Guillaume, Thomas

[["dc.bibliographiccitation.firstpage","49"],["dc.bibliographiccitation.journal","Ecological Indicators"],["dc.bibliographiccitation.lastpage","57"],["dc.bibliographiccitation.volume","67"],["dc.contributor.author","Guillaume, Thomas"],["dc.contributor.author","Maranguit, Deejay"],["dc.contributor.author","Murtilaksono, Kukuh"],["dc.contributor.author","Kuzyakov, Yakov"],["dc.date.accessioned","2018-11-07T10:10:33Z"],["dc.date.available","2018-11-07T10:10:33Z"],["dc.date.issued","2016"],["dc.description.abstract","Tropical forest conversion to agricultural land leads to a strong decrease of soil organic carbon (SOC) stocks. While the decrease of the soil C sequestration function is easy to measure, the impacts of SOC losses on soil fertility remain unclear. Especially the assessment of the sensitivity of other fertility indicators as related to ecosystem services suffers from a lack of clear methodology. We developed a new approach to assess the sensitivity of soil fertility indicators and tested it on biological and chemical soil properties affected by rainforest conversion to plantations. The approach is based on (non-)linear regressions between SOC losses and fertility indicators normalized to their level in a natural ecosystem. Biotic indicators (basal respiration, microbial biomass, acid phosphatase), labile SOC pools (dissolved organic carbon and light fraction) and nutrients (total N and available P) were measured in Ah horizons from rainforests, jungle rubber, rubber (Hevea brasiliensis) and oil palm (Elaeis guineensis) plantations located on Sumatra. The negative impact of land-use changes on all measured indicators increased in the following sequence: forest < jungle rubber < rubber < oil palm. The basal respiration, microbial biomass and nutrients were resistant to SOC losses, whereas the light fraction was lost stronger than SOC. Microbial C use efficiency was independent on land use. The resistance of C availability for microorganisms to SOC losses suggests that a decrease of SOC quality was partly compensated by litter input and a relative enrichment by nutrients. However, the relationship between the basal respiration and SOC was non-linear; i.e. negative impact on microbial activity strongly increased with SOC losses. Therefore, a small decrease of C content under oil palm compared to rubber plantations yielded a strong drop in microbial activity. Consequently, management practices mitigating SOC losses in oil palm plantations would strongly increase soil fertility and ecosystem stability. We conclude that the new approach enables quantitatively assessing the sensitivity and resistance of diverse soil functions to land-use changes and can thus be used to assess resilience of agroecosystems with various use intensities. (C) 2016 Elsevier Ltd. All rights reserved."],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft (DFG) [CRC990]"],["dc.identifier.doi","10.1016/j.ecolind.2016.02.039"],["dc.identifier.isi","000388785300006"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/39877"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.relation","SFB 990: Ökologische und sozioökonomische Funktionen tropischer Tieflandregenwald-Transformationssysteme (Sumatra, Indonesien)"],["dc.relation","SFB 990 | A | A04: Carbon stock, turnover and functions in heavily weathered soils under lowland rainforest transformation systems"],["dc.relation.issn","1872-7034"],["dc.relation.issn","1470-160X"],["dc.subject.gro","sfb990_journalarticles"],["dc.title","Sensitivity and resistance of soil fertility indicators to land-use changes: New concept and examples from conversion of Indonesian rainforest to plantations"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","385"],["dc.bibliographiccitation.journal","CATENA"],["dc.bibliographiccitation.lastpage","393"],["dc.bibliographiccitation.volume","149"],["dc.contributor.author","Maranguit, Deejay"],["dc.contributor.author","Guillaume, Thomas"],["dc.contributor.author","Kuzyakov, Yakov"],["dc.date.accessioned","2018-11-07T10:28:12Z"],["dc.date.available","2018-11-07T10:28:12Z"],["dc.date.issued","2017"],["dc.description.abstract","Deforestation and land-use change in tropics have increased over the past decades, driven by the demand for agricultural products. Although phosphorus (P) is one of the main limiting nutrients for agricultural productivity in the tropics, the effect of land-use change on P availability remains unclear. The objective was to assess the impacts of land-use change on soil inorganic and organic P fractions of different availability (Hedley sequential fractionation) and on P stocks in highly weathered tropical soils. We compared the P availability under extensive land-use (rubber agroforest) and intensive land-use with moderate fertilization (rubber monoculture plantations) or high fertilization (oil palm monoculture plantations) in Indonesia. The P stock was dominated by inorganic forms (60 to 85%) in all land-use types. Fertilizer application increased easily-available inorganic P (i.e., H2O-Pi, NaHCO3-Pi) in intensive rubber and oil palm plantations compared to rubber agroforest However, the easily-available organic P (NaHCO3-extractable Po) was reduced by half under oil palm and rubber. The decrease of moderately available and non-available P in monoculture plantation means that fertilization maintains only the short-term soil fertility that is not sustainable in the long run due to the depletion of P reserves. The mechanisms of this P reserve depletion are: 1) soil erosion (here assessed by C/P ratio), 2) mineralization of soil organic matter (SOM) and 3) P export with yield products. Easily-available P fractions (i.e., H2O-Pi, NaHCO3-Pi and Po) and total organic P were strongly positively correlated with carbon content, suggesting that SOM plays a key role in maintaining P availability. Ecologically based management is therefore necessary to mitigate SOM losses and thus increase the sustainability of agricultural production in P-limited, highly weathered tropical soils. (C) 2016 Elsevier B.V. All rights reserved."],["dc.identifier.doi","10.1016/j.catena.2016.10.010"],["dc.identifier.isi","000390733300038"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/43373"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation","SFB 990: Ökologische und sozioökonomische Funktionen tropischer Tieflandregenwald-Transformationssysteme (Sumatra, Indonesien)"],["dc.relation","SFB 990 | A | A04: Carbon stock, turnover and functions in heavily weathered soils under lowland rainforest transformation systems"],["dc.relation.issn","1872-6887"],["dc.relation.issn","0341-8162"],["dc.subject.gro","sfb990_journalarticles"],["dc.title","Land-use change affects phosphorus fractions in highly weathered tropical soils"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","110"],["dc.bibliographiccitation.journal","Agriculture, Ecosystems & Environment"],["dc.bibliographiccitation.lastpage","118"],["dc.bibliographiccitation.volume","232"],["dc.contributor.author","Guillaume, Thomas"],["dc.contributor.author","Holtkamp, Anna Mareike"],["dc.contributor.author","Damris, Muhammad"],["dc.contributor.author","Brümmer, Bernhard"],["dc.contributor.author","Kuzyakov, Yakov"],["dc.date.accessioned","2017-11-28T10:02:28Z"],["dc.date.available","2017-11-28T10:02:28Z"],["dc.date.issued","2016"],["dc.description.abstract","Tropical regions, such as Sumatra, experiencing extensive transformation of natural ecosystems, are close to complete exhaustion of available land. Agroecosystems strongly modify water and nutrient cycles, leading to losses of soil fertility, C sequestration and biodiversity. Although large companies are the main drivers of deforestation and plantation establishment, smallholders account for 40% of the oil palm and the majority of the rubber production in Indonesia. Here, we assess the extent and mechanisms of soil degradation under smallholder oil palm and rubber plantations in a context of land scarcity. The topsoil properties (C and N contents, C stocks, C/N ratio, bulk density) in 207 oil palm and rubber plantations in the Jambi province of Sumatra were determined beside trees, inside rows and interrows. Soils under oil palms were on average more degraded than under rubber, showing lower C content and stocks, lower N and higher bulk density. While soil properties were homogenous under rubber, two opposite trends were observed under oil palm plantations: the majority of soils had C content <2.2%, but about one fifth of the plantations had >9% C. This resulted from the establishment of oil palms under conditions of land scarcity. Because the oil palm boom started when rubber was already well-established, oil palms were frequently planted in marginal areas, such as peatlands or riparian areas (high C) or soils degraded by previous use (low C). The management of oil palms led to subsequent soil degradation, especially in interrows: C content decreased and bulk density increased in older oil palm plantations. This was not observed in rubber plantations because of a C input from leaf litter spread homogeneously all over the plantation, higher ground cover and a limited use of motorized vehicles. Considering that 10% of soils under oil palms had very low C content (<1%), we conclude that intensive cultivation can lead to intensive soil degradation and expect future degradation of soils under young oil palms. This challenges the sustainability of agricultural intensification in Sumatra. Because Sumatra is a pioneer of tropical land-use change, this should be regarded as potential threats that other tropical regions may face in future."],["dc.identifier.doi","10.1016/j.agee.2016.07.002"],["dc.identifier.fs","622613"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/10574"],["dc.language.iso","en"],["dc.notes.status","final"],["dc.relation","SFB 990: Ökologische und sozioökonomische Funktionen tropischer Tieflandregenwald-Transformationssysteme (Sumatra, Indonesien)"],["dc.relation","SFB 990 | A | A04: Carbon stock, turnover and functions in heavily weathered soils under lowland rainforest transformation systems"],["dc.relation","SFB 990 | C | C01: Produktivität, Marktzugang und internationale Anbindung von kleinbäuerlicher Kautschuk- und Palmölerzeugung in der Provinz Jambi"],["dc.relation.issn","0167-8809"],["dc.subject.gro","sfb990_journalarticles"],["dc.title","Soil degradation in oil palm and rubber plantations under land resource scarcity"],["dc.type","journal_article"],["dc.type.internalPublication","unknown"],["dc.type.peerReviewed","unknown"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","104941"],["dc.bibliographiccitation.journal","Catena"],["dc.bibliographiccitation.volume","196"],["dc.contributor.author","Hennings, Nina"],["dc.contributor.author","Becker, Joscha N."],["dc.contributor.author","Guillaume, Thomas"],["dc.contributor.author","Damris, Muhammad"],["dc.contributor.author","Dippold, Michaela A."],["dc.contributor.author","Kuzyakov, Yakov"],["dc.date.accessioned","2021-04-14T08:30:34Z"],["dc.date.available","2021-04-14T08:30:34Z"],["dc.date.issued","2021"],["dc.identifier.doi","10.1016/j.catena.2020.104941"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/83287"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-399"],["dc.relation","SFB 990: Ökologische und sozioökonomische Funktionen tropischer Tieflandregenwald-Transformationssysteme (Sumatra, Indonesien)"],["dc.relation","SFB 990 | A | A04: Carbon stock, turnover and functions in heavily weathered soils under lowland rainforest transformation systems"],["dc.relation.issn","0341-8162"],["dc.relation.orgunit","Department für Nutzpflanzenwissenschaften"],["dc.subject.gro","sfb990_journalarticles"],["dc.title","Riparian wetland properties counter the effect of land-use change on soil carbon stocks after rainforest conversion to plantations"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]