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Demographics of genetic admixture and expansion
No full textWe explore the dynamics of genetic admixture and expansion, as well as language assimilation, through mathematical-demographic modeling. Our primary goal is to address the population-genetics 'paradox' wherein autosomes and allosomes present markedly different, if not contradictory, pictures of past migrations. We demonstrate that this paradox may find a purely demographic explanation, as single-sex and two-sex reproduction models exhibit markedly distinct dynamics. We illustrate that the three processes-allosomal expansion, autosomal admixture, and language assimilation-occur at significantly different modes, potentially explaining the varied outcomes of these processes upon the completion of ethnogenetic transitions. Our research offers valuable insights into the intricate interplay between demography, genetics, and social organization, providing implications for historical scenarios and enhancing our understanding of the long-term consequences of migration and social cohesion
A new hope or phantom menace? Exploring climate emotions and public support for climate interventions across 30 countries
Get PDFEmotions are central to human experiences of climate change. Empirical research demonstrates their importance for climate perceptions and climate‐related behaviors. The intensifying severity of climate change prompts consideration of emerging, potentially controversial technologies. Alongside mitigation and adaptation, climate intervention proposes to remove carbon dioxide from ambient air (carbon dioxide removal, CDR) or reflect sunlight away from the Earth (solar radiation modification, SRM). Although such options arouse emotional reactions of diverse kinds, the intersection between climate emotions and climate intervention has received limited attention. This article employed a unique, global dataset with 30,284 participants across 30 countries (in 19 languages) to provide insights on 3 questions. We first leveraged the global dataset to map the incidence of fear, hope, anger, sadness, and worry across countries—the first time the climate emotions of adults are investigated on this scale. We also identified significant differences in emotions by level of development, with those in advanced economies reporting weaker levels of climate emotions. Second, using multiple linear regression analyses, we explored the relationship between climate emotions and support for climate‐intervention technologies. We determined that the emotions of hope and worry seem to be the most consistently (positively) correlated. Third, we explored if reading about technology categories differentially affected climate emotions. Individuals randomly assigned to read about ecosystems‐based CDR were significantly more hopeful about climate change (those about SRM the least). Together, our results provide the first global‐level evidence of the relationship between discrete climate emotions and perceptions and support of climate interventions
Climate change threatens the sustainability of current timber harvesting practices across a latitudinal gradient in Siberia
Get PDFThe boreal forests of Eurasia form the largest contiguous terrestrial biome in the world, providing numerous ecosystem functions and services for human societies. Temperatures are increasing most rapidly in high northern latitudes, altering tree growth and competition dynamics, and modifying disturbance regimes. The effect of these cumulative changes on the ecosystem functions provided by boreal forests is difficult to predict. We used the process-based LANDIS-II forest landscape model to evaluate how climate change and timber harvesting will interact to alter the production of ecosystem functions and services in boreal forests on three study areas across a large latitudinal gradient (11°) in central Siberia. We found that the relative importance of wood harvesting as a disturbance type varied depending on latitude and its impact was always far less than that of fire. Moderate climate change increased the availability of wood for harvest in the northern landscape, but wood availability declined in the southern landscapes under any amount of climate change likely because of an increase in the frequency of fire that kept forests too young for harvest. Modest climate change (RCP6.0) increased productivity and the storage of carbon in all landscapes but severe climate change (RCP8.5) reduced both in the southernmost landscape. Harvesting as a specific driver of change in these boreal forests is likely to be relatively minor except as a forest fragmentation process. Our results provide compelling evidence that status quo forest management in these landscapes is likely not sustainable, suggesting that climate-smart forestry will be needed
A water sprinkler system for establishing fire protection lines and protecting large areas
Get PDFIn this section, contents regarding the Crown Water Spray Equipment for Forest Fires Protection (CWSEFFP) are presented, intended to expand the water screening capacity of sprinklers on houses adjacent to forests as presented in FireSmart and FireWise to more aggressively suppress wide-area fire spread and protect WUI communities from forest fires. Here, through indoor experiments to prevent the spread of surface fire flames, the sprinkling rate per unit area necessary to extinguish or prevent the spread of flames from pine coniferous forest surface fuels has been shown to be at least 100 mL.m2. The required minimum watering amount to prevent the spread of forest fires can vary significantly depending on various circumstances, such as forest fire intensity and weather conditions. In fact, the owner of a house that survived the 2017 Kansas wildfire said that he turned on the sprinklers before evacuating, and when he returned, his house and cows were alive. (https://weather.com/news/news/kansas-wildfire-home-spared)
Introduction to self-protection systems
Get PDFForest fires pose great threats not only to forests, but also to villages and facilities adjacent to forests and to houses within forests. Many reports warn that the occurrence and severity of forest fires will increase due to climate change, and many cases of forest fires supporting these warnings are appearing around the world. The occurrence of such forest fires not only affects areas that have not been invaded by humans, such as Alaska, the frozen soil regions of Siberia, and the Amazon, but also poses threats to many cities where people are living in areas near forests
Who pays more? Exploring cost disparities in medication abortion access across socio-demographic groups in Ghana
Get PDFBackground
Medication abortion (MA) may be accessed covertly in private pharmacies and clinics due to abortion-related stigma. Stigmatization may lead to information asymmetry, resulting in price discrimination. The existing literature on abortion in Ghana has primarily focused on factors associated with abortion stigma. However, the potential variations in MA cost have not been explored. Thus, we aim to explore the potential disparities in MA cost based on women’s socio-demographic status in Ghana.
Methods
We used data from a study that recruited women who accessed MA using mifepristone and misoprostol combination from selected private pharmacies and clinics in Ghana. The study employed a non-inferiority and prospective design, and women were recruited as they exited the selected facilities after obtaining the MA pills. Our final analysis included 929 pharmacy clients and 1,045 clinic clients. To understand the variability in MA cost, we initially conducted two decomposition analyses using the variance and Blinder-Oaxaca techniques, followed by linear regressions to identify the socio-demographic factors that predict MA cost.
Results
The average costs of MA were approximately US 24.00 for the clinic and pharmacy groups, respectively. Additionally, the cost varied between pharmacy and clinic groups and within each group. A greater segment of the variation among the clinic group stemmed from between facilities (78 percent), whereas, among the pharmacies, the bigger share came from within facilities (57 percent). Regression results further indicate that the cost of MA increased among women with higher education, those who have not been in a union with a partner and those who accessed MA in clinics.
Conclusions
MA cost in Ghana is largely based on providers' discretion and at the facility's management level. Additionally, the cost differs by women’s socio-demographic attributes. To reduce the disparities in MA costs, developing guidelines to address the health system challenges regarding MA provision and access is important. Educational programs on MA access, provision and legal framework could also reduce abortion-related stigma and cost variations
Machine learning-based rainfall-induced landslide susceptibility model and short-term early warning assessment in South Korea
Get PDFThe extreme rainfall events associated with climate change trigger landslides. Approximately 60% of South Korea comprises mountainous terrain, with steep slopes rendering it particularly prone to landslides. Despite the implementation of early warning systems by the Korea Forest Service (KFS), landslide damage remains substantial, with approximately 2345 hectares affected over the past 5 years, resulting in severe human and economic costs. The current 24-h early warning system, based on Tier 3 administrative division (Town), faces challenges in accurately identifying high-susceptibility landslide areas. Thus, a daily landslide susceptibility model that integrates landslide-associated conditioning factors with meteorological, topographic, and environmental data was designed to assess landslide susceptibility with a spatial resolution of 100 m. Using AutoML, we identified Random Forest as the optimal model for predicting landslide susceptibility. Training the model with landslide data from 2016 to 2022 resulted in an accuracy of 0.93, AUC of 0.98, and F- 1 score of 0.98. A kappa value of 0.85 indicated the effective classification of past landslides using testing data. Location-based validation using 2023 occurrences revealed highly susceptible classifications for 88% of 43 landslides, while spatial scale-based hazard assessment using observed data indicated high hazard for 96% of 607 landslides in Tiers 3 and 4 (Township). Weather forecasting was also found to affect accuracy, with 76% accuracy for forecasts made at 5:00 PM and 41% for forecasts made at 8:00 AM. It was confirmed that further calibration of forecasting data can enhance the performance of the susceptibility model. The designed process thus enhances landslide prevention and preparedness on both local and regional scales, offering a crucial tool for mitigating the impact of landslides in South Korea
Soil secrets and tree tales: An in-depth comparison of carbon storage in mixed and pure stands of pine and birch
Get PDFWith climate change intensifying droughts, pest outbreaks and fire risks, forest management practices are increasingly focused on stabilizing soil carbon (C) stocks, which are essential for long-term ecosystem productivity and climate change mitigation. Planting more species-rich forests has been proposed as a potential solution, but the impact of species selection and planting density on carbon stocks remains largely unknown, particularly in mixed-species plantations, where local water availability plays a key role. In this study, our objective was to examine the effects of tree diversity, water availability, and tree density on carbon stocks and fluxes. Using a 10-year-old tree diversity experiment, we investigated how pure monocultures of pine (Pinus pinaster) and birch (Betula pendula), as well as mixed pine-birch stands, influence carbon dynamics under contrasting water conditions and different tree densities. Our results indicated that tree species mixtures slightly increased total C stocks, primarily through enhanced soil C storage due to niche partitioning and greater root turnover. However, pine monocultures showed higher aboveground biomass productivity than birch monocultures and mixed stands, regardless of water availability. Overall, increased soil moisture enhanced both tree biomass and soil carbon stocks, especially in mixed stands, likely by alleviating drought stress for birch. In contrast, higher water availability accelerated litter decomposition, reducing C stocks in the litter layer. Tree density was a key driver of C storage, with denser stands of pine monocultures showing increased aboveground biomass but reduced understory C stocks. These findings highlight the context-dependent benefits of mixed stands: while species mixtures can enhance soil C storage and adaptability to drought, they may be inferior to pine monocultures in aboveground C storage, at least under the specific environmental conditions and temporal scale covered by our study. This study underscores the need for site-specific forest management strategies that balance productivity and C sequestration goals, offering guidance for climate change mitigation through alternative planting schemes adjusting tree density and species composition while maintaining ecosystem services
Feeding The Planet While Saving It: How New Foods Can Help!
No full textEating a lot of meat and dairy puts pressure on nature. It leads to deforestation, water pollution, and climate change. By 2050, there will be over 9 billion people on Earth. Without any change in the way we eat, environmental damage will only get worse. What if we could eat foods that taste like meat and milk, but without hurting the planet as much? Novel plant-based foods, like plant-based burgers or oat milk, are made to taste and feel like animal products while using less land, water, and producing fewer greenhouse gases. Traditional plant-based foods, like tofu, lentils, and chickpeas are also healthy, tasty, and better for the planet. If everyone gradually replaced half of their meat and dairy with plant-based options we could save forests, reduce emissions, and make food more affordable. Even small changes in diet can make a big difference for the planet—and our future
Temporal lag in nitrogen use efficiency and its implications for sustainable cropland management
No full textImproving nitrogen use efficiency (NUE) is crucial for sustainable agriculture. Despite recent advancements, China continues to face significant environmental risks due to nitrogen surplus. This study examines the spatiotemporal dynamics of cropland nitrogen use across 350 prefecture-level cities from 1980 to 2020. Results reveal a persistent “three highs and one low” pattern-high input, high output, high surplus, and low NUE. Although NUE increased from 35 % in 2003 to 49 % in 2020, the turning point occurred around 2005, coinciding with the national fertilizer reduction policy. Significant regional disparities remain, with low NUE in the Northwest and Qinghai-Tibet Plateau and high NUE in the Northeast and Sichuan Basin. A temporal lag between nitrogen input and NUE highlights the legacy effects of past nitrogen accumulation. Practices such as straw return and manure recycling in key regions have demonstrated benefits. Findings underscore the need for region-specific, resource-efficient nitrogen governance strategies to enhance long-term sustainability