Climate Response of a Dwarfed Population of Quercus marilandica in Central Illinois, United States

2021 ◽  
Vol 83 (1) ◽  
pp. 139-147
Author(s):  
Trevis J. Matheus
Keyword(s):  
United States ◽  
Climate Response ◽  
Quercus Marilandica ◽  
Central Illinois

scholarly journals Survival of Cercospora sojina on Soybean Leaf Debris in Illinois

2014 ◽  
Vol 15 (3) ◽  
pp. 92-96 ◽  
Author(s):  
Guirong Zhang ◽  
Carl A. Bradley
Keyword(s):  
United States ◽  
Southern Illinois ◽  
Cercospora Sojina ◽  
North Central ◽  
East Central ◽  
The North ◽  
Central United States ◽  
Soybean Leaf ◽  
Soybean Leaves ◽  
Central Illinois

Historically, frogeye leaf spot (FLS, caused by Cercospora sojina) of soybean has been observed more frequently in the southern United States than the north-central United States. However, in recent years, FLS field observations have increased in the north-central United States. To better understand the survival rate of C. sojina in Illinois, a field study was conducted at three locations: Monmouth (west-central Illinois), Urbana (east-central Illinois), and Dixon Springs (southeastern Illinois). At each location, soybean leaves affected by FLS were placed at depths of 0, 10, and 20 cm and retrieved at different durations up to 24 months. To determine the viability of C. sojina in the collected leaves, a greenhouse bioassay was used. Survival of C. sojina declined equally with time at all three locations through 19 months. After 24 months, C. sojina from leaves that had been placed at Monmouth and Urbana were no longer viable, whereas leaves that had been placed at Dixon Springs produced viable inoculum. Depth of leaf placement had no effect on survival of C. sojina at any of the locations. These results suggest that planting a nonhost crop for two years in central Illinois will reduce levels of C. sojina inoculum to a negligible amount; however, soybean farmers in southern Illinois may need a longer rotation for FLS management. Accepted 10 May 2014. Published 23 July 2014.

scholarly journals Climate Response to Anomalously Large and Small Atlantic Warm Pools during the Summer

2008 ◽  
Vol 21 (11) ◽  
pp. 2437-2450 ◽  
Author(s):  
Chunzai Wang ◽  
Sang-Ki Lee ◽  
David B. Enfield
Keyword(s):  
United States ◽  
North Atlantic ◽  
North Pacific ◽  
Moisture Transport ◽  
Wind Shear ◽  
Vertical Wind Shear ◽  
Climate Response ◽  
Hurricane Activity ◽  
Static Instability ◽  
Low Level Jet

Abstract This paper uses the NCAR Community Atmospheric Model to show the influence of Atlantic warm pool (AWP) variability on the summer climate and Atlantic hurricane activity. The model runs show that the climate response to the AWP’s heating extends beyond the AWP region to other regions such as the eastern North Pacific. Both the sea level pressure and precipitation display a significant response of low (high) pressure and increased (decreased) rainfall to an anomalously large (small) AWP, in areas with two centers located in the western tropical North Atlantic and in the eastern North Pacific. The rainfall response suggests that an anomalously large (small) AWP suppresses (enhances) the midsummer drought, a phenomenon with a diminution in rainfall during July and August in the region around Central America. In response to the pressure changes, the easterly Caribbean low-level jet is weakened (strengthened), as is its westward moisture transport. An anomalously large (small) AWP weakens (strengthens) the southerly Great Plains low-level jet, which results in reduced (enhanced) northward moisture transport from the Gulf of Mexico to the United States east of the Rocky Mountains and thus decreases (increases) the summer rainfall over the central United States, in agreement with observations. An anomalously large (small) AWP also reduces (enhances) the tropospheric vertical wind shear in the main hurricane development region and increases (decreases) the moist static instability of the troposphere, both of which favor (disfavor) the intensification of tropical storms into major hurricanes. Since the climate response to the North Atlantic SST anomalies is primarily forced at low latitudes, this study implies that reduced (enhanced) rainfall over North America and increased (decreased) hurricane activity due to the warm (cool) phase of the Atlantic multidecadal oscillation may be partly due to the AWP-induced changes of the northward moisture transport and the vertical wind shear and moist static instability associated with more frequent large (small) summer warm pools.

Effects of temperature regime and fertilization on nitrogenase activity of black alder seedlings during autumn in Illinois, U.S.A.

1989 ◽  
Vol 19 (12) ◽  
pp. 1644-1647 ◽  
Author(s):  
Benoît Côté ◽  
Jeffrey O. Dawson
Keyword(s):  
United States ◽  
Nitrogen Fertilization ◽  
Nitrogenase Activity ◽  
Natural Light ◽  
Light Conditions ◽  
Black Alder ◽  
Effects Of Temperature ◽  
Freezing Temperatures ◽  
Central Illinois ◽  
Fertilizer Solution

A pot experiment was conducted to determine the effects of two regimes of temperature and fertilization on nitrogenase activity (acetylene reduction) of naturalized black alder (Alnusglutinosa (L.) Gaertn.) seedlings during autumn in central Illinois, United States. An equal number of Frankia-nodulated plants were fertilized with either a complete or a nitrogen-free fertilizer solution. After 3 months of growth in a glasshouse, half of the plants in each fertilization group were transferred outside in mid-September. Rates of C2H2 reduction decreased throughout autumn for plants in all treatments, although exposure to freezing temperatures accelerated the decline of nitrogenase activity. Alders that did not receive nitrogen fertilization were still reducing C2H2 under natural light conditions in the heated glasshouse on December 10 at a rate of 7.5 nmol•mg−1•h−1. Compared with alders not receiving mineral nitrogen, complete fertilization resulted in a 45% reduction of initial autumnal rates of C2H2 reduction and early inactivity of nitrogenase. Leaf senescence and leaf abscission of naturalized black alder were not induced by decreasing photoperiod alone in Illinois. We conclude that N2 fixation of black alder in Illinois can proceed late into the autumn as long as green leaves remain attached to the plant and nodules are not subjected to low and freezing temperatures.

scholarly journals Improving our Understanding of Helicoverpa zea Migration in the Midwest: Assessment of Source Populations

2007 ◽  
Vol 8 (1) ◽  
pp. 63 ◽  
Author(s):  
Michael A. Sandstrom ◽  
David Changnon ◽  
Brian R. Flood
Keyword(s):  
United States ◽  
Helicoverpa Zea ◽  
Source Region ◽  
Corn Earworm ◽  
Drop Out ◽  
Eastern United States ◽  
Pressure System ◽  
Favorable Weather ◽  
Central Illinois ◽  
Frontal Boundary

Corn earworm (Helicoverpa zea) (CEW) generally are not able to overwinter annually in the Upper Midwest, thus they must migrate northward to affect the primary vegetable-growing locations in this area. Migration of CEW is highly dependent on the weather. Provided a source region in the southern United States, migration of CEW from south to north appeared to occur when a high-pressure system was located in the eastern United States and a low-pressure system and attendant frontal boundary was observed to the east of the Rocky Mountains and/or northern plains states. Southerly wind flow located west of the high and east of the low forms an “insect pump.” Convection cells allowed CEW to lift and advance from their source region northward in the low-level insect pump. When CEW encountered an area of downward motion during their northward flight, such as a frontal boundary or a light precipitation area, they had a tendency to “drop out” of the sky into fields below, an area referred to as the “Drop Zone.” Favorable weather patterns for CEW migration and subsequent infestation of fields in north-central Illinois were confirmed by high CEW trap counts at Rochelle over the last four decades. Accepted for publication 5 September 2006. Published 19 July 2007.

Application of a Simple Cold Stub to the Direct Observation of Frozen Hydrated Sand

1973 ◽  
Vol 31 ◽  
pp. 212-213
Author(s):  
John M. Wehrung ◽  
Richard J. Harniman
Keyword(s):  
United States ◽  
Surface Water ◽  
Direct Observation ◽  
Controlled Study ◽  
Clay Particles ◽  
Organic Debris ◽  
Rock Formations ◽  
Water Tables ◽  
Permeable Rock ◽  
Natural Means

Water tables in aquifer regions of the southwest United States are dropping off at a rate which is greater than can be replaced by natural means. It is estimated that by 1985 wells will run dry in this region unless adequate artificial recharging can be accomplished. Recharging with surface water is limited by the plugging of permeable rock formations underground by clay particles and organic debris.A controlled study was initiated in which sand grains were used as the rock formation and water with known clay concentrations as the recharge media. The plugging mechanism was investigated by direct observation in the SEM of frozen hydrated sand samples from selected depths.

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