Tamarisk (Tamarixspp.) Establishment in its Most Northern Range

2011 ◽  
Vol 4 (1) ◽  
pp. 58-65 ◽  
Author(s):  
Erik A. Lehnhoff ◽  
Fabian D. Menalled ◽  
Lisa J. Rew
Keyword(s):  
Great Plains ◽  
Storage Time ◽  
Storage Period ◽  
Water Levels ◽  
Regulated River ◽  
Northern Great Plains ◽  
Riparian Areas ◽  
Greenhouse Study ◽  
The Relationship ◽  
Hydrologic Conditions

AbstractTamarisk, a shrub or small tree native to Eurasia, was introduced to North America in the early 1800s and is now naturalized throughout many riparian areas of the southwestern United States, where extensive research has been conducted. It is a more recent invader to the northern Great Plains, and fewer studies have been conducted on tamarisk ecology and management in this area. The objectives of this research were to investigate the overwintering potential of tamarisk seeds in Montana and the relationship between hydrologic conditions and historic tamarisk establishment. Emergence of seedlings from seeds stored for different time periods at a range of temperatures was evaluated in a greenhouse study. Emergence rates declined after a 7-d storage period, but storage time had no effect on subsequent emergence rates, and seeds stored at −14 C and 5 C had greater emergence rates than those stored at 20 C and 35 C. Patterns in tamarisk establishment were assessed through age and hydrologic data collected from a reservoir (Fort Peck), a regulated river (Bighorn), and an unregulated river (Yellowstone) in Montana. These data indicated that tamarisk establishment at the reservoir was closely related to historic water levels, whereas establishment on rivers was not related to flow. However, data from the rivers indicated that recruitment differed between regulated and unregulated rivers, with the regulated river having less recruitment after the period of initial colonization than the unregulated river. Our results show that tamarisk seeds have the ability to overwinter in Montana and can establish under a range of flow conditions, indicating potential recolonization of sites after tamarisk removal.

scholarly journals Chlorophyll as an indicator of green tea quality

2014 ◽  
Vol 83 (10) ◽  
pp. S103-S109 ◽  
Author(s):  
Martina Ošťádalová ◽  
Bohuslava Tremlová ◽  
Jana Pokorná ◽  
Martin Král
Keyword(s):  
Chlorophyll Content ◽  
Green Tea ◽  
Storage Time ◽  
Chlorophyll Concentration ◽  
Storage Period ◽  
Storage Conditions ◽  
Qualitative Variable ◽  
Chlorophyll Contents ◽  
Tea Quality ◽  
The Relationship

The objective of this work was to study the changes in chlorophyll contents in green teas stored under different conditions and to suggest the most suitable way and length of green tea storage. A secondary aim was to evaluate the possibility of using the chlorophyll content as an indicator of tea freshness. Samples for analysis were obtained from a range of tea-growing regions. Chlorophyll contents were measured using UV-vis spectrophotometry. Chlorophyll absorbance was measured at 642.5 and 660 nm. Prior to storage, chlorophyll concentration in teas ranged from 1.12 to 1.89 mg per 1 g of tea, which corresponded to data given by other authors. Storage was found to lead to a decline in chlorophyll concentration. From the 6th month of storage onwards, a significant decrease (P < 0.05) was observed in all samples, irrespective of storage conditions. Based on the findings of this study, original and metal packaging can be considered the most chlorophyll-friendly. On the other hand, glass and paper packaging stored in direct daylight were found to have the strongest impact on chlorophyll concentration. Overall, it can be concluded that the storage time can have a strong influence on oolong green tea colour as an important qualitative variable. Thus, the shelf-life of tea should be shorter than the 12 months claimed by most manufacturers. Once the relationship between changes in chlorophyll concentration and length of the storage period had been established, the chlorophyll content was suggested as an indicator of the storage time (freshness) of a tea substance.

scholarly journals Relationship between Winter/Spring Snowfall and Summer Precipitation in the Northern Great Plains of North America

2009 ◽  
Vol 10 (5) ◽  
pp. 1203-1217 ◽  
Author(s):  
Steven M. Quiring ◽  
Daria B. Kluver
Keyword(s):  
Great Plains ◽  
Standardized Precipitation Index ◽  
Summer Precipitation ◽  
Northern Great Plains ◽  
Study Region ◽  
Temperature And Precipitation ◽  
Air Temperatures ◽  
Moisture Conditions ◽  
The Relationship ◽  
Preceding Winter

Abstract On the basis of snowfall observations from 1929 to 1999, positive (negative) snowfall anomalies are associated with wetter (drier) than normal conditions during the summer [July–August (JJA)] in the northern Great Plains. The five driest summers are associated with negative snowfall anomalies during the preceding winter (−66.7 mm) and spring (−62.4 mm) that cover most of the study region (∼85%). Snowfall anomalies during the late spring (April–May) are more important for determining summer moisture conditions than snowfall anomalies in fall [September–November (SON)] or winter [December–February (DJF)]. The link between snowfall anomalies and summer moisture conditions appears to be, at least partly, through soil moisture since positive (negative) snowfall anomalies are associated with wetter (drier) soils, a later (earlier) date of snowmelt, cooler (warmer) air temperatures, and more (less) evaporation during spring and summer. However, the relationship between spring snowfall and summer moisture conditions is only statistically significant when the moisture anomaly index (Z), which accounts for both temperature and precipitation, is used to characterize summer moisture conditions and the signal is weak when just considering precipitation (e.g., standardized precipitation index). Results also indicate that the strength of the relationship between winter/spring snowfall and summer moisture varies significantly over space and time, which limits its utility for seasonal forecasting.

RELATIONSHIP OF CHLOROGENIC ACID CONCENTRATION IN SUNFLOWER ACHENES TO BIRD PREDATION OF SUNFLOWER

1986 ◽  
Vol 66 (1) ◽  
pp. 11-17 ◽  
Author(s):  
D. E. PARFITT ◽  
G. J. FOX ◽  
J. D. BROSZ
Keyword(s):  
Chlorogenic Acid ◽  
Great Plains ◽  
Passer Domesticus ◽  
Northern Great Plains ◽  
Bird Predation ◽  
Xanthocephalus Xanthocephalus ◽  
Helianthus Annus ◽  
Bird Damage ◽  
Relationship Of ◽  
The Relationship

Blackbird feeding on sunflower is a significant problem in parts of the Northern Great Plains. Therefore, experiments were initiated to determine the relationship of chlorogenic acid (CA) in sunflower achenes to bird predation and the amount of variability for CA in sunflower genotypes. Eight inbred sunflower (Helianthus annuus L.) genotypes with variable levels of resistance to blackbird (Agelaius phoeniceus L. and Xanthocephalus xanthocephalus Bonaparte) and house sparrow (Passer domesticus L.) predation were evaluated at two locations in 1979 and 1980 for seed and hull CA. Differences were observed among inbred sunflower genotypes for CA concentration in both hull and seed. However, no significant correlation between percent CA in seed and mean percent bird damage over the four tested environments was observed. An unexpected positive correlation for hull CA and bird damage was found, however. Achene samples were taken from three positions within the sunflower head (outside, middle and inside) from seven inbred lines at three sampling dates. Genotype influenced CA level in both achene components while sampling date influenced CA level in the seed only. Position of achenes within the sunflower head did not influence CA concentration of either hull or seed. Thus, it is unlikely that the CA concentration of physiologically mature sunflower achenes (hull or seed) causes the observed bird predation pattern (edge to center) on sunflower heads. CA concentration is not apparently related to bird damage.Key words: Sunflower, bird feeding, chlorogenic acid, Helianthus annus L., blackbird

scholarly journals Paleohydrology, Sedimentology, and Geochemistry of Two Meromictic Saline Lakes in Southern Saskatchewan

2007 ◽  
Vol 40 (1) ◽  
pp. 5-15 ◽  
Author(s):  
William M. Last ◽  
Laurie A. Slezak
Keyword(s):  
Great Plains ◽  
Saline Lakes ◽  
Sediment Cores ◽  
Water Levels ◽  
Northern Great Plains ◽  
Climatic Fluctuations ◽  
South Central ◽  
Basin Morphology ◽  
Organic Productivity ◽  
Inorganic Carbonate

ABSTRACT The Northern Great Plains of western Canada contain numerous saline and hypersaline lakes. Most of these lakes are shallow (< 3 m) and exhibit playa characteristics. Some, however, are relatively deep, permanent water bodies. The sediment records of these deep perennial saline lakes offer an excellent opportunity to evaluate key paleohydrologic and hydrochemical parameters. Variations in these parameters may, in turn, be interpreted with respect to climatic fluctuations in the region. Waldsea and Deadmoose lakes, located in south-central Saskatchewan, are both presently meromictic, with saline Mg-Na-SO4-CI waters overlying denser hypersaline brines of similar composition. The modern sediments of the lakes consist of a mixture of organic matter, finegrained detrital elastics (mainly clay minerals, carbonate minerals, quartz, and feldspars), and finely crystalline endogenic/authigenic precipitates (aragonite, gypsum, calcite, pyrite, and mirabilite). Variations in mineralogy and chemistry of sediment cores from the morphologically simple Waldsea basin show that the lake was much shallower and more saline about 4000 years ago. Although water levels have since generally increased in the basin giving rise to higher organic productivity and greater inorganic carbonate precipitation, there is also evidence of several hydrologie reversals during the last 2000 years. The stratigraphy preserved in nearby Deadmoose Lake is much more complex because of the irregular basin morphology. Lower water levels about 1000 years ago created several isolated but still relatively deep lakes in the Deadmoose basin.

The Sterility of Reusable Surgical Instruments with Pouches Packaging on One of the Private Hospital in Bandung

2017 ◽  
Vol 8 (2) ◽  
Author(s):  
Kurniawansyah I. S. ◽  
Mita S. R. ◽  
Najla E. ◽  
Nindayani E.
Keyword(s):  
Storage Time ◽  
Private Hospital ◽  
Surgical Instruments ◽  
Healthcare Associated Infection ◽  
Sterility Testing ◽  
Reusable Instruments ◽  
Healthcare Associated ◽  
The Relationship ◽  
Common Infection ◽  
Long Storage

Healthcare associated infection is one of the common infection that happens in Indonesia. One form control to prevent healthcare associated infection is the sterilization process of the materials and medical instruments that used for taking care of patients. At the private hospital whereas a place of research, there’s never been done the study of sterility test for reusable instrument with pouches, based on previous studies showed that 8 sets from 40 sets of reusable instrument with linen were not sterile moreover there were positively influence from the amount of time to the sterility of reusable instrument. The purpose of these studies was to determining the relationship between a long storage time and the sterility of reusable instruments with pouches. The method that used in this study was the sterility testing of reusable instrument with pouches which were stored in a central operations room storage with a long storage time of 1 and 2 months. From 30 reusable instruments with pouches which were stored for nine months there were 5 instruments were not sterile. The results of statistic analysis showed that the amount of storage time not significantly associated to the sterility of reusable instrument with pouches in the operating room central storage space.

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