Erasmi, Stefan

[["dc.bibliographiccitation.firstpage","1319"],["dc.bibliographiccitation.issue","5"],["dc.bibliographiccitation.journal","Biogeosciences"],["dc.bibliographiccitation.lastpage","1333"],["dc.bibliographiccitation.volume","15"],["dc.contributor.author","Klinge, Michael"],["dc.contributor.author","Dulamsuren, Choimaa"],["dc.contributor.author","Erasmi, Stefan"],["dc.contributor.author","Karger, Dirk Nikolaus"],["dc.contributor.author","Hauck, Markus"],["dc.date.accessioned","2019-07-09T11:45:23Z"],["dc.date.accessioned","2020-05-11T13:15:36Z"],["dc.date.available","2019-07-09T11:45:23Z"],["dc.date.available","2020-05-11T13:15:36Z"],["dc.date.issued","2018"],["dc.description.abstract","In northern Mongolia, at the southern boundary of the Siberian boreal forest belt, the distribution of steppe and forest is generally linked to climate and topography, making this region highly sensitive to climate change and human impact. Detailed investigations on the limiting parameters of forest and steppe in different biomes provide necessary information for paleoenvironmental reconstruction and prognosis of potential landscape change. In this study, remote sensing data and gridded climate data were analyzed in order to identify main distribution patterns of forest and steppe in Mongolia and to detect environmental factors driving forest development. Forest distribution and vegetation vitality derived from the normalized differentiated vegetation index (NDVI) were investigated for the three types of boreal forest present in Mongolia (taiga, subtaiga and forest–steppe), which cover a total area of 73 818 km2. In addition to the forest type areas, the analysis focused on subunits of forest and nonforested areas at the upper and lower treeline, which represent ecological borders between vegetation types. Climate and NDVI data were analyzed for a reference period of 15 years from 1999 to 2013. The presented approach for treeline delineation by identifying representative sites mostly bridges local forest disturbances like fire or tree cutting. Moreover, this procedure provides a valuable tool to distinguish the potential forested area. The upper treeline generally rises from 1800 m above sea level (a.s.l.) in the northeast to 2700 m a.s.l. in the south. The lower treeline locally emerges at 1000 m a.s.l. in the northern taiga and rises southward to 2500 m a.s.l. The latitudinal gradient of both treelines turns into a longitudinal one on the eastern flank of mountain ranges due to higher aridity caused by rain-shadow effects. Less productive trees in terms of NDVI were identified at both the upper and lower treeline in relation to the respective total boreal forest type area. The mean growing season temperature (MGST) of 7.9–8.9 °C and a minimum MGST of 6 °C are limiting parameters at the upper treeline but are negligible for the lower treeline. The minimum of the mean annual precipitation (MAP) of 230–290 mm yr−1 is a limiting parameter at the lower treeline but also at the upper treeline in the forest–steppe ecotone. In general, NDVI and MAP are lower in grassland, and MGST is higher compared to the corresponding boreal forest. One exception occurs at the upper treeline of the subtaiga and taiga, where the alpine vegetation consists of mountain meadow mixed with shrubs. The relation between NDVI and climate data corroborates that more precipitation and higher temperatures generally lead to higher greenness in all ecological subunits. MGST is positively correlated with MAP of the total area of forest–steppe, but this correlation turns negative in the taiga. The limiting factor in the forest–steppe is the relative humidity and in the taiga it is the snow cover distribution. The subtaiga represents an ecological transition zone of approximately 300 mm yr−1 precipitation, which occurs independently from the MGST. Since the treelines are mainly determined by climatic parameters, the rapid climate change in inner Asia will lead to a spatial relocation of tree communities, treelines and boreal forest types. However, a direct deduction of future tree vitality, forest composition and biomass trends from the recent relationships between NDVI and climate parameters is challenging. Besides human impact, it must consider bio- and geoecological issues like, for example, tree rejuvenation, temporal lag of climate adaptation and disappearing permafrost."],["dc.identifier.doi","10.5194/bg-15-1319-2018"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/15188"],["dc.identifier.scopus","2-s2.0-85043494931"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/65009"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/59218"],["dc.identifier.url","http://www.scopus.com/inward/record.url?eid=2-s2.0-85043494931&partnerID=MN8TOARS"],["dc.language.iso","en"],["dc.relation.issn","1726-4189"],["dc.subject.ddc","550"],["dc.title","Climate effects on vegetation vitality at the treeline of boreal forests of Mongolia"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","2893"],["dc.bibliographiccitation.issue","10"],["dc.bibliographiccitation.journal","Biogeosciences"],["dc.bibliographiccitation.lastpage","2905"],["dc.bibliographiccitation.volume","12"],["dc.contributor.author","Klinge, Michael"],["dc.contributor.author","Bohner, J."],["dc.contributor.author","Erasmi, Stefan"],["dc.date.accessioned","2018-11-07T10:03:10Z"],["dc.date.accessioned","2020-05-11T13:23:57Z"],["dc.date.available","2018-11-07T10:03:10Z"],["dc.date.available","2020-05-11T13:23:57Z"],["dc.date.issued","2015"],["dc.description.abstract","Satellite images and digital elevation models provide an excellent database to analyze forest distribution patterns and forest limits in the mountain regions of semiarid central Asia on the regional scale. For the investigation area in the northern Tien Shan, a strong relationship between forest distribution and climate conditions could be found. Additionally areas of potential human impact on forested areas are identified at lower elevations near the edge of the mountains based on an analysis of the differences in climatic preconditions and the present occurrence of forest stands. The distribution of spruce (Picea schrenkiana) forests is hydrologically limited by a minimum annual precipitation of 250 mm and thermally by a minimum monthly mean temperature of 5 degrees C during the growing season. While the actual lower forest limit increases from 1600 m a.s.l. (above sea level) in the northwest to 2600 m a.s.l. in the southeast, the upper forest limit rises in the same direction from 1800 m a.s.l. to 2900 m a.s.l.. In accordance with the main wind directions, the steepest gradient of both forest lines and the greatest local vertical extent of the forest belt of 500 to 600 m to a maximum of 900 m occur at the northern and western mountain fronts. The forests in the investigation area are strongly restricted to north-facing slopes, which is a common feature in semiarid central Asia. Based on the presumption that variations in local climate conditions are a function of topography, the potential forest extent was analyzed with regard to the parameters slope, aspect, solar radiation input and elevation. All four parameters showed a strong relationship to forest distribution, yielding a total potential forest area that is 3.5 times larger than the present forest remains of 502 km(2)."],["dc.identifier.doi","10.5194/bg-12-2893-2015"],["dc.identifier.isi","000356179300006"],["dc.identifier.scopus","2-s2.0-84930216355"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/65048"],["dc.identifier.url","http://www.scopus.com/inward/record.url?eid=2-s2.0-84930216355&partnerID=MN8TOARS"],["dc.language.iso","en"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.relation.eissn","1726-4170"],["dc.relation.issn","1726-4189"],["dc.title","Modeling forest lines and forest distribution patterns with remote-sensing data in a mountainous region of semiarid central Asia"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","55"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Forest Ecosystems"],["dc.bibliographiccitation.volume","8"],["dc.contributor.author","Klinge, Michael"],["dc.contributor.author","Dulamsuren, Choimaa"],["dc.contributor.author","Schneider, Florian"],["dc.contributor.author","Erasmi, Stefan"],["dc.contributor.author","Bayarsaikhan, Uudus"],["dc.contributor.author","Sauer, Daniela"],["dc.contributor.author","Hauck, Markus"],["dc.date.accessioned","2021-09-01T06:38:24Z"],["dc.date.accessioned","2022-06-29T13:24:59Z"],["dc.date.accessioned","2022-08-18T12:38:34Z"],["dc.date.available","2021-09-01T06:38:24Z"],["dc.date.available","2022-06-29T13:24:59Z"],["dc.date.available","2022-08-18T12:38:34Z"],["dc.date.issued","2021-08-10"],["dc.date.updated","2022-07-29T12:18:50Z"],["dc.description.abstract","Abstract\r\n \r\n Background\r\n Forest distribution in the forest-steppe of Mongolia depends on relief, permafrost, and climate, and is highly sensitive to climate change and anthropogenic disturbance. Forest fires and logging decreased the forest area in the forest-steppe of Mongolia. The intention of this study was to identify the geoecological parameters that control forest distribution and living-tree biomass in this semi-arid environment. Based on these parameters, we aimed to delineate the area that forest might potentially occupy and to analyse the spatial patterns of actual and potential tree biomass.\r\n \r\n \r\n Methods\r\n We used a combination of various geographic methods in conjunction with statistical analyses to identify the key parameters controlling forest distribution. In several field campaigns, we mapped tree biomass and ecological parameters in a study area within the Tarvagatai Nuruu National Park (central Mongolia). Forest areas, topographic parameters and vegetation indices were obtained from remote sensing data. Significant correlations between forest distribution and living-tree biomass on one hand, and topographic parameters, climate data, and environmental conditions on the other hand, were used to delineate the area of potential forest distribution and to estimate total living-tree biomass for this area.\r\n \r\n \r\n Results\r\n Presence of forest on slopes was controlled by the factors elevation, aspect, slope, mean annual precipitation, and mean growing-season temperature. Combining these factors allowed for estimation of potential forest area but was less suitable for tree-biomass delineation. No significant differences in mean living-tree biomass existed between sites exposed to different local conditions with respect to forest fire, exploitation, and soil properties. Tree biomass was reduced at forest edges (defined as 30 m wide belt), in small fragmented and in large forest stands. Tree biomass in the study area was 20 × 109 g (1,086 km2 forest area), whereas the potential tree biomass would reach up to 65 × 109 g (> 3168 km2).\r\n \r\n \r\n Conclusions\r\n The obtained projection suggests that the potential forest area and tree biomass under the present climatic and geoecological conditions is three times that of the present forest area and biomass. Forest fires, which mostly affected large forest stands in the upper mountains, destroyed 43% of the forest area and 45% of the living-tree biomass in the study area over the period 1986–2017."],["dc.identifier.citation","Forest Ecosystems. 2021 Aug 10;8(1):55"],["dc.identifier.doi","10.1186/s40663-021-00333-9"],["dc.identifier.pii","333"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/88925"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/111871"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/112963"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-455"],["dc.publisher","Springer Singapore"],["dc.relation.eissn","2197-5620"],["dc.rights.holder","The Author(s)"],["dc.subject","Biomass"],["dc.subject","Fire"],["dc.subject","Forest-steppe"],["dc.subject","Geoecological factors"],["dc.subject","Mongolia"],["dc.subject","Permafrost"],["dc.title","Geoecological parameters indicate discrepancies between potential and actual forest area in the forest-steppe of Central Mongolia"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.contributor.author","Klinge, Michael"],["dc.contributor.author","Dulamsuren, Choimaa"],["dc.contributor.author","Schneider, Florian Dirk"],["dc.contributor.author","Erasmi, Stefan"],["dc.contributor.author","Hauck, Markus"],["dc.contributor.author","Bayarsaikhan, Uudus"],["dc.contributor.author","Sauer, Daniela"],["dc.date.accessioned","2020-05-12T08:31:04Z"],["dc.date.available","2020-05-12T08:31:04Z"],["dc.date.issued","2020"],["dc.description.abstract","he Mongolian forest-steppe is highly sensitive to climate change and environmental impact. The intention of this study was to identify, which geoecological parameters control forest distribution and tree growth in this semi-arid environment, and to evaluate the actual and potential tree biomass. For this purpose, we applied a combination of tree biomass and soil mapping, remote sensing and climate data analysis to a study area in the northern Khangai Mountains, central Mongolia. Forests of different landscape units and site conditions generally showed minor differences in tree biomass. We found no significant correlation between tree biomass and NDVI (normalized differentiated vegetation index). Tree biomass was reduced at forest edges, in small fragmented forest stands of the steppe-dominated area, and in large forest stands, compared to all other forest units. The tree biomass of forests on slopes ranged between 25 and 380 Mg ha−1. The mean tree biomass in forests of 10–500 ha was 199–220 Mg ha−1, whereby tree biomass at the forest edges was 50–63 Mg ha−1 less than in the interior parts of the forests. The mean tree biomass of forests > 500 ha was 182 Mg ha−1, whereas that of forests < 10 ha in the steppe-dominated area was only around 142 Mg ha−1. Forests in alluvial plains had maximum tree biomasses of 440–688 Mg ha−1. In contrast to tree biomass, the spatial extension of forests showed distinct relationships with topographic and climatic parameters. Presence of forest was controlled by elevation (< 2600 m a.s.l.), aspect (no southern slopes below 2100 m a.s.l.), slope (< 25°), mean annual precipitation (160–340 mm) and mean growing season temperature (6.5–10.8 °C). The actual forests of the study area covered 1,086 km2. In 1986, prior to extensive forest fires, it was 1,898 km2. The actual tree biomass of 20 × 109 g represented 57 % of that in 1986. Modelling of the potential forest area resulted in 3,552 km2, with 65 × 109 g tree biomass (based on topographic parameters) and 3,113 km2 with 58 × 109 g tree biomass (based on climatic parameters), respectively. The modelled potential forest area was thus about three times the actual forest area."],["dc.identifier.doi","10.5194/bg-2020-13"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/65131"],["dc.language.iso","en"],["dc.title","Modelled potential forest area in the forest-steppe of central Mongolia is about three times of actual forest area"],["dc.type","preprint"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","14667"],["dc.bibliographiccitation.issue","10"],["dc.bibliographiccitation.journal","Biogeosciences Discussions"],["dc.bibliographiccitation.lastpage","14698"],["dc.bibliographiccitation.volume","11"],["dc.contributor.author","Klinge, Michael"],["dc.contributor.author","Bohner, J."],["dc.contributor.author","Erasmi, Stefan"],["dc.date.accessioned","2019-07-09T11:41:13Z"],["dc.date.accessioned","2020-05-11T13:27:00Z"],["dc.date.available","2019-07-09T11:41:13Z"],["dc.date.available","2020-05-11T13:27:00Z"],["dc.date.issued","2014"],["dc.description.abstract","Satellite images and digital elevation models provide an excellent database to analyze forest distribution patterns and forest limits in the mountain regions of semiarid central Asia on the regional scale. For the investigation area in the northern Tien Shan, a strong relationship between forest distribution and climate conditions could be found. Additionally areas of potential human impact on forested areas are identified at lower elevations near the edge of the mountains based on an analysis of the differences in climatic preconditions and the present occurrence of forest stands. The distribution of spruce (Picea schrenkiana) forests is hydrologically limited by a minimum annual precipitation of 250mm and thermally by a minimum monthly mean temperature of 5 C during the growing season. While the actual lower forest limit increases from 1600ma.s.l. (above sea level) in the northwest to 2600ma.s.l. in the southeast, the upper forest limit rises in the same direction from 1800ma.s.l. to 2900ma.s.l.. In accordance with the main wind directions, the steepest gradient of both forest lines and the greatest local vertical extent of the forest belt of 500 to 600m to a maximum of 900m occur at the northern and western mountain fronts. The forests in the investigation area are strongly restricted to north-facing slopes, which is a common feature in semiarid central Asia. Based on the presumption that variations in local climate conditions are a function of topography, the potential forest extent was analyzed with regard to the parameters slope, aspect, solar radiation input and elevation. All four parameters showed a strong relationship to forest distribution, yielding a total potential forest area that is 3.5 times larger than the present forest remains of 502 km2."],["dc.identifier.doi","10.5194/bgd-11-14667-2014"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/11846"],["dc.identifier.scopus","2-s2.0-84908010586"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/58374"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/65053"],["dc.identifier.url","http://www.scopus.com/inward/record.url?eid=2-s2.0-84908010586&partnerID=MN8TOARS"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","1810-6285"],["dc.rights","CC BY 3.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/3.0/"],["dc.title","Modelling forest lines and forest distribution patterns with remote sensing data in a mountainous region of semi-arid central Asia"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","Environmental Monitoring and Assessment"],["dc.bibliographiccitation.volume","193"],["dc.contributor.author","Erasmi, Stefan"],["dc.contributor.author","Klinge, Michael"],["dc.contributor.author","Dulamsuren, Choimaa"],["dc.contributor.author","Schneider, Florian"],["dc.contributor.author","Hauck, Markus"],["dc.date.accessioned","2021-04-14T08:29:08Z"],["dc.date.available","2021-04-14T08:29:08Z"],["dc.date.issued","2021"],["dc.identifier.doi","10.1007/s10661-021-08996-1"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/82809"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-399"],["dc.relation.eissn","1573-2959"],["dc.relation.issn","0167-6369"],["dc.title","Modelling the productivity of Siberian larch forests from Landsat NDVI time series in fragmented forest stands of the Mongolian forest-steppe"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.contributor.author","Klinge, Michael"],["dc.contributor.author","Dulamsuren, Choimaa"],["dc.contributor.author","Erasmi, Stefan"],["dc.contributor.author","Karger, Dirk Nikolaus"],["dc.contributor.author","Hauck, Markus"],["dc.date.accessioned","2020-05-12T08:31:18Z"],["dc.date.available","2020-05-12T08:31:18Z"],["dc.date.issued","2017"],["dc.description.abstract","n northern Mongolia, at the southern boundary of the Siberian boreal forest belt, the distribution of steppe and forest is generally linked to climate and topography, making this region highly sensible to climate change. Detailed investigations on the limiting parameters of forest and steppe occurrence in different ecozones provide necessary information for environmental modelling and scenarios of potential landscape change. In this study, remote sensing data and gridded climate data were analyzed in order to identify distribution patterns of forest and steppe in Mongolia and to detect driving ecological factors of forest occurrence and vulnerability against environmental change. With respect to anomalies in extreme years we integrated the climate and land cover data of a 15 year period from 1999–2013. Forest distribution and vegetation vitality derived from the normalized differentiated vegetation index (NDVI) were investigated for the three ecozones with boreal forest present in Mongolia (taiga, subtaiga, and forest-steppe). In addition to the entire ecozone areas, the analysis focused on different subunits of forest and non-forested areas at the upper and lower treeline, which represent ecological borderlines of site conditions. The total cover of boreal forest in Mongolia was estimated at 73 818 km². The upper treeline generally increases from 1800 m above sea level (a.s.l.) in the Northeast to 2700 m a.s.l. in the South. The lower treeline locally emerges at 1000 m a.s.l. in the northern taiga and is rising southward to 2500 m a.s.l. The latitudinal trend of both treelines turns into a longitudinal trend in the east of the mountains ranges due to more aridity caused by rain-shadow effects. Less vital trees were identified by NDVI at both, the upper and lower treeline in relation to the respective ecozone. The mean growing season temperature (MGST) of 7.9–8.9 °C and a minimum of 6 °C was found to be a limiting parameter at the upper treeline but negligible for the lower treeline and the total ecozones. The minimum of the mean annual precipitation (MAP) of 230–290 mm yr−1 is an important limiting factor at the lower treeline but at the upper treeline in the forest-steppe ecotone, too. In general, NDVI and MAP are lower in grassland, and MGST is higher compared to the forests in the same ecozone. An exception occurs at the upper treeline of the subtaiga and taiga, where the alpine vegetation is represented by meadow mixed with shrubs. Comparing the NDVI with climate data shows that increasing precipitation and higher temperatures generally lead to higher greenness in all ecological subunits. While the MGST is positively correlated with the MAP of the total ecozones of the forest-steppe, this correlation turns negative in the taiga ecozone. The subtaiga represents an ecological transition zone of approximately 300 mm yr−1 precipitation, which occurs independently from the MGST. Nevertheless, higher temperatures lead to higher vegetation vitality in terms of NDVI values. Climate change leads to a spatial relocation of tree communities, treelines and ecozones, thus an interpretation of future tree vitality and biomass trends directly from the recent relationships between NDVI and climate parameters is difficult. While climate plays a major role for vegetation and treeline distribution in Mongolia, the disappearing permafrost needs to be accounted for as a limiting factor for tree growth when modeling future trends of climate warming and human forest disturbance."],["dc.format.extent","25"],["dc.identifier.doi","10.5194/bg-2017-220"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/65133"],["dc.language.iso","en"],["dc.title","Climate effects onthe vitality of boreal forestsat the treeline in different ecozonesof Mongolia"],["dc.type","preprint"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]