scholarly journals Waldertrag und Anbaurisiko in einer unsicheren Klimazukunft

2016 ◽  
Vol 167 (1) ◽  
pp. 29-38 ◽  
Author(s):  
Christian Kölling ◽  
Tobias Mette ◽  
Thomas Knoke

Forest productivity and cultivation risk in an uncertain climate future Changes in climate conditions will lead to strong yet uncertain changes concerning forest growth and cultivation risk. Economic success as an important criterion for management decisions depends on both aspects, natural yield and risk. This study presents a new concept how (potential) yield and risk can be estimated from large-scale inventory data. As a result, any stand can be plotted in a yield-risk coordinate system and its future yield expectancy can be described by a trajectory in the yield-risk space. This strictly analytical approach cannot take over silvicultural decisions, but facilitates them from an objective basis. The implementation of approved economic guidelines such as the caution principle or the principle of flexibility builds upon the yield-risk approach and demonstrates benefits of climate-adapted stable mixed forest silviculture.

2017 ◽  
Vol 66 (1) ◽  
pp. 49-64 ◽  
Author(s):  
Mait Lang ◽  
Raimo Kõlli ◽  
Maris Nikopensius ◽  
Tiit Nilson ◽  
Mathias Neumann ◽  
...  

Abstract Optical remote sensing data-based estimates of terrestrial net primary production (NPP) are released by different projects using light use efficiency-type models. Although spatial resolution of the NPP data sets is still too coarse (500–1000 m) for single forest stands, regional monitoring of forest management and growth with 25–100 ha sampling units is feasible if the NPPSAT estimates are sensitive to forest growth differences depending on soil fertility in the area of interest. In this study, NPP estimates for 2,914 mixed forest class pixels (according to the MODIS land cover map) located in Estonia were (1) obtained from three different NPPSAT products, (2) calculated using an empirical soil potential phytoproductivity (SPP) model applied to a 1:10,000 soil map (NPPSPP), and (3) calculated using stem volume increment estimates given in a forest management inventory data base (NPPFIDB). A linear multiple regression model was then used to explore the relationships of NPPSAT with the proportion of coniferous forests, the NPPSPP and distance of the pixels from the Baltic Sea coast – the variables that have been found informative in previous studies. We found a positive moderate correlation (0.57, p < 0.001) between NPPSPP and NPPFIDB. The local or downscaled meteorological data-based NPPSAT estimates were more consistent with the NPPSPP and NPPFIDB, but the correlation with NPPSAT was weak and sometimes even negative. The range of NPP estimates in NPPSAT data sets was much narrower than the range of NPPSPP or NPPFIDB. Errors in land cover maps and in estimates of absorbed photosynthetically active radiation were identified as the main reasons for NPPSAT inconsistencies.


2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
Oskar Franklin ◽  
Elena Moltchanova ◽  
Florian Kraxner ◽  
Rupert Seidl ◽  
Hannes Böttcher ◽  
...  

While effects of thinning and natural disturbances on stand density play a central role for forest growth, their representation in large-scale studies is restricted by both model and data availability. Here a forest growth model was combined with a newly developed generic thinning model to estimate stand density and site productivity based on widely available inventory data (tree species, age class, volume, and increment). The combined model successfully coupled biomass, increment, and stand closure (=stand density/self-thinning limited stand density), as indicated by cross-validation against European-wide inventory data. The improvement in model performance attained by including variable stand closure among age cohorts compared to a fixed closure suggests that stand closure is an important parameter for accurate forest growth modeling also at large scales.


Author(s):  
Christoph Schwörer ◽  
Erika Gobet ◽  
Jacqueline F. N. van Leeuwen ◽  
Sarah Bögli ◽  
Rachel Imboden ◽  
...  

AbstractObserving natural vegetation dynamics over the entire Holocene is difficult in Central Europe, due to pervasive and increasing human disturbance since the Neolithic. One strategy to minimize this limitation is to select a study site in an area that is marginal for agricultural activity. Here, we present a new sediment record from Lake Svityaz in northwestern Ukraine. We have reconstructed regional and local vegetation and fire dynamics since the Late Glacial using pollen, spores, macrofossils and charcoal. Boreal forest composed of Pinus sylvestris and Betula with continental Larix decidua and Pinus cembra established in the region around 13,450 cal bp, replacing an open, steppic landscape. The first temperate tree to expand was Ulmus at 11,800 cal bp, followed by Quercus, Fraxinus excelsior, Tilia and Corylus ca. 1,000 years later. Fire activity was highest during the Early Holocene, when summer solar insolation reached its maximum. Carpinus betulus and Fagus sylvatica established at ca. 6,000 cal bp, coinciding with the first indicators of agricultural activity in the region and a transient climatic shift to cooler and moister conditions. Human impact on the vegetation remained initially very low, only increasing during the Bronze Age, at ca. 3,400 cal bp. Large-scale forest openings and the establishment of the present-day cultural landscape occurred only during the past 500 years. The persistence of highly diverse mixed forest under absent or low anthropogenic disturbance until the Early Middle Ages corroborates the role of human impact in the impoverishment of temperate forests elsewhere in Central Europe. The preservation or reestablishment of such diverse forests may mitigate future climate change impacts, specifically by lowering fire risk under warmer and drier conditions.


Author(s):  
Kirsten Höwler ◽  
Torsten Vor ◽  
Peter Schall ◽  
Peter Annighöfer ◽  
Dominik Seidel ◽  
...  

AbstractResearch on mixed forests has mostly focused on tree growth and productivity, or resistance and resilience in changing climate conditions, but only rarely on the effects of tree species mixing on timber quality. In particular, it is still unclear whether the numerous positive effects of mixed forests on productivity and stability come at the expense of timber quality. In this study, we used photographs of sawn boards from 90 European beech (Fagus sylvatica L.) trees of mixed and pure forest stands to analyze internal timber quality through the quality indicator knot surface that was quantitatively assessed using the software Datinf® Measure. We observed a decrease in knot surface with increasing distance from the pith as well as smaller values in the lower log sections. Regarding the influence of neighborhood species identity, we found only minor effects meaning that timber qualities in mixed stands of beech and Norway spruce (Picea abies (L.) H. Karst.) tended to be slightly worse compared to pure beech stands.


2014 ◽  
Vol 5 (1) ◽  
Author(s):  
Heru Kuswantoro

Most of Indonesia dryland is covered by acid soil which lead to the decreasing potential yield of the crops. In different areas soybean potential yield also different depends on the different soil pH and the availability of the soil. The objective of the research was to study the potential yield of soybean promising lines in acid soil of Central Lampung, Indonesia. Ten promising lines and two check varieties (Tanggamus and Wilis) were grown in acid soil with pH 4.7. The results showed that the highest seed yield was showed by SC5P2P3.5.4.1-5 with 2.51 t/ha. Other soybean promising lines with seed yield over than 2 t/ha-1 was SJ-5/Msr.99.5.4.5-1-6-1 and the check variety Tanggamus. The highest yield of SC5P2P3.5.4.1-5 was caused by the high number of filled pods and the large of seed size. Other nine promising lines also can be developed to obtained grain yield as many as Tanggamus yield in the area with similar soil and climate conditions.


Author(s):  
S.V. Emelina ◽  
◽  
V.M. Khan ◽  

The possibility of developing specialized seasonal forecasting within the framework of the North Eurasia Climate Centre is discussed. The purpose of these forecasts is to access the impacts of significant large-scale anomalies of meteorological elements on various economic sectors for the timely informing of government services and private businesses to select optimal strategies for planning preventive measures. A brief overview of the groups of climatic risks in the context of the impacts on the socio-economic sphere is given according to the Russian and foreign bibliographic sources. Examples of the activities of some Regional Climate Centers that produce forecast information with an assessment of possible impacts of weather and climate conditions at seasonal scales on various human activities are given. Keywords: climate services, regional climate forums, weather and climate risks, North Eurasia Climate Centre


2021 ◽  
Author(s):  
Alice Crespi ◽  
Marcello Petitta ◽  
Lucas Grigis ◽  
Paola Marson ◽  
Jean-Michel Soubeyroux ◽  
...  

&lt;p&gt;Seasonal forecasts provide information on climate conditions several months ahead and therefore they could represent a valuable support for decision making, warning systems as well as for the optimization of industry and energy sectors. However, forecast systems can be affected by systematic biases and have horizontal resolutions which are typically coarser than the spatial scales of the practical applications. For this reason, the reliability of forecasts needs to be carefully assessed before applying and interpreting them for specific applications. In addition, the use of post-processing approaches is recommended in order to improve the representativeness of the large-scale predictions of regional and local climate conditions. The development and evaluation downscaling and bias-correction procedures aiming at improving the skills of the forecasts and the quality of derived climate services is currently an open research field. In this context, we evaluated the skills of ECMWF SEAS5 forecasts of monthly mean temperature, total precipitation and wind speed over Europe and we assessed the skill improvements of calibrated predictions.&lt;/p&gt;&lt;p&gt;For the calibration, we combined a bilinear interpolation and a quantile mapping approach to obtain corrected monthly forecasts on a 0.25&amp;#176;x0.25&amp;#176; grid from the original 1&amp;#176;x1&amp;#176; values. The forecasts were corrected against the reference ERA5 reanalysis over the hindcast period 1993&amp;#8211;2016. The processed forecasts were compared over the same domain and period with another calibrated set of ECMWF SEAS5 forecasts obtained by the ADAMONT statistical method.&lt;/p&gt;&lt;p&gt;The skill assessment was performed by means of both deterministic and probabilistic verification metrics evaluated over seasonal forecasted aggregations for the first lead time. Greater skills of the forecast systems in Europe were generally observed in spring and summer, especially for temperature, with a spatial distribution varying with the seasons. The calibration was proved to effectively correct the model biases for all variables, however the metrics not accounting for bias did not show significant improvements in most cases, and in some areas and seasons even small degradations in skills were observed.&lt;/p&gt;&lt;p&gt;The presented study supported the activities of the H2020 European project SECLI-FIRM on the improvement of the seasonal forecast applicability for energy production, management and assessment.&lt;/p&gt;


2018 ◽  
Vol 23 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Zar Chi Win ◽  
Nobuya Mizoue ◽  
Tetsuji Ota ◽  
Tsuyoshi Kajisa ◽  
Shigejiro Yoshida ◽  
...  

2021 ◽  
Author(s):  
Iñigo Gómara ◽  
Belén Rodríguez-Fonseca ◽  
Elsa Mohino ◽  
Teresa Losada ◽  
Irene Polo ◽  
...  

AbstractTropical Pacific upwelling-dependent ecosystems are the most productive and variable worldwide, mainly due to the influence of El Niño Southern Oscillation (ENSO). ENSO can be forecasted seasons ahead thanks to assorted climate precursors (local-Pacific processes, pantropical interactions). However, owing to observational data scarcity and bias-related issues in earth system models, little is known about the importance of these precursors for marine ecosystem prediction. With recently released reanalysis-nudged global marine ecosystem simulations, these constraints can be sidestepped, allowing full examination of tropical Pacific ecosystem predictability. By complementing historical fishing records with marine ecosystem model data, we show herein that equatorial Atlantic Sea Surface Temperatures (SSTs) constitute a superlative predictability source for tropical Pacific marine yields, which can be forecasted over large-scale areas up to 2 years in advance. A detailed physical-biological mechanism is proposed whereby Atlantic SSTs modulate upwelling of nutrient-rich waters in the tropical Pacific, leading to a bottom-up propagation of the climate-related signal across the marine food web. Our results represent historical and near-future climate conditions and provide a useful springboard for implementing a marine ecosystem prediction system in the tropical Pacific.


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