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Cutover Peat Limits Methane Production Causing Low Emission at a Restored Peatland

Peatland degradation due to human activities is contributing to rising atmospheric CO2 levels. Restoring the carbon (C) sink function in degraded peatlands and preventing further stored C losses is a key climate mitigation strategy, given the global scale of peatland disturbance. Active restoration involving a combination of rewetting and vegetation reestablishment at a post-extraction peatland in

Mesoamerica is a cradle and the Atlantic Forest is a museum of Neotropical butterfly diversity : Insights from the evolution and biogeography of Brassolini (Lepidoptera: Nymphalidae)

Regional species diversity is explained ultimately by speciation, extinction and dispersal. Here, we estimate dispersal and speciation rates of Neotropicaal butterflies to propose an explanation for the distribution and diversity of extant species. We focused on the tribe Brassolini (owl butterflies and allies), a Neotropical group that comprises 17 genera and 108 species, most of them endemic to

What is the effect of giving the grazers access to additional nutrient sources on biodiversity in semi-natural pastures? A systematic review protocol

Background: Semi-natural pastures are unfertilized grasslands with a long history of traditional low-input grazing management. This kind of pastures are recognized for their high species richness. However, as a consequence of modernization of agriculture, many of the semi-natural pastures have been lost during the last century, leading to a serious threat to farmland biodiversity. Semi-natural pas

Hot topics in agricultural and environmental economics – a large-scale bibliometric analysis

Land use is at the core of today’s complex sustainability challenges. Agricultural and environmental economics share a focus land and resource use but evolved in their own domains. Their specialized competencies can be complementary and thus strengthen policy analysis. We use structural topic modelling on more than 24,000 articles in the top agricultural economics and environmental economics journ

The Impacts of Climate and Wildfire on Ecosystem Gross Primary Productivity in Alaska

The increase in wildfire occurrence and severity seen over the past decades in the boreal and Arctic biomes is expected to continue in the future in response to rapid climate change in this region. Recent studies documented positive trends in gross primary productivity (GPP) for Arctic boreal biomes driven by warming, but it is unclear how GPP trends are affected by wildfires. Here, we used satell

Effects of livestock and wildlife grazing intensity on soil carbon dioxide flux in the savanna grassland of Kenya

Although grazing is the primary land use in the savanna lowland of southern Kenya, the effects of grazing on soil carbon dioxide flux (RS) remain unclear. A 12-month study was conducted from January to December 2020 on the effects of six grazing intensities sites (overgrazed (OG), heavily grazed (HG), moderately grazed (MG), moderately to lightly grazed (M-LG), lightly grazed (LG) and no grazing (

Leaf-scale study of biogenic volatile organic compound emissions from willow (Salix spp.) short rotation coppices covering two growing seasons

In Europe, willow (Salix spp.) trees have been used commercially since the 1980s at a large scale to produce renewable energy. While reducing fossil fuel needs, growing short rotation coppices (SRCs), such as poplar or willow, may have a high impact on local air quality as these species are known to produce high amounts of isoprene, which can lead to the production of tropospheric ozone (O3). Here

Broad-Scale Patterns in CDOM and Total Organic Matter Concentrations of Inland Waters – Insights from Remote Sensing and GIS

The rise in CDOM (coloured dissloved organic matter) is likely to be relatively more pronounced in remote northern regions. However, there is a lack of monitoring to confirm this. For this reason, there is a strong incentive to develop remote sensing-based methods to map CDOM in lakes across broader geographical scales and to include geograghic contex in such analysis. There is a lack of understan

Understanding the environmental regulation of tree phenology

In temperate and boreal climates, trees synchronise their annual growth cycles with seasonal changes in daylength and temperature. Understanding how environmental cues regulate tree phenology is important to our ability to capture the potential responses of trees to climate change, with implications for forest productivity.In this thesis, we demonstrated that different research methods can be appl

HIMMELI v1.0 : HelsinkI Model of MEthane buiLd-up and emIssion for peatlands

Wetlands are one of the most significant natural sources of methane (CH4) to the atmosphere. They emit CH4 because decomposition of soil organic matter in waterlogged anoxic conditions produces CH4, in addition to carbon dioxide (CO2). Production of CH4 and how much of it escapes to the atmosphere depend on a multitude of environmental drivers. Models simulating the processes leading to CH4 emissi

Disaggregation of SMOS soil moisture over West Africa using the Temperature and Vegetation Dryness Index based on SEVIRI land surface parameters

The overarching objective of this study was to produce a disaggregated SMOS Soil Moisture (SM) product using land surface parameters from a geostationary satellite in a region covering a diverse range of ecosystem types. SEVIRI data at 15 min temporal resolution were used to derive the Temperature and Vegetation Dryness Index (TVDI) that served as SM proxy within the disaggregation process. West A

Shock and stabilisation following long-term drought in tropical forest from 15 years of litterfall dynamics

Litterfall dynamics in tropical forests are a good indicator of overall tropical forest function, indicative of carbon invested in both photosynthesising tissues and reproductive organs such as flowers and fruits. These dynamics are sensitive to changes in climate, such as drought, but little is known about the long-term responses of tropical forest litterfall dynamics to extended drought stress.

Crop loss evaluation using digital surface models from unmanned aerial vehicles data

Precision agriculture and Unmanned Aerial Vehicles (UAV) are revolutionizing agriculture management methods. Remote sensing data, image analysis and Digital Surface Models derived from Structure from Motion and Multi-View Stereopsis offer new and fast methods to detect the needs of crops, greatly improving crops efficiency. In this study, we present a tool to detect and estimate crop damage after

Variability of BVOC Emissions from Commercially Used Willow (Salix spp.) Varieties

Willow (Salix spp.) trees are commonly used in short rotation coppices (SRC) to produce renewable energy. However, these plants are also known to emit high concentrations of biogenic volatile organic compounds (BVOCs), which have a large influence on air quality. Many different clones of commercially used Salix varieties exist today, but only a few studies have focused on BVOC emissions from these

Asymmetric patterns and temporal changes in phenology-based seasonal gross carbon uptake of global terrestrial ecosystems

Aim: To study global patterns and temporal changes in the seasonal dynamics (quantity and seasonal distribution) of terrestrial gross carbon uptake in response to global environmental change. Location: Global. Time period: 2000–2016. Major taxa studied: Terrestrial ecosystems. Methods: Following a phenology-based definition of photosynthetic seasonality, we decompose gross primary production (GPP)

Testing the dependence of microbial growth and carbon use efficiency on nitrogen availability, pH, and organic matter quality

Microbial carbon use efficiency (CUE), or the partitioning of assimilated C into growth or respiration, is a key parameter that is central to understanding the soil C cycle and its feedback to environmental and climate change. The availability of nitrogen (N), organic matter (OM) quality and environmental factors influence CUE indirectly by affecting growth rates and respiration of the major micro

Modelling Populus autumn phenology : The importance of temperature and photoperiod

In late summer-early autumn, trees undergo growth cessation culminating in bud set. For a wide range of plants, including Populus, photoperiod is considered as the primary environmental cue determining timing of growth cessation and shoot to bud transition. However, studies on Populus have revealed temperature influence on seasonal growth cessation and bud set. In this study we examine the role of