September-December 2019: Investigating patterns of ecosystem properties by using local measurements and remote sensing indices
This stage of the project was meant to use collected data from the field to explore patterns of variability in several key ecosystem properties. We also attempted to use measurements from the field (snow dynamics and productivity) to validate several indices obtained by remote sensing techniques.
Our results showed that local measurements of temperature and other properties (soil chemistry, primary productivity, litter decomposition) are povital for capturing spatial heteroteneity of ecosystem properties in mountain environments.
The results of comparisons of local vs. remotely derived indices of snow dynamics and productivity further indicate that studies seeking to predict the response of ecosystems to climate change would greatly benefit from the use of freely accessible satellite images at large spatial and temporal scales.
July-August 2019: Assembling the database of ecosystem properties
Database development was based on several key procedures that necessitated various types of labor:
- integration of thousands of soil temperature values recorded with loggers at each two hours in 28 sites, into several bioclimatic indices (using R scripts)
- calculation of the tea mass lost (by weighting the remaining material in the tea bags)
- preparation of biomass and soil samples (powder) for laboratory analyses (i.e. total organic carbon, nitrogen, phosphorus, soil pH)
June 2019: Revisiting the long-term monitoring sites in the Romanian Carpathians
The field work was done in the second year in order to accomplish several key tasks of the proiect:
- ensure continuous functioning of the monitoring sites by field relocation and replacement of batteries for devices (loggers)
- download soil temperature recordings
- fill incomplete data, e.g. collecting soil samples from several sites
- retrieve buried Rooibos tea bags from previous year
- instrumentalize new monitoring sites in the Parâng Master site
All sites have been relocated with high precision and the instruments were collected in good working order. However, one site in lower elevation from the Parâng Mts. was vandalized and both data loggers were lost. Therefore, we successfully collected data from 28 sites.
October 2018: Database development – mapping of the long-term monitoring sites
July-August 2018: Instrumentation of the MEMOIRE monitoring sites
In order to cover contrasting habitats along elevational gradients, we succeeded to install new monitoring sites in three mountain ranges of the Romanian Carpathians during the summer of 2018:
- Parâng Mountains (14 sites) – master site
- Rodna Mountains (11 sites)
- Apuseni Mountains (4 sites)
The sampling design in each range followed a specific approach which allowed us to choose a broad spectrum of ecosystem types, from around 1000m to above 2200m. The community types included meadows dominated by Agrostis tenuis and Festuca rubra (at lower altitudes), Nardus stricta and F. nigrescens (at intermediate elevations), and Carex curvula and Juncus trifidus (at high altitudes, above 2000m).
Important sites for high altitudes include the Gărgălău peak in Rodna Mts., Urdele and Mohorul peaks in Parâng, whereas in Muntele Mare was representative for the Apuseni range.
The field work consisted in the following operations:
- choosing the right location for sites to avoid elements that could disturb the following remote sensing analyses (trees, forest margins etc.). Therefore, the sites were chosen to be as even as possible in terms of vegetation type.
- making the relevee to record data on species composition and abundance (species diversity).
- installing two HOBO data loggers to record temperature at each 2 hours. We decided to install two replicates in order to make sure that any issue (e.g. battery loss, lost logger) would not affect data recording.
- installing 5 teabags of Roiboos tea, which were weighted prior to the field campaigns for estimating litter decomposition in the soil.
- collecting soil cores for chemical analyses (in Parâng – 14 sites).
- collecting soil cores to extract roots under tap water (in Parâng).
Back from the field, the sampled material was handled and dried at room temperature:
- problematic plant specimens were put into press to later identify.
- soil samples were sieved using a 2mm sieve and dried.
- roots were extracted from the soil cores, outside under a tap water facility.
- live (green) biomass was separated from the dry, as well as from the non-vascular species, and weighted using a balance.
July 2018: the Parâng Master Site
We initiated a master site in the Parâng Mountains from which researchers will better benefit in terms of data variety. In addition to micro-climate measurements and other ecosystem parameters measured in MEMOIRE, here we have collected samples of soil and plant roots, which could provide important information on different relationships between ecosystem properties and climate. We are committed to extend our network of researchers and partnerships, therefore the Parâng Master Site will contribute to a better understanding of the important changes taking place.
Through its mission and long-term observations, MEMOIRE project will be crucial for monitoring climate change in the Romanian Carpathians.