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Near or far?
\"Near and far are important concepts to understand--who doesn't want to know if a shark is near or far? This colorful volume is an enjoyable exploration of this pair of opposites. It invites beginning readers to practice using these terms in relation to familiar and fun scenarios in the real world. They'll spot near and faraway elephants, sharks, birds, and boats in the lively photographs accompanying the achievable text.\"-- Provided by publisher.
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Hydrologic regulation of plant rooting depth
Plant rooting depth affects ecosystem resilience to environmental stress such as drought. Deep roots connect deep soil/groundwater to the atmosphere, thus influencing the hydrologic cycle and climate. Deep roots enhance bedrock weathering, thus regulating the long-term carbon cycle. However, we know little about how deep roots go and why. Here, we present a global synthesis of 2,200 root observations of >1,000 species along biotic (life form, genus) and abiotic (precipitation, soil, drainage) gradients. Results reveal strong sensitivities of rooting depth to local soil water profiles determined by precipitation infiltration depth from the top (reflecting climate and soil), and groundwater table depth from below (reflecting topography-driven land drainage). In well-drained uplands, rooting depth follows infiltration depth; in waterlogged lowlands, roots stay shallow, avoiding oxygen stress below the water table; in between, high productivity and drought can send roots many meters down to the groundwater capillary fringe. This framework explains the contrasting rooting depths observed under the same climate for the same species but at distinct topographic positions. We assess the global significance of these hydrologic mechanisms by estimating root water-uptake depths using an inverse model, based on observed productivity and atmosphere, at 30″ (∼1-km) global grids to capture the topography critical to soil hydrology. The resulting patterns of plant rooting depth bear a strong topographic and hydrologic signature at landscape to global scales. They underscore a fundamental plant–water feedback pathway that may be critical to understanding plant-mediated global change.
Journal Article
El Niño's warmth devastating reefs worldwide
Recent aerial surveys of Australia's Great Barrier Reef find massive coral bleaching. Even as recently as early March, Australian coral reef scientists still hoped that the legendary Great Barrier Reef (GBR) would get off lightly in the current El Niño, the climate phenomenon that brings unusually warm water to the equatorial Pacific, stressing and often killing corals. No such luck. On 20 March, the GBR Marine Park Authority in Townsville, Australia, reported that divers were finding extensive coral bleaching—the loss of symbiotic algae—in remote northern areas of the reef. Many sections were already dead. Subsequent flyover surveys have confirmed an unfolding disaster, with only four of 520 reefs appearing unscathed. The GBR joins a lengthening list of reefs bleached because of the El Niño that started in late 2014. It is now the longest bleaching event ever, and many more corals worldwide will likely die.
Journal Article
Cash incentives for papers go global
China's rewards are richest, but many nations offer bonuses for publishing in top journals China is well known for the generous bonuses it pays scientists who land a peer-review publication in a top journal like Science or Cell. But scientists in many countries are reaping similar bounties. Awards are primarily cash; some are as small as the$10 that Oakwood University in Huntsville, Alabama, bestows on authors when their papers are cited in the literature. At the other end of the scale, scientists at Chinese institutions stand to make a small fortune if a paper they author appears in journals with high citation impacts. A recent analysis posted to arXiv showed that, on average, Chinese universities offer first authors more than $ 43,000 for publishing a paper in Science or Nature, with the top reward for such a paper receiving a knee-wobbling $165,000.
Journal Article
Dengue researcher faces charges in vaccine fiasco
Rose Capeding could face years in prison for role in tests. Rose Capeding, former head of the dengue department of the Research Institute for Tropical Medicine in Manila, has been indicted in a series of criminal cases over the failed introduction in the Philippines of Dengvaxia, a vaccine against dengue that was yanked from the market in 2017 because of safety issues. In February, a panel of prosecutors concluded that there is probable cause to indict Capeding and 19 others for \"reckless imprudence resulting [in] homicide,\" because of their role in the vaccine's approval and rollout. If convicted of accusations leveled at her by the national Department of Justice, Capeding could face up to 48 years in prison. Many scientists have come to her defense.
Journal Article
Hydrological niche segregation defines forest structure and drought tolerance strategies in a seasonal Amazon forest
1. The relationship between rooting depth and above-ground hydraulic traits can potentially define drought resistance strategies that are important in determining species distribution and coexistence in seasonal tropical forests, and understanding this is important for predicting the effects of future climate change in these ecosystems. 2. We assessed the rooting depth of 12 dominant tree species (representing c. 42% of the forest basal area) in a seasonal Amazon forest using the stable isotope ratios (δ¹⁸ and δ²H) of water collected from tree xylem and soils from a range of depths. We took advantage of a major ENSO-related drought in 2015/2016 that caused substantial evaporative isotope enrichment in the soil and revealed water mum dry season leaf water potential both in a normal year (2014; Ψnon-ENSO) and in an extreme drought year (2015; Ψnon-ENSO Furthermore, we measured xylem hydraulic traits that indicate water potential thresholds trees tolerate without risking hydraulic failure (P₅₀ and P₈₈). 3. We demonstrate that coexisting trees are largely segregated along a single hydrological niche axis defined by root depth differences, access to light and tolerance of low water potential. These differences in rooting depth were strongly related to tree size; diameter at breast height (DBH) explained 72% of the variation in the tree size; diameter at breast height (DBH) explained 72% of the variation in the δ¹⁸Oxylem Additionally, δ¹⁸Oxylem explained 49% of the variation in P₅₀ and 70% of P₈₈, with shallow-rooted species more tolerant of low water potentials, while δ¹⁸ of xylem water explained 47% and 77% of the variation of minimum Ψnon-ENSO and ΨENSO. 4. We propose a new formulation to estimate an effective functional rooting depth, i.e. the likely soil depth from which roots can sustain water uptake for physiological functions, using DBH as predictor of root depth at this site. Based on these estimates, we conclude that rooting depth varies systematically across the most abundant families, genera and species at the Tapajós forest, and that understorey species in particular are limited to shallow rooting depths. 5. Our results support the theory of hydrological niche segregation and its underlying trade-off related to drought resistance, which also affect the dominance structure of trees in this seasonal eastern Amazon forest. 6. Synthesis. Our results support the theory of hydrological niche segregation an demonstrate its underlying trade-off related to drought resistance (access to deep water vs. tolerance of very low water potentials). We found that the single hydrological axis defining water use traits was strongly related to tree size, and infer that periodic extreme droughts influence community composition and the dominance structure of trees in this seasonal eastern Amazon forest.
Journal Article
‘Science wars’ veteran has a new mission
Bruno Latour was a thorn in scientists' sides. Now, he wants to rebuild trust in their work. French sociologist Bruno Latour, 70, has long been a thorn in the side of science. But in the age of \"alternative facts,\" he's coming to its defense. Central to Latour's work is the notion that facts are constructed by communities of scientists, and that there is no distinction between the social and technical elements of science. In the 1990s, such relativist and \"social-constructivist\" views triggered a heated debate known as the \"science wars.\" In later writings, Latour acknowledged that the criticism of science had created a basis for antiscientific thinking and had paved the way for the denial of climate change. Latour, who retired last month from his official duties at Sciences Po, a university for the social sciences in Paris, spoke to Science about his goal of helping rebuild confidence in science.
Journal Article