Predictive soil parent material mapping at a regional-scale: A Random Forest approach

AbstractDue to the special sensitivity of typical ecologically fragile areas, a series of human life, mining, and other activities have a greater impact on the environment. In this study, three coal mines in Ordos City on the Loess Plateau were selected as the study area, and the pollution levels of heavy metals in the area were studied by measuring As, Hg, Cr, Cd, Cu, Ni, and Pb in the soil of 131 sampling points. Combined with the concept of “co-occurrence network” in biology, the level of heavy metals in soil was studied using geostatistics and remote sensing databases. The results showed that the concentrations of Hg, Cr, Ni, Cu, and Pb in more than half of the sampling points were higher than the local environmental background value, but did not exceed the risk control value specified by China, indicating that human factors have a greater influence, while Cd and As elements are mainly affected Soil parent material and human factors influence. Heavy metal elements have nothing to do with clay and silt but have an obvious correlation with gravel. Cd, Pb, As and Ni, Cd, Cr are all positively correlated, and different heavy metals are in space The distribution also reflects the autocorrelation, mainly concentrated in the northeast of the TS mining area and the middle of the PS mining area.

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The influence of forest site on rate and extent of soil compaction and profile disturbance of skid trails during ground-based harvesting

Canadian Journal of Forest Research ◽

10.1139/x00-041 ◽

2000 ◽

Vol 30 (8) ◽

pp. 1196-1205 ◽

Cited By ~ 95

Author(s):

J R Williamson ◽

W A Neilsen

Keyword(s):

Root Growth ◽

Soil Compaction ◽

Forest Type ◽

Soil Bulk Density ◽

Parent Material ◽

Forest Site ◽

Undisturbed Soil ◽

Soil Parent Material ◽

Wet Forests

Soil compaction has been considered a principal form of damage associated with logging, restricting root growth and reducing productivity. The rate and extent of soil compaction on skid trails was measured at six field locations covering a range of dry and wet forests. Data was collected for up to 21 passes of a laden logging machine. A similar extent of compaction, averaging 0.17 g·cm-3 increase in total soil bulk density (BD), was recorded for all field sites despite substantial site and soil differences. On average, 62% of the compaction in the top 10 cm of the soil occurred after only one pass of a laden logging machine. The environment under which soils had formed played a major role in determining the BD of the undisturbed soil. Compaction was strongly related to the original BD, forest type, and soil parent material. Soil strengths obtained in the field fell below levels found to restrict root growth. However, reduction in macropores, and the effect of that on aeration and drainage could reduce tree growth. On the wettest soils logged, machine forces displaced topsoils rather than causing compaction in situ. Recommended logging methods and implications for the development of sustainability indices are discussed.

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Spatial Patterns and Drivers of Soil Chemical Properties in a Typical Hickory Plantation

10.21203/rs.3.rs-845777/v1 ◽

2021 ◽

Author(s):

Mengjiao Sun ◽

Enqing Hou ◽

Jiasen Wu ◽

Jianqin Huang ◽

Xingzhao Huang

Keyword(s):

Random Forest ◽

Soil Nutrients ◽

Spatial Patterns ◽

Abiotic Factors ◽

Soil Nutrient ◽

Parent Material ◽

Mean Annual Precipitation ◽

Nutrient Concentrations ◽

Available Phosphorus ◽

Mean Annual Temperature

Abstract Background: Soil nutrients play critical roles in regulating and improving the sustainable development of economic forests. Consequently, an elucidation of the spatial patterns and drivers of soil nutrients in these forests is fundamental to their management. For this study, we collected 314 composite soils at a 0-30 cm depth from a typical hickory plantation in Lin 'an, Zhejiang Province, China. We determined the concentrations of macronutrients (i.e., soil organic carbon, hydrolyzed nitrogen, available phosphorus, and available potassium) and micronutrients (i.e., iron, manganese, zinc, and copper.) of the soils. We employed random forest analysis to quantify the relative importance of soil-forming factors to predict the soil nutrient concentrations, which could then be extrapolated to the entire hickory region. Results: Random forest models explained 61%–88% of the variations in soil nutrient concentrations. The mean annual temperature and mean annual precipitation were the most important predictor of soil macronutrient and micronutrient concentrations. Moreover, parent material was another key predictor of soil available phosphorus and micronutrient concentrations. Mapping results demonstrated the importance of climate in controlling the spatial distribution of soil nutrient concentrations at finer scales, as well as the effect of parent material, topography, stand structure, and management measures of hickory plantations. Conclusions: Our study highlights the biotic factors, abiotic factors, and management factors control over soil macronutrient and micronutrient concentrations, which have significant implications for the sustainability of soil nutrients in forest plantations.

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Soil Parent Material, Weathering, and Primary Particles

Soils in Natural Landscapes ◽

10.1201/b15574-3 ◽

2013 ◽

pp. 13-34

Keyword(s):

Parent Material ◽

Soil Parent Material ◽

Primary Particles

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What drives forest fire in Fujian, China? Evidence from logistic regression and Random Forests

International Journal of Wildland Fire ◽

10.1071/wf15121 ◽

2016 ◽

Vol 25 (5) ◽

pp. 505 ◽

Cited By ~ 27

Author(s):

Futao Guo ◽

Guangyu Wang ◽

Zhangwen Su ◽

Huiling Liang ◽

Wenhui Wang ◽

...

Keyword(s):

Logistic Regression ◽

Random Forest ◽

Regional Scale ◽

Fire Risk ◽

Driving Factors ◽

Fire Season ◽

Fire Occurrence ◽

Climate Factors ◽

Local Factors ◽

Risk Zones

We applied logistic regression and Random Forest to evaluate drivers of fire occurrence on a provincial scale. Potential driving factors were divided into two groups according to scale of influence: ‘climate factors’, which operate on a regional scale, and ‘local factors’, which includes infrastructure, vegetation, topographic and socioeconomic data. The groups of factors were analysed separately and then significant factors from both groups were analysed together. Both models identified significant driving factors, which were ranked in terms of relative importance. Results show that climate factors are the main drivers of fire occurrence in the forests of Fujian, China. Particularly, sunshine hours, relative humidity (fire seasonal and daily), precipitation (fire season) and temperature (fire seasonal and daily) were seen to play a crucial role in fire ignition. Of the local factors, elevation, distance to railway and per capita GDP were found to be most significant. Random Forest demonstrated a higher predictive ability than logistic regression across all groups of factors (climate, local, and climate and local combined). Maps of the likelihood of fire occurrence in Fujian illustrate that the high fire-risk zones are distributed across administrative divisions; consequently, fire management strategies should be devised based on fire-risk zones, rather than on separate administrative divisions.

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THE EFFECT OF DRAINAGE CONDITION ON THE REDOX POTENTIAL, LEACHATE COMPOSITION AND MORPHOLOGICAL CHARACTERISTICS OF A SOIL PARENT MATERIAL STUDIED IN THE LABORATORY

Canadian Journal of Soil Science ◽

10.4141/cjss60-017 ◽

1960 ◽

Vol 40 (2) ◽

pp. 121-129 ◽

Cited By ~ 1

Author(s):

J. A. McKeague ◽

C. F. Bentley

Keyword(s):

Redox Potential ◽

Water Table ◽

Morphological Characteristics ◽

Parent Material ◽

Soil Material ◽

Soil Parent Material ◽

Leachate Analysis ◽

Loam Soil ◽

Leachate Composition ◽

Measurable Change

Plastic columns containing a calcareous clay loam soil parent material with and without ground aspen leaves at the surface were maintained under different drainage conditions for 32 months. Distilled water was added at regular intervals. Results of redox potential (Eh) measurements at four depths, leachate analysis and analysis of the soil material are presented.With water table to the surface and a layer of surface leaves, low Eh readings and appreciable iron movement resulted. In a column with fluctuating water table and surface leaves, raising the water table brought about a decrease in the Eh of the soil below the water table. Height of water table had no effect on the Eh of a column which had no leaves at the surface. In columns where the soil material was mixed with quartz sand, leaching brought about marked downward movement of silt and clay size particles. Apart from the removal of soluble salts, there was little measurable change in columns which had no admixture of sand.

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