Systematic Soil Survey Research Articles

Geostatistical assessment and mapping of soil spatial variability in Sirumugai, Western Ghats

This study examines the spatial variability of soil properties and classifies the soil in the Sirumugai Reserved Forest range, located in the Western Ghats, India. A systematic soil survey and profile studies were conducted, using landforms as the basis for investigation within the study area. Horizon-wise soil samples were analysed for key soil parameters, including pH, electrical conductivity (EC), soil organic carbon, phosphorus, and potassium. The results revealed significant variations in soil properties across different locations, primarily influenced by elevation. The coefficient of variation for phosphorus was 0.87, while for potassium, it was 0.48. The analysis also encompassed assessments of skewness and kurtosis. pH (0.15) and phosphorus (0.75) exhibited kurtosis values close to 1, indicating relatively normal and flatter distributions. Conversely, sodium (27.10), elevation (3.91), and calcium demonstrated high kurtosis. Most soil properties were found to be right-skewed, while bulk density (0.09) was left-skewed. Geostatistical analysis in the Sirumugai Reserved Forest revealed considerable spatial variability in soil properties, particularly in EC and organic carbon. Elevation emerged as a strong influencing factor for soil properties, coupled with soil depth and nutrient leaching, which were prominent at higher altitudes. Ordinary kriging provided accurate spatial predictions, offering valuable insights for land management and conservation strategies tailored to the region.

Distinct latitudinal patterns and drivers of topsoil nitrogen and phosphorus across urban forests in eastern China.

Nitrogen (N) and phosphorus (P) are the two most important macronutrients supporting forest growth. Unprecedented urbanization has created growing areas of urban forests that provide key ecosystem services for city dwellers. However, the large-scale patterns of soil N and P content remain poorly understood in urban forests. Based on a systematic soil survey in urban forests from nine large cities across eastern China, we examined the spatial patterns and key drivers of topsoil (0-20 cm) total N content, total P content, and N:P ratio. Topsoil total N content was found to change significantly with latitude in the form of an inverted parabolic curve, while total P content showed an opposite latitudinal pattern. Variance partition analysis indicated that regional-scale patterns of topsoil total N and P contents were dominated by climatic drivers and partially regulated by time and pedogenic drivers. Conditional regression analyses showed a significant increase in topsoil total N content with lower mean annual temperature (MAT) and higher mean annual precipitation (MAP), while topsoil total P content decreased significantly with higher MAP. Topsoil total N content also increased significantly with the age of urban park and varied with pre-urban soil type, while no such effects were found for topsoil total P content. Moreover, topsoil N:P ratio showed a latitudinal pattern similar to that of topsoil total N content and also increased significantly with lower MAT and higher MAP. Our findings demonstrate distinct latitudinal trends of topsoil N and P contents and highlight a dominant role of climatic drivers in shaping the large-scale patterns of topsoil nutrients in urban forests.

Harmonisation of a large-scale historical database with the actual Czech soil classification system

The possibility of the adequate use of data and maps from historical soil surveys depends, to a large measure, on their harmonisation. Legacy data originating from a large-scale national mapping campaign, “Systematic soil survey of agricultural soils in Czechoslovakia (SSS, 1961–1971)”, were harmonised and converted according to the actual system of soil classification and descriptions used in Czechia – the Czech taxonomic soil classification system (CTSCS). Applying the methods of taxonomic distance and quantitative analysis and reclassification of the selected soil properties, the conversion of two types of mapping soil units with different detailed soil information (General soil representative (GSR), and Basic soil representative (BSR)) to their counterparts in the CTSCS has been effectuated. The results proved the good potential of the used methods for the soil data harmonisation. The closeness of the concepts of the two classifications was shown when a number of soil classes had only one counterpart with a very low taxonomic distance. On the contrary, soils with variable soil properties were approximating several related units. The additional information on the soil skeleton content, texture, depth and parent material, available for the BSR units, showed the potential in the specification of some units, though the harmonisation of the soil texture turned out to problematic due to the different categorisation of soil particles. The validation of the results in the study region showed a good overall accuracy (75% for GSR, 76.1% for BSR) for both spatial soil units, when better performance has been observed in BSR. The conversion accuracy differed significantly in the individual soil units, and ranged from almost 100% in Fluvizems to 0% in Anthropozems. The extreme cases of a complete mis-classification can be attributed to inconsistencies originating in the historical database and maps. The study showed the potential of modern quantitative methods in the legacy data harmonisation and also the necessity of a critical approach to historical databases and maps.

Preprocessing procedures and supervised classification applied to a database of systematic soil survey

ABSTRACT: Data Mining techniques play an important role in the prediction of soil spatial distribution in systematic soil surveying, though existing methodologies still lack standardization and a full understanding of their capabilities. The aim of this work was to evaluate the performance of preprocessing procedures and supervised classification approaches for predicting map units from 1:100,000-scale conventional semi-detailed soil surveys. Sheets of the Brazilian National Cartographic System on the 1:50,000 scale, “Dois Corregos” (“Brotas” 1:100,000-scale sheet), “Sao Pedro” and “Laras” (“Piracicaba” 1:100,000-scale sheet) were used for developing models. Soil map information and predictive environmental covariates for the dataset were obtained from the semi-detailed soil survey of the state of Sao Paulo, from the Brazilian Institute of Geography and Statistics (IBGE) 1:50,000-scale topographic sheets and from the 1:750,000-scale geological map of the state of Sao Paulo. The target variable was a soil map unit of four types: local “soil unit” name and soil class at three hierarchical levels of the Brazilian System of Soil Classification (SiBCS). Different data preprocessing treatments and four algorithms all having different approaches were also tested. Results showed that composite soil map units were not adequate for the machine learning process. Class balance did not contribute to improving the performance of classifiers. Accuracy values of 78 % and a Kappa index of 0.67 were obtained after preprocessing procedures with Random Forest, the algorithm that performed best. Information from conventional map units of semi-detailed (4th order) 1:100,000 soil survey generated models with values for accuracy, precision, sensitivity, specificity and Kappa indexes that support their use in programs for systematic soil surveying.

Effects of different land-use managements on soil fertility status in Rift Valley Areas of Gamo-Konso Massifs, Ethiopia

Understanding soil properties and their productiveness under different land use management have proved to be useful for sustainable development and efficient utilization of limited land resources. A systematic soil survey was made for the first time in the Ethiopian Rift valley flat plain areas of Gamo-Konso Massifs. The objectives were to: (1) identify the land uses and their role on soil physicochemical properties under varying climatic conditions; (2) assess the nature and extent of soil salinity problems; (3) identify best land use management practices. Annual crops (AA); perennial crops (AP), and Natural Forest (NF) land-uses were identified. The result showed organic carbon (OC) and total nitrogen (TN) were varied along different land uses. Generally, OC, TN, percentage base saturation, exchangeable (potassium, calcium and magnesium), available, phosphorus (P 2 O 5 ), manganese, copper and iron contents decreased in cultivated areas. The AA has less nutrient content compared to AP in irrigated agriculture while in AP it is greater than AA under rainfed. Clay, TN, P 2 O 5 and available potassium (K 2 O) contents were correlated positively and highly significantly with OC and electrical conductivity (EC). In conclusion, the study revealed that most of the soil properties are influenced by land use management. Therefore, it could be recommended to include management practices that increase OC and TN in the system, when the land is continuously cultivated. Reclamation of the areas should start by considering available options like crop rotation as a good means of management. Keywords: Land use management, soil fertility soil nutrient, soil physicochemical properties

HARTLEY TRAVERS FERRAR (1879–1932) AND HIS GEOLOGICAL LEGACY IN ANTARCTICA, EGYPT AND NEW ZEALAND

ABSTRACT Hartley Travers Ferrar was the geologist on Scott's first expedition to the Antarctic (the ‘Discovery’ Expedition) in 1901–1904. Ferrar undertook the first geological surveys in the Transantarctic Mountains, which he mapped to 83°S, and made some discoveries of major scientific importance, such as fossil leaves, later identified as Glossopteris indica. He then worked in Egypt, Palestine and New Zealand, and was Acting Director of the New Zealand Geological Survey when he died suddenly in 1932. Little has been acknowledged about Ferrar's other contributions to geology, which were vast, and included pioneering work on irrigation and hydrogeology in Egypt, as well as a series of geological mapping campaigns in New Zealand. The latter extended to systematic soil surveys in New Zealand, in particular in Central Otago, where soil types and their properties were characterized in the field and laboratory. This paper outlines some of Ferrar's key contributions to New Zealand geoscience, as well as some of his notable overseas achievements.

Characterizing the Enduring Nature of Dryland Agro-ecosystems: Irrigated and Rain-fed Land Uses in Chamo Sub Basin, Southern Ethiopia

Characterizing soils, land use and providing suggestion for sustainable utilization of land resources in the Ethiopian Rift valley flat plain areas of Lake Chamo Sub-Basin is essential. The objectives of this study were, therefore, to characterize land use constraints and to assess the status of organic matter, macro and micro-nutrients and soil salinity for planning appropriate land management. A systematic soil survey and field observations weremade to gather information on land uses. Physiognomic vegetation classification was done in accordance with the FAO classification system, i.e. annual croppings, perennial croppings, grazing land and natural forest. A total of 120 soil samples were randomly collected from different land uses, which were prepared into 12 composites and analyzed in Ethiopia Water Works Design and Supervision Enterprise Laboratory. Organic matter, nitrogen, base saturation, exchangeable (potassium, calcium and magnesium), and phosphorus contents were low in cultivated soils compared to natural forest. Soil salinity was observed in irrigated banana and cotton field soils compared to rain-fed agriculture. Clay, nitrogen, phosphorus and potassium contents were positively correlated with organic matter and electrical conductivity. Also soluble cations and anions were varied along different land uses. Also, organic matter, exchangeable (sodium, calcium), cation exchange capacity, phosphorus and micronutrient contentswere positively correlated with soluble salts and electrical conductivity.

Factors affecting organic carbon dynamics in soils of Nepal/Himalayan region – a review and analysis

We reviewed the factors and processes relevant to C (Carbon) stocks and dynamics in the soils of Hindu Kush-Himalayan region (HKH) in general, and Nepal in particular. Included in this paper are reviews of land use change, soil types, erosion, soil fertility status, land management and other pertinent information in relation to the SOC (Soil Organic Carbon) stock, dynamics and sequestration. Watershed degradation in the HKH region appears to be a serious problem affecting the SOC pool, which may be primarily attributed to deforestation, land use changes, forest degradation, soil erosion and fertility decline. Soils under degraded forest and grazing land and red soils were reported to have less than 1% SOC; however, well managed forests have considerably higher organic matter (SOC = 4%) levels than those cleared for cultivation. Our estimates show that both the soil and SOC losses are site specific, being as high as 256 kg C ha–1 y–1. Estimated net CO2 losses from the erosion displaced SOC varied between <1 and 42 kg C ha–1 y–1 depending on initial SOC content and soil erosion rates in the specific sites. The land cover changes in the past 18 years in the two Nepalese watersheds, Mardi and Fewa, may have resulted in net loss of SOC stock (29% losses for Mardi and 7% losses for Fewa) compared to land cover in the base year (1978). The processes contributing to C pool, fluxes and sequestration are inadequately studied, and particularly in the HKH region, there is a lack of data on several essential aspects needed for estimating soil C fluxes and C sequestration potential. Systematic soil survey and long term experiments are needed on dominant soil types and land use systems of the HKH region for developing the database on soil fertility and SOC relationships to site specific management practices. Future research should focus upon generating data on spatial and temporal variation, depth distribution, quantification of various pools, and transport/translocation of SOC, as well as the establishment of soil/SOC databases, in relation to specific land use and management practices.

Retrospective monitoring and inventory of soil contamination in relation to systematic monitoring

Retrospective monitoring of soil contamination has been performed in the Czech Republic. This kind of monitoring is based on the comparison of the heavy metals content in soil samples taken during a systematic soil survey (1960-1970) and in samples taken at the present time. The anticipated high degree of soil pollution in the Czech Republic has not been proved. Most of the contaminated soils were found to be loaded just 20-35 years ago. Retrospective monitoring is considered to be an accelerating tool for determining the strategy of the systematic monitoring of soil contamination. This procedure stimulated the development of the multi-step system of soil loading limits.

Monitoring of agriculture soils in the Czech Republic

In the Czech Republic a complex monitoring of agriculture soils has commenced. This paper describes the approach to establishing monitoring plots. Comparing the results of Systematic Soil Survey and those from the first period of agriculture monitoring demonstrates that a representative set of plots was achieved. Soil properties (physical, chemical, biological and agronomical), atmospheric deposition (some parameters being monthly and some only for the summer and winter season) and selected other influences (application of pesticides, irrigation, etc.) are all monitored. Results for atmospheric deposition in the Czech Republic from the first period and Bavaria [Bayerische Landesanstalt für Bodenkultur und Pflanzenbau, 1992) are also compared. Data are evaluated by a statistical package (Statgrafics) and prepared for future transfer into a suitable GIS.

Trace elements in soils and crops.

To demonstrate the total amounts to be expected in soils, the ranges of contents of some 60 trace elements in ten representative Scottish arable surface soils are compared with ranges in soil-forming rocks and with crustal averages. It is, however, the amounts potentially available to plants rather than the total contents that are biologically significant. In temperate climates, trace element mobilization is greatest when weathering takes place under conditions of impeded pedological drainage, leading to the formation of gleyed soils. Mobilized trace elements occur in arable surface soils largely in adsorbed and chelated forms, which are available to plants to a greater or smaller extent depending on the prevailing soil parameters and on the element in question. Different species take up different amounts of trace elements: the proportions in the various plant parts vary with the element and the stage of growth. Information is required about the mobilization and uptake of many elements about which little is at present known but which may affect the functions of essential elements through inter-element interactions. Systematic soil surveys in which soils are mapped by associations related to parent material, with their series related to genetic soil types, provide a useful countrywide guide to trace element status.

Frost Weathering and Solifluction Products in Southern Scotland

Deposits occurring on hill slopes and mountain tops have been noted in various parts of Scotland, (A. Geikie, 1863; J. Geikie, 1869; Crampton and Carruthers, 1914; Simpson, 1932; Fitzpatrick, 1958; Galloway, 1961 and Tivy, 1962). Apart from Tivy's paper only a superficial description of the morphology of these deposits is given and, again excepting Tivy, there are no adequate descriptions of profiles or vertical sequences. Erosion surfaces have been described in detail and commented on widely in the geographical and geological literature but most of these papers imply that the upland slopes are bare, or almost bare, and that rock in situ lies close to the surface. While the authors acknowledge that there are many areas where rock does occur near the surface, the systematic soil survey of the higher parts of the Southern Uplands has revealed that a deep stony regolith occurs over much wider areas than was previously believed. This mantle was found to be an important parent material of rankers and podzolic soils. The resulting study will thus be of interest to those who interpret soils in the field as well as to geomorphologists. These deposits have been referred to variously as surface wash (Geikie, 1869), head and hill wash (Geological Survey), stony drift (Ragg, 1960) and slope deposits (Tivy, 1962). Deposits of this type at lower altitudes (< 450 m) in southern Scotland correlate with head, the term used in England for crudely stratified unsorted solifluction debris (Dines et al., 1940). The main subject of this paper is the nature and distribution of the deposits above 600 m which are vertically sorted and provide the raw material of the solifluction products below. Between 450 and 600 m there are materials of intermediate

Scientific Research in New Zealand

THE tenth annual report of the New Zealand Department of Scientific and Industrial Research covers the year 1935?36, and in addition to the Minister's statement and the Secretary's report, includes reports of the various research committees as well as of the Dominion Laboratory, the Geological Survey Branch, Meteorological Branch, and the Dominion, Apia, and Magnetic Observatories (Wellington: Government Printer, 1936. 2s. 3d.). Of the expenditure of £91,344 during the year, £46,306 was on research investigations, £11,225 of which was for industries and £21,360 in the Consolidated Fund. Plant research plays a large part in the activities of the Department, and has now been organized so that each Division is situated in the part of the Dominion most affected by its activities. General co-ordination of the work on animal health and nutrition has also been effected, and it is hoped that a comprehensive scheme of attack on these problems will be evolved during the year. A systematic soil survey of New Zealand is in progress and a survey of the tung oil industry will shortly be undertaken. Soil surveys form an important part of the investigations which are being made in the development of the citrus industry.