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Article: Heterotrophic and rhizospheric respiration in coniferous forest soils along a latitudinal gradient

Mäki, Mari / Ryhti, Kira / Fer, Istem / Ťupek, Boris / Vestin, Patrik / Roland, Marilyn / Lehner, Irene / Köster, Egle / Lehtonen, Aleksi / Bäck, Jaana / Heinonsalo, Jussi / Pumpanen, Jukka / Kulmala, Liisa

Agricultural and forest meteorology. 2022 Apr. 15, v. 317

2022

Abstract: Northern forest soils are a major carbon (C) reservoir of global importance. To estimate how the C balance in these soils will change, the roles of tree roots and soil microbes in C balance should first be decoupled. This study determined how the ... ...

Abstract	Northern forest soils are a major carbon (C) reservoir of global importance. To estimate how the C balance in these soils will change, the roles of tree roots and soil microbes in C balance should first be decoupled. This study determined how the activity of heterotrophs and tree roots together with root-associated microbes in the rhizosphere varies in coniferous forest soils in boreal, hemiboreal, and temperate climates along a latitudinal gradient using a trenching approach. We created experimental plots without living tree roots, measured soil respiration (CO₂ efflux) from these and from unmanipulated plots using the chamber technique, and partitioned the efflux into root-rhizosphere (RR) and heterotrophic (RH) respiration. The share of RR in ecosystem gross primary production (GPP) decreased from north to south in the Scots pine (Pinus sylvestris L.) and the Norway spruce (Picea abies (L.) Karst.) forests, with the exception of a mixed site, where the share of RR in GPP varied strongly between the years. RR per ground area and per root biomass were mainly independent of climate within the gradient. RH per ground area increased from north to south with temperature, while RH per soil C did not change with temperature. Soil moisture did not significantly affect the respiration components in the northernmost site, whereas soil moisture was positively connected with RH and negatively with RR in other Scots pine sites and positively connected with RR in pure Norway spruce stands. The dynamic ecosystem model LPJ-GUESS was able to capture the seasonal dynamics of RH and RR at the sites, but overall accuracy varied markedly between the sites, as the model underestimated RH in the southern site and RR elsewhere. Our study provides knowledge about the nature of soil respiration components. The valuable insights can be used in more accurate land-ecosystem modelling of forest ecosystems.
Keywords	Picea abies ; Pinus sylvestris ; biomass ; carbon ; carbon dioxide ; coniferous forests ; ecological models ; gross primary productivity ; heterotrophs ; meteorology ; rhizosphere ; soil respiration ; soil water ; temperature
Language	English
Dates of publication	2022-0415
Publishing place	Elsevier B.V.
Document type	Article
ZDB-ID	409905-9
ISSN	0168-1923
ISSN	0168-1923
DOI	10.1016/j.agrformet.2022.108876
Database	NAL-Catalogue (AGRICOLA)

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Article: High-resolution modelling closes the gap between data and model simulations for Mid-Holocene and present-day biomes of East Africa

Fer, Istem / Britta Tietjen / Florian Jeltsch

Palaeogeography, palaeoclimatology, palaeoecology. 2016 Feb. 15, v. 444

2016

Abstract: East Africa hosts a striking diversity of terrestrial ecosystems, which vary both in space and time due to complex regional topography and a dynamic climate. The structure and functioning of these ecosystems under this environmental setting can be ... ...

Abstract	East Africa hosts a striking diversity of terrestrial ecosystems, which vary both in space and time due to complex regional topography and a dynamic climate. The structure and functioning of these ecosystems under this environmental setting can be studied with dynamic vegetation models (DVMs) in a spatially explicit way. Yet, regional applications of DVMs to East Africa are rare and a comprehensive validation of such applications is missing. Here, we simulated the present-day and mid-Holocene vegetation of East Africa with the DVM, LPJ-GUESS and we conducted an exhaustive comparison of model outputs with maps of potential modern vegetation distribution, and with pollen records of local change through time. Overall, the model was able to reproduce the observed spatial patterns of East African vegetation. To see whether running the model at higher spatial resolutions (10′×10′) contribute to resolve the vegetation distribution better and have a better comparison scale with the observational data (i.e. pollen data), we run the model with coarser spatial resolution (0.5°×0.5°) for the present-day as well. Both the area- and point-wise comparison showed that a higher spatial resolution allows to better describe spatial vegetation changes induced by the complex topography of East Africa. Our analysis of the difference between modelled mid-Holocene and modern-day vegetation showed that whether a biome shifts to another is best explained by both the amount of change in precipitation it experiences and the amount of precipitation it received originally. We also confirmed that tropical forest biomes were more sensitive to a decrease in precipitation compared to woodland and savanna biomes and that Holocene vegetation changes in East Africa were driven not only by changes in annual precipitation but also by changes in its seasonality.
Keywords	atmospheric precipitation ; climate ; hosts ; observational studies ; pollen ; population distribution ; savannas ; simulation models ; space and time ; terrestrial ecosystems ; topography ; tropical forests ; woodlands ; Eastern Africa
Language	English
Dates of publication	2016-0215
Size	p. 144-151.
Publishing place	Elsevier B.V.
Document type	Article
ZDB-ID	417718-6
ISSN	0031-0182
ISSN	0031-0182
DOI	10.1016/j.palaeo.2015.12.001
Database	NAL-Catalogue (AGRICOLA)

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Book ; Online ; Thesis: Modeling past, present and future climate induced vegetation changes in East Africa

Fer, Istem [Verfasser] / Jeltsch, Florian [Akademischer Betreuer]

2018

Author's details	Istem Fer ; Betreuer: Florian Jeltsch
Keywords	Pflanzen (Botanik) ; Plants (Botany)
Subject code	sg580
Language	English
Publisher	Universität Potsdam
Publishing place	Potsdam
Document type	Book ; Online ; Thesis
Database	Digital theses on the web

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Book ; Online: Cutting out the middleman

Shiklomanov, Alexey N. / Dietze, Michael C. / Fer, Istem / Viskari, Toni / Serbin, Shawn P.

eISSN: 1991-9603

Calibrating and validating a dynamic vegetation model (ED2-PROSPECT5) using remotely sensed surface reflectance

2020

Abstract: Ecosystem models are often calibrated and/or validated against derived remote sensing data products, such as MODIS leaf area index. However, these data products are generally based on their own models, whose assumptions may not be compatible with those ... ...

Abstract	Ecosystem models are often calibrated and/or validated against derived remote sensing data products, such as MODIS leaf area index. However, these data products are generally based on their own models, whose assumptions may not be compatible with those of the ecosystem model in question, and whose uncertainties are usually not well quantified. Here, we develop an alternative approach whereby we modify an ecosystem model to predict full-range, high spectral resolution surface reflectance, which can then be compared directly against airborne and satellite data. Specifically, we coupled the two-stream representation of canopy radiative transfer in the Ecosystem Demography model (ED2) with a leaf radiative transfer model (PROSPECT 5) and a simple soil reflectance model. We then calibrated this model against reflectance observations from the NASA Airborne VIsible/InfraRed Imaging Spectrometer (AVIRIS) and survey data from 54 temperate forest plots in the northeastern United States. The calibration successfully constrained the posterior distributions of model parameters related to leaf biochemistry and morphology and canopy structure for five plant functional types. The calibrated model was able to accurately reproduce surface reflectance and leaf area index for sites with highly varied forest composition and structure, using a single common set of parameters across all sites. We conclude that having dynamic vegetation models directly predict surface reflectance is a promising avenue for model calibration and validation using remote sensing data.
Subject code	551
Language	English
Publishing date	2020-10-12
Publishing country	de
Document type	Book ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Book ; Online: Soil carbon estimates by Yasso15 model improved with state data assimilation

Viskari, Toni / Laine, Maisa / Kulmala, Liisa / Mäkela, Jarmo / Fer, Istem / Liski, Jari

eISSN: 1991-9603

2020

Abstract: Model-calculated forecasts of soil organic carbon (SOC) are important for approximating global terrestrial carbon pools and assessing their change. However, the lack of detailed observations limits the reliability and applicability of these SOC ... ...

Abstract	Model-calculated forecasts of soil organic carbon (SOC) are important for approximating global terrestrial carbon pools and assessing their change. However, the lack of detailed observations limits the reliability and applicability of these SOC projections. Here, we studied if state data assimilation (SDA) can be used to continuously update the modeled state with available total carbon measurements in order to improve future SOC estimations. We chose six fallow test sites with measurements time series spanning 30 to 80 years for this initial test. In all cases, SDA improved future projections but to varying degrees. Furthermore, already including the first few measurements impacted the state enough to reduce the error in decades long projections in by at least 1 t C ha −1 . Our results show the benefits of implementing SDA methods for forecasting SOC, but also highlight implementation aspects that need consideration and further research.
Subject code	333
Language	English
Publishing date	2020-07-02
Publishing country	de
Document type	Book ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Book ; Online: Improving Yasso15 soil carbon model estimates with ensemble adjustment Kalman filter state data assimilation

Viskari, Toni / Laine, Maisa / Kulmala, Liisa / Mäkelä, Jarmo / Fer, Istem / Liski, Jari

eISSN: 1991-9603

2020

Abstract	Model-calculated forecasts of soil organic carbon (SOC) are important for approximating global terrestrial carbon pools and assessing their change. However, the lack of detailed observations limits the reliability and applicability of these SOC projections. Here, we studied whether state data assimilation (SDA) can be used to continuously update the modeled state with available total carbon measurements in order to improve future SOC estimations. We chose six fallow test sites with measurement time series spanning 30 to 80 years for this initial test. In all cases, SDA improved future projections but to varying degrees. Furthermore, already including the first few measurements impacted the state enough to reduce the error in decades-long projections by at least 1 t C ha −1 . Our results show the benefits of implementing SDA methods for forecasting SOC as well as highlight implementation aspects that need consideration and further research.
Subject code	333
Language	English
Publishing date	2020-12-01
Publishing country	de
Document type	Book ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article: Modelling vegetation change during Late Cenozoic uplift of the East African plateaus

Fer, Istem / Britta Tietjen / Florian Jeltsch / Martin H. Trauth

Palaeogeography, palaeoclimatology, palaeoecology. 2017 Feb. 01, v. 467

2017

Abstract: The present-day vegetation in the tropics is mainly characterized by forests worldwide except in tropical East Africa, where forests only occur as patches at the coast and in the uplands. These forest patches result from the peculiar aridity that is ... ...

Abstract	The present-day vegetation in the tropics is mainly characterized by forests worldwide except in tropical East Africa, where forests only occur as patches at the coast and in the uplands. These forest patches result from the peculiar aridity that is linked to the uplift of the region during the Late Cenozoic. The Late Cenozoic vegetation history of East Africa is of particular interest as it has set the scene for the contemporary events in mammal and hominin evolution. In this study, we investigate the conditions under which these forest patches could have been connected, and a previous continuous forest belt could have extended and fragmented. We apply a dynamic vegetation model with a set of climatic scenarios in which we systematically alter the present-day environmental conditions such that they would be more favourable for a continuous forest belt in tropical East Africa. We consider varying environmental factors, namely temperature, precipitation and atmospheric CO2 concentrations. Our results show that all of these variables play a significant role in supporting the forest biomes and a continuous forest belt could have occurred under certain combinations of these settings. With our current knowledge of the palaeoenvironmental history of East Africa, it is likely that the region hosted these conditions during the Late Cenozoic. Recent improvements on environmental hypotheses of hominin evolution highlight the role of periods of short and extreme climate variability during the Late Cenozoic specific to East Africa in driving evolution. Our results elucidate how the forest biomes of East Africa can appear and disappear under fluctuating environmental conditions and demonstrate how this climate variability might be recognized on the biosphere level.
Keywords	biosphere ; carbon dioxide ; Cenozoic era ; coasts ; dry environmental conditions ; ecosystems ; evolution ; forests ; highlands ; mammals ; models ; paleoecology ; temperature ; tropics ; Eastern Africa
Language	English
Dates of publication	2017-0201
Size	p. 120-130.
Publishing place	Elsevier B.V.
Document type	Article
ZDB-ID	417718-6
ISSN	0031-0182
ISSN	0031-0182
DOI	10.1016/j.palaeo.2016.04.007
Database	NAL-Catalogue (AGRICOLA)

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Article: Beyond ecosystem modeling: A roadmap to community cyberinfrastructure for ecological data‐model integration

Fer, Istem / Gardella, Anthony K / Shiklomanov, Alexey N / Campbell, Eleanor E / Cowdery, Elizabeth M / De Kauwe, Martin G / Desai, Ankur / Duveneck, Matthew J / Fisher, Joshua B / Haynes, Katherine D / Hoffman, Forrest M / Johnston, Miriam R / Kooper, Rob / LeBauer, David S / Mantooth, Joshua / Parton, William J / Poulter, Benjamin / Quaife, Tristan / Raiho, Ann /

Schaefer, Kevin / Serbin, Shawn P / Simkins, James / Wilcox, Kevin R / Viskari, Toni / Dietze, Michael C

Global change biology. 2021 Jan., v. 27, no. 1

2021

Abstract: In an era of rapid global change, our ability to understand and predict Earth's natural systems is lagging behind our ability to monitor and measure changes in the biosphere. Bottlenecks to informing models with observations have reduced our capacity to ... ...

Abstract	In an era of rapid global change, our ability to understand and predict Earth's natural systems is lagging behind our ability to monitor and measure changes in the biosphere. Bottlenecks to informing models with observations have reduced our capacity to fully exploit the growing volume and variety of available data. Here, we take a critical look at the information infrastructure that connects ecosystem modeling and measurement efforts, and propose a roadmap to community cyberinfrastructure development that can reduce the divisions between empirical research and modeling and accelerate the pace of discovery. A new era of data‐model integration requires investment in accessible, scalable, and transparent tools that integrate the expertise of the whole community, including both modelers and empiricists. This roadmap focuses on five key opportunities for community tools: the underlying foundations of community cyberinfrastructure; data ingest; calibration of models to data; model‐data benchmarking; and data assimilation and ecological forecasting. This community‐driven approach is a key to meeting the pressing needs of science and society in the 21st century.
Keywords	Biological Sciences ; biosphere ; ecosystems ; empirical research ; global change ; infrastructure
Language	English
Dates of publication	2021-01
Size	p. 13-26.
Publishing place	John Wiley & Sons, Ltd
Document type	Article
Note	NAL-AP-2-clean ; JOURNAL ARTICLE
ZDB-ID	1281439-8
ISSN	1365-2486 ; 1354-1013
ISSN (online)	1365-2486
ISSN	1354-1013
DOI	10.1111/gcb.15409
Database	NAL-Catalogue (AGRICOLA)

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Book ; Online: Towards agricultural soil carbon monitoring, reporting and verification through Field Observatory Network (FiON)

Nevalainen, Olli / Niemitalo, Olli / Fer, Istem / Juntunen, Antti / Mattila, Tuomas / Koskela, Olli / Kukkamäki, Joni / Höckerstedt, Layla / Mäkelä, Laura / Jarva, Pieta / Heimsch, Laura / Vekuri, Henriikka / Kulmala, Liisa / Stam, Åsa / Kuusela, Otto / Gerin, Stephanie / Viskari, Toni / Vira, Julius / Hyväluoma, Jari /

Tuovinen, Juha-Pekka / Lohila, Annalea / Laurila, Tuomas / Heinonsalo, Jussi / Aalto, Tuula / Kunttu, Iivari / Liski, Jari

eISSN: 2193-0864

2021

Abstract: Better monitoring, reporting and verification (MRV) of the amount, additionality and persistence of the sequestered soil carbon is needed to understand the best carbon farming practices for different soils and climate conditions, as well as their actual ... ...

Abstract	Better monitoring, reporting and verification (MRV) of the amount, additionality and persistence of the sequestered soil carbon is needed to understand the best carbon farming practices for different soils and climate conditions, as well as their actual climate benefits or cost-efficiency in mitigating greenhouse gas emissions. This paper presents our Field Observatory Network (FiON) of researchers, farmers, companies and other stakeholders developing carbon farming practices. FiON has established a unified methodology towards monitoring and forecasting agricultural carbon sequestration by combining offline and near real-time field measurements, weather data, satellite imagery, modeling and computing networks. FiON’s first phase consists of two intensive research sites and 20 voluntary pilot farms testing carbon farming practices in Finland. To disseminate the data, FiON built a web-based dashboard called Field Observatory (v1.0, fieldobservatory.org ). Field Observatory is designed as an online service for near real-time model-data synthesis, forecasting and decision support for the farmers who are able to monitor the effects of carbon farming practices. The most advanced features of the Field Observatory are visible on the Qvidja site which acts as a prototype for the most recent implementations. Overall, FiON aims to create new knowledge on agricultural soil carbon sequestration and effects of carbon farming practices, and provide an MRV tool for decision-support.
Subject code	333
Language	English
Publishing date	2021-08-02
Publishing country	de
Document type	Book ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Beyond ecosystem modeling: A roadmap to community cyberinfrastructure for ecological data-model integration.

Schaefer, Kevin / Serbin, Shawn P / Simkins, James / Wilcox, Kevin R / Viskari, Toni / Dietze, Michael C

Global change biology

2020 Volume 27, Issue 1, Page(s) 13–26

Abstract	In an era of rapid global change, our ability to understand and predict Earth's natural systems is lagging behind our ability to monitor and measure changes in the biosphere. Bottlenecks to informing models with observations have reduced our capacity to fully exploit the growing volume and variety of available data. Here, we take a critical look at the information infrastructure that connects ecosystem modeling and measurement efforts, and propose a roadmap to community cyberinfrastructure development that can reduce the divisions between empirical research and modeling and accelerate the pace of discovery. A new era of data-model integration requires investment in accessible, scalable, and transparent tools that integrate the expertise of the whole community, including both modelers and empiricists. This roadmap focuses on five key opportunities for community tools: the underlying foundations of community cyberinfrastructure; data ingest; calibration of models to data; model-data benchmarking; and data assimilation and ecological forecasting. This community-driven approach is a key to meeting the pressing needs of science and society in the 21st century.
MeSH term(s)	Ecosystem ; Forecasting ; Models, Theoretical
Language	English
Publishing date	2020-11-06
Publishing country	England
Document type	Journal Article
ZDB-ID	1281439-8
ISSN	1365-2486 ; 1354-1013
ISSN (online)	1365-2486
ISSN	1354-1013
DOI	10.1111/gcb.15409
Database	MEDical Literature Analysis and Retrieval System OnLINE

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