scholarly journals Long-term standardized forest phenology in Sweden: a climate change indicator

2019 ◽  
Author(s):  
Ola Langvall ◽  
Mikaell Ottosson Löfvenius
Keyword(s):  
Climate Change ◽  
Quantitative Methods ◽  
Food Resource ◽  
Growth Period ◽  
Phase Changes ◽  
Gradual Change ◽  
Active Growth ◽  
Statistical Precision ◽  
Active Growth Period

Abstract Because climate change alters patterns of vegetative growth, long-term phenological measurements and observations can provide important data for analyzing its impact. Phenological assessments are usually made as records of calendar dates when specific phase changes occur. Such assessments have benefits and are used in Citizen Science monitoring. However, these kinds of data often have low statistical precision when describing gradual changes. Frequent monitoring of the phenological traits of forest trees and berries as they undergo gradual change is needed to acquire good temporal resolution of transitions relative to other factors, such as susceptibility to frosts, insects, and fungi, and the use of berries as a food resource. Intensive weekly monitoring of the growth of apical and branch buds and the elongation of shoots and leaves on four tree species, and the abundance of flowers and berries of bilberry and lingonberry, has been performed in Sweden since 2006. Here, we present quantitative methods for interpolating such data, which detail the gradual changes between assessments in order to describe average rates of development and amount of interannual variation. Our analysis has shown the active growth period of trees to differ with latitude. We also observed a change in the timing of the maximum numbers of ripening berries and their successive decline. Data from tree phenology assessments can be used to recommend best forestry practice and to model tree growth, while berry data can be used to estimate when food resources for animals are most available.

scholarly journals Rainy springs linked to poor nestling growth in a declining avian aerial insectivore ( Tachycineta bicolor )

2019 ◽  
Vol 286 (1898) ◽  
pp. 20190018 ◽  
Author(s):  
Amelia R. Cox ◽  
Raleigh J. Robertson ◽  
Ádám Z. Lendvai ◽  
Kennedy Everitt ◽  
Frances Bonier
Keyword(s):  
Climate Change ◽  
Body Mass ◽  
Food Availability ◽  
Food Resource ◽  
Food Abundance ◽  
Tachycineta Bicolor ◽  
Long Term Study ◽  
Flying Insects ◽  
Food Shortages

As species shift their ranges and phenology to cope with climate change, many are left without a ready supply of their preferred food source during critical life stages. Food shortages are often assumed to be driven by reduced total food abundance, but here we propose that climate change may cause short-term food shortages for foraging specialists without affecting overall food availability. We frame this hypothesis around the special case of birds that forage on flying insects for whom effects mediated by their shared food resource have been proposed to cause avian aerial insectivores' decline worldwide. Flying insects are inactive during cold, wet or windy conditions, effectively reducing food availability to zero even if insect abundance remains otherwise unchanged. Using long-term monitoring data from a declining population of tree swallows ( Tachycineta bicolor ), we show that nestlings’ body mass declined substantially from 1977 to 2017. In 2017, nestlings had lower body mass if it rained during the preceding 3 days, though females increased provisioning rates, potentially in an attempt to compensate. Adult body mass, particularly that of the males, has also declined over the long-term study. Mean rainfall during the nestling period has increased by 9.3 ± 0.3 mm decade −1 , potentially explaining declining nestling body mass and population declines. Therefore, we suggest that reduced food availability, distinct from food abundance, may be an important and previously overlooked consequence of climate change, which could be affecting populations of species that specialize on foraging on flying insects.

THE STUDY OF CLIMATE EFFECTS ON THE NUT YIELD OF COCONUT USING PARSIMONIOUS MODELS

1998 ◽  
Vol 34 (2) ◽  
pp. 189-206 ◽  
Author(s):  
T. S. G. PEIRIS ◽  
R. O. THATTIL
Keyword(s):  
Sunshine Duration ◽  
Growth Period ◽  
Climate Data ◽  
Active Growth ◽  
Dry Matter Partitioning ◽  
Air Temperatures ◽  
Nut Production ◽  
Parsimonious Models ◽  
June July ◽  
Active Growth Period

The coconut yield is harvested in six picks per year at two-monthly intervals. The yield variation between and within years is very complex and this variability has not yet been explained. The analysis of long-term nut yield and monthly climate data: rainfall (RF), pan evaporation (EV), sunshine duration (SS), wind velocity (WV), minimum and maximum air temperatures (TMIN and TMAX), and relative humidity in forenoons and afternoons (RHAM and RHPM), using multivariate methods enabled the use of the variables TMAX, RHPM and EV as significantly important determinants (parsimonious set of variables) to represent the effects of climate on coconut irrespective of picks. Parsimonious models developed using these three variables explain how the development of bunches during the active growth period responded to climate variables without physiological parameters. The models are desirable where interpretation is concerned. The yields of picks one to six were determined by the climate variability during February, June, July, September, December and February respectively. Based on the models the proper timing of the use of some agronomic practices to enhance the productivity was recommended. A common model was also fitted (R2 = 0.81; p < 0.002) to estimate the annual yield 18 months in advance using EV, RHPM and TMAX. The three variables influence the microclimate around the crown of the palm for utilizing solar radiation in dry matter partitioning and thereby nut production. The method used to screen climatic variables so as to develop parsimonious crop–weather models using multivariate and univariate techniques can be used for other tree crops.

Nitrogenase activity associated with Zostera marina from a North Carolina estuary

1982 ◽  
Vol 28 (4) ◽  
pp. 448-451 ◽  
Author(s):  
Garriet W. Smith ◽  
Steven S. Hayasaka
Keyword(s):  
North Carolina ◽  
Zostera Marina ◽  
Nitrogenase Activity ◽  
Growth Period ◽  
Winter Period ◽  
Late Winter ◽  
Active Growth ◽  
North Carolina Estuary ◽  
Active Growth Period

Nitrogenase activity (at in situ temperatures) associated with Zostera marina reflected the active growth periods of this plant in North Carolina coastal waters. During the plants most active growth period (late winter – spring) nitrogenase activity was primarily rhizospheric (8.47 μmol nitrogen fixed∙m−2∙day−1), while during its fall – early winter period it was primarily phyllospheric (8.03 μmol nitrogen fixed∙m−2∙day−1). No nitrogenase activity was detected during the warmer summer months when the plant is dormant. Phyllospheric nitrogenase activity (possibly the result of epiphytic heterocystic blue-green bacteria) was highest when plants were incubated aerobically in the presence of light.

Availability of nitrogen after fertilizer applications to cereals

2001 ◽  
Vol 136 (2) ◽  
pp. 141-157 ◽  
Author(s):  
J. A. KING ◽  
R. SYLVESTER-BRADLEY ◽  
A. D. H. ROCHFORD
Keyword(s):  
Growth Period ◽  
N Recovery ◽  
Fertilizer N ◽  
Soil Mineral ◽  
Soil Mineral Nitrogen ◽  
Active Growth ◽  
Soil Microbial ◽  
Winter Cereals ◽  
Crop Uptake ◽  
Active Growth Period

An experiment was conducted over seven sites in eastern England sown to winter cereals, whereby the soil mineral nitrogen (N) and N recovery in the crop were measured frequently during the active growth period. Plots received 100 kg/ha fertilizer N on one of three dates in spring (28 March, 11 April and 25 April) on each site in each of the three years (1994 to 1996), and these were compared with controls with no applied N. At one site, uncropped plots were included, and measurements of gaseous N emission, soil respiration, soil microbial biomass and root tissue N concentration were also made. The fertilizer applications boosted yields by at least 3 t/ha at all sites, but apparent recovery of fertilizer N varied throughout the previously known range of 45–85%. Soil type and timing of application had no effect on N recovery, or on final yields. N was mineralized from soil sources throughout the growth period, but mineralization was outweighed by ‘‘immobilization’’ of large amounts of N (around 30 kg/ha) in the soil, chiefly during May when crop growth was most rapid. This occurred on all sites with a crop, but not where the crop was absent. Measured losses of N2 and N2O were very small (<70 g/ha/dayN) on the site where they were measured, and no other evidence of loss or storage of N was found. The apparent recovery of fertilizer N at each site, was almost exactly explained by the amount immobilized during May. We conclude that the poor recovery of spring-applied N was due, not to losses as previously assumed but to temporary immobilization during the period of most active crop uptake. Immobilization was caused primarily by the presence of the crop.

EXTRACELLULAR POLYSACCHARIDES OF SERRATIA MARCESCENS

1964 ◽  
Vol 42 (10) ◽  
pp. 1403-1413 ◽  
Author(s):  
G. A. Adams ◽  
S. M. Martin
Keyword(s):  
Serratia Marcescens ◽  
Culture Filtrate ◽  
Glucuronic Acid ◽  
Carbon Sources ◽  
Growth Period ◽  
The Other ◽  
Extracellular Polysaccharides ◽  
Active Growth ◽  
Electrophoretic Behavior ◽  
Active Growth Period

Growth of Serratia marcescens on sucrose, D-glucose, D-galactose, and D-xylose as carbon sources did not affect the composition of the extracellular polysaccharides significantly. D-Glucose was the major component with lesser amounts of D-mannose, heptose, L-fucose, and L-rhamnose. Rhamnose did not appear until near the end of the active growth period and increased proportionately more than the other sugars thereafter. From the culture filtrate after 20 hours growth on sucrose, two acidic polysaccharides were isolated. They were markedly different in composition and electrophoretic behavior although both contained glucose as their major component. One was characterized by a relatively high content of rhamnose and heptose, the other by the presence of mannose; both contained glucuronic acid. Other impure polysaccharides were isolated from the culture filtrate. It seems likely that S. marcescens produced a spectrum of rather similar extracellular polysaccharides of which the two isolated ones comprise the main types.

scholarly journals Propagation of a Novel Cytoplasmic, Infectious and Deleterious Determinant Is Controlled by Translational Accuracy in Podospora anserina

Genetics ◽  
1999 ◽  
Vol 151 (1) ◽  
pp. 87-95 ◽  
Author(s):  
Philippe Silar ◽  
Vicki Haedens ◽  
Michèle Rossignol ◽  
Hervé Lalucque
Keyword(s):  
Mitochondrial Dna ◽  
Stationary Phase ◽  
Biological Significance ◽  
Growth Period ◽  
Podospora Anserina ◽  
Active Growth ◽  
Translational Accuracy ◽  
Active Growth Period ◽  
Factor C ◽  
Sexual Crosses

AbstractSome mutant strains of the filamentous fungus Podospora anserina spontaneously present a growth impairment, which has been called Crippled Growth (CG). CG is caused by a cytoplasmic and infectious factor, C. C is efficiently transmitted during mitosis but is not transmitted to the progeny after sexual crosses. C is induced by stationary phase and cured by various means, most of which stress the cells. Translational accuracy is shown to tightly regulate the propagation of C during the active growth period, because its propagation in dividing hyphae is restricted to cells that display an increased translational accuracy. However, induction of C in stationary phase proceeds independently from the translational accuracy status of the strain. CG does not seem to be accompanied by mitochondrial DNA modifications, although C activates the action of the Determinant of Senescence, another cytoplasmic and infectious element, which causes a disorganization of the mitochondrial genome. In addition, presence of C drastically modifies the spectrum of the mitochondrial DNA rearrangements in AS6-5 mat–cultures during Senescence. C seems to belong to the growing list of unconventional genetic elements. The biological significance of such elements is discussed.

scholarly journals Morphological Variations of Nutrient Foramina in Upper Limb Long Bones

2013 ◽  
Vol 2 (2) ◽  
pp. 177
Author(s):  
M. Sharma ◽  
R. Prashar ◽  
T. Sharma ◽  
A. Wadhwa
Keyword(s):  
Upper Limb ◽  
Growth Period ◽  
Long Bone ◽  
Long Bones ◽  
Active Growth ◽  
Morphological Variations ◽  
Nutrient Foramen ◽  
Nutrient Artery ◽  
Nutrient Foramina ◽  
Active Growth Period

The nutrient artery is the principal source of blood supply to a long bone and is particularly important during its active growth period in the embryo and foetus as well as during the early phase of ossification. The aim of the present study was to study the topographic anatomy and morphology of the nutrient foramina in human adult upper limb long bones. The study was performed on 40 upper limb long bones which include 40 humerii, 40 radii, 40 ulnae. The bones were obtained from department of anatomy Punjab institute of medical sciences, Jalandhar. The variations were found in number and location of nutrient foramen in different upper limb bones. In humerus double and triple foramina were found. In radius and ulna double foramina were observed at the maximum. Absence of nutrient foramen was observed in radius. The knowledge about these foramina is useful in surgical procedures.

INFLUENCE OF CYSTEINE ON THE PRODUCTION OF HAEMOTOXIN OF CL. WELCHII

1934 ◽  
Vol 11 (5) ◽  
pp. 622-627
Author(s):  
J. H. Orr ◽  
G. B. Reed
Keyword(s):  
Reduction Potential ◽  
Marked Effect ◽  
Growth Period ◽  
Fish Muscle ◽  
Direct Reaction ◽  
Active Growth ◽  
Oxidation Reduction ◽  
Oxidation Reduction Potential ◽  
Active Growth Period ◽  
Beef Muscle

It has been shown that the addition of 0.1% or more of cysteine to Robertson's chopped meat media completely inhibits the production of haemotoxin by Cl. welchii and that H2S has a similar effect. The effect is shown to be related to the metabolism of the organisms and not to a direct reaction with the formed toxin. The addition of these concentrations of cysteine was shown to have little effect upon the oxidation-reduction potential of sterile media but a marked effect upon the oxidation-reduction potential of cultures during the most active growth period. Beef muscle media low in cystine were shown to give a good yield and fish muscle relatively high in cystine was shown to give a poor yield of haemotoxin.

scholarly journals Deoxynivalenol (DON) Accumulation and Nutrient Recovery in Black Soldier Fly Larvae (Hermetia illucens) Fed Wheat Infected with Fusarium spp.

Fermentation ◽  
2019 ◽  
Vol 5 (3) ◽  
pp. 83 ◽  
Author(s):  
Zehra Gulsunoglu ◽  
Smitha Aravind ◽  
Yuchen Bai ◽  
Lipu Wang ◽  
H. Randy Kutcher ◽  
...  
Keyword(s):  
Pupal Stage ◽  
Growth Period ◽  
Economic Loss ◽  
Kernel Weight ◽  
Head Blight ◽  
Active Growth ◽  
Black Soldier Fly ◽  
Black Soldier Fly Larvae ◽  
Fly Larvae ◽  
Active Growth Period

Fusarium head blight (FHB) is one of the most significant causes of economic loss in cereal crops, resulting in a loss of $50–300 million for Canadian agriculture. The infected grain (containing Fusarium-damaged kernels (FDKs)) is often both lower in quality and kernel weight, and it may be unsuitable for human and animal consumption due to mycotoxin presence. However, it still contains a considerable amount of nutrients. A method to recover the nutrients without the mycotoxins should be beneficial for the agricultural economy. In this study, our objective was to examine recovery methods of the nutrients in relation to mycotoxin accumulation in the insect. The FDKs were fermented with Aspergillus oryzae and/or Lactobacillus plantarum (solid-state fermentation (SSF)). The SSF kernels were then provided to 50 young, black soldier fly larvae (BSFL) for 12 days. Weight gain, chemical composition, and mycotoxin bioaccumulation of BSFL and spent feed were evaluated. After 12 days of insect culture, the BSFL grew 5–6 times their initial weight. While the overall weights did not significantly vary, the proteins and lipids accumulated more in SSF FDK-fed insects. During the active growth period, the larval biomass contained deoxynivalenol (DON), a mycotoxin, at detectable levels; however, by day 12, when the larvae were in the pre-pupal stage, the amount of DON in the insect biomass was nearly negligible, i.e., BSFL did not accumulate DON. Thus, we conclude that the combination of BSFL and SSF can be employed to recover DON-free nutrients from FHB-infected grain to recover value from unmarketable grain.

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