scholarly journals Impacts of Long-Term Diameter-Limit Harvesting on Residual Stands of Red Spruce in Maine

2004 ◽  
Vol 21 (2) ◽  
pp. 69-73 ◽  
Author(s):  
Kerry A. Sokol ◽  
Michael S. Greenwood ◽  
William H. Livingston
Keyword(s):  
Positive Selection ◽  
Growth Rates ◽  
Growth Patterns ◽  
Growth Potential ◽  
Red Spruce ◽  
Growing Stock ◽  
Spruce Stands ◽  
Selection Harvesting ◽  
Residual Tree

Abstract Diameter-limit harvesting has long been suspected as a dysgenic forestry practice, but a conclusive, practical demonstration of the effects of this selection technique on residual tree performance is lacking. To determine the effects of repeated diameter-limit harvesting on the phenotypes of residual trees, we compared radial growth patterns of residual red spruce trees (with ages greater than 100 years) after diameter-limit harvests with those of residual trees in stands subjected to positive selection harvesting. After nearly 50 years of repeated harvesting, residual trees in the diameter-limit stands were nearly 40% smaller and had grown 32% slower than residual trees in positive selection stands. Furthermore, diameter-limit residuals were initially smaller and remained significantly smaller than positive selection residuals throughout their lifespan, despite major release events. After release, the diameter-limit trees responded with increased growth rates, but the increase was relatively small. Growth rates were consistently and significantly lower for diameter-limit residuals until the final 20 yr when growth rates in each treatment converged. Our results indicate that red spruce stands subjected to repeated diameter-limit harvesting will develop progressively less valuable growing stock with limited growth potential.

scholarly journals Seasonal patterns of pasture production in the Bay of Plenty and Waikato

1991 ◽  
pp. 67-72
Author(s):  
J.A. Baars ◽  
G.J. Goold ◽  
M.F. Hawke ◽  
P.J. Kilgarriff ◽  
M.D. Rolm
Keyword(s):  
Growth Rates ◽  
Early Spring ◽  
Early Summer ◽  
Growth Patterns ◽  
Climatic Data ◽  
Large Contribution ◽  
Pasture Production ◽  
Summer Peak ◽  
The Difference

Patterns of pasture growth were measured on 3 farms in the Bay of Plenty (BOP) and at No2 Dairy (Ruakura Agricultural Centre) in the Waikato from 1989 to 199 1. A standardised trim technique with cages and 4-weekly cutting under grazing was used. Long-term seasonal growth patterns, using a predictive pasture model, were also simulated. Simulated pasture growth from long-term climatic data shows that pasture growth rates are higher in winter, early spring and late autumn in the BOP than the Waikato. However, the actual measurements over the 2 years show that pasture growth over the latter periods is lower at the BOP sites than at the Waikato site. In the BOP the spring peak is much later than in the Waikato while an early summer peak, with higher growth rates than in the Waikato, occurred in the BOP. No such summer peak was evident in the Waikato. The difference between the two regions is caused by the large contribution of subtropical grasses to sward production in summer and autumn, The prolific summer growth of subtropical grasses may explain the low ryegrass content and low pasture production in winter. The lower than expected autumn, winter, spring production may also becaused by low clover content, possibly a result of competition from subtropical grasses and a sulphur deficiency. The apparent low amount of nitrogen fixed by clover may explain the low rates of pasture production over the cooler season. Applications of nitrogen fertiliser may substantially increase dry matter production from April to September. Keywords pasture,simulation,subtropical grasses, Paspalum, Digitaria sanguinalis, growth rates

scholarly journals Long term pasture growth patterns for Southland New Zealand: 1978 to 2012

2012 ◽  
pp. 147-151
Author(s):  
L.C. Smith
Keyword(s):  
New Zealand ◽  
Key Words ◽  
Growth Rates ◽  
Initial Period ◽  
Farm Management ◽  
Growth Patterns ◽  
Annual Growth ◽  
Management Systems ◽  
Summer Peak

Pasture growth rates for Southland were reported by several researchers in the late 1970s and early 1980s. However, pasture species and farm management systems have changed somewhat since then. This paper presents data from measurements at Woodlands, near Invercargill, that have been ongoing since 1977, and discusses some of the variability that has occurred over the years. Measurement of pasture growth was done using a standardised cutting method known as "rate of growth" or moving cages, with measurements every 3 weeks. Annual yields were calculated from 1 June to 31 May of the next year. The pasture growth at Woodlands is characterised by a spring-summer peak of growth followed by a deep winter trough where growth is minimal. Long-term average annual growth was 11.8 t DM/ha for older 'Ruanui' based pasture and 12.7 t DM/ ha for newer 'Nui'/'Supreme'/'Greenstone' ryegrass based pasture. However the newer pasture produced considerably more (ca.14.2 t DM/ha/year) for an initial period of 3 years, after which time the production dropped back to be similar to the old pasture (ca.12.0 t DM/ha/year). Key words. pasture growth; long-term; annual variability

scholarly journals Comparison of various growth functions for predicting long-term stand development associated with different initial spacing in 64-year-old Japanese cedar (Cryptomeria japonica (L.f.) D. Don) plantations

2021 ◽  
Vol 64 (1) ◽  
pp. 87-97
Author(s):  
Che-Yu Shih ◽  
Tian-Ming Yen ◽  
Ya-Nan Wang
Keyword(s):  
Cryptomeria Japonica ◽  
Stand Density ◽  
Japanese Cedar ◽  
Growth Patterns ◽  
Growth Potential ◽  
Stand Development ◽  
Initial Growth ◽  
Growth Functions ◽  
Initial Spacing

Establishing a plantation with varied distances between trees is one way to control stand density in an initial growth stage. Understanding how stand growth patterns are influenced by initial spacing can help maximize growth and yield. The purpose of this study was to examine the long-term effects of different patterns of initial tree spacing on stand development. A spacing trial with five initial distances, namely, treatments I: 1×1 m, II: 2×2 m, III: 3×3 m, IV: 4×4 m, and V: 5×5 m, was established in 1950 in Japanese cedar (Cryptomeria japonica (L.f.) D. Don) plantations in central Taiwan, managed by the Experimental Forest of National Taiwan University. Each treatment had three repetitions, and all plots were surveyed from 1955 to 2014, with eight records for each time series. We simultaneously employed six growth functions to predict stand basal area growth for each plot and assessed their predictability using the root mean square error (RMSE) as a criterion. Consequently, a total of twelve plots covering all treatments except treatment I, each with six RMSEs resulting from various models, were obtained. The repeated measures analysis of variance approach was adopted to compare predictability among models. The Richards growth function performed the best compared to all the other models. As a result, this model was used to analyse stand development following different initial spacing. We found that the predicted curves could effectively exhibit the growth patterns resulting from different initial spacing. Moreover, the parameters help explain some characteristics of stand development, such as growth potential and maximum growth rate achieved (t max). As a result, a clear trend emerged, showing that, with decreasing initial spacing, the growth potential increased and the t max decreased. These results provided valuable information for managing the stand density of this conifer.

Intercalary growth causes geometric length expansion in Methuselah’s beard lichen (Usnea longissima)

Botany ◽  
2008 ◽  
Vol 86 (10) ◽  
pp. 1224-1232 ◽  
Author(s):  
Jørund Rolstad ◽  
Erlend Rolstad
Keyword(s):  
Growth Rates ◽  
Doubling Time ◽  
Biomass Accumulation ◽  
Growth Patterns ◽  
Growth Potential ◽  
Usnea Longissima ◽  
Geometric Length ◽  
Favorable Conditions ◽  
Slow Growing ◽  
Lichen Growth

In sharp contrast to many slow-growing lichens, some epiphytic pendulous and foliose lichens display striking biomass accumulation in favorable habitats. Whereas lichen growth rates have received considerable attention, comparatively few detailed studies of growth patterns have been carried out. Generally, most lichens seem to grow apically, with only pseudomeristomatic tissue confined to lobe margins and branch tips. However, some species appear to retain the capacity to expand throughout the thallus, thereby increasing their growth potential. Such intercalary growth processes have proved difficult to confirm in the field for two- and three-dimensionally growing folious and fruticose forms. Using transplants of the conspicuous, one-dimensionally growing Usnea longissima Ach., we document that intercalary growth actually does occur, with thalli expanding geometrically in length with a doubling time of less than a year under favorable conditions.

The Reproduction Vector of the Russian Economy: 1999-2007

2008 ◽  
pp. 94-109 ◽  
Author(s):  
D. Sorokin
Keyword(s):  
Economic Policy ◽  
Human Capital ◽  
Growth Rates ◽  
Developed Countries ◽  
Gdp Per Capita ◽  
Real Sector ◽  
Russian Economy ◽  
Per Capita ◽  
The Developed Countries

The problem of the Russian economy’s growth rates is considered in the article in the context of Russia’s backwardness regarding GDP per capita in comparison with the developed countries. The author stresses the urgency of modernization of the real sector of the economy and the recovery of the country’s human capital. For reaching these goals short- or mid-term programs are not sufficient. Economic policy needs a long-term (15-20 years) strategy, otherwise Russia will be condemned to economic inertia and multiplying structural disproportions.

CURRENT STATE AND DEVELOPMENT PERSPECTIVES OF THE CASPIAN SPRAT FISHERIES

2018 ◽  
pp. 69-75
Author(s):  
Tatiana Vasilievna Pomogaeva ◽  
Aliya Ahmetovna Aseinova ◽  
Yuriy Aleksandrovich Paritskiy ◽  
Vjacheslav Petrovich Razinkov
Keyword(s):  
Food Item ◽  
Growth Potential ◽  
North West ◽  
Marine Fishery ◽  
The North ◽  
Current State ◽  
West Part ◽  
Eggs And Larvae ◽  
Intensive Growth

The article presents annual statistical data of the Caspian Research Institute of Fishery. There has been kept track of the long term dynamics of the stocks of three species of Caspian sprat (anchovy, big-eyed kilka, sprat) and investigated a process of substituting a food item of sprats Eurytemora grimmi to a small-celled copepod species Acartia tonsa Dana. According to the research results, there has been determined growth potential of stocks of each species. Ctenophoran-Mnemiopsis has an adverse effect on sprat population by eating fish eggs and larvae. Ctenophoram - Mnemiopsis is a nutritional competitor to the full-grown fishes. The article gives recommendations on reclamation of stocks of the most perspective species - common sprat, whose biological characteristics helped not to suffer during Ctenophoram outburst and to increase its population during change of the main food item. Hydroacoustic survey data prove the intensive growth of common sprat biomass in the north-west part of the Middle Caspian. According to the results of the research it may be concluded that to realize the volumes of recommended sprat catch it is necessary to organize the marine fishery of common sprat at the Russian Middle Caspian shelf.

INTRAUTERINE GROWTH RETARDATION - A REVIEW ARTICLE

2018 ◽  
pp. 184-195
Author(s):  
Minh Son Pham ◽  
Vu Quoc Huy Nguyen ◽  
Dinh Vinh Tran
Keyword(s):  
Fetal Growth ◽  
Gestational Age ◽  
Small For Gestational Age ◽  
Fetal Growth Restriction ◽  
Growth Restriction ◽  
Growth Potential ◽  
National Guidelines ◽  
Intrauterine Growth ◽  
No Gold Standard

Small for gestational age (SGA) and fetal growth restriction (FGR) is difficult to define exactly. In this pregnancy condition, the fetus does not reach its biological growth potential as a consequence of impaired placental function, which may be because of a variety of factors. Fetuses with FGR are at risk for perinatal morbidity and mortality, and poor long-term health outcomes, such as impaired neurological and cognitive development, and cardiovascular and endocrine diseases in adulthood. At present no gold standard for the diagnosis of SGA/FGR exists. The first aim of this review is to: summarize areas of consensus and controversy between recently published national guidelines on small for gestational age or fetal growth restriction; highlight any recent evidence that should be incorporated into existing guidelines. Another aim to summary a number of interventions which are being developed or coming through to clinical trial in an attempt to improve fetal growth in placental insufficiency. Key words: fetal growth restriction (FGR), Small for gestational age (SGA)

scholarly journals Imitated Whole Tree Harvesting Show Negligible Effect on Economic Value of Spruce Stands

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 841
Author(s):  
Iveta Desaine ◽  
Annija Kārkliņa ◽  
Roberts Matisons ◽  
Anna Pastare ◽  
Andis Adamovičs ◽  
...  
Keyword(s):  
Norway Spruce ◽  
Economic Value ◽  
Forest Types ◽  
Spruce Stands ◽  
The Difference ◽  
Growing Conditions ◽  
Whole Tree Harvesting ◽  
Whole Tree ◽  
Tree Harvesting

The increased removal of forest-derived biomass with whole-tree harvesting (WTH) has raised concerns about the long-term productivity and sustainability of forest ecosystems. If true, this effect needs to be factored in the assessment of long-term feasibility to implement such a drastic forest management measure. Therefore, the economic performance of five experimental plantations in three different forest types, where in 1971 simulated WTH event occurred, was compared with pure, planted and conventionally managed (CH) Norway spruce stands of similar age and growing conditions. Potential incomes of CH and WTH stands were based on timber prices for period 2014–2020. However, regarding the economics of root and stump biomass utilization, they were not included in the estimates. In any given price level, the difference of internal rate of return between the forest types and selected managements were from 2.5% to 6.2%. Therefore, Norway spruce stands demonstrate good potential of independence regardless of stump removal at the previous rotation.

Treatment of Unilateral Cleft Lip and Palate Patient With Intraoral Tooth Tissue Borne Distractor and Facemask Therapy: A Case Report

2021 ◽  
pp. 105566562199336
Author(s):  
Akansha Bansal Agrawal ◽  
Harshavardhan Kidiyoor ◽  
Anand K. Patil Morth
Keyword(s):  
Case Report ◽  
Cleft Lip ◽  
Cleft Lip And Palate ◽  
Face Mask ◽  
Rapid Maxillary Expansion ◽  
Growth Potential ◽  
Maxillary Expansion ◽  
Long Term Stability ◽  
Tooth Tissue

This case report demonstrates the successful use of intraoral distractor/hygenic rapid expander (HYRAX) for rapid maxillary expansion in anteroposterior direction with an adjunctive use of face mask therapy for anterior orthopedic traction of maxillary complex in a cleft patient with concave profile. The patient was a 13-year-old girl who reported with a chief complaint of backwardly positioned upper jaw and a severely forward positioned lower jaw. Therefore, a treatment was chosen in which acrylic bonded rapid maxillary expansion was done with tooth tissue borne intraoral distractor/HYRAX having a different activation schedule along with Dr Henri Petit facemask to treat maxillary retrognathism. As a result, crossbite got corrected and attained a positive jet with no bone loss in cleft area over a period of 5 months which was followed by fixed mechanotherapy achieving a well settled occlusion in 1 year. After completion of expansion and fixed mechanotherapy, ANB became +1 post-treatment which was −4 pretreatment. The prognathic profile was markedly improved by expansion and taking advantage of the remaining growth potential, thus minimizing the chances of surgery later in life. This provided a viable alternative to orthognathic surgery with good long-term stability.

scholarly journals Long-term photoacclimation ofHaslea ostrearia(Bacillariophyta): effect of irradiance on growth rates, pigment content and photosynthesis

1999 ◽  
Vol 34 (2) ◽  
pp. 109-115 ◽  
Author(s):  
J.-L. Mouget ◽  
G. Tremblin ◽  
A. Morant-Manceau ◽  
M. Morançais ◽  
J.-M. Robert
Keyword(s):  
Growth Rates ◽  
Pigment Content
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