@article{RoellRameshaLinketal.2021, author = {R{\"o}ll, Alexander and Ramesha, Mundre N. and Link, Roman M. and Hertel, Dietrich and Schuldt, Bernhard and Patil, Shekhargouda L. and H{\"o}lscher, Dirk}, title = {Water availability controls the biomass increment of Melia dubia in South India}, series = {Forests}, volume = {12}, journal = {Forests}, number = {12}, issn = {1999-4907}, doi = {10.3390/f12121675}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-250150}, year = {2021}, abstract = {Farmland tree cultivation is considered an important option for enhancing wood production. In South India, the native leaf-deciduous tree species Melia dubia is popular for short-rotation plantations. Across a rainfall gradient from 420 to 2170 mm year\(^{-1}\), we studied 186 farmland woodlots between one and nine years in age. The objectives were to identify the main factors controlling aboveground biomass (AGB) and growth rates. A power-law growth model predicts an average stand-level AGB of 93.8 Mg ha\(^{-1}\) for nine-year-old woodlots. The resulting average annual AGB increment over the length of the rotation cycle is 10.4 Mg ha\(^{-1}\) year\(^{-1}\), which falls within the range reported for other tropical tree plantations. When expressing the parameters of the growth model as functions of management, climate and soil variables, it explains 65\% of the variance in AGB. The results indicate that water availability is the main driver of the growth of M. dubia. Compared to the effects of water availability, the effects of soil nutrients are 26\% to 60\% smaller. We conclude that because of its high biomass accumulation rates in farm forestry, M. dubia is a promising candidate for short-rotation plantations in South India and beyond.}, language = {en} } @article{EllsaesserRoellAhongshangbametal.2020, author = {Ells{\"a}ßer, Florian and R{\"o}ll, Alexander and Ahongshangbam, Joyson and Waite, Pierre-Andr{\´e} and Hendrayanto, and Schuldt, Bernhard and H{\"o}lscher, Dirk}, title = {Predicting tree sap flux and stomatal conductance from drone-recorded surface temperatures in a mixed agroforestry system — a machine learning approach}, series = {Remote Sensing}, volume = {12}, journal = {Remote Sensing}, number = {24}, issn = {2072-4292}, doi = {10.3390/rs12244070}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220059}, year = {2020}, abstract = {Plant transpiration is a key element in the hydrological cycle. Widely used methods for its assessment comprise sap flux techniques for whole-plant transpiration and porometry for leaf stomatal conductance. Recently emerging approaches based on surface temperatures and a wide range of machine learning techniques offer new possibilities to quantify transpiration. The focus of this study was to predict sap flux and leaf stomatal conductance based on drone-recorded and meteorological data and compare these predictions with in-situ measured transpiration. To build the prediction models, we applied classical statistical approaches and machine learning algorithms. The field work was conducted in an oil palm agroforest in lowland Sumatra. Random forest predictions yielded the highest congruence with measured sap flux (r\(^2\) = 0.87 for trees and r\(^2\) = 0.58 for palms) and confidence intervals for intercept and slope of a Passing-Bablok regression suggest interchangeability of the methods. Differences in model performance are indicated when predicting different tree species. Predictions for stomatal conductance were less congruent for all prediction methods, likely due to spatial and temporal offsets of the measurements. Overall, the applied drone and modelling scheme predicts whole-plant transpiration with high accuracy. We conclude that there is large potential in machine learning approaches for ecological applications such as predicting transpiration.}, language = {en} } @article{PinkawaAebersoldBoehmeretal.2021, author = {Pinkawa, Michael and Aebersold, Daniel M. and B{\"o}hmer, Dirk and Flentje, Michael and Ghadjar, Pirus and Schmidt-Hegemann, Nina-Sophie and H{\"o}cht, Stefan and H{\"o}lscher, Tobias and M{\"u}ller, Arndt-Christian and Niehoff, Peter and Sedlmayer, Felix and Wolf, Frank and Zamboglou, Constantinos and Zips, Daniel and Wiegel, Thomas}, title = {Radiotherapy in nodal oligorecurrent prostate cancer}, series = {Strahlentherapie und Onkologie}, volume = {197}, journal = {Strahlentherapie und Onkologie}, number = {7}, issn = {0179-7158}, doi = {10.1007/s00066-021-01778-1}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-307763}, pages = {575-580}, year = {2021}, abstract = {Objective The current article encompasses a literature review and recommendations for radiotherapy in nodal oligorecurrent prostate cancer. Materials and methods A literature review focused on studies comparing metastasis-directed stereotactic ablative radiotherapy (SABR) vs. external elective nodal radiotherapy (ENRT) and studies analyzing recurrence patterns after local nodal treatment was performed. The DEGRO Prostate Cancer Expert Panel discussed the results and developed treatment recommendations. Results Metastasis-directed radiotherapy results in high local control (often > 90\% within a follow-up of 1-2 years) and can be used to improve progression-free survival or defer androgen deprivation therapy (ADT) according to prospective randomized phase II data. Distant progression after involved-node SABR only occurs within a few months in the majority of patients. ENRT improves metastases-free survival rates with increased toxicity in comparison to SABR according to retrospective comparative studies. The majority of nodal recurrences after initial local treatment of pelvic nodal metastasis are detected within the true pelvis and common iliac vessels. Conclusion ENRT with or without a boost should be preferred to SABR in pelvic nodal recurrences. In oligometastatic prostate cancer with distant (extrapelvic) nodal recurrences, SABR alone can be performed in selected cases. Application of additional systemic treatments should be based on current guidelines, with ADT as first-line treatment for hormone-sensitive prostate cancer. Only in carefully selected patients can radiotherapy be initially used without additional ADT outside of the current standard recommendations. Results of (randomized) prospective studies are needed for definitive recommendations.}, language = {en} }