20 research outputs found
Oil Exports, Political Issues, and Stock Market Nexus
This study investigates the influence of oil export and political issues on Iraq's stock exchange using various Ordinary Least Square regression models. The empirical results show that the model's effect is not similar based on the explanatory variables included, such as the Covid-19 outbreak, financial crisis, parliament elections, and ISIS emergence are not significant. In contrast, the internal conflict, oil export, and oil prices are substantial effects on the index of the Iraq stock exchange from (2004 to 2021); researchers in the literature have neglected this market due to its novel establishment after (2003). Moreover, the market capitalization still considers very small compared to the regional financial markets. The study contributes to the existing knowledge because most studies on stock market determinants consider political, economic, democratic, or governmental factors. In contrast, here, most elements included using new measurements, such as the internal conflict by cutting off the financial share of the Kurdistan region from the central state budget. Finally, the analysis incorporates the conclusions with straightforward suggestions that policymakers can use, government, investors, and supervisors to control the stock market risk.Â
Achieving a nature- and people-positive future
Despite decades of increasing investment in conservation, we have not succeeded in “bending the curve” of biodiversity decline. Efforts to meet new targets and goals for the next three decades risk repeating this outcome due to three factors: neglect of increasing drivers of decline; unrealistic expectations and time frames of biodiversity recovery; and insufficient attention to justice within and between generations and across countries. Our Earth system justice approach identifies six sets of actions that when tackled simultaneously address these failings: (1) reduce and reverse direct and indirect drivers causing decline; (2) halt and reverse biodiversity loss; (3) restore and regenerate biodiversity to a safe state; (4) raise minimum wellbeing for all; (5) eliminate over-consumption and excesses associated with accumulation of capital; and (6) uphold and respect the rights and responsibilities of all communities, present and future. Current conservation campaigns primarily address actions 2 and 3, with urgent upscaling of actions 1, 4, 5, and 6 needed to help deliver the post-2020 global biodiversity framework
Safe and just Earth system boundaries
The stability and resilience of the Earth system and human well-being are inseparably linked 1-3, yet their interdependencies are generally under-recognized; consequently, they are often treated independently 4,5. Here, we use modelling and literature assessment to quantify safe and just Earth system boundaries (ESBs) for climate, the biosphere, water and nutrient cycles, and aerosols at global and subglobal scales. We propose ESBs for maintaining the resilience and stability of the Earth system (safe ESBs) and minimizing exposure to significant harm to humans from Earth system change (a necessary but not sufficient condition for justice) 4. The stricter of the safe or just boundaries sets the integrated safe and just ESB. Our findings show that justice considerations constrain the integrated ESBs more than safety considerations for climate and atmospheric aerosol loading. Seven of eight globally quantified safe and just ESBs and at least two regional safe and just ESBs in over half of global land area are already exceeded. We propose that our assessment provides a quantitative foundation for safeguarding the global commons for all people now and into the future
Safe and just Earth system boundaries
The stability and resilience of the Earth system and human well-being are inseparably linked1-3, yet their interdependencies are generally under-recognized; consequently, they are often treated independently4,5. Here, we use modelling and literature assessment to quantify safe and just Earth system boundaries (ESBs) for climate, the biosphere, water and nutrient cycles, and aerosols at global and subglobal scales. We propose ESBs for maintaining the resilience and stability of the Earth system (safe ESBs) and minimizing exposure to significant harm to humans from Earth system change (a necessary but not sufficient condition for justice)4. The stricter of the safe or just boundaries sets the integrated safe and just ESB. Our findings show that justice considerations constrain the integrated ESBs more than safety considerations for climate and atmospheric aerosol loading. Seven of eight globally quantified safe and just ESBs and at least two regional safe and just ESBs in over half of global land area are already exceeded. We propose that our assessment provides a quantitative foundation for safeguarding the global commons for all people now and into the future
Linking above- and belowground phenology of hybrid walnut in temperate agroforestry systems
L’étude de la phénologie des plantes est primordiale pour comprendre leur réponse aux changements globaux. Alors que de nombreuses études ont été consacrées à la phénologie aérienne, les difficultés d’observations de la phénologie des parties sou terraines d’une plante, font que leurs déterminants sont encore trop peu connu. La dynamique racinaire est considérée comme jouant un rôle clef dans le cycle et la séquestration du carbone dans le sol, et il est aujourd’hui important de surmonter les difficultés méthodologiques afin de mener des études sur la dynamique racinaire sur plusieurs années en conditions non-contrôlées. Notre premier objectif ici était donc de mettre au point et d’évaluer différentes techniques d’observation de la croissance racinaire sur le terrain. Le modèle choisi pour cela est le noyer hybride (Juglans L.), en système agroforestiers. L’utilisation du scan incorporé au smartphone s’est avéré être le meilleur compromis pour l’acquisition d’image à partir de rhizotrons, excepté en cas d’automatisation de la prise d’images, où la caméra automatique constitue la meilleur alternative (jusqu’à 4 mois d’autonomie). Notre deuxième objectif était de déterminer en milieu naturel les facteurs prédominants de la dynamique racinaire. Nous avons en particulier (i) testé l’hypothèse de la synchronicité des phénologies aériennes et racinaires de la plante, (ii) évalué l’effet de fluctuations climatiques sur la dynamique racinaire dans des environnements contrastés (climats méditerranéen, océanique, continental), (iii) et cherché à comprendre si cette réponse aux facteurs externes était conditionnée par la typologie racinaire. Les résultats ont permis de montrer l’indépendance des phénologies aériennes et racinaires, mais la synchronisation des croissances racinaires et radiale du tronc. Le principal facteur influençant la dynamique racinaire est la température du sol, et à moindre mesure l’humidité du sol avec des effets contrastés selon le climat. Les réponses des dynamiques racinaires aux variables environnementales sont propres à chaque site, avec un fort impact de l’ordre topologique sur les taux d’initiation et de survie. Ces résultats permettront non seulement une meilleur compréhension du jouait par les systèmes racinaires sur le cycle du carbone, mais aussi l’amélioration des modèles écophysiologiques. De futurs études sont néanmoins nécessaires d’autres études sont attendues pour renforcer les connaissances acquises dans ce projet, sur la compréhension des déterminants de l’initiation, de la croissance, et de la longévité racinaire des arbres, notamment via la création de bases de données et l’utilisation de méta-analyses.The study of phenology is primordial to understand tree response to climate change. Although many studies have examined shoot phenology, the difficulties in observing root system growth have resulted in a poor understanding of root phenology. As root system dynamics are considered as playing a major role in carbon cycling and sequestration, it is necessary to overcome methodological difficulties, so that root demography can be studied in the field and over several years. Our first objective was therefore to develop and evaluate methods for studying root system growth in the field. Studying mature hybrid walnut (Juglans L.), growing in agroforests, We showed that smartphone scanners are the best adapted tool for acquiring high quality images of tree roots growing in field rhizotrons. However, time-lapse cameras were good alternatives when a fully automated method was required (up to 4 months autonomy). Our second objective was to determine the main drivers of walnut hybrid root growth in field conditions. In particular, (i) We hypothesized that shoot and root phenologies were asynchronous, (ii) We evaluated the effect of environmental factors on root growth along a latitudinal gradient comprising three climates (Mediterranean, oceanic and continental) and (iii) We determined how phenology and environmental factors influenced root dynamics depending on root morphology and topology. Results show that flushes of fine root growth are not synchronized with budburst and leaf expansion, but are synchronized with stem and coarse root radial growth. Soil temperature was on the whole the main driver of root growth, and to a lesser extent, soil humidity, but which had contrasting effects on root growth. Root topological order had a major influence on root response to environmental variables, reflected in root elongation, production and longevity. Results will be highly useful not only for a better understanding of the role that root systems play in the carbon cycle, but also for tree ecophysiological models. Future studies should expand the knowledge gained here into a global understanding of the drivers of tree root initiation, growth and longevity, through the creation of databases and the use of meta-analyses
Relations entre phénologie de la croissance souterraine et aérienne de noyers hybrides en systèmes agroforestiers tempérés
The study of phenology is primordial to understand tree response to climate change. Although many studies have examined shoot phenology, the difficulties in observing root system growth have resulted in a poor understanding of root phenology. As root system dynamics are considered as playing a major role in carbon cycling and sequestration, it is necessary to overcome methodological difficulties, so that root demography can be studied in the field and over several years. Our first objective was therefore to develop and evaluate methods for studying root system growth in the field. Studying mature hybrid walnut (Juglans L.), growing in agroforests, We showed that smartphone scanners are the best adapted tool for acquiring high quality images of tree roots growing in field rhizotrons. However, time-lapse cameras were good alternatives when a fully automated method was required (up to 4 months autonomy). Our second objective was to determine the main drivers of walnut hybrid root growth in field conditions. In particular, (i) We hypothesized that shoot and root phenologies were asynchronous, (ii) We evaluated the effect of environmental factors on root growth along a latitudinal gradient comprising three climates (Mediterranean, oceanic and continental) and (iii) We determined how phenology and environmental factors influenced root dynamics depending on root morphology and topology. Results show that flushes of fine root growth are not synchronized with budburst and leaf expansion, but are synchronized with stem and coarse root radial growth. Soil temperature was on the whole the main driver of root growth, and to a lesser extent, soil humidity, but which had contrasting effects on root growth. Root topological order had a major influence on root response to environmental variables, reflected in root elongation, production and longevity. Results will be highly useful not only for a better understanding of the role that root systems play in the carbon cycle, but also for tree ecophysiological models. Future studies should expand the knowledge gained here into a global understanding of the drivers of tree root initiation, growth and longevity, through the creation of databases and the use of meta-analyses.L’étude de la phénologie des plantes est primordiale pour comprendre leur réponse aux changements globaux. Alors que de nombreuses études ont été consacrées à la phénologie aérienne, les difficultés d’observations de la phénologie des parties sou terraines d’une plante, font que leurs déterminants sont encore trop peu connu. La dynamique racinaire est considérée comme jouant un rôle clef dans le cycle et la séquestration du carbone dans le sol, et il est aujourd’hui important de surmonter les difficultés méthodologiques afin de mener des études sur la dynamique racinaire sur plusieurs années en conditions non-contrôlées. Notre premier objectif ici était donc de mettre au point et d’évaluer différentes techniques d’observation de la croissance racinaire sur le terrain. Le modèle choisi pour cela est le noyer hybride (Juglans L.), en système agroforestiers. L’utilisation du scan incorporé au smartphone s’est avéré être le meilleur compromis pour l’acquisition d’image à partir de rhizotrons, excepté en cas d’automatisation de la prise d’images, où la caméra automatique constitue la meilleur alternative (jusqu’à 4 mois d’autonomie). Notre deuxième objectif était de déterminer en milieu naturel les facteurs prédominants de la dynamique racinaire. Nous avons en particulier (i) testé l’hypothèse de la synchronicité des phénologies aériennes et racinaires de la plante, (ii) évalué l’effet de fluctuations climatiques sur la dynamique racinaire dans des environnements contrastés (climats méditerranéen, océanique, continental), (iii) et cherché à comprendre si cette réponse aux facteurs externes était conditionnée par la typologie racinaire. Les résultats ont permis de montrer l’indépendance des phénologies aériennes et racinaires, mais la synchronisation des croissances racinaires et radiale du tronc. Le principal facteur influençant la dynamique racinaire est la température du sol, et à moindre mesure l’humidité du sol avec des effets contrastés selon le climat. Les réponses des dynamiques racinaires aux variables environnementales sont propres à chaque site, avec un fort impact de l’ordre topologique sur les taux d’initiation et de survie. Ces résultats permettront non seulement une meilleur compréhension du jouait par les systèmes racinaires sur le cycle du carbone, mais aussi l’amélioration des modèles écophysiologiques. De futurs études sont néanmoins nécessaires d’autres études sont attendues pour renforcer les connaissances acquises dans ce projet, sur la compréhension des déterminants de l’initiation, de la croissance, et de la longévité racinaire des arbres, notamment via la création de bases de données et l’utilisation de méta-analyses
Linking above-and belowground phenology of hybrid walnut in temperate agroforestry systems
Linking above-and belowground phenology of hybrid walnut in temperate agroforestry systems. 3rd European Agroforestry Conferenc
Agroforestry: tree roots impact on soil microorganisms
Agroforestry: tree roots impact on soil microorganisms. EcoSummit 2016 Ecological Sustainability: Engineering Chang
Slow recovery from soil disturbance increases susceptibility of high elevation forests to landslides
International audienceNatural hazards such as shallow landslides are common phenomena that disturb soil and damage forests. Quantifying the recovery of forest vegetation after a hazard is important for determining the window of susceptibility to new disturbance events, especially at high elevations, where extreme weather events are frequent and the growing season is short. Plant roots can reduce the size of this window on unstable hillslopes, by adding mechanical reinforcement (cr) to soil and increasing its matric suction, termed here as hydrological reinforcement (ch). These data are used in landslide models to calculate the Factor of Safety (FoS) of a hillslope. We calculated temporal variations in cr and ch in naturally regenerated mixed, montane forests in the French Alps. In these closed-canopy forests, open-canopy gaps were present, with understory vegetation comprising herbs, forbs and shrubs. At three altitudes (1400, 1700 and 2000 m), we dug small trenches as proxies for shallow landslide events and calculated cr before soil disturbance in both open gaps and closed forests. Then, using monthly tree root initiation and mortality data measured in rhizotrons, we calculated monthly cr for four years after the disturbance. To compare results with cr, ch was estimated using matric suction data that were measured in trenches at 1400 m for >1 year. Temporal FoS was then calculated using an infinite slope stability model.Results showed that finer, short-lived roots contributed little to soil reinforcement compared to thicker, long-lived roots. After disturbance, mean cr (over the entire soil profile) never fully recovered to the initial value at any site, although >90% recovery was observed in open gaps at 1400 m. Mean cr was slow to recover in closed forests, especially at 2000 m, where only 19% recovery occurred after 41 months. The ch in closed forests was considerable during the summer months, but marked increases in soil water moisture resulted in lower FoS, especially during December to April, when soil was near saturation. As cr changed little throughout the year, it was a more reliable contributor to slope stability. Our results show therefore, that particular attention should be paid to high elevation forests after a disturbance. Also, during the process of recovery, the highly variable soil water dynamics in closed forest can result in seasonal hotspots of vulnerability. Therefore, when tree transpiration is low, our results highlight a need for careful monitoring on steep or unstable slopes, especially in disturbed closed-canopy forest