Mapping the storing and filtering capacity of European soils

The purpose of the current study was to develop an estimation method based on available soil map information (categorical data) and thereafter estimate and map across Europe the soil filtering and storing capacity of different substances, which support ecosystem services and those which present a hazard to the ecosystem functioning. Pollutants were grouped as follows: (1) elements in cationic form; (2) elements in anionic form; (3) solids and pathogenic microorganisms; (4) non-polar organic chemicals and (5) nonaqueous phase liquids (NAPLs). The spatial pattern of areas with high soil storing capacity are largely different depending on the stored substances. In general, those soils are characterized by good storing capability that have thick topsoil and subsoil layers and these layers are free from the effects of groundwater. As the content of clay and humus content increases and the stone or gravel content decreases, the storage capacity increases simultaneously. However, the effect of soil pH and the soil mineralogy is different depending on the various groups of pollutants (e.g. the calcareous soils with high swelling clay mineral content are able to bind more cations, whereas the acidic soils or the soils with high sesquioxide content have higher anion storing capacity). The soil filtering capacity pattern of Europe in the case of different groups of substances are in part similar to the storing capacity pattern. The main difference between the two parameters was to take account of infiltration rate and the thickness of the filtration path up to the groundwater during the filtering capacity estimation.JRC.D.3-Land Resource

Incipient ferralization and weathering indices along a soil chronosequence in Taiwan

The low hilly topography of Green Island, a volcanic island off southeastern Taiwan, includes an altitudinal sequence of sub-horizontal benches. We examined eight profiles along this sequence, ranging from pale brown loamy coral sand on the lowest bench that fringes the coast at an elevation of about 10 m to deep, intensely red and acid clay on the highest bench at about 240 m. Chemical analyses, differential Fe extractions, thin sections, X-ray diffraction of the clay minerals and indices of pedochemical weathering and strain indicated that soil development progressed by weathering of primary and secondary phyllosilicates through argilluviation in the intermediate stages to the generation of increasing quantities of free Fe. The Fe accumulates as free sesquioxides, which crystallize with age. Taxonomically the soil types progress from sandy coral Arenosol, through Eutric Cambisol, Hypereutric Lixisol and Acrisol to incipient Ferralsol (Udipsamment → Eutrudept → Udalf → Udultisol → Udox in Soil Taxonomy). The profiles are interpreted as a chronosequence, although this is complicated by minor and upwardly diminishing contributions of reef coral to the mainly igneous parent materials. There are also variations in the andesitic-basaltic bedrock, and minor aeolian inputs in the higher and older soil types. Regional eustatic sea-level correlations, 14C dating of carbonates on the two lowest benches and estimates of local tectonic uplift indicate that the incipient Ferralsols on the upper bench might date from about 150 ka. The transition through argilluvial Acrisols to incipient sesquioxide-dominated Ferralsols appears, therefore, to develop within 100–200 ka on Green Island, which is faster than usual

Physically-based modelling of hydrological processes in a tropical headwater catchment (West Africa) ? process representation and multi-criteria validation

International audienceThe aim of the study was to test the applicability of a physically-based model to simulate the hydrological processes in a headwater catchment in Benin. Field investigations in the catchment have shown that lateral processes such as surface runoff and interflow are most important. Therefore, the 1-D SVAT-model SIMULAT was modified to a semi-distributed hillslope version (SIMULAT-H). Based on a good database, the model was evaluated in a multi-criteria validation using discharge, discharge components and soil moisture data. For the validation of discharge, good results were achieved for dry and wet years. The main differences were observable in the beginning of the rainy season. A comparison of the discharge components determined by hydro-chemical measurements with the simulation revealed that the model simulated the ratio of groundwater fluxes and fast runoff components correctly. For the validation of the discharge components of single events, larger differences were observable, which was partly caused by uncertainties in the precipitation data. The representation of the soil moisture dynamics by the model was good for the top soil layer. For deeper soil horizons, which are characterized by higher gravel content, the differences between simulated and measured soil moisture were larger. A good agreement of simulation results and field investigations was achieved for the runoff generation processes. Interflow is the predominant process on the upper and the middle slopes, while at the bottom of the hillslope groundwater recharge and ? during the rainy season ? saturated overland flow are important processes

Rice Intensification in a Changing Environment: Impact on Water Availability in Inland Valley Landscapes in Benin

This study assesses the impact of climate change on hydrological processes under rice intensification in three headwater inland valley watersheds characterized by different land conditions. The Soil and Water Assessment Tool was used to simulate the combined impacts of two land use scenarios defined as converting 25% and 75% of lowland savannah into rice cultivation, and two climate scenarios (A1B and B1) of the Intergovernmental Panel on Climate Change Special Report on Emissions Scenarios. The simulations were performed based on the traditional and the rainfed-bunded rice cultivation systems and analyzed up to the year 2049 with a special focus on the period of 2030–2049. Compared to land use, climate change impact on hydrological processes was overwhelming at all watersheds. The watersheds with a high portion of cultivated areas are more sensitive to changes in climate resulting in a decrease of water yield of up to 50% (145 mm). Bunded fields cause a rise in surface runoff projected to be up to 28% (18 mm) in their lowlands, while processes were insignificantly affected at the vegetation dominated-watershed. Analyzing three watersheds instead of one as is usually done provides further insight into the natural variability and therefore gives more evidence of possible future processes and management strategie

Modificaciones químicas inducidas por dos especies de lombrices geófagas en suelos de Veracruz, México.

Dos lombrices tropicales, una exótica (Pontoscolex corethrurus) y otra nativa (Glossoscolecidae sp.) de Veracruz, México, fueron cultivadas en condiciones de laboratorio para colectar sus respectivos turrículos (deyecciones) cada 48 horas, medir su tasa de producción y el efecto que ejercen sobre varios parámetros químicos en el suelo excretado. Ambas especies fueron cultivadas en un Lixisol (La Víbora) y P. corethrurus lo fue también en otros dos tipos de suelo, un Vertisol (Plan de las Hayas) y un Andosol (Los Tuxtlas). Los parámetros químicos medidos en los turrículos y en suelo testigo (control) fueron los siguientes: pH, C, N, C/N, NO3, NH4, Na, K, Ca, Mg, CIC, P-asimilable, P-Total, P-Resinas, Al, Fe, Cu, Zn, Mn. Para P. corethrurus la producción de turrículos superficiales fue más alta en los suelos con menor contenido de MO. En el Lixisol, Glossoscolecidae sp. produjo menor cantidad de turrículos comparada con P. corethrurus, pero promovió una disponibilidad mayor, especialmente de K, Na Mg, Mn, Fe, K y NH4. Pontoscolex corethrurus promovió también la concentración de la mayor parte de los parámetros estudiados con respecto al suelo control, tanto en el Andosol como en el Vertisol; en el Lixisol, esta especie incrementó la concentración en la mitad de los parámetros. Pontoscolex corethrurus tiene una capacidad alta de adaptarse a diferentes suelos y de modificar sus características químicas, promoviendo la disponibilidad de diversos elementos esenciales para el crecimiento vegetal; eso es especialmente importante en los suelos más pobres como el Lixisol

Soil Geographical Database of Eurasia and the Mediterranean: Instructions Guide for Elaboration at Scale 1:1,000,000

Abstract not availableJRC.H-Institute for environment and sustainability (Ispra

Gérer les parcs à Faidherbia albida pour la production de bois. Quelles potentialités dans le quartier de Sirlawe I, pays tupuri, Cameroun? : étude réalisée du 8 au 27 février 2004

Comme la plupart des villages du pays Tupuri dans la province de l'Extrême-Nord camerounais, le terroir densément peuplé de Sirlawé connaît une pénurie de bois de feu liée à la raréfaction des ressources arborées périphériques et à la protection officielle de la principale essence de son parc arboré, Faidherbia albida Del. A. Chev.. Afin de combler cette pénurie, la définition de règles d'accès à la ressource existante et de densification du parc arboré a été initiée sur la base de (1) la caractérisation de la structure du parc agroforestier du quartier de Sirlawé I grâce à une cartographie de l'espace villageois (à dire d'acteur et par lever) et un inventaire systématique, (2) la quantification de sa productivité potentielle par émondage sur la base d'un modèle de prédiction de biomasse construit localement, et (3) d'enquêtes auprès d'usagers de la ressource. En plus d'une zone de parcours partagée avec d'autres terroirs l'étude a confirmé l'existence de trois grands espaces fréquemment identifiés dans un finage Tupuri: (1) les champs de case à vocation céréalière sous parc vieillissant à Faidherbia albida, (2) une auréole de brousse vouée aux cultures peu intensifiées vivrières et de rente, faiblement arborée mais siège d'une expansion du parc, et (3) une zone de bas fond sans arbres dédiée au sorgho de contre-saison. La biomasse disponible de Faidherbia albida exploitable par émondage sur l'ensemble du parc du quartier a été estimée à 1830 t de matière sèche (MS) soit 3,97 tMS ha* En plus de couvrir les besoins de la population pour les quatre années à venir, elle participerait à la revitalisation nécessaire d'un parc vieillissant. L'étude fait des propositions pour un cadre d'exploitation de cette ressource "dormante" sur des bases viables négocié entre villageois, autorités officielles et coutumières. Un système original de tontine "inversée" permettant aux habitants de partager, sur une base démonétisée, le produit d'un émondage progressif pourrait être mis en place. Cet émondage, planifié selon des modèles de productivité qui restent à définir, serait accordé en contrepartie d'engagements de densification, d'expansion et de diversification du parc existant, par plantation ou protection des drageons ou semences naturelles. (Résumé d'auteur

The role of cattle manure in enhancing on-farm productivity, macro- and micro-nutrient uptake, and profitability of maize in the Guinea savanna

An on-farm trial was conducted in the northern Guinea savanna of Nigeria, over a period of five years, with the objectives of quantifying the effects on maize of applying cattle manure in combination with synthetic fertilizer with regard to soil characteristics, yield, plant nutrition and profitability. Maize grain yield was significantly increased by the annual application of cattle manure, compared to maize receiving an equal amount of N through synthetic fertilizer, but only from the third year of the experiment. The application of manure resulted in higher soil Kjel N, Bray-I P and exchangeable K values, and an increased N utilization efficiency by maize, suggesting that yield-limiting factors other than N deficiencies were of lesser importance than in the treatment receiving sole inorganic fertilizer. Nutrients other than N applied via the manure, particularly P, K and/or B, may have contributed to the higher grain yields in treatments receiving manure. A partial budgeting analysis revealed that, over a 5-year period, investments in the application of manure, in combination with synthetic fertilizer, resulted in higher margins than the application of fertilizer alone. However, analyses of marginal rates of return of changes from low urea N to high urea N or additional manure applications suggested that it was more profitable to invest in additional urea than in organic manure in the first two years of the experiment. The results suggested that manure applications, even when applied at relatively high rates, did not serve as a quick fix to on-farm soil fertility problems, but over a longer period, manure applied in combination with synthetic fertilizers did provide a significant and profitable contribution to enhanced cereal production