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Wild Pollinators Enhance Fruit Set of Crops Regardless of Honey Bee Abundance

The diversity and abundance of wild insect pollinators have declined in many agricultural landscapes. Whether such declines reduce crop yields, or are mitigated by managed pollinators such as honey bees, is unclear. We found universally positive associations of fruit set with flower visitation by wild insects in 41 crop systems worldwide. In contrast, fruit set increased significantly with flower

Millennial Climatic Fluctuations Are Key to the Structure of Last Glacial Ecosystems

Whereas fossil evidence indicates extensive treeless vegetation and diverse grazing megafauna in Europe and northern Asia during the last glacial, experiments combining vegetation models and climate models have to-date simulated widespread persistence of trees. Resolving this conflict is key to understanding both last glacial ecosystems and extinction of most of the mega-herbivores. Using a dynami

Mineralization of low molecular weight carbon substrates in soil solution under laboratory and field conditions

A more detailed mechanistic understanding of how low molecular weight (MW) carbon (C) substrates are mineralized within the rhizosphere by soil microbial communities is crucial to accurately model terrestrial C fluxes. Currently, most experiments regarding soil C dynamics are conducted ex-situ (laboratory) and can fail to account for key variables (e.g. temperature and soil water content) which va

Joint Production of Food and Wildlife: Uniform Measures or Nature Oases?

Intensive agriculture is often bad for wildlife. Does this imply that a goal to boost wildlife on agricultural land is best met through a general reduction in intensity? We argue that such an approach may not be optimal, since cost functions for provision of wildlife on agricultural land may be non-convex, due to fixed costs associated with such provision. This implies that, even when farms are id

Masting behaviour and dendrochronology of European beech (Fagus sylvatica L.) in southern Sweden

To identify weather controls of beech diameter growth and masting in southern Sweden, we analyze records of monthly weather, regional masting record, and tree-ring chronologies from five beech-dominated stands. The results indicate a strong weather control of temporal pattern of masting events in southern Sweden over the second half of the 20th century. Negative summer temperature anomaly 2 years

Species and gene divergence in Littorina snails detected by array comparative genomic hybridization

Background: Array comparative genomic hybridization (aCGH) is commonly used to screen different types of genetic variation in humans and model species. Here, we performed aCGH using an oligonucleotide gene-expression array for a non-model species, the intertidal snail Littorina saxatilis. First, we tested what types of genetic variation can be detected by this method using direct re-sequencing and

Refugee species: which historic baseline should inform conservation planning?

Understanding species’ historical ranges can provide important information for conservation planning in the face of environmental change. Cromsigt et al. (this issue) comment on our recent European bison (Bison bonasus) range reconstruction, suggesting that bison were already 8000 years ago a refugee species (i.e. restricted to marginal habitat due to past human pressure) and that species distribu

Archaeal abundance in relation to root and fungal exudation rates

Archaea are ubiquitous in forest soils, but little is known about the factors regulating their abundance and distribution. Low molecular weight organic compounds represent an important energy source for archaea in marine environments, and it is reasonable to suspect that archaeal abundance is dependent on such compounds in soils as well, represented by, for example, plant and fungal exudates. To t

Soil carbon sequestration and climate change in semi-arid Sudan

Climate change poses risk for natural and human systems in Africa. Increasing temperatures and changes in precipitation patterns is likely to affect agriculture, pastoralism and forestry. Mitigation of increasing atmospheric concentration of CO2 through soil carbon sequestration in semi-arid ecosystems may be beneficial to soil properties and cultivation. This paper describes and discusses soil ca

Low cross-taxon congruence and weak stand-age effects on biodiversity in Swedish oak forests

Assessing cross-taxon congruence is vital for effective forest conservation, because different taxonomic groups may respond inconsistently to key habitat variables such as stand age. We examined six taxonomic groups—insects, arachnids, springtails, epiphytic lichens, bryophytes, and vascular plants—across 25 Swedish oak stands ranging from 19 to 165 years old to determine whether species richness

Where to restore : Connectivity forest for spatial prioritization in forest landscape restoration

Forest loss, fragmentation, and transformation negatively impact forest biodiversity and ecosystem functionality worldwide. Improving landscape intactness and connectivity through restoration is critical. Determining where to restore remains, however, a challenge. As an approach for prioritizing restoration areas, we define connectivity forest (CFs) as forests outside recognized high conservation

Structural variation in the pangenome of wild and domesticated barley

Pangenomes are collections of annotated genome sequences of multiple individuals of a species1. The structural variants uncovered by these datasets are a major asset to genetic analysis in crop plants2. Here we report a pangenome of barley comprising long-read sequence assemblies of 76 wild and domesticated genomes and short-read sequence data of 1,315 genotypes. An expanded catalogue of sequence

Opposing effects of nitrogen versus phosphorus additions on mycorrhizal fungal abundance along an elevational gradient in tropical montane forests

Studies in temperate systems provide evidence that the abundance of arbuscular mycorrhizal fungal (AMF) depends on soil nutrient availability, which is mainly explained in the context of resource stoichiometry and differential plant biomass allocation. We applied this concept to an understudied ecosystem - tropical montane forest - analyzing root and AMF abundance along an elevational gradient wit

Slash-and-burn practices decrease arbuscular mycorrhizal fungi abundance in soil and the roots of Didierea madagascariensis in the dry tropical forest of madagascar

Deforestation and the use of fire to clear land have drastic effects on ecosystem functioning and compromise essential ecosystem services, especially in low-income tropical countries such as Madagascar. We evaluated the effects of local slash-and-burn practices on soil nutrients and arbuscular mycorrhizal (AM) fungi abundance in a southwestern Madagascar forest. Nine sampling plot pairs were estab

CEASA : Dominant spatial autocorrelation in dual-constraint calibration as the game-changer for hydrological modeling with high-uncertainty remotely sensed evaporation: Application to the Meichuan basin

Accurate evapotranspiration (ET) estimation is vital for hydrological modeling, yet remotely sensed ET (RS-ET) products are often limited by algorithmic uncertainties and sensor biases. To mitigate error propagation and better capture spatial patterns, this study introduces the Composite Efficiency of Absolute ET and Spatial Autocorrelation (CEASA) —a dual-constraint framework that integrates abso