Studies on insects and mites causing galls on the leaves of lime treeTilia cordata Mill. in the Ojców National Park in Poland

Analytical studies were conducted on the species composition of galls occurring on the leaves ofTilia cordata Mill. in the Ojców National Park in 1997–1998. The species composition of galls was identical in two years. Galls were caused by 6 species. The most numerous species wereEriophyes leiosoma (Nalepa) in 1997 andPhytoptus tetratichus tetratrichus Nalepa in 1998. Index of occurrence frequency and Agrell’s index of species co-existence have been calculated. This index reached the highest values in both years in case ofE. leiosoma andP. tetratrichus tetratrichus.     

Studies on insects and mites causing galls on the leaves of common ash <Emphasis Type="Italic">Fraxinus excelsior</Emphasis> L. in the Ojców National Park in Poland

The occurrence frequency of galls caused by insects and mites on the leaves of Fraxinus excelsior L. was investigated, based on leaf samples collected in the Ojców National Park in 2000?–?2001. The species composition of galls was identical in two consecutive years. Galls were caused by 5 species a total of 2881 galls. The most numerous species was Dasineura fraxinea (Kieffer) in both years.Index of occurrence frequency and Agrell's index of species co-existence have been calculated. This index reached the highest values in case of Dasineura fraxinea and Vasates fraxini (Nalepa) in 2000 as well as D. fraxinea and Psyllopsis fraxini (L.) in 2001.     

Relationships between the number of dwarf shoots of<Emphasis Type="Italic"> Larix decidua</Emphasis> Mill. damaged by different insect species in the Ojców National Park in southern Poland

A study was conducted on the interrelationships between the number of dwarf shoots of Larix decidua Mill. damaged by insects: Adelges laricis Vall. Coleophora laricella Hbn., Spilonota laricana Hein. and Dasineura kellneri (Hensch.). The study made use of dwarf shoots collected at three sites in the Ojców National Park, southern Poland during 2002–2003. A total of 240 branches with 19,239 dwarf shoots, collected from 60 larches were designated to the study. The data obtained were subjected to statistical analysis using the Spearman rank correlation coefficient and the Students t-test at the 0.05 level. No unequivocal correlation was found between the relationships.     

Elevated temperature effects on germination and early growth of European aspen (Populus tremula), hybrid aspen (P. tremula × P. tremuloides) and their F2-hybrids

This study aimed to understand the interaction between temperature and genotype in terms of the effect on early seedling development of European aspen (Populus tremula) and various F₂-aspen hybrids. We evaluated the response of 16 different European aspen and F₂-hybrid families on seed germination, survival rate and seedling height in one- and two-family trials under three different temperature regimes. In one-family trials, higher germination and higher survival rates were observed in higher temperature (C1700), leading to taller seedlings. European aspen × hybrid aspen individuals (Asp × Hyb) had a higher survival rate and taller seedlings than Asp, Hyb × Asp or Hyb × Hyb individuals. The difference between Asp × Hyb and Hyb × Asp was pronounced. Both growth conditions and genotype (i.e., hybrid cross) had strong effects on germination, survival rate and height of European aspen and F₂-hybrid seedlings. However, the interaction of genotype and growth conditions also had a significant influence on survival rate and seedling height, but not on germination. Two-family trials involving European aspen and F₂-hybrids led to significant negative effects on germination and survival rate and also facilitation effects on seedling height. Similarly, genotype had strong effects on germination and survival rate. Different genotypes and traits affected survival rate and seedling height differently in different growth conditions. These differences were more pronounced in the warmest environment, i.e., 1,700 degree days. We conclude that introgression between F₂-hybrids and local European aspen is likely in the current climate, and any warming will likely favor certain F₂-hybrids, especially the most probable types (P. tremula × (P. tremula × P. tremuloides)).     

Floristic diversity and carbon stocks in the periphery of Deng–Deng National Park,Eastern Cameroon

Carbon is continuously being removed from the atmosphere by photosynthesis and stored in carbon pools(live,dead,and soil carbon)of forest ecosystems.However,carbon stock in dead wood and of trees with diameters at breast height(dbh)between 5 and 10 cm is often not considered in many studies carried out in the Congo Basin Forest.The relationship between tree diversity,life-forms and carbon stocks has received little attention.This study was carried out on the outskirts of Deng Deng National Park(DDNP)to determine tree diversity(dominant families,species richness and Shannon index),assess carbon stocks in the five carbon compartments(living tree,understory,fine roots,dead wood and litter)as well as to analyze the relationship between(1)carbon stocks and tree diversity;and,(2)between carbon stock and life-forms.The Shannon index of trees≥10 cm dbh ranged from 2.6 in riparian forest to 4.3 in secondary forest;and for the tree between 5 and 10 cm,it ranged to 1.56 in riparian forest to 3.68 in the secondary forest.The study site housed 16 species,7 genera and 3 families which are only found in trees of dbh between 5 and 10 cm.The average total carbon stock of the five compartments varied from 200.1 t ha-1 in forest residues to 439.1 t ha-1 in secondary forest.Dead wood carbon stock varied from 1.2 t ha-1 in riparian forests to 12.51t ha-1 in agroforests.The above ground carbon stocks for trees with diameter between 5 and 10 cm varied from 0.7 t ha-1 in young fallow fields to 5.02 t ha-1 in old secondary forests.This study reveals a low but positive correlation between species richness and total carbon stocks,as well as a significant positive relationship between life-forms and total carbon stocks.The findings highlight the need for more data concerning carbon content of dead wood,carbon of trees≥5 cm<10 cm dbh and the relationship between carbon stocks and tree diversity from other areas of the Congo Basin for a good understanding of the contribution of tropical forests to climate change mitigation.     

Genetic and historical studies on the origin of Norway spruce in Białowieża Primeval Forest in Poland

Białowieża Primeval Forest lies within the boreal part of the Norway spruce range, which, according to pollen data, was formed by a refugium located in the Russian Upland. However, recent genetic studies have indicated that spruce from the Eastern Carpathian refugium also occurs in Białowieża Forest. In order to investigate whether the Norway spruce from the Eastern Carpathian refugium migrated naturally into the boreal part of the Norway spruce range, we assessed the refugial origin of 234 of the oldest Norway spruce individuals from Białowieża Forest using mitochondrial marker mt15-D02. Out of the trees that we studied, 64.8% carried mitotype 1, which is specific to the Carpathian refugium, while 35.2% had mitotype 3, specific to the Russian refugium. Our genetic analysis, combined with historical data on forest management in this part of Europe, argues for a natural contribution of spruce from the Eastern Carpathian refugium during postglacial recolonization of Białowieża Primeval Forest.     

Pheromone trapping of the spruce seed mothCydia strobilella L. (Lep., Tortricidae) in southern Poland in 1996–1997

Results of testing of three formulations of sex pheromone analogue ofCydia strobilella L. (Lep., Tortricidae) are given. The studies were carried out from 1996 to 1997 in the Beskid Śląski Mountains being under effect of industrial emissions and the Beskid Żywiecki Mts. almost free of such effect. Traps were hung in spruce stands at every 100 m in altitude between 700 m and 1200 m above the sea level. During studies 3054 moths ofC. strobilella were trapped including 2458 in the Beskid Śląski Mts. Concentration Cs3−Z8−C12:OH-100 was the best formulation of the pheromone. Trapping results using this formulation (1947 moths) were statistically analized. There were no significant differences between the numbers of moth trapped at different altitude in both areas. However, there were significant differences in case of trapping in the Beskid Śląski Mts. in 1997, but at the 0.06 level. Part of investigations under the problem G P06M00108.     

The impact of climate,drainage and fertilization on the survival and growth of pinus sylvestris L. in afforestation of open,low‐production peatlands

The objective of this study was to analyse the conditions for forest production on open, low‐production peatlands in Sweden with respect to climate, and water and nutrient regimes. The study focused on survival and growth of Scots pine (Pinus sylvestris L.) seedlings, planted 18 yrs ago in five experimental areas evenly distributed between south and north Sweden. Different ditch spacing and NPK fertilizer treatments were combined systematically in all experiments. Survival was positively correlated with temperature sum, fertilization and drainage intensity. Tree growth was not influenced by variations in temperature sum after merely draining, but in combination with fertilization, growth was strongly correlated with climate. In the southern experiments, fertilization increased stand growth eight to nine times, whereas stands on the northern sites did not respond to fertilization. The most important fertilizer element was P. The application of N had no effect on growth. More intensive drainage increased stand growth by 60%. In the southern areas, height development in the most intensive drainage and fertilizer treatments indicates a mean annual increment of 6–7 m³ ha^?1, and no sign of decline in growth was seen. Turf‐planting had positive effects on both survival and growth, especially in less intensively drained plots. A large proportion of damaged trees was observed in the experiment. The frequency of damaged trees was positively correlated with treatment intensity but negatively correlated with temperature sum. The results show clearly that merely draining is not sufficient for successful afforestation of low‐production peatland sites. Fertilization by P and K is a necessary prerequisite, but the effect of fertilization varies with climatic conditions, probably owing to the amount of plant‐available N.     

Irradiance in young stands of picea abies (L.) karst. and pinus sylvestris L. and the possibilities to prevent suckers of broad‐leaved trees

Incoming shortwave global radiation (Q _g) and photosynthetically active radiation (PAR; Q _pa as a fraction of full daylight, relative irradiance (%Q), were measured at the same time in young stands of Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.). Measurements were made on three levels above ground: 20 cm above ground and 50 and 15 % of stand height. Stands of three heights (75, 150 and 300 cm) were studied during two months. The stands were created by arranging young trees cut from natural stands, in nine quadratic spacings: 0.1, 0.2, 0.3, 0.4, 0.5, 0.7, 1.0, 1.4 and 2.0 m. The leaf area index (L) was estimated. Differences in %Q‐values for Q _pa and Q_g in the same species and at the same stand height and level of light measurements above ground were significant only in 150 and 300 cm stands. In 75 cm high stands of Scots pine, the %Q was <60% at spacings <0.2 m and in 75 cm high stands of Norway spruce, the %Q was <60% at spacings <0.3 m. Only at 0.1x0.1–0.3x0.3 m, %Q was <20% in Norway spruce stands. In 150 cm stands %Q<20% was measured at spacings <0.7 m in Norway spruce and <0.5 in Scots pine. In 300 cm stands of Norway spruce it was measured up to 1.2 and in Scots pine <1.1 m. Light extinction coefficients, K and K_g for spruce and pine stands were 0.17–0.40 and 0.16–0.31 respectively. Some practical implications of the study are presented. Lack of light (%Q<10%) as a single factor of seriously suppressed growth and development of broad‐leaved plants and suckers by competition in young stands of spruce and pine only occur in dense stands 0.3x0.3 m‐1.1xl.l m (8000–100000 stems/hectare). Competition by light on a regenerated area generally occurs in the level of 50% of tree height (150–300 cm) and higher due to the rapid growth of broad‐leaved trees (sprouts) compared with planted conifers but the light intensity at these levels %Q>10%.     

Forest-based betel leaf and betel nut People in Bangladesh： approach Lawachara National Park （LNP） farming of the Khasia indigenous to biodiversity conservation in

An exploratory survey was conducted among the Khasia living in Lawachara National Parkt （LNP） to investigate their depend- ency on the protected area （PA） for livelihoods, betel leaf hill farming, traditional forest conservation and perceptions of the PA, Field data were collected by interviewing 48 household heads from two villages （punjis） located inside the LNP and visiting their farms.： The economy of the Khasia was forest-based. They were largely dependent on betel leaf hill farming in LNP and nearly 71% of their mean annual income was de- rived from this irrespective of farmer category. On average, about 14% of the incomes of the poorer farmers came from forest produce followed by 10% and 6% for medium and rich farmers respectively. Hills and forests were the foundations of their lives and livelihoods, and LNP was the life-blood of Khasia survival. As a sustainable production system, this farming practice plays a vital role in conserving biodiversity in LNP and might be replicated elsewhere.     

Long‐term effects of temperature on the wood production of Pinus sylvestris L. and Picea abies (L.) Karst. In old provenance experiments

Old provenance experiments with Scots pine and Norway spruce in Finland were used for assessing the long‐term effects of the projected climatic change on forest trees. The northernmost origins showed an increase in wood production when transferred southwards into a climate with an annual mean effective temperature sum close to that which is expected in northern areas as a result of the projected climatic change. A model is constructed with the estimated changes in wood production as a function of the annual mean temperature sum at the original location and the change in the annual mean temperature sum caused by the geographical transfer. The major changes in wood production are expected to occur in the northernmost areas of tree growth.     

Effects of wet–dry cycling on the mechanical properties of Arundo donax L. used for the vibrating reed in woodwind instruments

Wood Science and Technology - The effects of wet–dry and moist–dry cycling on the mechanical properties of reed (Arundo donax L.) were investigated. Because water-soluble extractives...     

Genetic aspects of age dynamics of a natural Picea abies (L.) Karst. population in the Białowieża Primeval Forest, Poland

We studied temporal changes in the genetic structure and diversity of a naturally regenerated Picea abies (L.) Karst. (Norway spruce) population in the Bia?owie?a Primeval Forest, Poland. The analysis included five age classes of trees: newly germinating seedlings (in laboratory conditions), seedlings up to 3 years old, young trees 4–10 years old, middle-aged trees 11–100 years old, and trees older than 100 years. We conducted genetic analyses of 26 allozyme loci using dormant buds from 405 individuals and 100 embryos. The results showed that the naturally regenerating Norway spruce population is genetically heterogeneous across the studied age classes. As determined by Chi squared tests, there were statistically significant differences in frequencies of alleles and genotypes as well as Wright’s index values (F) among the five age classes. The level of genetic differentiation (pairwise F_ST = 0.5–2.3 %) among the age class groups was equal to levels previously determined for various populations of this species. The Ewens-Watterson test for neutrality showed that one or two loci across different age classes of Norway spruce were affected by the selection process. The distinctiveness of embryo and seedling classes was confirmed by the number of detected alleles, the number of private alleles, the level of observed heterozygosity, and Wright’s index value. The results obtained in the present study indicate there are interesting dynamics of adaptation processes occurring in the natural age-diverse population of Norway spruce in the Bia?owie?a Primeval Forest.     

Integrated pest control in forest management — Combined use of pheromones and insecticides for attracting and killing the Bark Beetle Ips typographus I. Studies with 32P-labelled methamidophos in the ascending sap of spruce

In 1984–1986, ³²P-labelled methamidophos was used to investigate the translocation, distribution and breakdown of this systemic insecticide after penetration into the ascending sap of spruce (Picea abies Karst.), following bark treatment with an adhesive paste of 15% active ingredient. The β-radiation of ³²P permits a semi-quantitative measurement on the bark of standing trees as well as quantitative sample analysis and autoradiography. The following results are given: method of application and total ³²P in the ascending sap; distribution of ³²P in trunk cross-sections and in bark/needles; ³²P in the killed beetles corresponding to the toxic dose, separation of methamidophos and breakdown products; halflife of breakdown in vitro and in vivo; and environmental implications. From the xylem, methamidophos penetrates into the phloem, but no ³²P appears outside on the surface of the bark, so that only insects mining inside the bark are killed and no hazards for useful insects, birds and wildlife animals can arise. Traces of ³²P were measured in air and water, and no ³²P was found in the soil due to the translocation upwards only. The approximate oral toxicity of methamidophos to Ips typographus was estimated to be < 5 mg/kg and the half-life in spruce was 45 days (15°C), indicating a sufficient biological effectiveness over several months, preferably in areas of low average temperatures and in trees impaired by environmental pollution.     

Distribution of the timber quality attribute ‘knot surface’ in logs of Fagus sylvatica L. from pure and mixed forest stands

European Journal of Forest Research - Research on mixed forests has mostly focused on tree growth and productivity, or resistance and resilience in changing climate conditions, but only rarely on...     

Effects of different culture media on the growth of Indian sandalwood （Santalum album L.） seedlings in Zhanjiang, Guangdong, southern China

We studied the effects of different culture media on the growth of India sandalwood(Santalum album L.) seedlings in Zhanjiang,Guangdong Province in southern China. Five different growth substrates,lateritic subsoil,burnt soil,agricultural soil,peaty soil and coconut dust,were used as the basic culture materials and seven different treatments of composition were used as potting media. Kuhnia rosmarinifolia Vent. was used as a primary host plant for all treatments. Statistically significant differences were f...     

Introduction of Mandshurian ash (Fraxinus mandshurica Rupr.) to Estonia: Is it related to the current epidemic on European ash (F. excelsior L.)?

Recent investigations in Japan have suggested that the causal organism of the ongoing epidemic affecting European ash (Fraxinus excelsior) in Europe, Hymenoscyphus pseudoalbidus, may originate in East Asia. The fungus may have been unintentionally carried to Europe during the introduction of Mandshurian ash (F. mandshurica), the host tree of the fungus in East Asia. Still unicentric emergence hypothesis is in force: An area in the eastern Poland or Baltic has been shown to be the presumed epicentre of the epidemic. Really, during the Soviet occupation, several consignments of F. mandshurica seeds and plants, originating directly from the natural range of F. mandshurica in East Asia (Russian Far East), reached Baltic areas. In this paper, an overview about the Mandshurian ash is presented, the history of introduction of F. mandshurica to Estonia is reviewed and colonization of F. excelsior in this country by H. pseudoalbidus is briefly discussed. At present, we could not find any evidence, spatial or temporal, for a direct connection of the disease emergence on native F. excelsior with the introduction of F. mandshurica. The pathogen first colonized northwest Estonia and moved southeast and not from south to north as would be expected according to the hitherto existing unicentric hypothesis. However, more information is needed from different regions before to pose a multicentric emergence hypothesis and to deepen more into the investigations of the environmental factors that affected the host and supported to the epidemic in different areas.     

Changes induced by osmotic stress in the morphology,biochemistry, physiology,anatomy and stomatal parameters of almond species （Prunus L. spp.） grown in vitro

We investigated the influence of different levels of osmotic stress on growth and development in selected wild almond species(eight Prunus spp.) grown in vitro. The study, while endorsing the efficacy of in vitro screening of auxiliary buds of wild almond for osmotic stress tolerance, showed species variability in its response to osmotic stress. Osmotic stress reduced growth and development of all the species. However, the putative tolerant Prunus spp. showed better performance than the putative susceptible genotypes. On average there was an 80% decrease in shoot dry weight at-1.2 MPa. Reduction in shoot weight was more common in osmotic stress-susceptible species in the section labeled ‘Euamygdalus'. The tolerant Prunus species produced smaller changes in biochemical responses than the sensitive cultivars for malondialdehyde content, catalase activity, relative permeability of protoplast membranes, and net photosynthetic rate. The tolerant species maintained cell integrity better than drought sensitive species. Wild almond species in the section labeled ‘Spartioides'(Prunus arabica(Olivier) Neikle, Prunus glauca (Browicz) A.E. Murray, Prunus scoparia Spach) and ‘Lycioides'(Prunus lycioides Spach, Prunus reuteri Bossi. et Bushe) were best adapted to osmotic stress. Increase in chlorophyll concentration and leaf thickness under high osmotic stress can be considered as preliminary selection parameters for osmotic stress tolerance in Prunus spp. The study confirmed the efficacy of the in vitro method for screening of large number of genotypes for osmotic stress tolerance in wild almond species.     

Alley cropping in the moist savanna of West-Africa: I. Restoration and maintenance of soil fertility on ’terre de barre‘ soils in Bénin Republic

The potential of alley cropping systems supplied with a limited amount of fertilizer to restore crop productivity on a degraded site and to maintain crop productivity on a recently cleared, non-degraded site on ‘terre de barre‘ soils in Southern Bénin was investigated from 1994 to 1996. Leucaena leucocephala, Senna siamea and Gliricidia sepium were used as hedgerow species. Maize yields of the no-tree control plots dropped from the initial (1990) 401 kg ha−1 and 2181 kg ha−1 on the degraded and non-degraded sites, respectively, to 109 kg ha−1 and 1346 kg ha−1 in 1996, even with application of a minimal amount of mineral fertilizer. The alley cropping systems produced on average (mean of three treatments and three years) 107% more grain than the initial 1990 values on the degraded site and 11% less grain than the initial 1990 values on the non-degraded site. Especially the Senna and to a lesser degree the Leucaena treatment yielded consistently more grain than the control. The Senna trees contained a larger amount of N and produced more wood during the first pruning on the degraded site (155 kg N ha−1 and 14.0 ton fresh wood ha−1) than on the non-degraded site (49 kg N ha−1 and 6.6 ton fresh wood ha−1) most likely because of differences in subsoil fertility, as indicated by the higher clay, exchangeable bases, and N content between 60 and 125 cm cm. N accumulation and wood production by the Leucaena and Gliricidia trees was similar in both sites (82 and 36 kg N ha−1 and 4.6 and 9.3 ton fresh wood ha−1, respectively). When a limited amount of fertilizer is available, Senna appears to be the best choice as hedgerow species on sites with a relatively fertile subsoil. For other soils, a N2-fixing species may be a better choice. This revised version was published online in June 2006 with corrections to the Cover Date. This revised version was published online in June 2006 with corrections to the Cover Date.     

The influence of silane coupling agent and poplar particles on the wet-tability,surface roughness,and hardness of UF-bonded wheat straw （Triticum aestivum L.）/poplar wood particleboard

We used silane coupling agents to improve the bonding ability between wheat straw particles and UF resin, and investigated surface properties （wettability and surface roughness） and hardness of parti-cleboard made from UF-bonded wheat straw （Triticum aestivum L.） combined with poplar wood as affected by silane coupling agent content and straw/poplar wood particle ratios. We manufactured one-layered particleboard panels at four different ratios of straw to poplar wood par-ticles （0%, 15%, 30% and 45% wheat straw） and silane coupling agent content at three levels of 0, 5% and 10%. Roughness measurements, average roughness （Ra）, mean peak-to-valley height （Rz）, and root mean square roughness （Rq） were measured on unsanded samples by using a fine stylus tracing technique. We obtained contact angle measurements by using a goniometer connected to a digital camera and computer sys-tem. Boards containing greater amounts of poplar particles had superior hardness compared to control samples and had lower wettability. Panels made with higher amounts of silane had lower Rq values.