Elementa-Science of the Anthropocene最新文献

{"title":"Microbial community response to drought depends on crop","authors":"Jennifer M. Jones, Emma Lauren Boehm, K. Kahmark, J. Lau, Sarah Evans","doi":"10.1525/elementa.2021.00110","DOIUrl":"https://doi.org/10.1525/elementa.2021.00110","url":null,"abstract":"Growing season drought can be devastating to crop yields. Soil microbial communities have the potential to buffer yield loss under drought through increasing plant drought tolerance and soil water retention. Microbial inoculation on agricultural fields has been shown to increase plant growth, but few studies have examined the impact of microbial inoculation on plant and soil microbial drought tolerance. We conducted a rainout shelter experiment and subsequent greenhouse experiment to explore 3 objectives. First, we evaluated the performance of a large rainout shelter design for studying drought in agricultural fields. Second, we tested how crop (corn vs. soybean) and microbial inoculation alter the response of soil microbial composition, diversity, and biomass to drought. Third, we tested whether field inoculation treatments and drought exposure altered microbial communities in ways that promote plant drought tolerance in future generations. In our field experiment, the effects of drought on soil bacterial composition depended on crop type, while drought decreased bacterial diversity in corn plots and drought decreased microbial biomass carbon in soybean plots. Microbial inoculation did not alter overall microbial community composition, plant growth, or drought tolerance despite our efforts to address common barriers to inoculation success. Still, a history of inoculation affected growth of future plant generations in the greenhouse. Our study demonstrates the importance of plant species in shaping microbial community responses to drought and the importance of legacy effects of microbial inoculation.","PeriodicalId":54279,"journal":{"name":"Elementa-Science of the Anthropocene","volume":"1 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66942948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Snow redistribution onto young sea ice: Observations and implications for climate models","authors":"D. Clemens-Sewall, M. Smith, M. Holland, C. Polashenski, D. Perovich","doi":"10.1525/elementa.2021.00115","DOIUrl":"https://doi.org/10.1525/elementa.2021.00115","url":null,"abstract":"Vertical heat conduction through young ice is a major source of wintertime sea ice growth in the Arctic. However, field observations indicate that young ice preferentially accumulates wind-blown snow, resulting in greater snow thickness on young ice than would be expected from precipitation alone, and hence greater snow thickness on young ice than climate models represent. As snow has a low thermal conductivity, this additional snow thickness due to redistribution will reduce the actual heat conduction. We present new observations from the Multidisciplinary drifting Observatory for the Study of Arctic Climate Expedition which show that young ice rapidly accumulates a snow thickness of 2.5–8 cm, when wind-blown snow is available from the nearby mature ice. By applying a simple redistribution scheme and heat flux model to simulated conditions from the Community Earth System Model 2.0, we suggest that neglecting this snow redistribution onto young ice could result in the potential overestimation of conductive heat flux—and hence ice growth rates—by 3–8% on average in the Arctic in the winter in the absence of climate feedbacks. The impacts of snow redistribution are highest in the springtime and in coastal regions.","PeriodicalId":54279,"journal":{"name":"Elementa-Science of the Anthropocene","volume":"1 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66943122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Grounding a global tool—Principles and practice for agroecological assessments inspired by TAPE","authors":"S. Namirembe, W. Mhango, R. Njoroge, Frank Tchuwa, K. Wellard, R. Coe","doi":"10.1525/elementa.2022.00022","DOIUrl":"https://doi.org/10.1525/elementa.2022.00022","url":null,"abstract":"In 2018, the United Nations Food and Agriculture Organization (FAO) described agroecology in terms of 10 Elements. Using this framework, FAO then designed the Tool for Agroecology Performance Evaluation (TAPE) for assessment of the agroecological state of farms and landscapes as part of their mission to produce globally comparable data. A network of 11 agroecology research project teams working in Malawi, Tanzania, Kenya, and Uganda investigated the use of TAPE for their own agroecological assessment needs through a series of workshops and practice, including a field workshop with farmers in Uganda. The key lesson learnt was that there are inspirations to draw from TAPE, including the stepwise approach, rapid assessment across all 10 agroecology elements, and the use of simple rating scales. However, the teams also concluded that TAPE could not be used in their contexts as a readymade tool for three main reasons. First, objectives matter—there are multiple reasons for carrying out an agroecological assessment, and the tool used needs tuning to those objectives. Second, the ethical value of codesign means that those engaged need to be served by the assessment and be involved in negotiating its design. Third, localization is necessary—the same precise set of concepts, terminology, indicators, and scales in TAPE are not relevant in all contexts, and this localization can be done using the codesign process. Based on this experience, we proposed a set of 10 principles that could underlie any agroecological assessment. We further outlined, and project teams used, a process for putting the principles into practice and planning such an agroecological assessment. It involves the following steps (1) Identifying the objectives of assessment within the broader project and community goals, (2) Choosing the approach and breadth of the assessment scheme, (3) Designing details of the assessment scheme, (4) Testing and revising, (5) Implementation, and (6) Reflection and sharing learnings. The steps have potential application by researchers, development agents, and farmer organizations to assess the agroecological status of farms and landscapes in different contexts. Together, these take inspiration from TAPE but should lead to tools that are adapted to the specific purpose, context, and capacities where they will be used.","PeriodicalId":54279,"journal":{"name":"Elementa-Science of the Anthropocene","volume":"1 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66943323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Satellite observations of NO2 indicate legacy impacts of redlining in U.S. Midwestern cities","authors":"Elizabeth Hrycyna, Jennings G. A. Mergenthal, Saiido Noor, M. Heskel","doi":"10.1525/elementa.2022.00027","DOIUrl":"https://doi.org/10.1525/elementa.2022.00027","url":null,"abstract":"Redlining was a practice of financial discrimination in the mid-20th century in which banks refused loans or increased interest rates based on the grade of an applicant’s neighborhood as designated by the federally sponsored Home Owner’s Lending Commission (HOLC). The HOLC primarily graded neighborhoods from “A” (best) to “D” (hazardous) based on characteristics including the racial demographics and economic status of the residents, with neighborhoods with higher percentages of non-white and/or recent immigrant residents given lower grades; this and similar discriminatory practices can be traced to modern-day economic and environmental inequalities between neighborhoods. The legacy of redlining and related housing discrimination on modern-day urban air quality, which presents a significant threat to public health, remains an important issue in addressing environmental injustice in U.S. cities. In our study, we used remotely sensed estimates of the air pollutant nitrogen dioxide (NO2) collected with the TROPOMI satellite sensor, and shapefiles of redlined neighborhoods, to determine whether air quality varies among historic HOLC grades in 11 U.S. Midwestern metropolitan areas. This approach allowed us to test these tools for within-city analysis of NO2 for which high spatial and temporal resolution measurements are not often available, despite their importance for monitoring impacts on human health. We found that NO2 levels were as much as 16% higher in neighborhoods that were graded “D” compared to those graded “A” (as in Chicago), with the mean difference across all cities an increase of 7.3% ± 5.9%. These results present evidence of persistent modern-day inequality in urban air quality associated with historic discriminatory policies and should be used as an argument for government action improving air quality in neighborhoods that were poorly graded by the HOLC.","PeriodicalId":54279,"journal":{"name":"Elementa-Science of the Anthropocene","volume":"1 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66943432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Does the government procurement market favor corporate social responsibility in a weak institution? Evidence from China","authors":"Ran Rong, Wang Qiqi, Zhiyang Liu, Shaobo Long","doi":"10.1525/elementa.2022.00016","DOIUrl":"https://doi.org/10.1525/elementa.2022.00016","url":null,"abstract":"This study investigates, in the context of a weak institution, the single and interactive effects of firms’ nonmarket strategies in China’s government procurement market. Based on transaction cost and signal theory, using data pertaining to Chinese government procurement contracts from 2016 to 2018, this study also provides evidence that superior corporate social responsibility (CSR) performance enables firms to obtain more government procurement contracts. However, the effect is only significant in non-state-owned enterprises. Considering the interaction effect of corporate political activity (CPA) and CSR in business to government (B2G) markets, this study finds that CPA, characterized by the political attributes of executives, enhances the signal effect of CSR in B2G markets. Further heterogeneity analysis indicates that CSR’s signal effect diminishes over time and is enhanced with high industry competition. Our findings provide new insights on nonmarket mechanisms (such as CSR), through which firms competing in China’s B2G market can compensate for the weak institution.","PeriodicalId":54279,"journal":{"name":"Elementa-Science of the Anthropocene","volume":"1 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66943444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stratospheric aerosol injection may impact global systems and human health outcomes","authors":"S. M. Tracy, J. Moch, S. Eastham, J. Buonocore","doi":"10.1525/elementa.2022.00047","DOIUrl":"https://doi.org/10.1525/elementa.2022.00047","url":null,"abstract":"Solar radiation management (SRM) is a climate engineering strategy to reduce temperature increases due to global climate change. The most well-researched SRM methodology is stratospheric aerosol injection (SAI), which involves increasing the concentration of aerosol particles in the stratosphere to reduce the amount of solar radiation reaching Earth’s surface. The most considered and heavily researched aerosol for SAI is sulfate. SAI has been extensively modeled using various climate scenarios and investigated using data from previous volcanic eruptions, which provide an analog of the climate effects of SAI. Prior research has determined that SAI will not only decrease global temperatures but is likely to have direct impacts on ecosystem and public health. This review seeks to investigate the various ways by which SAI may impact global public health outcomes related to hydrologic cycling, atmospheric chemical cycling, frequency of natural disasters, food system disruptions, and ecological health through the pathways of water, air, soil, and biota. SAI has the potential to decrease negative health outcomes associated with rising temperatures but may have a myriad of impacts on global environmental systems. Anthropogenically altering the global climate, through both the release of greenhouse gases or through climatic engineering, has unknown consequences, many of which will likely impact global health and quality of life. A more holistic approach is necessary to understand the relative benefits and harms in using SAI as compared to the implication of global climate change.","PeriodicalId":54279,"journal":{"name":"Elementa-Science of the Anthropocene","volume":"1 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66943819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Low NOX and high organic compound emissions from oilfield pumpjack engines","authors":"S. Lyman, H. Tran, T. O’Neil, M. Mansfield","doi":"10.1525/elementa.2022.00064","DOIUrl":"https://doi.org/10.1525/elementa.2022.00064","url":null,"abstract":"We measured a comprehensive suite of pollutants emitted from 58 natural gas-fueled pumpjack engines in Utah’s Uinta Basin. Air–fuel equivalence ratio (the ratio of air taken in by the engine to the amount of air needed for combustion of the fuel) was a strong predictor of emissions. Higher air–fuel equivalence ratios led to lower oxides of nitrogen (NOX) emissions and higher emissions of organic compounds. For engines with air–fuel equivalence ratios greater than 3 (34% of 58 total engines tested), a median of 57% of the fuel gas passed through the engine uncombusted, and exhaust gas contained a median of only 3 ppm NOX. Lower air–fuel equivalence ratios were associated with less fuel slip, higher NOX, and the formation of more reactive organic compounds, including alkenes and carbonyls. Average NOX emissions measured in this study were only 9% of average emissions from natural gas-fueled pumpjack engines in a regulatory oil and gas emissions inventory. In contrast, volatile organic compound emissions in the study were 15 times higher than in the inventory. We hypothesize that these discrepancies are due to changes in emissions as engines operate at lower loads and as they age in field conditions. In addition to improving emissions inventories and the effectiveness of related regulatory efforts, this work will improve the ability of photochemical models to simulate the atmospheric impacts of oil and gas development.","PeriodicalId":54279,"journal":{"name":"Elementa-Science of the Anthropocene","volume":"1 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66944516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A polycentric food sovereignty approach to climate resilience in the Philippines","authors":"Amber Heckelman, M. Chappell, Hannah Wittman","doi":"10.1525/elementa.2020.00033","DOIUrl":"https://doi.org/10.1525/elementa.2020.00033","url":null,"abstract":"Enhancing climate resilience in agrarian communities requires improving the underlying socioecological conditions for farmers to engage in adaptation and mitigation strategies, alongside collaborative and redistributive community development to reduce vulnerabilities. To overcome barriers to climate resilience in the Philippines, a grassroots farmer-led organization comprised of resource-poor smallholders, scientists, and nongovernmental organizations have organized a polycentric network over the past 30 years to implement food sovereignty initiatives. We explore the extent to which the network’s decentralized and farmer-led organizational structure; programming and services; promotion of diversified, organic, and agroecological farming systems; and political organizing and advocacy create broadly accessible and diverse pathways for resource-poor smallholders to build climate resilience. We find that the Magsasaka at Siyentipiko para sa Pag-Unlad ng Agrikultura’s (Farmer-Scientist Partnership for Development) polycentric governance approach directly addresses the root causes of vulnerability, particularly in working to reclaim farmer rights and control over resources, connecting local and global struggles, and revitalizing agrobiodiversity and place-based knowledge.","PeriodicalId":54279,"journal":{"name":"Elementa-Science of the Anthropocene","volume":"1 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66937840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatiotemporal evolution of melt ponds on Arctic sea ice","authors":"M. Webster, M. Holland, N. Wright, S. Hendricks, N. Hutter, P. Itkin, B. Light, F. Linhardt, D. Perovich, Ian A. Raphael, M. Smith, Luisa von Albedyll, Jinlun Zhang","doi":"10.1525/elementa.2021.000072","DOIUrl":"https://doi.org/10.1525/elementa.2021.000072","url":null,"abstract":"Melt ponds on sea ice play an important role in the Arctic climate system. Their presence alters the partitioning of solar radiation: decreasing reflection, increasing absorption and transmission to the ice and ocean, and enhancing melt. The spatiotemporal properties of melt ponds thus modify ice albedo feedbacks and the mass balance of Arctic sea ice. The Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition presented a valuable opportunity to investigate the seasonal evolution of melt ponds through a rich array of atmosphere-ice-ocean measurements across spatial and temporal scales. In this study, we characterize the seasonal behavior and variability in the snow, surface scattering layer, and melt ponds from spring melt to autumn freeze-up using in situ surveys and auxiliary observations. We compare the results to satellite retrievals and output from two models: the Community Earth System Model (CESM2) and the Marginal Ice Zone Modeling and Assimilation System (MIZMAS). During the melt season, the maximum pond coverage and depth were 21% and 22 ± 13 cm, respectively, with distribution and depth corresponding to surface roughness and ice thickness. Compared to observations, both models overestimate melt pond coverage in summer, with maximum values of approximately 41% (MIZMAS) and 51% (CESM2). This overestimation has important implications for accurately simulating albedo feedbacks. During the observed freeze-up, weather events, including rain on snow, caused high-frequency variability in snow depth, while pond coverage and depth remained relatively constant until continuous freezing ensued. Both models accurately simulate the abrupt cessation of melt ponds during freeze-up, but the dates of freeze-up differ. MIZMAS accurately simulates the observed date of freeze-up, while CESM2 simulates freeze-up one-to-two weeks earlier. This work demonstrates areas that warrant future observation-model synthesis for improving the representation of sea-ice processes and properties, which can aid accurate simulations of albedo feedbacks in a warming climate.","PeriodicalId":54279,"journal":{"name":"Elementa-Science of the Anthropocene","volume":"1 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66940280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A microbial perspective on the local influence of Arctic rivers and estuaries on Hudson Bay (Canada)","authors":"Carlee Morency, L. Jacquemot, M. Potvin, C. Lovejoy","doi":"10.1525/elementa.2021.00009","DOIUrl":"https://doi.org/10.1525/elementa.2021.00009","url":null,"abstract":"A clear divide typically exists between freshwater and marine microbial communities, with transitional communities found in estuarine zones. The estuarine communities can derive from inflowing rivers and the sea via tidal mixing and incursions or be comprised of unique brackish species, depending on flow regimes and retention time within an estuary. Only a few studies have been carried out in the Arctic, where moderate salinities associated with the influence of seasonal ice melt could potentially favor marine microbes adapted to lower salinities in fresh-to-saltwater transition zones irrespective of river flows and tidal mixing. To test this idea, we examined early summer microbial communities in 2 western Hudson Bay (Canada) river-to-sea systems: the Churchill and Nelson river systems. Both rivers originate from the same headwaters, suggesting similar catchment conditions, but differ in geomorphology and hydroelectric diversions that induce very different flow and stratification regimes. Using amplicons of the V4 region of the 16S rRNA gene, we identified distinct riverine bacterial communities that were significantly different from the 2 associated estuaries and offshore communities. In the much smaller Churchill Estuary, the microbial community showed a marked influence of freshwater microbial species, along with marine influences. In contrast, in the larger high-flow Nelson River Estuary, riverine bacterioplankton were less evident in the estuary, where the marine signal was much stronger. The marine samples in both systems differed somewhat consistently with the phenology of the phytoplankton bloom in the Bay and tended to harbor distinct attached and free-living bacterial communities. Our results highlight the relevance of river flow and estuarine circulation on selection of bacterial species in estuaries, with ecological implications for food web functionality and biogeochemical cycles in the Anthropocene, where flow regimes would be affected by larger climatic variability.","PeriodicalId":54279,"journal":{"name":"Elementa-Science of the Anthropocene","volume":"1 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66940297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}