How endemic injuries affect early growth of aspen suckers

1984 ◽  
Vol 14 (6) ◽  
pp. 755-762 ◽  
Author(s):  
Donald A. Perala
Keyword(s):  
Tree Mortality ◽  
Stocking Density ◽  
Early Growth ◽  
Site Quality ◽  
Tree Class ◽  
High Incidence ◽  
Good Site ◽  
Negative Effect ◽  
Controlled Experimentation ◽  
Stem Position

The number and stem position of three endemic disease- and insect-caused injuries, shoot dieback, galls, and lesions, were monitored during the first 7 years of development of aspen (Populustremuloides Michx.) sucker stands on both a good and an excellent site. Injury frequency was significantly higher on the good site compared with the excellent site. Only shoot dieback clearly had a negative effect on height growth and tree class differentiation. Galls and lesions were related directly to bole area but not tree class. These injuries healed rapidly and most were undetectable within a few years. The apparently high incidence of insect- and disease-induced injury is normal in aspen sucker stands. Tree mortality was caused by intraspecific suppression and was not enhanced by any of these injuries. Although growth is undoubtedly diminished owing to injury, productivity of these stands should meet or exceed historical expectations. The effect of site quality, stocking density, and other stand variables on the influence of insect- and disease-induced injury needs controlled experimentation to assess their roles in affecting aspen productivity.

scholarly journals Immediate rehabilitation with feeding appliance of a three day old neonate with cleft lip and palate- a case report

2017 ◽  
Vol 13 (2) ◽  
pp. 293-295
Author(s):  
Deepika Kapoor ◽  
Deepanshu Garg
Keyword(s):  
Case Report ◽  
Cleft Lip ◽  
Multidisciplinary Approach ◽  
Cleft Lip And Palate ◽  
Facial Growth ◽  
Orofacial Clefts ◽  
High Incidence ◽  
Negative Effect ◽  
Growth Development ◽  
Very High

Orofacial clefts (OFC) are one of the most common congenital problems seen with a very high incidence. It imparts a negative effect on the overall health of the child by hindering in his feeding practices, normal facial growth, development of dentition and hence speech. Infants born with orofacial clefts have oronasal communication which creates a problem with the creation of negative pressure inside the oral cavity required for suckling.The treatment for such patients is with the multidisciplinary approach but the preliminary  concern for the neonate is to help with the feeding for which a feeding appliance is given. This case report presents a case of a 3-day old infant to whom a feeding appliance was given to aid in suckling. 

scholarly journals THE VULNERABILITY OF BALSAM FIR TO SPRUCE BUDWORM ATTACK IN NORTHWESTERN ONTARIO, WITH SPECIAL REFERENCE TO THE PHYSIOLOGICAL AGE OF THE TREE

1958 ◽  
Vol 34 (4) ◽  
pp. 405-422 ◽  
Author(s):  
J. R. Blais
Keyword(s):  
Special Reference ◽  
Tree Mortality ◽  
Spruce Budworm ◽  
Balsam Fir ◽  
Site Quality ◽  
Physiological Age ◽  
Northwestern Ontario ◽  
Relationship Of ◽  
The Relationship ◽  
Relative Vulnerability

The annual defoliation by spruce budworm and the progressive mortality of balsam fir trees were recorded in nine study plots in northwestern Ontario over a period of 11 years. In addition to general observations on the relationship of tree mortality to defoliation, some information was obtained on the relative vulnerability of the trees with respect to size, physiological age (flowering condition), and vigor (site quality).

Effects of aspect and type of competition on the early performance of Nothofagus dombeyi and Nothofagus nervosa in a mixed plantation

2011 ◽  
Vol 41 (5) ◽  
pp. 1075-1081 ◽  
Author(s):  
Pablo J. Donoso ◽  
Ariel A. Muñoz ◽  
Oscar Thiers ◽  
Daniel P. Soto ◽  
Claudio Donoso
Keyword(s):  
The North ◽  
The Andes ◽  
Mixed Plantations ◽  
Good Site ◽  
Negative Effect ◽  
Mixed Plantation ◽  
Early Performance ◽  
Nothofagus Dombeyi ◽  
Nothofagus Nervosa ◽  
Ecological Differences

In the Andes of Chile, two valuable Nothofagus tree species coexist (Nothofagus dombeyi (Mirb.) Oerst. and Nothofagus nervosa (Phil.) Krasser). They could provide an opportunity for mixed plantations because of their ecological differences. In a mixed plantation with a checkerboard design on a good site where the two species naturally coexist, we evaluated their performance according to aspect and type of competition. Nothofagus dombeyi had a greater survivorship (90% vs. 65%) and growth (twice in diameter and 20% greater in height). Forking was significantly lower in N. nervosa (23% vs. 70%). Aspect did not significantly affect the performance of N. dombeyi. The north aspect had a significant negative effect on survivorship of N. nervosa, but aspect did not significantly affect growth or forking of this species. The aspect – type of competition interaction was only significant for N. nervosa in diameter and marginally significant in height. The checkerboard design allowed for a clear separation of interspecific and intraspecific competition in this mixed plantation. Interspecific competition favored growth of N. nervosa on the north aspect (facilitation) and was detrimental to N. nervosa on the south aspect (competition). These results have a direct application when planting mixtures of species of complementary ecological characteristics that can increase the value of the plantation.

La photographie aérienne couleur infrarouge à petite échelle et l'inventaire des dégâts causés par la tordeuse des bourgeons de l'épinette

1976 ◽  
Vol 52 (3) ◽  
pp. 137-142
Author(s):  
J. Beaubien
Keyword(s):  
High Altitude ◽  
Tree Mortality ◽  
Choristoneura Fumiferana ◽  
Aerial Photographs ◽  
Site Quality ◽  
Insect Damage ◽  
Forest Insect ◽  
Color Film ◽  
Almost All ◽  
Stand Characteristics

Since 1970 northeastern North America has experienced a spruce budworm (Choristoneura fumiferana (Clem.)) outbreak. In Quebec, at the end of 1974, some tree mortality was reported for an area of approximately 3 million acres (1,200,000 ha) of pulpwood stands while severe defoliation occurred over 33 million acres (13,300,000 ha). In an effort to improve current methods used to estimate the extent of forest insect damage over large areas, a remote sensing study was initiated with high altitude color-IR aerial photographs (scale 1:60,000) taken over the Gaspé peninsula in mid-August 1974. Cumulative past feeding was apparent at this period of the summer, as almost all current year chipped needles had fallen. Only very severe damage of one year feeding or more could be identified on the images. Colour variations due to stand characteristics such as density, age, rate of growth, prevent the detection of lighter damage on high-altitude CIR photographs. The relative importance of these factors is discussed. For instance a moderately defoliated dense stand can easily be confused with a more open healthy one. It seems that the two main stand characteristics affecting color tonality are density and length of annual shoot growth which is mainly function of age and site quality. Forest insect damage has been more successfully detected on large (up to 1:2,000) or medium (1:4,000-1:12,000) photo-scales. Normal color film may give better information on defoliation levels. As long as objectives are met, the smallest possible photo scale should be used since cost is reduced because fewer photographs have to be purchased and handled during photo-interpretation work.

scholarly journals Invasion of Winter Moth in New England: Effects of Defoliation and Site Quality on Tree Mortality

Forests ◽  
2014 ◽  
Vol 5 (10) ◽  
pp. 2440-2463 ◽  
Author(s):  
Michael Simmons ◽  
Thomas Lee ◽  
Mark Ducey ◽  
Kevin Dodds
Keyword(s):  
New England ◽  
Tree Mortality ◽  
Site Quality ◽  
Winter Moth

scholarly journals Nile tilapia fingerling cultivated in a low-salinity biofloc system at different stocking densities

2019 ◽  
Vol 16 (4) ◽  
pp. e0612 ◽  
Author(s):  
Priscilla C. M. Lima ◽  
Jéssika L. Abreu ◽  
Allyne E. M. Silva ◽  
William Severi ◽  
Alfredo O. Galvez ◽  
...  
Keyword(s):  
Water Quality ◽  
Water Consumption ◽  
Nile Tilapia ◽  
Stocking Density ◽  
Experimental Period ◽  
Low Salinity ◽  
Final Weight ◽  
Negative Effect ◽  
Black Plastic ◽  
Formulated Feed

A 42-day trial was conducted to evaluate the effects of a low-salinity biofloc system with different stocking densities on water quality and zootechnical performance of Nile tilapia fingerlings (10 g/L). Four treatments were tested at different densities: 500 fish/m³, 750 fish/m³, 1,000 fish/m³ and 1,250 fish/m³, all in triplicate. Fingerlings of Oreochromis niloticus (initial mean weight of 1.17 ± 0.05 g) were stocked in twelve experimental black-plastic tanks (40 L) with no water exchange during the experimental period. Molasses was added daily to the system at 30% of the amount of feed, and fish were given four daily rations of a formulated feed composed of 36% crude protein and 9% lipids. Water quality variables (dissolved oxygen, pH, salinity, TAN, NO2, NO3 and PO43) did not demonstrate significant differences between the treatments. However, significant influences (α ≤ 0.05) of the stocking densities were observed for total suspended solids, settleable solids, final weight, yield, and protein efficiency ratio. The results showed survival over 96%, final weight values between 12 and 18 g, yield between 9.49 and 15.27 kg/m3, water consumption of 52 to 101 L/kg fish, and total time of settling chambers between 238 and 305 h/kg fish. These results indicate a negative effect of stocking density on final weight, survival, alkalinity, NO2, PO43 and water consumption, and a positive effect on yield in Nile tilapia fingerling culture (1-20 g) in a low-salinity biofloc system with densities up to 1000 fish/m³.

scholarly journals The Influence of Larval Stage and Density on Oviposition Site-Selection Behavior of the Afrotropical Malaria Mosquito Anopheles coluzzii (Diptera: Culicidae)

2019 ◽  
Vol 57 (3) ◽  
pp. 657-666 ◽  
Author(s):  
Victor S Mwingira ◽  
Jeroen Spitzen ◽  
Leonard E G Mboera ◽  
José L Torres-Estrada ◽  
Willem Takken
Keyword(s):  
Site Selection ◽  
Larval Density ◽  
Interactive Effects ◽  
Olfactory Cues ◽  
Oviposition Site ◽  
Site Quality ◽  
Anopheles Coluzzii ◽  
Malaria Mosquito ◽  
Oviposition Site Selection ◽  
Negative Effect

Abstract In the selection of oviposition sites female mosquitoes use various cues to assess site quality to optimize survival of progeny. The presence of conspecific larvae influences this process. Interactive effects of oviposition site selection were studied in the malaria mosquito Anopheles coluzzii Coetzee & Wilkerson in dual- and no-choice assays, by exposing single gravid mosquitoes to oviposition cups containing 1) larvae of different developmental stages, 2) larvae-conditioned water (LCW), and 3) cups where visual cues of conspecific larvae were absent. Early-stage conspecific larvae had a positive effect on the oviposition response. By contrast, late stages of conspecific larvae had a negative effect. Oviposition choice was dependent on larval density. Moreover, in oviposition cups where larvae were hidden from view, late-stage larvae had a significant negative effect on oviposition suggesting the involvement of olfactory cues. LCW had no effect on oviposition response, indicating involvement of chemicals produced by larvae in vivo. It is concluded that the presence of larvae in a breeding site affects the oviposition response depending on the development stage of the larvae. These responses appear to be mediated by olfactory cues emitted by the larval habitat containing live larvae, resulting in the enhanced reproductive fitness of the females.

scholarly journals Lowering Stand Density Enhances Resiliency of Ponderosa Pine Forests to Disturbances and Climate Change

2019 ◽  
Vol 65 (4) ◽  
pp. 496-507 ◽  
Author(s):  
Jianwei Zhang ◽  
Kaelyn A Finley ◽  
Nels G Johnson ◽  
Martin W Ritchie
Keyword(s):  
Climate Change ◽  
Tree Growth ◽  
Ponderosa Pine ◽  
Tree Mortality ◽  
Ring Width ◽  
Basal Area ◽  
Stand Density ◽  
Site Quality ◽  
Climate Trends ◽  
Ponderosa Pine Forests

AbstractStand density affects not only structure and growth, but also the health of forests and, subsequently, the functions of forest ecosystems. Here, we integrated dendrochronology and repeated inventories for ponderosa pine research plots to determine whether long-term growth and mortality responded to climate trends and how varying stand density influenced the responses. The plots were established prior to 1975 on existing stands throughout northern California. Although annual temperature increased consistently for the last 65 years, ring-width indices produced by eliminating age and thinning effects failed to detect radial trend regardless of site quality. However, interannual variation for the indices was substantial, reflecting a strong influence of climate on tree growth. Plot-level basal area increments were significantly affected by tree mortality. Stand density index explained most variation of mortality. Lowering stand density enhanced remaining tree growth, reduced mortality, and increased stand resiliency to disturbances and climate change. Besides higher climate moisture indices or lower vapor pressure deficits, any treatments that improve tree vigor and reduce stress will have a similar effect to reducing stand density. Although neither biotic disturbances nor abiotic conditions can be controlled, forest managers can manage stand density appropriately to enhance resilience to climate change and disturbances.

scholarly journals Suitability of Mahseer Tor putitora (Hamilton) in Polyculture with Indian Major Carps

2014 ◽  
Vol 18 (2) ◽  
pp. 175-182
Author(s):  
MR Rahman ◽  
MS Rahman ◽  
MGQ Khan ◽  
S Mostary
Keyword(s):  
Labeo Rohita ◽  
Stocking Density ◽  
The Body ◽  
Catla Catla ◽  
Cirrhinus Mrigala ◽  
Indian Major Carps ◽  
Significant Difference ◽  
Tor Putitora ◽  
Negative Effect ◽  
Major Carps

An experiment on polyculture of mahseer with Indian major carps at same stocking density was carried out for a period of 10 months from February 1 to December 1, 2004 in six experimental ponds. There were three treatments with two replicates each. Treatment 1 was designed with catla (Catla catla), rohu (Labeo rohita) and mrigal (Cirrhinus mrigala), treatment 2 with catla (Catla catla), rohu (Labeo rohita) and mahseer (Tor putitora) while treatment 3 with catla (Catla catla), rohu (Labeo rohita), mrigal (Cirrhinus mrigala) and mahseer (Tor putitora). Mahseer of the treatment 2 was introduced instead of mrigal of treatment 1 and 50% of mrigal was replaced with mahseer in treatment 3. The stocking density in all the treatments was 30 fish/decimal (7500 fish/ha). The feeds were supplied at the rate of 3-7% of the body weight of fish. The gross and net productions recorded were 5362.78 and 5188.64, 5431.42 and 5262.32, 5357.11 and 5528.74 kg/ha/yr in treatments 1, 2 and 3 respectively. Though there was no significant difference (p>0.05) among the three treatments using ANOVA but the production in treatment-3 was slightly higher than treatments 1 and treatment 2. However, there was no negative effect of mahseer on the growth and production of Indian major carps. So, it can be concluded that polyculture of mahseer with Indian major carps (catla, rohu and mrigal) can be done in ponds.DOI: http://dx.doi.org/10.3329/pa.v18i2.18194 Progress. Agric. 18(2): 175 - 182, 2007

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