First results of a GNSS-R experiment from a stratospheric balloon over boreal forests

The empirical results of a global navigation satellite systems reflectometry (GNSS-R) experiment onboard the Balloon EXperiments for University Students (BEXUS) 17 stratospheric balloon performed north of Sweden over boreal forests show that the power of the reflected signals is nearly independent of the platform height for a high coherent integration time T-c = 20 ms. This experimental evidence shows a strong coherent component in the forward scattered signal, as compared with the incoherent component, that allows to be tracked. The bistatic coherent reflectivity is also evaluated as a function of the elevation angle, showing a decrease of similar to 6 dB when the elevation angle increases from 35. to 70 degrees. The received power presents a clearly multimodal behavior, which also suggests that the coherent scattering component may be taking place in different forest elements, i.e., soil, canopy, and through multiple reflections canopy-soil and soil-trunk. This experiment has provided the first GNSS-R data set over boreal forests. The evaluation of these results can be useful for the feasibility study of this technique to perform biomass monitoring that is a key factor to analyze the carbon cycle.Peer ReviewedPostprint (author's final draft

Quantile contours and allometric modelling for risk classification of abnormal ratios with an application to asymmetric growth-restriction in preterm infants

We develop an approach to risk classification based on quantile contours and allometric modelling of multivariate anthropometric measurements. We propose the definition of allometric direction tangent to the directional quantile envelope, which divides ratios of measurements into half-spaces. This in turn provides an operational definition of directional quantile that can be used as cutoff for risk assessment. We show the application of the proposed approach using a large dataset from the Vermont Oxford Network containing observations of birthweight (BW) and head circumference (HC) for more than 150,000 preterm infants. Our analysis suggests that disproportionately growth-restricted infants with a larger HC-to-BW ratio are at increased mortality risk as compared to proportionately growth-restricted infants. The role of maternal hypertension is also investigated.Comment: 31 pages, 3 figures, 8 table

Destructive technologies as driving forces of new technological cycles for industrial and corporate change

Abstract. This study suggests a new concept of technology that is a main element of the system of technological change in society: killer or disruptive technology is a based on new products and/or processes that destroys the usage of established products/processes sold and used. The behavior of killer technologies is operationalized here with a simple model that shows how new technologies substitute old ones. technologies. Several examples illustrate this vital concept for economics of technology that can explain the drivers of technological cycles and technological change in society.  Empirical evidence of this theoretical framework is based on data of some example technologies. Theoretical framework and empirical evidence hint at general properties of the behavior of killer technologies: a) killer technology is always associated with some comparable established technology in markets; b) killer technology has a disproportionate growth in relation to victim technology; c) in the long run, killer technology has a series of technological advances of its own resulting from various major and minor innovations to pave the way for the dominance over other established technologies in markets; d) learning via diffusion and diffusion by learning are driving forces  underlying the development and adoption of killer technology in turbulent markets. The proposed theoretical framework can explain industrial, economic and social change and support strategies of management of technology for competitive advantage of firms and nations.Keywords. Killer technology, Diffusion of innovation; Radical innovation, Destructive creation, Evolution of technology, Development of technology, Technological cycles, Dynamics of technological innovation, Technology change, Management of technology, Allometric process, Learning processes.JEL. O30, O32, O33, B50

Chemical Composition of the Eggs of the Freshwater Turtle Phrynops hilarii (Chelidae: Testudines)

At oviposition, amniote eggs contain all the nutrients required for complete neonate tissue development. For reptiles and birds, the egg yolk is the main embryonic energy source and is composed predominantly of proteins and lipids, while also providing essential inorganic ions including calcium (Ca), potassium (K), and magnesium (Mg), and trace elements such as zinc (Z) and iron (Fe). Despite the fact that the Hilaire’s Toadhead Turtle, Phrynops hilarii, is one of the most representative and widely distributed turtle species in Argentina, there are very few studies regarding its reproductive biology. The objectives of this work were to (1) describe the morphological characteristics of Phrynops hilarii eggs, specifically egg and yolk size; (2) determine the relative proportions of egg yolk components (water, ash, lipids, proteins, and minerals); and (3) examine the relationships between egg size, yolk size and yolk components. We collected 171 eggs from 11 individual nests during the 2012 March-April reproductive season. We analyzed one egg per clutch (n = 11) to determine the egg yolk chemical composition. Yolks were composed of 58.3% water, while the dry component was 2.7% ash, 24.9% lipids, and 56.7% protein. The most abundant macromineral detected was K (0.63%) and the most abundant trace mineral was Mg (0.13%). We did not find associations between egg measurements and components, but there were many significant correlations between egg components. Data we collected for this study are important to begin to understand the roles of different nutrients in embryonic development and to further explore maternal investment patterns in Phrynops hilarii.En el momento de la oviposición los huevos amniotas contienen todos los nutrientes necesarios para el desarrollo completo del tejido neonatal. Para reptiles y aves, la yema del huevo es la principal fuente de energía embrionaria y está compuesta predominantemente de proteínas y lípidos y además proporciona iones inorgánicos esenciales que incluyen calcio (Ca), potasio (K) y magnesio (Mg) y trazas de oligoelementos como zinc (Z) y hierro (Fe). A pesar de que Phrynops hilarii es una de las especies de tortugas más representativas y ampliamente distribuidas de Argentina, existen muy pocos estudios sobre su biología reproductiva. Los objetivos de este trabajo fueron (1) describir las características morfológicas de los huevos de Phrynops hilarii, específicamente el tamaño del huevo y la yema; (2) determinar las proporciones relativas de los componentes de la yema de huevo (humedad, ceniza, lípidos, proteínas y minerales); y (3) examinar las relaciones entre el tamaño del huevo, el tamaño de la yema y los componentes de la yema. Recolectamos 171 huevos de 11 nidos individuales durante la temporada reproductiva de marzo a abril de 2012. Analizamos un huevo por nidada (n = 11) para determinar la composición química de la yema de huevo. Las yemas presentaron un 58,3% de humedad, mientras que el componente seco fue un 2,7% de ceniza, un 24,9% de lípidos y un 56,7% de proteína. El macromineral más abundante detectado fue K (0,63%) y el oligoelemento más abundante fue Mg (0,13%). No encontramos asociaciones entre las mediciones y los componentes del huevo, pero hubo muchas correlaciones significativas entre los componentes del huevo. Los datos que recopilamos para este estudio son importantes para comenzar a comprender los roles de los diferentes nutrientes en el desarrollo embrionario y para explorar más a fondo los patrones de inversión materna en Phrynops hilarii.Fil: Prieto, Yanina. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; ArgentinaFil: Bernardi, Cecilia Gabriela. Universidad Nacional del Litoral. Facultad de Ingeniería Química; ArgentinaFil: Rozycki, Víctor Rodolfo. Universidad Nacional del Litoral. Facultad de Ingeniería Química; ArgentinaFil: Manzano, Adriana Silvina. Universidad Autónoma de Entre Ríos; Argentina. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; Argentin

Integrating Remote Sensing Techniques into Forest Monitoring: Selected Topics with a Focus on Thermal Remote Sensing

A sustainable management of natural resources, in particular of forests, is of great importance to preserve the ecological, environmental and economic benefits of forests for future generations. An enhanced understanding of the current situation and ongoing trends of forests, e.g. through policy interventions, is crucial to managing the forest wisely. In this context, forest monitoring is essential for collecting the base data required and for observing trends. Despite the wide range of approved methods and techniques for both close-range and satellite-based remote sensing monitoring, ongoing forest monitoring research is still grappling with specific and unresolved questions: The data acquired must be more reliable, in particular over a long-term period; costs need to be reduced through advancements in both methods and technology that offer easier and more feasible ways of interpreting data. This thesis comprises a number of focused studies, each with their individual and specific research questions, and aims to explore the benefits of innovative methods and technologies. The main emphasis of the studies presented is the integration of close-range and satellite-based remote sensing for enhancing the efficiency of forest monitoring. Manuscript I discusses thermal canopy photography, a new field of application. This approach takes advantage of the large differences in temperature between sky and non-sky pixels and overcomes the inconsistencies of finding an optimal threshold. For an unambiguously separation of “sky” and “non-sky” pixels, a global threshold of 0 °C was defined. Currently, optical or hemispherical canopy photography is the most widely used method to extract crown-related variables. However, a number of aspects, such as exposure, illumination conditions, and threshold definition present a challenge in optical canopy photography and dramatically influence the result; consequently, a comparison of the results from optical canopy photography at a different point in time derived is not advisable. For forest monitoring, where repeated measurements of the canopy cover on the same plots were undertaken, it is therefore of utmost importance to devise a standard protocol to estimate changes in and compare the canopy covers. This paper offers such a protocol by introducing thermal canopy photography. A feasible and accurate method that examines the strong correlation (R2 = 0.96) of canopy closure values derived from thermal and optical image pairs. Thermal photography, as a close-range remote sensing technique, also aids data collection and analysis in other contexts, for instance to expand our knowledge about bamboo tree species: Information about the maturity of bamboo culms is of utmost importance for managing bamboo stands because only then the process of lignification is finished and the culm is technically stronger and more resistant to insect and fungi attacks. The findings of a study (Manuscript III) conducted in Pereira, Colombia, show small differences in culm surface temperature between culms of different ages for the bamboo species Guadua angustifolia K., which may be a sign of maturity. The surface temperature of 12 culms was measured after sunrise using the thermal camera system FLIR 60Ebx. This study shows an innovative close-range remote sensing technique which may support researchers’ determination of the maturity of bamboo culms. This research is in its inception phase and our results are the first of this kind. In the context of analyzing, in particular of thermal imagery time-series data, Manuscript (IV) offers a new methodology using advanced statistical methods. Otsu Thresholding, an automatic segmentation technique is used in a first processing step. O’Sullivan penalized splines estimated the temperature profile extracted from the canopy leaf temperature. A final comparison of the different profiles is done by constructing simultaneous confidence bands. The result shows an approximately significant difference in canopy leaf temperature. For this study, we successfully cooperated with the Center for Statistics at Göttingen University (Prof. Kneib). The second close-range remote sensing technology employed in this thesis is terrestrial laser scanning which is used here to enhance our understanding about buttressed trees. Big trees with an irregular non-convex shape are important contributors to aboveground biomass in tropical forests, but an accurate estimation of their biomass is still a challenge and often remains biased. Allometric equations including tree diameter and height as predictors are currently used in tropical forests, but they are often not calibrated for such large and irregular trees where measuring the diameter is quite difficult. Against this background, Manuscript II shows the result of the 3D-analysis of 12 buttressed trees. This study was conducted in the Botanical Garden of Bogor, Indonesia, using a state-of-the-art terrestrial laser scanner. The findings allow for new insights into the irregular geometry of buttressed trees and the methodological approach employed in this paper will help to improve volume and biomass models for this kind of tree. The results suggest a strong relationship (R² = 0.87) between cross-sectional areas at diameter above buttress (DAB) height and the actual tree basal area measured at 1.3 m height. The accuracy of field biomass estimates is crucial if the data are used to calibrate models to predict the forest biomass on landscape level using remote sensing imagery. The linkage between technology and methodology in the context of forest monitoring remote sensing enhance our knowledge in extracting more reliable information on tree cover estimation. The pre-processing of satellite images plays a crucial role in the processing workflow and particularly the illumination correction has a direct effect on the estimated tree cover. Manuscript IV evaluates four DEMs (Pleiades DSM, SRTM30, SRTM V4.1 and SRTM-X) that are available for the area of Shitai County (Anhui Province, Southeast China) for the purpose of an optimized illumination correction and tree cover estimation from optical RapidEye satellite images. The findings presented in this study suggest that the change in tree cover is contingent on the respective digital elevation models used for pre-processing the data. Imagery corrected with the freely available SRTM30 DEM with 30 m resolution leads to a higher accuracy in the estimation of tree cover based on the high-resolution and cost intensive Pleaides DEM. These manuscripts eventually seek to resolve some of the issues and provide answers to some of the detailed questions that still persist at different steps of the forest monitoring process. In future, these new and innovate methods and technologies will maybe integrate into forest monitoring programs

Analysis of Land Use/Land Cover Change Impacts Upon Ecosystem Services in Montane Tropical Forest of Rwanda: Forest Carbon Assessment and REDD+ Preparedness

Changes in forest cover especially changes within tropical forests, affect global climate change, together with ecosystems and forest carbon. Forests play a key role in both carbon emission and carbon sequestration. Efforts to reduce emissions through reduced deforestation and degradation of forests have become a common discussion among scientists and politicians under the auspices of the United Nations Programme on Reducing Emissions from Deforestation and Forest Degradation (UN-REDD Programme). This dissertation research assessed the impacts of land use land cover change upon ecosystem services from a protected area focusing on forest carbon distribution and vegetation mapping using remote sensing and geographical information systems (GIS). I also assessed Rwanda’s preparedness in the United Nations global program, Reducing Emissions from Deforestation and forest Degradation, Measuring, Monitoring, Reporting, and Verifying (REDD+MMRV). I carried out research in Nyungwe National Park (NNP), one of four National Parks of Rwanda. NNP is a montane tropical forest located in the Albertine Rift, one of the most biodiverse places in central and east Africa. I used remote sensing and field data collection from December 2011 and July 2012 in the western part of the Park to assess distribution and quantities of aboveground (ABG) forest carbon using generalized allometric functions. Using Landsat data together with 2009 high resolution color orthophotos and groundtruthing, I analyzed land cover changes between 1986 and 2011 for NNP. The land-use land cover change analysis showed that between 1986 and 1995 there was a minor increase in forest cover from 53% to 58% while from 1995-2003 a substantial decrease in forest cover occurred. Between 2003 and 2011 was a period of recovery with forest cover increasing by 59%. Vegetation analysis based on a 2009 Park biodiversity survey yielded 13 vegetation communities based on dominant and co-dominant species. Macaranga kilimandscharica was found to be dominant in three communities, representing 42% of the Park, and co-dominant in one community, representing 7% of the Park. While ~50% of the Park is secondary forest, the change in protection status has had a positive impact upon forest cover change within the Park. . Assessment of REDD+-MMRV readiness revealed that Rwanda has higher capacity and readiness in remote sensing and GIS than in forest inventory and carbon pools inventory. Lack of data to support development of emission models is a major problem at the national level which needs to be addressed