The disturbance regime of Norway spruce forests in Bulgaria

2015 ◽  
Vol 45 (9) ◽  
pp. 1143-1153 ◽  
Author(s):  
Momchil Panayotov ◽  
Peter Bebi ◽  
Nickolay Tsvetanov ◽  
Neno Alexandrov ◽  
Lucinda Laranjeiro ◽  
...  
Keyword(s):  
Norway Spruce ◽  
Large Scale ◽  
Natural Disturbance ◽  
Disturbance Regime ◽  
Forest Reserves ◽  
Spruce Forests ◽  
The Past ◽  
Natural Range ◽  
Old Trees

Natural disturbances are among the most important factors that shape forest dynamics and forest landscapes. However, the natural disturbance regime of Norway spruce (Picea abies (L.) Karst.) forests in Europe is not well understood. We studied the disturbance regimes in three forest reserves in Bulgaria (Parangalitsa, Bistrishko branishte, and Beglika), which are representative of the range of conditions typical for P. abies ecosystems in central and southern Europe. Our data indicated that large-scale disturbances were most numerous in forests that were between 120 and 160 years old, those with unimodal diameter at breast height (DBH) distributions, and especially those located in vulnerable topographic settings. Wind disturbances ranged up to 60 ha, followed in one case by a 200 ha Ips typographus (Linnaeus, 1758) outbreak. Older forests and those with more complex structures (i.e., reverse-J DBH) were characterized by numerous small gaps but were also affected by a few larger disturbances. In some old-growth forests at highly productive sites, gaps could be so numerous that the long-term existence of old trees may become an exception. Over the past centuries, the natural range of variability of these Norway spruce forests in Bulgaria appears to have been shaped mostly by wind and bark beetle disturbances of various sizes.

scholarly journals Global climatology and trends in convective environments from ERA5 and rawinsonde data

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Mateusz Taszarek ◽  
John T. Allen ◽  
Mattia Marchio ◽  
Harold E. Brooks
Keyword(s):  
Large Scale ◽  
Climate Models ◽  
Global Climate ◽  
Convective Available Potential Energy ◽  
Global Climate Models ◽  
Convective Precipitation ◽  
The Past ◽  
The Tropics ◽  
Rawinsonde Data

AbstractGlobally, thunderstorms are responsible for a significant fraction of rainfall, and in the mid-latitudes often produce extreme weather, including large hail, tornadoes and damaging winds. Despite this importance, how the global frequency of thunderstorms and their accompanying hazards has changed over the past 4 decades remains unclear. Large-scale diagnostics applied to global climate models have suggested that the frequency of thunderstorms and their intensity is likely to increase in the future. Here, we show that according to ERA5 convective available potential energy (CAPE) and convective precipitation (CP) have decreased over the tropics and subtropics with simultaneous increases in 0–6 km wind shear (BS06). Conversely, rawinsonde observations paint a different picture across the mid-latitudes with increasing CAPE and significant decreases to BS06. Differing trends and disagreement between ERA5 and rawinsondes observed over some regions suggest that results should be interpreted with caution, especially for CAPE and CP across tropics where uncertainty is the highest and reliable long-term rawinsonde observations are missing.

Salvage harvesting – past lessons and future issues

2006 ◽  
Vol 82 (1) ◽  
pp. 48-53 ◽  
Author(s):  
David Lindenmayer
Keyword(s):  
Environmental Impacts ◽  
Large Scale ◽  
Natural Disturbance ◽  
Forest Planning ◽  
Salvage Logging ◽  
Eastern Australia ◽  
Wide Range ◽  
Natural Resource Managers ◽  
Salvage Harvesting

The increasing prevalence and/or increasing intensity of large-scale natural disturbance events in forests means that post-disturbance salvage logging is becoming more widespread. Salvage logging can have a wide range of environmental impacts, but some of these are not well known or not well understood by policy makers and natural resource managers. Some of these impacts are briefly summarized in this paper. Improved long-term forest planning needs to be embraced that takes into account the not only the environmental but also the social and environmental impacts of salvage harvesting. Past mistakes and future opportunities associated with salvage harvesting are illustrated by a case study from the Lower Cotter Catchment in south-eastern Australia. Key words: salvage harvesting, natural disturbance, environmental impacts, ecologically sustainable forestry, forest planning, long-term forest sustainability

scholarly journals Mixed-severity natural disturbance regime dominates in an old-growth Norway spruce forest of northwest Russia

2015 ◽  
Vol 27 (2) ◽  
pp. 400-413 ◽  
Author(s):  
Tatiana Khakimulina ◽  
Shawn Fraver ◽  
Igor Drobyshev
Keyword(s):  
Norway Spruce ◽  
Natural Disturbance ◽  
Spruce Forest ◽  
Disturbance Regime ◽  
Old Growth ◽  
Norway Spruce Forest

Trends in the frequency, extent, and severity of spruce budworm outbreaks in eastern Canada

1983 ◽  
Vol 13 (4) ◽  
pp. 539-547 ◽  
Author(s):  
J. R. Blais
Keyword(s):  
20Th Century ◽  
Large Scale ◽  
Spruce Budworm ◽  
Forest Composition ◽  
Eastern Canada ◽  
Clear Cutting ◽  
The Past ◽  
Spruce Stands ◽  
History Of

The history of spruce budworm (Choristoneurafumiferana (Clem.)) outbreaks for the past 200 to 300 years, for nine regions in eastern Canada, indicates that outbreaks have occurred more frequently in the 20th century than previously. Regionally, 21 outbreaks took place in the past 80 years compared with 9 in the preceding 100 years. Earlier infestations were restricted to specific regions, but in the 20th century they have coalesced and increased in size, the outbreaks of 1910, 1940, and 1970 having covered 10, 25, and 55 million ha respectively. Reasons for the increase in frequency, extent, and severity of outbreaks appear mostly attributable to changes caused by man, in the forest ecosystem. Clear-cutting of pulpwood stands, fire protection, and use of pesticides against budworm favor fir–spruce stands, rendering the forest more prone to budworm attack. The manner and degree to which each of these practices has altered forest composition is discussed. In the future, most of these practices are expected to continue and their effects could intensify, especially in regions of recent application. Other practices, including large-scale planting of white spruce, could further increase the susceptibility of forest stands. Forest management, aimed at reducing the occurrence of extensive fir–spruce stands, has been advocated as a long-term solution to the budworm problem. The implementation of this measure at a time when man's actions result in the proliferation of fir presents a most serious challenge to forest managers.

scholarly journals DEPRESI INDUCED STEROID: STUDI KASUS

2019 ◽  
Vol 1 (2) ◽  
pp. 1-4
Author(s):  
Saiful Batubara
Keyword(s):  
Rheumatoid Arthritis ◽  
Systemic Lupus Erythematosus ◽  
Immune Response ◽  
Depressed Mood ◽  
Lupus Erythematosus ◽  
Natural Disturbance ◽  
Systemic Lupus ◽  
The Past ◽  
Back Ground

Back Ground: Depression is a natural disturbance of feeling that is characterized by feelings of sadness, loss of interest and easily tired. Steroids are drugs that can reduce swelling, pain and heat due to inflammation through reducing the immune response. Steroids are often used in cases of systemic Lupus Erythematosus in the long term. Therefore management of the disease must be done well because steroids can cause depression. Case Report:Women, 37 years old, depressed mood, disappointment in life, loss of enthusiasm, fatigue, decreased appetite and difficulty sleeping for 1 year. 4 years ago I took steroids for 2 years at a dose of 20mg / day, because rheumatoid arthritis was stopped by os, and for the past 1 year, steroid consumption was due to Systemic Lupus Erythematosus around 60 mg / day. . Before the os consumes steroids, the OS has never experienced depression.BP: 110/70 mmHg , HR 88x/menit, RR 20x/menit, Temp 37°C. Skor BDI 21. Laboratorium Hb 11,8 g/dl, Leukosit 7500/mm3, trombosit 201.000/mm3,,Kalium 2,8, KGDad 99 mg/dlSGOT 29 ,SGPT32, Ureum 15,78 mg/dl, Creatinin 0,65 mg/dl.  Tot Colesterol 198mg/dl,  LDL 128 mg/dl, HDL 35 mg/dl Fototoraks : Jantung dan Parudalambatas normal, FotoLumbosakral : SpondilosisLumbalis. The patient is diagnosed with depression. Given psychotherapy, sandepril 2 x 25 mg for 3 months. Patients show clinical improvement marked by reduced sadness and can understand the disease. Conclusion :Steroid-induced depression has been reported after psychotherapy and sandepril 2 x 25 mg of the patient's condition showed improvement.

Improvements in XCO2 accuracy from OCO-2 with the latest ACOS v10 product

2021 ◽  
Author(s):  
Christopher ODell ◽  
Annmarie Eldering ◽  
Michael Gunson ◽  
David Crisp ◽  
Brendan Fisher ◽  
...  
Keyword(s):  
Power Plants ◽  
Large Scale ◽  
Regional Scale ◽  
Surface Fluxes ◽  
Retrieval Algorithm ◽  
The Past ◽  
Tropical Oceans ◽  
Desert Areas ◽  
Global Carbon

<p>While initial plans for measuring carbon dioxide from space hoped for 1-2 ppm levels of accuracy (bias) and precision in the CO<sub>2</sub> column mean dry air mole fraction (XCO<sub>2</sub>), in the past few years it has become clear that accuracies better than 0.5 ppm are required for most current science applications.  These include measuring continental (1000+ km) and regional scale (100s of km) surface fluxes of CO<sub>2</sub> at monthly-average timescales.  Considering the 400+ ppm background, this translates to an accuracy of roughly 0.1%, an incredibly challenging target to hit. </p><p>Improvements in both instrument calibration and retrieval algorithms have led to significant improvements in satellite XCO<sub>2</sub> accuracies over the past decade.  The Atmospheric Carbon Observations from Space (ACOS) retrieval algorithm, including post-retrieval filtering and bias correction, has demonstrated unprecedented accuracy with our latest algorithm version as applied to the Orbiting Carbon Observatory-2 (OCO-2) satellite sensor.   This presentation will discuss the performance of the v10 XCO<sub>2</sub> product by comparisons to TCCON and models, and showcase its performance with some recent examples, from the potential to infer large-scale fluxes to its performance on individual power plants.  The v10 product yields better agreement with TCCON over land and ocean, plus reduced biases over tropical oceans and desert areas as compared to a median of multiple global carbon inversion models, allowing better accuracy and faith in inferred regional-scale fluxes.  More specifically, OCO-2 has single sounding precision of ~0.8 ppm over land and ~0.5 ppm over water, and RMS biases of 0.5-0.7 ppm over both land and water.  Given the six-year and growing length of the OCO-2 data record, this also enables new studies on carbon interannual variability, while at the same time allowing identification of more subtle and temporally-dependent errors.  Finally, we will discuss the prospects of future improvements in the next planned version (v11), and the long-term prospects of greenhouse gas retrievals in the coming years. </p><p> </p>

scholarly journals Was the Little Ice Age more or less El Niño-like than the Medieval Climate Anomaly? Evidence from hydrological and temperature proxy data

2017 ◽  
Vol 13 (3) ◽  
pp. 267-301 ◽  
Author(s):  
Lilo M. K. Henke ◽  
F. Hugo Lambert ◽  
Dan J. Charman
Keyword(s):  
Little Ice Age ◽  
Large Scale ◽  
Global Climate ◽  
Ice Age ◽  
Medieval Climate Anomaly ◽  
Climate Anomaly ◽  
Proxy Data ◽  
The Past ◽  
Proxy Records

Abstract. The El Niño–Southern Oscillation (ENSO) is the most important source of global climate variability on interannual timescales and has substantial environmental and socio-economic consequences. However, it is unclear how it interacts with large-scale climate states over longer (decadal to centennial) timescales. The instrumental ENSO record is too short for analysing long-term trends and variability and climate models are unable to accurately simulate past ENSO states. Proxy data are used to extend the record, but different proxy sources have produced dissimilar reconstructions of long-term ENSO-like climate change, with some evidence for a temperature–precipitation divergence in ENSO-like climate over the past millennium, in particular during the Medieval Climate Anomaly (MCA; AD  ∼  800–1300) and the Little Ice Age (LIA; AD  ∼  1400–1850). This throws into question the stability of the modern ENSO system and its links to the global climate, which has implications for future projections. Here we use a new statistical approach using weighting based on empirical orthogonal function (EOF) to create two new large-scale reconstructions of ENSO-like climate change derived independently from precipitation proxies and temperature proxies. The method is developed and validated using model-derived pseudo-proxy experiments that address the effects of proxy dating error, resolution, and noise to improve uncertainty estimations. We find no evidence that temperature and precipitation disagree over the ENSO-like state over the past millennium, but neither do they agree strongly. There is no statistically significant difference between the MCA and the LIA in either reconstruction. However, the temperature reconstruction suffers from a lack of high-quality proxy records located in ENSO-sensitive regions, which limits its ability to capture the large-scale ENSO signal. Further expansion of the palaeo-database and improvements to instrumental, satellite, and model representations of ENSO are needed to fully resolve the discrepancies found among proxy records and establish the long-term stability of this important mode of climatic variability.

Old trees as a key source of epiphytic lichen persistence and spatial distribution in mountain Norway spruce forests

2017 ◽  
Vol 26 (8) ◽  
pp. 1943-1958 ◽  
Author(s):  
Lucie Zemanová ◽  
Volodymyr Trotsiuk ◽  
Robert C. Morrissey ◽  
Radek Bače ◽  
Martin Mikoláš ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Norway Spruce ◽  
Epiphytic Lichen ◽  
Spruce Forests ◽  
Old Trees

Natural regeneration and vegetation changes in wet spruce forests after natural and artificial disturbances

2007 ◽  
Vol 37 (10) ◽  
pp. 1907-1914 ◽  
Author(s):  
Magda Jonášová ◽  
Ivona Matějková
Keyword(s):  
Norway Spruce ◽  
Bark Beetle ◽  
Natural Regeneration ◽  
Ips Typographus ◽  
Tree Regeneration ◽  
Vegetation Changes ◽  
Natural Disturbances ◽  
Spruce Forests ◽  
The Impact

An extensive area of Norway spruce ( Picea abies (L.) Karst.) forests in the Šumava Mountains, Central Europe, has been affected by a massive bark beetle ( Ips typographus L.) outbreak since the mid-1990s. One part of the area was left without intervention and two types of intervention have been applied in other parts: (1) the classical forest approach, based on the logging of attacked trees and (2) “sanitation”, in which attacked trees were cut down, debarked, and left lying in the stand. The main goal of our research was to test the impact of nonintervention and both types of intervention on the regeneration of the Norway spruce forests. The Norway spruce forests influenced by natural disturbances (bark beetle outbreak and windfalls) regenerated very well if left without intervention. The bark beetle outbreaks and windfalls do not represent a threat to the long-term persistence of the forests. Clearcuts resulted in formation of pioneer stages with a postponed spruce regeneration. In sanitation plots, the reduction of both previous vegetation and tree regeneration was obvious. Generally, both interventions against bark beetle delayed the recovery of Norway spruce forests.

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