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The timing of diel stem growth of mature forest trees is still largely unknown, as empirical data with high temporal resolution have not been available so far. Consequently, the effects of day-night conditions on tree growth remained uncertain. Here we present the first comprehensive field study of hourly-resolved radial stem growth of seven temperate tree species, based on 57 million underlying data points over a period of up to 8 years. We show that trees grow mainly at night, with a peak after midnight, when the vapour pressure deficit (VPD) is among the lowest. A high VPD strictly limits radial stem growth and allows little growth during daylight hours, except in the early morning. Surprisingly, trees also grow in moderately dry soil when the VPD is low. Species-specific differences in diel growth dynamics show that species able to grow earlier during the night are associated with the highest number of hours with growth per year and the largest annual growth increment. We conclude that species with the ability to overcome daily water deficits faster have greater growth potential. Furthermore, we conclude that growth is more sensitive than carbon uptake to dry air, as growth stops before stomata are known to close.

The timing of diel stem growth of mature forest trees is still largely unknown, as empirical data with high temporal resolution have not been available so far. Consequently, the effects of day-night conditions on tree growth remained uncertain. Here we present the first comprehensive field study of hourly-resolved radial stem growth of seven temperate tree species, based on 57 million underlying data points over a period of up to 8 years. We show that trees grow mainly at night, with a peak after midnight, when the vapour pressure deficit (VPD) is among the lowest. A high VPD strictly limits radial stem growth and allows little growth during daylight hours, except in the early morning. Surprisingly, trees also grow in moderately dry soil when the VPD is low. Species-specific differences in diel growth dynamics show that species able to grow earlier during the night are associated with the highest number of hours with growth per year and the largest annual growth increment. We conclude that species with the ability to overcome daily water deficits faster have greater growth potential. Furthermore, we conclude that growth is more sensitive than carbon uptake to dry air, as growth stops before stomata are known to close.

Aggregated moss layer projective vegetation cover is given in percent for each taxon for 57 sites. The cover of different vegetation types at the sites is given in percent as well.The vegetation surveys were carried out in four different study areas in the Sakha Republic, Russia: in the mountainous region of the Verkhoyansk Range within the Oymyakonsky and Tomponsky District (Event EN21-201 - EN21-219), and in three lowland regions of Central Yakutia within the Churapchinsky, Tattinsky and the Megino-Kangalassky District (Event EN21220 - EN21264). The study area is located within the boreal forest biome that is underlain by permafrost soils. The aim was to record the projective ground vegetation in different boreal forest types studied during the RU-Land_2021_Yakutia summer field campaign in August and September 2021.The ground vegetation projective cover in percent was assessed within a circular forest plot of 15m radius. Depending on the heterogeneity of the forest plot, multiple vegetation types (VA, VB, or VC) were surveyed separately. The assignment of a vegetation type is always unique to a site. Up to four quadrats of 2x2 m were surveyed per vegetation type and projective cover in percent recorded separately for herbaceous and moss layers. All vegetation smaller than 40 cm was recorded. Additionally, ground vegetation projective cover was surveyed in 4 rings of 50 cm width around the center of the circular forest plot. Photos of quadrats were taken at the time of survey.Average ground vegetation cover per plot was calculated by using an average weighted by vegetation types for each site. The ring survey data was not included in the plot average.In total, 491 quadrats at 57 forest plots were investigated. All data were collected by scientists form the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) Germany, the University of Potsdam Germany, and the North-Easter Federal University of Yakutsk (NEFU) Russia.

Updated knowledge about the glacier extent and characteristics in the Himalaya cannot be overemphasised. Availability of precise glacier inventories in the latitudinally diverse western Himalayan region is particularly crucial. In this study we have created an inventory of the Suru sub-basin, western Himalaya for year 2017 using Landsat OLI data. Changes in glacier parameters have also been monitored from 1971 to 2017 using temporal satellite remote sensing data and limited field observations. Inventory data shows that the sub-basin has 252 glaciers covering 11% of the basin, having an average slope of 25 ±6° and dominantly north orientation. The average snow line altitude (SLA) of the basin is 5011 ±54 masl with smaller (47%) and cleaner (43%) glaciers occupying the bulk area. Longterm climate data (1901-2017) shows an increase in the mean annual temperature (Tmin & Tmax) by 0.77 ºC (0.25 & 1.3 ºC) in the sub-basin, driving the overall glacier variability in the region. Temporal analysis reveals a glacier shrinkage of ~6 ±0.02 %, an average rate of 4.3 ±1.02 ma-1, debris increase of 62% and 22 ±60 m SLA rise in past 46 years. This confirms their transitional response between the Karakoram and the Greater Himalayan Range (GHR) glaciers. Besides, glaciers in the sub-basin occupy two major ranges, i.e., GHR and Ladakh range (LR) and experience local climate variability, with the GHR glaciers exhibiting a warmer and wetter climate as compared to the LR glaciers. This variability manifestes itself in the varied response of GHR and LR glaciers. While the GHR glaciers exhibit an overall rise in SLA (GHR: 49 ±69 m; LR: decrease by 18 ±50 m), the LR glaciers have deglaciated more (LR: 7 %; GHR: 6 %) with an enhanced accumulation of debris cover (LR: 73%; GHR: 59 %). Inferences from this study reveal prevalence of glacier disintegration and overall degeneration, transition of clean ice to partially debris covered glaciers, local climate variability and non-climatic (topographic and morphometric) factor induced heterogeinty in glacier response as the major processes operatives in this region.

The data set features the variance of aboveground plant biomass along a 600km long gradient in Mongolian rangeland vegetation. The data was collected to study the role of climatic variability for the effects of grazing in rangelands. 15 sites were selected across a 600 km long precipitation gradient in Central Mongolia. At each site, 5 subplots were sampled within each distance of 50m, 150m, 350, 750m and 1500m to a grazing hotspot. The 375 plots were visited in 2014 and resampled in 2015. The samples were clipped at ground level on 50 cm x 50 cm plots, separated into plant functional groups, dried at 65°C for 24h and weighted. More information is available in the corresponding paper.

The timing of diel stem growth of mature forest trees is still largely unknown, as empirical data with high temporal resolution have not been available so far. Consequently, the effects of day-night conditions on tree growth remained uncertain. Here we present the first comprehensive field study of hourly-resolved radial stem growth of seven temperate tree species, based on 57 million underlying data points over a period of up to 8 years. We show that trees grow mainly at night, with a peak after midnight, when the vapour pressure deficit (VPD) is among the lowest. A high VPD strictly limits radial stem growth and allows little growth during daylight hours, except in the early morning. Surprisingly, trees also grow in moderately dry soil when the VPD is low. Species-specific differences in diel growth dynamics show that species able to grow earlier during the night are associated with the highest number of hours with growth per year and the largest annual growth increment. We conclude that species with the ability to overcome daily water deficits faster have greater growth potential. Furthermore, we conclude that growth is more sensitive than carbon uptake to dry air, as growth stops before stomata are known to close.

Background: Urbanization is an important indicator of economic growth and social change but is associated with environmental degradation, which threatens sustainable growth of African cities. One of the most vulnerable ecosystems in urban areas are wetlands. In Uganda, wetlands cover an area of 11% of the country's land area. Half of the wetland areas in Ugandan cities have been converted to industry and residential areas, and urban agriculture. There is limited information on the extent of wetland conversion or utilization for urban agriculture. The objective of this study was to investigate the extent of wetlands lost in two Ugandan cities, Wakiso and Kampala, in the last 30 years. Secondly, we demonstrate a simple methodology to monitor agriculture on encroached wetlands.Methods: Using a field survey and free remote sensing data from Landsat TM 1986 and Landsat ETM 2016 we classified the rate of wetland loss and encroachment in the last 30 years. Using MODIS NDVI 16-day composites at 500-meter spatial resolution, we generated distinctive crops and crop mixtures in the encroached wetlands for urban agriculture using the ISODATA clustering algorithm.Results: Over a 30-year period, 72,828 ha (73%) of the Wakiso-Kampala wetlands have been lost. Agriculture area on the other hand doubled. Of the new cultivation area, 16,488 ha (23%) were reclaimed from wetlands. All cultivated agriculture in Kampala was in the wetlands while in Wakiso, 73% of crop agriculture was in the wetlands. The major crops grown in these urban wetlands were banana (20%), sugarcane (22%), maize (17%), Eucalyptus trees (12%), sweet potatoes (10%), while ornamental nurseries, pine trees, vegetables and passion fruits were each at 5%.Conclusions: The Kampala-Wakiso wetlands have been disappearing at a rate of 2500 ha annually for the last 30 years, implying that at this rate, there will be no wetlands left by 2029. Policy implications are that, ecosystem services by of urban wetlands have been lost, a large population of urban poor are using wetlands for survival and yet Poverty eradication policies are in conflict with wetland conservation policies. Policy recommendations we endorse are,the Government of Uganda needs to promote wetland reclamation programs so as to restore and reconstruct lost and fragmented wetlands. Secondly, ministries mandated to food security and poverty eradication need to convene with ministries regulating wetlands to merge these conflicting policies. Thirdly, there is need for the development of polices that are inclusive of challenges faced by the urban poor while at the same time minimize the pressures on urban environments.

Time series of climate variables (description see HD_variable description.xlsx) at the TERENO flux tower /climate station close to Hordorf (DE-Hod, Latitude/Longitude 52.00128, 11.17769, elevation 80 m) of the entire year 2020, resolution 10 min, quality assured. All variables contain flags in a separate column named 'variable_f', in case this flag column contains '-9999', no quality control is performed at this stage, otherwise the flags are strings initiated by a '9' and then followed by numbers either '0', '1' or '2' on different positions of the string. The positions indicate either the automated test performed or a flag set manually due to maintenance activities (0=good, 1=suspect, 2=bad). The field was cultivated with sugar beet during the vegetation period of 2020.The time base is CET.