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Drought is predicted to increase in the future due to climate change, bringing with it myriad impacts on ecosystems. Plants respond to drier soils by reducing stomatal conductance in order to conserve water and avoid hydraulic damage. Despite the importance of plant drought responses for the global carbon cycle and local and regional climate feedbacks, land surface models are unable to capture obs

In 2018, up to 4 million m3 Norway spruce was killed by the spruce bark beetle Ips typographus in Sweden. The event was unique for Sweden, in terms of both affected volume and the fact that it was triggered by severe drought stress, not by ample availability of relatively defenseless storm-felled trees. The outbreak continued in 2019 and 2020, each year with twice as many trees killed as in 2018.

Compared to the well-known drivers of spatial variability in gross primary productivity (GPP), the relative importance of climatic variables, soil properties and plant traits to the spatial variability in net ecosystem exchange of CO2 between terrestrial ecosystem and atmosphere (NEE) is poorly understood. We used principal component regression to analyze data from 147 eddy flux sites to disentang

West African Sahelian and Sudanian ecosystems provide essential services to people and also play a significant role within the global carbon cycle. However, climate and land use are dynamically changing, and uncertainty remains with respect to how these changes will affect the potential of these regions to provide food and fodder resources or how they will affect the biosphere-atmosphere exchange

Leaf mass per area (LMA) is a key plant functional trait closely related to leaf biomass. Estimating LMA in fresh leaves remains challenging due to its masked absorption by leaf water in the short-wave infrared region of reflectance. Vegetation indices (VIs) are popular variables used to estimate LMA. However, their physical foundations are not clear and the generalization ability is limited by th

The eddy-covariance (EC) method is the most direct micrometeorological approach to measure the surface–atmosphere trace gases under turbulent conditions. The measurement of trace gas fluxes by eddy covariance requires fast-response instruments (higher than 1 Hz) to measure the turbulent fluctuations of vertical wind velocity and trace gas mixing ratio. For many trace gas species, such fast respons

Sisal (Agave sisalana) is a climate-resilient crop grown on large-scale farms in semi-arid areas. However, no studies have investigated soil greenhouse gas (GHGs: CO2, N2O and CH4) fluxes from these plantations and how they relate to other land cover types. We examined GHG fluxes (Fs) in a sisal chronosequence at Teita Sisal Estatein southern Kenya. The effects of stand age on Fs were examined usi

Incomplete wildfire combustion in boreal forests leaves behind legacy plant-soil feedbacks known to restrict plant biodiversity. These restrictions can inhibit carbon recapture after fire by limiting ecosystem transition to vegetation growth patterns that are capable of offsetting warmth-enhanced soil decomposition under climate change. Here, we field-surveyed plant regrowth conditions 2 years aft

Lake–atmosphere carbon exchanges can be significantly affected by photochemical dissolved organic matter (DOM) mineralization. However, our understanding of how increasing allochthonous organic carbon input affects the photoreactivity of DOM per unit of absorbed incoming light is incomplete. Here, we measured the absorption of ultraviolet (UV) light and subsequent photochemical DOM decay in 148 la

Field studies reveal that the woody surfaces of upland trees are a substantial global sink for methane, a potent greenhouse gas. The findings help to fill a hole in the global methane budget and should improve the accuracy of climate models.

Changes in the net carbon sink of boreal forests constitute a major source of uncertainty in the future global carbon budget and, hence, climate change projections. The annual net ecosystem exchange of carbon dioxide (CO2) controlling the terrestrial carbon stock results from the small difference between respiratory CO2 release and the photosynthetic CO2 uptake by vegetation. The boreal forest, an

The complex topography in mountainous regions, exemplified by factors like slope aspect, leads to noticeable variations in vegetation patterns, which are fundamental for understanding mountain ecosystems. However, a consistent global-scale quantification of topography's influence on vegetation patterns is still lacking. Here, we utilize two phenological metrics as proxies for vegetation-maximum ve

Residents of the Sahel depend on livestock, but harsh environmental conditions during the dry season limit rangeland forage, which is the main source of livestock feed. Al-though operational tools exist for assessing and monitoring forage quantity during the dry season, assessments of forage quality are lacking. We addressed this gap by developing satellite-based monitoring of forage quality acros

Current analyses and predictions of spatially explicit patterns and processes in ecology most often rely on climate data interpolated from standardized weather stations. This interpolated climate data represents long-term average thermal conditions at coarse spatial resolutions only. Hence, many climate-forcing factors that operate at fine spatiotemporal resolutions are overlooked. This is particu

Fog makes a significant contribution to the hydrology of a wide range of important terrestrial ecosystems. The amount and frequency of fog immersion are affected by rapid ongoing anthropogenic changes but the impacts of these changes remain relatively poorly understood compared with changes in rainfall. Here, we present the design and performance of a novel experiment to actively manipulate low ly

Background: In the Sahel, one of the largest semi-arid areas in the world, pastoral livestock is the main source of protein for the local population. The quantification of herbaceous biomass in the Sahelian rangelands is of major importance since it provides food for the livestock. The main method used to monitor the biomass consists of cutting, drying, and weighting it. However, indirect methods

Drought is a multifaceted phenomenon driven by both natural climate fluctuations and human activities. Unlike traditional, slow-developing droughts, flash droughts (FDs) emerge suddenly and intensify rapidly, posing significant challenges for natural resource management. The lack of effective tools to quantify FDs exacerbates stakeholders' concerns, particularly due to the risks they pose to water