Impact of long-term compost addition on trace metal behaviour in agricultural soils
Naziv natječaja: Program integriranih akcija „Cogito"
Izvor financiranja: MZO
Uloga AFZ: koordinator
Ukupna vrijednost: 2 540,00 EUR
Financirani iznos: 2 540,00 EUR
Početak provedbe: 01.01.2017.
Završetak provedbe: 31.12.2018.
The application of soil organic amendments is known to alter soil physical properties, for example, by reducing bulk density, increasing infiltration rate and hydraulic conductivity, increasing water retention, and enhancing aggregate stability (e.g., Kranz et al., 2020; Razzaghi et al., 2020). In turn, this supports improvements in plant growth (Sun et al., 2014; Yu et al., 2019). Plant agricultural production primarily takes place in soil critical (vadose) zone, referring to the part of the soil between the soil surface and groundwater in which the pore space between the soil particles is filled with water and air (Nimmo, 2009). Soil critical zone is one of the most complex terrestrial systems due to a wide range of processes occurring within its boundaries. Under conditions of intensive agricultural production, a substantial amount of fertilizers and pest control products are commonly used to ensure high and stable yields. Most of these agrochemicals (nitrate, phosphorus, trace elements, pesticides) are prone to leaching below the root zone and may be transported to groundwater resources. Tropical and subtropical soils are affected by long intense weathering (Van Wambeke, 1992), including Nitisols which are found on about 200 million ha worldwide, especially in tropical Africa (IUSS Working Group WRB, 2015). They are more productive than other tropical soils, mainly due to some good chemical and physical properties, including a stable soil structure and deep and porous sola. This type of soil ad often intensively cultivated as in some regions they present a valuable resource, particularly on islands where the land area associated to food production is limited. At the same time organic and mineral fertilizers are necessary to maintain the soil fertility, but the application of such compounds represents a significant risk of environmental pollution. Recently, Evans et al., (2019) pointed out the need for better understanding of water management in agricultural areas and water pollution issue originating from agricultural activities, including development of accurate methods for quantifying pollution sources. Most fertilizers commonly applied in agriculture include some type of nitrogen (N) source, which, if leached, may be negatively reflected on a nearby surface and groundwater quality. Subject related studies report that about a third of water bodies across Europe exceed the guideline values for nitrate concentration, recognized as one of the major risks in decreasing water quality (European Commission, 2008). One possible risk for nitrate leaching originates from the application of quick-release N fertilizers at high rates, followed by periods of high precipitation or under excessive irrigation (e.g., Filipović et al., 2014). The main processes governing the leaching of alt above-mentioned agrochemicals are advection, dispersion, sorption and degradation, which can be the accurately estimated by combining field observations, laboratory methods and numerical modeling. However, throughout the Europe there is a lack in long-term field observatories that provide reliable data on different processes in soil vadose zone. Fortunately, France is one of the countries that saw the importance of having these long-term observatories early on and established a network of sites SOERE PRO (https://www6.inrae.fr/qualiaqro eng/Nos-partenaires/The-SOERE-PRO-network). Each of the obseNatories have specific objective. The proposed project will be focused on long-term site at REUNION island. The objective of SOERE PRO Reunion experimental site is to characterize the agronomic value and environmental impacts of i) sludge, ii) composted sludge, iii) pig manure, iv) poultry litter and v) mineral fertilizer. The COGITO project will focus on quantifying dynamic hydraulic and transport properties that could have important environmental impact. The complementary groups will expand the data at hand using novel laboratory techniques and state of the art numerical modeling. SOERE-PRO experimental site at Reunion island is a long-term field study started in 2014 on 1.2 ha with 6 treatments (5 replicates). The site is divided on 30 plots (180 m? each) with weather station. It should be noted that the weather condition implies around 2000 mm (e.g., Feder et al., 2015), so the leaching potential of applied nutrients is massive. The site is instrumented with sensors for soil water content (T DR) and soil water potential measurements (T4e tensiometers) with 20 cm in depth spatial resolution. All the modalities of the block 2 are equipped with a meter lysimetric glass fiber; leachates are collected in the glass flasks in manholes and are regularly sampled for analysis. Detailed physical and chemical soil properties are determined as well. However, the site is lacking in-depth analysis of soil hydraulic properties (SHPs) which are governing solute transport (e.g., nitrates). On Croatian side the team have necessary equipment for elaborate SHP determination and soil water retention curve estimation (Ksat, HYPROP and WP4C, Meter Group US). This is provided within the SUPREHILL project, a first Critical Zone Observatory in Croatia started in 2020. The samples from Reunion island will be delivered to University of Zagreb and the Croatian team will determine necessary parameters. The next step will be focused on numerical modeling study on profile or plot scale (e.g., ID or 2D). The modeling should answer and quantify water flow in such soils and potential solute (e.g., nitrate leaching) base on the data from installed lysimeters. It should be noted that a limited number of transport studies has been done on tropical soils. The project will be performed in collaboration with CIRAD (https://ur-recyclaqerisque.cirad.fr/en/main-proiects/soere-pro-la-reunion) under the SOERE PRO network and University of Zagreb Faculty of Agriculture (http://www.agr.unizg.hr/en) with the team of SUPREHILL project (https://sites.aooqle.com/view/suprehill/). The collaboration should expand the current understanding on vadose zone processes and connect active research groups focusing on Critical Zone Observatories (CZO). Funding should enable groups to visit CZO sites collect necessary data, expand the research aims of each site and produce novel scientific publications. At both sites, the principal investigators (Dr. Frédéric Feder and Dr. Vilim Filipović) will have talks for scientific staff and students.
prof. dr. sc. Philippe Cambier
UMR ECOSYS, INRA, AGROParisTech, Sveučilište ParisSaclay, Thiverval-Grignon
izv. prof. dr. sc. Vilim Filipović
Sveučilište u Zagrebu Agronomski fakultet