The development of a simple basal area increment model

In most cases forest practice in Austria use yield tables to predict the growth of their forests. Common yield tables show the increment of pure even-aged stands which are treated in a way the table developer recommends. The usage of these tables in stands which are either uneven-aged, mixed or treated in another way, may lead to inaccurate predictions. To avoid these problems, forest growth models have been developed. Until now they are not widely used in Austria. One reason may be, that most of the models need some input parameters which are usually not gathered by companies. In this work a basal area increment per hectare model has been developed which is based on the input parameters: diameter at breast height, height to diameter ratio, top height at age 100 years and a selection out of several simple competition indices (growing space, basal area of larger trees, competing basal area, crown cross sectional area, crown competition factor, d/dg, d-dg, basal area and stand density index) which are distance independent. The model parametrization was done with seven different statistical methods (linear regression, linear mixed effect model, resistant linear regression, local polynomial regression, lazy learning model, random forest model and neural network model). By using only few input-parameters it should be possible to parametrize this model for many local areas by using inventory data sets of the specific region. The model works in pure and mixed stands of spruce and beech at the Rosaliengebirge. The observed average diameter increment per 5 years is 18.1 mm for spruce and 21.1 mm for beech. The average difference of the predicted and observed diameter-increment on a validation data-set is 0.3 mm for spruce and -0.3 mm for beech within 5 years and the estimated additional spread caused by the model is +-4.5 mm/5 years for spruce and +-4.0 mm/5 years for beech

Predicting the Deforestation–Trend Under Different Carbon–Prices

Background: Global carbon stocks in forest biomass are decreasing by 1.1 Gt of carbon annually, owing to continued deforestation and forest degradation. Deforestation emissions are partly offset by forest expansion and increases in growing stock primarily in the extra-tropical north. Innovative financial mechanisms would be required to help reducing deforestation. Using a spatially explicit integrated biophysical and socio-economic land use model we estimated the impact of carbon price incentive schemes and payment modalities on deforestation. One payment modality is adding costs for carbon emission, the other is to pay incentives for keeping the forest carbon stock intact. Results, Baseline scenario calculations show that close to 200mil ha or around 5% of today’s forest area will be lost between 2006 and 2025, resulting in a release of additional 17.5 GtC. Today’s forest cover will shrink by around 500 million hectares, which is 1/8 of the current forest cover, within the next 100 years. The accumulated carbon release during the next 100 years amounts to 45 GtC, which is 15% of the total carbon stored in forests today. Incentives of 6 US$/tC for the standing biomass paid every 5 years will bring deforestation down by 50$/year. On the other hand a carbon tax of 12$/tC harvested forest biomass will also cut deforestation by half. The tax income will decrease from 6 billion US$ in 2005 to 4.3 billion US$in 2025 and 0.7 billion US$ in 2100 due to decreasing deforestation speed. Conclusions, Avoiding deforestation requires financial mechanisms that make retention of forests economically competitive with the currently often preferred option to seek profits from other land uses. Incentive payments need to be at a very high level to be effective against deforestation. Taxes on the other hand will generate budgetary revenues by the regions which are already poor. A combination of incentives and taxes could turn out to be a viable solution for this dilemma. Increasing the value of forest land and thereby make it less easily prone to deforestation would act as a strong incentive to increase productivity of agricultural and fuelwood production, which could be supported by revenues generated by the deforestation tax.Deforestation, Carbon Prices

Agriculture, Population, Land and Water Scarcity in a Changing World – The Role of Irrigation

Fertile land and fresh water constitute two of the most fundamental resources for food production. These resources are affected by environmental, political, economic, and technical developments. Regional impacts may transmit to the world through increased trade. With a global forest and agricultural sector model, we quantify the impacts of increased demand for food due to population growth and economic development on potential land and water use. In particular, we investigate producer adaptation regarding crop and irrigation choice, agricultural market adjustments, and changes in the values of land and water.Irrigation, Food supply, Integrated assessment, Water use intensity, Agricultural adaptation, Land scarcity, Partial equilibrium model, Resource /Energy Economics and Policy,

Reference values for fatigued versus non-fatigued limb symmetry index measured by a newly designed single-leg hop test battery in healthy subjects : a pilot study

There is sparse evidence for return to sport criteria after knee injury. Functional performance deficits, particularly in fatigued muscular condition, should be verified prior to the attempt to return to high-risk pivoting sports. The purpose of this study was to generate reference values for the limb symmetry index (LSI) of healthy subjects in fatigued and non-fatigued muscular condition in a newly designed test battery

Clinical and radiological results after Internal Brace suture versus the all-inside reconstruction technique in anterior cruciate ligament tears 12 to 18 months after index surgery = Klinische und radiologische Ergebnisse nach Naht des vorderen Kreuzbandes mittels Internal-Brace- und All-inside-Kreuzbandersatzplastik nach 12–18 Monaten nach Operation

Background: Anterior cruciate ligament (ACL) injury can lead to reduced function, meniscal lesions, and early joint degeneration. Preservation of a torn ACL using the Internal Brace technique might re-establish normal knee kinematics, avoid donor-site morbidity due to tendon harvesting, and potentially maintain proprioception of the knee. Methods: Fifty subjects were recruited for this study between December 2015 and October 2016. Two groups of individuals who sustained a unilateral ACL rupture were included: those who underwent surgery with preservation of the injured ACL (Internal Brace technique; IB) and those who underwent ACL reconstruction using a hamstring tendon graft (all-inside technique; AI). Subjective self-administered scores were used: the German version of the IKDC Subjective Knee Form (International Knee Documentation Committee), the German version of the WOMAC (Western Ontario and McMaster Universities Arthritis Index), SF-36 (short form), the German version of the KOOS (Knee Osteoarthritis Outcome Score), and the German version of themodified Lysholm Score by Lysholm and Gillquist. Anterior tibial translation was assessed using the KT-1000 Arthrometer (KT-1000 Knee Ligament Arthrometer, MEDmetric Corp., San Diego, CA, USA). Magnetic resonance evaluation was performed in all cases. Results: Twenty-three subjects (46 %) were men, and the mean age was 34.7 years. The objective IKDC scores were "normal" in 15 and 14 patients, "nearly normal" in 11 and 7 patients, and "abnormal" in 1 and 2 patients, in the IB and AI groups, respectively. KT-1000 assessment showed a sideto-side difference of more than 3 mm on maximum manual testing in 11 (44 %) and 6 subjects (28.6 %) in the IB and AI groups, respectively. In the postoperative MRI, 20 (74 %) and 22 subjects (96 %) in the IB and AI groups had an intact ACL. Anterior tibial translation was significantly higher in the IB group compared with the AI group in the manual maximum test. Conclusions: Preservation of the native ACL with the Internal Brace primary repair technique can achieve comparable results to ACL reconstruction using Hamstring autografts over a short term. Clinically relevant limitations such as a higher incidence of pathologic laxity, with patients more prone to pivot-shift phenomenon were observed during the study period

The marker quantification of the Shared Socioeconomic Pathway 2: A middle-of-the-road scenario for the 21st century

AbstractStudies of global environmental change make extensive use of scenarios to explore how the future can evolve under a consistent set of assumptions. The recently developed Shared Socioeconomic Pathways (SSPs) create a framework for the study of climate-related scenario outcomes. Their five narratives span a wide range of worlds that vary in their challenges for climate change mitigation and adaptation. Here we provide background on the quantification that has been selected to serve as the reference, or ‘marker’, implementation for SSP2. The SSP2 narrative describes a middle-of-the-road development in the mitigation and adaptation challenges space. We explain how the narrative has been translated into quantitative assumptions in the IIASA Integrated Assessment Modelling Framework. We show that our SSP2 marker implementation occupies a central position for key metrics along the mitigation and adaptation challenge dimensions. For many dimensions the SSP2 marker implementation also reflects an extension of the historical experience, particularly in terms of carbon and energy intensity improvements in its baseline. This leads to a steady emissions increase over the 21st century, with projected end-of-century warming nearing 4°C relative to preindustrial levels. On the other hand, SSP2 also shows that global-mean temperature increase can be limited to below 2°C, pending stringent climate policies throughout the world. The added value of the SSP2 marker implementation for the wider scientific community is that it can serve as a starting point to further explore integrated solutions for achieving multiple societal objectives in light of the climate adaptation and mitigation challenges that society could face over the 21st century