Exploring the potential offered by legacy soil databases for ecosystem services mapping of Central African soils

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Geospatial Information as a Tool for Soil Resource Information, Management and Decision Support in Nigeria

Understanding and addressing the complexity of soil resources management and factors involved requires collection and interpretation of relevant data that will serve as decision support tools. Geospatial information is a veritable tool for soil resource information and decision support for soil management, which is yet to be well embraced in Nigeria. This paper emphasized the importance of geospatial information as a decision support tool to make better and informed decision in the management of soil resources. It also reviewed and discussed status of soil information systems and need to promote strategies for sustainable soil resource development in the country.Keywords: Soil information system, Decision support system, remote sensing, digital soil mappin

Tracing sources of cadmium in agricultural soils: a stable isotope approach

Cadmium (Cd) is a biotoxic heavy metal, which is accumulated by plants and animals and thereby enters the human food chain (Gray et al. 2003). The application of phosphate fertilisers has also resulted in the long-term accumulation of Cd in agricultural soils around the world, including New Zealand (NZ). In 1997, the main source of NZ phosphate fertilisers was changed from Nauru island phosphate rocks (450 mg Cd kg-1 P) to a variety of phosphate rocks with lower Cd concentrations, in order to meet more stringent Cd limits in P fertiliser. Following this change, the accumulation of Cd in topsoil samples from the Winchmore research farm (South Island, NZ) was evaluated and was found to have plateaued post-2000 (McDowell, 2012). In this study, stable isotope analysis was used to trace the fate of Cd in Winchmore farm soils in order to determine the cause of the plateau. The isotope ratio of Cd (δ114/110Cd) was measured in pre-2000 and post-2000 phosphate fertilisers, phosphate rocks, topsoil (0-7.5 cm) and control (unfertilised) subsoil (25-30 cm) samples from the Winchmore site. The analysed topsoil samples were archived samples collected over the period 1959-2015. The isotopic compositions of fertilised topsoils ranged from δ114/110Cd = 0.08 ± 0.03 to δ114/110Cd = 0.27 ± 0.04, which were comparable to pre-2000 fertilisers (δ114/110Cd = 0.10 ± 0.05 to 0.25 ± 0.04) but distinct from the post-2000 fertilisers (δ114/110Cd range of -0.17 ± 0.03 to 0.01 ± 0.05) and control subsoil (δ114/110Cd = -0.33 ± 0.04) (Salmanzadeh et al., 2017). We combined this stable isotope data with Bayesian modelling to estimate the contribution of different sources of Cd. An open source Bayesian isotope mixing model implemented in Matlab (Arendt et al., 2015) was used here with some modifications to estimate the fractional contribution of different sources of Cd through time including pre- and post-2000 fertilisers, and the control soil. The Matlab code of Arendt et al., 2015 was modified to consider only one isotope system (rather than two), and fewer sources. This modelling confirmed the dominant contribution (about 80%) of Nauru-derived (i.e. pre-2000) fertilisers in increasing the Cd concentration in Winchmore soils. To help constrain the soil Cd mass balance we used an existing model (CadBal) (Roberts and Longhurst, 2005), to estimate residual soil Cd and output fluxes based on known P fertiliser application rates, the initial Cd concentration, farm and soil type, and soil dry bulk density. We incorporated the isotope data into the mass balance expression in order to evaluate the performance of CadBal in estimating the past topsoil Cd accumulation and predicting the future concentrations and isotope ratios of Cd (up to 2030 AD). The results of mass balance modelling confirm that recent applications of phosphate fertilisers have not resulted in an accumulation of Cd during the most recent period, thus Cd removal by either leaching or crop uptake has increased, which is consistent with the modelled isotope data (Figure 1). We can conclude that it becomes possible to distinguish the sources of Cd within the soil using stable Cd isotopes (Imseng et al., 2018) and that the residual Cd in topsoil at Winchmore still mainly originates from historical phosphate fertilisers (Salmanzadeh et al., 2017). One implication of this finding is that the contemporary applications of phosphate fertiliser are not resulting in further Cd accumulation. We aim to continue our research into Cd fate, mobility, and transformations in the NZ environment by applying Cd isotopes in soils and aquatic environments across the country. Figure 1. Results of Cd mass balance modelling in CadBal for the period of topsoil fertilisation including a prediction up to the year 2030 AD. (a) Mean concentration of Cd in the dryland treatment of Winchmore long-term irrigation trial (symbols) and the CadBal model (lines) outputs (red symbols = this study- plot 15 of Winchmore site; grey symbols = McDowell study-average of all plots; solid black line = dryland optimized CadBal from McDowell (2012) for all irrigation plots; black dashed line = Plot 15 dryland optimized CadBal-this study, first scenario; blue line = Plot 15 dryland optimized CadBal-this study, second scenario; red line = Plot 15 dryland optimized CadBal-this study, third scenario; red dashed line = Plot 15 dryland optimized CadBal-this study, fourth scenario); (b) Measured and modelled Cd isotope ratios based on CadBal outputs, isotope ratios measured in fertilisers and the fractionation factors of Wiggenhauser, et al. (2016); lines designate modelling scenarios as in (a), red dots are the third scenario with no fractionation (α factor not applied); (c) modeled scenario 3 (solid) and scenario 4 (dashed) isotope ratios in topsoil (red lines), leachate (blue lines) and pasture (green lines)

Soil information systems technology : proceedings of the sixth meeting of the ISSS Working Group on Soil Information Systems, Bolkesjø, Norway, 28 February - 4 March 1983

ISSS congress information system

A Digitális Kreybig talajinformációs rendszer továbbfejlesztésének irányai és eredményei

A Digitális Kreybig talajinformációs rendszer (DKTIR) a mintegy 60 évvel ezelőtti Kreybig-féle talajismereti térképezés adataira épülő, de egyúttal a térinformatika nyújtotta lehetőségeket is kihasználó és a 2010. év elejére országos állománnyá bővült térbeli talajinformációs rendszer. A kialakított térinformatikai adatbázis a felhasználási igények változására reagálva, maga is folyamatosan alakult, lehetővé téve a rugalmasabb és többcélú alkalmazást. Fejlesztésének több iránya van, mely egyrészt az archív adatokat tartalmazó, alapnak tekintett nyers (ún.1K) adatrendszert, másrészt az ebből kiinduló, javított, tematikájában és geometriájában is megújított, integrált (ún. 2K) adatrendszert érinti. Az alap, 1K verzióban folyamatosan zajlik az archív adatok ellenőrzése, valamint az adatbázis építése során, vagy valószínűsíthetően még az eredeti térképezéskor bekerült hibák szűrése. Folyik továbbá az adattári kutatás eredményként előkerült, az eredeti felvételezési módszertantól eltérően készült térképek, illetve mérési adatsorok rendszerbe illesztése. A DKTIR továbbfejlesztésének, a 2K verzió tematikus és térbeli megújításának több iránya van: - a hazai adatrendszerekkel történő korreláltatása; - egy korszerű adat- és információigény kielégítését célzó megfeleltetési rendszer kidolgozása, egy célszerűen választott talajtani paraméter-lista segítségével; - feladat specifikus, digitális talajtérképezési eljárásokban történő többcélú felhasználása; - webes térképi szolgáltatások támogatására az INSPIRE kompatibilitás megteremtése. The Digital Kreybig Soil Information System (DKIS), originally based on the knowledge of Kreybig soil survey performed about 60 years ago, but exploiting the opportunities offered by GIS, became a national soil database at the beginning of 2010. The developed system responses to changing application needs, and evolves continuously, allowing more flexible and multi-purpose applications. There are several direction of its development, which effects on the one hand the raw (K) database, considered as basis with legacy data, and on the other hand, starting form this, the integrated (K) database with improved geometry and renewed thematic content. The basic 1K version is continuously improved by the monitoring of the legacy data and with the filtering of the errors - either generated during the construction of the database or originating from the discrepancies evolved due to the prolonged survey. Furthermore, laboratory data records emerged, which were fitted into the database. There are several directions of the development of DKSIS, the thematic and spatial renewal of its 2K version: - correlations with other national datasets; - elaboration of a compliance system intended to meet the advanced data and information needs based on a suitable soil parameter list; - development its INSPIRE compatibility for web map services

Soil Information System: Web-Based Solution for Agricultural Land-use Planning

The soil-forming factors, especially climate, vegetation and topography, act on a range of rock formations and parent materials leading to the development of different kinds of soils. Through concerted efforts, soil datasets generated earlier are used to develop maps and soil information systems at different scales. Progress in basic and fundamental research on the formation of Indian soils as related to climate, relief, organisms, parent materials and time has helped in developing the soil information system

Evidence-based soils agronomy for raising crop production in Africa

A growing suite of innovative low-cost decision-support tools and soil datasets produced by ICRAF and its partners through the Africa Soil Information Service (AfSIS) and are being used by 14 African governments and other investors to map soil properties and measure crop nutritional responses to different soil management regimes. These technologies are guiding the sustainable restoration of degraded lands and have results in the development of several state-of-the-art national soil information systems (in Ethiopia, Ghana, Nigeria, and Tanzania)

Soil-plant spectral technology guiding soil fertility investments in Africa (WLE-ICRAF)

Seventeen African countries are now using soil–plant spectral technology developed by CGIAR Research Program on Water, Land and Ecosystems (WLE) and partners to restore soils and boost agricultural production. The Africa Soil Information Service (AfSIS) is now being deployed for targeting soil fertility restoration strategies. Ethiopia, Ghana, Nigeria, and Tanzania have established state-of-the-art soil information systems based on the technology. NGOs and the private sector are delivering soil testing services to smallholder farmers and monitor intervention impacts on soil health