nasa-gesdisc/es-publications-researchareas huggingface dataset:
Sub-lethal predatory shell damage does not affect physiology under high CO2 in the intertidal gastropod Tritia reticulata (2020)

Abstract Ocean acidification (OA) poses a major threat to marine animals, especially marine shelled invertebrates such as molluscs. Although many organisms are capable of compensating for the effects of OA, this can impose physiological costs and impact performance (e.g. through increased metabolism and decreased growth). Sublethal injuries on shells may provoke changes in energy allocation. Under acidified conditions, organisms would spend less energy on reproduction and somatic growth to repair the damage. Therefore, we analysed the physiological responses of the intertidal gastropod Tritia reticulata during shell regeneration under OA conditions. We simulated a sub-lethal predation event (a notch in the outer lip of the shell) and individuals were exposed to control (pH 8.08) and low pH scenarios (pH 7.88 and 7.65). After two months exposure, all individuals showed shell repair, with a full repair rate observed in 75% of individuals. Contrary to expectations, shell repair following sub-lethal damage and OA had no apparent impact on physiological state in terms of energy reserves (as measured by whole-animal Carbon/Nitrogen) or growth potential (as measured by whole-animal RNA:Protein and RNA:DNA ratios). As an intertidal organism, T. reticulata could be resilient to future global environmental change because of compensatory mechanisms that are inherent in intertidal animals, and may represent a robust species with which to study future scenarios of OA in temperate coastal ecosystems. However, unrestricted food availability during experiment could have played a role in the results and therefore food limitation should be considered in future studies regarding shell repair and metabolism under the effects of OA.

Research areas: Ecosystems, Atmospheric/Ocean Indicators
Changes in fish communities due to benthic habitat shifts under ocean acidification conditions (2020)

Ocean acidification will likely change the structure and function of coastal marine ecosystems over coming decades. Volcanic carbon dioxide seeps generate dissolved CO2 and pH gradients that provide realistic insights into the direction and magnitude of these changes. Here, we used fish and benthic community surveys to assess the spatio-temporal dynamics of fish community properties off CO2 seeps in Japan. Adding to previous evidence from ocean acidification ecosystem studies conducted elsewhere, our findings documented shifts from calcified to non-calcified habitats with reduced benthic complexity. In addition, we found that such habitat transition led to decreased diversity of associated fish and to selection of those fish species better adapted to simplified ecosystems dominated by algae. Our data suggest that near-future projected ocean acidification levels will oppose the ongoing range expansion of coral reef-associated fish due to global warming.

Research areas: Ecosystems, Atmospheric/Ocean Indicators
Bold and bright: shy and supple? The effect of habitat type on personality–cognition covariance in the Aegean wall lizard (Podarcis erhardii) (2022)

Animals exhibit considerable and consistent among-individual variation in cognitive abilities, even within a population. Recent studies have attempted to address this variation using insights from the field of animal personality. Generally, it is predicted that animals with faster personalities (bolder, explorative, and neophilic) should exhibit faster but less flexible learning. However, the empirical evidence for a link between cognitive style and personality is mixed. One possible reason for such conflicting results may be that personalitycognition covariance changes along ecological conditions, a hypothesis that has rarely been investigated so far. In this study, we tested the effect of habitat complexity on multiple aspects of animal personality and cognition, and how this influenced their relationship, in five populations of the Aegean wall lizard (Podarcis erhardii). Overall, lizards from both habitat types did not differ in average levels of personality or cognition, with the exception that lizards from more complex habitats performed better on a spatial learning task. Nevertheless, we found an intricate interplay between ecology, cognition, and personality, as behavioral associations were often habitat- but also year-dependent. In general, behavioral covariance was either independent of habitat, or found exclusively in the simple, open environments. Our results highlight that valuable insights may be gained by taking ecological variation into account while studying the link between personality and cognition.

Research areas: Ecosystems
Relationships between the distribution of wildlife and livestock diversity (2020)

AimWild biodiversity and agrobiodiversity are affected by challenges such as agricultural intensification. However, it is unknown whether or not both components of biodiversity respond similarly to environmental factors and to these challenges. Here, we examine the spatial relationships between the distributions of wild biodiversity and agrobiodiversity, to quantify how and where they covary across the geography.LocationMainland Spain, a European region that harbours high values of both wild and agro‑ biodiversity.MethodsWe used geographically weighted regression models to analyse the spatial variation in the relationships between the distribution of wild vertebrates and environmental and agrobiodiversity variables. We modelled the spatial gradients in species richness of native terrestrial vertebrates—that is, specific groups of amphibians, reptiles, birds and mammals—as a function of local livestock breed richness—that is, bovine, ovine, caprine, asinine, equine and porcine—climate variables and human footprint.ResultsWe found significant covariation between the distribution of native vertebrate species richness and climate, human footprint and livestock diversity. Overall, the association between species richness of the four wild terrestrial vertebrate groups and local livestock breed richness is positive across most of the studied area. However, local breed richness of cattle and sheep breed displays contrasting patterns, where cattle breeds associate positively to most wildlife vertebrates and sheep breeds show negative associations.Main conclusionWildlife diversity distributions are significantly associated with livestock agrobiodiversity. These spatial relationships are mediated by large‑scale environmental gradients. Since both, wildlife and livestock agrobiodiversity, tend to co‑occur spatially, future strategies for conservation in agricultural landscapes could benefit from integrated approaches.

Research areas: Ecosystems, Agriculture
The biophysical climate mitigation potential of boreal peatlands during (2020)

Peatlands and forests cover large areas of the boreal biome and are critical for global climate regulation. They also regulate regional climate through heat and water vapour exchange with the atmosphere. Understanding how land-atmosphere interactions in peatlands differ from forests may therefore be crucial for modelling boreal climate system dynamics and for assessing climate benefits of peatland conservation and restoration. To assess the biophysical impacts of peatlands and forests on peak growing season air temperature and humidity, we analysed surface energy fluxes and albedo from 35 peatlands and 37 evergreen needleleaf forests—the dominant boreal forest type—and simulated air temperature and vapour pressure deficit (VPD) over hypothetical homogeneous peatland and forest landscapes. We ran an evapotranspiration model using land surface parameters derived from energy flux observations and coupled an analytical solution for the surface energy balance to an atmospheric boundary layer (ABL) model. We found that peatlands, compared to forests, are characterized by higher growing season albedo, lower aerodynamic conductance, and higher surface conductance for an equivalent VPD. This combination of peatland surface properties results in a ∼20% decrease in afternoon ABL height, a cooling (from 1.7 to 2.5 °C) in afternoon air temperatures, and a decrease in afternoon VPD (from 0.4 to 0.7 kPa) for peatland landscapes compared to forest landscapes. These biophysical climate impacts of peatlands are most pronounced at lower latitudes (∼45°N) and decrease toward the northern limit of the boreal biome (∼70°N). Thus, boreal peatlands have the potential to mitigate the effect of regional climate warming during the growing season. The biophysical climate mitigation potential of peatlands needs to be accounted for when projecting the future climate of the boreal biome, when assessing the climate benefits of conserving pristine boreal peatlands, and when restoring peatlands that have experienced peatland drainage and mining.

Research areas: Ecosystems, Atmospheric/Ocean Indicators
Differences in insectivore bird diets in coffee agroecosystems driven by (2021)

Neotropical shade-grown coffee systems are renowned for their potential to conserve avian biodiversity. Yet, little is known about food resources consumed by insectivorous birds in these systems, the extent of resource competition between resident and migratory birds, or how management of shade trees might influence diet selection. We identified arthropods in stomach contents from obligate and generalist insectivorous birds captured in mist-nets at five coffee farms in Chiapas, Mexico between 20012003. Overall stomach contents from 938 individuals revealed dietary differences resulting from changes in seasons, years, and foraging guilds. Of four species sampled across all management systems, Yellow-green Vireo (
              Vireo flavoviridis
              ) prey differed depending on coffee shade management, consuming more ants in shaded monoculture than polyculture systems. Diets of obligate and generalist resident insectivores were 72% dissimilar with obligate insectivores consuming more Coleoptera and Araneae, and generalist insectivores consuming more Formicidae and other Hymenoptera. This suggests that obligate insectivores target more specialized prey whereas generalist insectivores rely on less favorable, chemically-defended prey found in clumped distributions. Our dataset provides important natural history data for many Nearctic-Neotropical migrants such as Tennessee Warbler (
              Leiothlypis peregrina; N = 163
              ), Nashville Warbler (
              Leiothlypis ruficapilla; N = 69
              ), and Swainsons Thrush (
              Catharus ustulatus; N = 68
              ) and tropical residents including Red-legged Honeycreepers (
              Cyanerpes cyaneus; N = 70
              ) and Rufous-capped Warblers (
              Basileuterus rufifrons; N = 56
              ). With declining arthropod populations worldwide, understanding the ecological interactions between obligate and generalist avian insectivores gives researchers the tools to evaluate community stability and inform conservation efforts.

Research areas: Ecosystems
Reproductive cycle of Donax punctatostriatus (Hanley, 1843)(Bivalvia: Donacidae) in a sandy beach of Sinaloa, Mexico (2018)

The reproductive cycle, stages of gonadal development, and minimum size of sexual maturity are described for a population of the clam Donax punctatostriatus Hanley, 1843 from a sandy beach in southern Sinaloa, Mexico. A total of 880 clams were collected from January 2009 to June 2010; 3.2% were sexually undifferentiated and 1.4% had the trematode parasite Postmonorchis sp, in the gonadal tissue. The total length of the clams ranged from 3.525.64 mm ( = 13.51, S.D. = 4.47 mm). The sexual proportion did not differ significantly from 1:1 (p > 0.05). The minimum size at sexual maturity (L50) was L50 = 12.03 mm. The gametogenic cycle comprise six stages of gonadal development (0-V). The population is reproductively active throughout the year and spawning is continuous, with three major peaks in April, July and September 2009. In March, when the water temperature was between 2123 C, most individuals were in stage I. This period is characterized by a rapid maturation of gametes. At the end of October and during November, when water temperature was warmer (2528 C), 50% of the individuals were in stage V (spent). Recruitment was more intense from July to October of 2009, when the highest temperatures of the year were recorded (2831 C). Photoperiod and the proportion of mature individuals of both sexes were significantly correlated (Pearson's correlation value = 0.62; p < 0.05). Since this clam is a potential resource for human consumption, the information here presented may contribute to a better management and use of their populations in the Mexican Pacific.

Research areas: Ecosystems
Spatio-temporal variability of the phytoplankton biomass in the Levantine basin between 2002 and 2015 using MODIS products (2017)

The Levantine basin in the Eastern Mediterranean Sea is subject to spatial and seasonal variations in primary production and physical-chemical properties both on a short and long-term basis. In this study, the monthly means of daily MODIS product images were averaged between 2002 and 2015, and used to characterize the phytoplankton blooms in different bioregions of the Levantine basin. The selected products were the sea surface temperature (SST), the chlorophyll-a concentration (Chl-a), the diffuse attenuation coefficient for downwelling irradiance at 490nm (Kd_490) and the colored dissolved organic matter index (CDOM_index). Our results showed that phytoplankton blooms were spatially and temporally variable. They occurred in late autumn at the Nile Delta, in early spring and late summer at the eastern coastline, and in spring at the northeastern coastline. The northern coastline and the open water had a common bloom occurring in winter. The Nile Delta was found to be the most productive area of the Levantine basin showing high Chl-a. Kd_490 and Chl-a present a parallel co-variation indicating a dominance of Case 1 waters in the Levantine basin. The CDOM_index shows a phase shift with the Chl-a fluctuation. A strong inverse correlation was observed between both Chl-a and CDOM_index with SST, connoting an indirect relation represented by a depression of CDOM in summer by photobleaching, and a suppression of the chlorophyll-a concentration due to water stratification, together with nutrient stress. An overestimation of the Chl-a values had been signaled by the use of the CDOM_index, suggesting a correction plan in a latter study.

Research areas: Ecosystems
Hot temperatures during the dry season reduce survival of a resident tropical bird (2018)

Understanding how climate change will shape species distributions in the future requires a functional understanding of the demographic responses of animals to their environment. For birds, most of our knowledge of how climate influences population vital rates stems from research in temperate environments, even though most of Earth's avian diversity is concentrated in the tropics. We evaluated effects of Southern Oscillation Index (SOI) and local temperature and rainfall at multiple temporal scales on sex-specific survival of a resident tropical bird, the rufous-and-white wren Thryophilus rufalbus, studied over 15 years in the dry forests of northwestern Costa Rica. We found that annual apparent survival of males was 8% higher than females, more variable over time, and responded more strongly to environmental variation than female survival, which did not vary strongly with SOI or local weather. For males, mean and maximum local temperatures were better predictors of survival than either rainfall or SOI, with high temperatures during the dry season and early wet season negatively influencing survival. These results suggest that, even for species adapted to hot environments, further temperature increases may threaten the persistence of local populations in the absence of distributional shifts.

Research areas: Ecosystems
Data-driven quantification of nitrogen enrichment impact on Northern Hemisphere plant biomass (2022)

The production of anthropogenic reactive nitrogen (N) has grown so much in the last century that quantifying the effect of N enrichment on plant growth has become a central question for carbon (C) cycle research. Numerous field experiments generally found that N enrichment increased site-scale plant biomass, although the magnitude of the response and sign varied across experiments. We quantified the response of terrestrial natural vegetation biomass to N enrichment in the Northern Hemisphere (>30N) by scaling up data from 773 field observations (142 sites) of the response of biomass to N enrichment using machine-learning algorithms. N enrichment had a significant and nonlinear effect on aboveground biomass, but a marginal effect on belowground biomass. The most influential variables on the aboveground biomass response were the amount of N applied, mean biomass before the experiment, the treatment duration and soil phosphorus availability. From the machine learning models, we found that N enrichment due to increased atmospheric N deposition during 1993-2010 has enhanced total biomass by 1.10.3 Pg C, in absence of losses from harvest and disturbances. The largest effect of N enrichment on plant growth occurred in northeastern Asia, where N deposition markedly increased. These estimates were similar to the range of values provided by state-of-the-art C-N ecosystem process models. This work provides data-driven insights into hemisphere-scale N enrichment effect on plant biomass growth, which allows to constrain the terrestrial ecosystem process model used to predict future terrestrial C storage.

Research areas: Ecosystems
Greenhouse gas relationships in the Indian summer monsoon plume measured by the CARIBIC passenger aircraft (2010)

Abstract. During the Indian summer monsoon period 2008, regular measurement flights were performed by the CARIBIC aircraft between Germany and India. Measurements included whole air sampling and subsequent analysis for greenhouse gases (CH4, CO2, N2O, SF6) and in-situ measurements of CO, O3, and H2O. For all these tracers a distinct monsoon signature was observed in the longitude range 5080 E south of 40 N at flight altitudes 812.5 km. The formation of a monsoon plume with enhanced mixing ratios was observed for CH4, N2O, SF6, CO and H2O. The plume began to develop in May and persisted through September, and maximum mixing ratios and maximum spatial extension of the plume were observed in August. For CO2 and O3 a minimum was observed. The amplitude of the CO2 seasonal cycle was larger than at comparable latitudes outside the monsoon region, and the CO2 spring maximum was observed with a delay of one month. Different tracer relationships show strong spatial variations across the plume. The comparison with NOAA ground station data shows a clear enhancement for CH4, N2O, SF6 and CO and a decrease in CO2 mixing ratios. Assuming seasonally invariant SF6 emissions based on the EDGAR 4.0 inventory, monthly emissions were estimated for the period JuneSeptember for CH4, N2O, and CO, and the CO2 uptake was estimated. While for N2O an emission decrease during the monsoon period was derived, emissions of CH4 were highest in September indicating a different seasonal cycle of emissions. Net CO2 uptake by the vegetation was largest in September.

Research areas: Greenhouse Gases
Atmospheric composition study based on ship measurements in the Russian Arctic seas in summer 2019 (2020)

Abstract
            
              We present observation results of methane (CH
              4
              ), its isotopic signature (
              13
              C
              CH4
              ) and carbon dioxide (CO
              2
              ) surface concentrations, made aboard the research vessel (R/V) Akademik Mstislav Keldysh in the Russian Arctic seas in summer 2019. The main goal of the study is to determine the possible sources of methane. As a result of the study, localized areas with an increased methane concentration (up to 2092 ppb) in the surface layer are identified. It may be related to the advection of water masses rich in organic matter from the Ob and Yenisei Rivers. In addition, increased methane concentrations (up to 2010 ppb) are observed in the Kara Sea near the Yamal Peninsula, where gas deposits are concentrated, and active methane emissions from wetland ecosystems are noted. We conclude that the average concentration of methane in surface air in the Arctic seas is determined mainly by large-scale transport of air masses.

Research areas: Greenhouse Gases
Global CO2 Consumption by Silicate Rock Chemical Weathering: Its Past and Future (2021)

Silicate rock weathering maintains a stable and long term absorption of CO<SUB>2</SUB>. However, the magnitude, spatial pattern, and evolution characteristics of global silicate rock weathering carbon sink (SCS) remain unclear. To solve this problem, based on high precision hydrometeorological data (1996-2017) and CMIP5 data (2041-2060), using the Celine model, we calculated the global silicate rock weathering carbon sink flux (SCSF) magnitude and spatio temporal distribution for 1996-2017. We also predicted the SCSF under two future greenhouse gas emission scenarios (RCP 4.5 and RCP 8.5). Then, we produced a spatial data set (0.5 × 0.5) of global SCSF from 1996 to 2017 and found that the global average annual SCSF was 1.67 t/km<SUP>2</SUP>/yr, and the SCS was 127.11 Tg/yr. In particular, Brazil's silicate rock contribution accounts for nearly a quarter of the global SCS (24.41%). Although the GEM CO<SUB>2</SUB> model is now widely used, the SCSF, without considering the temperature, may be overestimated by 5.4%, and the maximum contribution of temperature to it can reach 240 kg/km<SUP>2</SUP>/yr. Moreover, the global SCS is now showing a downward trend, but the global emission of greenhouse gases in the future (2041-2060) will continue to increase the carbon sink capacity (23.8%) due to temperature changes. In summary, we have produced a set of high resolution spatiotemporal data of the past and the future. The above results fill up the large scale data gap of SCSF and provide a scientific basis for quantitatively assessing the impact of climate change on SCS.

Research areas: Greenhouse Gases
Under-reporting of greenhouse gas emissions in US cities (2021)

Cities dominate greenhouse gas emissions. Many have generated self-reported emission inventories, but their value to emissions mitigation depends on their accuracy, which remains untested. Here, we compare self-reported inventories from 48 US cities to independent estimates from the Vulcan carbon dioxide emissions data product, which is consistent with atmospheric measurements. We found that cities under-report their own greenhouse gas emissions, on average, by 18.3% (range: 145.5% to +63.5%)  a difference which if extrapolated to all U.S. cities, exceeds Californias total emissions by 23.5%. Differences arise because city inventories omit particular fuels and source types and estimate transportation emissions differently. These results raise concerns about self-reported inventories in planning or assessing emissions, and warrant consideration of the new urban greenhouse gas information system recently developed by the scientific community.

Research areas: Greenhouse Gases