The Gallecs trial, a mid-term experiment on reduced tillage, fertilisation and green manure in Mediterranean dryland arable cropping systems

Conservation agriculture and organic farming are two alternative strategies aimed at improving soil fertility in arable cropping systems through reducing tillage intensity, maintaining year-round soil cover and increasing nutrient recycling, using farmyard and green manures. However, the reduction of tillage intensity can increase weed infestation and decrease nutrient availability. The mid-term "Gallecs" trial (Catalonia) was established in autumn 2011 at Gallecs, a periurban agricultural area near Barcelona. The effects of tillage (mouldboard versus chisel ploughing), fertilisation by farmyard manure (without versus with) and green manure (without versus with) on soil fertility indicators, weed abundance and grain crop yields were studied in a 4-years cereal-legume rotation for human consumption under organic farming conditions in the Mediterranean region (Catalonia, Spain)

Molecular Oxygen Lignin Depolymerization: An Insight into the Stability of Phenolic Monomers

This is the peer reviewed version of the following article: Y. Mathieu, J. D. Vidal, L. Arribas Martínez, N. Abad Fernández, S. Iborra, A. Corma, ChemSusChem 2020, 13, 4743, which has been published in final form at https://doi.org/10.1002/cssc.202001295. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] During oxidative depolymn. of lignin in aq. alk. medium using mol. oxygen as oxidant, the highly functionalized primary phenolic monomers are not stable products, owing to various not fully identified secondary reaction mechanisms. However, better understanding of the mechanisms responsible for the instability of the main part of the products of interest derived from lignin is of much interest. Evaluation of their individual reactivities under oxidative conditions should significantly help to find a better way to valorize the lignin polymer and to maximize the yields of target value-added products. Consequently, the main objective of this study is to assess the individual stabilities of some selected ligninbased phenolic compds., such as vanillin, vanillic acid, and acetovanillone, together with some other pure chem. compds. such as phenol and anisole to give an insight into the mechanisms responsible for the simultaneous formation and repolymn. of those products and the influence of the oxidn. conditions. Various complementary strategies of stabilization are proposed, discussed, and applied for the oxidative depolymn. reactions of a tech. lignin extd. from pinewood with a high content of b-O-4 interconnecting bonds to try to obtain enhanced yields of value-added products.The authors thank Tecnicas Reunidas for material and financial support. We also acknowledge the Spanish Ministry of Science, Innovation, and Universities for funding through the "Severo Ochoa" Excellence Program (SEV 2016-0683) and the LIGNO-PRIZED project from the Spanish Centre for the Development of Industrial Technology (CDTI) in the framework of the Strategic Program of National Business Research Consortia (CIEN-2016). Special and kindly thanks are also given to Dr. Dalgi Sunith Barbosa Trillos and Dr. Jakob Mottweiler for their priceless help during the elaboration of the present work.Mathieu, Y.; Vidal, JD.; Arribas Martínez, L.; Abad Fernández, N.; Iborra Chornet, S.; Corma Canós, A. (2020). Molecular Oxygen Lignin Depolymerization: An Insight into the Stability of Phenolic Monomers. ChemSusChem. 13(17):4743-4758. https://doi.org/10.1002/cssc.202001295S474347581317BP. energy outlook2019 https://www.bp.com/content/dam/bp/business-sites/en/global/corporate/pdfs/energy-economics/energy-outlook/bp-energy-outlook-2019.pdf.J. Bluestein J. 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M., & Suresh Kumar, C. (2018). Syringic acid (SA) ‒ A Review of Its Occurrence, Biosynthesis, Pharmacological and Industrial Importance. Biomedicine & Pharmacotherapy, 108, 547-557. doi:10.1016/j.biopha.2018.09.069Baker, C. J., Mock, N. M., Whitaker, B. D., Roberts, D. P., Rice, C. P., Deahl, K. L., & Aver’yanov, A. A. (2005). Involvement of acetosyringone in plant–pathogen recognition. Biochemical and Biophysical Research Communications, 328(1), 130-136. doi:10.1016/j.bbrc.2004.12.153Liu, C., Wu, S., Zhang, H., & Xiao, R. (2019). Catalytic oxidation of lignin to valuable biomass-based platform chemicals: A review. Fuel Processing Technology, 191, 181-201. doi:10.1016/j.fuproc.2019.04.007Levec, J., & Pintar, A. (2007). Catalytic wet-air oxidation processes: A review. Catalysis Today, 124(3-4), 172-184. doi:10.1016/j.cattod.2007.03.035Xiang, Q., & Lee, Y. Y. (2001). Production of Oxychemicals from Precipitated Hardwood Lignin. Applied Biochemistry and Biotechnology, 91-93(1-9), 71-80. doi:10.1385/abab:91-93:1-9:71Santos, S. G., Marques, A. P., Lima, D. L. D., Evtuguin, D. V., & Esteves, V. I. (2010). Kinetics of Eucalypt Lignosulfonate Oxidation to Aromatic Aldehydes by Oxygen in Alkaline Medium. Industrial & Engineering Chemistry Research, 50(1), 291-298. doi:10.1021/ie101402tWu, G., Heitz, M., & Chornet, E. (1994). Improved Alkaline Oxidation Process for the Production of Aldehydes (Vanillin and Syringaldehyde) from Steam-Explosion Hardwood Lignin. Industrial & Engineering Chemistry Research, 33(3), 718-723. doi:10.1021/ie00027a034Bhargava, S., Jani, H., Tardio, J., Akolekar, D., & Hoang, M. (2007). Catalytic Wet Oxidation of Ferulic Acid (A Model Lignin Compound) Using Heterogeneous Copper Catalysts. Industrial & Engineering Chemistry Research, 46(25), 8652-8656. doi:10.1021/ie070085dDeng, H., Lin, L., Sun, Y., Pang, C., Zhuang, J., Ouyang, P., … Liu, S. (2008). Activity and Stability of Perovskite-Type Oxide LaCoO3 Catalyst in Lignin Catalytic Wet Oxidation to Aromatic Aldehydes Process. Energy & Fuels, 23(1), 19-24. doi:10.1021/ef8005349Deng, H., Lin, L., Sun, Y., Pang, C., Zhuang, J., Ouyang, P., … Liu, S. (2008). Perovskite-type Oxide LaMnO3: An Efficient and Recyclable Heterogeneous Catalyst for the Wet Aerobic Oxidation of Lignin to Aromatic Aldehydes. Catalysis Letters, 126(1-2), 106-111. doi:10.1007/s10562-008-9588-0Ansaloni, S., Russo, N., & Pirone, R. (2017). Wet Air Oxidation of Industrial Lignin Case Study: Influence of the Dissolution Pretreatment and Perovskite-type Oxides. Waste and Biomass Valorization, 9(11), 2165-2179. doi:10.1007/s12649-017-9947-4Deng, H., Lin, L., & Liu, S. (2010). Catalysis of Cu-Doped Co-Based Perovskite-Type Oxide in Wet Oxidation of Lignin To Produce Aromatic Aldehydes. Energy & Fuels, 24(9), 4797-4802. doi:10.1021/ef100768eZhang, J., Deng, H., & Lin, L. (2009). Wet Aerobic Oxidation of Lignin into Aromatic Aldehydes Catalysed by a Perovskite-type Oxide: LaFe1-xCuxO3 (x=0, 0.1, 0.2). Molecules, 14(8), 2747-2757. doi:10.3390/molecules14082747Gao, P., Li, C., Wang, H., Wang, X., & Wang, A. (2013). Perovskite hollow nanospheres for the catalytic wet air oxidation of lignin. Chinese Journal of Catalysis, 34(10), 1811-1815. doi:10.1016/s1872-2067(12)60691-3Gale, M., Cai, C. M., & Gilliard‐Abdul‐Aziz, K. L. (2020). Heterogeneous Catalyst Design Principles for the Conversion of Lignin into High‐Value Commodity Fuels and Chemicals. ChemSusChem, 13(8), 1947-1966. doi:10.1002/cssc.202000002Pepper, J. M., Baylis, P. E. T., & Adler, E. (1959). THE ISOLATION AND PROPERTIES OF LIGNINS OBTAINED BY THE ACIDOLYSIS OF SPRUCE AND ASPEN WOODS IN DIOXANE–WATER MEDIUM. Canadian Journal of Chemistry, 37(8), 1241-1248. doi:10.1139/v59-183Yuan, T.-Q., Sun, S.-N., Xu, F., & Sun, R.-C. (2011). Characterization of Lignin Structures and Lignin–Carbohydrate Complex (LCC) Linkages by Quantitative 13C and 2D HSQC NMR Spectroscopy. Journal of Agricultural and Food Chemistry, 59(19), 10604-10614. doi:10.1021/jf2031549Bauer, S., Sorek, H., Mitchell, V. D., Ibáñez, A. B., & Wemmer, D. E. (2012). Characterization of Miscanthus giganteus Lignin Isolated by Ethanol Organosolv Process under Reflux Condition. Journal of Agricultural and Food Chemistry, 60(33), 8203-8212. doi:10.1021/jf302409dWen, J.-L., Sun, S.-L., Xue, B.-L., & Sun, R.-C. (2013). Recent Advances in Characterization of Lignin Polymer by Solution-State Nuclear Magnetic Resonance (NMR) Methodology. Materials, 6(1), 359-391. doi:10.3390/ma6010359Peterson, D. J., & Loening, N. M. (2007). QQ-HSQC: a quick, quantitative heteronuclear correlation experiment for NMR spectroscopy. Magnetic Resonance in Chemistry, 45(11), 937-941. doi:10.1002/mrc.2073Sette, M., Wechselberger, R., & Crestini, C. (2011). Elucidation of Lignin Structure by Quantitative 2D NMR. Chemistry - A European Journal, 17(34), 9529-9535. doi:10.1002/chem.201003045Tarabanko, V. E., Petukhov, D. V., & Selyutin, G. E. (2004). New Mechanism for the Catalytic Oxidation of Lignin to Vanillin. Kinetics and Catalysis, 45(4), 569-577. doi:10.1023/b:kica.0000038087.95130.a5Rinesch, T., Mottweiler, J., Puche, M., Concepción, P., Corma, A., & Bolm, C. (2017). Mechanistic Investigation of the Catalyzed Cleavage for the Lignin β-O-4 Linkage: Implications for Vanillin and Vanillic Acid Formation. ACS Sustainable Chemistry & Engineering, 5(11), 9818-9825. doi:10.1021/acssuschemeng.7b01725Sette, M., Lange, H., & Crestini, C. (2013). QUANTITATIVE HSQC ANALYSES OF LIGNIN: A PRACTICAL COMPARISON. Computational and Structural Biotechnology Journal, 6(7), e201303016. doi:10.5936/csbj.201303016Bujanovic, B., Ralph, S., Reiner, R., Hirth, K., & Atalla, R. (2010). 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Impacts of Use and Abuse of Nature in Catalonia with Proposals for Sustainable Management

This paper provides an overview of the last 40 years of use, and in many cases abuse, of the natural resources in Catalonia, a country that is representative of European countries in general, and especially those in the Mediterranean region. It analyses the use of natural resources made by mining, agriculture, livestock, logging, fishing, nature tourism, and energy production and consumption. This use results in an ecological footprint, i.e., the productive land and sea surface required to generate the consumed resources and absorb the resulting waste, which is about seven times the amount available, a very high number but very similar to other European countries. This overexploitation of natural resources has a huge impact on land and its different forms of cover, air, and water. For the last 25 years, forests and urban areas have each gained almost 3% more of the territory at the expense of agricultural land; those municipalities bordering the sea have increased their number of inhabitants and activity, and although they only occupy 6.7% of the total surface area, they account for 43.3% of the population; air quality has stabilized since the turn of the century, and there has been some improvement in the state of aquatic ecosystems, but still only 36% are in good condition, while the remainder have suffered morphological changes and different forms of nonpoint source pollution; meanwhile the biodiversity of flora and fauna remains still under threat. Environmental policies do not go far enough so there is a need for revision of the legislation related to environmental impact and the protection of natural areas, flora, and fauna. The promotion of environmental research must be accompanied by environmental education to foster a society which is Land 2021, 10, 144 3 of 53 more knowledgeable, has more control and influence over the decisions that deeply affect it. Indeed, nature conservation goes hand in hand with other social and economic challenges that require a more sustainable vision. Today’s problems with nature derive from the current economic model, which is environmentally unsustainable in that it does not take into account environmental impacts. Lastly, we propose a series of reasonable and feasible priority measures and actions related to each use made of the country’s natural resources, to the impacts they have had, and to their management, in the hope that these can contribute to improving the conservation and management of the environment and biodiversity and move towards sustainability.info:eu-repo/semantics/publishedVersio

La fertilisation en pépinière affecte la tolérance au froid et la qualité des plants bouturés d’Eucalyptus globulus Labill

International audienc

Productivity of Pinus radiata plantations in Spain in response to climate and soil

Abstract Pinus radiata D. Don is planted in Spain, in a wide range of soils and climatic conditions. We aimed to identify the main site factors that control the productivity of this species and determine to what extent its growth is limited by the soil quality and the climate. For this purpose, we selected 22 stands of P. radiata on the basis of parent material (nine substrates) and climate (Mediterranean and Atlantic). The highest levels of forest productivity were unexpectedly found in the lower rainfall Mediterranean area, while the lowest ones were found in the wet Atlantic area. Litterfall showed the highest correlation with site index. Soil depth combined with altitude was also significantly related to site index. Principal component analysis, performed using a set of selected soil and site fertility variables, showed a separation between the Atlantic and the Mediterranean sites, suggesting that the soil processes determining soil fertility differ in the two climates. Within each climatic zone, site environmental variables were clearly associated with site index. In the Mediterranean area, site index was strongly related to soil depth and to the amount of P in the organic layers, while in the Atlantic area it was mainly associated with site altitude and mineral soil CEC. According to our results, Mediterranean plantations are confined to deep soils and their quality is also related to the amount and concentration of nutrients in the organic layers. On the other hand, the Atlantic plantations grow faster at lower elevations and they are also sensitive to soil fertility as their site quality is affected by CEC. The intensive management of these plantations is likely to increase productivity mainly in areas not limited by temperature.

Sampling strategies in forest soils

Many studies have revealed the high variability of soil properties, especially on the forest floor. Sampling techniques have been developed to reduce this variability so as to obtain more precise mean values. Little attention has been paid to the frequency distributions of variables, even though they could provide information on factors that control variability. This paper addresses the selection of the sampling strategy considering the type of study. For the characterization of ecosystems, stratified sampling or systematic sampling is proposed, depending on previous knowledge of the study area. To study processes, two cases were considered: processes that occur within the ecosystem, such as organic matter decomposition, and processes that concern the whole ecosystem, such as fire. In the first case subjective sampling was useful, since it reduced the extrinsic variability of the processes. In the second case, both stratified and systematic sampling were very effective. Frequency distribution analysis was proposed as a tool to detect some factors that control litter accumulation.Stratégies d'échantillonnage dans les sols forestiers. Beaucoup d'études ont révélé la grande variabilité des propriétés du sol, en particulier celles relatives aux horizons organiques. Plusieurs techniques d'échantillonnage ont été développées pour réduire la variabilité et obtenir des valeurs moyennes avec précision. Bien que l'étude des distributions de fréquences puisse fournir des informations sur les facteurs qui contrôlent la variabilité, cette approche a reçu peu d'attention. Cet article discute la sélection de stratégies d'échantillonnage selon le type d'étude à effectuer. Pour la caractérisation des écosystèmes on a proposé l'échantillonnage stratifié ou l'échnntillonnage systématique. Le choix de l'un ou de l'autre dépend de l'information disponible sur l'aire d'étude. Pour l'étude de processus, deux cas ont été considérés : les processus à l'intérieur de l'écosystème (décomposition de la matière organique) et les processus qui affectent tout l'écosystème (le feu). Dans le premier cas, l'échantillonnage dirigé s'est montré approprié parce qu'il réduit la variabilité extrinsèque au processus. Dans le second cas, les deux techniques d'échantillonnage (stratifié et systématique) ont été efficaces. L'analyse de la distribution des fréquences a été jugée utile pour détecter les facteurs qui contrôlent l'accumulation de la litière

C sequestration issues in the Mediterranean soils

The Mediterranean region has distinct characteristics resulting from its climate, land use history and landforms that may largely affect soil C balances. In this paper we present data on C storage in Mediterranean soils and how it can be affected by changes in land use and fire. We also discuss the sensitivity of organic matter levels in Mediterranean soils to land use and management in order to set the basis for increasing C sequestration in the Mediterranean

Factors regulating carbon mineralization in the surface and subsurface soils of Pyrenean mountain grasslands

8 páginas, 3 tablas, 4 figuras.Although a large amount of soilcarbon (C) is stored in subsurfacesoils, most studies on soil C dynamics focus on the upper layers. The aim of this study is to assess the factors that regulate C mineralization in mountaingrasslandsoils under standard laboratory conditions to compare regulation mechanisms at surface and subsurface horizons. For this purpose soil samples of surface and subsurface horizons from 35 locations were incubated under laboratory conditions, CO2 efflux rates were measured and microbial biomass C (MBC) and net N mineralization were determined. We also analysed the samples for pH, extractable C after fumigation (Cfe), potentially mineralizable N (PMN), reactive and non-reactive P, sum of exchangeable bases and clay content in order to assess the influence of soil characteristics on C mineralization. The influence of climate of each site on soil C mineralization under the same laboratory conditions was also explored for surface and subsurface horizons. C mineralization in surface horizons related positively with Cfe content, suggesting that microbial activity in this horizon was mainly regulated by the availability of C. By contrast, in subsurface horizons, C mineralization related with PMN and was independent of measured C fractions, suggesting that microbial activity in subsurface horizons was limited by the availability of N and that the available forms of C were more stable in these horizons. The effects of local climate on laboratory C mineralization were significant in both soil horizons, with lower rates of C mineralization being recorded in soils from wetter and warmer sites. This fact, suggested that the C stabilisation mechanisms in mountaingrasslandsoils may be affected by the climate in which soils develop.This study was partially funded by the European Commission (EMERGE and CarboEurope-IP projects), by the Spanish Ministry of Science and Education (CARBOPAS and Agroeco projects) and INIA (Balangeis project). CEAM is financially supported by Generalitat Valenciana and Bancaixa. This study is a result of the activities of the Pyrenean Limnological Observatory of Global Change, a joint initiative of the Center for Advanced Studies-CSIC and the Center for High Mountain Research, University of Barcelona.Peer reviewe

Soil organic carbon storage in mountain grasslands of the Pyrenees: effects of climate and topography

11 páginas, 4 figuras, 4 tablas.The prediction of soil C stocks across the landscape has been increasingly studied in many areas of the world. Soil organic C storage in mountain areas is highly heterogeneous, mainly as a result of local-scale variability in the soil environment (topography, stoniness, parent material) and microclimate. The aims of the present study are to estimate soil organic C stocks (SOCS) in mineral soils of high-altitude grasslands of the Pyrenees and determine whether climatic and topographic variables can be used as predictors of SOCS and organic C content in the surface soil horizons of these ecosystems. For that purpose we sampled 35 soil profiles in subalpine and alpine grasslands including a range of altitudes, slopes and aspects. We analysed the soils for stoniness, bulk density, total C, texture, and C-to-N ratio and determined topographical variables. We used georeferenced climatic information for climatic descriptions of the sites. SOCS were highly correlated with soil depth. However, we were not able to predict soil depth by using environmental and topographic variables. In spite of this fact, altitude and aspect explained 41.2% of the SOCS variability while summer temperature and precipitation combined with aspect explained 56.9% of the variability of the organic C content of the surface layer (OC). The SOCS were low at high altitudes, probably as a result of an overall temperature limitation of net primary productivity. Under these conditions, the effect of aspect was small. The highest SOCS occurred at the lowest altitudes for ENE or WNW aspects, showing sharper decreases towards the south than to the north. The harsh climatic conditions and low-plant productivity that occur at the northern slopes reduced SOCS at the highest altitudes. In contrast, southern aspects showed similar organic C content along the altitudinal gradient. The OC variability in the surface soils not explained by climatic or topographic variables was partially related to the characteristics of soil organic matter, which may depend on the plant communities.This work was funded in part by the European Commission under the EMERGE (EVK1-CT- 1999-00032) and CARBOMONT (EVK2-CT-2001-00125) projects, by the Spanish Ministry of Science and Technology under the CARBOPAS (REN2002-04300- C02-02) project and the Spanish Interministerial Committee on Science and Technology (grant REN2000- 0889/GLO).Peer reviewe