Applied regional monitoring of the vernal advancement and retrogradation (Green wave effect) of natural vegetation in the Great Plains corridor

The author has identified the following significant results. LANDSAT 2 has shown that digital data products can be effectively employed on a regional basis to monitor changes in vegetation conditions. The TV16 was successfully applied to an extended test site and the Great Plains Corridor in tests of the ability to assess green forage biomass on rangelands as an index to vegetation condition. A strategy for using TV16 on a regional basis was developed and tested. These studies have shown that: (1) for rangelands with good vegetative cover, such as most of the Great Plains, and which are not heavily infested with brush or undesirable weed species, the LANDSAT digital data can provide a good estimate (within 250 kg/ha) of the quantity of green forage biomass, and (2) at least five levels of pasture and range feed conditions can be adequately mapped for extended regions

Analysis of surface variables and parameterization of surface processes in HIRLAM. Part I: Approach and verification by parallel runs

The analysis of surface variables and parameterization of surface processes of the reference HIRLAM system is described. Special emphasis has been put on the treatment of surface heterogeneity making that surface uxes of heat and momentum inherit such high spacial variability. The so called “tiling" approach has been adopted to prevent the problems associated with the use of efective parameters in case of strongly changing surface conditions. The tiles are defined by coupling independently each homogeneous patch or “tile" of a grid square to the lowest level of the model. Tiles interact each other only through the atmosphere. Average surface uxes are then computed by averaging surface uxes over each land-use tile weighted by their fractional area. The model allows up to five diferent tiles (water, sea ice, bare ground, low vegetation, forest) within each grid square. Fractional snow cover is also allowed within each tile. The ISBA scheme has been selected to model land surface processes. The surface analysis initializes the following surface variables: sea surface temperature (SST), fraction of water and ice, snow depth, 2-metre temperature, 2-metre relative humidity, surface soil temperature, mean soil temperature, surface soil water content and total soil water content. The algorithm is able to cope with the tiled structure by averaging some variables only over land tiles. SST and snow depth analyses are based on the successive correction method. 2-metre temperature and relative humidity analyses are based on the optimal interpolation method. Finally, soil water content analysis is based on the sequential method, which corrects water content depending on 2-metre temperature and relative humidity forecast errors, only in those synoptic cases where screen variables are strongly inuenced by the surface beneath. A comprehensive list of parallel runs covering all seasons of the year have been conducted to demonstrate the superiority of the new package against the previous surface treatment. Special emphasis has been put on summer time and midlatitude regions were the inuence of soil wáter content on screen temperature and humidity is extremely high

衛星コンステレーション実現のためのソイルアイソラインに基づく相互校正手法に関する研究

2014年度修士論文要旨, 情報科学研究科システム科学専

Mapping soil erosion risk and safety factors of the Massanutten Trail system

Public mountain biking and hiking trails can pose challenges to trail-user safety. The purpose of this project is to improve the overall safety factors on the Massanutten Western Slope, in eastern Rockingham County, Virginia, where a 15-plus mile trail system has been made available to a broad range of users. Owned by Massanutten Resort, the trail system is in a remote, forested area frequented by local off-road cyclists, runners, hikers, as well as seasonal tourists and is maintained by the Shenandoah Valley Bicycle Coalition (SVBC). This multifaceted project, which integrates ESRI ArcGIS, Trimble Pathfinder, USDA Soil Survey Geographic (SSURGO) data, and the National Land Cover Database (NLCD), has the common goal of increasing the overall safety of the trail system through assessing both environmental impact in trail construction and use, as well as accessibility for first responders. Trail erosion risk was modeled in ArcGIS based on the variables outlined in the Revised Universal Soil Loss Equation (RUSLE). The factors of soil erodibility, slope, and vegetation cover type were used to assess erosion risk and identify areas where current trails are likely to erode and where future construction should be avoided by SVBC. Field collection of GPS locational data using a survey-grade field rover was undertaken to update trail marker signage, provide accurate locational maps for rescue efforts, and test the validity of the erosion model through ground-truthing. Cellular strength data was collected to identify areas along the trails where cellular coverage may be weak. Ultimately, first responders will be provided with maps of the trail system labeled with geographic coordinates and that identify access points

Generating Global Leaf Area Index from Landsat: Algorithm Formulation and Demonstration

This paper summarizes the implementation of a physically based algorithm for the retrieval of vegetation green Leaf Area Index (LAI) from Landsat surface reflectance data. The algorithm is based on the canopy spectral invariants theory and provides a computationally efficient way of parameterizing the Bidirectional Reflectance Factor (BRF) as a function of spatial resolution and wavelength. LAI retrievals from the application of this algorithm to aggregated Landsat surface reflectances are consistent with those of MODIS for homogeneous sites represented by different herbaceous and forest cover types. Example results illustrating the physics and performance of the algorithm suggest three key factors that influence the LAI retrieval process: 1) the atmospheric correction procedures to estimate surface reflectances; 2) the proximity of Landsatobserved surface reflectance and corresponding reflectances as characterized by the model simulation; and 3) the quality of the input land cover type in accurately delineating pure vegetated components as opposed to mixed pixels. Accounting for these factors, a pilot implementation of the LAI retrieval algorithm was demonstrated for the state of California utilizing the Global Land Survey (GLS) 2005 Landsat data archive. In a separate exercise, the performance of the LAI algorithm over California was evaluated by using the short-wave infrared band in addition to the red and near-infrared bands. Results show that the algorithm, while ingesting the short-wave infrared band, has the ability to delineate open canopies with understory effects and may provide useful information compared to a more traditional two-band retrieval. Future research will involve implementation of this algorithm at continental scales and a validation exercise will be performed in evaluating the accuracy of the 30-m LAI products at several field sites

An integrated study of earth resources in the state of California using remote sensing techniques

There are no author-identified significant results in this report

Intercomparison of Flow and Transport Models Applied to Vertical Drainage in Cropped Lysimeters

International audienceThe vertical water flow, heat flow and transport of the herbicide methabenzthiazuron were monitored for 627 days in lysimeters sampled at a field site close to the research centre Jülich, Germany. During this period the lysimeters were cropped with winter wheat, winter barley and oat. The models TRACE, MARTHE, ANSWERS and MACRO were applied to the lysimeter data with the scope of upscaling local scale process understanding for regional scale. MARTHE and TRACE solve the 3-d Richards' equation for variably saturated water flow. MACRO is a 1-d model based on the Richards' Equation and accounting for preferential flow in the unsaturated zone, while ANSWERS is a regional scale capacity based watershed model. Measurements of soil moisture, evapotranspiration, drainage, soil temperature, pesticide residues and leaching are used for comparison with model results. Although the adopted models differ in terms of model concepts, the use of model performance indices proved a proper simulation of water flow for all models. The heat flow is also well described with ANSWERS, MARTHE and MACRO. Larger deviations were found between model results and measured pesticide transport. An inadequate reproduction of the measured MBT degradation was found for the available model input parameters. A very small amount of MBT leaching, observed in the measurements, was only reproduced with MACRO after strong calibration. In other respects only plant parameters were calibrated. Calibration of the crop conversion factor used for scaling of the potential evapotranspiration was found to be a crucial parameter for the adequate description of the water balance by the models

Effect of Phytophthora cinnamomi on the habitat utilization of Antechinus stuartii in a Victorian forest

Phytophthora cinnamomi (Cinnamon fungus) is a pathogenic soil fungus which infects plant communities along the south-eastern coast of Australia, and the south-western corner of Western Australia. The symptoms of this disease include chlorosis, death of branches (ie. ‘dieback’), retarded growth and the eventual death of infected plants. This leads to devastating effects upon plant communities by altering both the structural and floristic characteristics of these communities. Small mammal species are dependent on specific features of their habitat such as vegetation structure and floristics. This thesis investigated alterations to the habitat of the insectivorous marsupial mouse, Antechinus stuartii, due to the presence of P. cinnamomi. The study was undertaken in an area of an open forest in the Brisbane Ranges, Victoria. Significant changes were found in both the floristic composition and structure of the vegetation at study sites infected with P, cinnamomi, compared to uninfected sites. The habitat utilization by A. stuartii of uninfected and infected vegetation was investigated using live trapping and radio-telemetric techniques. Capture rates were higher at sites uninfected by P. cinnamomi, and both male and females selected areas free from infection. Home range areas of males were significantly larger than those of females as assessed by telemetry. Both sexes spent a high proportion of time in areas dominated by Xanthorrhoea australis (Austral grass tree). There were significant relationships between the abundance of A. stuartii and the denseness of vegetation above 1 metre in height, and in particular, the proportion of cover afforded by X. australis. There were no significant differences in the cover of Eucalyptus spp. between uninfected and infected sites, but there were significantly more nest hollows in infected areas. The abundance of invertebrates was examined using pitfall traps. There were no significant differences in the abundance of the larger invertebrate taxa at infected and uninfected sites, but higher abundances of some micro-invertebrate groups in infected areas were recorded. The most likely factors considered to be influential in the habitat selection of A. stuartii were vegetation structure, and the presence of X. australis. To assess whether these factors were important the leaves of X. australis were removed with a brushcutter, to mimic the early effects of infection with P. cinnamomi. Animals did not respond to the alteration of vegetation structure in the short term (3-4 days). Longer-term experiments are required to assess the habitat utilization of A. stuartii at different periods following habitat manipulation. The implications of the presence of P. cinnamomi on the conservation of fauna are discussed. The destructive nature of the pathogen, and the slow rate of recovery from the disease, means that P. cinnamomi can be considered a threatening process to plant communities and the fauna that reside within that habitat. Future management of this disease within natural areas must therefore be cognisant of the potential of P. cinnamomi to significantly affect faunal as well as vegetative communities

Partitioning of carbon dioxide exchange in rapidly and slowly changing ecosystems

Im Hinblick auf den aktuellen Klimawandel besteht die Frage, wie die Biosphäre auf den Globalen Wandel und die daraus hervorgehende lokale Landnutzungsänderung bezüglich ihres Kohlenstoffkreislaufes reagiert. Die Landoberfläche ist zum gegenwärtigen Zeitpunkt eine Senke für anthropogene Emissionen von Kohlenstoffdioxid (CO2), jedoch wird gleich-zeitig durch Landnutzungsänderungen zusätzliches CO2 freigesetzt. Nach wie vor ist nicht eindeutig geklärt, wie sensitiv die photosynthetische CO2-Aufnahme und die atmungsbedingte CO2-Freisetzung eines Ökosystems gegenüber Umweltparametern reagieren. Eine Möglichkeit, den vertikalen Fluss der Treibhausgase in ihre Quellen und Senken aufzuspalten, bietet das sogenannte Source-Partitioning. Hierbei werden z. B. vertikale CO2-Flüsse in Photosynthese und Respiration oder im Fall von Wasserdampfflüssen (H2O) in Evaporation und Transpiration aufgetrennt. Derzeitig existieren mehrere Ansätze und Verfahren für das Source-Partitioning, jedoch besitzt jede Methode auch gewisse Nachteile und läßt Raum für Erweiterungen und Verbesserungen. In dieser Arbeit wird zum einen ein Ansatz getestet, der sogenannte Zusatzmessungen benötigt und zum anderen eine analytische Partitionierungsmethode aufgegriffen. Beide Ansätze werden anhand von Fallbeispielen in Agrar- und Waldökosystemen demonstriert und untersucht. Zuerst wird der Prototyp einer mobilen Liftanlage präsentiert, mit der zeitlich sowie räumlich hochaufgelöste Messung von CO2-, H2O-, Temperatur- und Windgeschwindigkeitsprofilen zwischen der Bodenoberfläche und der erdnahen atmosphärischen Grenzschicht über der Pflanzenoberfläche eines Ackers durchgeführt wurden. Die vertikale Verteilung der Konzentrationen von CO2 und H2O kann somit qualitativ für einen dichten Pflanzenbestand bestimmt werden. Dafür wurden zwischen Frühjahr 2015 und Herbst 2016 Kampagnenmessungen in Winterweizen, Wintergerste und einer Zwischenfruchtmischung während verschiedenen Stadien der Pflanzenentwicklung und zu unterschiedlichen Tageszeiten durchgeführt. Mit Hilfe eines Gasanalysators wurden kontinuierlich über eine Profilhöhe von 2 m die Konzentrationen mit einer Frequenz von 20 s-1 aufgezeichnet. Wir demonstrieren die Nachbearbeitung der Messungen (z. B. die Korrektur von Zeitverzögerungen) und zeigen die resultierenden vertikalen Profile als 30-minütige Mittel mit einer Auflösung von 0.025 m. Die Profile zeigen innerhalb des Planzenbestandes deutlich die Effekte der Bodenatmung und der photosynthetischen Kohlenstoffaufnahme, die sowohl innerhalb der Tageszeiten als auch während der Vegetationsperiode variieren. Mit Hilfe der Monin-Obukhov'schen Ähnlichkeitstheorie wurden Messungen über unbewachsenem Boden und einer niedrigen Pflanzendecke analysiert, um die Validität der Profilmessungen und der Rohdatenverarbeitung zu überprüfen. Die abgeleiteten Flüsse von CO2, latente und sensible Wärme und Impuls zeigen eine gute Übereinstimmung zu den parallel durchgeführten Eddy-Kovarianz-Messungen. Während die Kohlenstoffbilanz einer Ackerfläche im Laufe einer Vegetationsperiode zwischen Quelle und Senke wechselt, dauert dieser Prozess in bewirtschafteten Waldökosystemen meist Jahrzehnte. Im Allgemeinen nehmen Wälder in Mitteleuropa im Jahresmittel mehr CO2 auf, als sie abgeben und stellen somit eine Senke für atmosphärisches CO2 dar. Diese Situation kann sich ändern, sobald ein Eingriff in das Waldökosystem stattfindet. Ein Extrembeispiel eines solchen Eingriffs sind flächenhafte Kahlschläge, die den Wald nach der Abholzung von einer ehemaligen Senke zu einer Quelle für CO2 umwandeln. In dieser Arbeit präsentiert werden sieben Jahre CO2-Flussmessungen über einer rund 70 Jahre alten Fichten-Monokulturfläche im Nationalpark Eifel, von der rund 20% drei Jahre nach Beginn der Messung abgeholzt wurden. Ein Eddy-Kovarianz-System, das auf einem 37.8 m hohen Turm innerhalb des Waldes montiert wurde, erfasste kontinuierlich Flüsse sensibler und latenter Wärme, CO2 und Impuls. Nach der teilweisen Entfichtung wurde eine zweite EC-Station innerhalb der Entfichtungsfläche installiert und parallel zur Waldstation betrieben. Komplette Zeitreihen und jährliche Kohlenstoffbilanzen des Netto-Ökosystemaustauschs von CO2 (NEE) und seiner Komponenten Brutto-Primärproduktion (GPP) und Ökosystematmung (Reco) wurden mit Hilfe von Gapfilling- und Source-Partition-ing Methoden berechnet. Daneben wird die gemessene Bodenatmung berücksichtigt und dich sich gegenüberstehenden Klimaeffekte der durch die Entfichtung veränderten CO2-Sequestrierung und dem biophysikalischen Effekt der geänderten Albedo betrachtet. Im Gegensatz zur abgeholzten Fläche zeigten die über dem Wald gemessenen jährlichen NEE-Summen eine starke Kohlenstoffsenke mit geringer zwischenjährlicher Variabilität. Ein Jahr nach der Entfichtung bestand die Vegetation auf der abgeholzten Fläche hauptsächlich aus Gräsern und Sträuchern; ab dem zweiten Jahr konnte ein vermehrter Zuwachs neuer Bäume (vorwiegend Eberesche) beobachtet werden. Die wiederaufkommende Vegetation spiegelte sich in den jährlichen Summen des NEE wieder, so entwickelte sich die Entfichtungsfläche von einer Kohlenstoffquelle (ca. 500 g C m-2 y-1) innerhalb der betrachteten vier Jahre aufgrund der Zunahme photosynthetischer Aktivitäten zunehmend zu einem CO2 neutralen Zustand. Im anschließenden Kapitel wird die Kohlenstoffbilanz eines Ackers über eine drei Jahre andauernde Fruchtwechselfolge untersucht. Der Versuchsstandort Selhausen befindet sich in einer landwirtschaftlich intensiv genutzen Region innerhalb der Niederrheinischen Bucht. Rund 34% der Fläche Deutschlands war im Jahr 2015 durch Landwirtschaft genutzt (FAO, 2015). Die Fähigkeit von landwirtschaftlichen Flächen Kohlenstoff zu binden, aber auch zu emittieren, ist von großer Bedeutung für den lokalen und globalen Kohlenstoffkreislauf. Um eine lokale Kohlenstoffbilanz für ein Agrarökosystem aufstellen und modellieren zu können, benötigt man neben dem gemessenen vertikalen Netto-Ökosystemaustausch zusätzliche Informationen bezüglich seiner Zusammensetzung aus Brutto-Primärproduktion und Ökosystematmung. Die in Ökosystemstudien am häufigsten genutzten Partitionierung-Methoden sind die sogenannten datenbasierenden nichtlinearen Funktionen (NLR). Sie beschreiben den nichtlinearen Zusammenhang zwischen dem gemessenen NEE und Umgebungsvariablen wie Lufttemperatur oder solare Strahlung, die maßgeblich Atmungs- und Photosyntheseprozesse steuern. In der hier vorgestellten Studie wird für die Aufteilung der gemessenen NEE über einer 3-jährigen Fruchtwechselfolge, bestehend aus Winterweizen / Wintergerste / Zwischenfrucht und Zuckerrübe, der Ansatz einer reinen Nacht- (NT) und einer größtenteils Tagdaten (DT) basierenden NLR benutzt. Zusätzlich wurde ein eigener Algorithmus entwickelt und implementiert, der NLR ohne eine vorangehende Aufteilung in Tag- und Nachtdaten berechnet. Der Verlauf der saisonalen und zwischenjährlichen Flüsse von NEE, GPP und Reco zeigten typische Muster und Größenordnungen einer landwirtschaftlich genutzen Fläche innerhalb Mitteleuropas. Die kumulierten Tagessummen der NEE variierten je nach angebauter Frucht und Jahreszeit zwischen +10 und -14 g C m-2 d-1. Die höchste CO2-Aufnahme fand zwischen Mai und Juni im Winterweizen statt. Die höchsten Emissionen wurden nach der Ernte von Wintergerste beobachtet, wobei vermutlich untergepflügte Erntereste im Boden einen Anstieg der Bodenatmung durch Dekompositionsvorgänge begünstigt haben. Über die komplette Fruchtwechselfolge und bei reiner Betrachtung des vertikalen CO2-Flusses zeigte das Ökosystem, je nach verwendetem Partitionierungsmodell, eine Netto-CO2-Aufnahme von -1.3 bis -1,6 kg C m-2 und stellte somit eine Senke für Kohlenstoff dar. Werden zusätzlich zum NEE der Kohlenstoffeintrag und -austrag durch Sähen und Ernte, sowie die Emissionen aus Feldbewirtschaftungsmaßnahmen in der Kohlenstoffbilanzierung berücksichtigt, wird der Acker eine Kohlenstoffquelle (0.7 bis 1.0 kg C m-2). Beim Vergleich der unterschiedlichen NLR fiel auf, dass die Anwendung, die ausschließlich auf Nachtdaten basiert, grundsätzlich höhere Werte der Ökosystematmung ermittelt, als die anderen verwendeten Methoden. So kam es in den kummulierten Flüssen zu Abweichungen von 16%, 6% und 15% zwischen NEE, GPP und Reco im Vergleich zwischen NT und DT. Geringer fielen die Unterschiede zwischen NT und der eigenen Methode aus. Auch andere Studien berichten von Diskrepanzen in der Partitionierung von NEE bei der Verwendung der oben beschriebenen Methoden. Diese und auch unsere Arbeit zeigen, dass weiterhin Forschungsbedarf hinsichtlich der Anwendung von Source-Partitioning besteht.A key question in times of climate change is, how the biosphere responds to global change and the local land use management in regard to its carbon cycle. At the present time, the land surface acts as a sink for anthropogenic carbon dioxide (CO2) emissions. However, additional CO2 is released simultaneously by land use change. There is still no clear understanding of the sensitivity of photosynthetic CO2 uptake and respiratory CO2 release to environmental parameters. One possible way to disentangle the flux of greenhouse gases is source-partitioning, e.g. into photosynthesis and respiration (CO2) or into evaporation and transpiration (H2O). Currently, there are a number of procedures for source-partitioning, however, each method has its disadvantages and allows for extensions and improvements. In this thesis, one instrumental and a data-driven partitioning approaches are taken up and demonstrated by examples of an agro- and forest ecosystem. First, we present the prototype of a portable elevator based device for measuring temporal and spatial high-resolution profiles of CO2, H2O, temperature and wind velocity between the soil surface and the atmospheric surface layer above crop canopies. The vertical distribution of CO2 and H2O concentrations can thus be determined qualitatively for dense crop stands. Between spring 2015 and autumn 2016, campaign measurements were carried out in winter wheat, winter barley, and in an intercrop mixture during different plant development stage and at different times of day. A gas analyzer continuously records the concentrations at a frequency of 20 s-1 over a 2 m profile height. We present a post-processing technique of the measurements (e.g. the correction of time lags) and show the resulting vertical profiles as 30-minute averages over height steps of 0.025 m. The profiles clearly show the effects of soil respiration and photosynthetic carbon uptake within the plant stand, which vary both during the time of day and during the vegetation period. Using the Monin-Obukhov similarity theory, measurements over bare soil and a short plant canopy were analyzed to check the validity of the elevator measurements and the raw data processing. It was found that the derived fluxes of CO2, latent and sensible heat, and momentum correlated well with eddy-covariance (EC) measurements. While the carbon balance of an agricultural area alternates between source and sink during a vegetation period, this process usually requires decades for the management of forest ecosystems. In general, forests in Central Europe assimilate more CO2 on an annual average than they emit and thus are a sink for atmospheric CO2. This may change as soon as the forest ecosystem is intervened. An extreme example of such an intervention is clear cutting. After deforestation, the forest changes from a former sink to a source of CO2. We present seven years of CO2 flux measurements over a 70 year old spruce monoculture in the Eifel National Park, from which about 20% were deforested three-years after beginning of the observation period. An EC system mounted on top of a 37.8 m high tower within the forest, continuously collects fluxes of sensible and latent heat, CO2 and momentum. After partial deforestation, a second EC station was installed within the deforested area and was running parallel to the forest station. Complete time series and annual carbon budgets of the net ecosystem exchange (NEE) of CO2 and its components, gross primary production (GPP) and ecosystem respiration (Reco), were calculated using gap-filling and source-partitioning methods. In addition, local chamber measurements of soil respiration are taken into account and the climatic effects of the changed CO2 sequestration and the biophysical effect of changed albedo are compared. In contrast to the deforested area, the annual sums of NEE measured above the forest show a strong carbon sink with low inter-annual variability. One year after deforestation, the vegetation on the deforested area consisted mainly of grasses and shrubs; from the second year onwards, an increased growth of new trees (mainly mountain ash) could be observed. The recovering vegetation is reflected in the annual sums of NEE, which decreased from a carbon source (500 g C m-2 y-1) towards neutral over the past four years, due to an increase in the photosynthetic activities. In the last chapter, the carbon balance of a three-year crop rotation cycle was examined. The study site Selhausen is located in an intensively managed agricultural region within the Lower Rhine Embayment. About 34% of the area of Germany was covered by agriculture in 2015 (FAO, 2015). The ability of agricultural areas to sequester or also to emit carbon gives them an important role in the local and global carbon cycle. In order to calculate or to model the local carbon balance for an agroecosystem, information about the measured NEE and its components GPP and Reco are needed. The most frequently used partitioning methods in ecosystem studies are the so-called data-based nonlinear regression functions (NLR). NLR describes the nonlinear relationship between the measured NEE and environmental variables, such as air temperature or solar radiation, which are the main drivers of respiration and photosynthetic processes. The study presented here uses a nighttime (NT) and daytime data based (DT) NLR approach for the partitioning of measured NEE in a 3-year crop rotation cycle, consisting of winter wheat / winter barley / catch-crop and sugar beet. In addition, an own algorithm was developed and implemented that calculates NLR without a previous separation of the dataset into day- and nighttime data. The seasonal and inter-annual fluxes of NEE, GPP and Reco showed typical patterns and orders of magnitude of an agroecosystem within Central Europe. The cumulated daily sums of the NEE varied between +10 and -14 g C m-2 d-1 depending on the cultivated crop and season. The highest CO2 uptake took place between May and June in winter wheat. The highest emissions were observed after harvest of winter barley, when crop residues in the soil favoring an increase in soil respiration due to decomposition processes. Over the 3-year crop rotation, the ecosystem acted as a carbon source with a release of 0.7 to 1.0 kg C m-2, depending on the used source-partitioning model. Comparing the different NLR methods, it became apparent that the NT based application overestimated Reco compared to the other methods, resulting in deviations in NT vs. DT of 16%, 6% and 15% between the cumulated fluxes of NEE, GPP and Reco. The differences between NT and the own method were in general smaller. Other studies also reported discrepancies in the partitioning of NEE using the methods described above. Their and our work shows that there is still a need for further investigation regarding source-partitioning strategies