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1. Moderate shading did not affect barley yield in temperate silvoarable agroforestry systems

Author:
Johan Six,   et al.   ; Christina Vaccaro; Christian Schöb;     Show all 3 Authors
Source:
Agroforestry systems 2022 v.96 no.4 pp. 799-810
ISSN:
0167-4366
Subject:
Hordeum vulgare; agroforestry; climate change; fearfulness; human population; irrigation; nutrient availability; seed weight; soil water; summer barley; tropics; understory; Switzerland
Abstract:
... With climate change and an increasing global human population, the concept of agroforestry is gaining economic and environmental interest. The practice of growing trees and crops on the same land is mainly applied in (sub)tropical climate and rarer in temperate areas where farmers fear decreased understorey crop yields due to competition with trees. However, whether competition is stronger below-  ...
DOI:
10.1007/s10457-022-00740-z

2. Effects of expanding cassava planting and harvesting windows on root yield, starch content and revenue in southwestern Nigeria

Author:
Johan Six,   et al.   ; Rebecca Oiza Enesi; Pieter Pypers; Christine Kreye; Meklit Tariku; Stefan Hauser;     Show all 6 Authors
Source:
Field crops research 2022 v.286 pp. 108639
ISSN:
0378-4290
Subject:
Manihot esculenta; cassava; commercialization; energy intake; perennials; prices; profitability; rain; research; seasonal variation; staple crops; starch; Nigeria
Abstract:
... Cassava (Manihot esculenta Crantz) is an important staple crop in Nigeria. It provides approximately 80 % of the caloric intake in Nigeria. High starch content and fresh root yields are important for the commercialization of cassava. Cassava is a perennial crop, and it can be produced all year round. However, cassava fresh root yield and starch content are strongly influenced by environmental cond ...
DOI:
10.1016/j.fcr.2022.108639

3. Raising up to the climate challenge - Understanding and assessing farmers’ strategies to build their resilience. A comparative analysis between Ugandan and Swiss farmers

Author:
Johan Six,   et al.   ; Ulysse Le Goff; Adelaide Sander; Maria Hernandez Lagana; Dominique Barjolle; Suzanne Phillips;     Show all 6 Authors
Source:
Journal of rural studies 2022 v.89 pp. 1-12
ISSN:
0743-0167
Subject:
agroecology; climate; climate change; farms; stakeholders; Switzerland; Uganda
Abstract:
... Climate change is a growing concern for farmers and food systems across the globe, raising interest in their resilience to climate change. Thus, exploring farm resilience in various contexts may help understand its prerequisites and build context and scale-specific strategies. Using an adaptive cycle framework through a survey-based assessment of the resilience of farmers in Uganda and Switzerland ...
DOI:
10.1016/j.jrurstud.2021.10.020

4. Greenhouse gas dynamics in an urbanized river system: influence of water quality and land use

Author:
Johan Six,   et al.   ; Long Ho; Ruben Jerves-Cobo; Matti Barthel; Samuel Bode; Pascal Boeckx; Peter Goethals;     Show all 7 Authors
Source:
Environmental science and pollution research 2022 v.29 no.25 pp. 37277-37290
ISSN:
0944-1344
Subject:
Oregon; ammonium; carbon dioxide; dissolved oxygen; greenhouses; land use; pollution; research; river water; rivers; runoff; sewage; statistical analysis; urbanization; water quality; Ecuador
Abstract:
... Rivers act as a natural source of greenhouse gases (GHGs). However, anthropogenic activities can largely alter the chemical composition and microbial communities of rivers, consequently affecting their GHG production. To investigate these impacts, we assessed the accumulation of CO₂, CH₄, and N₂O in an urban river system (Cuenca, Ecuador). High variation of dissolved GHG concentrations was found a ...
DOI:
10.1007/s11356-021-18081-2

5. Modelling soil water retention and water‐holding capacity with visible–near‐infrared spectra and machine learning

Author:
Johan Six,   et al.   ; Philipp Baumann; Juhwan Lee; Thorsten Behrens; Asim Biswas; Gordon McLachlan; Raphael A. Viscarra Rossel;     Show all 7 Authors
Source:
European journal of soil science 2022 v.73 no.2 pp. e13220
ISSN:
1351-0754
Subject:
air drying; artificial intelligence; available water capacity; field capacity; pedotransfer functions; soil water retention; spectroscopy; volumetric water content; water holding capacity
Abstract:
... We need measurements of soil water retention (SWR) and available water capacity (AWC) to assess and model soil functions, but methods are time‐consuming and expensive. Our aim here was to investigate the modelling of AWC and SWR with visible–near‐infrared spectra (vis–NIR) and the machine‐learning method cubist. We used soils from 54 locations across Australian agricultural regions, from three dep ...
DOI:
10.1111/ejss.13220

6. Cassava-maize intercropping systems in southern Nigeria: Radiation use efficiency, soil moisture dynamics, and yields of component crops

Author:
Johan Six,   et al.   ; Charles Chigemezu Nwokoro; Christine Kreye; Magdalena Necpalova; Olojede Adeyemi; Matti Barthel; Pieter Pypers; Stefan Hauser;     Show all 8 Authors
Source:
Field crops research 2022 v.283 pp. 108550
ISSN:
0378-4290
Subject:
biomass production; cassava; corn; fertilizer application; fertilizers; food security; grain yield; intercropping; photosynthetically active radiation; radiation use efficiency; rain; research; soil water; solar radiation; Nigeria
Abstract:
... Efficient utilization of incident solar radiation and rainwater conservation in rain-fed smallholder cropping systems require the development and adoption of cropping systems with high resource use efficiency. Due to the popularity of cassava-maize intercropping and the food security and economic importance of both crops in Nigeria, we investigated options to improve interception of photosynthetic ...
DOI:
10.1016/j.fcr.2022.108550

7. Assessment of sustainable land use: linking land management practices to sustainable land use indicators

Author:
Johan Six,   et al.   ; Generose Nziguheba; Julius Adewopo; Cargele Masso; Nsharwasi Leon Nabahungu; Haroon Sseguya; Godfrey Taulya; Bernard Vanlauwe;     Show all 8 Authors
Source:
International journal of agricultural sustainability 2022 v.20 no.3 pp. 265-288
ISSN:
1747-762X
Subject:
acidification; agricultural land; case studies; decision support systems; farms; food production; land degradation; nutrient balance; soil organic carbon; sustainable land management; Tanzania
Abstract:
... Land degradation threatens food production especially in smallholder farming systems predominant in sub-Saharan Africa. Monitoring the effects of agricultural land uses is critical to guide sustainable intensification (SI). There are various indicators of sustainable land use (SLU), but conventional methods to quantify their metrics are complex and difficult to deploy for rapid and large-scale ass ...
DOI:
10.1080/14735903.2021.1926150

8. Pedoclimatic factors and management determine soil organic carbon and aggregation in farmer fields at a regional scale

Author:
Johan Six,   et al.   ; Lucie Büchi; Florian Walder; Samiran Banerjee; Tino Colombi; Marcel G.A. van der Heijden; Thomas Keller; Raphaël Charles;     Show all 8 Authors
Source:
Geoderma 2022 v.409 pp. 115632
ISSN:
0016-7061
Subject:
agricultural land; biomarkers; clay; clay fraction; farmers; food security; microbial carbon; no-tillage; organic production; soil aggregates; soil conservation; soil organic carbon; soil quality; soil texture; winter wheat; Switzerland
Abstract:
... The degradation of soil from agricultural land is a major threat to food security and a driver of global changes. Soil conservation systems are thus being promoted and/or adopted worldwide. In this on-farm study conducted in Switzerland, we compared the effect of three cropping systems – conventional with tillage, conventional without tillage (i.e. no-till) and organic farming with tillage – on so ...
DOI:
10.1016/j.geoderma.2021.115632

9. Assessing between and within Product Group Variance of Environmental Efficiency of Swiss Agriculture Using Life Cycle Assessment and Data Envelopment Analysis

Author:
Johan Six,   et al.   ; Dario Pedolin; Thomas Nemecek;     Show all 3 Authors
Source:
Agronomy 2021 v.11 no.9 pp. -
ISSN:
2073-4395
Subject:
agronomy; cattle; cradle-to-gate; food production; milk; variance; Switzerland
Abstract:
... Food production systems can contribute to the degradation of the environment; thereby endangering the very resource, they depend on. However, while overall large, the environmental impacts of individual agricultural products are disparate. Therefore, in order to gain a better understanding of the impact different food production systems have on the environment, we should start at the produce level ...
DOI:
10.3390/agronomy11091862

10. A well‐established fact: Rapid mineralization of organic inputs is an important factor for soil carbon sequestration

Author:
Johan Six,   et al.   ; Denis Angers; Dominique Arrouays; Rémi Cardinael; Claire Chenu; Marc Corbeels; Julien Demenois; Mark Farrell; Manuel Martin; Budiman Minasny; Sylvie Recous;     Show all 11 Authors
Source:
European journal of soil science 2022 v.73 no.3 pp. e13242
ISSN:
1351-0754
Subject:
biodiversity; carbon sequestration; climate change; mineralization; soil; soil erosion; soil organic carbon
Abstract:
... We have read with interest an opinion paper recently published in the European Journal of Soil Science (Berthelin et al., 2022). This paper presents some interesting considerations, at least one of which is already well known to soil scientists working on soil organic carbon (SOC), that is, a large portion (80%–90%) of fresh carbon inputs to soil is subject to rapid mineralization. The short‐term ...
DOI:
10.1111/ejss.13242

11. Reduction of nitrogen pollution in agriculture through nitrogen surplus quotas: an analysis of individual marginal abatement cost and different quota allocation schemes using an agent-based model

Author:
Johan Six,   et al.   ; Alena Schmidt; Gabriele Mack; Stefan Mann;     Show all 4 Authors
Source:
Journal of environmental planning and management 2021 v.64 no.8 pp. 1375-1391
ISSN:
1360-0559
Subject:
agricultural industry; cost effectiveness; farms; marginal abatement cost; marginal abatement cost curve; models; nitrogen; pollution; poultry; swine
Abstract:
... Nitrogen (N) pollution has mostly been controlled using command-and-control instruments. However, nitrogen surplus permits (NSPs), which are tradeable, can be more cost-efficient in addressing the problem. To model this instrument, we calculated the individual marginal abatement cost curve for a sample of about 3,400 Swiss farms using farm-optimization models implemented in the agent-based agricul ...
DOI:
10.1080/09640568.2020.1823344

12. A comprehensive assessment of diversified cropping systems on agro-environmental sustainability in three Mediterranean long-term field experiments

Author:
Johan Six,   et al.   ; Silvia Vanino; Claudia Di Bene; Chiara Piccini; Gianni Fila; Bruno Pennelli; Raúl Zornoza; Virginia Sanchez-Navarro; Jorge Álvaro-Fuentes; Roman Hüppi; Roberta Farina;     Show all 11 Authors
Source:
European journal of agronomy 2022 v.140 pp. 126598
ISSN:
1161-0301
Subject:
agroecosystems; agronomy; bulk density; conservation tillage; crop diversification; crop rotation; disturbed soils; fuzzy logic; phosphorus; soil organic carbon; soil quality; sustainable land management; total nitrogen; Italy; Spain
Abstract:
... The intensification of agricultural systems has caused a noticeable impact on agro-ecosystem services. Thus, the adoption of more sustainable agricultural practices such as crop diversification and reduction of external inputs represent an alternative strategy to minimize the impacts of intensive agricultural systems to the environment. This study aimed at evaluating the effects of crop rotation, ...
DOI:
10.1016/j.eja.2022.126598

13. A food tax only minimally reduces the N surplus of Swiss agriculture

Author:
Johan Six,   et al.   ; Alena Schmidt; Magdalena Necpalova; Gabriele Mack; Anke Möhring;     Show all 5 Authors
Source:
Agricultural systems 2021 v.194 pp. 103271
ISSN:
0308-521X
Subject:
animals; farms; meat; milk; models; nitrogen; nutrient use efficiency
Abstract:
... Most Western-European countries exceed the critical loads for nitrogen (N) losses. High nitrogen (N) inputs make agriculture one of the largest contributors to N pollution. There might be a potential to reduce this losses with an output tax on animal products, as they have low N use efficiency and a tax has the potential to reduce the consumption of this products.We want to assess the potential of ...
DOI:
10.1016/j.agsy.2021.103271

14. Towards spatially continuous mapping of soil organic carbon in croplands using multitemporal Sentinel-2 remote sensing

Author:
Johan Six,   et al.   ; Pu Shi; Andrew Sila; Bernard Vanlauwe; Kristof Van Oost;     Show all 5 Authors
Source:
ISPRS journal of photogrammetry and remote sensing 2022 v.193 pp. 187-199
ISSN:
0924-2716
Subject:
Chernozems; agroecosystems; cropland; humans; landscapes; photogrammetry; prediction; soil degradation; soil organic carbon; space and time; China; Europe
Abstract:
... Intensified human activities can augment soil organic carbon (SOC) losses from the world’s croplands, making SOC a highly dynamic parameter both in space and time. Sentinel-2 spectral imagery is well placed to capture the spatiotemporal variability of SOC, but its capability has only been demonstrated for agricultural regions mostly located in Europe. Furthermore, most studies so far only used sin ...
DOI:
10.1016/j.isprsjprs.2022.09.013

15. Immobilization and stabilization of volcanic ash in soil aggregates in semiarid meadows of Northern Patagonia

Author:
Johan Six,   et al.   ; Andrea Soledad Enriquez; Magdalena Necpalova; María Victoria Cremona; Pablo Luís Peri;     Show all 5 Authors
Source:
Geoderma 2021 v.392 pp. 114987
ISSN:
0016-7061
Subject:
carbon dioxide; clay; ecosystems; land management; meadows; microaggregates; organic carbon; semiarid zones; silt; soil aggregation; soil organic matter; soil water content; total nitrogen; volcanic activity; volcanic ash; Argentina
Abstract:
... Although volcanism may be perceived by the society as a phenomenon with mostly negative consequences, this is not always the case especially for natural systems. There is a limited knowledge on how the deposited pristine ash becomes immobilized and stabilized in the soil after the volcanic event. Here, we studied processes of soil aggregates formation in the buried ash layer in an early stage of t ...
DOI:
10.1016/j.geoderma.2021.114987

16. Understanding changes in cassava root dry matter yield by different planting dates, crop ages at harvest, fertilizer application and varieties

Author:
Johan Six,   et al.   ; Rebecca Oiza Enesi; Stefan Hauser; Pieter Pypers; Christine Kreye; Meklit Tariku;     Show all 6 Authors
Source:
European journal of agronomy 2022 v.133 pp. 126448
ISSN:
1161-0301
Subject:
agronomy; cassava; drought; dry matter accumulation; experimental design; fertilizer application; fertilizers; income; perennials; prices; yields; Nigeria
Abstract:
... Cassava is a perennial crop that can adapt to periods of drought at different times in a growing season, which permits scheduling planting and harvest to develop production systems supplying roots continuously. However, farmers plant and harvest cassava at the onset of rains which creates glut and results in unattractive root prices. Thus, farmers need to understand how cassava varieties respond t ...
DOI:
10.1016/j.eja.2021.126448

17. Fluvial sediment export from pristine forested headwater catchments in the Congo Basin

Author:
Johan Six,   et al.   ; Simon Baumgartner; Marijn Bauters; Matti Barthel; Serge Alebadwa; Nadine Bahizire; Claudino Sumaili; Degra Ngoy; Merveille Kongolo; Basile Mujinya Bazirake; Landry Cizungu Ntaboba; Pascal Boeckx; Kristof Van Oost; Travis W. Drake;     Show all 14 Authors
Source:
Geomorphology 2022 v.398 pp. 108046
ISSN:
0169-555X
Subject:
Brachystegia; base flow; basins; carbon nitrogen ratio; forested watersheds; hysteresis; land use change; lowland forests; particulate organic matter; rain; rain intensity; sediment transport; sediments; storms; topsoil; tropical forests; understory; vegetation cover; water; wet season; woodlands; Central Africa
Abstract:
... Studies on sediment export from tropical forest watersheds are scarce. Of the assessments that do exist, most are of larger rivers or are model-based and lack validation with measured data. Understanding the mechanisms of sediment export dynamics in forested headwaters is important for assessing downstream effects and as a baseline for net impacts of land-use change. To that end, we quantified ann ...
DOI:
10.1016/j.geomorph.2021.108046

18. Beyond feasibility—the role of motivation to implement measures to enhance resilience : Evidence from drought-affected smallholder farmers in Ghana and Ethiopia

Author:
Johan Six,   et al.   ; Luzian Messmer; Braida Thom; Pius Kruetli; Evans Dawoe; Kebebew Assefa; Jonas Joerin;     Show all 7 Authors
Source:
Mitigation and adaptation strategies for global change 2021 v.26 no.5 pp. 19
ISSN:
1381-2386
Subject:
Eragrostis tef; bookkeeping; drought; food security; global change; irrigation; motivation; probability; questionnaires; viability; weather forecasting; Ethiopia; Ghana
Abstract:
... Many regions around the world are experiencing an increase in climate-related shocks, such as drought. This poses serious threats to farming activities and has major implications for sustaining rural livelihoods and food security. Farmers’ ability to respond to and withstand the increasing incidence of drought events needs to be strengthened and their resilience enhanced. Implementation of measure ...
DOI:
10.1007/s11027-021-09952-7

19. Mechanisms influencing physically sequestered soil carbon in temperate restored grasslands in South Africa and North America

Author:
Johan Six,   et al.   ; Drew A. Scott; Elizabeth M. Bach; Chris C. Du Preez; Sara G. Baer;     Show all 5 Authors
Source:
Biogeochemistry 2021 v.156 no.1 pp. 131-143
ISSN:
0168-2563
Subject:
bulk density; carbon; carbon dioxide; carbon nitrogen ratio; clay; clay fraction; data collection; equations; grassland soils; microbial biomass; models; phospholipid fatty acids; soil aggregation; soil carbon; soil structure; structural equation modeling; vesicular arbuscular mycorrhizae; Kansas; Nebraska; South Africa
Abstract:
... Sequestering carbon (C) into stable soil pools has potential to mitigate increasing atmospheric carbon dioxide concentrations. Carbon accrues in grassland soil restored from cultivation, but the amount of physically protected C (here measured as microaggregate-within-macroaggregate C) and predominant mechanisms of accrual are not well understood. We modeled the rate of physically protected carbon ...
DOI:
10.1007/s10533-021-00774-y

20. Trees enhance abundance of arbuscular mycorrhizal fungi, soil structure, and nutrient retention in low-input maize cropping systems

Author:
Johan Six,   et al.   ; Janina Dierks; Wilma J. Blaser-Hart; Hannes A. Gamper; Isaac Betserai Nyoka; Edmundo Barrios;     Show all 6 Authors
Source:
Agriculture, ecosystems & environment 2021 v.318 pp. 107487
ISSN:
0167-8809
Subject:
Faidherbia albida; Mangifera indica; agriculture; agroecosystems; agroforestry; biomass; carbon; corn; environment; hyphae; mangoes; mycelium; nitrogen; nutrient retention; phosphorus; soil aggregation; soil degradation; soil fertility; soil structure; sustainable agriculture; vesicular arbuscular mycorrhizae
Abstract:
... Retaining trees in low-input agroecosystems could be key to maintain mycelia of arbuscular mycorrhizal fungi (AMF) and hence, improve soil fertility and crop performance. We assessed the impact of faidherbia (Faidherbia albida, Fabaceae) and mango (Mangifera indica, Anacardiaceae) trees on AMF and soil fertility in smallholder farmers’ maize fields. Along distance-from-tree gradients (1, 4, 10, 15 ...
DOI:
10.1016/j.agee.2021.107487