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The elusive southern river otter (Lontra provocax; huillín in Spanish) is critically endangered in the Argentine portion of Tierra del Fuego, and low social awareness may be one of the major threats to its conservation. Our survey of local residents’ knowledge and valuation of the huillín showed that only 14% recognized photographs of the species, almost half did not know that it is endangered and most erroneously thought it was an introduced species. Greater knowledge about the huillín was related to higher respondent education levels. Younger and more knowledgeable residents valued the species more for ecological and relational reasons; its instrumental value was considered least important. More communication should be targeted at older people and groups not directly interacting with nature via informal education methods, including combining positive messages about the huillín and other native species with ongoing outreach efforts warning about biological invasions. Understanding perceptions and valuations of biodiversity can make conservation efforts more effective and inclusive.
Members of the Shewanella genus transfer electrons to metal and actinide electron acceptors such as hexavalent uranium, U(VI), via c-type cytochromes. The intracellular mechanism of electron transfer is well studied but the delivery of electrons to external electron acceptors less well so. MtrC, a decaheme c-type cytochrome located on the cell surface side of the outer membrane of many Shewanella species, and extending to the extracellular medium, transfers electrons to U(VI), both in vivo and in vitro when purified. However, it is unclear how the electron transfer between the terminal heme(s) of the protein and extracellular U(VI) occurs. In particular, the type of interaction between MtrC and U(VI), and the parameters controlling electron transfer remain to be elucidated. Here, we investigated the kinetics of U(VI) reduction by S. baltica MtrC in solution for U(VI) complexed with one of five ligands: carbonate, hydroxyl, citrate, nitrilotriacetic acid (NTA) or ethylenediaminetetraacetic acid (EDTA). We observed two initial reaction rates, one more rapid for U-citrate, U-NTA and U-EDTA, and another slower for U-carbonate and U-hydroxo. By combining Nuclear Magnetic Resonance spectroscopy and M4-edge High Resolution X-ray Absorption Near Edge Structure spectroscopy, we attributed these differences to the type of interaction between the U-ligand complex and MtrC, i.e., probably electrostatic interaction with the ligand of U-EDTA, hydrogen bonding to the ligand of U-citrate and U-NTA, and covalent bonding with U-carbonate and U-hydroxo. We also demonstrate the persistence of U(V) in the U-carbonate system when interacting with MtrC. Overall, we showed that the mechanism of electron transfer depended on the chemistry of the soluble U(VI) complex serving as the substrate.
Intensifying storms and inter-annual El Niño events may increase psychological stress and worsen mental health. This study examines the relationship between flood exposure and long-term mental health symptoms among adolescents and young people in Peru, the world’s most affected country by El Niño. We analyzed community and self-reported survey data from the Young Lives Study to contrast mental health in 2016 among youth who lived in communities that experienced or did not experience flooding between 2013 and 2016. We pre-processed data on 1344 individuals in 93 communities, using optimal full matching on Mahalanobis distance with a propensity score caliper, and estimated relative risks to mental health scores in the general population of young people and among gender-stratified groups via quasi-Poisson regression. Exposure to floods did not yield conclusive differences in mental health scores in this sample. Further evidence is needed on mental health patterns over time, the influence of exposure severity, and the impact of disaster relief on symptomology in mounting an effective global health response.
In humid, continental Michigan, we identified pedogenic carbonate in a soil profile developed on glacial drift sediments, as rinds, rhizoliths, and filaments (at depths >50 cm). Given that the climate setting is unusual for pedogenic carbonate, we investigated its formation with environmental monitoring and isotope analyses of carbonate (δ13C, δ18O, Δ47, and 14C) and waters (δ18O and δ2H). We found covariation in δ13C and Δ47 amongst the carbonate types (rhizoliths, rinds, filaments, bulk soil, and detrital clasts), and 14C ages of rinds that predate plausible formation ages. The δ13C and Δ47 values of the bulk carbonate and some of the pedogenic morphologies are not fully compatible with pedogenic formation in the modern environment. The δ18O data from precipitation and river waters and from carbonates are not uniquely identifying; they are compatible with the soil carbonate being pedogenic, detrital, or a mix. We conclude that the soil carbonate is likely a physical mix of pedogenic and detrital carbonate. Pedogenic carbonate is forming in this humid setting, likely because seasonal cycles in soil respiration and temperature cause cycles of dissolution and re-precipitation of detrital and pedogenic carbonate. The pedogenic carbonate may be a transient feature as carbonate-rich till undergoes post-glacial chemical weathering.
Agricultural intensification has led to significant species losses and has been associated with a decline in ecosystem services provided by insects. In Asia, particularly in Lao PDR (Southeast Asia), biodiversity-friendly agricultural practices such as the production of organic crops have been promoted to address these challenges, although intensification has continued. In this study, we examined beetle community composition in three organic farms (using, for example, manure and compost and not employing synthetic fertilizers and pesticides) and three conventional farms (using, for example, synthetic fertilizers and insecticides) in Vientiane (Lao PDR). Our results indicate that total beetle abundance was similar between farm types, while species richness was greater, predators were over 18 times more abundant and insect pests were 9 times less abundant in organic compared to conventional farms. These findings can inform government organic farming policy in Lao PDR and the promotion of sustainable agriculture in Southeast Asia generally.
In rural China, male offspring are traditionally regarded as the primary heirs of household assets, particularly land. This study examines the impact of offspring gender composition on long-term agricultural investment behavior, using commercial organic fertilizer application as an example of a strategic long-term investment in farmland. Based on cross-sectional data from 4090 rice farming households across 10 cities (counties) in Hubei province, collected between 2021 and 2023, this analysis identifies three key findings. First, the absence of male offspring significantly reduces long-term agricultural investments, a result that remains robust even when addressing potential endogeneity biases using instrumental variable techniques. Second, households without male heirs exhibit stronger present-oriented preferences and diminished social capital, which further hinder long-term agricultural investments. Third, the negative impact of not having male offspring is more pronounced when the current agricultural decision-maker is male and when land marketization is underdeveloped. These findings underscore the complex interplay between gender norms and agricultural behavior, revealing significant socioeconomic implications of inheritance practices. The study provides insights into addressing these challenges by emphasizing the importance of promoting gender equality and advancing land marketization to enhance equitable land use and support long-term agricultural investment.
A continental-type glacial flood termed the Suwałki megafloods took place in NE Poland during the last glaciation and significantly transformed the proglacial area. This study aims, for the first time, to establish the chronology of this flood. Twenty-two sediment samples from two meltwater spillways were dated by optically stimulated luminescence. Sixteen ages from the flood megadunes are between 83 ± 11 ka and 16.9 ± 0.9 ka, whereas six ages from the outwash tracks range from 71.5 ± 9.9 ka to 20.3 ± 2.5 ka. Three dates from the uppermost part of the megadune sedimentary successions are 16.9 ± 0.9 ka, 17.9 ± 1.9 ka, and 18.8 ± 1.3 ka, and they may mark the likely true age of the Suwałki megafloods. We found no consistent relationships between the sedimentary structures and bleaching characteristics suggesting that the two are largely independent, contrary to what is typically assumed for fluvial deposits. Similarly, the transport distance from the ice margin did not exert a consistent influence on the sediment bleaching characteristics. A new hypothesis considers the stage of flooding to have a relevant impact on sediment bleaching: sediment deposited during the flood waning is well bleached and has a high potential for constraining the flood age.
There is growing interest in producing more beef from cattle raised in pasture-based systems, rather than grain-finishing feedlot systems in the USA. Given the availability of high-quality forage, pastureland, and markets in the northeastern USA, an expansion of beef production in the region contributes to a gradual shift toward grass-based finishing systems. However, the existing capacity of slaughter and processing facilities in the region is not sufficient to meet the service demand as grass-finished beef cattle production expands. This article examines slaughter and processing bottleneck problems under three scenarios of grass-finished beef production expansion. Through modeling the optimal utilization and expansion of currently existing plant capacity in the region, this study identifies capacity expansion solutions to overcome the emerging bottleneck problems. The plant utilization and expansion problem is formulated as an optimization model with the objective of minimizing total costs associated with cattle assembly, slaughter, processing, and distribution. Our results suggest that slaughter bottlenecks in New York State coincide with underutilized slaughter capacity in New England. Reducing plant numbers while increasing plant utilization rates or expanding the capacity of the remaining plants, would likely lead to greater cost savings.
The Lorne Plateau lava succession of the north-west Grampian Highlands of Scotland is an early component of post-collisional Late Silurian to Early Devonian magmatism in the Orthotectonic Caledonides emplaced in two phases between the Late Silurian (425.0±0.7 Ma U-Pb zircon) and the Siluro-Devonian boundary at ∼419 Ma. Palaeomagnetic study comprising thermal demagnetization and component analysis embracing the time frame of the preserved succession yields a coherent mean direction of magnetization from 58 sites (D/I = 43.7/−47.4°, α95 = 4.0°). A palaeomagnetic fold test is significantly positive with sills intruding unlithified sediment on the island of Kerrera confirming primary remanence. The ∼600 m thick succession has uniform normal polarity throughout permitting correlation with the beginning of a normal polarity chron extending from ∼426 to 403 Ma. The pole position at 2.7°N, 317.3°E (dp/dm = 3.8/5.8°) predicts a palaeolatitude of 26°S and corresponds precisely with remanence in contemporaneous rocks from the Midland Valley of Scotland. Regional palaeofield directions are evaluated in the context of transpressional moulding of the Acadian Orogeny on the Great Glen Fault system (~416−380 Ma).
Paleoproterozoic granitoids of the lesser Himalayan belt are keys to understanding the evolution of the northern Indian continental margin and its position in the Columbia supercontinent assembly. We present whole-rock chemistry and zircon U-Pb geochronological data for Gwaldam Biotite Granite (GBGr) from the Baijnath Klippe (BK) in Kumaun Himalaya to elucidate their petrogenesis and geodynamic implications. Granites are characterized by ferroan, weakly peraluminous nature with high SiO2 and K2O contents, enrichment in LILE (Rb, Th, K and Pb), and depletion in Ba, Nb, P, Hf and Ti. Granites show enrichment in light rare earth element relative to heavy rare earth elements and pronounced negative Eu anomalies. Such chemistry suggests typical A-type granite with high Y/Nb >2 values that characterize it as A2-type granite. Zircon U-Pb ages for the granite yield upper intercept at 1900 ± 3 Ma (core) and 1854 ± 2 Ma (rim). Integrating the chemical and geochronological data, we propose a two-stage evolution model for the area. In the GBGr, the ∼1900 Ma date of zircon core is likely the date of crystallization of the melts presumably formed during the first extensional stage at uppermost mantle – lower crust levels caused by slab break-off/rollback, which followed a post-collisional setting. The second incipient rifting stage produced melt that entrained the zircon cores (∼1900 Ma) during its ascendance and crystallized as the GBGr at ∼1854 Ma when the zircon rims crystallized. It is further proposed that the Paleoproterozoic Northern Indian continental margin later underwent at least two crustal extensions during the Columbia supercontinent agglomeration.
A rock cairn, with two matchbooks buried beneath, was found on the summit of the highest hill on Thomas Island, Bunger Hills, East Antarctica. The matchbooks are most likely from United States World War II-era ration packs, which were distributed to various military and civilian expeditions from the mid-1940s into the 1950s. Bunger Hills was first visited by United States Navy ‘Operation Highjump’ in February 1947, when a seaplane most likely landed on a marine inlet, rather than a lake as reported previously. Thomas Island was first visited by United States Navy ‘Operation Windmill’ in January 1948, when a survey point was established, and it is probably this location that is marked by the rock cairn. The matchbooks were replaced beneath the cairn and the rocks replaced. Just over 76 years had elapsed between burial of the matchbooks, construction of the cairn and their rediscovery.
Obruchevodid petalodonts are rare small chondrichthyans known from nearly complete to partial skeletons from the Upper Mississippian (Serpukhovian) Bear Gulch Limestone of central Montana and isolated teeth from the Upper Mississippian Bangor Limestone of northern Alabama. New records of obruchevodid petalodonts are presented here from the Middle Mississippian (Viséan) Joppa Member of the Ste. Genevieve Formation at Mammoth Cave National Park, Kentucky. Obruchevodids are here represented by multiple teeth of a new taxon, Clavusodens mcginnisi n. gen. n. sp., and a single tooth referred to ?Netsepoye sp. Clavusodens mcginnisi n. gen. n. sp. is characterized by teeth with pointed mesiodistal and lingual margins and more robust chisel-like cusps on the anterolateral and distolateral teeth. The suggestion that obruchevodid petalodonts evolved to inhabit complex reef-like environments and other nearshore habitats with a feeding ecology analogous to extant triggerfish is explored and discussed.
Identifying feeding interactions in the fossil record remains a key challenge for paleoecologists. We report the rare occurrence of a conical, perforative bite mark in a cervical vertebra of an azhdarchid pterosaur, which we identified as a juvenile individual of Cryodrakon boreas Hone, Habib, and Therrien, 2019 from the Campanian Dinosaur Park Formation in Alberta, Canada. Based on comparative analysis of the dentition and ecomorphology of potential trace makers in the Dinosaur Park Formation, as well as the morphology of the trace, the most likely candidate is a crocodilian, although whether it was made as a result of scavenging or predatory behavior is unknown. Feeding interactions involving pterosaurs are rare globally, whereas crocodilian bite marks are not uncommon in Cretaceous terrestrial ecosystems. Given the opportunistic feeding style and known range of food items for both extant and extinct crocodilians, pterosaurs can be counted as a rare, but not surprising, component of at least some Cretaceous crocodilian diets.
Prediction of dynamic environmental variables in unmonitored sites remains a long-standing challenge for water resources science. The majority of the world’s freshwater resources have inadequate monitoring of critical environmental variables needed for management. Yet, the need to have widespread predictions of hydrological variables such as river flow and water quality has become increasingly urgent due to climate and land use change over the past decades, and their associated impacts on water resources. Modern machine learning methods increasingly outperform their process-based and empirical model counterparts for hydrologic time series prediction with their ability to extract information from large, diverse data sets. We review relevant state-of-the art applications of machine learning for streamflow, water quality, and other water resources prediction and discuss opportunities to improve the use of machine learning with emerging methods for incorporating watershed characteristics and process knowledge into classical, deep learning, and transfer learning methodologies. The analysis here suggests most prior efforts have been focused on deep learning frameworks built on many sites for predictions at daily time scales in the United States, but that comparisons between different classes of machine learning methods are few and inadequate. We identify several open questions for time series predictions in unmonitored sites that include incorporating dynamic inputs and site characteristics, mechanistic understanding and spatial context, and explainable AI techniques in modern machine learning frameworks.
Proper identification of behavioral patterns is an important prerequisite for the identification of any trace fossil and even more so for its interpretation. For the last 70 yr, the continually advancing state of ichnological knowledge has led to a gradual recognition of recurrent patterns of organismal behavior documented in the fossil record, which in turn gave rise to the ethological categories. “Mortichnia” was proposed for traces created during a death struggle of the tracemaker but has been reported only in a few cases. Fish mortichnia so far have only been reported in one specimen recovered from the Upper Jurassic Plattenkalk of Nusplingen (SW Germany). The category mortichnia is refined herein, but remains ambiguous. Eight newly discovered unique specimens of mortichnia from Upper Cretaceous marine sediments in central Lebanon (Haqil, En Nammoura) are preserved together with their tracemakers and described herein. In addition, 14 further incomplete specimens were collected where no tracemakers are present. However, morphology and close provenance allow them to be assigned to the same ichnotaxon.
The Lebanese mortichnia originate from fish that were subjected to significant environmental or individual stress leading to their deaths. During death convulsions, their bodies created sedimentary structures with a specific recurring morphology. The ichnogenus Pinnichnus n. igen. with ichnospecies P. haqilensis and P. emmae n. ispp. is proposed for these specimens.
The Ediacaran/Cambrian transition (ECT; ~575–500 Ma) captures the early diversification of animals, including the oldest crown-group taxa of most major animal phyla alive today. Key to understanding the drivers underneath the ECT macroevolutionary patterns are the interactions of animals with one another and their environment, and how these interactions scale up to global diversity patterns. Understanding the ecology of ECT organisms is enabled by the abundance of Lagerstätten over this time period, with a relatively large proportion of soft-bodied organisms preserved, often within the communities in which they lived. Here, we review our understanding of organismal, community, and macroecology of the ECT, and how these different scales of ecological analyses relate to the macroevolutionary diversification patterns we see over this 75 Myr time period. Across all ecological scales, we find clear trends, starting with stochastic ecosystem dynamics dominated by generalist taxa in the first Ediacaran communities, to more structured, niche-driven specialist dynamics by Cambrian Epoch 2. These trends are reflected in organism functional morphology, the complexity and strength of organisms’ interactions within their communities, and large-scale metacommunity, biogeographic, and biodiversity patterns. Yet there is often a time delay between the origination of a new type of ecological interaction and when it is observed to impact the ecosystem as a whole. As such, while many modern ecological innovations were in place by the end of the Cambrian, the knock-on effects and complexity of these interactions continued to build up throughout the Phanerozoic, leading to the complex biosphere we have today.
Machine learning models have been used extensively in hydrology, but issues persist with regard to their transparency, and there is currently no identifiable best practice for forcing variables in streamflow or flood modeling. In this paper, using data from the Centre for Ecology & Hydrology’s National River Flow Archive and from the European Centre for Medium-Range Weather Forecasts, we present a study that focuses on the input variable set for a neural network streamflow model to demonstrate how certain variables can be internalized, leading to a compressed feature set. By highlighting this capability to learn effectively using proxy variables, we demonstrate a more transferable framework that minimizes sensing requirements and that enables a route toward generalizing models.
We examine a common pool resource (CPR) where appropriations deteriorate the quality of the resource and, thus, its impact on the exploitation of the CPR. We focus on two settings: (i) firms use the CPR without abatement efforts, and (ii) abatement is allowed. We provide comparisons between these two settings and identify socially optimal appropriation levels. We find that (i) higher quality of the CPR could induce firms to overuse the resource, and (ii) first-period appropriations with abatement decrease in the regeneration rate. However, abatement induces an overuse of the resource when the quality of the CPR improves.
With the green, circular, and low-carbon concept, eco-industrial parks are regarded as key drivers for maximizing environmental and economic benefits. Based on the panel data of 276 cities in China from 2007 to 2018, this paper regards the establishment of eco-industrial parks as a quasi-natural experiment, and employs the difference-in-differences method to test the impact of eco-industrial parks on urban haze pollution. We find that eco-industrial parks significantly reduce urban haze pollution and the conclusion holds with robustness tests. Heterogeneity analysis shows that the effect of eco-industrial parks on haze pollution is more pronounced in eastern and resource-based cities. Finally, mechanism analysis indicates that eco-industrial parks reduce urban haze pollution mainly by promoting technological innovation, upgrading industrial structure, and strengthening urban environmental regulations.