Future management options for cembran pine forests close to the alpine timberline

Key message

High-elevation forests in the Alps protect infrastructure and human lives against natural hazards such as rockfall, flooding, and avalanches. Routinely performed silvicultural interventions maintain the required stand structure but are not commercially viable in remote forests due to high operational costs. Financial subsidies for the management of high-elevation protection forests are an efficient strategy to ensure sustainable forest cover.

Context

Presently, many high-elevation forests in the Alps are managed in order to ensure the provision of ecosystem services with emphasis on the minimization of natural hazards.

Aims

We studied the possible economic performance of a high-elevation protection forest from an owner’s perspective. We investigated whether the increase in productivity due to climate change and a favorable market for the dominating cembran pine (Pinus cembra L.) are sufficient for profitable timber production in protection forests.

Methods

We simulated the standing timber stock and the soil carbon pool for a 100-year period with climate-sensitive models and compared harvesting costs with expected revenues. Our scenarios included different climates, intensities of timber extractions, parameters of the timber market, and the availability of government subsidies.

Results

Overall, the productivity of forests increases by approximately 15% until the end of the century. In a zero-management scenario, the forest accumulates carbon both in the aboveground biomass and the soil. In the case of an extensive management with moderate timber extractions every 50 years, the carbon stocks decline both in biomass and soil. A more intensive management scenario with extractions every 30 years leads to substantial losses of the soil and biomass carbon pools. In addition, the stand structure changes and the protective function of the forest is not sustainably ensured. Timber production can be economically successful only with high selling prices of cembran pine timber and the availability of governmental subsidies for forest management. The admixed European larch (Larix decidua Mill.) contributes only marginally to the economic success. The main challenge are harvesting costs. The costs of timber extraction by a long-distance cableway logging system exceed the value of the harvested timber.

Conclusion

The intensification of forest management cannot be recommended from the perspective of timber production, sustainable forest management, and protection against natural hazards. Our simulation experiment shows that the extraction of timber at decadal intervals depletes the carbon stock that is insufficiently replenished from aboveground and belowground litterfall. Leaving the forest unmanaged does not impose a particular threat to stand stability and is under the encountered situation, a justified strategy.

     

Differentiation of <Emphasis Type="Italic">Glycyrrhiza uralensis</Emphasis> Fisch. ex DC. populations in the Bulgan River Basin,Western Mongolia

Glycyrrhiza uralensis Fisch. ex DC. (Chinese licorice) is an important medicinal plant in Mongolia. Despite its traditional role in local healing systems, little is known about the existing intra-specific diversity of this species. The aim of the present study therefore was to analyze morphological and genetic diversities of G. uralensis in the Bulgan River Basin in Western Mongolia and to test different treatments aimed at breaking seed dormancy in order to facilitate effective cultivation of this species. Morphological measurements were taken and leaf and seed samples were collected in eight populations of the Bulgan River Basin. Subsequently, DNA was extracted from leaves and analyzed employing amplified fragment length polymorphisms. A total of 11 treatments were used to test and enhance seed germination. Morphological characteristics differed among populations. Treatments used in the study affected total emergence and mean days to germination of the seeds differently, but populations did not differ in their response whereas differentiation within populations was high. Mechanical and acid scarifications were more effective compared to other treatments. The level of genetic diversity in the studied populations was lower than the average value of the short-lived perennial herbs, but close to that of the self-breeding species. Most of the genetic variation was within populations. Chinese licorice is suitable for cultivation in the Bulgan River Basin and effective scarification can increase germination of seeds across the populations collected in our study area.     

15N-labelled fertiliser recovery by maize (Zea mays L.) and leaching of nutrients as influenced by oil palm empty fruit bunch biochar in a mini-lysimeter under controlled tropical environment

Converting oil palm empty fruit bunches into biochar is an alternative waste management method and has strong potential to improve N fertiliser use efficiency in agriculture. The aim of this study was to determine the effectiveness of oil palm empty fruit bunch biochar (EFBB) in improving recovery of ¹⁵N-labelled nitrogen fertiliser by maize (Zea mays L.) and leaching of mineral N and K. An experiment was conducted in a mini-lysimeter system with randomised complete block design layout and six replications under controlled environment in a rain shelter. Each mini-lysimeter was filled with 20 kg of sandy loam soil before adding EFBB (0, 5, 10 and 20 Mg ha^?1). The N source used was (¹⁵NH₄)₂SO₄ at 80 kg N ha^?1 (2 at% ¹⁵N excess). Maize was irrigated to induce leaching every 4 days. Maize plant and soils were sampled 58 days after sowing (tasselling stage). Application of EFBB significantly reduced cumulative leachate volume and mineral N leaching. Soils applied with EFBB significantly improved ¹⁵N fertiliser recovery in maize and dry matter weight. This study shows that EFBB has the potential to be applied on highly weathered acidic soil as an amendment to improve fertiliser efficiency and crop growth.     

SSR fingerprinting of a German <Emphasis Type="Italic">Rubus</Emphasis> collection and pedigree based evaluation on trueness-to-type

Eighty-two genotypes of Rubus available in germplasm collections, nurseries and home gardens were collected and evaluated using a set of 16 simple sequence repeat (SSR) markers to estimate the level of genetic diversity and relatedness of the germplasm and for testing them on trueness-to-type. Each of the 16 SSRs was successful in amplifying alleles from most genotypes. Fifteen of the markers produced polymorphic bands, whereas marker RhM023 was monomorphic. The polymorphic information content among genotypes varied from 0.056 to 0.83 with an average of 0.348. A neighbor-joining analysis allocated the genotypes to four major clusters containing 11, 24, 39 and eight genotypes, respectively. Cluster I consists of floricane-fruiting cultivars originating from the Scottish and/or British breeding programs or cultivars which have those cultivars in their pedigree. Cluster II included cultivars that have ‘Autumn Bliss’ or ‘Tulameen’ in their pedigree. Cluster III consists of summer-bearing raspberry cultivars, some primocane-fruiting cultivars, and a few intermediate summer-fall-bearing types. Cluster IV consists of the blackberry ‘Navaho’ (R. fruticosus L.), the interspecific hybrid ‘Dorman Red’ and a few other raspberry varieties. A number of yellow fruited varieties was dispersed on three different clusters suggesting a convergent evolution of this trait. The pedigree of several genotypes could be confirmed using a Pedimap based approach, whereas other cultivars were found to be genetically identical. The results disclose the alarming narrow genetic base of Rubus resources in Germany. Broadening of this base is urgently needed.     

Long-term amendment of four different compost types on a loamy silt Cambisol: impact on soil organic matter,nutrients and yields

This study investigated the long-term effects of different composts (urban organic waste compost (OWC), green waste compost (GWC), cattle manure compost (MC) and sewage sludge compost (SSC)) compared to mineral fertilisation on a loamy silt Cambisol, after a 7-year start-up period. The compost application rate was 175 kg N ha^?1, with 80 kg mineral N ha^?1 and without. Soil characteristics (soil organic carbon (SOC), carbon-to-nitrogen (C/N) ratio and soil pH), nutrients (nitrogen (N), phosphorous (P) and potassium (K)) and crop yields were investigated between 1998 and 2012. SOC concentrations were increased by compost applications, being highest in the SSC treatments, as for soil pH. N contents were significantly higher with compost amendments compared to mineral fertilisation. The highest calcium-acetate-lactate (CAL)-extractable P concentrations were measured in the SSC treatments, and the highest CAL-extractable K concentrations in the MC treatments. Yields after compost amendment for winter barley and spring wheat were similar to 40 kg mineral N ha^?1 alone, whereas maize had comparable yields to 80 kg mineral N ha^?1 alone. We conclude that compost amendment improves soil quality, but that the overall carbon (C) and N cycling merits more detailed investigation.     

Element concentrations and storage in the aboveground biomass of limed and unlimed Norway spruce trees at Höglwald

Twenty years after the application of dolomitic limestone to a well growing, mature Norway spruce stand at Höglwald, Southern Germany an amount of magnesium equal to the input by liming has left the rooting zone. However, 80% of the applied calcium was retained by the ecosystem. A detailed biomass investigation was carried out in order to elaborate whether the stand shows any nutritional benefits and if the aboveground tree biomass represents a sink for calcium and magnesium after liming. Stem wood, bark, branches, twigs, and needles were analysed for the major nutrients. Needles showed higher calcium and magnesium concentrations and significantly lower potassium concentrations on the limed plot. Surprisingly, limed trees had significantly lower magnesium concentrations in the bark but higher concentrations in twigs and needles than unlimed trees. In addition, significantly lower concentrations for potassium, sulphur, and phosphorus were measured in the bark of limed trees, whereas the element concentrations in the wood were rather similar between the two treatments. The low potassium concentrations in bark and needles indicate an impeded potassium uptake after liming presumably due to a calcium potassium antagonism. Magnesium is probably used to compensate the relative lack of potassium. The small differences in the calculated nutrient storage of limed and unlimed trees, however, suggest that the aboveground biomass can be excluded as a relevant sink for the applied calcium and magnesium at the Höglwald site.     

Residue distribution of the acaricide coumaphos in honey following application of a new slow-release formulation

Acaricide used in beehives for the control of varroa often leaves residues in bee products. The behaviour and distribution of the acaricide coumaphos in honey following the application of a new slow-release strip formulation (CheckMite+) was assessed. The bee colonies were allowed to build new combs without foundation, and two strips were hung in the brood chamber of each colony for a period of 42 days. The distribution of coumaphos residues in honey in relation to the position of the frame and the duration of treatment was examined by collecting samples from each comb at various time intervals up to 145 days after treatment. In the brood chamber, coumaphos was incorporated into honey from the first day of application, and residues accumulated mainly in combs placed next to strips. In the adjacent combs, residues remained at low concentrations with slight variations. In the honey chamber, residue concentrations on the day of strip removal ranged between 0.006 and 0.020 mg kg(-1), while 79 days after application the concentration of coumaphos residues was below 0.020 mg kg(-1). Residues above the EC fixed maximum residue limit (MRL) of 0.1 mg kg(-1) were measured only in brood chamber honey obtained from those combs placed next to strips. In these samples, 0.060-0.111 mg kg(-1) of coumaphos was detected up to 103 days after strip removal. Coumaphos residues in honey extracted from combs that were placed at the edge of the brood chamber were found below the MRL value, even during the 42 day period of CheckMite+ strip treatment.     

Abnormal motor activity during anaesthesia in a dog: a case report

Seizures or convulsions that occur during anaesthesia in veterinary patients are infrequently reported in the literature. Consequently, the incidence of such events is unknown. Several drugs commonly used in clinical veterinary anaesthesia have been shown to induce epileptiform activity in both human clinical patients and experimental candidates. The present case report describes convulsions in a four-year old male Bernese mountain dog during maintenance of anaesthesia with isoflurane after premedication with acepromazine and methadone followed by co-induction with propofol and ketamine. The dog had no history of previous convulsions. The use of several sedative and anaesthetic drugs makes it difficult to find one single causative pharmaceutical.     

The detection and biotransformation of guanabenz in horses: a preliminary report

Guanabenz (2,6-dichlorobenzylidene-amino-guanidine) is a centrally acting antihypertensive drug whose mechanism of action is via alpha2 adrenoceptors or, more likely, imidazoline receptors. Guanabenz is marketed as an antihypertensive agent in human medicine (Wytensin tablets, Wyeth Pharmaceuticals). Guanabenz has reportedly been administered to racing horses and is classified by the Association of Racing Commissioners International as a class 3 foreign substance. As such, its identification in a postrace sample may result in significant sanctions against the trainer of the horse. The present study examined liquid chromatographic/tandem quadrupole mass spectrometric (LC-MS/MS) detection of guanabenz in serum samples from horses treated with guanabenz by rapid i.v. injection at 0.04 and 0.2 mg/kg. Using a method adapted from previous work with clenbuterol, the parent compound was detected in serum with an apparent limit of detection of approximately 0.03 ng/ml and the limit of quantitation was 0.2 ng/ml. Serum concentrations of guanabenz peaked at approximately 100 ng/ml after the 0.2 mg/kg dose, and the parent compound was detected for up to 8 hours after the 0.04 mg/kg dose. Urine samples tested after administration of guanabenz at these dosages yielded evidence of at least one glucuronide metabolite, with the glucuronide ring apparently linked to a ring hydroxyl group or a guanidinium hydroxylamine. The LC-MS/MS results presented here form the basis of a confirmatory test for guanabenz in racing horses.