Showing papers by "Forest Research Institute published in 1989"

Processes Controlling Understorey Evapotranspiration

Abstract: The understorey often accounts for a significant proportion of forest evapotranspiration. In this paper we discuss the role of the understorey radiation regime, and the aerodynamic and stomatal conductance characteristics of the understorey in understorey evapotranspiration. Values of the McNaughton-Jarvis parameter 12 for the understorey in two mid-rotation Douglas-fir stands indicate considerable coupling between the understorey and the atmosphere above the overstorey. However, the stronger coupling between the oveistorey and the atmosphere accounts for the observation that the fraction of stand evapotranspiration originating at the understorey increases as the water vapour pressure deficit increases and the soil dries. We also discuss the approaches to describing the process of evaporation from the forest floor and the results of understorey removal experiments. These show small decreases in stand evapotranspiration and root-zone soil water content, but significant increases in the transpiration and growth of the trees.

Haemodynamic and hormonal responses to heat exposure in a Finnish sauna bath

Abstract: Eight healthy young men were studied during three periods of heat exposure in a Finnish sauna bath: at 80 degrees C dry bulb (80 D) and 100 degrees C dry bulb (100 D) temperatures until subjective discomfort, and in 80 degrees C dry heat, becoming humid (80 DH) until subjective exhaustion. Oral temperature increased 1.1 degrees C at 80 D, 1.9 degrees C at 100 D and 3.2 degrees C at 80 DH. Heart rate increased about 60% at 80 D, 90% at 100 D and 130% at 80 DH. Plasma noradrenaline increased about 100% at 80 D, 160% at 100 D and 310% at 80 DH. Adrenaline did not change. Plasma prolactin increased 2-fold at 80 D, 7-fold at 100 D and 10-fold at 80 DH. Blood concentrations of the beta-endorphin immunoreactivity at 100 D, adrenocorticotropic hormone (ACTH) at 100 D and 80 DH, growth hormone at 100 D and testosterone at 80 DH also increased, but cortisol at 80 D and 100 D decreased. The plasma prostaglandin E2 and serum thromboxane B2 levels did not change. Patterns related to heat exposure were observed for heart rate, plasma noradrenaline, ACTH and prolactin in the three study periods.

Steam Explosion of the Softwood Pinus Radiata with Sulphur Dioxide Addition. II. Process Characterisation

Abstract: The enzymatic digestibility of the softwood Pinus radiata is substantially enhanced by SO2-catalysed steam explosion. The factors controlling the effectiveness of this pretreatment have been studied. Under conditions of constant time (3 minutes) and temperature (215°c) the effects of SO2-impregnation levels from 0–11.8% were examined. Up to about 3% SO2 there is a pronounced effect on the enzymatic digestibility of the pretreated substrate and a rapid increase in the yield of water soluble sugars. At 2.55% SO2, a total sugar yield of 57.4 g/100 g oven-dry wood was obtained. SO2 levels above 3% had no beneficial effects in terms of increased sugar yields. Equivalent total sugar yields could be obtained by shortening the treatment time to 1 minute and increasing the temperature to 235°c (still at 2.55% SO2). Percentage solubilisation of wood glucan correlates strongly with the enzymatic digestibility of the pretreated substrate and also with the surface area accessible to a 51A molecule. This sugge...

The recent Ips typographus outbreak in Norway ‐ experiences from a control program

Abstract: During the period 1971-81 there were severe outbreaks of the bark beetle Ips typographus in southern Norway that damaged trees equivalent to 5 million cubic metres of timber. The outbreaks were caused partly by an extensive windblow and partly by drought. Trap trees were used until 1979, when pheromone-baited traps were introducted as part of an extensive control program. The various aspects of this program are outlined and problems of scientific, technological, economical-administrative and informative character are discussed. Possible explanation for the decline of the epidemic after 1980 is presented and the main conditions which must be fulfilled for achieving successful mass trapping of insect pests are listed.

Phenotypic changes in progenies of northern clones of Picea abies (L) Karst. grown in a southern seed orchard

Abstract: Results are presented from artificial freezing tests comparing young controlled crossed progenies from the southern seed orchard at Lyngdal (58° N) with open‐pollinated progenies from the same mother trees standing in the northern natural forest (63°‐66°N). The seed orchard material was more damaged by frost during cold acclimation. This effect was persistent for more than one growing season. Different photoperiodic treatments imposed on the progenies the first year did not affect the hardiness level in the same material three years later. The results imply that the seed orchard material has been genetically altered to perform like more southern ecotypes than the progenies form the forest. Possible causes of the present results are discussed in relation to four alternative hypotheses. In two of these it is postulated that the parental environment in the seed orchard could alter the genotypic performance of the progenies.

Genetic polymorphism of the apolipoprotein B gene locus influences serum LDL cholesterol level in familial hypercholesterolemia

Abstract: An XbaI restriction fragment length polymorphism (RFLP) within the coding region of the apolipoprotein B (apoB) gene has been found to be associated with serum cholesterol and triglyceride levels in several populations. Mutations in another genetic locus, the low density lipoprotein (LDL) receptor gene, give rise to familial hypercholesterolemia (FH), a disease characterized by hypercholesterolemia, tendon xanthmas and atherosclerosis. We determined the XbaI genotypes and serum lipoprotein levels of 120 unrelated patients with the heterozygous form of FH. A non-parametric analysis of variance showed a significant association between elevated serum total cholesterol concentration (P<0.05), serum LDL-choleterol concentration (P<0.025) and the presence of the XbaI restriction site (X2 allele). Thus, patients homozygous for the presence of the XbaI restriction site (genotype X2X2, n=28) had on average a 14% higher serum total cholesterol level and a 21% higher serum LDL-cholesterol level than those homozygous for the absence of this site (genotype X1X1, n=29); patients heterozygous for the XbaI restriction site (genotype X1X2, n=63) had intermediate serum total and LDL-cholesterol levels. No significant differences were seen in serum triglyceride or high-density lipoprotein (HDL)-cholesterol values between these patient groups. These data demonstrate that genetic polymorphism of the principal ligand for the LDL receptor, apoB, may contribute to serum cholesterol regulation, even in patients with grossly distorted cholesterol homeostasis.

The nature of the lower North Island floristic gap

Abstract: Patterns of regional endemism and disjunction of higher plants in the lower North Island are reviewed in relation to the plants' habitats. A redefinition of the lower North Island floristic gap emerges. A northern boundary in the southern central North Island uplands replaces the previous one at 39°S latitude. Southern boundaries occur either in Cook Strait or in southern Wellington-southern Wairarapa. Most endemic and disjunct species defining the gap occur in non-forest habitats. Previous explanations for these distribution patterns centre either on the disruptive effects of glacial ice and harsh climates of the Last Glaciation or on the tectonic modification of the New Zealand land mass since the Oligocene. It is suggested that regional discontinuities in the availability of non-forest habitats account for many disjunctions. Furthermore, patterns of endemism and disjunction most closely equate with the tectonic alteration of lower North Island. In particular, fault displacement of large land m...

Impacts of wetland afforestation on the distribution of benthic invertebrates in acid streams of Westland, New Zealand

Abstract: Inter‐relationships between some physical and chemical parameters of streams, the degree of catchment development, and benthic invertebrate distributions were investigated on two dates at 26 running‐water sites in North Westland, New Zealand. Streams draining catchments recently developed for forestry had higher summer water temperatures, greater total reactive aluminium concentrations (up to 31°C and 911 mg m‐3, respectively), and lower pH (down to 4.1) than most streams draining undeveloped wetland or native‐forested catchments. Apparent differences in water chemistry were attributed to the most recent development being at the heads of wetland catchments where leaching of organic acids into drainage waters was probably highest, rather than to any effects of development per se. Overall, streams that were very acidic (pH mostly 4.5 and drained native‐forested catchme...

Identification of the sex pheromone of three Matsucoccus pine bast scales

Abstract: Matsucoccus resinosae in the United States,M. matsumurae in China, andM. thunbergianae in Korea use (2E, 4E)-4,6,10,12-tetramethyl-2,4-tridecadien-7-one (1) (matsuone) as the primary component of their sex attractant pheromones. The structure was postulated from mass and NMR spectra and confirmed by synthesis of analogs3, (2E,4E)-4,6,11,12-tetramethyl-2,4-tridecadien-7-one, and4, (2E,4Z)-4,6,11,12-tetramethyl-2,4-tridecadien-7-one. Both analogs were attractive to the males ofM. resinosae in laboratory bioassays and toM. matsumurae in laboratory and field tests, but the 4Z analog (4) was much less so than the 4E analog (3) and had inhibitory effects at high concentrations. Dodecanol, isolated from aeration and solvent extracts of femaleM. resinosae, evoked characteristic wing-raising by pedestrian males, but the role of this response was not determined.

Naturally occurring Fusarium toxins in New Zealand maize

Abstract: Twenty samples of maize collected from healthy growing crops and at harvest time and during storage were screened for four Fusarium toxins (deoxynivalenol, diacetoxyscirpenol, T‐2 toxin and zearalenone) by gas chromatography‐mass spectrometry and thin‐layer chromatography. Seventeen samples (85%) contained one or more of these toxins. Zearalenone was present in 15 samples at levels ranging between 0.1 and 16 ppm. Deoxynivalenol, diacetoxyscirpenol and T‐2 toxin were found in 11, 6 and 13 samples respectively, all at levels below 1 ppm. This work documents the first reported natural occurrence of Fusarium toxins in New Zealand maize, and it is concluded that all four of the mycotoxins studied are prevalent in apparently healthy standing crops as well as in stored maize.

Distribution of root biomass in a low‐shrub pine bog

Abstract: The average stump and below‐ground biomass of pine was 1464 g/m2; 4% as fine roots (O 10 mm), and 29% stumps), which comprised 35% of the total biomass in the Scots pine stands. The average root length of pine was 728 m/m2: 71 % of this length was fine roots, 29% was small roots, and less than 1 % was large roots. Most of the fine pine roots (80%) were in the 0–10 cm peat layer. The root biomass of the field layer was 548 g/m2, which comprised 47 % of the total field layer biomass. Characteristic features of the root systems were: high below‐ground/above‐ground ratios, rather low amounts of root biomass, shallow rooting, and relatively thin roots. Hummocks tended to have less roots in the 0–10 cm layer and more roots in the 10–20 cm layer than the hollows.

Freeze‐testing young Picea abies plants

Abstract: Data from three independent experiments with young plants of Norway spruce were used in a methodological study of freezing tests. Frost hardiness was induced both in a phytotron and in a nursery. It was found that frost hardiness developed quickly in both environments; the frost damage decreased from 4–7% per day at a given test temperature. A large between‐ and within‐room variation in frost hardiness was obtained in the phytotron. Needle damage assessment data showed a large deviation from the normal distribution. A transformation of the data providing both normalization and homogenization of variances was possible. The plants were phenotypically grouped in different needle damage classes and mean values of growth and bud‐set were calculated for each of the classes. Mean plant height before tests and bud‐set were both strongly correlated to needle damage. Severely damaged plants were tallest, but the plants became tall because of late bud‐set. Severe needle damage had a negative influence on the growth ...

The effect of low- and high-density lipoprotein cholesterol on steroid hormone production and ACTH-induced differentiation of rat adrenocortical cells in primary culture

Abstract: We studied the effects of lipoprotein-derived cholesterol on the ACTH-induced differentiation of cultured fetal rat adrenocortical cells. For this purpose human plasma high-density lipoprotein3 (HDL3) or low-density lipoprotein (LDL) was added to culture media devoid of cholesterol, and thereafter the morphological changes in cells were monitored and the amounts of steroids synthesized were measured. It could be demonstrated that, ultrastructurally, upon ACTH-stimulation the adrenocortical cells differentiated into fasciculata-like cells even in the absence of lipoproteins in the culture medium. The addition of either HDL3 or LDL caused an increase in the number and size of cytoplasmic lipid droplets suggesting uptake and deposition of lipoprotein-derived cholesterol into the differentiating cells. The amount of steroids secreted from cells differentiating in media devoid of cholesterol was only half that observed in cells differentiating in serum-supplemented medium. Addition of either HDL3 or LDL increased the ACTH-stimulated steroid synthesis to the levels observed in serum-supplemented medium. This study demonstrates that both HDL3 and LDL are able to provide cholesterol for steroid synthesis accompanying the ACTH-induced differentiation of fetal rat adrenocortical cells.

Interspecific variation in defense secretions of Malaysian termites from the genusNasutitermes (Isoptera, nasutitermitinae)

Abstract: The defense secretions of five species of MalaysianNasutitermes,N. longinasus, N. matangensis, N, havilandi, N. johoricus, andNasutitermes species 01, are compared.N. longinasus andN. species 01 provide trinervitene alcohols,N. havilandi mainly tricyclic trinervitene and tetracyclic kempane alcohols and acetates, whereasN. matangensis furnish acetyl/propionyl derivatives of trinervita-11(12),15(17)-dien-3α,9β,13α-triol (XXI and XXII). A new diterpene, assigned as trinervita-11(12),15(17)-dien-3α,13α-diol-3,13-O-diacetate (XVII), is isolated fromN. havilandi. The mono- and diterpenoid compositions, being species-specific, are useful for chemotaxonomic and phylogenetic studies.

Colonization of southern beech byPlatypus caviceps (Coleoptera: Platypodidae).

Abstract: The role of host- and beetle-produced odors in the colonization of southern beech (Nothofagus spp.) by the pinhole borerPlatypus caviceps Broun was investigated. Host-selecting males attacked the crown zone of a recently felled tree. Beetle emergence and dispersal were influenced by temperature, and sparse colonization continued over the 30 days of the study. Field tests using naturally baited traps indicated that male colonization of southern beech can be accounted for by attraction to host odors alone and that subsequent female response is to a male-released sex pheromone acting alone or in combination with host odors.

Age structure and sex ratio in population of harvested feral pigs in New Zealand

Abstract: Data on age structures and sex ratios were collected from feral pig, Sus scrofa Linnaeus, 1758, populations in the northern part of the South Island, New Zealand. The age of 1966 pigs was assessed from (a) tooth replacement and wear (b) cementum layering in molars. The age structure of the feral pig population studied is typical of heavily utilized populations.

Annual patterns in reproduction and perirenal fat of hares (Lepus europaeus) in sub‐alpine Canterbury, New Zealand

Abstract: The aim of this paper was to describe how the age, sex and reproductive state of hares affected the amount of fat found around their left kidney. A total of 2208 hares (Lepus europaeus) was shot and autopsied over 13 years from sub-alpine grasslands in Canterbury, South Island, New Zealand. Adult females may be pregnant from July to mid-March. Adult males' testis weights were highest from July to January, and some fertile males may have been present in all months but April. The amount of perirenal fat in adults increased in autumn, peaked in early winter, and decreased thereafter to low levels through spring and summer. Autumn fat deposition in males was not clearly related to reproductive state in individuals, although it coincided with seasonal testicular development. Autumn fat deposition in females may have been caused in part by the cessation of lactation, but, like that in males, the increase was also part of an endogenous pattern. Fat utilization in winter was related to breeding. In males, utilization coincided with reproductive activity and the amount of perirenal fat remained consistently low throughout the breeding season. In females, net fat utilization was associated with lactation but this was balanced to some extent by fat deposition induced by pregnancy. Females simultaneously lactating and pregnant were in finer balance between utilization and deposition. Other factors, such as the number of embryos and the stage of gestation, altered the fat balance in these hares. Fat was also deposited as a ‘yolk-sac’ in embryos.

Evaluation of three techniques used to determine surfactant phytotoxicity

Abstract: Summary Three techniques were used to measure and compare the phytotoxicities of Triton X-45 and Agral 90 (two organic surfactants) with two organosilicone surfactants (Silwet L-77 and L-7607), and to compare these four non-ionic compounds with a cationic tallow amine surfactant (Hyspray). Total ion efflux and ethylene response methods were used in vivo and in vitro, while a betacyanin efflux method was an in vitro system only. The first two methods, using intact leaves, were considered to be more closely related to normal spraying conditions than the betacyanin efflux test which used explant material. However, the use of intact leaves was thought to bias the results in favour of the leaf penetration properties of the surfactants rather than their phytotoxicities. The in vitro pigment efflux method provided a simple way of ranking the surfactants in order of their potential phytotoxicities, especially with regard to effects on membrane permeability. This ranking, in increasing order of toxicity, was: Silwet L-7607, Silwet L-77, Agral 90, Triton X-45 and Hyspray.

Multiple hunting by lynx and red fox and utilization of prey by some carnivores

Abstract: Three observations on multiple hunting are reported and analysed. Wild lynx Lynx lynx Linnaeus, 1758 killed 3 roe deer Capreolus capreolus (Linnaeus, 1758) and hurt another one during one night in the forest enclosure. The lynx carefully covered the quarries with grass, litter and dirt and was returning to feed on the cache during 5 consecutive nights. Tamed female red fox Vulpes vulpes Linnaeus, 1758 rearing young was observed during a multiple hunt in a farmyard when it killed 5 domestic hens and negligently buried them in sand. The same vixen was observed when it got into the hen house and hurt 5 hens during 1-min hunt. In the first and the second case the predators tried to obtain and secure as much food as the favourable conditions would allow. The multiple hunting was undertaken after the evaluation of promising situation. The third case was the classic example of so-called "hen house syndrome". Therefore, multiple hunting and surplus killing by carnivores cannot be regarded the incidental and instinctive response to superabundant, vulnerable prey which then is not consumed but mainly wasted. Multiple hunting is often an adaptive behaviour, and is undertaken by a predator after the evaluation of a chance to acquire much food at low expense. Surplus food may be valuable or even critical during reproduction period of predator or in unfavourable conditions. Observation on polecat Mustela putorius Linnaeus, 1758 showed that the access to superabundant food ensured 14-day maintenance of a predator in winter.