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| 1 | Height increment of understorey Norway spruces under different tree canopies显示文摘Background:Stands having advance regeneration of spruce are logical places to start continuous cover forestry(CCF) in fertile and mesic boreal forests.However,the development of advance regeneration is poorly known.Methods:This study used regression analysis to model the height increment of spruce understorey as a function of seedling height,site characteristics and canopy structure.Results:An admixture of pine and birch in the main canopy improves the height increment of understorey.When the stand basal area is 20 m2ha-1 height increment is twice as fast under pine and birch canopies,as compared to spruce.Height increment of understorey spruce increases with increasing seedling height.Between-stand and within-stand residual variation in the height increment of understorey spruces is high.The increment of 1/6 fastest-growing seedlings is at least 50%greater than the average.Conclusions:The results of this study help forest managers to regulate the density and species composition of the stand,so as to obtain a sufficient height development of the understorey.In pure and almost pure spruce stands,the stand basal area should be low for a good height increment of the understorey. | Olavi Laiho Timo Pukkala Erkki Lhde1 | 2014 | Forestry Studies in China2014，16，1： | 5 |
| 2 | Optimizing any-aged management of mixed boreal forest under residual basal area constraints显示文摘The current trend of forest management in many countries is reduced use of clear-felling and planting, and increased use of continuous cover management. In Finland, the new forest act of 2014 made all types of cuttings equally allowable on the condition that if the post-cutting residual stand basal area is too low, the stand must be regenerated within certain time frame. Forest landowner can freely choose between evenand uneven-aged management. This study developed a method for optimizing the timing and type of cuttings without the need to categorize the management system as either even-aged or uneven-aged. A management system that does not set any requirements on the sequence of post-cutting diameter distributions is called any-aged management. Planting or sowing was used when stand basal area fell below the required minimum basal area and the amount of advance regeneration was less than required in the regulations. When the cuttings of 200 stands managed earlier with even-aged silviculture were optimized with the developed system, final felling followed by artificial regeneration was selected for almost 50% of stands. Reduction of the minimum basal area limit greatly decreased the use of artificial regeneration but improved profitability, suggesting that the truly optimal management would be to use natural regeneration in financially mature stands. The optimal type of thinning was high thinning in 97–99 % of cases. It was calculated that the minimum basal area requirement reduced the mean net present value of the stands by 12–16 % when discount rate was 3–5 %. | Timo Pukkala Erkki L?hde Olavi Laiho | 2014 | Journal of Forestry Research2014，25，3： | 5 |
| 3 | Relationships between native tree species and soil properties in the indigenous forest fragments of the Eastern Arc Mountains of the Taita Hills, Kenya显示文摘The relationship between soil properties and spatial distribution of native woody species was studied in three Taita Hills forest fragments which, although degraded, are ranked among 34 biodiversity hotspots of the world due to their high biodiversity of both plant and animal species. This relationship was assessed by using Spearman correlation and principal component analyses (PCA). The results of these analyses should be useful in instituting forest restoration programs that are crucial for the forests. Both the soil and vegetation studied were sampled from 17 subplots in the natural forest fragments of Ngangao (120 ha), Chawia (86 ha) and Mbololo (185 ha). The soil variables measured were: pH, texture, soil nutrients of C, N, Ca, P, K, Mg and Na. In total 36 native tree species from 13 families were identified from the three forest fragments. Ordination results show that axis 1 accounted for 35% and axis 2 for 25% of the total variation in species composition, indicating that the structure of vegetation is related to two major environmental gradients. The correlation analyses of species and soil properties showed that Na and clay particles were the most important determinants of species distribution; pH and soil variables such as C, N, Ca and P also played minor roles. Unexpectedly, some species (e.g. Psychotria petitii) showed positive relationships with Na attributed to possible substitution for K. Relationships with P were both positive (e.g. Craibia zimmermannii) and negative (e.g. Albizia gummifera) with some species, attributable to pH levels. An ANOVA for soil variables showed that there were differences in the Ca content in Mbololo (due to the parent material) and P in Ngangao where a special relationship was observed between some of the species. The presence of gaps accounted for the distribution of seedlings but not for the saplings, whose distribution responded more to factors similar to those to which mature trees respond. Soil-species relationships that were established may be utilized along with soil analyses when choosing native species for restoration. | Loice Mildred Akinyi OMORO Raija LAIHO Michael STARR Petri K.E.PELLIKKA | 2011 | Forestry Studies in China2011，13，3： | 2 |
| 4 | Long-term effects of water level drawdown on the vegetation of drained pine mires in Southern Finland显示文摘 | Laine J Vasander H Laiho R | 1995 | Journal of Applied Ecology1995，32，4： | 1 |
| 5 | Strength and strength retention in vitro of absorbable self- reinforced polyglycolide (PGA) rods for fracture fixation 显示文摘 | Vainionpa S Kilpikari J Laiho J | 1987 | Biomaterials1987，8，： | 1 |
| 6 | Development of Norway spruce dominated stands after single- IIee se- lection and low thinning显示文摘 | Lahde E laiho O Nomrpi Y | 2002 | Can J For Res2002，32，： | 1 |
| 7 | Finnish HLA studies confirm the increased risk conferred by HLA-B27homozygosity in ankylosing spondylitis显示文摘 | Jaakkola E Herzberg I Laiho K | | 0，，06： | 1 |
| 8 | Preservation of venousvalve fimction after catheter-directed and systemic thrornbolysisfor deep venous thrombosis显示文摘 | Laiho MK Oinonen A Sdgano N | 2009 | Eur J Vase Endovase Surg2009，，28： | 1 |
| 9 | TGF-β induction of type-1 plasm in ogen activator inhibitor显示文摘 | Laiho M Saksela O Keskr Oja L | 1987 | JB iol Chem1987，262，17： | 1 |
| 10 | Human cell surface glycoprotein related to cell proliferation is the receptor for transform显示文摘 | Cheifetz S Hemandez H Laiho M | 1990 | Journal of Biology Chemistry1990，265，20： | 1 |
| 11 | Finnish case-control and family studies support PTPN22 R620W polymorphism as a risk factor in rheumatoid arthritis, but suggest only minimal or no effect in juvenile idiopathic arthritis显示文摘 | Seldin MF Shigeta R Laiho K | 2005 | Genes Immun2005，6，8： | 1 |
| 12 | CNN applications from the hardware point of view: Video sequence segmentation 显示文摘 | Kananen A Paasio A Laiho M | 2002 | International Journal of Circuit Theory and Applications2002，30，： | 1 |
| 13 | Resonant cancellation of Brillouin scattering near the indirect gap of a-ZnPz 显示文摘 | Karajamaki E Laiho R Levola T | 1980 | J Phys C: Solid State Phys1980，13，20： | 1 |
| 14 | Diversity-oriented silvicultures in boreal zone of Europe显示文摘 | Lahde E Laiho O Norokorpi Y | 1999 | Forest Ecology and Management1999，118，： | 1 |
| 15 | Rise in serum C reactive protein after hip and knee arthroplasties in patients with rheumatoid arthritis显示文摘 | Laiho K M(a)enp(a)(a) H Kautiainen H | | 0，，03： | 1 |
| 16 | helical computerized tomography and nt-probnp for screening of right ventricular over- load on admission and at long term follow-up of acute pulmonary embolism显示文摘 | Laiho MK Harjola VP Graner M | 2012 | Scand J Trauma Resusc Emerg Med2012，20，： | 1 |
| 17 | Growth and yield models for une- ven-sized forest stands in Finland显示文摘 | Pukkala T Lahde E Laiho O | 2009 | Forest Ecology and Manage- ment2009，258，3： | 1 |
| 18 | Genome-wide allelotyping of 104 Finnish colorectal cancers reveals an excess of allelic imbalance in chromosome 20q in familial cases显示文摘 | Laiho P Hienonen T Karhu A | 2003 | Oncogene2003，22，14： | 1 |
| 19 | Development of Norway spruce dominated stands after single-tree selection and lowthinning显示文摘 | Lahde E laiho O Nororpi Y | 2002 | Can J For Res2002，32，： | 1 |
| 20 | GaAs/AlGaAs双量子阱中量子相干特性的研究显示文摘研究了低温、平行磁场下两种GaAs/AlGaAs双量子阱的量子干涉特性.两种样品的阱宽均为60,但挚垒层厚度不同,分别为120和20.实验结果表明,样品的电导随磁场呈周期性振荡,振荡周期近似为h/(e·S),这一结果同Aharonov-Bohm效应的理论值相吻合。我们也发现,薄势垒层样品比厚势垒层样品的电导振荡幅度更大一些. | 王杏华 郑厚植 李承芳 刘剑 杨小平 余琦 Reino Laiho | 1994 | Journal of Semiconductors1994，15，10： | 1 |
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