Tree species distributions related to climatic patterns in Michigan

1987 ◽  
Vol 17 (7) ◽  
pp. 613-629 ◽  
Author(s):  
Shirley R. Denton ◽  
Burton V. Barnes

Relationships between the distributions of major forest species and climatic patterns in Michigan were examined using binary discriminant analysis ordination, Kolmogrov–Smirnov statistics, histograms, and correlation coefficients. Species occurring only in southern Lower Michigan (e.g., sassafras, Sassafrasalbidum (Nutt.) Nees) were strongly associated with warm, long growing seasons that had high night temperatures, low precipitation relative to potential evapotranspiration throughout the summer months, and low heat sums prior to last spring freeze. Species found throughout Lower Michigan but not extending into Upper Michigan (e.g., black oak, Quercusvelutina Lamarck, and white oak, Q. alba L.) had similar associations except that they were not strongly associated with low heat sums prior to last spring freeze. Conifers (e.g., balsam fir, Abiesbalsamea (L.) Miller, and white pine, Pinusstrobus L.) were associated with short growing seasons of highly variable length, high heat sums prior to last spring freeze, high precipitation relative to potential evapotranspiration even in July and August when the difference between precipitation and evapotranspiration was greatest, and low night temperatures relative to daytime temperatures. All species had individualistic correlations with major climatic statistics. Species range limits, where they occurred in the state, were generally simultaneously correlated with more than one climatic variable.

The Condor ◽  
2006 ◽  
Vol 108 (2) ◽  
pp. 377-388 ◽  
Author(s):  
Jeffrey E. Moore ◽  
Robert K. Swihart

Abstract We assessed dietary preference of 14 captive Blue Jays (Cyanocitta cristata) for different food types under different conditions of availability. In four separate feeding trials, we provisioned jays with the following: Trial 1, two nuts each of white oak (Quercus alba), pin oak (Q. palustris), black oak (Q. velutina), northern red oak (Q. rubra), and shagbark hickory (Carya ovata); Trial 2, two small and two large red oak acorns; Trial 3, two germinating and two nongerminating white oak acorns; and Trial 4, one large red oak acorn, one large white oak acorn, and one shagbark hickory nut. We used discrete choice models to describe selection under conditions of changing choice sets. Blue Jays displayed a clear preference for pin oak and strong avoidance of red oak acorns when alternative foods were available. White oak and black oak acorns were selected intermediately. Shagbark hickory nuts were never used. Correlation coefficients suggested that preference was inversely related to seed size and the proportion of seed consisting of hard seed coat. In the absence of alternative food items, small red oak acorns were readily taken, whereas large red oak acorns were mostly avoided but still used by some birds. These results highlight the importance of considering food availability when making conclusions about preference, and lend support to the hypothesis that Blue Jays can be important dispersers of even less-preferred oak species. We discuss the potential as well as the limitations for Blue Jays to act as seed dispersers, with respect to postglacial range expansion of fagaceous tree species, and in the context of present-day dispersal in regions where forests are highly fragmented.


2013 ◽  
Vol 93 (2) ◽  
pp. 1-22 ◽  
Author(s):  
Dragan Milosevic ◽  
Igor Ziberna ◽  
Stevan Savic

In this paper spring and autumn temperature thresholds of 5?C and 10?C, active air temperature sums and lengths of growing seasons with temperature threshold of 5?C and 10?C were analyzed. The analysis were made for 10 meteorological stations for the period 1961-2011. The dates of occurrence of phenological phases of selected plants (oxeye daisy, beech, apple, winter wheat and maize) has been investigated. It was observed a tendency of earlier appearance of spring phenological phases and later appearance of autumn phenological phases. As a result extension of vegetation periods in the Republic of Slovenia is present. Dates with occurrence of phenological phases of selected plants from 8 phenological stations were connected with the results of the analysis of meteorological parameters from 8 meteorological stations. The highest correlation coefficients were obtained for the temperature parameters (0.8), while the average precipitation quantities, number of days with frost, potential evapotranspiration and water balance showed a low correlation coefficient values with the appearance of phenological phases.


1979 ◽  
Vol 9 (4) ◽  
pp. 489-494 ◽  
Author(s):  
Paul S. Johnson

Weekly events in shoot elongation were observed and measured for 43 black oak (Quercusvelutina Lam.) and 41 white oak (Q. alba L.) sprouts in their second growing season. In addition, total net shoot elongation (i.e., elongation minus current dieback) was measured at the ends of the first four growing seasons. Sprouts originated from stumps with diameters of 0.6 in. (1.5 cm) to 12 in. (30.5 cm). Average net elongation of both species reached a weekly maximum of 0.6 ft (18.3 cm) during the 3rd growth week (May 4–10). Although elongation among individual sprouts was extremely variable, most sprouts of both species flushed two or more times during the 17-week study period. Periods of individual flushes ranged from 1 to 3 weeks and most occurred during the first 13 growth weeks. Based on regression estimates, 2nd-year gross shoot elongation increased with increasing stump diameter up to 6 in. (15.2 cm); above this diameter shoot elongation decreased. Net 4-year elongation of both species also tended to increase with increasing stump diameter up to 6 in. There were no significant differences between species in 2nd-year gross elongation or in total 4-year net elongation.


2019 ◽  
Author(s):  
Kamal Ahmed ◽  
Shamsuddin Shahid ◽  
Xiao-Jun Wang ◽  
Nadeem Nawaz ◽  
Najeebullah Khan

Abstract. The changing characteristics of aridity over a larger spatiotemporal scale have gained interest in recent years due to climate change. The long-term (1901–2016) changes in spatiotemporal patterns of annual and seasonal aridity during two major crop growing seasons of Pakistan, Kharif and Rabi are evaluated in this study using gridded precipitation and potential evapotranspiration (PET) data. UNESCO aridity index was used to estimate aridity at each grid point for all the years between 1901 and 2016. The temporal changes in aridity and its associations with precipitation and PET are evaluated by implementing a moving window of 50-years data with 11-year interval. The modified Mann Kendall trend test is applied to estimate unidirectional change by eliminating the effect of natural variability of climate and the Pettitt’s test is used to detect year of change in aridity. The results reveal that climate over 60 % of Pakistan (mainly in southern parts) is arid. The spatial patterns of aridity trends show a strong influence of the changes in precipitation on aridity trend. The increasing trend in aridity is noticed in the southeast where precipitation is low during Kharif while a decreasing trend in Rabi season in the region which receives high precipitation due to western disturbances. The annual and Kharif aridity are found to decrease at a rate of 0.0001 to 0.0002 per year in northeast while Kharif and Rabi aridity are found to increase at some locations in the south at a rate of −0.0019 to −0.0001. The spatial patterns of aridity changes show a shift from arid to the semi-arid climate in annual and Kharif over a large area while a shift from arid to hyper-arid region during Rabi in a small area. The most of the significant changes in precipitation and aridity are observed in the years between 1971 and 1980. Overall, aridity is found to increase in 0.52 %, 4.44 %, and 0.52 % area and decrease in 11.75 %, 7.57 %, and 9.66 % area for annual, Rabi and Kharif seasons respectively during 1967–2016 relative to 1901–1950.


2019 ◽  
Vol 23 (7) ◽  
pp. 3081-3096 ◽  
Author(s):  
Kamal Ahmed ◽  
Shamsuddin Shahid ◽  
Xiaojun Wang ◽  
Nadeem Nawaz ◽  
Najeebullah Khan

Abstract. The changing characteristics of aridity over a larger spatiotemporal scale have gained interest in recent years due to climate change. The long-term (1901–2016) changes in spatiotemporal patterns of annual and seasonal aridity during two major crop growing seasons of Pakistan, Kharif and Rabi, are evaluated in this study using gridded precipitation and potential evapotranspiration (PET) data. The UNESCO aridity index was used to estimate aridity at each grid point for all the years between 1901 and 2016. The temporal changes in aridity and its associations with precipitation and PET are evaluated by implementing a moving window of 50 years of data with an 11-year interval. The modified Mann–Kendall (MMK) trend test is applied to estimate unidirectional change by eliminating the effect of natural variability of climate, and Pettitt's test is used to detect year of change in aridity. The results revealed that the climate over 60 % of Pakistan (mainly in southern parts) is arid. The spatial patterns of aridity trends show a strong influence of the changes in precipitation on the aridity trend. The increasing trend in aridity (drier) is noticed in the southwest, where precipitation is low during Kharif, while there is a decreasing trend (wetter) in the Rabi season in the region which receives high precipitation due to western disturbances. The annual and Kharif aridity is found to decrease (wetter) at a rate of 0.0001 to 0.0002 per year in the northeast, while Kharif and Rabi aridity are found to increase (drier) at some locations in the south at a rate of −0.0019 to −0.0001 per year. The spatial patterns of aridity changes show a shift from arid to the semi-arid (wetter) climate in annual and Kharif over a large area while showing a shift from arid to hyper-arid (drier) region during Rabi in a small area. Most of the significant changes in precipitation and aridity are observed in the years between 1971 and 1980. Overall, aridity is found to increase (drier) in 0.52 %, 4.44 % and 0.52 % of the area and decrease (wetter) in 11.75 %, 7.57 % and 9.66 % of the area for annual, Rabi and Kharif seasons respectively during 1967–2016 relative to 1901–1950.


1984 ◽  
Vol 64 (4) ◽  
pp. 943-950 ◽  
Author(s):  
J. W. HALL ◽  
W. MAJAK ◽  
R. J. WILLIAMS ◽  
R. E. HOWARTH

Daily weather records from seven consecutive growing seasons and daily nitrogen levels in alfalfa herbage from the last four seasons were studied in order to identify relationships with bloat in cattle. The cattle tended to bloat as a group rather than independently. Bloat occurred on at least 30% of the days observed in each season but in the two driest, warmest years the percentages increased to 46 and 63. Days on which bloat occurred were preceded by lower maximum and minimum temperatures on the average than days on which bloat did not occur but the difference in temperature was small. On a daily basis no differences were observed between days of bloat and no bloat in hours of sunshine, temperature range, precipitation, solar radiation flux or potential evapotranspiration. The concentration of total nitrogen, soluble nitrogen and soluble protein nitrogen in the feed was higher on days when bloat occurred than when it did not occur. Key words: Pasture bloat, alfalfa, cattle, climate, evapotranspiration


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Minjeong Kim ◽  
Ja Young Oh ◽  
Seon Ha Bae ◽  
Seung Hyeun Lee ◽  
Won Jun Lee ◽  
...  

AbstractWe evaluated the reliability and validity of the 5-scale grading system to interpret the point-of-care immunoassay for tear matrix metalloproteinase (MMP)-9. Six observers graded red bands of photographs of the readout window in MMP-9 immunoassay kit (InflammaDry) two times with 2-week interval based on the 5-scale grading system (i.e. grade 0–4). Interobserver and intraobserver reliability were evaluated using intraclass correlation coefficients. The interobserver agreements were analyzed according to the severity of tear MMP-9 expression. To validate the system, a concentration calibration curve was made using MMP-9 solutions with reference concentrations, then the distribution of MMP-9 concentrations was analyzed according to the 5-scale grading system. Both intraobserver and interobserver reliability was excellent. The readout grades were significantly correlated with the quantified colorimetric densities. The interobserver variance of readout grades had no correlation with the severity of the measured densities. The band density continued to increase up to a maximal concentration (i.e. 5000 ng/mL) according to the calibration curve. The difference of grades reflected the change of MMP-9 concentrations sensitively, especially between grade 2 and 4. Together, our data indicate that the subjective 5-scale grading system in the point-of-care MMP-9 immunoassay is an easy and reliable method with acceptable accuracy.


Genetics ◽  
1997 ◽  
Vol 146 (4) ◽  
pp. 1475-1487 ◽  
Author(s):  
S Dumolin-Lapègue ◽  
B Demesure ◽  
S Fineschi ◽  
V Le Come ◽  
R J Petit

Patterns of chloroplast DNA (cpDNA) variation were studied in eight white oak species by sampling 345 populations throughout Europe. The detection of polymorphisms by restriction analysis of PCR-amplified cpDNA fragments allowed the identification of 23 haplotypes that were phylogenetically ordered. A systematic hybridization and introgression between the eight species studied is evident. The levels of subdivision for unordered (G  ST) and ordered (N  ST) alleles are very high and close (0.83 and 0.85). A new statistical approach to the quantitative study of phylogeography is presented, which relies on the coefficients of differentiation G  ST and N  ST and the Mantel's test. Based on pairwise comparisons between populations, the significance of the difference between both coefficients is evaluated at a global and a local scale. The mapped distribution of the haplotypes indicates the probable routes of postglacial recolonization followed by oak populations that had persisted in southern refugia, especially in the Iberian peninsula, Italy and the Balkans. Most cpDNA polymorphisms appear to be anterior to the befinnina of the last recolonization. A subset of the preexisting haplotypes have merely expanded north, while others were left behind in the south.


Author(s):  
Tram T.N. Thai ◽  
Danny G. Le Roy ◽  
Manjula S. Bandara ◽  
James E. Thomas ◽  
Francis J Larney

With soybean [Glycine max (L.) Merr.] seed cost increasing in Alberta, understanding economic optimum plant density (EOPD) could help growers save on input expenses. A study was conducted at two irrigated locations in southern Alberta (Bow Island and Lethbridge), in three growing seasons (2014–16), using two maturity group (MG) 00 soybean genotypes, two row spacings (RS; narrow, 17.5 cm; wide, 35 cm), and three seeding densities (SD; 30, 50 and 80 seeds m-2). Exponential plant density-yield relationships were used to estimate EOPD. The earlier MG 00.4 genotype compensated yield at lower plant density (39 vs. 43 plants m-2) and emergence (74 vs. 80%) than the later MG 00.8 genotype. The EOPD gaps between environments, genotypes, and RS were minimal (from 1–3 plants m-2), resulting in only 1.3–2.0% differences in grain yield (37–56 kg ha-1), and gross revenue at EOPD ($16–24 ha-1). The overall EOPD estimate was 46 plants m-2, regardless of environment, genotype or RS. The study highlighted the difference between agronomic production and profit maximization in choosing an optimum plant density, and the need to establish a seeding density calculator for irrigated soybean in southern Alberta.


2019 ◽  
Vol 67 (3) ◽  
pp. 280-288 ◽  
Author(s):  
Jitka Kofroňová ◽  
Miroslav Tesař ◽  
Václav Šípek

Abstract Longwave radiation, as part of the radiation balance, is one of the factors needed to estimate potential evapotranspiration (PET). Since the longwave radiation balance is rarely measured, many computational methods have been designed. In this study, we report on the difference between the observed longwave radiation balance and modelling results obtained using the two main procedures outlined in FAO24 (relying on the measured sunshine duration) and FAO56 (based on the measured solar radiation) manuals. The performance of these equations was evaluated in the April–October period over eight years at the Liz experimental catchment and grass surface in the Bohemian Forest (Czech Republic). The coefficients of both methods, which describe the influence of cloudiness factor and atmospheric emissivity of the air, were calibrated. The Penman-Monteith method was used to calculate the PET. The use of default coefficient values gave errors of 40–100 mm (FAO56) and 0–20 mm (FAO24) for the seasonal PET estimates (the PET was usually overestimated). Parameter calibration decreased the FAO56 error to less than 20 mm per season (FAO24 remained unaffected by the calibration). The FAO56 approach with calibrated coefficients proved to be more suitable for estimation of the longwave radiation balance.


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