Soil Monitoring Data Research Articles

A detrimental soil disturbance prediction model for ground-based timber harvesting

Soil properties and forest productivity can be affected during ground-based harvest operations and site preparation. The degree of impact varies widely depending on topographic features and soil properties. Forest managers who understand site-specific limits to ground-based harvesting can alter harvest method or season to limit soil disturbance. To determine the potential areal extent of detrimental (potentially plant growth limiting) soil disturbance based on site characteristics and season of harvest, we developed a predictive model based on soil monitoring data collected from 167 ground-based harvest units. Data collected included dominant site parameters (e.g., slope, aspect, soil texture, and landtype), harvest season, harvest type (intermediate or regeneration), and the machine(s) used during ground-based harvest operations. Aspect (p = 0.0217), slope (p = 0.0738), landtype (p = 0.0002), and the interaction of harvest season × landtype (p = 0.0002) were the key variables controlling the areal extent and magnitude of detrimental soil disturbance. For example, harvesting during non-winter months on gently rolling topography resulted in greater soil disturbance than similar harvest operations on landscapes that are highly dissected. This is likely due to the ease with which equipment can move off designated trails. A geospatially explicit predictive model was developed using general linear model variables found to significantly influence the areal extent of detrimental soil disturbance on nine defined landtypes. This tool provides a framework that, with local calibration, can be used on other forest lands as a decision support tool to geospatially depict landtypes susceptible to detrimental soil disturbance during ground-based harvest operations.

Modelling soil organic carbon concentration of mineral soils in arable land using legacy soil data

Soil organic carbon (SOC) concentration is an essential factor in biomass production and soil functioning. SOC concentration values are often obtained by prediction but the prediction accuracy depends much on the method used. Currently, there is a lack of evidence in the soil science literature as to the advantages and shortcomings of the different commonly used prediction methods. Therefore, we compared and evaluated the merits of the median approach, analysis of covariance, mixed models and random forests in the context of prediction of SOC concentrations of mineral soils under arable management in the A‐horizon. Three soil properties were used in all of the developed models: soil type, physical clay content (particle size <0.01 mm) and A‐horizon thickness. We found that the mixed model predicted SOC concentrations with the smallest mean squared error (0.05%2), suggesting that a mixed‐model approach is appropriate if the study design has a hierarchical structure as in our scenario. We used the Estonian National Soil Monitoring data on arable lands to predict SOC concentrations of mineral soils. Subsequently, the model with the best prediction accuracy was applied to the Estonian digital soil map for the case study area of Tartu County where the SOC predictions ranged from 0.6 to 4.8%. Our study indicates that predictions using legacy soil maps can be used in national inventories and for up‐scaling estimates of carbon concentrations from county to country scales.

Deformation damages in forest topsoils—An assessment based on Level‐I soil monitoring data from Baden‐Württemberg (SW Germany)

AbstractAcidification and eutrophication of soils had been the main activators for the implementation of forest soil monitoring in Central Europe. Thus, field and lab studies focused on gathering information that is essential for the evaluation of the chemical status and its trend. A systematic assessment of soil physical threats caused by machine use in forests has not been integrated yet into the soil‐monitoring systems. In this study, a first approach to get a deeper insight into structure damages of forest topsoils was derived for 302 systematically distributed grid points in the Federal State of Baden‐Württemberg (SW Germany) during the nation‐wide soil survey performed from 2006 to 2008. We derived an approach to assess structure damage based on a key system using field information on structural and hydromorphic topsoil properties. It covers eight satellites surrounding the central monitoring soil pit at each grid point. Our survey focused on the mere stand area excluding visible damage and systematic skid trails. Analysis of structure‐damage intensity and spatial distribution leads to the conclusion that damage caused by vehicle traffic off the skid trails is a wide‐spread phenomena in Baden‐Württemberg forests, where wheeling is not restricted by steepness of terrain. Although regulations to control machine use recommending vehicle traffic to skid trails and fortified roads have been in place since the early 1980s, soil‐structure damages off these trails have reached significant levels. In the future, it will thus be indispensable to put more emphasis on the importance of soil‐protection aims in the ranking of the economic objectives of forest organizations and forest owners.

Availability and evaluation of European forest soil monitoring data in the study on the effects of air pollution on forests

In the study of air pollution effects on forest ecosystems, solid soil data such as cation exchange capacity, base saturation and other exchangeable cation fractions, soil texture, soil moisture, soil weathering rates, C/N ratio and other variables form an important information base for many air pollution impact models. This paper shows some of the possibilities and the limitations of the soil data that European countries collected on the systematic Level I and on the intensive and permanent Level II monitoring plots within the ICP Forests programme. The soil data date from a first inventory in the 1990s and from a second inventory more than 10 years later. Both surveys were conducted following a common manual on sampling and analysis of soil. An example of the changes in pH(CaCl2) and base saturation in the forest floor and mineral soil on more than 2000 plots till a depth of 80 cm between the two surveys is presented. In this period the pH(CaCl2) significantly increased in the very acid forest soils [with pH(CaCl2) below 4.0] but further decreased in forest soils with pH(CaCl2) above 4.0. Following the trend in pH, the base saturation increased in soils with a very low buffering capacity (soils with a base saturation below 20% in the first inventory) and decreased in forest soils with reference base saturation values above 20%. There is both a decrease of soil pH and base saturation in the forest floor of the Arenosols and Podzols. In the Podzols this decreasing trend could not be established in the mineral soil, though this decreasing trend persisted in a number of mineral soil layers of the Arenosols. The only consistent increasing trend of pH and base saturation when stratifying according to the WRB reference soil groups was seen in the forest floor of the Luvisols and Cambisols.

Construction of a chemical ranking system of soil pollution substances for screening of priority soil contaminants in Korea

The Korean government recently proposed expanding the number of soil-quality standards to 30 by 2015. The objectives of our study were to construct a reasonable protocol for screening priority soil contaminants for inclusion in the planned soil quality standard expansion. The chemical ranking system of soil pollution substances (CROSS) was first developed to serve as an analytical tool in chemical scoring and ranking of possible soil pollution substances. CROSS incorporates important parameters commonly used in several previous chemical ranking and scoring systems and the new soil pollution parameters. CROSS uses soil-related parameters in its algorithm, including information related to the soil environment, such as soil ecotoxicological data, the soil toxic release inventory (TRI), and soil partitioning coefficients. Soil TRI and monitoring data were incorporated as local specific parameters. In addition, CROSS scores the transportability of chemicals in soil because soil contamination may result in groundwater contamination. Dermal toxicity was used in CROSS only to consider contact with soil. CROSS uses a certainty score to incorporate data uncertainty. CROSS scores the importance of each candidate substance and assigns rankings on the basis of total scores. Cadmium was the most highly ranked. Generally, metals were ranked higher than other substances. Pentachlorophenol, phenol, dieldrin, and methyl tert-butyl ether were ranked the highest among chlorinated compounds, aromatic compounds, pesticides, and others, respectively. The priority substance list generated from CROSS will be used in selecting substances for possible inclusion in the Korean soil quality standard expansion; it will also provide important information for designing a soil-environment management scheme.

Soil bulk density pedotransfer functions of the humus horizon in arable soils

Soil bulk density (D b) is an important indicator of soil quality, site productivity and soil compaction and is widely used as an input variable for various models. However, D b is often not determined during actual soil surveys, and many attempts have been made to predict it from other more easily and routinely measured variables. The aim of this study was to develop a predictive model for D b estimation for the humus horizon of arable soils. In addition, we hypothesised that the mixed model approach would enable more accurate predictions than the multiple regression model. Estonian National Soil Monitoring data (1983–2008) were used for D b modelling. The dataset contains 17,293 entries for the humus horizon of Estonian arable soils. Mixed model methodology and linear multiple regression analysis were used to develop prediction models. Soil sampling depth, soil organic carbon and water content had the greatest effects on D b estimation. D b is determined through interactions of explanatory variables, and their contribution to D b variation in mixed model differs from variable contribution indicated by the simple regression model. We found that the regression model overestimates the importance of SOC. The mixed model prediction was an improvement compared to multiple regression models (MSE = 0.009 compared to MSE = 0.014). In addition, the predicted values in the mixed model showed good agreement with observed values, while the multiple regression model underestimated D b values above 1.6 g cm −3 and overestimated D b values below 1.2 g cm −3. We conclude that the mixed model approach enables higher prediction accuracy than multiple regression analysis. We propose a mixed model with 20 variables as a prediction model for the humus horizon of Estonian arable soils. The methodology is also applicable for other soil conditions.

SOIL AND WATER SALINITY, THEIR MANAGEMENT IN RELATION TO CLIMATE CHANGES IN COASTAL AREAS OF BANGLADESH

Climate change due to global warming and its negative consequence on environment and agro ecosystem is a serious concern of global community of current age. To assess the present soil and water salinity status in coastal areas a soil survey work following standard methods has been completed by Soil Resource Development Institute (SRDI) in 2009. It was observed that out of 2.86 million hectares of coastal and offshore lands about 1.056 million ha of arable lands are affected by varying degrees of salinity. A comparative study of the salt affected area between 1973 to 2009 showed that about 0.223 million ha (26.7%) new land was affected by various degree of salinity during last four decades . It was also observed that about 0.035 million hectares of land (3.5%) new land was affected by various degrees of salinity during last 9 years only (2000-2009). High amount of S and high pH may be the possible causes for P deficiency in coastal areas. Coastal soils are rich in micronutrient elements except Zn. In shrimp cultivated areas flooding with high saline water for a considerable time in each year causing higher soil salinity in all the horizons. A long term soil and water salinity monitoring data of SRDI shows that soil and water salinity between 1991 and 2008 has increased at least 2-10 times. Several common and location specific agricultural constraints have been identified in the field through field investigation/observation and farmer’s interview. Proper fertilizer management practices need to be addressed in coastal saline areas.
 

Broadband Apparent Permittivity Measurement in Dispersive Soils Using Quarter‐Wavelength Analysis

Time‐domain reflectometry (TDR) has, since the early 1980s, become a widely used and robust method for measuring the electromagnetic properties of soils. Although it allows use of relatively simple probes and measurement equipment that free users from complex analysis of small soil samples in the laboratory, it provides little information on the dispersive nature of fine‐grained soils. Therefore, we developed a quarter‐wavelength analysis (QWA) methodology that allows apparent permittivity spectra to be obtained for soils, while retaining the same range of cells and probes and the simplicity of data analysis associated with TDR. We tested the technique on clay soils across a wide water content range and found that it provided useful data for frequencies ranging from approximately 100 MHz to >1 GHz—the accuracy being considered no worse than two units of apparent permittivity. The results show that the methodology is capable of providing broadband dispersion data that give significantly greater detail on soil electromagnetic properties than can be expected from single‐frequency TDR data. This has a number of important advantages including the potential to provide accurate water content measurements in clay soils, a means to extend TDR soil monitoring data, and the opportunity to validate research into the measurement frequency associated with simple TDR measurements and time‐ to frequency‐domain inversions.

Land-use induced changes in topsoil organic carbon stock of paddy fields using MODIS and TM/ETM analysis: A case study of Wujiang County, China

Topsoil soil organic carbon (SOC) that plays an important role in mitigating atmospheric carbon dioxide (CO2) buildup is greatly affected by human activities. To evaluate the influence of land-use changes on SOC stocks in paddy soils, a new algorithm was developed by integrating MODIS (moderate resolution imaging spectral-radiometer) and TM/ETM data for timely monitoring the land-use change in Wujiang County. Thereafter, the land-use class-maps derived from MODIS and TM/ETM analyses were further used to estimate land use-induced carbon (C) pool changes in paddy topsoil of Wujiang County based upon the nationwide arable soil monitoring data and county level SOC reconnaissance data in 2003. The results showed that irrigation-based rice cultivation in Wujiang County has resulted in SOC content at an annual increasing rate of 0.01 g/kg over the period of 1984-2003, while the density of SOC in uplands and woodlands has decreased. Annual decreasing rate of SOC content was estimated to be 0.03 g/kg in uplands and 0.06 g/kg in woodlands. The total topsoil SOC stocks in paddy fields of Wujiang County have increased from 2.67 x 10(6) t C in 1984 to 2.69 x 10(6) t C in 2005. During 1984-2005, the total SOC sequestrations in rice paddies were greater than the SOC losses in woodlands and uplands. The temporal C loss might have exceeded the SOC sequestration in rice paddies due to their conversion to nursery lands and uplands since 2001. The results of this study suggest that changes of land use have a great influence on soil C sequestration, particularly on C stocks and C sequestration potential in paddy fields in developed areas of China.

Zoning of forest health conditions based on a set of soil, topographic and vegetation parameters

Saxony, a federal state in the east of Germany, includes regions with a history of high deposition rates of total acidity and conspicuous impairments of the health status of forests and forest soils. Both the reduction of SO 2 immissions and extensive forest liming campaigns have led to a visible regeneration of forests, especially in the Saxon low mountain ranges. There is a strong need for maps with landscape-related information about the forest health status as a basis for an ecological underpinning of forest management practices. The aim of the analyses presented was to derive a zoning of forest health conditions in Saxony on the basis of soil, topographic and vegetation parameters. The upscaling approach of the present paper is based on multiple linear regression analyses coupled with geostatistics using a two-stage procedure with global and regional transfers. First, the forest soil monitoring data of Saxony were evaluated using variables derived from a digital terrain model, geological information and soil and stand related parameters available in high spatial resolution as independent variables. In a second step the influence of environmental factors on the medium-term crown defoliation was analysed using the modelling results from step 1 (regionalized soil chemical attributes) as additional auxiliary variables. Spatio-temporally limited damaging events were diminished by the plot-wise and temporal aggregation of defoliation values. Unlike soil chemical data, it was not possible to detect clear auto-correlative spatial structures for defoliation measurements due to the influence of stand age. About 70–80% of the total variance of defoliation could be explained by the multiple linear regression models. Methodological limitations and interpretations are discussed. Stand age, with 35–64% of the explained variance, showed by far the highest influence. This confirms the necessity to quantify the influence of the stand age as a systematic and intrinsic natural factor if the relationship between defoliation and stress factors is intended to be examined. The model performance of the regression algorithms was examined using both an independent validation procedure and cross-validation terms. Finally, the modelled “mean level of defoliation” was mapped using the mean stand age of forests in Saxony (60 years) by means of regression equations as scenario models.

Deep vadose zone hydrology demonstrates fate of nitrate in eastern San Joaquin Valley

The sustainability of water resources is key to continued prosperity in the San Joaquin Valley and California. The vadose zone is an often-ignored layer of wet but unsaturated sediments between the land surface and the water table. It plays an important role in groundwater recharge and in controlling the flux and attenuation of nitrate and other potential groundwater contaminants. In a former orchard at the UC Kearney Research and Extension Center, we investigated the processes that control the movement of water, nitrate and other contaminants through the deep vadose zone. These processes were found to be controlled by the alluvial sedimentary geology of the vadose zone, which is highly heterogeneous. This heterogeneity should be considered when interpreting soil and deep vadose zone monitoring data and assessing of the leaching potential of agricultural chemicals. The transport of contaminants through the vadose zone may be significantly faster than previously assumed, while denitrification is likely limited or insignificant in the oxic, alluvial vadose zone of the eastern San Joaquin Valley.

RELATIONS BETWEEN MORPHOLOGICAL COLOR INDEX AND SOIL WETNESS CONDITION OF ANTHRAQUIC SOILS IN TAIWAN

The unique hydrologic and soil morphological features of the lowland rice-growing areas of the Chungli Terrace in northern Taiwan derive from diluvium red soils. Soil morphological characteristics and monitoring data provide a long-term record of the hydrological period and are useful for identifying these soils as hydric soils. The objective of this study was to establish relationships between the soil morphology-based soil chroma index and soil wetness conditions, including annual duration of both saturation and reduction. Three transects of a toposequence ranging from 20 to 40 m were selected. Four soils (Plinthaqualfs and Plinthaquults) were located in the toeslope position (20 m), four soils (Plinthudults and Paleudalfs) in the footslope position (30 m), and three soils (Paleudults and Paleudalfs) in the backslope position (40 m) with different redoximorphic features. Because they are seasonally flooded for rice (Oryza sativa L.) production and have perched water tables from February to October, all of these soils are considered to be anthraquic. Seasonally high groundwater levels also occurred during the growing season. Soils in three transects were monitored for groundwater depth, matric potential, and redox potential. The analytical results revealed that the seven soils with A horizons ≤ 25 cm thick were all hydric soils based on redox potential monitoring data. The analytical results indicated significant correlations between the chroma index and saturation time of year at 50-100 cm depth (P < 0.05) and at 100-150 cm depth (P < 0.01). A significant correlation was also found between chroma index and duration of reduction at depths of 50-100 cm (P < 0.01) and 100-150 cm (P < 0.01). However, no clear correlation existed for depths of <50 cm because of the disturbance associated with plowing and the accumulation of rice straw residual on the soil surface.

Arsenic levels in the soils and macrophytes of the ‘Entremuros’ after the Aznalcóllar mine spill

In April 1998, a holding lagoon containing pyrite ore processing waste rich in arsenic, failed and released 5–6 million m 3 of highly polluting sludge and acidic water. Over 2700 ha of the internationally important Doñana National and Natural Parks were contaminated. The area of Natural Park to sustain the greatest impact was known as the Entremuros. This paper presents 0–5 cm soil monitoring data from the Entremuros, from sampling campaigns 6 and 18 months after the disaster; as well as macrophyte root, rhizome and stem data from samples taken 18 months after the spill. Results show a clear, decreasing, north–south arsenic soil pollution trend, both 6 and 18 months after the spill, and suggest a small reduction in total soil arsenic levels occurred over time; although a significant increase in extractable arsenic is also noted. The two macrophytes ( Typha dominguensis and Scirpus maritimus) studied herein are not accumulating arsenic in stem parts, however, accumulation of arsenic on iron plaque on the roots of these plants may be occurring. Further work is recommended in order to determine the ecotoxicological significance of this process in relation to the avian food-chains of Doñana, and elsewhere.

Storage and sequestration potential of topsoil organic carbon in China's paddy soils

AbstractCarbon (C) storage and sequestration in agricultural soils is considered to be an important issue in the study of terrestrial C cycling and global climatic change. The baseline C stock and the C sequestration potential are among the criteria for a region or a state to adopt strategies or policies in response to commitment to the Kyoto Protocol. Paddy soils represent a large portion of global cropland. However, little information on the potential of C sequestration and storage is available for such soils. In this paper, an estimation of the topsoil soil organic carbon (SOC) pool and the sequestration potential of paddy soils in China was made by using the data from the 2nd State Soil Survey carried out during 1979–1982 and from the nationwide arable soil monitoring system established since then. Results showed that the SOC density ranged from 12 to 226 t C ha−1 with an area‐weighted mean density of 44 t C ha−1, which is comparable to that of the US grasslands and is higher than that of the cultivated dryland soils in China and the US. The estimated total topsoil SOC pool is 1.3 Pg, with 0.85 Pg from the upper plow layer and 0.45 Pg from the plowpan layer. This pool size is ∼2% of China's total storage in the top 1 m of the soil profiles and ∼4% of the total topsoil pool, while the area percentage of paddy soil is 3.4% of the total land. The C pool in paddy soils was found predominantly in southeast China geographically and in the subgroups of Fe‐accumulating and Fe‐leaching paddy soils pedogenetically. In comparison with dryland cultivation, irrigation‐based rice cultivation in China has induced significant enrichment of SOC storage (0.3 Pg) in paddy soils. The induced total C sequestration equals half of China's total annual CO2 emission in the 1990s. Estimates using different SOC sequestration scenarios show that the paddy soils of China have an easily attainable SOC sequestration potential of 0.7 Pg under present conditions and may ultimately sequester 3.0 Pg. Soil monitoring data showed that the current C sequestration rate is 12 Tg yr−1. The total C sequestration potential and the current sequestration rate of the paddy soils are over 30%, while the area of the paddy soils is 26% that of China's total croplands. Therefore, practicing sustainable agriculture is urgently needed for enhancing SOC storage to realize the ultimate SOC sequestration of rice‐based agriculture of China, as the current C sequestration rate is significantly lower than the potential rate.

Development of a Soil, Surface-Water, and Groundwater Remediation Program for the Accidental Crude-Oil Spill that Occurred on July 16, 2000 at the Petrobras Refinery Refinaria Presidente GetúLio Vargas-Repar, Araucária, Brazil – PR

ABSTRACT On July 16, 2000, a crude oil spill occurred at the PETROBRAS refinery Refinaria Presidente Getúlio Vargas-REPAR, located in Araucária, PR, Brazil. A significant quantity of oil was retained within an area known as Ponto 0, between the spill site and Rio Barigüi, contaminating the hanks of a small stream (Arroio Saldanha), the soil adjacent to the stream, and the soil of four small wetlands, over a distance of 2 km. This paper presents an overview of the remediation program for Ponto 0, and draws preliminary conclusions regarding the efficacy of different remediation technologies. The major remediation technologies are: 1) injection and recovery trenches for free-product recovery in the sector adjacent to the spill site; 2) in situ bioremediation along the floodplain of Arroio Saldanha; and 3) a treatment wetland near the discharge of Arroio Saldanha into Rio Barigüi. The trenches appear to have removed most of the free product from the sector adjacent to the spill site. There is preliminary evidence, based on soil monitoring data, for the efficacy of in situ bioremediation, but further data will be required before a firm conclusion can be drawn. The treatment wetland was successful in restoring wetland vegetation (an essential component of this technology), and appears to be capable of removing hydrocarbons from groundwater. Data of the groundwater monitoring program indicates a general decline in TPH concentrations, over the October 2000, August 2001 and April 2002 sampling campaigns. BTEX concentrations are generally below the method detection limit.

The behavior of tritium oxide: Model experiments under natural conditions

The authors have created a regional geological model to depict the concentration, retention, and migration of tritium oxides deposited in soil as a result of rain or snow and absorbed by ground water as well as vegetation. The model incorporates seasonal meteorological and moisture variations along with surface air and soil monitoring data and also includes plant growth data as a result of tritium oxide uptake. The model consists of three experimental areas of 100 square meters each in a woodland-steppe region of the Soviet Union. The soil cover consisted of leached black earth and the vegetation consisted of a cereal-herbage field. Observations were made during the first two years after contamination and ten to twelve years later.