An ecological transition during juvenile life in a marine snail

Chitin oligosaccharides (COs) hold high promise as organic fertilizers in the ongoing agro-ecological transition. Short- and long-chain COs can contribute to the establishment of symbiotic associations between plants and microorganisms, facilitating the uptake of soil nutrients by host plants. Long-chain COs trigger plant innate immunity. A fine investigation of these different signaling pathways requires improving the access to high-purity COs. Here, we used the response surface methodology to optimize the production of COs by enzymatic hydrolysis of water-soluble chitin (WSC) with hen egg-white lysozyme. The influence of WSC concentration, its acetylation degree, and the reaction time course were modelled using a Box–Behnken design. Under optimized conditions, water-soluble COs up to the nonasaccharide were formed in 51% yield and purified to homogeneity. This straightforward approach opens new avenues to determine the complex roles of COs in plants.

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Earthworm Inoculation Improves Upland Rice Crop Yield and Other Agrosystem Services in Madagascar

Agriculture ◽

10.3390/agriculture11010060 ◽

2021 ◽

Vol 11 (1) ◽

pp. 60

Author(s):

Onja Ratsiatosika ◽

Malalatiana Razafindrakoto ◽

Tantely Razafimbelo ◽

Michel Rabenarivo ◽

Thierry Becquer ◽

...

Keyword(s):

Upland Rice ◽

Cropping Systems ◽

Conservation Agriculture ◽

Biological Properties ◽

Rice Grain ◽

Positive Effects ◽

Ecological Transition ◽

Earthworm Activity ◽

Endogeic Earthworms ◽

Plant Properties

The effects of earthworm inoculation and cropping systems on upland rice systems were examined over a four-year period in the Highlands of Madagascar. Each year, endogeic earthworms Pontoscolex corethrurus (Rhinodrilidae) were inoculated (EW+) at a density of 75 ind m−2 or were not inoculated (EW0). Inoculation was tested in three cropping systems: conservation agriculture (CA) and traditional tillage with or without residues restitution. Soil and plant properties were measured during the first three years while soil biological properties were assessed at the fourth year. At the end of the experiment, earthworm density was three-fold higher in EW+ than in EW0, demonstrating the success of the inoculation. Earthworm density was more important in CA than in tillage systems. Earthworm inoculation had higher significant effects on soil and plant properties than cropping systems. Earthworm inoculation had positive effects on soil macroaggregation (+43%), aboveground biomass (+27%), rice grain yield (+45%), and N grain amount (+43%). Intensifying earthworm activity in field conditions to meet the challenge of ecological transition is supported by our study.

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Sustainable Mobility and the Institutional Lock-In: The Example of Rural France

Sustainability ◽

10.3390/su13042189 ◽

2021 ◽

Vol 13 (4) ◽

pp. 2189

Author(s):

Aurore Flipo ◽

Madeleine Sallustio ◽

Nathalie Ortar ◽

Nicolas Senil

Keyword(s):

Rural Areas ◽

Sustainable Mobility ◽

Local Mobility ◽

European Public ◽

Determining Factors ◽

Anthropological Fieldwork ◽

Lock In ◽

Rural France ◽

Ecological Transition

Sustainable mobility issues in rural areas, compared with urban mobility issues, have so far been poorly covered in the French and European public debate. However, local mobility issues are determining factors in territorial inequalities, regional development and ecological transition. This paper is based on preliminary findings of qualitative socio-anthropological fieldwork carried out in two rural departments of the Auvergne-Rhône-Alpes region: Drôme and Ardèche. Our objective is to highlight how the question of sustainable local mobility is linked to governance issues and multiple overlapping institutions. We argue that analyzing stakeholders’ strategies and territorial governance is key to understanding the contemporary dynamics surrounding a transition towards a more sustainable mobility in rural areas. In order to do so, we show how the debates surrounding the adoption of a law allowing for the transfer of responsibility to local authorities for the organization of mobility services reveals the complexity of local mobility governance in rural areas and provides material for the analysis of the logics of stakeholder engagement, cooperation and conflict within the field of sustainable mobility. Through the case study of the organization of a local public transport service in a rural area, we shed light on the action of multiple stakeholders and their potentially antagonistic objectives.

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