On the Relative Abundance of Some Australian Psyllidae That Coexist on Eucalyptus Blakelyi.

1974 ◽  
Vol 22 (3) ◽  
pp. 387 ◽  
Author(s):  
LR Clark ◽  
MJ Dallwitz
Keyword(s):  
Soil Moisture ◽  
Host Plant ◽  
Relative Abundance ◽  
Fruit Production ◽  
Australian Capital Territory ◽  
Australian Capital ◽  
Air Temperatures ◽  
Extent Of Damage ◽  
Moisture Conditions ◽  
Autumn And Winter

A 7-year study of fluctuations in the numbers of four psyllids, Glycaspis spp. (G. brimblecombei and G. prepta combined), Spondyliaspis sp. and Creiis costatus, on mature E. blakelyi in the woodlands of the Australian Capital Territory suggests that: (I) The favourableness of the leaves of the host plant as a source of food was the principal environ- mental influence affecting the abundance of each kind of psyllid; (2) Favourableness was determined by the depIetion and aging of leaves involved in the host plant's 2-year cycle of reproduction and foliage replacement (notably, as affected by the extent of fruit production), and, to differing degrees for the different kinds of psyllid, by the extent of damage caused by leaf-eating beetles, previous and prevailing soil moisture conditions (as estimated by a model using rainfall and evaporation as input), and possibly air temperatures in autumn and winter ; (3) The resulting variation in the favourableness of leaves was responsible for similarities in the fluctuations of abundance recorded for the psyllids; and (4) Those characteristics of the psyllids which defined their food requirements and ability to obtain food were responsible for differences in their abundance, mainly in the amplitude of fluctuations.

Distribution and habitat preference of the broad-toothed rat (Mastacomys fuscus) in the Australian Capital Territory, Australia

2015 ◽  
Vol 37 (2) ◽  
pp. 125 ◽  
Author(s):  
Richard N. C. Milner ◽  
Danswell Starrs ◽  
Greg Hayes ◽  
Murray C. Evans
Keyword(s):  
Climate Change ◽  
Relative Abundance ◽  
Field Survey ◽  
Habitat Preferences ◽  
Vegetation Types ◽  
Australian Capital Territory ◽  
Australian Capital ◽  
Eastern Australia ◽  
Tussock Grassland ◽  
Feral Animals

The broad-toothed rat (Mastacomys fuscus) is a small to medium-sized rodent found in south-eastern Australia. Recent surveys across the southern portion of its range indicate that the species is in decline, and climate change has been identified as a key threat to the localised persistence of this species. The present study reports on a rapid field survey across 14 high montane and subalpine sites (including moist tussock grassland, sedgelands, heathlands and bogs) in the southern Australian Capital Territory, Australia. M. fuscus scats were recorded along transects, and habitat, vegetation, distance to drainage lines and disturbance due to feral animals were recorded. Relative abundance of M. fuscus was positively related to specific vegetation types (heath, sedge and Poa) and site size. Conversely, relative abundance of M. fuscus was negatively related to disturbance due to feral animals, and distance from creek drainage lines. This study indicates that M. fuscus has specific habitat preferences and threats associated with environmental change and introduced species may threaten populations in the Australian Capital Territory.

scholarly journals Hydrometeorological conditions preceding wildfire, and the subsequent burning of a fen watershed in Fort McMurray, Alberta, Canada

2017 ◽  
Author(s):  
Matthew C. Elmes ◽  
Dan K. Thompson ◽  
James H. Sherwood ◽  
Jon S. Price
Keyword(s):  
Soil Moisture ◽  
Management Strategies ◽  
Organic Soil ◽  
Spring Precipitation ◽  
Air Temperatures ◽  
Dry Conditions ◽  
Lowland Forests ◽  
Moisture Conditions ◽  
High Elevations ◽  
Hydrometeorological Conditions

Abstract. The destructive nature of the ~ 590,000 ha Horse River Wildfire in the Western Boreal Plain (WBP), northern Alberta in May of 2016 motivated the investigation of the hydrometeorological conditions that preceded the fire. Historical climate and field hydrometeorological data from a moderate-rich fen watershed were used to identify a) whether the spring 2016 conditions were outside the range of natural variability for WBP climate cycles; b) explain the observed patterns in burn severity across the watershed; and c) identify whether fall and winter moisture signals observed in peatlands and lowland forests in the region are indicative of fire susceptibility. Field hydrometeorological data from the fen watershed confirmed the presence of cumulative moisture deficits prior to the fire. Hydrogeological investigations highlighted the susceptibility of fen and upland areas to water table and soil moisture decline over rain-free periods (including winter), due to the watershed's reliance on supply from localized flow systems originating in topographic highs. Subtle changes in topographic position led to large changes in groundwater connectivity, leading to greater organic soil consumption in wetland margins and at high elevations. The 2016 spring moisture conditions measured prior to the ignition of the fen watershed were not illustrated well by the Drought Code (DC) when standard overwintering procedures were applied. However, close agreement was found when default assumptions were replaced with measured duff soil moisture recharge and incorporated into the overwintering DC procedure. We conclude that accumulated moisture deficits dating back to the summer of 2015 led to the dry conditions that preceded the fire. The infrequent coinciding of several hydrometeorological conditions, including low autumn soil moisture, a modest snowpack, lack of spring precipitation, and high spring air temperatures and winds, ultimately led to the Horse River wildfire spreading widely and causing observed burn patterns. Monitoring soil moisture at different land classes and watersheds would aid management strategies in the production of more accurate overwintered DC calculations, providing fire management agencies early warning signals ahead of severe spring wildfire seasons.

The Status and Distribution of The Platypus (Ornithorhynchus anatinus) In the Australian Capital Territory with Notes on Some Localised Declines.

1998 ◽  
Vol 20 (2) ◽  
pp. 306
Author(s):  
M. Linternmans
Keyword(s):  
Relative Abundance ◽  
Ad Hoc ◽  
Australian Capital Territory ◽  
River Systems ◽  
The Public ◽  
Australian Capital ◽  
The Past ◽  
Ornithorhynchus Anatinus ◽  
Service Staff ◽  
The Status

Incidental captures of platypuses have been recorded during fisheries research programs conducted in the Australian Capital Territory over the past 25 years. Ad hoc records have also been recorded from Australian Capital Territory Parks and Conservation Service staff and members of the public as part of an ongoing database project known as the ACT Vertebrate Atlas. Information is presented on the distribution and relative abundance of platypuses in the major ACT streams. There appear to have been some localised declines in a number of ACT platypus populations in the Murrumbidgee, Molonglo and Queanbeyan River systems. Possible reasons behind these declines are discussed.

scholarly journals Hydrometeorological conditions preceding wildfire, and the subsequent burning of a fen watershed in Fort McMurray, Alberta, Canada

2018 ◽  
Vol 18 (1) ◽  
pp. 157-170 ◽  
Author(s):  
Matthew C. Elmes ◽  
Dan K. Thompson ◽  
James H. Sherwood ◽  
Jonathan S. Price
Keyword(s):  
Soil Moisture ◽  
Management Strategies ◽  
Organic Soil ◽  
Spring Precipitation ◽  
Air Temperatures ◽  
Dry Conditions ◽  
Lowland Forests ◽  
Moisture Conditions ◽  
High Elevations ◽  
Hydrometeorological Conditions

Abstract. The destructive nature of the  ∼  590 000 ha Horse river wildfire in the Western Boreal Plain (WBP), northern Alberta, in May of 2016 motivated the investigation of the hydrometeorological conditions that preceded the fire. Historical climate and field hydrometeorological data from a moderate-rich fen watershed were used to (a) identify whether the spring 2016 conditions were outside the range of natural variability for WBP climate cycles, (b) explain the observed patterns in burn severity across the watershed, and (c) identify whether fall and winter moisture signals observed in peatlands and lowland forests in the region are indicative of wildfire. Field hydrometeorological data from the fen watershed confirmed the presence of cumulative moisture deficits prior to the fire. Hydrogeological investigations highlighted the susceptibility of fen and upland areas to water table and soil moisture decline over rain-free periods (including winter), due to the watershed's reliance on supply from localized flow systems originating in topographic highs. Subtle changes in topographic position led to large changes in groundwater connectivity, leading to greater organic soil consumption by fire in wetland margins and at high elevations. The 2016 spring moisture conditions measured prior to the ignition of the fen watershed were not illustrated well by the Drought Code (DC) when standard overwintering procedures were applied. However, close agreement was found when default assumptions were replaced with measured duff soil moisture recharge and incorporated into the overwintering DC procedure. We conclude that accumulated moisture deficits dating back to the summer of 2015 led to the dry conditions that preceded the fire. The infrequent coinciding of several hydrometeorological conditions, including low autumn soil moisture, a modest snowpack, lack of spring precipitation, and high spring air temperatures and winds, ultimately led to the Horse river wildfire spreading widely and causing the observed burn patterns. Monitoring soil moisture at different land classes and watersheds would aid management strategies in the production of more accurate overwintered DC calculations, providing fire management agencies early warning signals ahead of severe spring wildfire seasons.

scholarly journals THE INFLUENCE OF SOIL MOISTURE, NITROGEN FERTILIZATION, AND TEMPERATURE ON QUALITY AND AMINO ACID COMPOSITION OF THATCHER WHEAT

1963 ◽  
Vol 43 (2) ◽  
pp. 219-228 ◽  
Author(s):  
F. W. Sosulski ◽  
E. A. Paul ◽  
W. L. Hutcheon
Keyword(s):  
Amino Acids ◽  
Soil Moisture ◽  
Protein Content ◽  
Nitrogen Fertilization ◽  
Mixing Time ◽  
Grain Protein Content ◽  
Relative Distribution ◽  
Air Temperatures ◽  
Moisture Conditions ◽  
Sedimentation Value

The protein content of Thatcher wheat grown in the growth chamber was increased by reduced water supply, nitrogen fertilization, and higher air temperatures. Soil moisture conditions had a greater influence on protein content at higher temperatures, while the largest responses to nitrogen fertilization were obtained at the medium moisture level. Changes in sedimentation value and mixing time were associated with protein content except for plants grown at 62°F. Apparently the low temperature had an adverse effect on gluten quality.The relative distribution of 9 amino acids was significantly correlated with changes in grain protein content. Only 6 amino acids gave similar high correlations with flour protein content and sedimentation value. These differences are explained on the basis of changes in the morphology of the wheat grain and the proportion of flour proteins.

An importance of soil humidification in forming of avifauna of arboreal plantation in the Biosphere reserve «Askania Nova» (un-reproductive period)

2016 ◽  
Vol 27 (3-4) ◽  
pp. 55-69
Author(s):  
M. A. Listopadsky
Keyword(s):  
Soil Moisture ◽  
Influence Factors ◽  
Data Communication ◽  
Biosphere Reserve ◽  
Reproductive Period ◽  
Defined Contribution ◽  
Separate Species ◽  
Steppe Birds ◽  
Reserve Forest ◽  
Autumn And Winter

With gradient analysis investigated the role of soil moisture in the formation of the modern population of birds in the reserve forest plantations. Soil moisture was divided into seven grades. For this purpose used grass cover and the coefficient of local moistening. His proposed PhD L. P. Travleev. This method allows knowing the degree of influence of soil moisture at the birds. We analyzed birds species composition, population, placement in space and power of influence factors (soil moisture). Investigations were carried out on the territory of the Biosphere Reserve «Askania Nova». We studied the birds which live in the reserve at the end of the summer, autumn and winter. This happened from 2006 to 2013 years. Specially was studied as permanently specific form of birds is found in a particular humidity. The degree of coupling was studied using the amount of information that transmits to the local bird humidification. For 68 species of birds are the options of the population density, coefficient koligatsii and data communication with the seven variants of soil moisture. For all kinds of set information «price» of each option dampening that contributes to the formation of a particular community of birds. Thus, the defined contribution to the formation of soil moisture forest bird communities. Species representation and density gradient within the test moisture is not in direct linear relationship from moisture and ranges from 11 (very coldly) to 50 species (moist soil). The density of the community varies from 0,5 birds / hectare (very dry) to 269 birds / hectare (fresh soil). The strongest link between the information and the formation of moisture gradient structure avifauna is typical in a fresh soil – bird on the edge, and wet – forest representatives. These types of humidification function is performed starting in the formation of two major blocks dendrophilous community. The steppe birds give way to forest representatives when the soil slightly moist. The main conclusion of our study includes the following: than wetter the soil the more species of birds lives in the forest; some graduation humidity are the most important for separate species of birds; it is very important for birds, there are places where one can drink water. Further invasive alien species can occur where the soil is moist. Forest with dry soil is already fully occupied by birds.

Evaluation of Presswheels and Seed Coverers for Direct Seeding of Brassica

HortScience ◽  
1997 ◽  
Vol 32 (4) ◽  
pp. 599E-600
Author(s):  
Regina P. Bracy ◽  
Richard L. Parish
Keyword(s):  
Soil Moisture ◽  
Sandy Loam ◽  
Visual Observation ◽  
Mustard Seed ◽  
High Soil Moisture ◽  
Loam Soil ◽  
Direct Seeded ◽  
Plant Emergence ◽  
Moisture Conditions ◽  
Determine Effect

Improved stand establishment of direct-seeded crops has usually involved seed treatment and/or seed covers. Planters have been evaluated for seed/plant spacing uniformity, singulation, furrow openers, and presswheel design; however, effects of presswheels and seed coverers on plant establishment have not been widely investigated. Five experiments were conducted in a fine sandy loam soil to determine effect of presswheels and seed coverers on emergence of direct-seeded cabbage and mustard. Seed were planted with Stanhay 870 seeder equipped with one of four presswheels and seed coverers. Presswheels included smooth, mesh, concave split, and flat split types. Seed coverers included standard drag, light drag, paired knives, and no coverer. Soil moisture at planting ranged from 8% to 19% in the top 5 cm of bed. Differences in plant counts taken 2 weeks after planting were minimal with any presswheel or seed coverer. Visual observation indicated the seed furrow was more completely closed with the knife coverer in high soil moisture conditions. All tests received at least 14 mm of precipitation within 6 days from planting, which may account for lack of differences in plant emergence.

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