scholarly journals Variation in Anatomical Characteristics in Leaves of Pecan Seedstocks from Mexico and the United States

2011 ◽  
Vol 136 (2) ◽  
pp. 103-108 ◽  
Author(s):  
Madhulika Sagaram ◽  
Leonardo Lombardini ◽  
L.J. Grauke
Keyword(s):  
East Coast ◽  
Stomatal Density ◽  
The United States ◽  
Carya Illinoinensis ◽  
Annual Precipitation ◽  
Stomatal Index ◽  
Longitudinal Gradient ◽  
Water Losses ◽  
Single Location ◽  
Natural Range

Leaf anatomical traits of Mexican and U.S. pecan [Carya illinoinensis (Wangenh.) K. Koch] seedstocks grown in a single location were studied to determine patterns of ecogeographic variation within the natural range. Stomatal density was uniform among open-pollinated seedlings of a common maternal parent with twofold differences in stomatal density separating some seedstocks. There was an inverse relationship between stomatal density and epidermal cell density. Stomatal density and stomatal index of Mexican seedstocks were related to longitude and annual precipitation of origin. Stomatal density increased along the longitudinal gradient toward the east coast of Mexico; seedstocks originating from areas on the east coast of Mexico had greater stomatal density than seedstocks originating from the drier areas on the west coast. Stomatal density and stomatal index did not follow a pattern along latitude or longitude in the U.S. seedstocks. Although isotopic carbon (13C) discrimination did not vary greatly in Mexican seedstocks, the reduction in stomatal density in pecan trees from areas with reduced annual precipitation suggest the presence of an anatomical feature to reduce water losses.

scholarly journals Variation in Leaf Anatomy of Pecan Cultivars from Three Ecogeographic Locations

2007 ◽  
Vol 132 (5) ◽  
pp. 592-596 ◽  
Author(s):  
Madhulika Sagaram ◽  
Leonardo Lombardini ◽  
L.J. Grauke
Keyword(s):  
Cell Density ◽  
Epidermal Cell ◽  
Stomatal Density ◽  
Carya Illinoinensis ◽  
Trichome Density ◽  
Stomatal Index ◽  
Cultivar Development ◽  
Natural Range ◽  
The Stability

An assessment of leaf anatomic traits of pecan [Carya illinoinensis (Wangenh.) C. Koch] cultivars (Pawnee, Mohawk, and Starking Hardy Giant) collected from three locations (Tifton, GA; Chetopa, KS; and Stillwater, OK) was conducted to provide an understanding of patterns of ecogeographical variation within the natural range. Acetate casts of representative leaves were prepared for microscopic characterization of epidermal traits (stomatal density, stomatal index, and epidermal cell density). There were differences among the three pecan cultivars at the same location, but there were no differences in stomatal density within the same cultivar grown at three distinct locations. The stomatal density of ‘Pawnee’ leaves (404 stomata/mm2) was intermediate between that of ‘Mohawk’ (363 stomata/mm2) and ‘Starking Hardy Giant’ (463 stomata/mm2). ‘Pawnee’ had the greatest epidermal cell density (2511 cells/mm2) whereas ‘Starking Hardy Giant’ showed the least (1414 cells/mm2). Within a location, stomatal index differed significantly among cultivars, with ‘Starking Hardy Giant’ having a greater stomatal index than the other two cultivars. There were no differences in stomatal index across locations. ‘Mohawk’ had the greatest trichome density (18.92 trichomes/mm2) whereas ‘Starking Hardy Giant’ had the lowest (9.6 trichomes/mm2). The study suggests that differences in stomatal density and epidermal cell density in pecans are cultivar specific rather than being determined by environmental factors. The stability of certain leaf anatomic characteristics, such as stomatal and epidermal cell density, for pecan cultivars grown at different locations confirms that these traits can be used for screening provenances with desirable leaf anatomic characteristics for breeding and cultivar development.

scholarly journals Variation in Leaf Anatomical Traits of Pecan Cultivars

HortScience ◽  
2006 ◽  
Vol 41 (4) ◽  
pp. 999E-1000
Author(s):  
Madhulika Sagaram ◽  
Leonardo Lombardini ◽  
Larry Grauke
Keyword(s):  
Geographic Variation ◽  
Cell Density ◽  
Epidermal Cell ◽  
Stomatal Density ◽  
Epidermal Cells ◽  
Stomatal Index ◽  
Natural Range

An assessment of anatomical traits of pecan cultivars (`Pawnee', `Mohawk', and `Starking hardy giant') collected from three locations (Tifton, Ga.; Chetopa, Kans.; and Stillwater, Okla.) was conducted at Texas A&M University. The objective of the study was to provide an understanding of patterns of geographic variation within the natural range for anatomical (stomatal density, stomatal index, and epidermal cell density) traits. Microscopy using acetate casts was used as the means to investigate the patterns of variation in the epidermal characteristics of pecan leaf. `Starking hardy giant' had the greatest number of stomates/cm2 (46,229, 47,807, and 45,990 at Tifton, Chetopa, and Stillwater, respectively) while `Mohawk' had the least (37,397, 36,217, and 35,305). `Pawnee' had the greatest number of epidermal cells/cm2 (251,806, 250,098 and 254,883 at Tifton, Chetopa, and Stillwater, respectively) while `Starking hardy giant' had the least (141,699, 138,405, and 142,155). Differences in stomatal index were observed between the three cultivars at Tifton and Stillwater. No differences in stomatal index were observed between `Pawnee' and `Mohawk' at Chetopa. The study showed that stomatal density as well as epidermal cell density of all the tested cultivars were significantly different (P < 0.05) at a particular location but no differences were observed in a given cultivar grown at different locations.

scholarly journals Economic damages from Hurricane Sandy attributable to sea level rise caused by anthropogenic climate change

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Benjamin H. Strauss ◽  
Philip M. Orton ◽  
Klaus Bittermann ◽  
Maya K. Buchanan ◽  
Daniel M. Gilford ◽  
...  
Keyword(s):  
Climate Change ◽  
Sea Level Rise ◽  
Sea Level ◽  
East Coast ◽  
The United States ◽  
Hurricane Sandy ◽  
Water Levels ◽  
Anthropogenic Climate Change ◽  
Economic Damage ◽  
Sea Levels

AbstractIn 2012, Hurricane Sandy hit the East Coast of the United States, creating widespread coastal flooding and over $60 billion in reported economic damage. The potential influence of climate change on the storm itself has been debated, but sea level rise driven by anthropogenic climate change more clearly contributed to damages. To quantify this effect, here we simulate water levels and damage both as they occurred and as they would have occurred across a range of lower sea levels corresponding to different estimates of attributable sea level rise. We find that approximately $8.1B ($4.7B–$14.0B, 5th–95th percentiles) of Sandy’s damages are attributable to climate-mediated anthropogenic sea level rise, as is extension of the flood area to affect 71 (40–131) thousand additional people. The same general approach demonstrated here may be applied to impact assessments for other past and future coastal storms.

Nearshore wave energy resource characterization along the East Coast of the United States

2021 ◽  
Vol 172 ◽  
pp. 1212-1224
Author(s):  
Seongho Ahn ◽  
Vincent S. Neary ◽  
Mohammad Nabi Allahdadi ◽  
Ruoying He
Keyword(s):  
United States ◽  
Wave Energy ◽  
East Coast ◽  
Energy Resource ◽  
The United States

scholarly journals Italianness in the United States between migrants’ informal gardening practices and agricultural diplomacy (1880–1912)

Modern Italy ◽  
2021 ◽  
pp. 1-17
Author(s):  
Gilberto Mazzoli
Keyword(s):  
United States ◽  
Environmental History ◽  
Rural Areas ◽  
Food Production ◽  
East Coast ◽  
The United States ◽  
Southern United States ◽  
Mass Migration ◽  
Us Cities ◽  
Political Radicalism

During the Age of Mass Migration more than four million Italians reached the United States. The experience of Italians in US cities has been widely explored: however, the study of how migrants adjusted in relation to nature and food production is a relatively recent concern. Due to a mixture of racism and fear of political radicalism, Italians were deemed to be undesirable immigrants in East Coast cities and American authorities had long perceived Italian immigrants as unclean, unhealthy and carriers of diseases. As a flipside to this narrative, Italians were also believed to possess a ‘natural’ talent for agriculture, which encouraged Italian diplomats and politicians to propose the establishment of agricultural colonies in the southern United States. In rural areas Italians could profit from their agricultural skills and finally turn into ‘desirable immigrants’. The aim of this paper is to explore this ‘emigrant colonialism’ through the lens of environmental history, comparing the Italian and US diplomatic and public discourses on the potential and limits of Italians’ agricultural skills.

Keeping Black Girls in School: A Systematic Review of Opportunities to Address Exclusionary Discipline Disparity

2021 ◽  
pp. 215336872098889
Author(s):  
Lynn A. Addington
Keyword(s):  
Systematic Review ◽  
Policy Development ◽  
The United States ◽  
Black Girls ◽  
Research Note ◽  
Future Research ◽  
Exclusionary Discipline ◽  
Girls Of Color ◽  
Single Location ◽  
Trauma Informed

A punitive legacy of the responses to school shootings in the United States is the expansion of exclusionary discipline. Black girls have disproportionately experienced this form of punishment as compared to white girls and non-Black girls of color. A small, but growing, body of research has examined the patterns and causes of this disparity. Current studies have made suggestions for possible solutions to address this disparity, but these recommendations are not readily accessible in a single location. A catalogue of these ideas could provide a useful foundation for policy development and evaluation. The present research note seeks to generate this resource by conducting a systematic review to identify and categorize recommendations aimed at reducing the discipline disparity experienced by Black girls. Based on this review, four categories emerged that center around: (1) culturally competent school programs, (2) enhanced teacher training, (3) spaces at school for empowering Black girls, and (4) trauma-informed student policies. This research note discusses these categories of recommendations using an intersectional framework and concludes with a summary of next steps to guide future research and policy work to address the disproportionate use of exclusionary discipline against Black girls.

scholarly journals Changes in U.S. East Coast Cyclone Dynamics with Climate Change

2015 ◽  
Vol 28 (2) ◽  
pp. 468-484 ◽  
Author(s):  
Christopher G. Marciano ◽  
Gary M. Lackmann ◽  
Walter A. Robinson
Keyword(s):  
Climate Change ◽  
Boundary Conditions ◽  
Potential Vorticity ◽  
East Coast ◽  
The United States ◽  
Sea Level Pressure ◽  
Cyclone Intensity ◽  
Field Amplification ◽  
Lateral Boundary Conditions ◽  
Relative Potential

Abstract Previous studies investigating the impacts of climate change on extratropical cyclones have primarily focused on changes in the frequency, intensity, and distribution of these events. Fewer studies have directly investigated changes in the storm-scale dynamics of individual cyclones. Precipitation associated with these events is projected to increase with warming owing to increased atmospheric water vapor content. This presents the potential for enhancement of cyclone intensity through increased lower-tropospheric diabatic potential vorticity generation. This hypothesis is tested using the Weather Research and Forecasting Model to simulate individual wintertime extratropical cyclone events along the United States East Coast in present-day and future thermodynamic environments. Thermodynamic changes derived from an ensemble of GCMs for the IPCC Fourth Assessment Report (AR4) A2 emissions scenario are applied to analyzed initial and lateral boundary conditions of observed strongly developing cyclone events, holding relative humidity constant. The perturbed boundary conditions are then used to drive future simulations of these strongly developing events. Present-to-future changes in the storm-scale dynamics are assessed using Earth-relative and storm-relative compositing. Precipitation increases at a rate slightly less than that dictated by the Clausius–Clapeyron relation with warming. Increases in cyclone intensity are seen in the form of minimum sea level pressure decreases and a strengthened 10-m wind field. Amplification of the low-level jet occurs because of the enhancement of latent heating. Storm-relative potential vorticity diagnostics indicate a strengthening of diabatic potential vorticity near the cyclone center, thus supporting the hypothesis that enhanced latent heat release is responsible for this regional increase in future cyclone intensity.

scholarly journals Ocean data portals: Performing a new infrastructure for ocean governance

2019 ◽  
Vol 37 (3) ◽  
pp. 484-503 ◽  
Author(s):  
Noëlle Boucquey ◽  
Kevin St. Martin ◽  
Luke Fairbanks ◽  
Lisa M Campbell ◽  
Sarah Wise
Keyword(s):  
United States ◽  
Spatial Planning ◽  
East Coast ◽  
The United States ◽  
Marine Spatial Planning ◽  
Critical Cartography ◽  
Third Phase ◽  
Ocean Governance ◽  
The World ◽  
New Infrastructure

We are currently in what might be termed a “third phase” of ocean enclosures around the world. This phase has involved an unprecedented intensity of map-making that supports an emerging regime of ocean governance where resources are geocoded, multiple and disparate marine uses are weighed against each other, spatial tradeoffs are made, and exclusive rights to spaces and resources are established. The discourse and practice of marine spatial planning inform the contours of this emerging regime. This paper examines the infrastructure of marine spatial planning via two ocean data portals recently created to support marine spatial planning on the East Coast of the United States. Applying theories of ontological politics, critical cartography, and a critical conceptualization of “care,” we examine portal performances in order to link their organization and imaging practices with the ideological and ontological work these infrastructures do, particularly in relation to environmental and human community actors. We further examine how ocean ontologies may be made durable through portal use and repetition, but also how such performances can “slip,” thereby creating openings for enacting marine spatial planning differently. Our analysis reveals how portal infrastructures assemble, edit, and visualize data, and how it matters to the success of particular performances of marine spatial planning.

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