Continuous Detection of Small-Scale Changes in Scots Pine Dominated Stands Using Dense Sentinel-2 Time Series

Climate change and severe extreme events, i.e., changes in precipitation and higher drought frequency, have a large impact on forests. In Poland, particularly Norway spruce and Scots pine forest stands are exposed to disturbances and have, thus experienced changes in recent years. Considering that Scots pine stands cover approximately 58% of forests in Poland, mapping these areas with an early and timely detection of forest cover changes is important, e.g., for forest management decisions. A cost-efficient way of monitoring forest changes is the use of remote sensing data from the Sentinel-2 satellites. They monitor the Earth’s surface with a high temporal (2–3 days), spatial (10–20 m), and spectral resolution, and thus, enable effective monitoring of vegetation. In this study, we used the dense time series of Sentinel-2 data from the years 2015–2019, (49 images in total), to detect changes in coniferous forest stands dominated by Scots pine. The simple approach was developed to analyze the spectral trajectories of all pixels, which were previously assigned to the probable forest change mask between 2015 and 2019. The spectral trajectories were calculated using the selected Sentinel-2 bands (visible red, red-edge 1–3, near-infrared 1, and short-wave infrared 1–2) and selected vegetation indices (Normalized Difference Moisture Index, Tasseled Cap Wetness, Moisture Stress Index, and Normalized Burn Ratio). Based on these, we calculated the breakpoints to determine when the forest change occurred. Then, a map of forest changes was created, based on the breakpoint dates. An accuracy assessment was performed for each detected date class using 861 points for 46 classes (45 dates and one class representing no changes detected). The results of our study showed that the short-wave infrared 1 band was the most useful for discriminating Scots pine forest stand changes, with the best overall accuracy of 75%. The evaluated vegetation indices underperformed single bands in detecting forest change dates. The presented approach is straightforward and might be useful in operational forest monitoring.

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Monitoring of water table dynamics in peatlands with OPTRAM: Towards globally applicable algorithms in Google Earth Engine using Landsat and Sentinel-2

10.5194/egusphere-egu21-4698 ◽

2021 ◽

Author(s):

Iuliia Burdun ◽

Michel Bechtold ◽

Viacheslav Komisarenko ◽

Annalea Lohila ◽

Elyn Humphreys ◽

...

Keyword(s):

Time Series ◽

Water Table ◽

Input Data ◽

Short Wave ◽

Google Earth ◽

Google Earth Engine ◽

Short Wave Infrared ◽

Northern Peatlands ◽

Sentinel 2

<p>Fluctuations of water table depth (WTD) affect many processes in peatlands, such as vegetation development and emissions of greenhouse gases. Here, we present the OPtical TRApezoid Model (OPTRAM) as a new method for satellite-based monitoring of the temporal variation of WTD in peatlands. OPTRAM is based on the response of short-wave infrared reflectance to the vegetation water status. For five northern peatlands with long-term in-situ WTD records, and with diverse vegetation cover and hydrological regimes, we generate a suite of OPTRAM index time series using (a) different procedures to parametrise OPTRAM (peatland-specific manual vs. globally applicable automatic parametrisation in Google Earth Engine), and (b) different satellite input data (Landsat vs. Sentinel-2). The results based on the manual parametrisation of OPTRAM indicate a high correlation with in-situ WTD time-series for pixels with most suitable vegetation for OPTRAM application (mean Pearson correlation of 0.7 across sites), and we will present the performance differences when moving from a manual to an automatic procedure. Furthermore, for the overlap period of Landsat and Sentinel-2, which have different ranges and widths of short-wave infrared bands used for OPTRAM calculation, the impact of the satellite input data to OPTRAM will be analysed. Eventually, the challenge of merging different satellite missions in the derivation of OPTRAM time series will be explored as an important step towards a global application of OPTRAM for the monitoring of WTD dynamics in northern peatlands.</p>

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Dissolved Organic Nitrogen Concentrations and Ratios of Dissolved Organic Carbon to Dissolved Organic Nitrogen in Throughfall and Soil Waters in Norway Spruce and Scots Pine Forest Stands Throughout Norway

Water Air & Soil Pollution ◽

10.1007/s11270-009-0239-x ◽

2009 ◽

Vol 210 (1-4) ◽

pp. 171-186 ◽

Cited By ~ 14

Author(s):

Yijie Wu ◽

Nicholas Clarke ◽

Jan Mulder

Keyword(s):

Organic Carbon ◽

Dissolved Organic Carbon ◽

Norway Spruce ◽

Scots Pine ◽

Dissolved Organic Nitrogen ◽

Organic Nitrogen ◽

Pine Forest ◽

Forest Stands ◽

Nitrogen Concentrations ◽

Scots Pine Forest

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Similarities in ground- and satellite-based NDVI time series and their relationship to physiological activity of a Scots pine forest in Finland

Remote Sensing of Environment ◽

10.1016/j.rse.2004.07.006 ◽

2004 ◽

Vol 93 (1-2) ◽

pp. 225-237 ◽

Cited By ~ 94

Author(s):

Quan Wang ◽

John Tenhunen ◽

Nguyen Quoc Dinh ◽

Markus Reichstein ◽

Timo Vesala ◽

...

Keyword(s):

Time Series ◽

Scots Pine ◽

Physiological Activity ◽

Pine Forest ◽

Ndvi Time Series ◽

Scots Pine Forest

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Analysis of natural regeneration of Scots pine forest in the high Campine after a fire

Silva Gandavensis ◽

10.21825/sg.v53i0.912 ◽

1988 ◽

Vol 53 ◽

Cited By ~ 1

Author(s):

N. Lust

Keyword(s):

Scots Pine ◽

Natural Regeneration ◽

Fire Regime ◽

Pine Forest ◽

Seed Supply ◽

Regeneration Period ◽

The Social ◽

Short Period ◽

Fire Area ◽

Scots Pine Forest

The study deals with the spontaneous resettlement of a fire area, after destruction of 600 ha Scots pine forest. The following items have been examined in particular: the composition of the tree species, the duration of the regeneration period, the influence of the parent stand, the exposition, the slope, the treatment, the fire regime and the social differentiation. The resettlement took place very quickly and over a very short period. Birch and Scots pine take up 95 % of the stem number. The regeneration result is precarious, yet mostly good. The parent stand is favourable both to seed supply and to microclimate, but only over a short distance. The Scots pine prefers more open and dry areas, whereas birch needs more humidity. Practice has shown that natural regeneration of Scots pine stands is possible. The forest treatment, however, is very important. It determines not only the immediate result of the regeneration, but also the composition and the structure of the future stand.

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Exchange of trace gases between soils and the atmosphere in Scots pine forest ecosystems of the northeastern German lowlands

Forest Ecology and Management ◽

10.1016/s0378-1127(01)00725-3 ◽

2002 ◽

Vol 167 (1-3) ◽

pp. 123-134 ◽

Cited By ~ 87

Author(s):

K Butterbach-Bahl ◽

L Breuer ◽

R Gasche ◽

G Willibald ◽

H Papen

Keyword(s):

Scots Pine ◽

Forest Ecosystems ◽

Trace Gases ◽

Pine Forest ◽

Scots Pine Forest

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Impacts of summer water limitation on the carbon balance of a Scots pine forest in the southern upper Rhine plain

Agricultural and Forest Meteorology ◽

10.1016/j.agrformet.2008.06.008 ◽

2008 ◽

Vol 148 (11) ◽

pp. 1815-1826 ◽

Cited By ~ 22

Author(s):

Jutta Holst ◽

Romain Barnard ◽

Elke Brandes ◽

Nina Buchmann ◽

Arthur Gessler ◽

...

Keyword(s):

Scots Pine ◽

Carbon Balance ◽

Pine Forest ◽

Water Limitation ◽

Scots Pine Forest ◽

Upper Rhine

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Methodological development for combined analysis of S and 35S in a Scots pine forest study

Communications in Soil Science and Plant Analysis ◽

10.1080/00103629209368688 ◽

1992 ◽

Vol 23 (13-14) ◽

pp. 1575-1589 ◽

Cited By ~ 2

Author(s):

A. P. Rowland ◽

A. F. Harrison ◽

V. H. Kennedy ◽

J. N. Cape

Keyword(s):

Scots Pine ◽

Pine Forest ◽

Methodological Development ◽

Combined Analysis ◽

Scots Pine Forest

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Soil Solution Response to Nitrogen and Magnesium Application in a Scots Pine Forest

Soil Science Society of America Journal ◽

10.2136/sssaj2001.1812 ◽

2001 ◽

Vol 65 (6) ◽

pp. 1812-1823 ◽

Cited By ~ 13

Author(s):

Live S. Vestgarden ◽

Gunnar Abrahamsen ◽

Arne O. Stuanes

Keyword(s):

Soil Solution ◽

Scots Pine ◽

Pine Forest ◽

Scots Pine Forest

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Modelling short-term variability in carbon and water exchange in a temperate Scots pine forest

Earth System Dynamics ◽

10.5194/esd-6-485-2015 ◽

2015 ◽

Vol 6 (2) ◽

pp. 485-503 ◽

Cited By ~ 6

Author(s):

M. H. Vermeulen ◽

B. J. Kruijt ◽

T. Hickler ◽

P. Kabat

Keyword(s):

Water Uptake ◽

Scots Pine ◽

Water Exchange ◽

Carbon Sink ◽

Pine Forest ◽

Temperature Threshold ◽

Water Fluxes ◽

Local Data ◽

Deep Soil ◽

Scots Pine Forest

Abstract. The vegetation–atmosphere carbon and water exchange at one particular site can strongly vary from year to year, and understanding this interannual variability in carbon and water exchange (IAVcw) is a critical factor in projecting future ecosystem changes. However, the mechanisms driving this IAVcw are not well understood. We used data on carbon and water fluxes from a multi-year eddy covariance study (1997–2009) in a Dutch Scots pine forest and forced a process-based ecosystem model (Lund–Potsdam–Jena General Ecosystem Simulator; LPJ-GUESS) with local data to, firstly, test whether the model can explain IAVcw and seasonal carbon and water exchange from direct environmental factors only. Initial model runs showed low correlations with estimated annual gross primary productivity (GPP) and annual actual evapotranspiration (AET), while monthly and daily fluxes showed high correlations. The model underestimated GPP and AET during winter and drought events. Secondly, we adapted the temperature inhibition function of photosynthesis to account for the observation that at this particular site, trees continue to assimilate at very low atmospheric temperatures (up to daily averages of −10 °C), resulting in a net carbon sink in winter. While we were able to improve daily and monthly simulations during winter by lowering the modelled minimum temperature threshold for photosynthesis, this did not increase explained IAVcw at the site. Thirdly, we implemented three alternative hypotheses concerning water uptake by plants in order to test which one best corresponds with the data. In particular, we analyse the effects during the 2003 heatwave. These simulations revealed a strong sensitivity of the modelled fluxes during dry and warm conditions, but no single formulation was consistently superior in reproducing the data for all timescales and the overall model–data match for IAVcw could not be improved. Most probably access to deep soil water leads to higher AET and GPP simulated during the heatwave of 2003. We conclude that photosynthesis at lower temperatures than assumed in most models can be important for winter carbon and water fluxes in pine forests. Furthermore, details of the model representations of water uptake, which are often overlooked, need further attention, and deep water access should be treated explicitly.

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