Douglasien-Provenienzversuch von 1961 in Nordwestdeutschland: Ergebnisse nach 38 Jahren

2012 ◽  
Vol 163 (3) ◽  
pp. 105-114
Author(s):  
Andreas Weller
Keyword(s):  
Wide Spectrum ◽  
Volume Growth ◽  
Climatic Conditions ◽  
Douglas Fir ◽  
Primary Data ◽  
Mean Annual Precipitation ◽  
Mean Temperature ◽  
Adaptive Capabilities ◽  
Provenance Trials

Douglas-fir provenance trials established 1961 in northwestern Germany: findings at the age of 38 years The Douglas-fir provenance trials established on 14 sites in northwestern Germany in 1961 are the basis for a comparison of 26 North American Douglas-fir provenances. The following assessment criteria were formulated: (1) How do the provenances differ with respect to total volume growth after 38 years? (2) Can climate-induced variations be observed in provenance values? (3) Do provenances differ in regard to branchiness? Because of non-orthogonal trial set-ups and plot-related influences, overall trial sites analysis called for a standardisation of interval-scaled primary data. Relative rank classes were calculated on the basis of a mean plot value. With respect to total volume growth, the provenances Tenas Creek (D47) as well as Molalla (D74) and Timber (D41/59) proved provenances with stable and outstanding productivity. Among the tested local climate elements “long-term annual mean temperature”, “mean annual precipitation” and “height above sea level” only the influence of long-term annual mean temperature is statistically relevant for productivity. Beside hardy ecotypes, which adapt to a wide spectrum of differing plot climates (e.g., Molalla [D74]), there are provenances with poor adaptive capabilities that react sensitively to local climatic conditions (e.g., Salmon Arm II [D46]). For the criterion “fine-branchiness”, the provenances Conrad Creek (D43), Ashford (D67) and Gold Hill (D83) show the best, the provenances Detroit (D76), Carson (D87) and Salmon Arm II (D46) the poorest results.

Response of coastal Douglas-fir and competing vegetation to repeated and delayed weed control treatments during early plantation development

2009 ◽  
Vol 39 (6) ◽  
pp. 1208-1219 ◽  
Author(s):  
Douglas A. Maguire ◽  
Douglas B. Mainwaring ◽  
Robin Rose ◽  
Sean M. Garber ◽  
Eric J. Dinger
Keyword(s):  
Weed Control ◽  
Seedling Growth ◽  
Volume Growth ◽  
Douglas Fir ◽  
Optimal Regime ◽  
Competitive Effects ◽  
Competing Vegetation ◽  
Plantation Development ◽  
Age Shift

A key silvicultural decision in managing young conifer plantations is determining the number and timing of release treatments to control competing vegetation. Three coastal Douglas-fir ( Pseudotsuga menziesii (Mirb.) Franco) plantations were treated under eight alternative herbicide regimes during the first 5 years after planting to test treatment effects on vegetation dynamics and seedling growth. After termination of herbicide treatments, competing vegetation developed at a rate similar to that of check plots, reaching 40%–60% cover in the first growing season and approaching 100% by the third. Recovery of competing vegetation was slightly more rapid with greater number of previous releases. Annual volume growth of seedlings was negatively correlated with current cover of competing vegetation, but competitive effects from previous years were fully accounted for by initial tree size. Under 4 years of release, delaying treatment by 1 year reduced volume attained at the end of 5 years by about 15%. Plots receiving 5 consecutive years of weed control reached the 5 year volume of check plots in only 3.9 years, implying an age shift of 1.1 years. Increasing the number of operational release treatments significantly improved seedling growth in the short term, but long-term growth effects must be monitored to determine the economically optimal regime.

Reconstructing crop yield variability in Finland: Long-term perspective of the cultivation history on the agricultural periphery since ad 760

The Holocene ◽  
2016 ◽  
Vol 27 (1) ◽  
pp. 3-11 ◽  
Author(s):  
Heli Huhtamaa ◽  
Samuli Helama
Keyword(s):  
Crop Production ◽  
Wide Spectrum ◽  
Climatic Conditions ◽  
Yield Ratio ◽  
Study Region ◽  
Crop Cultivation ◽  
The North ◽  
Long Run ◽  
High Yields

Lack of documentation on past harvest fluctuations limits the exploration of long-term trends in crop production and agricultural adaptation strategies. A long-term perspective is needed, however, to understand the wide spectrum of potential human responses to environment and climate change. Therefore, we used tree-ring density series as proxy data to reconstruct climate-mediated yield ratio (harvested grain in relation to sown) in central and northern Finland over the period ad 760–2000. The reconstruction explains 50% of the variance in recorded yield ratio variability over the calibration period (ad 1866–1921). The reconstruction illustrated several intervals of increased and reduced yield ratio over the past 13 centuries. The long-term development of the agricultural prerequisites is characterized by distinct intervals defined statistically as ad 760–1106 (highest yield ratios), 1107–1451, 1452–1694, 1695–1911 (lowest yield ratios) and 1912 onwards. The results provide insight into the establishment and development of crop cultivation in the agricultural margin. The reconstruction suggests that continuous crop cultivation was established in the study region during a favourable period of climatic conditions supporting high yields. Thereafter, the climate-mediated yield ratio declined in the long run until the turn of the 20th century. Periods of agricultural transformations, those previously demonstrated in pollen data and historical documents, followed the onsets of the low yield ratio phases indicated by our reconstruction. Thus, we suggest that ever since the establishment of crop cultivation, climate can be considered as an important factor contributing to the development of the agricultural history in the north.

Surviving and growing in the post-Covid world: the case of Indian hotels

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Raju Majumdar
Keyword(s):  
Financial Management ◽  
Wide Spectrum ◽  
Cash Flows ◽  
Primary Data ◽  
New Normal ◽  
Content Type ◽  
Select Group ◽  
Human Cost ◽  
The Impact

PurposeAs the world tries to come to terms with the exact economic and human cost of the Covid-19 pandemic, businesses are trying to discern and act on the implications of the “new normal” in order to survive and grow. Amongst all the industries impacted by the Covid-19 pandemic, travel and tourism has been the hardest hit. Operators across the value chain are trying to innovate and improvise in order to mitigate the impact of the pandemic on cash flows and working capital. The primary purpose of this paper then is to take a closer look at the measures adopted by the Indian hotel industry to restore revenues, conserve resources and attain greater operational and cost efficiencies in the midst of the Covid-19 crisis. The article also brings to the fore the growth-enhancing measures adopted by the industry in anticipation of a “new normal” in the post-Covid world.Design/methodology/approachThis study is based on primary data collected via a survey, followed by a series of interviews with a select group of senior finance managers from a wide spectrum of hotels based in India.FindingsOur findings suggest that Indian hotels have adopted several measures to enhance cash flows/revenues, reduce operating costs and cash outflows and conserve resources in order to tide themselves over during the crisis. Prominent cash flow–enhancing measures include price drops on special offers and reductions on list prices. Cost-cutting measures include economizing on energy consumption, reductions in labour costs and the postponement of maintenance expenses and discretionary spending. Resource conservation measures that have been adopted focus on postponement of capital expenditure and an increasing shift to localizing supply chains. Growth-enhancing measures adopted by the industry in anticipation of the long-term “new normal” include restructuring of the workforce and measures aimed at attracting domestic tourists and increasing product diversity.Originality/valueThis study attempts to understand the short-term and long-term financial management strategies adopted by Indian hotels in the face of unprecedented disruption caused by the Covid-19 pandemic. To the best of our knowledge, this paper is the first of its kind in the Indian context.

2500-year cultural sequence in the Massim region of eastern Papua New Guinea reflects adaptive strategies to small islands and changing climate regimes since Lapita settlement

The Holocene ◽  
2020 ◽  
Vol 30 (7) ◽  
pp. 1075-1090
Author(s):  
Ben Shaw ◽  
Simon Coxe ◽  
Vincent Kewibu ◽  
Jemina Haro ◽  
Emily Hull ◽  
...  
Keyword(s):  
Large Scale ◽  
Social Dynamics ◽  
New Guinea ◽  
Climatic Conditions ◽  
Ice Age ◽  
Adaptive Plasticity ◽  
Sea Levels ◽  
Adaptive Capabilities ◽  
Dry Conditions

Islands present significant technological and ecological challenges for long-term human settlement, with archaeological investigations of islands globally able to shed light on the adaptive plasticity of cultural groups to changing climatic regimes. The Massim islands of eastern New Guinea significantly reduced in size throughout the Holocene (⩽11.7 kya), providing a unique opportunity to investigate the long-term adaptive capabilities of humans to changing island ecosystems. Here, we report a 2500-2300 year cultural sequence on Nimowa Island in the Louisiade Archipelago of the Massim region which began with the arrival of a late Lapita population during initial beachfront development. Sediment analyses indicate earlier settlement on the island would not have been possible as the coastline was unstable until near-modern sea levels were reached. The island was abandoned from 1290 to 530 cal. BP during a period of unusually dry conditions (‘Medieval Climate Anomaly’) and probable freshwater shortages. Re-settlement coincided with wetter climatic conditions (‘Little Ice Age’), associated with the establishment of large villages, the earliest expression of local pottery traditions and the onset of large-scale regional exchange networks. Import of non-local obsidian reflects two pulses of interaction followed by periods of increased isolation. With the absence of high-quality lithic resources, shell, coral and bone were used as a locally available alternative for tool production. Increased cyclone frequency from ~500 cal. BP greatly increased beach volume in the island and coastal New Guinea, which facilitated the movement of populations onto smaller islands. A late prehistoric shift in settlement patterns had a profound impact on regional social dynamics.

Beyond the mean: long-term variabilities in precipitation and temperature on the Qinghai-Tibetan Plateau

2021 ◽  
Author(s):  
Tong Guo ◽  
Yanhong Tang
Keyword(s):  
Climate Change ◽  
Tibetan Plateau ◽  
Interannual Variability ◽  
Daily Precipitation ◽  
Mean Annual Precipitation ◽  
High Altitudes ◽  
Annual Variability ◽  
Mean Temperature ◽  
Precipitation And Temperature

AbstractLong-term variabilities in daily precipitation and temperature are critical for assessing the impacts of climate change on ecosystems. We characterized intra- and interannual variabilities in daily precipitation and temperature obtained from 1960 to 2015 at 78 meteorological stations on the Qinghai-Tibetan Plateau. The results show that 1) The intra-annual variability of daily precipitation increases for 55 meteorological stations with a rate of 0.08 mm per decade. In contrast, the intra-annual variability markedly decreases for daily mean, daytime mean, and nighttime mean temperatures with a rate of 0.09, 0.07, and 0.12 °C per decade, respectively at 90% or more of stations. 2) Variabilities of daily precipitation and temperatures are quite sensitive to high altitudes (> 3500 m). The intra- and interannual variabilities of daily precipitation significantly decrease at 1.0 and 0.07 mm per 1000 m, respectively. However, variations of high altitudes increase the intra- and interannual variabilities of daily mean temperature at 1.0 °C and 0.2 °C per 1000 m. Moreover, the interannual variability of nighttime mean temperature varies at 0.3 °C per 1000 m, the fastest rate among three temperature indices. 3) A larger mean annual precipitation is accompanied by a higher intra- and interannual variability of daily precipitation on the Qinghai-Tibetan Plateau; however, a higher mean annual temperature leads to lower variabilities of daily temperatures. This study illustrates that long-term climatic variability is understudied in alpine ecosystems characterized by high climatic sensitivity. Precipitation and temperature variabilities should be characterized to improve predictions of vulnerable ecosystems responding to climate change.

Modelling of Moisture Movement in Wood during Outdoor Storage

2001 ◽  
Vol 6 (2) ◽  
pp. 3-14 ◽  
Author(s):  
R. Baronas ◽  
F. Ivanauskas ◽  
I. Juodeikienė ◽  
A. Kajalavičius
Keyword(s):  
Experimental Data ◽  
Finite Difference ◽  
Climatic Conditions ◽  
Two Dimensional ◽  
Moisture Movement ◽  
Finite Difference Technique ◽  
Long Term Storage ◽  
Space Formulation ◽  
Term Storage

A model of moisture movement in wood is presented in this paper in a two-dimensional-in-space formulation. The finite-difference technique has been used in order to obtain the solution of the problem. The model was applied to predict the moisture content in sawn boards from pine during long term storage under outdoor climatic conditions. The satisfactory agreement between the numerical solution and experimental data was obtained.

DROUGHT OCCURRENCE UNDER LITHUANIAN CLIMATIC CONDITIONS

2015 ◽  
Author(s):  
Laima TAPARAUSKIENĖ ◽  
Veronika LUKŠEVIČIŪTĖ
Keyword(s):  
Meteorological Data ◽  
Standardized Precipitation Index ◽  
Vegetation Period ◽  
Climatic Conditions ◽  
Precipitation Record ◽  
Calculation Step ◽  
Drought Conditions ◽  
The Standardized Precipitation Index ◽  
June July

This study provides the analysis of drought conditions of vegetation period in 1982-2014 year in two Lithuanian regions: Kaunas and Telšiai. To identify drought conditions the Standardized Precipitation Index (SPI) was applied. SPI was calculated using the long-term precipitation record of 1982–2014 with in-situ meteorological data. Calculation step of SPI was taken 1 month considering only vegetation period (May, June, July, August, September). The purpose of investigation was to evaluate the humidity/aridity of vegetation period and find out the probability of droughts occurrence under Lithuanian climatic conditions. It was found out that according SPI results droughts occurred in 14.5 % of all months in Kaunas region and in 15.8 % in Telšiai region. Wet periods in Kaunas region occurred in 15.8 %, and in Telšiai region occurrence of wet periods was – 18.8 % from all evaluated months. According SPI evaluation near normal were 69.7 % of total months during period of investigation in Kaunas and respectively – 65.5 % in Telšiai. The probability for extremely dry period under Lithuania climatic conditions are pretty low – 3.0 % in middle Lithuania and 2.4 % in western part of Lithuania.

SELECTION WORK TO IMPROVE PRODUCTIVE AND BREWING QUALITIES OF SPRING BARLEY

1970 ◽  
pp. 38-40
Author(s):  
О. V. Levakova ◽  
L. М. Eroshenko ◽  
А. N. Eroshenko
Keyword(s):  
Protein Content ◽  
Spring Barley ◽  
Humus Content ◽  
Stability Index ◽  
Field Studies ◽  
Climatic Conditions ◽  
Extract Content ◽  
Labile Phosphorus ◽  
Loam Soil

The article presents and analyzes data of competitive varietal testing of promising varieties and lines of spring barley for yield and brewing qualities. Field studies were conducted in 2014–2017 on dark gray forest heavy loam soil. Agrochemical parameters are total nitrogen – 0.24%, humus content in a layer of 0-40 cm (according to Tyurin) – 5.19%, hydrolysis nitrogen – 123.5 mg / kg, salt extract pH – 4.92 mg-eq / 100g; labile phosphorus - 34.6 mg / 100g, labile potassium – 20.0 mg / 100g. The forerunner is winter wheat. Meteorological conditions in the years of research differed from each other and from the average long-term value. Barley samples were assessed by the protein content in the grain (GOST 10846-91), extract content (GOST 12130-77), weight 1000 grains (GOST 10842-89). Ecological plasticity was determined by the method proposed by E.D. Nettevich, A.I. Morgunov and M.I. Maksimenko, stability index (Ľ) by A. A. Gryaznov, indicator of stability level (Puss) by E. D. Nettevich and A. I. Morgunov. The main measure for assessing quality indicators is protein content. Many other biochemical and technological features of grain depend on its level. The experimental data convincingly testify to the significant influence of the soil and climatic conditions on the yield and, especially, on the brewing qualities of barley in the conditions of the Central Region of the Nonchernozem Zone. According to the studied traits, new valuable varieties Nadezhny, Sir, Noble and selection lines 141 / 1-09 h 746, 23 / 1-10 h 784, distinguished by high adaptability and resistance to adverse environmental factors, have been identified.

Wachstum und Wertleistung der Douglasie in Abhängigkeit von der Standraumgestaltung

2012 ◽  
Vol 163 (3) ◽  
pp. 96-104 ◽  
Author(s):  
Joachim Klädtke ◽  
Ulrich Kohnle ◽  
Edgar Kublin ◽  
Andreas Ehring ◽  
Hans Pretzsch ◽  
...  
Keyword(s):  
Wood Quality ◽  
Volume Growth ◽  
Static Stability ◽  
Douglas Fir ◽  
Breast Height ◽  
Monetary Analysis ◽  
Starting Conditions ◽  
Tree Number ◽  
Clear Differentiation ◽  
Further Development

Growth and value production of Douglas-fir under varying stand densities The investigation is focused on the effects of initial tree number and thinning on growth and value performance of Douglas-fir stands. Data base is a coordinated Douglas-fir spacing experiment in South Germany, started 40 years ago and comprising variants of tree numbers with 500, 1,000, 2,000 and 4,000 Douglas-firs per hectare. The treatment was performed according to a standardized experiment program. The results show that at low initial tree numbers, the diameter on breast height (DBH) of (pre)dominant trees at the beginning of the observations (with 12 m top height) is bigger than at higher initial plant numbers. Accordingly, the quotient of height (H) to DBH (as an indicator for tree's static stability) is lower. The further development of DBH and H/DBH quotient is decisively determined by stand treatment, which superimposes the effect of the initial tree number. The total volume growth shows a clear differentiation, too, the variants with initially high tree numbers appearing on top. In the monetary analysis, this ranking is reversed: despite a supposed inferior wood quality, the variants with lower initial tree numbers clearly outperform the ones with higher numbers in terms of value. From these results, the following silvicultural recommendations for Douglas-fir can be derived: the initial tree numbers should be in the range from 1,000 to 2,000 plants per hectare. On technically not accessible sites, even lower tree numbers may come into question. The strong influence of stand treatment on DBH and H/DBH development highlights the problem of postponed thinnings, for this causes growth and stability losses even under favorable starting conditions in terms of competition.

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