Evolution of argoma shrubland (Ulex gallii Planch.) after clearing and burning treatments in Sierra de Aralar and Belate (Navarra)

Shrub encroachment is considered one of the greatest threats in the conservation of pastures, especially in abandoned territories and territories with low stocking density. However, in the Navarra Pyrenees and Basque mountains, with a high stocking density maintained during the last decades, the expansion of argoma shrubland (Ulex gallii), shows that grazing is not enough for its control and requires evaluating measures of clearing. To evaluate the efficiency of the burning and the mechanical clearing (with two treatments: at ground level and 10 cm above ground) in the control of the shrub, these treatments were applied in different plots of encroached grasslands in two pastoral territories (Sierra de Aralar and Belate). After the burning and clearing, the evolution of the shrub was compared in the cleared plots closed to grazing and in their replicas open to it. The results showed differences between the different treatments in both territories that may be related to the initial coverage of the shrubland. In general, burning was less effective in controlling shrubland and allowed a greater resprout than mechanical clearing. No significant differences were found between the two types of mechanical clearing (at ground level and at 10 cm above ground). Finally, grazing caused a delay in the recovery of the shrub in all casesbut it was not able to eliminate the shrubs completely. From the field observations, the opinions of the farmers and the results of similar experiences, some measures for grassland management were collected and discussed to correct or complement the clearing treatments in order to increase their efficiency.

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Field Observations on Adults of the Wheat Bulb Fly (Leptohylemyia coarctata (Fall.)).

Bulletin of Entomological Research ◽

10.1017/s000748530005344x ◽

1958 ◽

Vol 49 (1) ◽

pp. 77-94 ◽

Cited By ~ 10

Author(s):

D. B. Long

Keyword(s):

Ground Level ◽

Early Morning ◽

Temperature Threshold ◽

Field Observations ◽

Emergence Period ◽

Temperature Rhythm ◽

Population Peak ◽

Late Evening ◽

Number Of Males ◽

Active Return

A study of adult populations of Wheat Bulb Ply, Leptohylemyia coarctata (Fall.), has been carried out in the field by routine sweeping at Rothamsted. It has been observed that the males emerge slightly before the females and that the emergence period may cover at least three weeks in late June and early July. Although the number of males may exceed the number of females at first, the females predominate later in the season due to the shorter life span of the males.The numbers of flies on the wheat have been found to fluctuate appreciably throughout the day. During the first week of the emergence period the number of flies taken increased steadily throughout the day. After the date of population peak, however, the maximum numbers occurred in the crop in the very early morning and the late evening, which suggested a daily flight dispersion followed by a general or localised return of the flies to the crop. Further study of the data showed that the daily temperature rhythm was only partly responsible for this daily flight dispersion, and that there appeared to be an active return flight to the crop in the evening. Generally the males were more active than the females and did not settle so deeply in the crop.The temperature threshold for flight was observed to be 12 to 13°C. Winds up to 8 m.p.h. did not appear to affect flight activity, but higher winds, e.g., 15 m.p.h., markedly reduced flight, the flies remaining deep in the crop near ground level. Gale-force winds, however, were observed to produce a permanent depletion in the number of flies infesting Broadbalk field, indicating that the population was probably localised.Although portions of the populations dispersed fairly rapidly from the emergence sites, recaptures of radioactive flies labelled with 32P indicated that the extent of the dispersions was not very great. The females dispersed more than the males, and were influenced to some extent by the occurrence of wheat in flower. Frequently the flies were found to have congregated on the lee edge of the crop, but other preferred regions have been observed which could not be attributed to the influence of the wind.

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USE OF TRAPS BAITED WITH VIRGIN FEMALES FOR FIELD OBSERVATIONS ON THE BERTHA ARMYWORM (LEPIDOPTERA: NOCTUIDAE)

The Canadian Entomologist ◽

10.4039/ent107781-7 ◽

1975 ◽

Vol 107 (7) ◽

pp. 781-784 ◽

Cited By ~ 9

Author(s):

G. E. Swailes ◽

D. L. Struble ◽

N. D. Holmes

Keyword(s):

Ground Level ◽

Field Observations ◽

Above Ground Level ◽

Lepidoptera Noctuidae ◽

Bertha Armyworm

AbstractCylindrical traps with screen cones at the ends baited with virgin females and placed in rape fields about 1 m above ground level were effective in trapping males of the bertha armyworm. Males were most active between 0330 and 0430 h M.D.T. and moved precisely to confined females. Virgin females became attractive 1 day after emergence and remained attractive for at least 7 days. Trapping was an effective method for rapidly determining the presence of bertha armyworm.

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Settlement of a Furnace Foundation, Sorel, Quebec

Canadian Geotechnical Journal ◽

10.1139/t68-004 ◽

1968 ◽

Vol 5 (1) ◽

pp. 46-56 ◽

Cited By ~ 5

Author(s):

H Q Golder ◽

J C Osler

Keyword(s):

Ground Level ◽

Significant Feature ◽

Field Observations ◽

Overburden Pressure ◽

Total Settlement ◽

Below Ground ◽

Leda Clay ◽

Settlement Analysis

The Smelter of Quebec Iron and Titanium Corporation at St. Joseph de Sorel, Quebec, is located in an area which is underlain by about 80 feet of compact stratified sand, silt, and clay, followed by at least 150 feet of Leda clay. Five furnaces were constructed during 1950–52, and four more furnaces have been added subsequently. Settlement records spanning some fifteen years are available for the original furnaces.Recently, it was decided to replace No. 1 Furnace with a new unit, the weight of which will be slightly more than twice that of the existing furnace. The present furnace is founded on 32 Franki piles of 75 tons capacity; the piles are 22 feet long and are cut off about 5 feet below ground level. As it was desired to incorporate the existing piles in the foundation for the new furnace it was necessary to know whether new piles could be driven and loaded together with the existing piles without causing overstressing of the latter, which had been preloaded by the weight of the existing furnace.A settlement analysis of the existing furnace foundation was undertaken, in which sensible agreement was obtained with the observed settlements. Predictions of the rebound of the existing furnace foundation during demolition were made and these were in approximate agreement with field observations. Finally, an estimate of the settlement which the new furnace will experience was made.A significant feature of the problem is that a large portion of the total settlement experienced to date is due to consolidation of the underlying Leda clay stratum, despite the fact that the furnace foundation areas are small in size compared to the thickness of the overlying granular deposits, thereby inducing only small increases in pressure in relation to the existing overburden pressure.

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Changes in air quality in different phases of forest management process in a sub-mountain beech ecosystem (West Carpathian Mts.)

Journal of Forest Science ◽

10.17221/1/2009-jfs ◽

2009 ◽

Vol 55 (No. 8) ◽

pp. 368-375 ◽

Cited By ~ 2

Author(s):

D. Kellerová

Keyword(s):

Air Quality ◽

Forest Management ◽

Stocking Density ◽

Ground Level ◽

Vegetation Period ◽

Management Process ◽

Ozone Concentrations ◽

Regular Time ◽

The Individual ◽

Proton Load

We studied air quality in a sub-mountain beech ecosystem in the Kremnické vrchy Mts., Central Slovakia. We chose the method of passive sampling. The amounts of airborne pollutants (H+ and O3) were determined at regular time intervals, covering the whole vegetation period, on four plots with different stocking. The original stand was subjected to two cuts with a purpose to simulate the phases of a common silvicultural process. The first research period (1999–2003) started 10 years after the first cutting, the second (2004–2006) was launched immediately after the second cut. Ten years after applying the first cut, the differences in the proton load input were getting smaller – with the dynamically changing crown canopy. The largest difference in proton load (H+ was found between plots C and I after the second intervention, when the correlation coefficient value was 0.15. The differences in proton load input between the plots were influenced by the cut, especially in the first three years after its application. No significant differences in ground level ozone concentrations between plots I (intensive cut), Me (medium intensive), Mo (moderate) and C (control) were revealed either after the first or after the second cutting intervention. Differences in ozone concentrations are not significant, and they indicate that the stocking density does not play an important role in association with ozone affecting the stands. The increase in ozone concentrations after the second intervention was evident on all plots – indicating the absence of connection with the individual phases of forest management process, but at the same time indicating the presence of climate change. In the studied sub-mountain beech ecosystem in the Kremnické vrchy Mts., an important role of episodes with high ozone concentrations is evident.

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Using Google Street View to Examine Urban Context and Green Amenities in the Global South: The Chilean Experience

Frontiers in Sustainable Cities ◽

10.3389/frsc.2021.684231 ◽

2021 ◽

Vol 3 ◽

Author(s):

Mônica Haddad ◽

Zachary Christman ◽

Hamil Pearsall ◽

Melinda Sanchez

Keyword(s):

Building Materials ◽

Ground Level ◽

Global South ◽

Neighborhood Context ◽

Field Observations ◽

Urban Context ◽

Google Street View ◽

Street View ◽

Virtual Field

This study evaluates the use of virtual, human-interpreted, field observations using Google Street View (GSV) to examine the presence of conditions that may be used to analyze green gentrification in the Global South. We propose that green gentrification is characterized by the introduction or improvement of green amenities (such as parks) as well as corresponding changes to the urban context (such as facade materials). While virtual field observations have been used to examine neighborhood context for other applications, this method has not yet been applied to the study of green gentrification, nor in the Global South. Using one urban park located in Talca, Chile, and in three urban parks located in Santiago, Chile, we sought to address the following research questions: (1) How do in situ and virtual field observations compare as methods of evaluating green amenities and urban context? (2) What characteristics of green amenities and urban context must be addressed to investigate green gentrification in the Global South? (3) How do indicators of green amenities and urban context observed via virtual field observations indicate the potential for green gentrification? In order to observe the streetside conditions of the neighborhoods surrounding established, improved, and new parks, we utilize the ground-level 360° imagery through GSV as an alternative to in situ studies, which can be time-consuming, expensive, and logistically challenging. Features related to the land use composition, building materials used, and the presence of aesthetic improvements and pedestrian amenities were noted as potential indicators of gentrification, and the correspondence between the two methods of observation were evaluated. Results indicate that virtual field observations can provide a promising method that may facilitate the identification and investigation of the effects of green gentrification in the Global South, broadening the scope and application of this research. This comparison offers insight into the use and comparison of virtual and in situ observations for identifying green gentrification in the Global South and for the applicability of the virtual observation method in this heterogeneous urban landscape, especially in cases with unreliable or unavailable data.

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Effects of Vibration on the Preparation of Ultrathin Sections

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010007223x ◽

1973 ◽

Vol 31 ◽

pp. 358-359

Author(s):

Joseph M. Blum ◽

Edward P. Gargiulo ◽

J. R. Sawers

Keyword(s):

Cutting Speed ◽

Ground Level ◽

Environmental Vibration ◽

Block Face ◽

Ultrathin Sections ◽

Embedding Medium ◽

Thickness Variations ◽

Building Walls ◽

Cutting Direction ◽

Diamond Knife

It is now well-known that chatter (Figure 1) is caused by vibration between the microtome arm and the diamond knife. It is usually observed as a cyclical variation in “optical” density of an electron micrograph due to sample thickness variations perpendicular to the cutting direction. This vibration might be induced by using too large a block face, too large a clearance angle, excessive cutting speed, non-uniform embedding medium or microtome vibration. Another prominent cause is environmental vibration caused by inadequate building construction. Microtomes should be installed on firm, solid floors. The best floors are thick, ground-level concrete pads poured over a sand bed and isolated from the building walls. Even when these precautions are followed, we recommend an additional isolation pad placed on the top of a sturdy table.

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