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Postdoctoral Project 2

PROJECT TITLE

The impact of recent climate change on the ecological productivity of forests in Romania

PROJECT ACRONYM

CLIMFOREST

PROJECT CODE

PN-III-P1-1.1-PD-2019-0064

FUNDING SOURCE

The Executive Agency for Higher Education, Research, Development and Innovation Funding

RESEARCH PROJECT DESCRIPTION (ABSTRACT)

Forests are among the world’s most important terrestrial ecological systems, considering the wide range of ecosystem functions, goods and services they provide for the environment and humanity. However, these ecological attributes of forests have been intensely disrupted in numerous regions worldwide under the pressure of climate change and anthropogenic activities. Climate change has become an increasingly apparent threat to these ecosystems, also in Romania, considering the recent changes in climatic conditions recorded in our country, which were confirmed by many specialized studies. Given the lack of interdisciplinary research in this respect, this study aims to conduct the first-ever analysis of the potential effects of climate change on forest productivity countrywide. The approach, based on the analysis of complex geospatial data, aims to test the hypothesis of climate change impact on forest productivity, an ecological feature that is essential to maintaining the forests’ health and ecosystem services. Therefore, the project will use various national data, classified as climatic (values of temperature, precipitation, evapotranspiration etc.) and satellite (Landsat images, from which representative ecometric data will be extracted for forest vegetation density, biomass and net primary productivity) data. The two categories of necessary data will be purchased for the 1987–2016 period and will be processed using complex geostatistical techniques (trends, linear regressions, bootstrapping etc.), which were selected so as to capture climate and ecological changes in Romania, as well as statistical causality relationships between climate and forest productivity over the past three decades. The results of this study will be useful primarily for the various governmental strategies focusing on protecting these terrestrial ecosystems, fighting climate change or mitigating the effects of climate change in Romania.

THE PROJECT’S OBJECTIVES

  Acquisition of interannual climatic and satellite data in Romania for the 1987–2016 period, necessary to test the hypothesis of the recent climate change impact on forest productivity countrywide;
  Geostatistical processing of trends in forest vegetation density in Romania, in relation to the trends of the main climatic parameters over the past three decades;
Geostatistical processing of trends in forest biomass in Romania, in relation to the trends of the main climatic parameters over the past three decades;
Geostatistical processing of trends in net primary productivity of forests in Romania, in relation to the trends of the main climatic parameters over the past three decades;
Raising awareness on the necessity of interdisciplinary scientific investigations of this important ecoclimatic issue in Romania’s scientific/political spheres by disseminating the study’s results.

PROJECT RESULTS

The results highlighted recent important changes in forest productivity, which were investigated through ecological indicators of vegetation density (Normalized Difference Vegetation Index – NDVI) (1), above-ground live biomass (AGB) (2) and net primary productivity (NPP) (3). In terms of vegetation density (1), the results showed general greening (increasing NDVI) trends of forests nationally (65% of all NDVI changes), which were dominated by widespread positive NDVI trends in the Carpathians region. This general ecological dynamic suggests a possible enhancement in vegetation productivity in the country’s high-altitude areas. Contrasting browning (decreasing NDVI) trends were found for 35% of Romanian forestlands marked by NDVI changes, especially in the Extra-Carpathians (lowland) region, which indicates that in these cases forests were probably degraded or devitalized. However, the statistical significance of both greening and browning trends is limited across the country, which means that NDVI dynamics should be interpreted with caution.

Regarding biomass (2), a quantitative measure of forest productivity (t/ha/yr), findings revealed increasing (positive) and decreasing (negative) AGB trends that account for ~70% and 30%, respectively, of the countrywide AGB changes. However, it was found that about half (~48%) of all positive AGB trends are statistically significant, while negative AGB trends have a statistical confidence on only one-fifth (~21%) of their spatial footprint in Romania. Regionally, the AGB change pattern is not marked by obvious contrasting trends between Carpathian and Extra-Carpathian regions.

In terms of forest NPP (3), exploring the changes of this quantitative ecological indicator (t C/ha/yr) showed, surprisingly, almost exclusively increasing trends (99.6%) at the national level, statistically significant on a large scale across the country (~73% of all countrywide positive trends). These NPP changes reflect an intensification of carbon fluxes between countrywide forests and the atmosphere, and an increase in carbon storage capacity of Romanian forests, after 1987.

The analysis of the climate impact on forest vegetation state, performed through eco-climatic statistical correlations, revealed that recent warming is one of the driving forces of the general increases in forest productivity, probably due to lengthening of the vegetation growing season and to the increase in phenological (photosynthetic) activity. However, a generally moderate intensity of eco-climatic relationships was detected in Romania, which indicates an additional role of other non-climatic environmental factors (in the forest ecological dynamics) that were not explored in this research, but which could open new research directions in future ecological studies.

All these results of the project may be useful to various forestry stakeholders and policymakers operating regionally or centrally in Romania. For example, the various data resulting from this extensive countrywide research may be of interest, at regional level, to County Forestry Directorates, which work towards the sustainable management (protection, conservation, development, capitalization and rational use) of countrywide forests. At central level, the results can be a valuable informational support for current and future government strategies aimed at protecting and developing the national forest sector or at adapting forest ecosystems to the effects of current and future climate change.

PROJECT MANAGER AND HOST INSTITUTION

Name and surname: Prăvălie Remus
E-mail address: pravalie_remus@yahoo.com
Institution name: University of Bucharest
Institution address: Sos. Panduri, 90–92, 050663, 5th District, Bucharest, Romania

PROJECT MENTOR

Prof. Dr. Bandoc Georgeta

SCIENTIFIC DELIVRABLES (2020-2022)

Articles directly related to the project theme:

  • Prăvălie, R., Sîrodoev, I., Nita, I.A., Patriche, C., Dumitrașcu, M., Roșca, B., Tişcovschi, A., Bandoc, G., Săvulescu., I., Mănoiu, V., Birsan. M.V., 2022. “NDVI-based ecological dynamics of forest vegetation and its relationship to climate change in Romania during 1987–2018”. Ecological Indicators 136, https://doi.org/10.1016/j.ecolind.2022.108629, Impact Factor (IF) 6.3, Article Influence Score (AIS) 1, red zone (Q1 category in Web of Science);
  • Prăvălie, R., Niculiță, M., Roșca, B., Patriche, C., Dumitrașcu, M., Marin, G., Nita, I.A., Bandoc, G., Birsan, M.V., 2023.  “Modelling
    forest biomass dynamics in relation to climate change in Romania using complex data and machine learning algorithms”. Stochastic Environmental Research and Risk Assessment 37, 1669–1695, https://doi.org/10.1007/s00477-022-02359-z, IF 3.8, AIS 0.6, red zone (Q1);
  • Prăvălie, R., Niculiță, M., Roșca, B., Marin, G., Dumitrașcu, M., Patriche, C., Birsan, M.V., Nita, I.A., Tișcovschi, A., Sîrodoev, I.,
    Bandoc, G., 2023. Machine learning-based prediction and assessment of recent dynamics of forest net primary productivity in Romania”. Journal of Environmental Management 334, https://doi.org/10.1016/j.jenvman.2023.117513, IF 8.9, AIS 1.1, red zone (Q1).

Articles indirectly related to the project theme:

  • Prăvălie, R., 2021. “Exploring the multiple land degradation pathways across the planet”. Earth Science Reviews 220, https://doi.org/10.1016/j.earscirev.2021.103689, IF 12, AIS 3.9, red zone (Q1);
  • Prăvălie, R., Nita, I.A., Patriche, C., Niculiță, M., Birsan, M.V., Roșca, B., Bandoc, G., 2021. “Global changes in soil organic carbon and implications for land degradation neutrality and climate stability”. Environmental Research 201, https://doi.org/10.1016/j.envres.2021.111580, IF 8.4, AIS 1.4, red zone (Q1).

International conferences directly or indirectly related to the project theme:

  • Prăvălie, R., 2020. “Forest perturbations across the planet. A major pathway of global land degradation”. International Conference “Dimitrie Cantemir”, 40th Edition, October 24, Iași, Romania;
  • Prăvălie, R., Bandoc, G., 2020. “Spatio-temporal trends in land susceptibility to degradation in Romania due to climate change, vegetation degradation and anthropogenic pressures”. International Conference “Present Environment and Sustainable Development”, 15th Edition, November 21, Iaşi, Romania;
  • Prăvălie, R., Bandoc, G., 2021. “Analysis of forest ecological changes in Romania based on detecting recent trends in Normalized Difference Vegetation Index”. “9th Annual International Conference on Ecology, Ecosystems and Climate Change”, 12–15 July, Athens, Greece;
  • Prăvălie, R., 2021. “Recent impact of climate change on forest productivity in Romania”. “27th International Conference on “Agriculture, Biological and Environmental Sciences” (MABES-21)”, August 11–13, Barcelona, Spain (the presentation was awarded the prize for the best oral presentation in this international conference);
  • Prăvălie, R., Bandoc, G., 2021. “Detecting land-atmosphere carbon fluxes at global scale after 2001”. The 2nd International Conference “Geographical Sciences and Future of Earth”, November 12, Bucharest, Romania;
  • Prăvălie, R., Bandoc, G., 2022. “Exploring forest biomass changes in Romania in the last three decades”. International Conference on Forest Ecosystem Carbon Dynamics and Climate Change, January 14–15, Zurich, Switzerland;
  • Prăvălie, R., Niculiță, M., Roșca, B., Patriche, C., Bandoc, G., 2022. “Examining trends in forest above-ground live biomass in Romania after 1987”. International Conference “Present Environment and Sustainable Development”, 17th Edition, June 3–4, Iaşi, Romania.

SCIENTIFIC REPORT 2020

SCIENTIFIC REPORT 2021

SCIENTIFIC REPORT 2022