Remote sensing in inventory of high altitude pastures of the eastern Tibetan Plateau

The animal husbandry practised on high altitude pastures of the eastern Tibetan Plateau is based on the use of natural pastures. The livestock consists of yaks, sheep and horses. During the recent decades the number of animals has increased in the Dzoge study area, which is located in the north western part of the Sichuan province at an altitude of 2800-4000 meters. Most of Dzoge is treeless grassland with large peat land areas. The remote sensing and Geographical Information System (GIS) methods combined with the conventional pasture mapping provide a methodology to make a cost effective and reliable inventory of large areas. Providing accurate data about the quality and quantity of pastures and also of the amount of natural forage resources promotes sustainable use of the pastures. Two field trips were made to Dzoge. Random test plots (186) covering the main vegetation types in the research area were selected. The Landsat TM image is the remote sensing data in used this study. The image classification was done in the ERMapper program. The final map producing and the accuracy assessment were performed in the ArcGIS program. The Landsat TM image proved to be a useful data source in the mapping of pastures in the Dzoge area. The main vegetation classes were classified accurately. The estimations of the biomass of different vegetation types were made. Elevation differences were relatively small and the shadows on the slopes did not affect the classification significantly

Remote sensing in inventory of high altitude pastures of the eastern Tibetan Plateau

The animal husbandry practised on high altitude pastures of the eastern Tibetan Plateau is based on the use of natural pastures. The livestock consists of yaks, sheep and horses. During the recent decades the number of animals has increased in the Dzoge study area, which is located in the north western part of the Sichuan province at an altitude of 2800-4000 meters. Most of Dzoge is treeless grassland with large peat land areas. The remote sensing and Geographical Information System (GIS) methods combined with the conventional pasture mapping provide a methodology to make a cost effective and reliable inventory of large areas. Providing accurate data about the quality and quantity of pastures and also of the amount of natural forage resources promotes sustainable use of the pastures. Two field trips were made to Dzoge. Random test plots (186) covering the main vegetation types in the research area were selected. The Landsat TM image is the remote sensing data in used this study. The image classification was done in the ERMapper program. The final map producing and the accuracy assessment were performed in the ArcGIS program. The Landsat TM image proved to be a useful data source in the mapping of pastures in the Dzoge area. The main vegetation classes were classified accurately. The estimations of the biomass of different vegetation types were made. Elevation differences were relatively small and the shadows on the slopes did not affect the classification significantly

Geoenergy permit practices in Finnish municipalities - Challenges with good governance

The rapidly increasing renewable energy installations are often controlled through permit schemes, and good permit practices need to be developed for energy policy planning purposes. In Finland ground heat exchangers (GHEs) for geoenergy systems commonly need a permit from the municipal building control. We examine this municipal permit scheme, its functionality in groundwater protection and compatibility with the principles of good governance. Our data consists of permit and notification documents, interviews of building control officials and municipal regulations and instructions from nine municipalities in Southwest Finland. Similar studies based on empirical data have not been conducted earlier on geoenergy permit schemes. Despite common legislation there were many differences between municipalities in the application-stage permit practices, municipal regulations, supervision and quality control of GHEs. Well-functioning permit practices safeguard both the public and the neighbors’ interests, promote groundwater protection and support the client with quality control.</p

Permafrost degradation at two monitored palsa mires in north-west Finland

Palsas and peat plateaus are expected to disappear from many regions, including Finnish Lapland. However, detailed long-term monitoring data of the degradation process on palsas are scarce. Here, we present the results of the aerial photography time series analysis (1959–2021), annual real-time kinematic (RTK) GNSS and active layer monitoring (2007–2021), and annual unoccupied aerial system surveys (2016–2021) at two palsa sites (Peera and Laassaniemi, 68∘ N) located in north-west Finland. We analysed temporal trends of palsa degradation and their relation to climate using linear regression. At both sites, the decrease in palsa area by −77 % to −90 % since 1959 and height by −16 % to −49 % since 2007 indicate substantial permafrost degradation throughout the study periods. The area loss rates are mainly connected to winter air temperature changes at Peera and winter precipitation changes at Laassaniemi. The active layer thickness (ALT) has varied annually between 2007 and 2021 with no significant trend and is related mainly to the number of very warm days during summer, autumn rainfall of previous year, and snow depths at Peera. At Laassaniemi, the ALT is weakly related to climate and has been decreasing in the middle part of the palsa during the past 8 years despite the continuous decrease in palsa volume. Our findings imply that the ALT in the inner parts of palsas do not necessarily reflect the overall permafrost conditions and underline the importance of surface position monitoring alongside the active layer measurements. The results also showed a negative relationship between the ALT and snow cover onset, indicating the complexity of climate–permafrost feedbacks in palsa mires

Undrained peatland areas disturbed by surrounding drainage : A large scale GIS analysis in Finland with a special focus on aapa mires

Half of the Finnish peatland area is drained for forestry. The remaining undrained peatlands are not all pristine, because surrounding drainage may disturb their hydrology. This concerns especially aapa mires, which are dependent on hydrological connections to their upper catchments. We investigated the amount and sizes of Finnish undrained peatlands, the drainage state of their margins, and the naturalness of aapa mires in large (> 50 ha) undrained peatland areas, using a GIS analysis based on digital map data, aerial images and an elevation model. The results show that a majority (66.7 % of count, 84.7 % of area) of undrained peatland areas have at least partly drained margins. Drainage activities commonly disturb minerotrophic water discharge to aapa mires. In the middle boreal zone, on average 41.6 % (median 42.8 %) of the catchment area of aapa mires is such that hydrological connection with the mire is disturbed by intervening drainage. In the southern boreal zone, the figure is 25.1 % (median 16.1 %), and in the southern part of the northern boreal zone 24.2 % (median 9.9 %). Possible implications of the disturbances include tree encroachment, hummock formation and fen–bog transition, which is likely to cause a loss of biodiversity but could potentially increase peat growth and carbon sequestration

Effect of canopy structure on the performance of tree mapping methods in urban parks

Urban forests consist of patches of recreational areas, parks, and single trees on roadsides and other forested urban areas. Large number of tree species and heterogeneous growing conditions result in diverse canopy structure. High variation can be found both at level of single tree crowns and in canopy characteristics of larger areas. As urban forests are typically managed with small-scale, even tree-level operations, there is a need for detailed forest information. In this study, the effect of varying canopy conditions was tested on nine individual tree detection (ITD) methods. All methods utilized airborne laser scanning (ALS)-derived canopy height models (CHM) and different modifications of watershed segmentation (WS). The performance of mapping methods was compared in three strata with varying mean height and canopy cover. The results showed considerable variation between the methods when tested in varying canopy conditions. Especially, presence of large broadleaved trees affected the accuracy of detecting individual trees. The best performing methods for the three strata were G0.7, F2 and Gadapt. The areas with low canopy cover turned out problematic for all ITD methods tested as co-occurrence of small trees and large deciduous trees affected the accuracy significantly. Overall, The results show that stratification can be used to enhance the quality of ITD in urban park areas. However, heterogeneous canopy structure and varying growth patterns typical for urban parks lower the accuracy of tree detection. Also, according to our results we suggest that canopy height and canopy cover alone are insufficient attributes for stratifying urban canopy conditions.Peer reviewe