Climate Stability Research Articles

Consistent growth responses of silver fir (Abies alba Mill.) and European beech (Fagus sylvatica L.) to drought in mixed and monospecific forests: Insights from Central European forests

Ongoing climate change, characterized by an increased frequency of extreme weather events, including severe droughts, negatively impacts forest ecosystems. However, tree responses differ across tree species and stand composition (mixtures vs. pure stands), which may serve as an important management strategy for forest adaptation to climate change. To investigate the effect of stand composition on drought resilience, we conducted research on forest ecosystems in the Polish Outer Carpathians at the eastern edge of the distribution range of two important European tree species, silver fir (Abies alba) and European beech (Fagus sylvatica). The aim of our study was to identify climatic factors influencing the growth of these species and to examine their drought sensitivity and productivity. For this purpose, we sampled 100 fir and 100 beech trees from both mixed and monospecific stands. We applied a dendroclimatological approach to determine temporal stability of climate–growth relationships. Lloret’s resilience indices were used to quantify the response of tree growth to episodic drought stress, while to derive differences in productivity, we applied the generalized additive mixed models (GAMMs). Our results showed species specific climate sensitivity which remain consistent regardless of mixture only for fir. Fir responded positively to higher temperatures, especially during spring, but required more precipitation, particularly in summer. Beech exhibited lower sensitivity to climate in mixed than in monospecific stands and exhibited higher resistance than fir. Importantly, species responses to droughts were driven by the duration of specific drought event and the timing in which it occurred. Furthermore, our results revealed that mixed stands were more resistant to extreme drought events. Fir showed higher resistance to extreme drought events in mixed stands than in pure stands. Overall, silver fir exhibited higher productivity than European beech. Especially in younger cohorts, it was higher for pure stands, but fir from mixed stands exhibited increasing productivity with age and delayed culmination. Our findings indicate that both species can form resilient stands in the studied region, making them viable for forest management in the face of climate change. Mixtures of fir and beech are particularly valid option to promote forest sustainability and productivity in mountain regions. Managed mixed stands of Abies alba and Fagus sylvatica demonstrated advantages in productivity and stability under extreme drought conditions. However, varying intensities of management interventions and structural differences between stands and among studies complicate direct comparisons, highlighting the need for more standardized approaches to analyzing species responses and management strategies in the future.

Democracy and Climate Change for Realists: An Integrated Empirical and Normative Assessment

Abstract When scholars consider the relation between domestic political regimes and global climate change, they typically rely on assumptions about liberal democracy's core competencies with respect to environmental protection in general. As a result, an ostensibly normative debate pitting democracy against “eco-authoritarianism” depends for its resolution on causal theory and empirical analysis. I offer an integrated assessment of both empirical (causal) and normative (ethical) theories on democracy, autocracy, and climate change, concluding that democracy's superiority is less compellingly supported than regime-neutrality. Theoretically, the causal logic of environmentally protective democracy cannot readily be extended to climate change as a distinctive political problem. Empirically, my review of global statistical analyses of regime type and climate change reveals that the evidence is more consistent with regime-neutrality than democratic advantage. Regime-neutrality, in turn, revitalizes difficult normative arguments about trade-offs between democratic freedom and climatic stability. Something resembling the “win-win” situation of climate-fixing democracy may still be salvaged, theoretically. But political science's search for this outcome should take a realist turn: abandoning the liberal-authoritarian dichotomy in favor of a new one, pitting post-liberal forms of democracy against climate-fixing hybrid regimes.

Multicentennial cycles in continental demography synchronous with solar activity and climate stability

Human population dynamics and their drivers are not well understood, especially over the long term and on large scales. Here, we estimate demographic growth trajectories from 9 to 3 ka BP across the entire globe by employing summed probability distributions of radiocarbon dates. Our reconstruction reveals multicentennial growth cycles on all six inhabited continents, which exhibited matching dominant frequencies and phase relations. These growth oscillations were often also synchronised with multicentennial variations in solar activity. The growth cycle for Europe, reconstructed based on >91,000 radiocarbon dates, was backed by archaeology-derived settlement data and showed only a weak correlation with mean climate states, but a strong correlation with the stability of these states. We therefore suggest a link between multicentennial variations in solar activity and climate stability. This stability provided more favourable conditions for human subsistence success, and seems to have induced synchrony between regional growth cycles worldwide.

Lateglacial and Holocene chronology of climate‐driven postglacial landscape evolution in northeast Greenland

The Greenland Ice Sheet is highly sensitive to climate change, leading to significant retreat along its edges. This rapid ice loss contributes to rising sea levels and impacts the Earth's climate stability. Understanding the extent of recent glacier retreat is crucial in order to determine if it is unprecedented or within ranges of natural variability. Palaeoenvironmental studies aim to identify past glacial phases and landscape changes using advanced dating methods such as cosmic ray exposure (CRE) dating. In NE Greenland, CRE dating has helped establish the timing of glacial oscillations, yet a comprehensive understanding of glacial fluctuations during specific periods still needs to be developed. This study aims to chronologically constrain the postglacial landscape evolution of two NE Greenland valleys from the Young Sund–Tyrolerfjord area (74°N, 20–25°E) from the onset of deglaciation and throughout the Holocene to better understand glacial and postglacial changes. The chronological framework relies on 27 10Be cosmic‐ray exposure ages that constrain our interpretation of the geomorphological features in both valleys. Inconsistencies were observed in the ages dataset, highlighting potential bias associated with nuclide inheritance and post‐glacial dynamics. Despite limitations, the CRE results confirm the general pattern observed in NE Greenland: (i) major deglaciation and disconnection of glaciers from the main glacial systems during the Lateglacial and Early Holocene with a rapid but not homogeneous deglaciation within the range from ~14.3 to 11.9 ka; (ii) no evidence of glacial activity during the Middle Holocene, probably associated with the withdrawn position of the ice masses’ fronts; and (iii) glacier expansion during the Late Holocene, with a Little Ice Age advance as the last significant period of glacial regrowth.

Political cycles, fiscal policy and capital flight in Africa

PurposeThis paper examined the interactive role of Political Cycles on the relationship between Fiscal Policy and Capital Flight in Africa.Design/methodology/approachA two-step System Generalized Methods of Moment empirical estimator was employed. This study used data on 40 African countries from 2009 to 2018.FindingsThe findings revealed that the interaction between political structures and fiscal policy is positive and significant, indicating that fiscal policies during election periods or different regimes would increase capital flight. The study found that political cycles positively affect capital flight, indicating that election periods and possible government changes promote capital flight activities. The tension and volatile atmosphere characterizing election periods in most African countries cause investors to use all alternatives, including illegal systems, to fly funds to a potentially stable economy.Practical implicationsThis study recommends that government and policymakers maintain fiscal discipline during election years and enact pragmatic policies to ensure the continuity of critical fiscal policies to promote business climate and economic stability, especially when there is a change in government.Originality/valueThis study contributes to capital flight literature in two forms. One, the study, to the best knowledge of the authors, is the first to proxy tax with corporate tax (a sound proxy for tax within the business space). Also, this study is the first to empirically show that elections worsen the effect of fiscal policy on capital flight in Africa.Peer reviewThe peer review history for this article is available at: https://publons.com/publon/10.1108/IJSE-02-2024-0130

Development and conservation in the tropical forest frontier: a 50-year analysis of policy evolution and interplay in Marqués de Comillas, Chiapas, México

ABSTRACT Tropical forests are vital for global biodiversity and climate stability, but the political economy of deforestation and land-use change constantly challenges their integrity. In this article, we analyse 50 years of policy development in the municipality Marqués de Comillas, located in Selva Lacandona, Chiapas, Mexico, to understand how development and conservation priorities have evolved, interacted, and shaped land-use in a tropical forest frontier. By analysing peer-reviewed literature and empirical data, we identify five phases of policy continuity and change that have produced diverse socio-environmental outcomes. We reveal a persistent state-led prioritisation of rural development over environmental concerns, pursued through policies promoting settlements and agricultural expansion and exacerbated by external market forces. This focus has caused substantial ecosystem degradation and deforestation without significant livelihood improvements. Recent conservation initiatives, such as payment for ecosystem services, show potential for challenging the status quo by offering alternative livelihood opportunities benefiting both people and ecosystems.

Land-use competition in 1.5°C climate stabilization: is there enough land for all potential needs?

Achieving a low-carbon future requires a comprehensive approach that combines emission mitigation options from economic activities with the sustainable use of land for numerous needs: food production, energy production, carbon sequestration, nature preservation and broad ecosystem services. Using the MIT Integrated Global System (IGSM) framework we analyze land-use competition in a 1.5°C climate stabilization scenario, in which demand for bioenergy and natural sinks increase along with the need for sustainable farming and food production. We find that to address the numerous trade-offs, effective approaches to nature-based solutions (NBS) and agriculture practices are essential. With proper regulatory policies and radical changes in current practices, global land is sufficient to provide increased consumption of food per capita (without large diet changes) over the century while also utilizing 2.5–3.5 billion hectares (Gha) of land for NBS practices that provide a carbon sink of 3–6 gigatonnes (Gt) of CO2 per year as well as 0.4–0.6 Gha of land for energy production—0.2–0.3 Gha for 50–65 exajoules (EJ) per year of bioenergy and 0.2–0.35 Gha for 300–600 EJ/year of wind and solar power generation. We list the competing uses of land to reflect the trade-offs involved in land use decisions, and note that while there is sufficient land in our scenario, attaining this outcome, capable of delivering a 1.5°C future, requires effective policies and measures at national and global levels that promote efficient land use for food, energy and nature (including carbon sequestration) and ensure long-term commitments by decision makers from governments and industry in order to realize the benefits of climate change mitigation.

Hydrological changes and its impacts on prehistoric human welfare in the western Tibetan Plateau since the last deglaciation

In recent decades, the rapidly changing climate environment in the Tibetan Plateau (TP) poses significant challenges to human survival and future sustainable development. The suitability and stability of the climate in the TP undoubtedly affected the living conditions and welfare of prehistoric humans. However, few studies have attempted to link climate stability and the survival of ancient humans, especially considering their lesser adaptability in responding to rapid environmental changes. The Xiada Co is a Neolithic period archaeological site in the western TP. In this study, we reconstructed the hydrological changes in the basin over the past 15,000 years using X-ray fluorescence (XRF) elemental analysis on the Xiada Co cores. The XRF results revealed three main paleoenvironmental units during the entire study interval. The late Pleistocene prior to ~10,000 cal year BP was characterized by more rapidly fluctuating hydrologic conditions. The early and middle Holocene (~10,000–4000 cal year BP) by stable hydrologic conditions, and the late Holocene to present by a return to more variable conditions. Using the calculation method of Square Chord Distance (SCD), a quantitative dissimilarity comparison was made regarding the climate variations in the western TP for 15 time periods. The results showed that the climate and hydrology were relatively stable during the period of occupation of the region (8500–7500 years BP), which provided a stable and suitable living environment for the hunter-gatherers at the site. This study illustrates how the paleoenvironment influenced the survival of hunter-gatherers in the extremely harsh western TP.

Laser ablation inductively coupled plasma mass spectrometry measurements for high-resolution chemical ice core analyses with a first application to an ice core from Skytrain Ice Rise (Antarctica)

Abstract. Conventional methods of inorganic impurity analysis do not provide high enough depth resolution for many scientific questions in ice core science. In this study, we present a setup of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for high-resolution glacier ice impurity analysis to the sub-millimetre scale. This setup enables ice core chemical impurity analysis to a depth resolution of ∼182 µm while consuming only very small amounts of ice. The system performs simultaneous analysis of sodium, magnesium and aluminium incorporated in the ice matrix. In this case study within the framework of the WACSWAIN (WArm Climate Stability of the West Antarctic Ice Sheet in the last INterglacial) project, our method is applied to a selection of samples from the Skytrain ice core (West Antarctica) over a total length of 6.7 m consisting of about 130 single samples. The main goal of this study is to use the new LA-ICP-MS method to extract meaningful climate signals on a depth resolution level beyond the limits of continuous-flow analysis (CFA). A comparison between low-resolution CFA data and the high-resolution LA-ICP-MS data reveals generally good agreement on the decimetre scale. Stacking of parallel laser measurements together with frequency analysis is used to analyse the high-resolution LA-ICP-MS data at millimetre resolution. Spectral analysis reveals that despite effects of impurity accumulation along ice crystal grain boundaries, periodic concentration changes in the Skytrain ice core on the millimetre scale can be identified in ice from 26.8 ka (kiloyears before present, i.e. 1950 CE). These findings open new possibilities for climate data interpretation with respect to fast changes in the last glacial period and beyond, for example within the Beyond EPICA oldest-ice project.

Sea-level changes and human economic development in the northern flank of the Yangtze River Delta during the Middle to Late Holocene

The environmental dynamics in coastal regions are inevitably influenced by fluctuations in sea levels and human interventions. Evidence derived from archeological site remains and sediment cores indicates that sea-level change has been the primary driving force behind the continuous relocation of human settlements since the Holocene epoch. However, the understanding of the Holocene land formation process and its relationship with human activities in the northern flank of the Yangtze River Delta remains limited. The Guoqing Temple, located in southwest Juegang and serving as a hub for sea salt production during the Sui and Tang Dynasties, was established in the Tang Dynasty and served as one of the pivotal points along the Maritime Silk Road. A sedimentary core was obtained in close to the Guoqing Temple, and the sedimentological and micropalaeontological data were analyzed to investigate the process of sedimentary evolution from marine to terrestrial environments, as well as the environmental factors facilitating the development of the salt industry. Analysis results explained that: Between 6360 and 1750 cal yr BP, the study area was situated in a shallow sea on the outermost periphery of the sandbank, with a maximum water depth of 20 m. After 1750 cal yr BP, it underwent a transition to a supratidal low-salinity shallow marsh environment that continued to be influenced by marine conditions. The climate in the study area is primarily influenced by the Asian monsoon: Before 3000 cal yr BP, the overall climatic conditions were characterized by warm and humid conditions; After 3000 cal yr BP, climate stability prevailed in the region. Meanwhile, due to the newly formed wetlands that facilitated extensive salt production, economic shifts toward southern regions, and reforms in salt laws during the Tang Dynasty, Juegang emerged as a flourishing commercial trade hub and a prosperous center for Buddhist culture.

Radiocarbon dating and isotopic paleoecology of Notiomastodon platensis (Mammalia: Proboscidea) from the late Pleistocene of Minas Gerais, Brazil

Proboscidea is a group of large mammals abundant in the fossil record and in Brazil it is represented by Notiomastodon platensis (Ameghino, 1888). To improve the understanding on its taxonomy, chronology, annual diet, and habitats paleoenvironmental aspects, we conducted a morphological description, absolute dating, and analysis of stable isotopes of carbon and oxygen (δ13C and δ18O) in Notiomastodon' remains from the northern (Norte de Minas) and western (Triângulo Mineiro) mesoregions of Minas Gerais State, Brazil. The material includes isolated teeth, mandibular portions, and postcranial bones at different levels of fragmentation, associated with at least eight adults and one juvenile. The only individual from Triângulo, found in Campina Verde municipality, was dated at 27,715–27,903 Cal yr BP. It presented a mixed diet based on C4 plants (piC4 = 90 %; δ13C = 0.5 ‰), which implies the occupation of an open environment, mostly pasture. The region was relatively humid (δ18O = 24.7 ‰), which is supported by the existence of humidity corridors in the Amazon region. A similar phytophysiognomy was inferred for the Norte de Minas region between at least 21,966–22,279 Cal yr BP and 18,944–19,157 Cal yr BP. However, one specimen showed a different δ13C value (piC3 = 0.87 %; δ13C = −10.2 ‰). This indicates it lived in a transitional environment between low-density forest and arboreal savannah. This likely occurred during a period that favored the expansion of trees and shrubs. The region underwent climate change, from relatively humid conditions (δ18O = 25.6 ± 0.2 ‰) to expressively dry (δ18O = 34.6 ‰) between the dated periods, a change corroborated by some palynological data. The multiannual paleoecological analysis, based on sequential sampling of three dentin layers of an incisor, indicated the relative stability of vegetation and climate despite fluctuations in hydrology. The perceived disassociation between vegetation dynamics and local hydrology corroborates the idea that factors other than precipitation may play a significant role in the environmental dynamics of the Cerrado biome.

Geographic Gradients in Species Interactions: From Latitudinal Patterns to Ecological Mechanisms

The idea that species interactions are more ecologically and evolutionarily important toward lower latitudes underpins seminal theories in ecology and evolution. Recent global studies have found the predicted latitudinal gradients in interactions, particularly predation. However, latitudinal patterns alone do not reveal why interactions vary geographically and so do not provide strong predictions in space (e.g., for specific ecosystems) or time (e.g., forecasting responses to global change). Here, I review theory to identify a clearer, mechanistic, and testable framework for predicting geographic variation in the importance of species interactions. I review competing metrics of importance, proximate mechanisms that can increase interaction importance, and environmental gradients that could generate predictable geographic patterns (climate extremes and stability, warmer temperatures, productivity, and biodiversity). Strong empirical tests are accumulating thanks to the rise of global experiments and datasets; renewed focus on testing why interactions vary spatially will help move the field from identifying latitudinal patterns to understanding broader mechanisms.

A global overview of insect-fern interactions and its ecological trends.

Historically, ferns have been described as underutilized by insects. However, studies have shown a diversity of insects interacting with ferns, although the evolutionary and ecological drivers of these interactions are still to be untangled. To fill these gaps, we compiled more than 100 yr of global data on insect-fern interactions from the literature comprising 374 fern and 649 insect species. With this database we assessed how fern trophic specialization, phylogenetic relationships and climate have shaped their interactions with insects. Our findings showed that interactions between ferns and insects can be explained by the phylogenetic relations among them. We observed that insect orders part of the Endopterygota clade tend to interact with similar fern species, which might be a result of the inheritance of Endopterygota ancestors probably due to phylogenetic niche conservationism. Under an ecological context, fern specialization increased with temperature, precipitation, and climatic stability. Our results show that climate might be one of the main factors explaining the spatial variation of insect-fern interactions, postulate also supported by the observed phylogenetic clustering of the studied ferns species. Our study highlights the intricate and multifaceted nature of insect-fern interactions, where evolutionary history and ecological factors converge to shape these relationships.

Managing the Global Wetland Methane-Climate Feedback: A Review of Potential Options.

Methane emissions by global wetlands are anticipated to increase due to climate warming. The increase in methane represents a sizable emissions source (32-68 Tg CH4 year-1 greater in 2099 than 2010, for RCP2.6-4.5) that threatens long-term climate stability and poses a significant positive feedback that magnifies climate warming. However, management of this feedback, which is ultimately driven by human-caused warming and thus "indirectly" anthropogenic, has been largely unexplored. Here, we review the known range of options for direct management of rising wetland methane emissions, outline contexts for their application, and explore a global scale thought experiment to gauge their potential impact. Among potential management options for methane emissions from wetlands, substrate amendments, particularly sulfate, are the most well studied, although the majority have only been tested in laboratory settings and without considering potential environmental externalities. Using published models, we find that the bulk (64%-80%) of additional wetland methane will arise from hotspots making up only about 8% of global wetland extent, primarily occurring in the tropics and subtropics. If applied to these hotspots, sulfate might suppress 10%-21% of the total additional wetland methane emissions, but this treatment comes with considerable negative consequences for the environment. This thought experiment leverages results from experimental simulations of sulfate from acid rain, as there is essentially no research on the use of sulfate for intentional suppression of additional wetland methane emissions. Given the magnitude of the potential climate forcing feedback of methane from wetlands, it is critical to explore management options and their impacts to ensure that decisions made to directly manage-or not manage-this process be made with the best available science.

Exploring climate stabilisation at different global warming levels in ACCESS-ESM-1.5

Abstract. Under the Paris Agreement, signatory nations aim to keep global warming well below 2 °C above pre-industrial levels and preferably below 1.5 °C. This implicitly requires achieving net-zero or net-negative greenhouse gas emissions to ensure long-term global temperature stabilisation or reduction. Despite this requirement, there have been few analyses of stabilised climates, and there is a lack of model experiments to address our need for understanding the implications of the Paris Agreement. Here, we describe a new set of experiments using the Australian Community Climate and Earth System Simulator Earth system model (ACCESS-ESM-1.5) that enables the analysis of climate evolution under net-zero emissions, and we present initial results. Seven 1000-year-long simulations were run with global temperatures stabilising at levels in line with the Paris Agreement and at a range of higher global warming levels (GWLs). We provide an overview of the experimental design and use these simulations to demonstrate the consequences of delayed attainment of global net-zero carbon dioxide emissions. We show that there are substantial differences between transient and stabilising climate states and differences in stabilisation between GWLs. As the climate stabilises under net-zero emissions, we identify significant and robust changes in temperature and precipitation patterns including continued Southern Ocean warming and changes in regional precipitation trends. Changes under net-zero emissions differ greatly between regions, including contrasting trajectories of sea ice extent between the Arctic and Antarctic. We also examine the El Niño–Southern Oscillation (ENSO) and find evidence of reduced amplitude and frequency of ENSO events under climate stabilisation relative to projections under transient warming. An analysis at specific GWLs shows that significant regional changes continue for centuries after emission cessation and that these changes are stronger at higher GWLs. Our findings suggest substantial long-term climate changes are possible even under net-zero emission pathways. These simulations are available for use in the community and will hopefully motivate further experiments and analyses based on other Earth system models.

Sustainable biomass derived natural surfactant of soybean seeds in fly ash industrial waste utilization for carbon storage: Evaluation of environmental impact

The rising carbon emissions challenge global environmental sustainability and climate stability. This study aims to advance climate change mitigation by integrating fly ash and natural surfactant into CO2 sequestration strategies. Fly ash, a by-product of industrial processes, presents an opportunity for innovative reuse. By combining fly ash with a natural surfactant extracted from soybean seeds, both industrial waste management and greenhouse gas reduction can be addressed. The surfactant was characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, surface tension, and electrical conductivity measurements, confirming saponin presence with a critical micelle concentration of 0.3 wt%. Pressure decay studies revealed that a (5 wt% fly ash + NS) demonstrated the highest CO2 absorption, supported by microscopic analysis. Further research on optimizing reaction conditions and kinetics of mineralization could enhance this method’s efficiency and scalability for broader application.

Integrating basic human values with forest ecosystem services: pathways to sustainable forest management.

The article explores the intricate relationship between basic human values and forest ecosystem services (FES). The study highlights the critical role that forests play in providing essential services for biodiversity, forest products, climate stabilization and human well-being, and emphasizes the need to understand and integrate human values into forest management and planning. Through a novel approach, this study explores how the concept of "forest" can elicit considerations of fundamental human values that diverge from conventional classifications and measurements of forest values. The study uses a comprehensive methodology, including surveys and content analysis, to uncover the hierarchical structure of human values associated with forests. This approach enables the identification of fundamental values that remain constant despite situational variations. The main results reveal a hierarchical structure of values, with Apollonian values being more prevalent than Dionysian ones. The study shows significant differences in the importance attributed to different FES, reflecting underlying value differences between residents. The study makes a novel contribution by systematically examining the links between human values and FES and proposing a profound and sustainable approach to forest management that takes into account the psychological dimensions of human-forest interactions. The study suggests that recognizing and incorporating the intrinsic human values into forest ecosystem service frameworks can improve sustainable forest management practices and ultimately foster a deeper connection between people and the forest environment.

Dominant influence of biomass combustion and cross-border transport on nitrogen-containing organic compound levels in the southeastern Tibetan Plateau

Abstract. The Tibetan Plateau (TP) is highly susceptible to climate change, and nitrogen-containing organic compounds (NOCs) in fine particulate matter (PM2.5) represent one of the largest uncertainties with respect to their impact on the climate in high-altitude areas. Previous studies have shown that NOCs play a vital role in the nitrogen budget of PM2.5. However, our understanding of the composition and sources of NOCs in PM2.5, particularly in the TP, is limited. Here, we aim to enhance our understanding of NOCs in the TP region by examining their identification, concentration levels, sources, and origins. We conducted field sampling at a regional background sampling site in Gaomeigu, in the southeastern margin of the TP from 11 March to 13 May 2017, followed by laboratory analysis of the NOCs collected on the filters. The daily mass concentrations of NOCs ranged from 714.4 to 3887.1 ng m−3, with an average of 2119.4 ± 875.0 ng m−3 during the campaign. This average concentration was approximately 40 % higher than that reported at a typical regional site in the North China Plain (NCP), highlighting a more significant presence of NOCs in the Tibetan area. Biomass burning and secondary sources were identified as the major contributors to total NOCs. This was further substantiated by a regional air quality model, which indicated that over 80 % of the aerosol in the southeast of the TP originated from neighboring countries. This study improves our understanding of NOCs' contribution to PM2.5 in the TP and their potential impacts on climate stability in high-altitude areas.

AUTONOMOUS MONITORING ROBOT SYSTEM THAT MEASURES AIR POLLUTION

Air pollution poses a significant threat to human health, ecosystems, and climate stability, necessitating effective monitoring and control measures. Traditional air quality monitoring stations, while accurate, are static, expensive, and limited in coverage. The Autonomous Monitoring Robot System (AMRS) provides a dynamic solution, offering real-time air quality monitoring through mobile robotic platforms. Equipped with advanced sensors, these robots can measure various pollutants, such as particulate matter (PM), nitrogen dioxide (NO2), carbon monoxide (CO), and volatile organic compounds (VOCs), across large and complex areas. By employing AI-based navigation and mapping technologies, AMRS can autonomously traverse urban and industrial environments, collecting high-resolution pollution data and creating real-time air quality maps. This approach allows for better spatial coverage, cost-efficiency, and access to hard-to-reach locations compared to traditional methods. The system can be deployed in diverse use cases, including urban air quality monitoring, industrial pollution control, and disaster management. While challenges such as battery life, sensor calibration, and data processing remain, AMRS represents a promising technological advancement in environmental monitoring and pollution control.

History of Ambo Ambaa Lafaa of Western Shewa Zone of Oromia Regional State: The Heartland of Hero and Heroism

History is indispensable to understanding ourselves and the world around us. This study attempts to construct the history of Ambo Ambaa lafaa of western shewa zone of Oromia regional state. Its foundation, gradual change, economic activity, politico-administration and religion in different leaders. Further the study recognizes the problem which affects the development of Ambo town. In this study, the researcher utilized primary, secondary and pamphlet sources as well as oral information through interview in order to gather the data. The collected data was organized and analyzed using qualitative research methods. The study is based on historical and Ethnographic approach. The historical foundation of Ambo was not directly concern for the cause of military garrisons like many other Ethiopia Towns, its growth and internal character came to be closely connected with the mineral water, God Bridge and commercial activities. Ambo is town found in west shewa zone of oromia regional state. Ambo was known by pride of their nation in different era of various ruler of Ethiopia. They struggles for their right and know their responsibility simultaneously. Ambo known by patriots, hero and brave those who stand for the freedom of country in any controversy and pleasure time. The society of town needs peace, stability, truth, justice, equality, brotherly hood and fraternity with diverse nation and nationalities in the empire, because Oromo are founders of gada system that did for equality of human beings. Ambo town was established in late of 19<sup>th</sup> century. At the beginning the spatial size of Ambo town is small, it is around 1320 hectares and became expand to 8578 hectares after it makes gradual expansion to the neighboring farm land. As the result Ambo is very comfortable for different investment activities because of comfortable climate condition and stability (safety) in area, there is also different attraction site including Wanchi lake, Dandi Lake (it had number eight shape/symbol), Guder fall, obse fall, old palace of emperor Haile sillase and other different natural, cultural and ritual sites