikano and Hamamura, and, recently uranium ore was found at Ogamo and Ningyotoge. A study was made on the radioactivity of the soils derived from the granitic rocks, andesite and tertiary shale, of the ashes from plants grown on these soils, and on the extraction of thorium X in the soils.