Innovative Approaches to Analysing Carbon Sequestration as a Mitigation Strategy in Tropical Pasture Landscapes in Two Emblematic Contexts, the Amazon and the West African Sahel

The relationship between ruminant production systems and climate change is complex. As a major contributor to greenhouse gas (GHG) emissions, the sector has been the subject of considerable controversy, with particularly severe criticism in the 2000s. However, ten years ago, the attitude towards grazing lands began to change. Their efficient use of non-renewable energy and their contribution to carbon (C) sequestration were considered as key factors in the new environmental challenge. The reality of this mitigation potential was recently called into question once again in the global agriculture and climate change debate, including that of sequestration in the soil where grazing lands occupy a major position (30-40% of the land surface representing 30% of the soil organic C of the world). Few scientific references are available on these questions in tropical regions, and the standard metrics and methods used may turn out to be unsuitable for the correct evaluation of grazed ecosystems in these regions. Significant work is therefore required to establish baselines and design strategies to ensure sustainable grazing in these regions where the global sequestration potential is high relative to the surface areas concerned. To contribute to this debate, we focus on mitigation options offered by rangelands and grasslands and their management in two emblematic tropical contexts, humid and dry tropics, where field studies have been based on original and holistic approaches at different levels. In Amazonia, if curbing deforestation remains a priority, it needs to be accompanied by sustainable management of deforested areas. In the French Amazon (French Guiana), monitoring fields using chronosequences and flux towers has produced scientific knowledge on the significant mitigation capacities of grassland ecosystems. In the Brazilian Amazon, the spatial logic of the agro-ecological intensification of forage production has enabled a transition from individual extractive systems to farm management at communal levels. In the West African Sahelian region (Northern Senegal), an integrative study at landscape scale revealed the unexpected capacity of soil and shrubs for C sequestration that can offset the GHG emissions for which pastoralism in dry tropical zones is usually blamed

Restoring Value to Grassland Initiative: To Maintain the Environmental and Economic Value of Grasslands and to Promote Their Social and Cultural Functions

The Global Agenda for Sustainable Livestock (GASL), a multi-stakeholder partnership started in 2013 includes nine action networks (ANs). The networks are the working engine of GASL and are tasked with implementing activities, reports, providing evidence, guidelines and information on good practices demonstrated by the livestock sector. This paper outlines the activities of the network AN2 “Restoring Value to Grassland”, the purpose of which is to “maintain, restore and enhance environmental and economic value of grasslands, while promoting their social and cultural functions globally”. Since 2014, AN2 workshops have been held annually with scientists and stakeholders from rangeland/grassland biomes in Latin America (Brazil, Uruguay, Argentina, Chile), the Mediterranean (France, North Africa), Sub-Saharan Africa, Highland and Continental Plateaux (Tibetan Plateau/Mongolia/Atlas in Morocco), the mountainous regions of France, New Zealand and Vietnam, and the prairie area of Canada. A data base of 40 global grassland cases and a range of preferred practices have been compiled for these areas. A methodological framework is now available for assessing the contribution of grassland systems to multiple functions, along with the development of associated indicators that are aligned with the sustainable development goals (SDGs) - social, local development, production, economic and environmental. The framework has been built and tested using the global grassland cases. We present the results from three cases from Brazil, Vietnam and Argentina

P27Kip1, regulated by glycogen synthase kinase-3β, results in HMBA-induced differentiation of human gastric cancer cells

<p>Abstract</p> <p>Background</p> <p>Gastric cancer is the second most common cause of global cancer-related mortality. Although dedifferentiation predicts poor prognosis in gastric cancer, the molecular mechanism underlying dedifferentiation, which could provide fundamental insights into tumor development and progression, has yet to be elucidated. Furthermore, the molecular mechanism underlying the effects of hexamethylene bisacetamide (HMBA), a recently discovered differentiation inducer, requires investigation and there are no reported studies concerning the effect of HMBA on gastric cancer.</p> <p>Methods</p> <p>Based on the results of FACS analysis, the levels of proteins involved in the cell cycle or apoptosis were determined using western blotting after single treatments and sequential combinations of HMBA and LiCl. GSK-3β and proton pump were investigated by western blotting after up-regulating Akt expression by Ad-Akt infection. To investigate the effects of HMBA on protein localization and the activities of GSK-3β, CDK2 and CDK4, kinase assays, immunoprecipitation and western blotting were performed. In addition, northern blotting and RNase protection assays were carried out to determine the functional concentration of HMBA.</p> <p>Results</p> <p>HMBA increased p27Kip1 expression and induced cell cycle arrest associated with gastric epithelial cell differentiation. In addition, treating gastric-derived cells with HMBA induced G0/G1 arrest and up-regulation of the proton pump, a marker of gastric cancer differentiation. Moreover, treatment with HMBA increased the expression and activity of GSK-3β in the nucleus but not the cytosol. HMBA decreased CDK2 activity and induced p27Kip1 expression, which could be rescued by inhibition of GSK-3β. Furthermore, HMBA increased p27Kip1 binding to CDK2, and this was abolished by GSK-3β inhibition.</p> <p>Conclusions</p> <p>The results presented herein suggest that GSK-3β functions by regulating p27Kip1 assembly with CDK2, thereby playing a critical role in G0/G1 arrest associated with HMBA-induced gastric epithelial cell differentiation.</p

Projet TRANS. Rapport scientifique final du projet "Transformations de l'élevage et dynamiques des espaces" (Projet ANR-05-PADD-03)

The dynamics of change in livestock farming are central to the challenge of sustainable development in many territories in grassland and pastoral regions. The vitality of these territories is highly dependent on evolutions in livestock farming, which contribute to the evolution of the natural landscape that are basic to environmental issues. The purpose of this project is to have a new approach to changes in livestock farming and to connect these changes to the dynamics of natural areas. The studies will be based on five different site groups and on approaches that bring together agronomic sciences, social sciences and modelling. The work centred on the following five study groups: Amazonia, France, Pampa, Senegal and Vietnam. With the aim of renewing conceptual frameworks, TRANS studies interactions between transformations in farms, seen from the viewpoint of their diversity and their dynamics, and a vast collection of economic and political changes, as well as demographic pressure, competition between activities and the real estate aspects. The interest extends to collective actions carried out with and concerning livestock farmers, and in association with allies from outside the famers'world. It is relevant to operate all these characterizations because they have an influence on the evolution of land use. The first originality of TRANS therefore is that it takes into account all these interacting phenomena. The second feature stems from the consideration of diversity and the dynamics of systems. These aspects change in relation to conceptions of work and the job, composition of work collectives, combinations of activity, and the relation of farmers working in a situation of uncertainty. Faced with uncertainty for example, there are two long term logics. The first depends on a high level of technical control, whose indicator is a high level of production with a reasonable stocking level. The second ensures resistance to shocks by a) managing combinations of activities, or by b) having flexible systems relying on production processes (low stocking rate, several products marketed from the same herd ) contriving room for manoeuvre and adjustment options. This diversity of systems and the determinants of their dynamic make their mark on evolutions in land use. The models mobilized or developed in the project include these concepts at least partially. The third original feature stems from the "social" orientation. As livestock systems evolve, so do the farming society, composed of the farm holders as well as employees and other types of workers, and the "appropriate" farming style standards. In the end, the development of wage-earning appears as a strong indicator of transformations in how the livestock farming activity is practised, and it questions the future of the family farm. During the project, it was not possible to place all the results obtained in relationship with each other in a global model that connected changes in farms and land dynamics. However, a meta-model of the whole MAS (multi agents models) developed in the regions of the project approaches has been produced. But the influence of collective actions on land use dynamics, and the elements characterizing the diversity of livestock farms (composition of work collectives, conceptions of the work) were not very much integrated into the total modelling approach. The models take account of changes of land use, with explicit consideration of the area, but only very partially describe the associated ecological dynamics (encroaching scrubland, loss of biodiversity ), which should be carried out in the continuity of the work. A thorough bibliography of scenario methods was created. However, on part of the lands, there was no time for participative implementation of the scenario test. In the end, all of these scientific reflections were placed at the service of three operational developments: 1) within the framework of participative approaches, simulators and scenarios of change were developed, that could be used for dialogue and debates between players in the territories, to visualize the effect of these scenarios on changes in livestock farming and, the landscape produced; 2) TRANS initiated a reflection on strategic advice in livestock farming, renewed by integrating a vision of uncertainty creating possible future problems in the medium and long term, and 3) made it possible to fill out an « advice-work » corpus and make it operational.Les dynamiques de changement des activités d'élevage se trouvent au c½ur des enjeux de développement durable de nombreux territoires dans les régions herbagères et pastorales. La vitalité de ces territoires dépend fortement des évolutions de l'élevage d'herbivores, qui participent à l'évolution des espaces naturels, supports d'enjeux environnementaux. Le projet Trans vise à renouveler les façons d'aborder les transformations de l'élevage et à relier ces transformations aux dynamiques des espaces naturels en s'appuyant sur cinq terrains différents, et sur des approches associant sciences agronomiques, sciences sociales et modélisation. Le travail a porté sur les cinq grands terrains choisis (Amazonie brésilienne, France, Pampa, Sénégal, Vietnam). Trans étudie les interactions entre la transformation des exploitations et un vaste ensemble de changements : changements de politique, mais aussi pressions démographiques, concurrences entre activités d'élevage et autres activités (forêt, culture) et aspects de politique foncière. L'intérêt s'étend aux actions collectives menées avec et autour des éleveurs, et en lien avec des alliés. Il est pertinent d'opérer toutes ces caractérisations parce qu'elles jouent sur les évolutions des modes d'utilisation de l'espace. Le premier trait d'originalité de Trans est donc la prise en compte de tous ces phénomènes en interaction, pour expliquer les transformations de l'élevage et leurs liens aux changements d'utilisation des espaces. Le second trait tient au regard porté sur la diversité et la dynamique des systèmes. Les systèmes se transforment en relation avec les conceptions de métier et de travail, la composition des collectifs de travail, les combinaisons d'activité, le rapport des exploitants à l'action en situation d'incertitude. Face à l'incertitude par exemple, il existe deux logiques de long terme. La première se joue autour d'un haut niveau de maîtrise technique (dont l'indicateur est un niveau de production élevé avec un niveau de charge raisonnable), la seconde assure la résistance aux chocs par la conduite de combinaisons d'activités, ou par une flexibilité des systèmes reposant sur les régulations des processus de production (faible chargement, plusieurs produits commercialisés à partir d'un même troupeau ) ménageant des marges de man½uvre et des options d'ajustement. Cette diversité des systèmes et les déterminants de leurs dynamiques marquent les évolutions de l'utilisation de l'espace. Les modèles mobilisés ou développés dans le projet incluent au moins partiellement ces concepts. Le troisième trait original tient à l'orientation "sociale". En même temps qu'évoluent les systèmes d'élevage, se transforment aussi 1) la « société d'éleveurs » (le monde des éleveurs) composée de chefs d'exploitation mais aussi de salariés et d'autres types d'intervenants, 2) les normes de l'élevage "qui convient". Le développement du salariat apparaît comme un indicateur des transformations des formes d'exercice de l'activité d'élevage et interroge le devenir de l'exploitation familiale. Dans le temps du projet, il n'a pas été possible de mettre en relation l'ensemble des résultats obtenus dans un modèle global reliant transformations des élevages et dynamiques des espaces. Cependant, un méta-modèle issu de l'ensemble des démarches SMA (systèmes multiagents) développées dans les différents terrains du projet a été produit. Mais l'influence des actions collectives sur les dynamiques des espaces et les éléments de caractérisation de la diversité des exploitations (composition des collectifs de travail, conceptions de métiers) ont été encore peu intégrés dans les démarches de modélisation globale, en dépit d'avancées significatives relatives à la prise en compte des trajectoires sur le long terme des exploitations ou des questions de travail dans ces modèles. Les modèles rendent compte de changements d'utilisation du territoire, avec un regard spatialement explicite, mais décrivent encore très partiellement les dynamiques écologiques associées (enfrichement, perte de biodiversité ), ce qui devrait être réalisé dans le prolongement des travaux. Un approfondissement bibliographique des méthodes de scénarios a été réalisé. Cependant, sur une partie des terrains, le temps a manqué pour une mise en ½uvre participative du test de scénarios. Au final, l'ensemble de ces réflexions scientifiques a été mis au service de trois développements opérationnels : 1) dans le cadre d'approches participatives, ont été développés des simulateurs et des scénarios de changement, utilisables pour le dialogue entre acteurs des territoires, afin de visualiser et débattre de l'effet de ces scénarios sur les transformations de l'élevage et sur les espaces produits ; 2) Trans a initié une réflexion sur le conseil stratégique en élevage, renouvelé par l'intégration d'une vision de l'incertitude pesant sur l'avenir à moyen et long terme, et 3) a permis d'étoffer et d'opérationnaliser un corpus « conseil-travail »

Entre local et global: quelles reconfigurations dans les bassins laitiers ? Analyse comprative d'étude de cas du Nord et du Sud

International audienceBetween globalization and territorialisation, milk sector is changing. For instance, since World War II we can notice in Western Europe a decreasing of small size farms and of small processing units. In the same time very large enterprises have developed, taking advantage of the world wide dimension of agro- food systems and new technologies. As a consequence the distance is increasing between products, farming activities and territories. However, in some areas, local agri-food systems maintained, taking advantage of an organizational, geographical or cultural proximity between local actors and of the increasing concerns on proximity, locality or heritage. As a consequence we notice, in some Dairy Basins, different ways of reorganization in agro-food systems concerning both livestock farming systems and processing firms toward territorial roots of their products. Globalization and localization of fluxes are in action in dairy industry. How do these processes appear and express themselves within the territories? Which expression and consequences on changes in farming systems? May we see some synergies or oppositions between these processes? To answer these interrogations our research is based on the analysis of the ways these changes have been operating in seven Dairy Basins in France (3), Southern America (Uruguay, Brazil), Western Africa (Senegal) and South Eastern Asia (Vietnam). We consider the Dairy Basin as the territory where these dynamics express and interact. Our approach is based on a diachronic analysis of changes operating in Dairy Basins since the middle XXth century: changes in marketing strategies of firms as well as in livestock farming practices, (re) localization of these activities, local dynamics within the studied area, time matches with major events. These chronicles constitute an intermediate object, allowing the understanding of the ways food chains/livestock farming systems/territories interact as well as they co-evolve along the time. From a comparative analysis of these case studies we will identify emerging conditions and ways of expression of these “glocalisations” processes and the main drivers of changes according the context they are embedded in