In her dissertation, Principal Research Scientist Sirpa Thessler from MTT (Agrifood Research Finland) combined field observations made in the lowland rainforests of the Amazonas region with satellite image analysis and was also able to predict the floristic variation of unexplored areas.
By knowing the differences in species composition between areas, conservation and land use can be planned and carried out effeciently. When the floristic variaton of the region is known, new conservation areas can be planned effectively to complement the existing ones.
INDICATOR SPECIES WERE OBSERVED IN THE FIELD
In her dissertation, Ms Thessler examined the field observations made by the University of Turku Amazon research group in the rainforests of Ecuador, Peru and Costa Rica and combined these with Landsat satellite images taken from the same areas.
The species richness in the rainforests is immense, for which reason observations in the field are practically always limited in certain indicator species. They provide information about the environmental variation of the region, such as the nutrient content and humidity of soil, thus also describe the general patterns of flora .
In Thessler’s study, the indicator species included grass- and shrub-like Melastomataceae species and ferns in the understorey as well as tree and palm species in the canopy layer.
PIXEL VALUES REVEAL VARIATION
Field observations on hundreds of plant species were statistically summarised in three dimensions, in order to be able to present the satellite image based predictions of compositional variation in a single map. In addition various vegetation types were classified from the satellite images.
“I found a statistical association between the field observations and the pixel values of the satellite images, which led me to conclude that the images are indicative of the floristic patterns,” Ms Thessler states.
The researcher was equipped with field observations from a combined area of 47 square kilometres: based on these, she was able to predict the flora of an area of 4,100 square kilometres. Thessler points out that by satellite images we do not achieve a level of accuracy equal to field observations, but in rainforests with practically impenetrable forest they constitute one possible method.
“Surveying the flora of rainforests by means of field observations is difficult, time consuming and expensive. Even a rough estimate made with the aid of satellite images is better than nothing,” Ms Thessler sums up.
NEIGHBOURS PROVIDE RELIABLE INFORMATION
Sirpa Thessler’s dissertation also revealed that the “k Nearest Neighbour” method used for forest inventories in Finland and several other European countries also provides reliable information when it comes to tropical rainforests.
The method involves the examination of a single pixel in a satellite image and searching the pixels, named neighbours, that are closest in their spectral values and from which field observations are available. The letter “k” refers to the number of neighbours. Based on the known neighbours, the floristic class, for example, or another indicator of the species composition can be predicted for the pixels over the study area.
“The method seems quite promising. It produced good accuracies in predicting the floristic variation of a rainforest,” Thessler relates.
Ulla Jauhiainen | alfa
Oasis of life in the ice-covered central Arctic
24.10.2016 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung
Receding glaciers in Bolivia leave communities at risk
20.10.2016 | European Geosciences Union
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
24.10.2016 | Earth Sciences
24.10.2016 | Life Sciences
24.10.2016 | Physics and Astronomy