Sökresultat

Filtyp

Din sökning på "Buy fc 26 coins Buyfc26coins.com is EA Sports official for FC 26 coins Perfect service thanks a lot guys..VFmk" gav 50849 sökträffar

Growth of saprotrophic fungi and bacteria in soil.

Bacterial and fungal growth rate measurements are sensitive variables to detect changes in environmental conditions. However, while methods to assess the species composition and biomass of fungi and bacteria has made much progress, information about growth rates remains surprisingly rudimentary. We review the recent history of approaches to assess bacterial and fungal growth rates, leading up to c

Bird population trends are linearly affected by climate change along species thermal ranges

Beyond the effects of temperature increase on local population trends and on species distribution shifts, how populations of a given species are affected by climate change along a species range is still unclear. We tested whether and how species responses to climate change are related to the populations locations within the species thermal range. We compared the average 20 year growth rates of 62

Land use intensity and landscape complexity-Analysis of landscape characteristics in an agricultural region in Southern Sweden

It is generally recognised that agricultural intensification has lead to simplification of landscape structure, but it has not been clarified if this is a ubiquitous relationship. That is, it has been an open question whether agricultural intensity and landscape simplicity should be regarded as one single or as two separate dimensions. To evaluate this we analysed landscape data in 136 different 1

The Full Annual Carbon Balance of Boreal Forests Is Highly Sensitive to Precipitation

The boreal forest carbon balance is predicted to be particularly sensitive to climate change. Carbon balance estimates of these biomes stem mainly from eddy-covariance measurements of net ecosystem exchange (NEE). However, a full net ecosystem carbon balance (NECB) must include the lateral carbon export (LCE) through discharge. We show that annual LCE at a boreal forest site ranged from 4 to 28%,

Future climate impact on spruce bark beetle life cycle in relation to uncertainties in regional climate model data ensembles

In this study, we quantify the effect of uncertainties in climate projections on an impact model (IPS) that describes the temperature-dependent swarming and development of Ips typographus. Three forcing climate data sets (ensembles) were used: (1) E-Obs gridded observations, (2) ERA-40 reanalysis data downscaled by eight regional climate models (RCMs) and (3) regional scenarios from one RCM forced

The structuring of quantitative genetic variation in a fragmented population of Briza media (Poaceae)

The structuring of quantitative genetic variation can have a significant impact on the adaptive potential and long-term viability of species in changing landscapes. The present study of the grass Briza media investigated the relationships between patterns of heritable variation in phenotypic characters and descriptors of landscape structure, land-use history and local habitat conditions in a lands

The grey partridge and AESs in Sweden: Setting up an experimental restoration of the grey partridge and associated farmland biodiversity in Sweden

The grey partridge Perdix perdix has suffered a severe decline in numbers and contraction in range during the last half century. The loss of landscape heterogeneity through agricultural intensification has often been indicated as a cause. By preserving and managing small biotopes and creating uncropped border zones, some ecological heterogeneity is maintained and recreated with the aid of agri-env

The status of the Nordic populations of the Mallard (Anas platyrhynchos) in a changing world

Dabbling ducks (Anas spp.) are important migratory quarry species, protected as a shared resource under international legislation. However, there is a lack of sufficient high-quality data on vital demographic rates and long-term trends in numbers to judge the conservation status of many duck populations at the flyway level. In response to reported declines in the North-West European flyway populat

The production and turnover of extramatrical mycelium of ectomycorrhizal fungi in forest soils: role in carbon cycling

There is growing evidence of the importance of extramatrical mycelium (EMM) of mycorrhizal fungi in carbon (C) cycling in ecosystems. However, our understanding has until recently been mainly based on laboratory experiments, and knowledge of such basic parameters as variations in mycelial production, standing biomass and turnover as well as the regulatory mechanisms behind such variations in fores

Evaluation of methods to estimate production, biomass and turnover of ectomycorrhizal mycelium in forests soils - A review

Mycorrhizal fungi constitute a considerable sink for carbon in most ecosystems. This carbon is used for building extensive mycelial networks in the soil as well as for metabolic activity related to nutrient uptake. A number of methods have been developed recently to quantify production, standing biomass and turnover of extramatrical mycorrhizal mycelia (EMM) in the field. These methods include min

Bacterial growth and respiration responses upon rewetting dry forest soils: Impact of drought-legacy

Longer periods of drought and droughts of higher intensity are expected to become increasingly frequent with future climate change. This has implications for the microbially mediated turnover of soil organic matter (SOM), which will feedback to the global C cycle. In this study, we addressed the microbial dynamics underlying the pulse of respiration following rewetting of dry soil, and how the dro

Up-scaling of water use efficiency from leaf to canopy as based on leaf gas exchange relationships and the modeled in-canopy light distribution

Abstract in UndeterminedThe aim of this study was to evaluate the extent to which water use efficiency (WUE) at leaf scale can be used to assess WUE at canopy scale, leaf WUE being assumed to be a constant function of vapor pressure deficit and to thus not be dependent upon other environmental factors or varying leaf properties. Leaf WUE and its variability and dependencies were assessed using lea

Revisiting the hypothesis that fungal-to-bacterial dominance characterizes turnover of soil organic matter and nutrients

Resolving fungal and bacterial groups within the microbial decomposer community is thought to capture disparate life strategies for soil microbial decomposers, associating bacteria with an r-selected strategy for carbon (C) and nutrient use, and fungi with a K-selected strategy. Additionally, food-web model-based work has established a widely held belief that the bacterial decomposer pathway in so

Growth and carbon sequestration by ectomycorrhizal fungi in intensively fertilized Norway spruce forests

A substantial portion of the carbon (C) fixed by the trees is allocated belowground to ectomycorrhizal (EM) symbionts, but this fraction usually declines after fertilization. The aim of the present study was to estimate the effect of optimal fertilization (including all the necessary nutrients) on the growth of EM fungi in young Norway spruce forests over a three year period. In addition, the amou

Use and misuse of PLFA measurements in soils

The determination of the phospholipid fatty acid (PLFA) pattern of soil organisms has become one of the most commonly used methods to study microbial community structure. Here we recapitulate the background of our work applying the PLFA method to soil in the early 1990s. We also stress that although the PLFA method was, and still is, a rapid and sensitive method to detect changes in the microbial

Biochar-mediated changes in soil quality and plant growth in a three year field trial

While many laboratory studies have focused on the short term effects of biochar addition to soil), there have been comparatively few tracing its longer term effects in the field. This study investigated the multiyear impact of biochar on crop performance and soil quality with specific emphasis on carbon (C) and nitrogen (N) cycling over a 3 y period. Biochar was added to an agricultural field at 0

Budburst model performance: The effect of the spatial resolution of temperature data sets

Phenological models have mainly been developed to capture the seasonal development of individual trees and local populations, using data from meteorological stations. Ecosystem models that incorporate phenology are however commonly driven by gridded climate data. Using two phenological models to simulate budburst of birch in Germany, we assessed how combining phenological point observations with g

Is population structure in the European white stork determined by flyway permeability rather than translocation history?

European white stork are long considered to diverge to eastern and western migration pools as a result of independent overwintering flyways. In relatively recent times, the western and northern distribution has been subject to dramatic population declines and country-specific extirpations. A number of independent reintroduction programs were started in the mid 1950s to bring storks back to histori

Symbiotic adaptations in the fungal cultivar of leaf-cutting ants.

Centuries of artificial selection have dramatically improved the yield of human agriculture; however, strong directional selection also occurs in natural symbiotic interactions. Fungus-growing attine ants cultivate basidiomycete fungi for food. One cultivar lineage has evolved inflated hyphal tips (gongylidia) that grow in bundles called staphylae, to specifically feed the ants. Here we show exten

A Puzzling Migratory Detour: Are Fueling Conditions In Alaska Driving The Movement Of Juvenile Sharp-Tailed Sandpipers?

Making a detour can be advantageous to a migrating bird if fuel-deposition rates at stopover sites along the detour are considerably higher than at stopover sites along a more direct route. One example of an extensive migratory detour is that of the Sharp-tailed Sandpiper (Calidris acuminata), of which large numbers of juveniles are found during fall migration in western Alaska. These birds take a