Effect of Habitat Size,Quality, and Isolation on Functional Groups of Beetles in Hollow Oaks

One of the largest threats to biodiversity is land use change and habitat loss. Hollow oaks (Quercus spp. L.) are well-defined patches that are hotspots for biodiversity and red-listed species, but they are often rare and fragmented in the landscape. We investigated the effect of patch size, habitat quality, and isolation on functional groups and red-listed saproxylic beetles in hollow oaks (n = 40) in Norway. The groups were defined by host tree association, trophic grouping, and red-listed status. Habitat quality, represented by tree form was most important in explaining species richness for most groups. Patch size, represented by circumference and amount of dead branches, was most important in explaining abundance. Isolation, that is single oaks compared with oaks in groups, had a negative effect on the abundance of beetles feeding both on wood and fungi (xylomycethopagous), as well as on species associated with broadleaved trees (oak semi-specialists), but did not affect species richness. This indicates that at this scale and in this landscape, isolated oaks are as species rich and valuable for conservation as other oaks, although some functional groups may be more vulnerable to isolation than others. The red-listed species only responded to patch size, indicating that oaks with large circumference and many dead branches are especially important for red-listed species and for conservation.     

Post-mortem changes in porcine M. longissimus studied by solid-state 13C cross-polarization magic-angle spinning nuclear magnetic resonance spectroscopy

Solid-state (13)C cross-polarization (CP) magic-angle spinning (MAS) nuclear magnetic resonance (NMR) experiments are carried out for the first time on rapidly frozen muscle biopsies taken in M. longissimus in vivo and at 1 min, 45 min, and 24 h post-mortem from three pigs. Two of the pigs were CO(2)-stunned (control animals), and one was pre-slaughter-stressed (treadmill exercise) followed by electrical stunning to induce difference in metabolism post-mortem. (13)C resonance signals from saturated and unsaturated carbons in fatty acids, carboxylic carbons, and carbons in lactate and glycogen are identified in the solid-state NMR spectra. The (13)C CP MAS spectra obtained for post-mortem samples of the stressed, electrically stunned pig differ significantly from the post-mortem control samples, as the intensity of a resonance line appearing at 30 ppm, assigned to carbons of the methylene chains, is reduced for the stressed pig. This spectral difference is probably due to changes in lipid mobility and indicates altered membrane properties in the muscle of the stressed/electrically stunned animal when compared with the control animals already 1 min post-mortem. In addition, the post-mortem period changes in glycogen carbons can be estimated from the (13)C CP MAS spectra, yielding a correlation of r = 0.74 to subsequent biochemical determination of the glycogen content.     

Grain yield increase in cereal variety mixtures: A meta-analysis of field trials

Plant ecology theory predicts that growing seed mixtures of varieties (variety mixtures) may increase grain yields compared to the average of component varieties in pure stands. Published results from field trials of cereal variety mixtures demonstrate, however, both positive and negative effects on grain yield. To investigate the prevalence and preconditions for positive mixing effects, reported grain yields of variety mixtures and pure variety stands were obtained from previously published variety trials, converted into relative mixing effects and combined using meta-analysis. Furthermore, available information on varieties, mixtures and growing conditions was used as independent variables in a series of meta-regressions. Twenty-six published studies, examining a total of 246 instances of variety mixtures of wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.), were identified as meeting the criteria for inclusion in the meta-analysis; on the other hand, nearly 200 studies were discarded. The accepted studies reported results on both winter and spring types of each crop species. Relative mixing effects ranged from −30% to 100% with an overall meta-estimate of at least 2.7% (p < 0.001), reconfirming the potential of overall grain yield increase when growing varieties in mixtures. The mixing effect varied between crop types, with largest and significant effects for winter wheat and spring barley. The meta-regression demonstrated that mixing effect increased significantly with (1) diversity in reported grain yields, (2) diversity in disease resistance, and (3) diversity in weed suppressiveness, all among component varieties. Relative mixing effect was also found to increase significantly with the effective number of component varieties. The effects of the latter two differed significantly between crop types. All analyzed models had large unexplained variation between mixing effects, indicating that the variables retrievable from the published studies explained only a minority of the differences among mixtures and trials.     

The minimal enzyme cocktail concept for biomass processing

Efficient generation of a fermentable hydrolysate is a primary necessity in the utilization of fibrous plant biomass as a feedstock in bioethanol processes. Enzyme catalyzed hydrolysis of cellulose and heteroxylans in biomass feedstocks each require multiple enzyme activities to achieve degradation to fermentable monosaccharides. The minimal enzyme cocktail concept concerns identification of the minimal number, the minimal levels, and the optimal combination of the best performing key monoactive enzymatic activities to meet this requirement. Two major hypotheses lie behind this concept: 1. That the native multi-component profiles of crude “wild type” cellulolytic and/or xylan degrading enzyme preparations are not optimal for degradation of cellulose in pre-treated lignocellulosic biomass nor for degradation of heteroxylans in hemicellulose-rich product streams; 2. That it is possible to replace crude multienzyme preparations with designed combinations of the minimal number of required enzyme activities for biomass processing. This paper outlines the current strategies employed and the stage of development of minimal enzyme cocktails for enzymatic hydrolysis of cellulose and arabino-xylan in complex, genuine biomass substrates. The available data demonstrate the feasibility of the concept and illustrate the potential efficacy improvements obtainable by use of designed minimal enzyme cocktails for pre-treated lignocellulosic and hemicellulose-rich biomass substrates.     

Impacts of the Kyoto Protocol on boreal forest climate change mitigation

? Context

The Kyoto Protocol allows the use of domestic forest carbon sequestration to offset emissions to a limited degree, while bioenergy as an unlimited emission reduction option receives substantial financial support in many countries.

? Aim

The primary objective of this study was to analyze (1) whether these limits on forest carbon sequestration would be binding, thereby leading to inefficient mitigation, and (2) the total potential effect of the protocol on the greenhouse gas (GHG) fluxes in the forest sector.

? Methods

A partial equilibrium model of the Norwegian forest sector was used to quantify the GHG fluxes in a base scenario with no climate policy, a Kyoto Protocol policy (KP policy), and a policy with no cap on forest carbon sequestration (FC policy), assuming that the policies apply the rest of the century.

? Results

Carbon offsets are higher under the KP policy than in the base scenario and likewise higher than under the FC policy in the short run, but the KP policy fails to utilize the forest carbon sequestration potential in the long run as it provides considerably less incentives to invest in forestry than the FC policy.

? Conclusion

The KP increases the Norwegian forest sector’s climate change mitigation compared to no climate policy but less in the long run than a carbon policy with no cap on forest carbon credits.     

An assessment of forest sector modeling approaches: conceptual differences and quantitative comparison

Forest sector models are widely used for policy and economic analyses. Basic assumptions vary considerably between models, but little attention has been paid to the impacts these differences may have on model results. Norway provides a great opportunity to fill this void as it has two forest sector models currently in use based on different modeling assumptions, but sharing the same data source. In one model, agents are assumed to be myopic in the meaning that they rely only on the current market conditions. Harvest behavior is in this model based on econometric relations and exogenous forest growth rates. The second model approach employs extensive forest data and assumes that agents have perfect information over the model time horizon. We discuss the differences between the two modeling approaches and compare quantitatively the model results of two case studies. However, both types of models are rather sensitive to changes in assumptions and data. The strengths and weaknesses of the two model approaches and their appropriateness for responding to the study questions should be considered when choosing modeling methodology. Using both models in parallel removes the uncertainty caused by the foresight assumption/optimization routine and thus provides in total more information.     

Hematologic and biochemical reference intervals for Norwegian crossbreed grower pigs

Background: Hematologic and biochemical reference intervals depend on many factors, including environment and age. Reference intervals for Norwegian grower pigs are lacking, and previously published reference intervals for similar pigs from other countries are now outdated due to significant changes in management and breeding on the pig farms. Objectives: The aim of this study was to determine updated reference intervals for hematologic and biochemical analytes in healthy crossbred grower pigs, and to compare the results among 3 different farms. Methods: Blood samples were collected from 104 clinically healthy pigs of the most common Norwegian crossbreed (Landrace Yorkshire sow × Landrace Duroc boar). The pigs were 12–16 weeks old, weighed 30–50 kg, of both sexes, and lived on 3 farms in eastern Norway. Automated hematologic and biochemical analysis were performed using ADVIA 2120 and ADVIA 1650 analyzers. Results: Five samples were excluded because of hemolysis (1) or outliers (4). Reference intervals were calculated using parametric or nonparametric methods, depending on data distribution. Mean, median, minimum, and maximum values were tabulated. Conclusions: The reference intervals calculated in this study will be useful for the diagnosis and monitoring of disease in this widespread crossbreed pig. Compared with previously published reference values, reference intervals for total WBC count, creatine kinase and alanine aminotransferase activities, and albumin, bilirubin, and urea concentrations in this study differed notably.     

Bisection of bovine morulae and blastocysts from superovulated Danish dairy cows

Sixtyfour compacted morulae and blastocysts were bisected with a microscalpel. The majority of the demi-embryos (n = 122) were reinserted into separate zona pellucidae (ZP) before non-surgical transfer to 113 synchronized recipients, as singles (n = 98) (DE-S) or in pairs (n = 30) (DE-P). Thirty non-manipulated embryos (E) were transferred during the same period and served as controls. Pregnancies were diagnosed by rectal palpation 4-7 weeks after transfer. The pregnancy rates for DE-S, DE-P and E were 32%, 53% and 40%, respectively (P greater than 0.05). A substantial number of abortions were recorded between 50 and 250 days of pregnancy among the recipients with DE-S. The fetal survival rate for DE-S was reduced to 21% and significantly lower (p less than 0.05) than the survival rates of DE-P (43%) and E (40%). The quality of DE and the presence of ZP did not significantly influence the results. No conclusive reasons for the fetal loss could be found but different possibilities are discussed.