scholarly journals Variation in Ectosymbiont Assemblages Associated with Rock Pigeons (Columba livia) from Coast to Coast in Canada

Diversity ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 9
Author(s):  
Alexandra Grossi ◽  
Heather Proctor
Keyword(s):  
Columba Livia ◽  
The United States ◽  
Climatic Conditions ◽  
Assemblage Structure ◽  
Meteorological Variables ◽  
Urban Center ◽  
Sampling Locations ◽  
Maximum Temperatures ◽  
Symbiont Species ◽  
Maximum Humidity

When a species colonizes a new area, it has the potential to bring with it an array of smaller-bodied symbionts. Rock Pigeons (Columba livia Gmelin) have colonized most of Canada and are found in almost every urban center. In its native range, C. livia hosts more than a dozen species of ectosymbiotic arthropods, and some of these lice and mites have been reported from Rock Pigeons in the United States. Despite being so abundant and widely distributed, there are only scattered host-symbiont records for rock pigeons in Canada. Here we sample Rock Pigeons from seven locations across Canada from the west to east (a distance of > 4000 km) to increase our knowledge of the distribution of their ectosymbionts. Additionally, because ectosymbiont abundance can be affected by temperature and humidity, we looked at meteorological variables for each location to assess whether they were correlated with ectosymbiont assemblage structure. We found eight species of mites associated with different parts of the host’s integument: the feather dwelling mites Falculifer rostratus (Buchholz), Pterophagus columbae (Sugimoto) and Diplaegidia columbae (Buchholz); the skin mites: Harpyrhynchoides gallowayi Bochkov, OConnor and Klompen, H. columbae (Fain), and Ornithocheyletia hallae Smiley; and the nasal mites Tinaminyssus melloi (Castro) and T. columbae (Crossley). We also found five species of lice: Columbicola columbae (Linnaeus), Campanulotes compar (Burmeister), Coloceras tovornikae Tendeiro, Hohorstiella lata Piaget, and Bonomiella columbae Emerson. All 13 ectosymbiont species were found in the two coastal locations of Vancouver (British Columbia) and Halifax (Nova Scotia). The symbiont species found in all sampling locations were the mites O. hallae, H. gallowayi, T. melloi and T. columbae, and the lice Colu. columbae and Camp. compar. Three local meteorological variables were significantly correlated with mite assemblage structure: annual minimum and maximum temperatures and maximum humidity in the month the pigeon was collected. Two local meteorological variables, annual maximum and average temperatures, were significantly correlated with louse assemblages. Our results suggest that milder climatic conditions may affect richness and assemblage structure of ectosymbiont assemblages associated with Rock Pigeons in Canada.

Winter survival response of canola to meteorological variables and adaptative areas for current canola germplasm in the United States

2021 ◽  
Vol 297 ◽  
pp. 108267
Author(s):  
Mario A. Secchi ◽  
Leonardo M. Bastos ◽  
Michael J. Stamm ◽  
Yancy Wright ◽  
Chris Foster ◽  
...  
Keyword(s):  
United States ◽  
The United States ◽  
Winter Survival ◽  
Meteorological Variables

scholarly journals First Report of Choke Disease Caused by Epichloë typhina on Orchardgrass (Dactylis glomerata) in China

Plant Disease ◽  
2009 ◽  
Vol 93 (6) ◽  
pp. 673-673 ◽  
Author(s):  
C. J. Li ◽  
Z. F. Wang ◽  
N. Chen ◽  
Z. B. Nan
Keyword(s):  
Dactylis Glomerata ◽  
The United States ◽  
Leaf Sheath ◽  
Climatic Conditions ◽  
Disease Spread ◽  
Willamette Valley ◽  
First Report ◽  
Epichloë Typhina ◽  
Pure Cultures ◽  
Choke Disease

Orchardgrass or cocksfoot (Dactylis glomerata L.) has been widely cultivated as a forage crop in many provinces of China (1). It is also a native perennial forage grass, which grows at the edge of forests, shrubs, and mountainous grasslands in Xinjiang and Sichuan (2). In September of 2007, signs of choke disease on orchardgrass were observed in a native grassland under birch woodland near Altai City, Xinjiang, China. Stromata, which formed on culms of diseased grass, enclosing the inflorescence and leaf sheath, were 4.5 to 5.5 mm long, smooth or wrinkled, white and later becoming yellowish or yellow, tuberculate, dry, and covered with perithecia. Inflorescences surrounded by fungal stromata were choked and failed to mature, thus restricting seed production. Pure cultures were obtained by directly scraping stromata from the surface and incubating it on antibiotic potato dextrose agar (PDA). The colonies were cottony, white on the upper surface, and white to yellow on the reverse. The growth rate was 13 to 21 mm per week at 25°C on PDA. Conidia were hyaline, lunate to reniform, and measured 4.1 ± 0.5 × 2.2 ± 0.5 μm. They accumulated in small globose heads at the tips of conidiogenous cells and were produced singly on conidiophores of 13 to 33 μm long and 2.7 to 4.1 μm wide at the base. Internal transcribed spacer (ITS) sequence by BLAST search had 99% similarity with an Epichloë typhina isolate of orchardgrass in Spain (GenBank Accession No. AM262420.1). Cultural characteristics, microscopic examination, and phylogenetic analysis showed that this choke disease on D. glomerata was caused by the fungus E. typhina (Pers.) Tul. & C. Tul. as described by White (4). To our knowledge, this is the first report of E. typhina causing choke disease on orchardgrass in China. The pathogen has been identified in France, England, Germany, Sweden, Switzerland, and the United States (3,4) with the same symptoms as those reported here. In 1997, choke disease was found in 70% of the fields in the Willamette Valley of Oregon, with disease incidences ranging from 0.05 to 28%. It was predicted to increase and spread under the prevailing climatic conditions (3). This new disease report is to provide observational and diagnostic information to help with recognition and prevention of disease spread in orchardgrass cultivation regions of China. References: (1) X. R. Chao et al. Shandong Agric. Sci. 1:7, 2005. (2) S. X. Jia, ed. China Forage Plant Flora. China Agriculture Press, Beijing, 1987. (3) W. F. Pfender and S. C. Alderman. Plant Dis. 83:754, 1999. (4) J. W. White. Mycologia 85:444, 1993.

scholarly journals Process of forming a regional recreation system in the conditions of a border region

2020 ◽  
Vol 164 ◽  
pp. 07028
Author(s):  
Anastasia Vasilieva ◽  
Raisa Belaya
Keyword(s):  
Regional Policy ◽  
Principal Component ◽  
Environmental Safety ◽  
The United States ◽  
Climatic Conditions ◽  
Border Region ◽  
Significant Heterogeneity ◽  
Factor Rotation ◽  
The Face ◽  
Definition Of

Significant heterogeneity of the level of development of the Russian border, including in the field of recreation, imposes requirements for differentiation in the regional policy. Definition of the types of territories helps to solve applied management tasks more effectively. In this context, the factors by which these types were formed are important. To solve this problem, the authors conducted a factor analysis through the principal component method using oblique factor rotation. Three blocks of variables were analyzed that characterize the subjects of the Russian Federation that have land borders on the mainland (including river and lake borders) and sea borders with neighboring countries located on the map clockwise from Norway to the United States (border regions of Russia) for the period from 2010 to 2018. As a result, five factors were identified: the factor of the demand for the services of the recreational system, the factor of the development of the infrastructure of the recreational system in climatic conditions, the environmental safety factor, the factor of investment in the development of the recreational system infrastructure, the factor of the location at the border. The results of the study can be used as a practical tool for developing recommendations in the field of regional policy aimed at development of a recreational system, taking into account the factors determined for each identified group. The results of the study were obtained in the framework of the state task of the IE KarRC RAS on the topic “Institutions and social inequality in the face of global challenges and regional restrictions”.

scholarly journals Burrow casts from the Lystrosaurus-Procolophon Assemblage-zone, Karoo Sequence, South Africa

Koedoe ◽  
1991 ◽  
Vol 34 (1) ◽  
Author(s):  
G.H. Groenewald
Keyword(s):  
United States ◽  
South Africa ◽  
United States Of America ◽  
The United States ◽  
Climatic Conditions ◽  
Desiccation Cracks ◽  
Assemblage Zone

Five types of burrow casts from the Lystrosaurus- Procolophon Assemblage-zone (Palingkloof Member and Katberg Formation, Triassic, Karoo sequence. South Africa) are associated with casts of desiccation cracks and red mudstone. Vertebrate remains of Lystrosaurus sp. and Procolophon sp. indicate that these animals probably made the burrows during the Triassic. It is possible that burrowing was an adaptive advantage during periods of severe and unfavourable climatic conditions. Similar burrow casts were found in the Dicynodon-Theriognathus Assemblage-zone, suggesting a burrowing habit for fauna represented in this zone. In structure, the burrow casts resemble those of Scoyenia, Thalassinoides, Histioderma, Gyrolithes and Planolites reported from Germany, France, Asia, Ireland, Spain and the United States of America.

scholarly journals Characteristics of Xanthomonas cucurbitae Isolates from Pumpkins and Survival of the Bacterium in Pumpkin Seeds

Plant Disease ◽  
2018 ◽  
Vol 102 (9) ◽  
pp. 1779-1784 ◽  
Author(s):  
X. Zhang ◽  
M. Babadoost
Keyword(s):  
The United States ◽  
Culture Collection ◽  
Colony Development ◽  
North Central Region ◽  
North Central ◽  
The North ◽  
Significant Difference ◽  
Optimum Ph ◽  
Pumpkin Seeds ◽  
Maximum Temperatures

This study was conducted to determine characteristics of Xanthomonas cucurbitae, the causal agent of bacterial spot of pumpkin, and survival of the bacterium in pumpkin seeds. Fourteen X. cucurbitae isolates from the north central region of the United States, along with the X. cucurbitae strain 23378 from the American Type Culture Collection, were included in this study. The range of minimum, optimum, and maximum temperatures for colony development of X. cucurbitae were 4 to 6°C, 24 to 30°C, and 34 to 36°C, respectively. Optimum pH for colony development ranged from 6.5 to 8.0. Leaves of 3-week-old pumpkins ‘Howden’ and ‘Dickinson’ were inoculated with X. cucurbitae isolates (108 CFU/ml). There was a significant difference in the postinoculation periods for appearance of bacterial lesions on the leaves among the isolates; however, there was no significant difference in diameters of the lesions on each of the pumpkin cultivar 7 days after inoculation. Four of the isolates caused significantly larger lesions on ‘Dickinson’ leaves than ‘Howden’ leaves. Naturally infected ‘Howden’ pumpkin and inoculated ‘Dickinson’ pumpkin seeds with X. cucurbitae were stored at 4 and 22°C. X. cucurbitae was isolated from both naturally infected and inoculated seeds 24 months after storage at both 4 and 22°C, and the isolated bacteria were pathogenic.

The Imperialism of Free Trade: Lancashire, India, and the Cotton Supply Question, 1861-1865

1966 ◽  
Vol 6 (1) ◽  
pp. 70-96 ◽  
Author(s):  
Peter Harnetty
Keyword(s):  
Free Trade ◽  
The United States ◽  
Climatic Conditions ◽  
Considerable Effort ◽  
Improvement Program ◽  
Alternative Source ◽  
General Validity ◽  
Extensive Program ◽  
The Government ◽  
The Many

It is now more than a decade since John Gallagher and Ronald Robinson first challenged the conventional interpretations of nineteenth-century imperial history and employed the term “The Imperialism of Free Trade” to describe the “ever-extending and intensifying development of overseas regions” — a term which characterizes British imperial policy in the middle decades of the last century. The general validity of this thesis has been illustrated by reference to British policies in India in this period. There was the extensive program of railway construction, financed by British capital at favorable rates of interest guaranteed by the Government of India. There was the manipulation of the Indian tariff in response to pressure from the Lancashire cotton manufacturers. There was the cotton improvement program, the object of which was to relieve Lancashire's dependence on the United States as the major source of its raw cotton. In this case, the desired object was not achieved, despite considerable effort and expenditure sustained over more than a decade. But the approach of civil war in America revived interest in India as an alternative source of supply, notwithstanding the many difficulties that stood in the way. Indian cotton was raised on small holdings as a secondary crop every third or fourth year; its quality was poor; climatic conditions were uncertain; demand was irregular; communications between the cotton-producing areas and the ports were bad; and trade was hampered by lack of a contract law and a bankruptcy act. The Lancashire cotton manufacturers demanded energetic action from the state in overcoming these difficulties.

Environmental Benefits and Concerns of Center-Pivot Irrigation

2017 ◽  
Author(s):  
Leonor Rodriguez Sinobas
Keyword(s):  
20Th Century ◽  
The United States ◽  
Climatic Conditions ◽  
Environmental Benefits ◽  
Surface Irrigation ◽  
Irrigation Systems ◽  
Center Pivot ◽  
Key Issues ◽  
Precision Irrigation ◽  
Control Water

Center-pivot irrigation systems started in the United States in the mid-20th century as an irrigation method which surpassed the traditional surface irrigation methods. At that time, they had the potential to bring about higher irrigation efficiencies with less water consumption although their requirements in energy were higher too. Among their benefits, it is highlighted the feasibility to control water management as well as the application of agro-chemicals dissolved in the irrigation water and thus, center-pivot irrigation systems have spread worldwide. Nevertheless, since the last decade of the 20th century, they are facing actual concerns regarding ecosystem sustainability and water and energy efficiencies. Likewise, the 21st century has brought about the cutting edge issue “precision irrigation” which has made feasible the application of water, fertilizers, and chemicals as the plant demands taking into account variables such as: sprinkler´s pressure, terrain topography, soil variability, and climatic conditions. Likewise, it could be adopted to deal with the current key issues regarding the sustainability and efficiency of the center-pivot irrigation to maintain the agro-ecosystems but still, other issues such as the organic matter incorporation are far to be understood and they will need further studies.

scholarly journals Strong influence of 2000–2050 climate change on particulate matter in the United States: Results from a new statistical model

2016 ◽  
Author(s):  
Lu Shen ◽  
Loretta J. Mickley ◽  
Lee T. Murray
Keyword(s):  
Climate Change ◽  
United States ◽  
Particulate Matter ◽  
Air Quality ◽  
Statistical Model ◽  
The United States ◽  
Anthropogenic Sources ◽  
Meteorological Variables ◽  
Eastern United States ◽  
Low Cloud

Abstract. We use a statistical model to investigate the effect of 2000–2050 climate change on fine particulate matter (PM2.5) air quality across the contiguous United States. By applying observed relationships of PM2.5 and meteorology to the IPCC Coupled Model Intercomparision Project Phase 5 (CMIP5) archives, we bypass many of the uncertainties inherent in chemistry-climate models. Our approach uses both the relationships between PM2.5 and local meteorology as well as the synoptic circulation patterns, defined as the Singular Value Decomposition (SVD) pattern of the spatial correlations between PM2.5 and meteorological variables in the surrounding region. Using an ensemble of 17 GCMs under the RCP4.5 scenario, we project an increase of ~ 1 μg m−3 in annual mean PM2.5 in the eastern US and a decrease of 0.3–1.2 μg m−3 in the Intermountain West by the 2050s, assuming present-day anthropogenic sources of PM2.5. Mean summertime PM2.5 increases as much as 2–3 μg m−3 in the eastern United States due to faster oxidation rates and greater mass of organic carbon from biogenic emissions. Mean wintertime PM2.5 decreases by 0.3–3 μg m−3 over most regions in United States, likely due to the volatilization of ammonium nitrate. Our approach provides an efficient method to calculate the climate penalty or benefit on air quality across a range of models and scenarios. We find that current atmospheric chemistry models may underestimate or even fail to capture the strongly positive sensitivity of monthly mean PM2.5 to temperature in the eastern United States in summer, and may underestimate future changes in PM2.5 in a warmer climate. In GEOS-Chem, the underestimate in monthly mean PM2.5-temperature relationship in the East in summer is likely caused by overly strong negative sensitivity of monthly mean low cloud fraction to temperature in the assimilated meteorology (~ −0.04 K−1), compared to the weak sensitivity implied by satellite observations (±0.01 K−1). The strong negative dependence of low cloud cover on temperature, in turn, causes the modeled rates of sulfate aqueous oxidation to diminish too rapidly as temperatures rise, leading to the underestimate of sulfate-temperature slopes, especially in the South. Our work underscores the importance of evaluating the sensitivity of PM2.5 to its key controlling meteorological variables in climate-chemistry models on multiple timescales before they are applied to project future air quality.

scholarly journals Simulating Hydrological Drought Properties at Different Spatial Units in the United States Based on Wavelet–Bayesian Regression Approach

2012 ◽  
Vol 16 (17) ◽  
pp. 1-23 ◽  
Author(s):  
Ashok K. Mishra ◽  
Vijay P. Singh
Keyword(s):  
United States ◽  
Regression Model ◽  
Climate Models ◽  
Global Climate ◽  
The United States ◽  
Hydrological Drought ◽  
Bayesian Regression ◽  
Global Climate Models ◽  
Meteorological Variables ◽  
The Relationship

Abstract Because of their stochastic nature, droughts vary in space and time, and therefore quantifying droughts at different time units is important for water resources planning. The authors investigated the relationship between meteorological variables and hydrological drought properties using the Palmer hydrological drought index (PHDI). Twenty different spatial units were chosen from the unit of a climatic division to a regional unit across the United States. The relationship between meteorological variables and PHDI was investigated using a wavelet–Bayesian regression model, which enhances the modeling strength of a simple Bayesian regression model. Further, the wavelet–Bayesian regression model was tested for the predictability of global climate models (GCMs) to simulate PHDI, which will also help understand their role for downscaling purposes.

International Wheat Council

1961 ◽  
Vol 15 (2) ◽  
pp. 339-340
Keyword(s):  
World War Ii ◽  
The United States ◽  
Climatic Conditions ◽  
Annual Review ◽  
Producer Price ◽  
Food And Agriculture ◽  
Food And Agriculture Organization ◽  
Price Supports ◽  
The Press ◽  
The World

The International Wheat Council held its 31st session in London from November 7 to 19, 1960, for the purpose of reviewing the world wheat situation in accordance with article 21 of the 1959 International Wheat Agreement. The meeting was attended by representatives of 29 member countries and by observers from the UN Food and Agriculture Organization (FAO) and the European Economic Community. According to the press, the results of the second annual review, published on December 12, 1960, revealed that although climatic conditions had created unusually favorable preconditions for an expansion of the world wheat trade during 1960–61, the world surplus at the end of the season was expected to be larger than ever. The press reported that the cause of the wheat surplus problem was government intervention in production, pricing, and trading. Government measures introduced during and shortly after World War II to meet supply deficiencies in a war-disrupted world had been allowed to continue in effect, although the years since the war had seen growing surpluses. According to reports, there had been few changes in national policies affecting producer price supports in 1960; among 25 cases classified by the Council, supports had been reduced in only two instances, while in six instances they had been raised and in seventeen they had remained unchanged. In the four main wheat exporting countries—the United States, Canada, Argentina, and Australia—the end-of-season carry-overs as of July 31 were expected to reach an unprecedented total of 60.4 million metric tons, 37.3 million metric tons over the normal stock surplus. The ultimate solution of wheat surplus problems, concluded the press, depended on a growing adjustment of national wheat policies to international realities.

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