van Straaten, Oliver

[["dc.bibliographiccitation.firstpage","55"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Plant Ecology"],["dc.bibliographiccitation.lastpage","66"],["dc.bibliographiccitation.volume","216"],["dc.contributor.author","Thonhofer, Joachim"],["dc.contributor.author","Getto, Daniela"],["dc.contributor.author","van Straaten, Oliver"],["dc.contributor.author","Cicuzza, Daniele"],["dc.contributor.author","Kessler, Michael"],["dc.date.accessioned","2018-11-07T10:03:54Z"],["dc.date.available","2018-11-07T10:03:54Z"],["dc.date.issued","2015"],["dc.description.abstract","Rattan palms are dominant elements of Southeast Asian rainforests and of high economic importance, yet little is known about the ecological factors determining the spatial distribution of species and assemblages. We studied rattan palm assemblages at two sites at different elevations in Lore Lindu National Park, Sulawesi, Indonesia (Pono: 958-1,266 m; Bariri: 1,390-1,507 m). At each site, we established a transect of 1.29 km consisting of 65 study plots of 10 x 10 m(2) each, regularly spaced 20 m from each other. In total, we recorded 5,081 rattan individuals belonging to 22 species, with 1,367 individuals of 16 species at Pono and 3,714 individuals of 8 species at Bariri. Variance partitioning explained 29-49 % of community variation at Pono and 40-72 % at Bariri, with most variation jointly explained by spatial and environmental variables. Within the environmental influence, soil factors dominated over local topographical ones. RDA ordination allowed the discrimination of four species groups at Pono and three groups at Bariri. These groups were related to soil and less clearly to topographic variables. Our study is the first documentation of the importance of soil parameters in determining the spatial distribution of rattan palms. Interestingly, juvenile palms (< 1 m tall) showed closer relationships to environmental factors than adult plants (> 1 m tall), calling for further studies on the demography of rattan palms."],["dc.description.sponsorship","German Research Foundation (DFG) [SFB 552]"],["dc.identifier.doi","10.1007/s11258-014-0416-x"],["dc.identifier.isi","000347696700005"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/38577"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","1573-5052"],["dc.relation.issn","1385-0237"],["dc.title","Influence of spatial and environmental variables on rattan palm (Arecaceae) assemblage composition in Central Sulawesi, Indonesia"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.issue","9"],["dc.bibliographiccitation.journal","Global Biogeochemical Cycles"],["dc.bibliographiccitation.volume","34"],["dc.contributor.author","Finstad, Kari"],["dc.contributor.author","Straaten, Oliver"],["dc.contributor.author","Veldkamp, Edzo"],["dc.contributor.author","McFarlane, Karis"],["dc.date.accessioned","2021-04-14T08:23:14Z"],["dc.date.available","2021-04-14T08:23:14Z"],["dc.date.issued","2020"],["dc.description.abstract","Tropical forests account for a large portion of the Earth's terrestrial carbon pool. However, rapid deforestation threatens the stability of this carbon. We examine radiocarbon (Δ14C) and stable carbon (δ13C) isotopes of soil organic matter to provide insight into rates of carbon turnover, inputs, and losses of pasture-derived (C4) versus forest or oil palm-derived (C3) carbon. Data are presented for natural lowland forests on mineral soil converted to pastures in Peru and to oil palm plantations in Peru, Indonesia, and Cameroon. We additionally examine plots of secondary forests following agricultural use. There were large losses in carbon stocks under both pasture and oil palms. In the plots converted to pasture, our data indicate a preferential loss of relatively young carbon, and a greater loss of forest-derived carbon than replacement with pasture-derived carbon. Natural forests converted directly to oil palm plantations sustained losses in carbon, but Δ14C values suggest that the soil may retain a sufficient amount of newly acquired carbon to offset initial losses of young carbon. Furthermore, replacement of pastures with oil palm plantations facilitates the accumulation of young carbon, which may lead to a gradual increase in carbon stocks. The sites examined here are representative of the biophysical characteristics in roughly half of the humid tropics, suggesting that these findings may be applicable to a large area of similarly managed mineral soils in lowland tropical forests."],["dc.identifier.doi","10.1029/2019GB006461"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/80837"],["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 | A05: Optimierung des Nährstoffmanagements in Ölpalmplantagen und Hochrechnung plot-basierter Treibhausgasflüsse auf die Landschaftsebene transformierter Regenwälder"],["dc.relation.eissn","1944-9224"],["dc.relation.issn","0886-6236"],["dc.rights","CC BY-NC-ND 4.0"],["dc.subject.gro","sfb990_journalarticles"],["dc.title","Soil Carbon Dynamics Following Land Use Changes and Conversion to Oil Palm Plantations in Tropical Lowlands Inferred From Radiocarbon"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","117522"],["dc.bibliographiccitation.journal","Forest Ecology and Management"],["dc.bibliographiccitation.volume","451"],["dc.contributor.author","Tchiofo Lontsi, Rodine"],["dc.contributor.author","Corre, Marife D."],["dc.contributor.author","van Straaten, Oliver"],["dc.contributor.author","Veldkamp, Edzo"],["dc.date.accessioned","2019-12-13T16:52:30Z"],["dc.date.available","2019-12-13T16:52:30Z"],["dc.date.issued","2019"],["dc.description.abstract","Although disturbances associated with selective logging can cause pronounced changes in soil characteristics and nutrient stocks, such information is very limited for highly weathered soils in Africa. We assessed the effects of reduced impact logging (RIL, with a 30-year rotation management plan) and conventional logging (CL, without a management plan) on physical and biochemical characteristics of Ferralsol soils that developed on pre-Cambrian rocks in rainforests of Cameroon. Five to seven months after the logging operations were completed, we mapped the CL and RIL sites and quantified the disturbed areas: felling gaps, skidding trails, logging decks and roads. We selected four replicate plots at each site that encompassed these four disturbed strata and an adjacent undisturbed area as the reference. At each disturbed stratum and reference area per plot, we took soil samples down to 50 cm, and quantified soil physical and biochemical characteristics. Nutrient exports with timber harvest were also quantified. The logging intensity was very low with removals of 0.2 and 0.3 tree per hectare, and the ground area disturbed accounted only 5.2% and 4.0% of the total area in CL and RIL, respectively. In terms of area disturbance for each harvested tree, CL had 753 m 2 tree −1 more affected ground area than RIL. Roads and logging decks were the most affected by logging operations, where effective cation exchange capacity, soil organic carbon (SOC), total nitrogen (N), Bray-extractable phosphorus (P) and exchangeable aluminum decreased whereas pH, 15 N natural abundance and exchangeable manganese increased compared to the undisturbed reference area (P < 0.01-0.04). The disturbed area showed overall reductions of 21-29% in SOC, N and P stocks relative to the reference areas (P = 0.02-0.07). The amounts of C, N, P and base cations exported with harvested timber were only 0.4-5.9% of the changes in stocks of these elements in the disturbed strata. Nutrient reductions in the soil and exports through timber harvest were comparable between CL and RIL, after one logging event in this very low intensity logging systems. Our results suggest that unplanned operations together with frequent re-logging inherent to CL can increase area damage and enhance changes in SOC and nutrients as opposed to RIL, which may affect the recovery of the succeeding vegetation."],["dc.identifier.doi","10.1016/j.foreco.2019.117522"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/62756"],["dc.language.iso","en"],["dc.relation.issn","0378-1127"],["dc.title","Changes in soil organic carbon and nutrient stocks in conventional selective logging versus reduced-impact logging in rainforests on highly weathered soils in Southern Cameroon"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","Ecology"],["dc.bibliographiccitation.volume","103"],["dc.contributor.affiliation","Corre, Marife D.; 1\r\nDepartment of Soil Science of Tropical and Subtropical Ecosystems\r\nGeorg‐August University of Goettingen\r\nGoettingen Germany"],["dc.contributor.affiliation","Aleeje, Alfred; 2\r\nDepartment of Agricultural Production\r\nMakerere University\r\nKampala Uganda"],["dc.contributor.affiliation","Mwanjalolo, Majaliwa J. G.; 3\r\nDepartment of Geography, Geo‐Informatics and Climate Sciences\r\nMakerere University\r\nKampala Uganda"],["dc.contributor.affiliation","Babweteera, Fred; 5\r\nDepartment of Forestry, Biodiversity and Tourism\r\nMakerere University\r\nKampala Uganda"],["dc.contributor.affiliation","Veldkamp, Edzo; 1\r\nDepartment of Soil Science of Tropical and Subtropical Ecosystems\r\nGeorg‐August University of Goettingen\r\nGoettingen Germany"],["dc.contributor.affiliation","van Straaten, Oliver; 1\r\nDepartment of Soil Science of Tropical and Subtropical Ecosystems\r\nGeorg‐August University of Goettingen\r\nGoettingen Germany"],["dc.contributor.author","Manu, Raphael"],["dc.contributor.author","Corre, Marife D."],["dc.contributor.author","Aleeje, Alfred"],["dc.contributor.author","Mwanjalolo, Majaliwa J. G."],["dc.contributor.author","Babweteera, Fred"],["dc.contributor.author","Veldkamp, Edzo"],["dc.contributor.author","Straaten, Oliver"],["dc.date.accessioned","2022-04-01T10:02:12Z"],["dc.date.available","2022-04-01T10:02:12Z"],["dc.date.issued","2022"],["dc.date.updated","2022-06-14T23:31:13Z"],["dc.description.abstract","Abstract Experimental evidence of nutrient limitations on primary productivity in Afrotropical forests is rare and globally underrepresented yet are crucial for understanding constraints to terrestrial carbon uptake. In an ecosystem‐scale nutrient manipulation experiment, we assessed the early responses of tree growth rates among different tree sizes, taxonomic species, and at a community level in a humid tropical forest in Uganda. Following a full factorial design, we established 32 (eight treatments × four replicates) experimental plots of 40 × 40 m each. We added nitrogen (N), phosphorus (P), potassium (K), their combinations (NP, NK, PK, and NPK), and control at the rates of 125 kg N ha−1 year−1, 50 kg P ha−1 year−1 and 50 kg K ha−1 year−1, split into four equal applications, and measured stem growth of more than 15,000 trees with diameter at breast height (dbh) ≥1 cm. After 2 years, the response of tree stem growth to nutrient additions was dependent on tree sizes, species and leaf habit but not community wide. First, tree stem growth increased under N additions, primarily among medium‐sized trees (10–30 cm dbh), and in trees of Lasiodiscus mildbraedii in the second year of the experiment. Second, K limitation was evident in semi‐deciduous trees, which increased stem growth by 46% in +K than –K treatments, following a strong, prolonged dry season during the first year of the experiment. This highlights the key role of K in stomatal regulation and maintenance of water balance in trees, particularly under water‐stressed conditions. Third, the role of P in promoting tree growth and carbon accumulation rates in this forest on highly weathered soils was rather not pronounced; nonetheless, mortality among saplings (1–5 cm dbh) was reduced by 30% in +P than in –P treatments. Although stem growth responses to nutrient interaction effects were positive or negative (likely depending on nutrient combinations and climate variability), our results underscore the fact that, in a highly diverse forest ecosystem, multiple nutrients and not one single nutrient regulate tree growth and aboveground carbon uptake due to varying nutrient requirements and acquisition strategies of different tree sizes, species, and leaf habits."],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659"],["dc.identifier.doi","10.1002/ecy.3659"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/105848"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-530"],["dc.publisher","John Wiley & Sons, Inc."],["dc.relation.eissn","1939-9170"],["dc.relation.issn","0012-9658"],["dc.rights","This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes."],["dc.rights.uri","http://onlinelibrary.wiley.com/termsAndConditions#vor"],["dc.title","Responses of tree growth and biomass production to nutrient addition in a semi‐deciduous tropical forest in Africa"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","5131"],["dc.bibliographiccitation.issue","16"],["dc.bibliographiccitation.journal","Biogeosciences"],["dc.bibliographiccitation.lastpage","5154"],["dc.bibliographiccitation.volume","15"],["dc.contributor.author","Kurniawan, Syahrul"],["dc.contributor.author","Corre, Marife D."],["dc.contributor.author","Matson, Amanda L."],["dc.contributor.author","Schulte-Bisping, Hubert"],["dc.contributor.author","Utami, Sri Rahayu"],["dc.contributor.author","van Straaten, Oliver"],["dc.contributor.author","Veldkamp, Edzo"],["dc.date.accessioned","2019-07-09T11:45:54Z"],["dc.date.available","2019-07-09T11:45:54Z"],["dc.date.issued","2018"],["dc.description.abstract","Conversion of forest to rubber and oil palm plantations is widespread in Sumatra, Indonesia, and it is largely unknown how such land-use conversion affects nutrient leaching losses. Our study aimed to quantify nutrient leaching and nutrient retention efficiency in the soil after land-use conversion to smallholder rubber and oil palm plantations. In Jambi province, Indonesia, we selected two landscapes on highly weathered Acrisol soils that mainly differed in texture: loam and clay. Within each soil type, we compared two reference land uses, lowland forest and jungle rubber (defined as rubber trees interspersed in secondary forest), with two converted land uses: smallholder rubber and oil palm plantations. Within each soil type, the first three land uses were represented by 4 replicate sites and the oil palm by three sites, totaling 30 sites. We measured leaching losses using suction cup lysimeters sampled biweekly to monthly from February to December 2013. Forests and jungle rubber had low solute concentrations in drainage water, suggesting low internal inputs of rock-derived nutrients and efficient internal cycling of nutrients. These reference land uses on the clay Acrisol soils had lower leaching of dissolved N and base cations (P D0.01–0.06) and higher N and base cation retention efficiency (P < 0.01–0.07) than those on the loam Acrisols. In the converted land uses, particularly on the loam Acrisol, the fertilized area of oil palm plantations showed higher leaching of dissolved N, organic C, and base cations (P < 0.01–0.08) and lower N and base cation retention efficiency compared to all the other land uses (P < 0.01–0.06). The unfertilized rubber plantations, particularly on the loam Acrisol, showed lower leaching of dissolved P (P D 0:08) and organic C (P < 0.01) compared to forest or jungle rubber, reflecting decreases in soil P stocks and C inputs to the soil. Our results suggest that land-use conversion to rubber and oil palm causes disruption of initially efficient nutrient cycling, which decreases nutrient availability. Over time, smallholders will likely be increasingly reliant on fertilization, with the risk of diminishing water quality due to increased nutrient leaching. Thus, there is a need to develop management practices to minimize leaching while sustaining productivity."],["dc.identifier.doi","10.5194/bg-15-5131-2018"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/15340"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/59333"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation","SFB 990: Ökologische und sozioökonomische Funktionen tropischer Tieflandregenwald-Transformationssysteme (Sumatra, Indonesien)"],["dc.relation","SFB 990 | A | A05: Optimierung des Nährstoffmanagements in Ölpalmplantagen und Hochrechnung plot-basierter Treibhausgasflüsse auf die Landschaftsebene transformierter Regenwälder"],["dc.relation.issn","1726-4189"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.subject.ddc","570"],["dc.subject.gro","sfb990_journalarticles"],["dc.title","Conversion of tropical forests to smallholder rubber and oil palm plantations impacts nutrient leaching losses and nutrient retention efficiency in highly weathered soils"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","132"],["dc.bibliographiccitation.journal","Journal of Arid Environments"],["dc.bibliographiccitation.lastpage","140"],["dc.bibliographiccitation.volume","165"],["dc.contributor.author","van Straaten, Oliver"],["dc.contributor.author","Doamba, Sabine W.M.F."],["dc.contributor.author","Corre, Marife D."],["dc.contributor.author","Veldkamp, Edzo"],["dc.date.accessioned","2020-12-10T14:24:50Z"],["dc.date.available","2020-12-10T14:24:50Z"],["dc.date.issued","2019"],["dc.identifier.doi","10.1016/j.jaridenv.2019.02.013"],["dc.identifier.issn","0140-1963"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/72361"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.title","Impacts of burning on soil trace gas fluxes in two wooded savanna sites in Burkina Faso"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","art119"],["dc.bibliographiccitation.issue","10"],["dc.bibliographiccitation.journal","Ecosphere"],["dc.bibliographiccitation.lastpage","22"],["dc.bibliographiccitation.volume","2"],["dc.contributor.author","van Straaten, Oliver"],["dc.contributor.author","Veldkamp, Edzo"],["dc.contributor.author","Corre, Marife D."],["dc.date.accessioned","2021-12-08T12:28:06Z"],["dc.date.available","2021-12-08T12:28:06Z"],["dc.date.issued","2011"],["dc.description.abstract","Climate models predict that the frequency and intensity of ENSO-related droughts will increase in Southeast Asia, yet little is known about how changes in precipitation patterns will affect soil CO2 efflux. Our objective was to determine drought responses on soil CO2 efflux, CO2 production sources (leaf litter, belowground heterotrophic (microbial) and autotrophic (root) respiration), and on CO2 production within the top 250 cm of soil. We simulated drought conditions in a sub-montane forest in Indonesia by constructing large throughfall displacement roofs in three 40 × 40 m plots and compared measurements with three control plots. The study lasted for 31 months with biweekly measurements: 2.5 months pre-treatment, 9 months of 50% roof closure followed by 15.5 months of 80% closure (46 ± 13% and 80 ± 12% throughfall reductions, respectively), and 4 months of roof opening. Soil CO2 efflux from the control plots was 11.7 ± 1.1 Mg C·ha−1·yr−1 and the contributions from leaf litter respiration, belowground heterotrophic respiration and autotrophic respiration were 29 ± 4%, 45 ± 6% and 30 ± 3%, respectively. Carbon dioxide production in the top 50 cm contributed 65% of the total production within 250 cm. During the simulated drought, soil CO2 efflux declined by 23% in the first 9 months and 48% in the next 15.5 months compared to the control. This was accompanied by significant decreases in both autotrophic and heterotrophic sources. Following roof opening, soil CO2 efflux rebounded slowly, but did not surpass the control. Soil matric potential exhibited an exponential relationship with soil CO2 efflux. The strong drought-induced decrease in soil respiration indicates that this forest ecosystem is drought sensitive, but could recover with commencement of normal rainfall levels."],["dc.identifier.doi","10.1890/ES11-00079.1"],["dc.identifier.gro","3150185"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/95555"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-476"],["dc.notes.status","final"],["dc.relation.issn","2150-8925"],["dc.rights.uri","http://doi.wiley.com/10.1002/tdm_license_1.1"],["dc.subject","Keywords: experimental drought;litter removal;root exclusion;soil CO2 efflux; soil CO2 production; throughfall displacement roof; tropical sub-montane forest"],["dc.title","Simulated drought reduces soil CO 2 efflux and production in a tropical forest in Sulawesi, Indonesia"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","no"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","5377"],["dc.bibliographiccitation.issue","21"],["dc.bibliographiccitation.journal","Biogeosciences"],["dc.bibliographiccitation.lastpage","5397"],["dc.bibliographiccitation.volume","17"],["dc.contributor.author","Iddris, Najeeb Al-Amin"],["dc.contributor.author","Corre, Marife D."],["dc.contributor.author","Yemefack, Martin"],["dc.contributor.author","van Straaten, Oliver"],["dc.contributor.author","Veldkamp, Edzo"],["dc.date.accessioned","2021-04-14T08:31:02Z"],["dc.date.available","2021-04-14T08:31:02Z"],["dc.date.issued","2020"],["dc.identifier.doi","10.5194/bg-17-5377-2020"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/17666"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/83462"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-399"],["dc.notes.intern","Merged from goescholar"],["dc.relation.eissn","1726-4189"],["dc.rights","CC BY 4.0"],["dc.rights.uri","http://creativecommons.org/licenses/by/4.0/"],["dc.title","Stem and soil nitrous oxide fluxes from rainforest and cacao agroforest on highly weathered soils in the Congo Basin"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","13"],["dc.bibliographiccitation.journal","SOIL"],["dc.bibliographiccitation.lastpage","23"],["dc.bibliographiccitation.volume","2"],["dc.contributor.author","Hombegowda, H. C."],["dc.contributor.author","van Straaten, Oliver"],["dc.contributor.author","Köhler, M."],["dc.contributor.author","Hölscher, Dirk"],["dc.date.accessioned","2017-09-07T11:45:36Z"],["dc.date.available","2017-09-07T11:45:36Z"],["dc.date.issued","2016"],["dc.description.abstract","Tropical agroforestry has an enormous potential to sequester carbon while simultaneously producing agricultural yields and tree products. The amount of soil organic carbon (SOC) sequestered is influenced by the type of the agroforestry system established, the soil and climatic conditions, and management. In this regional-scale study, we utilized a chronosequence approach to investigate how SOC stocks changed when the original forests are converted to agriculture, and then subsequently to four different agroforestry systems (AFSs): home garden, coffee, coconut and mango. In total we established 224 plots in 56 plot clusters across 4 climate zones in southern India. Each plot cluster consisted of four plots: a natural forest reference, an agriculture reference and two of the same AFS types of two ages (30–60 years and > 60 years). The conversion of forest to agriculture resulted in a large loss the original SOC stock (50–61 %) in the top meter of soil depending on the climate zone. The establishment of home garden and coffee AFSs on agriculture land caused SOC stocks to rebound to near forest levels, while in mango and coconut AFSs the SOC stock increased only slightly above the agriculture SOC stock. The most important variable regulating SOC stocks and its changes was tree basal area, possibly indicative of organic matter inputs. Furthermore, climatic variables such as temperature and precipitation, and soil variables such as clay fraction and soil pH were likewise all important regulators of SOC and SOC stock changes. Lastly, we found a strong correlation between tree species diversity in home garden and coffee AFSs and SOC stocks, highlighting possibilities to increase carbon stocks by proper tree species assemblies."],["dc.identifier.doi","10.5194/soil-2-13-2016"],["dc.identifier.fs","625149"],["dc.identifier.gro","3149043"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/5686"],["dc.language.iso","en"],["dc.notes.intern","Hoelscher Crossref import"],["dc.notes.status","final"],["dc.notes.submitter","chake"],["dc.relation.issn","2199-398X"],["dc.title","On the rebound: soil organic carbon stocks can bounce back to near forest levels when agroforests replace agriculture in southern India"],["dc.type","journal_article"],["dc.type.internalPublication","unknown"],["dc.type.peerReviewed","no"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1223"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","Biogeosciences"],["dc.bibliographiccitation.lastpage","1235"],["dc.bibliographiccitation.volume","7"],["dc.contributor.author","van Straaten, Oliver"],["dc.contributor.author","Veldkamp, Edzo"],["dc.contributor.author","Köhler, M."],["dc.contributor.author","Anas, Iswandi"],["dc.date.accessioned","2017-09-07T11:43:36Z"],["dc.date.available","2017-09-07T11:43:36Z"],["dc.date.issued","2010"],["dc.description.abstract","Climate change induced droughts pose a serious threat to ecosystems across the tropics and sub-tropics, particularly to those areas not adapted to natural dry periods. In order to study the vulnerability of cacao (Theobroma cacao) – Gliricidia sepium agroforestry plantations to droughts a large scale throughfall displacement roof was built in Central Sulawesi, Indonesia. In this 19-month experiment, we compared soil surface CO2 efflux (soil respiration) from three roof plots with three adjacent control plots. Soil respiration rates peaked at intermediate soil moisture conditions and decreased under increasingly dry conditions (drought induced), or increasingly wet conditions (as evidenced in control plots). The roof plots exhibited a slight decrease in soil respiration compared to the control plots (average 13% decrease). The strength of the drought effect was spatially variable – while some measurement chamber sites reacted strongly (responsive) to the decrease in soil water content (up to R2=0.70) (n=11), others did not react at all (non-responsive) (n=7). A significant correlation was measured between responsive soil respiration chamber sites and sap flux density ratios of cacao (R=0.61) and Gliricidia (R=0.65). Leaf litter CO2 respiration decreased as conditions became drier. The litter layer contributed approximately 3–4% of the total CO2 efflux during dry periods and up to 40% during wet periods. Within days of roof opening soil CO2 efflux rose to control plot levels. Thereafter, CO2 efflux remained comparable between roof and control plots. The cumulative effect on soil CO2 emissions over the duration of the experiment was not significantly different: the control plots respired 11.1±0.5 Mg C ha−1 yr−1, while roof plots respired 10.5±0.5 Mg C ha−1 yr−1. The relatively mild decrease measured in soil CO2 efflux indicates that this agroforestry ecosystem is capable of mitigating droughts with only minor stress symptoms."],["dc.identifier.doi","10.5194/bg-7-1223-2010"],["dc.identifier.fs","574214"],["dc.identifier.gro","3150173"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/5733"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/6908"],["dc.language.iso","en"],["dc.notes.intern","Migrated from goescholar"],["dc.notes.status","final"],["dc.relation.issn","1726-4189"],["dc.rights","Goescholar"],["dc.rights.access","openAccess"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.subject","CO2"],["dc.subject.ddc","570"],["dc.title","Spatial and temporal effects of drought on soil CO2 efflux in a cacao agroforestry system in Sulawesi, Indonesia"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","no"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]