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The spatial variation in the concentrations of various plant nutrients in the above ground biomass was examined in a fertilized and limed59-year-old Norway spruce stand on a nutrient poor soil at Klosterhede, western Denmark. Two types of lime (calcite and dolomite combinedwith additional kieserite and phosphate) were applied alone and in combination with conventional NPK fertilizer to form five different treatments. Sample trees of different size classes were felled and the nutrient concentrations of N, P, K, Ca, Mg and S were analysed at various heights from ground level, dividing the biomass into seven compartments (stem wood, stem bark, living branches, dead branches, current year needles, older needles and cones). The nutrient concentrationswere generally highest in the actively growing parts of the trees (e.g. needles and stem bark). The concentrations of N, P, K and S were generally higher in current year needles than in older needles, whereas the opposite pattern was observed for the concentrations of Mg andCa. The concentrations of N, P, S and Ca were increased by the treatments, most pronounced in the actively growing parts of the trees. However, the concentrations of K and Mg seemed unaffected by the treatments. When N and P were applied, the concentrations in the current year needles were elevated to levels that could be considered above deficiency in all parts of the canopy. Nutrient concentrations did not vary with tree size. [ABSTRACT FROM AUTHOR]

Above ground biomass and nutrient distribution were determined in a combined liming and fertilization in a 59-year-old Norway spruce stand on a nutrient poor soil at Klosterhede, Denmark. Two types of lime (calcite and dolomite combined with additional kieserite and phosphate) were applied alone or in combination with conventional NPK fertilizer. Five sample trees of different size classes were felled in each treatment plot. The biomass was divided in seven compartments: stem wood, stem bark, living branches, dead branches, current year needles,older needles, and cones. The total above ground biomass and nutrient content in each tree were calculated and referenced to the ground surface area by solving regression equations relating the biomass or amount of nutrients to the tree height and breast height diameter (DBH) for all the trees in a given treatment. The biomass was closely correlated to the tree size (height x DBH2) for stem wood, stem bark, living branches, and older needles(R2>/=0.70). The results show that biomass and stem volume growth were not affected (P-1 dry mass). The main part of the N, P, K, Mg, and S was in the living branchesand needles (>60%), while stem bark, living branches, and needles contained a significant part of the Ca (>70%). The accumulation of nutrients in stem bark and needles increased significantly following fertilization and liming, especially in the current year needles. The calculated annual mean accumulation of P in the above ground biomass increased from 2.3kgha-1 for the control plot to more than 5kgha-1 for some of the treatments. [ABSTRACT FROM AUTHOR]

Forest soils harbor hyper-diverse microbial communities which fundamentally regulate carbon and nutrient cycling across the globe. Directly testing hypotheses on how microbiome diversity is linked to forest carbon storage has been difficult, due to a lack of paired data on microbiome diversity and in situ observations of forest carbon accumulation and storage. Here, we investigated the relationship between soil microbiomes and forest carbon across 238 forest inventory plots spanning 15 European countries. We show that the composition and diversity of fungal, but not bacterial, species is tightly coupled to both forest biotic conditions and a seven-fold variation in tree growth rates and biomass carbon stocks when controlling for the effects of dominant tree type, climate, and other environmental factors. This linkage is particularly strong for symbiotic endophytic and ectomycorrhizal fungi known to directly facilitate tree growth. Since tree growth rates in this system are closely and positively correlated with belowground soil carbon stocks, we conclude that fungal composition is a strong predictor of overall forest carbon storage across the European continent., (© 2024. The Author(s).)

This study aimed to simulate oak and beech forest growth under various scenarios of climate change and to evaluate how the forest response depends on site properties and particularly on stand characteristics using the individual process-based model HETEROFOR. First, this model was evaluated on a wide range of site conditions. We used data from 36 long-term forest monitoring plots to initialize, calibrate, and evaluate HETEROFOR. This evaluation showed that HETEROFOR predicts individual tree radial growth and height increment reasonably well under different growing conditions when evaluated on independent sites. In our simulations under constant CO 2 concentration ([CO 2 ] cst ) for the 2071-2100 period, climate change induced a moderate net primary production (NPP) gain in continental and mountainous zones and no change in the oceanic zone. The NPP changes were negatively affected by air temperature during the vegetation period and by the annual rainfall decrease. To a lower extent, they were influenced by soil extractable water reserve and stand characteristics. These NPP changes were positively affected by longer vegetation periods and negatively by drought for beech and larger autotrophic respiration costs for oak. For both species, the NPP gain was much larger with rising CO 2 concentration ([CO 2 ] var ) mainly due to the CO 2 fertilisation effect. Even if the species composition and structure had a limited influence on the forest response to climate change, they explained a large part of the NPP variability (44% and 34% for [CO 2 ] cst and [CO 2 ] var , respectively) compared to the climate change scenario (5% and 29%) and the inter-annual climate variability (20% and 16%). This gives the forester the possibility to act on the productivity of broadleaved forests and prepare them for possible adverse effects of climate change by reinforcing their resilience., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Wood ash is alkaline and contains base-cations. Application of wood ash to forests therefore counteracts soil acidification and recycle nutrients removed during harvest. Wood ash application to soil leads to strong vertical gradients in physicochemical parameters. Consequently, we designed an experimental system where small-scale vertical changes in soil properties and prokaryotic community structure could be followed after wood ash application. A mixed fly and bottom ash was applied in dosages of 3 and 9 t ha -1 to the surface of soil mesocosms, simulating a typical coniferous podzol. Soil pH, exchangeable cations and 16S prokaryotic community was subsequently assessed at small depth intervals to 5 cm depth at regular intervals for one year. Wood ash significantly changed the prokaryotic community in the top of the soil column. Also, the largest increases in pH and concentrations of exchangeable cations was found here. The relative abundance of prokaryotic groups directionally changed, suggesting that wood ash favors copiotrophic prokaryotes at the expense of oligotrophic and acidophilic taxa. The effect of wood ash were negligible both in terms of pH- and biological changes in lower soil layers. Consequently, by micro-vertical profiling we showed that wood ash causes a steep gradient of abiotic factors driving biotic changes but only in the top-most soil layers.

The response of forest ecosystems to increased atmospheric CO2 is constrained by nutrient availability. It is thus crucial to account for nutrient limitation when studying the forest response to climate change. The objectives of this study were to describe the nutritional status of the main European tree species, to identify growth-limiting nutrients and to assess changes in tree nutrition during the past two decades. We analysed the foliar nutrition data collected during 1992-2009 on the intensive forest monitoring plots of the ICP Forests programme. Of the 22 significant temporal trends that were observed in foliar nutrient concentrations, 20 were decreasing and two were increasing. Some of these trends were alarming, among which the foliar P concentration in F. sylvatica, Q. Petraea and P. sylvestris that significantly deteriorated during 1992-2009. In Q. Petraea and P. sylvestris, the decrease in foliar P concentration was more pronounced on plots with low foliar P status, meaning that trees with latent P deficiency could become deficient in the near future. Increased tree productivity, possibly resulting from high N deposition and from the global increase in atmospheric CO2, has led to higher nutrient demand by trees. As the soil nutrient supply was not always sufficient to meet the demands of faster growing trees, this could partly explain the deterioration of tree mineral nutrition. The results suggest that when evaluating forest carbon storage capacity and when planning to reduce CO2 emissions by increasing use of wood biomass for bioenergy, it is crucial that nutrient limitations for forest growth are considered., (© 2014 John Wiley & Sons Ltd.)

Ninety-six patients who had undergone first-time discectomy for herniated lumbar intervertebral discs were consecutively randomized to two physical rehabilitation programs: a program of high-intensity, dynamic back extension and abdominal exercises with occurrence of low back pain being the limiting factor or a traditional program of mild, generally mobility-improving exercises within pain limits. Both groups underwent 14 hours of treatment during a 6-week period 5 weeks after surgery. At 26 weeks' follow-up, results indicated that patients who did the high-intensity exercises experienced greater success with regard to the patient disability-index and work capabilities. After 1 year, a trend that favored the use of intensive exercises could be observed. No differences were found in pain or objective measurements. A rehabilitation program of intensive exercises with occurrence of back pain being the limiting factor appears to increase patient behavioral support, resulting in work capacity improvements and patient self-rated disability levels. The results indicate that a 6-wk, 14-hr postoperative rehabilitation program is inadequate if objective postoperative deficit improvements are the desired goal.

Eight-seven cases of secondary amenorrhoea of more than 6 months' duration developing after treatment with oral contraceptives (group I) were compared with 227 cases of secondary amenorrhoea not preceded by treatment with combined tablets (group II). The two groups were collected during the same period. The average age of the patients was 4 years higher in group I than in group II. Oligomenorrhoea and previously occurred in 30% of group I and in 46% of group II. Pronounced predisposing factors., such as psychogenic trauma and stress with or without considerable change in body weight, were encountered in 26% in group I and 56% in group II. The incidence of increased urinary output of 17-keto steroids, 17-ketogenic steroids and of hirsutism was slightly higher in group II. The percentage of eosinophilic cells in vaginal scrapings was low in 20% in group I as compared with 46% in group II. Spontaneous return of pituitary-ovarian function occurred in 40% in both groups. Patients recovering spontaneously in group I presented a maximum during the first few months, followed by a steady and fairly uniform decline. Spontaneous recovery in group II was more or less independent of time. It seems reasonable to believe that oral contraceptives did promote or contribute to the development of secondary amenorrhoea in about 50%, representing cases with various predisposing factors. A causal relation between oral contraceptives and secondary amenorrhoea was indicated in the remaining 50% because of perfectly normal ovarian function before treatment and absence of predisposing factors.

Six cases of pelvic endometriosis were treated with Danazol 400 mg daily for six months. In four of these cases, intestinal endometriosis of varying severity was also present. The initial results were very satisfactory except in one case with adenomyosis and continuous spotting. Follow-up after cessation of treatment suggests that in some cases a further period of treatment will be necessary.

A unique malformation of the vagina with a tiny fistula between an upper and a lower segment of the vagina is presented with a brief summary of the theories concerning the development of the vagina.

The association between clinical findings and the occurrence of spermagglutinating antibodies was investigated in serum from women in 326 consecutive infertile couples. No relationship was found between unexplained infertility and the occurrence of sperm antibodies as detected by the tray agglutination technique. The occurrence of pregnancy at follow-up was the same in women with and without circulating sperm antibodies. However, the cumulative probability of conception per year was significantly lower in women with spermagglutinating antibodies than in women without such activity (0.005 greater than 2 P greater than 0.001), and the results showed a positive correlation between the duration of infertility and the occurrence of sperm antibodies. The latter findings may either reflect a fertility-reducing effect of the sperm antibodies or represent a time-related increasing tendency to develop sperm antibodies secondarily to the infertility.