Hasil untuk "Environmental sciences"

Douglas P. Murray

Zhiying Tang, Yihang Jia, Zhibing Lu et al.

Global climate change and intensified human activities drive rapid land use and land cover (LULC) changes, particularly in ecologically fragile regions like China's Southern Hilly Region (SHR), affecting ecosystem services (ESs) trade-offs/synergies. However, scale-dependent thresholds governing these relationships remain poorly quantified. We analyzed ESs dynamics (water yield, soil conservation, carbon storage, nutrient retention, habitat quality) across regional, watershed, and sub-watershed scales (1990–2020) using the InVEST model, sensitivity indices, and piecewise linear regression. ESs responses exhibited significant scale effects, with sub-watersheds showing the highest sensitivity to LULC changes and representing the most stable management unit. Particularly, we found that critical LULC thresholds regulate trade-offs/synergies: forest cover exceeding ∼70 % strongly enhanced synergies among multiple ESs, while cropland proportions between 30 and 65 % intensified trade-offs (e.g., between soil conservation and water yield). Impervious expansion consistently degraded ESs. Our results demonstrate that optimizing LULC patterns-prioritizing forest conservation (>70 % cover), limiting cropland (<65 %), and controlling urban sprawl-at the sub-watershed scale minimizes ESs trade-offs. This study establishes quantitative thresholds to guide targeted land-use planning and ecological restoration policies in hilly regions globally, supporting sustainable landscape governance.

Gabriel C Rau, José Bastías Espejo, R Ian Acworth et al.

Groundwater (GW) is the primary freshwater resource in many of the world’s drylands, sustaining millions of people and supporting agriculture and ecosystems where surface water is scarce or unreliable. Recharge in these regions is highly episodic and occurs mainly through ephemeral streams (i.e. focused recharge), yet the mechanisms that determine whether surface flows contribute to aquifer replenishment remain poorly constrained. A common assumption is that large floods dominate recharge, but evidence from long-term monitoring is limited and inconclusive. We combine a unique hydrogeological monitoring dataset from the arid zone (Fowlers Gap in western New South Wales, Australia) with numerical modelling of vadose zone processes to assess the controls on focused GW recharge. Our results show that even extreme floods that overtopped piezometers did not produce measurable recharge at the water table. In contrast, significant recharge occurred only during a temporal cluster of moderate flow events in 2022. Numerical simulations confirm that temporal flow clustering produces longer periods of ephemeral streamflow, which progressively wet the vadose zone, overcome evapotranspiration (ET)-driven moisture deficits, and increase relative hydraulic conductivity, enabling percolation to the water table. Isolated floods, by contrast, largely saturate only shallow sediments and water is subsequently lost to ET. By explicitly incorporating ET, our modelling provides a more realistic representation of dryland recharge dynamics and highlights the roles of antecedent conditions and vadose zone properties. These findings demonstrate that recharge is not governed by rainfall totals or intensity alone, but critically depends on the timing and sequence of storm events. The implications for climate change assessments and water management are substantial, as projected shifts toward more intense but less frequent rainfall may reduce opportunities for clustering and thereby limit GW replenishment. Process-based modelling and event-scale analyses are therefore essential for reliable recharge projections and sustainable GW management in drylands.

Tom Perreault, G. Bridge, J. Mccarthy

Mahdieh Danesh Yazdi, Yaguang Wei, Allison Sonntag et al.

Emma Asbridge, Claire Krause, Richard Lucas et al.

Tropical cyclones can significantly impact mangrove forests, with some recovering rapidly, whilst others may change permanently. Inconsistent approaches to quantifying these impacts limit the capacity to identify patterns of damage and recovery across landscapes and cyclone categories. Understanding these patterns is critical as the changing frequency and intensity of cyclones and compounding effects of climate change, particularly sea-level rise, threaten mangroves and their ecosystem services. Improvements in Earth observation data, particularly satellite-based sensors and datacube environments, have enhanced capacity to classify time-series data and advanced landscape monitoring. Using the Landsat archive within Digital Earth Australia to monitor annual changes in canopy cover and extent, this study aims to quantify and classify immediate and long-term impacts of category 3–5 cyclones for mangroves in Australia. Closed canopy mangrove forests experienced the greatest immediate impact (loss of canopy cover). Most immediate impacts were minor, implying limited immediate mortality. Impacts varied spatially, reflecting proximity to exposed coastlines, cyclone track and forest structure (height, density, condition and species). Recovery was evident across all cyclones, although some areas exhibited permanent damage. Understanding the impacts and characteristics of vulnerable and resilient forests is crucial for managers tasked with protecting mangroves and their services as the climate changes.

Mahdieh Danesh Yazdi, Heresh Amini, Yaguang Wei et al.

Irene Martinez-Morata, Benjamin C. Bostick, Otakuye Conroy-Ben et al.

AbstractThere is no safe level of exposure to inorganic arsenic or uranium, yet recent studies identified sociodemographic and regional inequalities in concentrations of these frequently detected contaminants in public water systems across the US. We analyze the county-level association between racial/ethnic composition and public water arsenic and uranium concentrations from 2000–2011 using geospatial models. We find that higher proportions of Hispanic/Latino and American Indian/Alaskan Native residents are associated with significantly higher arsenic and uranium concentrations. These associations differ in magnitude and direction across regions; higher proportions of non-Hispanic Black residents are associated with higher arsenic and uranium in regions where concentrations of these contaminants are high. The findings from this nationwide geospatial analysis identifying racial/ethnic inequalities in arsenic and uranium concentrations in public drinking water across the US can advance environmental justice initiatives by informing regulatory action and financial and technical support to protect communities of color.

Zamam Hassan, Fawad Z.A. Khan, Adel S. Aldosary et al.

The process of urban growth often results in the conversion of agricultural spaces, including orchards. In Pakistan, Multan - widely known as the city of Mangoes - has seen exponential urban growth in the past couple of decades, resulting in a huge loss of Mango orchards to urban settlements. This research focuses on investigating local farmers’ motivations for selling Mango orchards to urban colonies and their perceived implications of transforming mango orchards into residential areas in Multan, Pakistan. By surveying 100 participants, the study captures insights into urban expansion trends, primary motivations behind selling agricultural land, and the social, economic and environmental consequences of such conversions. Descriptive statistics and correlation analysis (heatmap) are used to dissect the farmers perceptions on the drivers and implications of Mango orchards' conversion to housing settlements in Multan, Pakistan. Notably, 96% of respondents highlighted that orchards nearer to urban centers were predominantly targeted for conversion. Furthermore, 57% believed less productive orchards were more frequently turned into urban developments. Our correlation analysis provided clarity on the economic dimensions. Participants who felt their orchard was not a profitable venture tended to see greater economic advantages from selling their orchards. Interestingly, individuals motivated by a desire to 'improve quality of life' generally observed an improvement in their living conditions post-sale. On the environmental spectrum, concerns such as potential future temperature rises were consistently associated with several selling motivations, indicating a broad awareness of environmental consequences. This comprehensive research highlight the interplay of economic, social, and environmental factors in orchard-to-housing conversions, presenting valuable knowledge for urban development strategists and decision-makers.

Yongfa Zhu, Chuncheng Chen, Changbin Zhang et al.

Udit Bhatia, Sarth Dubey, Tarik C. Gouhier et al.

Abstract Redressing global patterns of biodiversity loss requires quantitative frameworks that can predict ecosystem collapse and inform restoration strategies. By applying a network-based dynamical approach to synthetic and real-world mutualistic ecosystems, we show that biodiversity recovery following collapse is maximized when extirpated species are reintroduced based solely on their total number of connections in the original interaction network. More complex network-based strategies that prioritize the reintroduction of species that improve ‘higher order’ topological features such as compartmentalization do not provide meaningful performance improvements. These results suggest that it is possible to design nearly optimal restoration strategies that maximize biodiversity recovery for data-poor ecosystems in order to ensure the delivery of critical natural services that fuel economic development, food security, and human health around the globe.

Bo Chen, Wanru Chen, Miao Wang et al.

Abstract Metal–organic framework (MOF) and conjugated microporous polymers (CMP) are two groups of supramolecular structures with potential applications for artificial photosynthesis though their catalytic activities are yet to be improved. A MOF/CMP hybrid photocatalyst NU@FNBZ with markedly higher catalytic activity for CO2 reduction to CO is hereby reported. The hybrid catalyst benefits from the high CO2 adsorption capacity of NU and the high visible light response of FNBZ. Moreover, the covalent bonding facilitates the formation of type II heterojunction that allows electron transfer from FNBZ to NU, leading to improved catalytic activity in the electron rich NU and enhanced CO2 adsorption in the electron depleted FNBZ. This work manifests that multiple synergy effects can be achieved by rational design of hybrid supramolecular photocatalysts.

Simona Paolacci, Marcel A. K. Jansen, Vlastimil Stejskal et al.

Avian vectors, such as ducks, swans and geese, are important dispersers of plant propagules. Until recently, it was thought that small vegetative propagules were reliant on adherence to vectors and are unlikely to survive passage through the avian digestive tract. Here, we conclusively demonstrate that metabolically active angiosperms can survive passage through the digestive tract of a large-bodied waterbird. In addition, we show that extended periods of air exposure for up to 7 days does not inhibit the survival of plantlets embedded in faecal matter. Following air exposure, plantlets (n = 3000) were recovered from 75 faecal samples of mute swans, Cygnus olor, with the survival of 203 plantlets. The number of recovered and surviving plantlets did not significantly differ among durations of air exposure. For recovered plantlets, the long-term viability and clonal reproduction of two duckweed species, Lemna minor and L. gibba, were confirmed following greater than eight months of growth. These data further amplify the key role of waterbirds as vectors for aquatic plant dispersal and demonstrate the internal transport (i.e. endozoochory) of metabolically active plantlets. These data suggest dispersal of vegetative plant propagules by avian vectors is likely to be a common occurrence, underpinning connectivity, range expansion and invasions of some aquatic plants.

Alisin V.V.

The article considers the issues associated with the friction of radiation-hardened fluoroplastic on steel in a hydraulic fluid environment during the transition period at the beginning of movement. The friction coefficients are studied when starting from a standstill, at the beginning and in steady motion. Changes in the value of the friction coefficient and changes in the amplitude of oscillation of the friction moment are analyzed. Particular attention is paid to the influence of the restart of motion in a friction coupling. Quantitative relationships of tribological properties are established depending on the time of relative sliding of the samples. It is noted that the friction coefficients in different modes are differ a lot, however, the running-in process proceeds quickly and in the practice of operating hydraulic devices, the running-in process of fluoroplastic seals can be ignored

Romina D. Fernandez, Phillip J. Haubrock, Ross N. Cuthbert et al.

Abstract The high ecological impacts of many invasive alien trees have been well documented. However, to date, we lacked synthesis of their economic impacts, hampering management actions. Here, we summarize the cost records of invasive trees to (I) identify invasive trees with cost information and their geographic locations, (II) investigate the types of costs recorded and sectors impacted by invasive trees and (III) analyze the relationships between categories of uses of invasive trees and the invasion costs attributed to these uses. We found reliable cost records only for 72 invasive trees, accumulating a reported total cost of $19.2 billion between 1960 and 2020. Agriculture was the sector with the highest cost records due to invasive trees. Most costs were incurred as resource damages and losses ($3.5 billion). Close attention to the ornamental sector is important for reducing the economic impact of invasive trees, since most invasive trees with cost records were introduced for that use. Despite massive reported costs of invasive trees, there remain large knowledge gaps on most invasive trees, sectors, and geographic scales, indicating that the real cost is severely underestimated. This highlights the need for further concerted and widely-distributed research efforts regarding the economic impact of invasive trees.

Luca Mazzoni, Franco Capocasa, Maria Teresa Ariza Fernández

Consumer awareness regarding the significance of a well-balanced diet in preventing chronic diseases has increased significantly in recent years [...]

Amanda S. Latham, Amanda S. Latham, Julie A. Moreno et al.

Neuroinflammation is a universal characteristic of brain aging and neurological disorders, irrespective of the disease state. Glial inflammation mediates this signaling, through astrocyte and microglial polarization from neuroprotective to neurotoxic phenotypes. Glial reactivity results in the loss of homeostasis, as these cells no longer provide support to neurons, in addition to the production of chronically toxic pro-inflammatory mediators. These glial changes initiate an inflammatory brain state that injures the central nervous system (CNS) over time. As the brain ages, glia are altered, including increased glial cell numbers, morphological changes, and either a pre-disposition or inability to become reactive. These alterations induce age-related neuropathologies, ultimately leading to neuronal degradation and irreversible damage associated with disorders of the aged brain, including Alzheimer’s Disease (AD) and other related diseases. While the complex interactions of these glial cells and the brain are well studied, the role additional stressors, such as infectious agents, play on age-related neuropathology has not been fully elucidated. Both biological agents in the periphery, such as bacterial infections, or in the CNS, including viral infections like SARS-CoV-2, push glia into neuroinflammatory phenotypes that can exacerbate pathology within the aging brain. These biological agents release pattern associated molecular patterns (PAMPs) that bind to pattern recognition receptors (PRRs) on glial cells, beginning an inflammatory cascade. In this review, we will summarize the evidence that biological agents induce reactive glia, which worsens age-related neuropathology.

Audrey J. Gaskins, Lidia Mínguez-Alarcón, Trang VoPham et al.

Arin A. Balalian, Xinhua Liu, Julie B. Herbstman et al.

Bret Ericson, Howard Hu, Emily Nash et al.