scholarly journals Long-Term Abandonment of Forest Management Has a Strong Impact on Tree Morphology and Wood Volume Allocation Pattern of European Beech (Fagus Sylvatica L.)

Forests ◽  
2018 ◽  
Vol 9 (11) ◽  
pp. 704 ◽  
Author(s):  
Louis Georgi ◽  
Matthias Kunz ◽  
Andreas Fichtner ◽  
Werner Härdtle ◽  
Karl Reich ◽  
...  
Keyword(s):  
Forest Management ◽  
High Resolution ◽  
Morphological Traits ◽  
Short Term ◽  
Wood Volume ◽  
Management Intensity ◽  
Fagus Sylvatica L ◽  
Intensively Managed ◽  
The Vertical Distribution

The three-dimensional (3D) morphology of individual trees is critical for light interception, growth, stability and interactions with the local environment. Forest management intensity is a key driver of tree morphology, but how the long-term abandonment of silvicultural measures impacts trunk and crown morphological traits is not fully understood. Here, we take advantage of a long management intensity gradient combined with a high-resolution terrestrial laser scanning (TLS) approach to explore how management history affects the 3D structure of mature beech (Fagus sylvatica L.) trees. The management gradient ranged from long-term (>50 years) and short-term (>20 years) unmanaged to extensively and intensively managed beech stands. We determined 28 morphological traits and quantified the vertical distribution of wood volume along the trunk. We evaluated the differences in tree morphological traits between study stands using Tukey’s HSD test. Our results show that 93% of the investigated morphological traits differed significantly between the study stands. Significant differences, however, emerged most strongly in the stand where forest management had ceased >50 years ago. Furthermore, we found that the vertical distribution of trunk wood volume was highly responsive between stands with different management intensity, leading to a 67% higher taper top height and 30% lower taper of beech trees growing in long-term unmanaged stands compared to those in short-term unmanaged or managed stands. These results have important implications for management intensity decisions. It is suggested that the economic value of individual beech trees from long-term unmanaged forests can be expected to be very high. This might also translate to beech forests that are extensively managed, but we found that a few decades of implementation of such a silvicultural system is not sufficient to cause significant differences when compared to intensively managed stands. Furthermore, TLS-based high-resolution analyses of trunk and crown traits play a crucial role in the ability to better understand or predict tree growth responses to the current drivers of global change.

Evaluation of forest management strategies based on Triad zoning

2015 ◽  
Vol 91 (01) ◽  
pp. 40-51 ◽  
Author(s):  
Chris Ward ◽  
Thom Erdle
Keyword(s):  
Forest Management ◽  
Social Economic ◽  
Management Strategies ◽  
Short Term ◽  
Timber Supply ◽  
Timing Offset ◽  
Intensively Managed ◽  
Selling Point ◽  
Forecast Time

Triad forest management was analyzed for a New Brunswick Crown License. Fifteen forest value indicators were used to describe social, economic, and environmental outcomes from forecast Triad scenarios, including 36 scenarios where reserves and intensively managed area varied in 5% increments from 10% to 35%. Some indicators were most sensitive to intensive area (e.g., silviculture cost), other to reserve area (e.g., area containing large snags), and still others to extensive area (e.g., average harvest levels). Some indicators averaged arithmetically, and could be kept constant if increases in reserves were accompanied by equal increases in intensive area. Such averaging for timber supply is often a selling point made by Triad advocates. Indeed, many different scenarios generated the same annual harvest when averaged over the 100-year forecast time horizon; however, immediate reductions in operable timber inventory resulting from reserve increases caused short-term harvest reductions, while future gains in yield from intensive area increases caused long-term harvest increases. This timing offset between losses and gains of operable volume, and its effect on harvest timing, may be impediments to Triad implementation in jurisdictions where timber supply is fully utilized. This analysis presents methods and results that may be of value to forest managers contemplating implementation of Triad zoning.

scholarly journals The Long-term Variation in the RV Tauri Star U Mon

1995 ◽  
Vol 155 ◽  
pp. 409-410 ◽  
Author(s):  
Karen R. Pollard ◽  
P. L. Cottrell
Keyword(s):  
High Resolution ◽  
Light Curve ◽  
Radial Velocity ◽  
Tauri Star ◽  
Short Term ◽  
Instability Strip ◽  
Term Variation ◽  
Velocity Variations

The RV Tauri stars are semiregular pulsating variables located in the brightest part of the Cepheid II instability strip. They have a characteristic light curve of alternating deep and shallow minima. A subset of the RV Tauri stars (the RVb subclass) exhibit long-term (500 to 2600 day) light and radial velocity variations. Although it is well established that the short-term variations are due to pulsations, the long-term behaviour is not well understood.BVRI photometry and high-resolution spectra of U Mon (the brightest member of the RVb subclass) were obtained at the Mt John University Observatory (MJUO) between 1990 Aug and 1994 May. The light and colour curves obtained clearly show the long-term variation in U Mon (Fig. 1(a) and (b)). The reddest colours occur slightly later than the long-term minimum in the light curve. The short-term light and colour variations are ‘damped’ at the long-term minimum.

Coastal climatology of the North-Western Mediterranean area for long-term and short-term risk assessment.

2020 ◽  
Author(s):  
Carlo Brandini ◽  
Stefano Taddei ◽  
Valentina Vannucchi ◽  
Michele Bendoni ◽  
Bartolomeo Doronzo ◽  
...  
Keyword(s):  
Risk Assessment ◽  
High Resolution ◽  
Mediterranean Area ◽  
Western Mediterranean ◽  
Climate Trends ◽  
Short Term ◽  
The North ◽  
The Mediterranean ◽  
North Western

<p>In this work we present the results obtained through a dynamic downscaling of the ERA5 reanalysis dataset (hindcast) of ECMWF, using high-resolution meteorological and wave models defined on unstructured computation grids along the Mediterranean coasts, with a particular focus on the North-Western Mediterranean area. Downscaling of the ERA5 meteorological data is obtained through the BOLAM and MOLOCH models (up to a resolution of 2.5 km) which force an unstructured WW3 model with a resolution of up to 500 m along the coast. Models were validated through available meteorological stations, wave buoy data and X-band wave radars, the latter for the purposes of wave spectra validation.</p><p>On the one hand, this allowed, by extracting the time series of some attack parameters of the waves along the coast, and according to the type of coast (rocky coasts, sandy coasts, coastal structures etc.), to compute the return periods and to characterize the impact of any individual storm. On the other hand, it is possible to highlight some trends observed in the last 30 years, during which recent research is showing an increasing evidence  of some changes in global circulation at regional to local scales. These changes also include effects of wind rotation, wave regimes, storm surges, wave-induced coastal currents and coastal morphodynamics. For example, in the North-Western Mediterranean extreme events belonging to cyclonic weather-types circulation with stronger S-SE components (like the storm of October 28-30th 2018 and many others), rather than events associated with perturbations of Atlantic origin and zonal circulation, are becoming more frequent. These long-term wind/wave climate trends can have consequences not only in the assessment of long-term risk due to main morphodynamic variations (ie. coastal erosion), but also in the short-term risk assessment.</p><p>This work was funded by the EU MAREGOT project (2017-2020) and ECMWF Special Project spitbran  “Evaluation of coastal climate trends in the Mediterranean area by means of high-resolution and multi-model downscaling of ERA5 reanalysis” (2018-2020).</p>

scholarly journals On the Identification and Characterization of Drought and Aridity in Postglacial Paleoenvironmental Records from the Northern Great Plains

2004 ◽  
Vol 56 (2-3) ◽  
pp. 229-246 ◽  
Author(s):  
Alwynne B. Beaudoin
Keyword(s):  
Global Warming ◽  
High Resolution ◽  
Great Plains ◽  
Northern Great Plains ◽  
Short Term ◽  
Instrumental Data ◽  
Proxy Records ◽  
Identification And Characterization

Abstract The Northern Great Plains region is especially sensitive to drought and is likely to be even more drought-prone under projected global warming. Drought has been invoked as an explanatory factor for changes seen in postglacial paleoenvironmental records. These proxy records may extend drought history derived from instrumental data. Moreover, in the last decade, some paleoenvironmental studies have been expressly undertaken for the examination of long-term drought history. Nevertheless, few such studies explicitly define drought. This makes it difficult to compare results or to understand what the results mean in terms of the operational drought definitions that are used in resource management. Operational drought is defined as usually short-term; longer sustained dry intervals reflect a shift to aridity. Therefore, high resolution paleoenvironmental proxies (annual or subdecadal) are best for the investigation of drought history. Such proxies include tree rings and some lake records. However, most lake-based records are sampled at lower resolution (decadal or subcentury) and are therefore providing aridity signals.

High-resolution records of the response of coastal wetland systems to long-term and short-term sea-level variability

2009 ◽  
Vol 84 (4) ◽  
pp. 493-508 ◽  
Author(s):  
Alexander S. Kolker ◽  
Steven L. Goodbred ◽  
Sultan Hameed ◽  
J. Kirk Cochran
Keyword(s):  
High Resolution ◽  
Sea Level ◽  
Coastal Wetland ◽  
Short Term ◽  
Sea Level Variability

scholarly journals Species associations and management intensity modulate the habitat niche breadth of forest birds

2020 ◽  
Author(s):  
Marco Basile ◽  
Thomas Asbeck ◽  
João M. Cordeiro Pereira ◽  
Grzegorz Mikusiński ◽  
Ilse Storch
Keyword(s):  
Forest Management ◽  
Niche Breadth ◽  
Community Organization ◽  
Species Abundance ◽  
Local Effect ◽  
Landscape Context ◽  
Niche Modelling ◽  
Habitat Niche ◽  
Management Intensity ◽  
Intensively Managed

AbstractSpecies associations can have profound effects on the realized habitat niche of species, indicating that habitat structure alone cannot fully explain observed abundances. To account for this aspect of community organization in niche modelling, we developed multi-species abundance models, incorporating the local effect of potentially associated species, alongside with environmental ones, targeting mainly forest management intensity. We coupled it with a landscape-scale analysis to further examine the role of management intensity in modifying the habitat niche in connection with the landscape context. Using empirical data from the Black Forest in southern Germany, we focused on the forest bird assemblage and in particular on the cavity nester and canopy forager guilds. We included in the analysis species that co-occur and for which evidences suggest association is likely. Our findings show that the local effect of species associations can moderate the effects of management intensity. We also found that species express a larger habitat niche breadth in intensively managed forests, depending on the landscape context. Species associations may facilitate the utilization of a broader range of environmental conditions under intensive forest management, which benefits some species over others. Such network of associations may be a relevant factor in the effectiveness of conservation-oriented forest management.

The Research of High-Resolution Sequence Stratigraphy of Putaohua Reservoir in Daan Oilfield

2013 ◽  
Vol 838-841 ◽  
pp. 1843-1846
Author(s):  
Ting Ting Li ◽  
Yue Shi ◽  
You Hai Sun ◽  
Ming Qin
Keyword(s):  
High Resolution ◽  
Sequence Stratigraphy ◽  
Geophysical Data ◽  
Short Term ◽  
Middle Term ◽  
Sequence Stratigraphic ◽  
Stratigraphic Framework ◽  
Basic Characteristics ◽  
High Resolution Sequence Stratigraphy

By using geological and geophysical data and according to the basic characteristics of sequence boundary, Putaohua Reservoir in Daan Oilfield is divided into a rise hemicycle in long-term cycles, a full middle-term cycle, nine short-term cycles and a number of ultra-short-term cycles.The high-resolution sequence stratigraphic framework of Putaohua reservoir under monosandbody rank is established, and a set of techniques and methods to high-resolution sequence stratigraphy correlation in shallow delta is summed up.

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