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11.
Effects of liming on chemical properties of soil, needle nutrients and growth of Scots pine transplants 总被引:1,自引:0,他引:1
Anna Saarsalmi Pekka TamminenMikko Kukkola Teuvo Levula 《Forest Ecology and Management》2011,262(2):278-285
The effects of limestone (2.0 and 4.0 Mg ha−1) on chemical properties of soil, nutrient concentrations of needles and growth of Scots pine (Pinus sylvestris L.) transplants were investigated on three reforestation areas on infertile acidic sites in southern Finland. The limestone was applied either on the soil surface (unploughed plots) or was mixed into the topsoil (ploughed plots). All the treatments were replicated four times. Surface broadcast of lime elevated the pH in the organic layer and in the 0-10 cm layer of mineral soil. The increase in the pH of the organic layer after 21 years was, on average, 0.7 and 1.1 pH units, with a dose of lime 2 and 4 Mg ha−1, respectively. On the ploughed plots, the pH in the uppermost 0-10 cm soil layer was 0.4-0.5 units higher than on the corresponding unlimed plots. Both doses of lime significantly increased the amount of exchangeable Ca and the base saturation (BS) in the topsoil on the ploughed plots, and the amount of exchangeable Ca and Mg, as well as the base saturation (BS) in the organic layer + the 0-10 cm layer of mineral soil on the unploughed plots. Regardless of the techniques used for application of lime, after 21 growing seasons the Ca and Mg concentrations in needles were significantly higher on the limed plots than on the controls. In needles, the Ca/Mn ratio was the best indicator for measuring the response to liming. Only on the unploughed plots did liming increase stand volume and dominant diameter of pines. Intensive disc ploughing produced significantly more stems and increased both stand volume and the dominant height of pines compared to unploughed plots. 相似文献
12.
Leaf cuticular surface absorption of O3 was investigated inBetula pendula Roth leaves which have no stomata on their adaxial surface. A two-component absorption model was assumed to approximate experimental data. The first component, having second order kinetics, decreased exponentially during ozonation, the second or residual component remained constant. The residual ozone conductance of the leaf cuticle was about an order of magnitude higher than the leaf cuticular conductance to water vapour. It is concluded that leaf surface absorption must be taken into consideration during short term experiments and in those with low ozone concentrations. 相似文献
13.
14.
Pekka Vähäoja Petteri Piltonen Anna Hyvönen Jouko Niinimäki Jorma Jalonen Toivo Kuokkanen 《Water, air, and soil pollution》2005,165(1-4):313-324
This study focuses on the biodegradability measurements of tall oil-based wood preservatives and their raw materials in groundwater as determined by the respirometric BOD OxiTop method. Certain substances were also analyzed in standard conditions described by OECD 301 F. Results show that creosote oil, a traditional wood preservative, does not biodegrade at all in groundwater over a period of 28 days, while tall oil and linseed oil biodegrade to some degree (13.4% and 14.8%, respectively). On the other hand, degrees of biodegradation of linseed oil, tall oil and creosote oil in the extra mineral and microbe including conditions described by OECD 301 F were 72.9%, 54.3% and 24.9% after 28 days, respectively. Studied raw materials of tall oil-based wood preservative production biodegrade to some degree in groundwater (variability from 11.9% to 18%) and quite effectively in OECD 301 F test (variability from 39% to 71.7%) over a period of 28 days. Abiotic degradation may also be significant with the studied substances. 相似文献
15.
There is a need to introduce soil microbiological methods into long term ecological monitoring programs. For this purpose we studied the impact of moderate anthropogenic air pollution in polluted and less polluted area districts, forest site types Calluna (CT), Vaccinium (VT) and Myrtillus (MT) and the amount of organic matter, measured as carbon content on the soil respiration activity and the ATP content. The main sources of local air pollutants (SO2 and NOx) in the polluted area district were from the capital' region and an oil refinery. Humus (F/H-layer) and the underlying 0 to 5 cm mineral soil samples were collected from 193 study plots located in the 5300 km2 study area. We found that the soil respiration rate in humus layer samples was lower in the polluted area district compared to the less polluted one (16.0 and 19.5 μL CO2 h?1g?1 dw, respectively), but the difference occurred only in the dry, coarse-textured CT forest site type. The mineral soil respiration rate and the mineral soil and humus layer ATP content were not affected, by the air pollution. Most of the variations of the biological variables were explained primarily by the soil carbon content, secondly by the forest site type and thirdly by the area division. 相似文献
16.
Mirja Ruohoniemi DVM Marjatta Karkkainen Dr.med.vet Pekka Tervahartiala MD PhD 《Veterinary radiology & ultrasound》1997,38(5):344-351
Six Finnhorse cadaver forefeet were selected to represent radiographically different types and grades of ossification of the collateral cartilages of the distal phalanx. These cartilages and adjacent tissues were evaluated with computed tomography (CT) and high field magnetic resonance imaging (MRI). In CT the internal structure of the cartilages was consistent, but in MRI some differences were noted. The shape of the collateral cartilages and their ligamentous attachments varied. The border between ossified and non-ossified cartilage appeared distinct, with considerable variation in the extent of the ossified area in regard to the cross-sectional area of the cartilage. Ossification originating from the palmar processes and extending in the proximaVpalmaroproximal direction, without separate centers of ossification, generally appeared smooth and inactive. Palmar ossification followed the irregular shape of the cartilage. Separate centers of ossification had a medullary cavity or were sclerotic. Presence ofamedullary cavity or sclerosis were also found at the base of the cartilages. The incomplete fusion lines between separate centres of ossification and the ossified base of the cartilage varied from congruent and inactive to reactive with marked sclerosis, flared margins and parachondral changes. Incomplete fusion may be clinically significant. Local conformational adaptations of the hoof were also documented with extensive ossification of the collateral cartilage. 相似文献
17.
Egenvall A Bonnett BN Ohagen P Olson P Hedhammar A von Euler H 《Preventive veterinary medicine》2005,69(1-2):109-127
The main objective of this study was to describe the incidence of mammary tumors (MTs) and the survival after MTs, in female dogs between 3 and 10 years of age (insured for veterinary care and with life insurance in a Swedish animal-insurance company) from 1995 to 2002. Measures of incidence are presented crudely, by breed and across age categories and birth cohorts (1991-1998). The survivals until MT diagnosis and after a MT diagnosis were computed. The overall incidence for any MT claim was 111 dogs per 10,000 dog-years at risk (DYAR). The overall MT rate in the 1992 and 1993 birth cohorts was 154 dogs per 10,000 DYAR. The incidence for any MT claim increased with age and varied by breed, from 319 dogs per 10,000 DYAR in the English springer spaniel to 5 dogs per 10,000 DYAR in the rough-haired collie. At the ages 6, 8 and 10 years, 1%, 6% and 13% respectively, of all females had at least one MT claim. The MT mortality was 6 deaths per 10,000 DYAR and increased with age. The overall-case fatality was 6%. 相似文献
18.
A numerical model was developed for the bioaccumulation of mercury (Hg) in fish. The model is based on the bioenergetic calculation of fish growth, food consumption, respiration, specific dynamic action and waste losses (egestion/excretion) using the program of Hewett and Johnson (1992). Based on the predation and food results obtained, the accumulation of Hg in fish is calculated taking into account the concentrations of methyl mercury (MeHg) in food and water, its intake and accumulation from food and from water, and the removal of Hg from the body. Some species at various levels of food web are considered in the multistep model applications. The model is used to compute the changes of Hg contents in perch (as prey) and pike (as predator) caused by the release of Hg from the bottom sediments when the Kokemäki River in Western Finland was dredged. The model results were not far from the observed results even though the forcing conditions had been described only roughly. 相似文献
19.
Rapamycin-induced insulin resistance is mediated by mTORC2 loss and uncoupled from longevity 总被引:2,自引:0,他引:2
Lamming DW Ye L Katajisto P Goncalves MD Saitoh M Stevens DM Davis JG Salmon AB Richardson A Ahima RS Guertin DA Sabatini DM Baur JA 《Science (New York, N.Y.)》2012,335(6076):1638-1643
Rapamycin, an inhibitor of mechanistic target of rapamycin complex 1 (mTORC1), extends the life spans of yeast, flies, and mice. Calorie restriction, which increases life span and insulin sensitivity, is proposed to function by inhibition of mTORC1, yet paradoxically, chronic administration of rapamycin substantially impairs glucose tolerance and insulin action. We demonstrate that rapamycin disrupted a second mTOR complex, mTORC2, in vivo and that mTORC2 was required for the insulin-mediated suppression of hepatic gluconeogenesis. Further, decreased mTORC1 signaling was sufficient to extend life span independently from changes in glucose homeostasis, as female mice heterozygous for both mTOR and mLST8 exhibited decreased mTORC1 activity and extended life span but had normal glucose tolerance and insulin sensitivity. Thus, mTORC2 disruption is an important mediator of the effects of rapamycin in vivo. 相似文献
20.
Seppo Ahvenjärvi Aila Vanhatalo Pekka Huhtanen Tuomo Varvikko 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(3):179-189
Four multiparous dairy cows, fitted with rumen and duodenal cannulas, were fed grass silage and one of four concentrates of barley (B), barley+urea (BU), barley+solvent-extracted rapeseed meal (BRM) or barley+heat-moisture-treated rapeseed cake (BRC). Despite marginal N deficiencies for the control diet (B), BU did not affect milk yield, ruminal fibre digestion or omasal total non-ammonia-N (NAN) or microbial NAN flow. In contrast, BRM and BRC diets significantly increased milk and milk protein yields and omasal dietary NAN flows. Effects of rapeseed meal (RSM) and rapeseed cake (RSC) on milk yield and omasal NAN flow were similar. The diets had no effect on rumen microbial protein synthesis. In general, non-protein N and soluble true protein comprised 0.20 of omasal total NAN flow, for all diets. Supplementary AAT from rapeseed feeds appeared to escape from the rumen as insoluble feed particles. 相似文献