80% of arable land in Africa has low soil fertility and suffers from physical soil problems. Addi... more 80% of arable land in Africa has low soil fertility and suffers from physical soil problems. Additionally, significant amounts of nutrients are lost every year due to unsustainable soil management practices. This is partially the result of insufficient use of soil management knowledge. To help bridge the soil information gap in Africa, the Africa Soil Information Service (AfSIS) project was established in 2008. Over the period 2008-2014, the AfSIS project compiled two point data sets: the Africa Soil Profiles (legacy) database and the AfSIS Sentinel Site database. These data sets contain over 28 thousand sampling locations and represent the most comprehensive soil sample data sets of the African continent to date. Utilizing these point data sets in combination with a large number of covariates, we have generated a series of spatial predictions of soil properties relevant to the agricultural management-organic carbon, pH, sand, silt and clay fractions, bulk density, cation-exchange c...
This chapter reviews both rain gauge (point) data sources and remote-sensing (visible, thermal IR... more This chapter reviews both rain gauge (point) data sources and remote-sensing (visible, thermal IR and microwave (MW)) imagery sources used for producing precipitation maps, and then shows “in action” a number of mechanical and stochastic spatial prediction methods that can be used to generate maps of rainfall intensity. Special focus was put on using geostatistical techniques implemented in the R environment for statistical computing (via stats, gstat, and geoR packages). The spatial prediction methods are illustrated using ...
Proceedings of the 5th Global Workshop on Digital Soil Mapping 2012, Sydney, Australia, 2012
ABSTRACT: This paper reviews the design and functionality of a data portal and repository of grid... more ABSTRACT: This paper reviews the design and functionality of a data portal and repository of gridded layers for global soil mapping—WorldGrids. org. WorldGrids. org is a component of the GSIF (Global Soil Information Facilities), ISRIC's framework for production of open soil data with global coverage. GSIF has been inspired by global environmental data initiatives (such as the oneGeology, GBIF, global land cover and meteorological mapping initiatives). The main practical motivation for GSIF is to build a cyber-infrastructure to collate legacy (ie ...
ABSTRACT Geomorphology may be defined as the science, which studies the nature and history of lan... more ABSTRACT Geomorphology may be defined as the science, which studies the nature and history of landforms, and the processes that created them. This chapter focuses on the uses of digital elevation models (DEMs) for geomorphological mapping that is, extraction of geological and geomorphological features out of DEMs. Basic concepts in geomorphology include the magnitude and frequency of processes, spatial scales of landforms and processes, temporal scales of adjustment, equilibrium and historical inheritance, relations between internal and external processes, and the sediment cascade. Most of these involve the use of geomorphometric measures, increasingly from DEMs. A major application of geomorphometry in geomorphological studies is the automated extraction of geological/hydrological features and landforms. Using a small case study, the chapter demonstrates various approaches to extraction of predefined, generic, and empirically defined landform objects. It has also shown that geomorphometry has gone beyond the experimental stage and produced many substantive results in geomorphology.
Wind erosion submits fine as well as coarse soil particles into the atmosphere, thereby affecting... more Wind erosion submits fine as well as coarse soil particles into the atmosphere, thereby affecting physical and chemical processes, affecting radiative forcing, chemical reactions and biological systems. This study was conducted to quantify wind erosion events by generating data for soil erodibility and wind erosivity for the Danube Basin. Estimates of surface soil texture were generated from∼ 8,000 soil profiles and 54 auxiliary datasets using the regression-kriging method. The quality of the regression equation was not ...
Summary This chapter includes the minutes of the JRC workshop in Zagreb and some basic conclusion... more Summary This chapter includes the minutes of the JRC workshop in Zagreb and some basic conclusions. The chapter is organized as follows. In the first part the background information of this meeting and the main points are presented. The first day of the meeting was dedicated to the overview of soil information in each of the Southern-Eastern European countries. In the related section, brief description of all presentations is listed. The second day has been divided into two sessions: the first session was dedicated to the European ...
80% of arable land in Africa has low soil fertility and suffers from physical soil problems. Addi... more 80% of arable land in Africa has low soil fertility and suffers from physical soil problems. Additionally, significant amounts of nutrients are lost every year due to unsustainable soil management practices. This is partially the result of insufficient use of soil management knowledge. To help bridge the soil information gap in Africa, the Africa Soil Information Service (AfSIS) project was established in 2008. Over the period 2008-2014, the AfSIS project compiled two point data sets: the Africa Soil Profiles (legacy) database and the AfSIS Sentinel Site database. These data sets contain over 28 thousand sampling locations and represent the most comprehensive soil sample data sets of the African continent to date. Utilizing these point data sets in combination with a large number of covariates, we have generated a series of spatial predictions of soil properties relevant to the agricultural management-organic carbon, pH, sand, silt and clay fractions, bulk density, cation-exchange c...
This chapter reviews both rain gauge (point) data sources and remote-sensing (visible, thermal IR... more This chapter reviews both rain gauge (point) data sources and remote-sensing (visible, thermal IR and microwave (MW)) imagery sources used for producing precipitation maps, and then shows “in action” a number of mechanical and stochastic spatial prediction methods that can be used to generate maps of rainfall intensity. Special focus was put on using geostatistical techniques implemented in the R environment for statistical computing (via stats, gstat, and geoR packages). The spatial prediction methods are illustrated using ...
Proceedings of the 5th Global Workshop on Digital Soil Mapping 2012, Sydney, Australia, 2012
ABSTRACT: This paper reviews the design and functionality of a data portal and repository of grid... more ABSTRACT: This paper reviews the design and functionality of a data portal and repository of gridded layers for global soil mapping—WorldGrids. org. WorldGrids. org is a component of the GSIF (Global Soil Information Facilities), ISRIC's framework for production of open soil data with global coverage. GSIF has been inspired by global environmental data initiatives (such as the oneGeology, GBIF, global land cover and meteorological mapping initiatives). The main practical motivation for GSIF is to build a cyber-infrastructure to collate legacy (ie ...
ABSTRACT Geomorphology may be defined as the science, which studies the nature and history of lan... more ABSTRACT Geomorphology may be defined as the science, which studies the nature and history of landforms, and the processes that created them. This chapter focuses on the uses of digital elevation models (DEMs) for geomorphological mapping that is, extraction of geological and geomorphological features out of DEMs. Basic concepts in geomorphology include the magnitude and frequency of processes, spatial scales of landforms and processes, temporal scales of adjustment, equilibrium and historical inheritance, relations between internal and external processes, and the sediment cascade. Most of these involve the use of geomorphometric measures, increasingly from DEMs. A major application of geomorphometry in geomorphological studies is the automated extraction of geological/hydrological features and landforms. Using a small case study, the chapter demonstrates various approaches to extraction of predefined, generic, and empirically defined landform objects. It has also shown that geomorphometry has gone beyond the experimental stage and produced many substantive results in geomorphology.
Wind erosion submits fine as well as coarse soil particles into the atmosphere, thereby affecting... more Wind erosion submits fine as well as coarse soil particles into the atmosphere, thereby affecting physical and chemical processes, affecting radiative forcing, chemical reactions and biological systems. This study was conducted to quantify wind erosion events by generating data for soil erodibility and wind erosivity for the Danube Basin. Estimates of surface soil texture were generated from∼ 8,000 soil profiles and 54 auxiliary datasets using the regression-kriging method. The quality of the regression equation was not ...
Summary This chapter includes the minutes of the JRC workshop in Zagreb and some basic conclusion... more Summary This chapter includes the minutes of the JRC workshop in Zagreb and some basic conclusions. The chapter is organized as follows. In the first part the background information of this meeting and the main points are presented. The first day of the meeting was dedicated to the overview of soil information in each of the Southern-Eastern European countries. In the related section, brief description of all presentations is listed. The second day has been divided into two sessions: the first session was dedicated to the European ...
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Papers by Tomislav Hengl