Intra-annual changes in seagrass standing crop, Green Island, Northern Queensland

1993 ◽  
Vol 44 (1) ◽  
pp. 33 ◽  
Author(s):  
JE Mellors ◽  
H Marsh ◽  
RG Coles
Keyword(s):  
Standing Crop ◽  
Climatic Factors ◽  
Standing Stock ◽  
Light Availability ◽  
Principal Component ◽  
Dry Weight ◽  
Day Length ◽  
Strong Wind ◽  
Indirect Measures ◽  
Green Island

A visual estimation technique was used to estimate the standing crop of a mixed-species seagrass meadow at Green Island, northern Queensland. This technique measured monthly changes in the standing crop of seagrass within 10 fixed quadrats along three fixed transects from May 1987 to April 1988. The mean standing crop fluctuated by a factor of two from 60 g dry weight (DW) m-2 (August 1987) to 133 g DW m-2 (December 1987). The climatic factors that correlated with mean monthly standing crop were investigated. Owing to the high degree of association between these factors, principal-components analysis was used to create new orthogonal variables to be included in an 'all- subsets regression'. The best regression model explained only 12% of the variation in seagrass standing crop. This model and the magnitude and direction of the loadings of the vectors associated with the first principal component suggested that seagrass standing crop was positively correlated with any day length and temperature and negatively correlated with number of strong-wind days. These variables were indirect measures of light availability and temperature, suggesting that fluctuations in seagrass standing stock at Green Island were influenced by changes in temperature and light availability.

Structural changes in a Hieracium floribundum (Compositae) population associated with the process of patch formation

1978 ◽  
Vol 56 (1) ◽  
pp. 1-9 ◽  
Author(s):  
R. J. Reader
Keyword(s):  
Standing Crop ◽  
Structural Changes ◽  
Vegetative Reproduction ◽  
Light Availability ◽  
Dry Weight ◽  
Genetic Change ◽  
Allocation Pattern ◽  
Southern Ontario ◽  
Reproductive Structures ◽  
Allocation Patterns

The contribution of yellow devil hawkweed (H. floribundum) to the total standing crop of an abandoned pasture in southern Ontario increased from approximately 8% to 70% as H. floribundum colonized the pasture by forming patches containing as many as 3400 rosettes/m2. Within the hawkweed population, there was a significant (P < 0.05) shift in the distribution of standing crop from reproductive to vegetative structures and within the vegetative structures from leaves to roots and rhizome during the process of patch formation. These shifts presumably occurred in response to changing environmental conditions (i.e., increasing light availability, reduced soil moisture levels, greater intraspecific competition). The mechanism by which the allocation pattern changed was more likely phenotypic plasticity than genetic change since H. floribundum is an apomict and vegetative reproduction accounted for most recruitment into the population.The frequency distribution of population members in dry weight classes became more negatively skewed during the process of patch formation, but the distribution did not approach log-normality as predicted in some studies. Significant (P < 0.05) differences were observed in the allocation patterns of individuals belonging to different weight classes in the population. Only the largest plants in the population allocated dry weight to reproductive structures.

scholarly journals Radial Growth Response of European Larch Provenances to Interannual Climate Variation in Poland

Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 334
Author(s):  
Norbert Szymański ◽  
Sławomir Wilczyński
Keyword(s):  
Radial Growth ◽  
Climatic Factors ◽  
Principal Component ◽  
Climatic Conditions ◽  
Growth Responses ◽  
European Larch ◽  
Temperature And Precipitation ◽  
Provenance Trials ◽  
High Precipitation ◽  
Climatic Elements

The present study identified the similarities and differences in the radial growth responses of 20 provenances of 51-year-old European larch (Larix decidua Mill.) trees from Poland to the climatic conditions at three provenance trials situated in the Polish lowlands (Siemianice), uplands (Bliżyn) and mountains (Krynica). A chronology of radial growth indices was developed for each of 60 European larch populations, which highlighted the interannual variations in the climate-mediated radial growth of their trees. With the aid of principal component, correlation and multiple regression analysis, supra-regional climatic elements were identified to which all the larch provenances reacted similarly at all three provenance trials. They increased the radial growth in years with a short, warm and precipitation-rich winter; a cool and humid summer and when high precipitation in late autumn of the previous year was noted. Moreover, other climatic elements were identified to which two groups of the larch provenances reacted differently at each provenance trial. In the lowland climate, the provenances reacted differently to temperature in November to December of the previous year and July and to precipitation in September. In the upland climate, the provenances differed in growth sensitivity to precipitation in October of the previous year and June–September. In the mountain climate, the provenances responded differently to temperature and precipitation in September of the previous year and to precipitation in February, June and September of the year of tree ring formation. The results imply that both climatic factors and origin (genotype), i.e., the genetic factor, mediate the climate–growth relationships of larch provenances.

Relation of geographic variation in the skull of Microtus pennsylvanicus to climate

1983 ◽  
Vol 61 (6) ◽  
pp. 1232-1241 ◽  
Author(s):  
Richard R. Snell ◽  
Kimberly M. Cunnison
Keyword(s):  
Low Temperature ◽  
Geographic Variation ◽  
Multiple Regression ◽  
Minimum Spanning Tree ◽  
Climatic Factors ◽  
Principal Component ◽  
Microtus Pennsylvanicus ◽  
Annual Number ◽  
Simple Correlation ◽  
Morphometric Variation

Analyses of geographic variation in the skull of meadow voles (Microtus pennsylvanicus) indicate that phenetic distances among samples are not related to geographic distance: a minimum spanning tree based on average taxonomic distance superimposed on a map of 38 localities provides no particular phenetic clustering of those samples geographically proximate. A multiple regression of phenetic component one (skull size) onto orthogonally rotated climatic factors explains much less morphometric variation (25.6%) than a simple correlation with recorded extreme low temperature (38.9%). Multiple regression of phenetic principal component two (interorbital width) onto the same climatic factors explains minimally more morphological variation (42.1%) than a simple correlation with mean annual number of days with frost (41.7%). Microtus pennsylvanicus shows a pattern of size variation that is the reverse of Bergmann's rule: these voles are large where it is warm and small where it is cold. Since small size reduces total energy expenditure, we predict that during times of extreme low temperature (i) smaller voles will be less energetically stressed than larger voles and (ii) large size will be actively selected against.

scholarly journals Large scale laboratory cultures of Ankistrodesmus gracilis (Reisch) Korsikov (Chlorophyta) and Diaphanosoma biergei Korinek, 1981 (Cladocera)

2008 ◽  
Vol 68 (4) ◽  
pp. 875-883 ◽  
Author(s):  
LH. Sipaúba-Tavares ◽  
AML. Pereira
Keyword(s):  
Exponential Growth ◽  
Large Scale ◽  
Light Availability ◽  
Sharp Decrease ◽  
Dry Weight ◽  
Good Alternative ◽  
Production Costs ◽  
Determining Factors ◽  
Weight Protein ◽  
Low Costs

Large-scale lab culture of Ankistrodesmus gracilis and Diaphanososma birgei were evaluated by studying the biology and biochemical composition of the species and production costs. Ankistrodesmus gracilis presented exponential growth until the 6th day, with approximately 144 x 10(4) cells.mL-1, followed by a sharp decrease to 90 x 10(4) cells.mL-1 (8th day). Algae cells tended to increase again from the 11th day and reached a maximum of 135 x 10(4) cells.mL-1 on the 17th day. D. birgei culture showed exponential growth until the 9th day with 140 x 10² individuals.L-1, and increased again as from the 12th day. Algae A. gracilis and zooplankton D. birgei contain 47 to 70% dry weight protein and over 5% dry weight carbohydrates. The most expensive items in the context of variable costs were labor and electricity. Data suggested that temperature, nutrients, light availability and culture management were determining factors on productivity. Results indicate that NPK (20-5-20) may be used directly as a good alternative for mass cultivation when low costs are taken into account, promoting adequate growth and nutritional value for cultured A. gracilis and D. birgei.

scholarly journals The efficacy of different seed priming agents for promoting sorghum germination under salt stress

PLoS ONE ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. e0245505
Author(s):  
Xiaofei Chen ◽  
Ruidong Zhang ◽  
Yifan Xing ◽  
Bing Jiang ◽  
Bang Li ◽  
...  
Keyword(s):  
Salt Stress ◽  
Seed Germination ◽  
Germination Rate ◽  
Principal Component ◽  
Dry Weight ◽  
Seed Priming ◽  
Nacl Stress ◽  
Future Research ◽  
Fresh Weight ◽  
Positive Effects

Sorghum [Sorghum bicolor (L.) Moench] seed germination is sensitive to salinity, and seed priming is an effective method for alleviating the negative effects of salt stress on seed germination. However, few studies have compared the effects of different priming agents on sorghum germination under salt stress. In this study, we quantified the effects of priming with distilled water (HP), sodium chloride (NaCl), potassium chloride (KCl), calcium chloride (CaCl2), and polyethylene glycol (PEG) on sorghum seed germination under 150 mM NaCl stress. The germination potential, germination rate, germination index, vigor index, root length, shoot length, root fresh weight, shoot fresh weight, root dry weight, and shoot dry weight were significantly reduced by salt stress. Different priming treatments alleviated the germination inhibition caused by salt stress to varying degrees, and 50 mM CaCl2 was the most effective treatment. In addition, the mitigation effect of priming was stronger on root traits than on shoot traits. Mitigation efficacy was closely related to both the type of agent and the concentration of the solution. Principal component analysis showed that all concentrations of CaCl2 had higher scores and were clearly distinguished from other treatments based on their positive effects on all germination traits. The effects of the other agents varied with concentration. The priming treatments were divided into three categories based on their priming efficacy, and the 50, 100, and 150 mM CaCl2 treatments were placed in the first category. The 150 mM KCl, 10% PEG, HP, 150 mM NaCl, 30% PEG, and 50 mM KCl treatments were placed in the second category, and the 100 mM NaCl, 100 mM KCl, 20% PEG, and 50 mM NaCl treatments were least effective and were placed in the third category. Choosing appropriate priming agents and methods for future research and applications can ensure that crop seeds germinate healthily under saline conditions.

scholarly journals Influence of planning decisions on the local climate of residential building of the Krasnodar region and the Primorsk region

Vestnik MGSU ◽  
2019 ◽  
pp. 954-966 ◽  
Author(s):  
Bleil de Souza Clarice ◽  
Faridun F. Fayzullaev ◽  
Ilya V. Dunichkin
Keyword(s):  
Solar Radiation ◽  
Climatic Factors ◽  
Scientific Research ◽  
Residential Building ◽  
Theory Of Constraints ◽  
Published Data ◽  
Strong Wind ◽  
Wind Rose ◽  
Regulatory Documents ◽  
Terrain Features

Introduction: the article presents the examples of architectural and planning solutions on optimization of courtyard spaces in the southern regions of the Russian Federation, their protection from strong wind, insufficient airing, overheating and solar radiation, as well as anthropogenic and natural ones. In modern Russian construction, insufficient attention is paid to natural and climatic effects. Typical residential housing is used in all regions of the country. The main reason is the lack of regulatory documents for each region, which has its characteristics (presence of water bodies, terrain features, a wind rose, etc.). This problem dictates the need to structure the vital natural and climatic factors which affect the yard territory microclimate. Based on this, compensatory effective improvement methods and solutions that can balance the adverse effect of natural and climatic conditions and create the parameters and norms of architectural and urban planning design are presented. Materials and methods: the article analyzed the following information: standards, guidelines, design and regulatory documents in the field of construction and design, published data, and materials of domestic and foreign scientific research on this subject. Methods of scientific research are based on the use of factor and comparative analyses and the theory of constraints. Results: the article as formed the architectural and planning proposals on the residential area climate-based development. Conclusions: a planning structure based on local natural and climatic consideration (terrain features, the wind rose, etc.) and application of effective methods of territory protection from excessive solar radiation and adverse winds can form a favorable microclimate of a residential building for human comfort habitation. Correct assessment of the climatic features allows making bioclimatic protection economically sound and efficient in terms of energy consumption as well as defining favorable architectural and planning solutions.

scholarly journals Environmental factors affecting coffee (Coffea arabica L., Var. Castillo) quality in Colombia Southern

2020 ◽  
Vol 37 (2) ◽  
Author(s):  
Claudia Patricia Criollo-Velásquez ◽  
Johana Alixa Muñoz-Belalcazar ◽  
Tulio César Lagos-Burbano
Keyword(s):  
Climatic Factors ◽  
Principal Component ◽  
Average Score ◽  
Nutritional Factors ◽  
Factors Affecting ◽  
Thermal Amplitude ◽  
And Cluster Analysis ◽  
Soil Climate ◽  
Cup Quality

The determinant factors of coffee cup quality are highly variable and depend on their interaction with coffee production and benefit. This study aimed to analyze soil and climatic factors and their association with the cup quality of Castillo coffee variety of three to five years of age from production units in ecotypes 220A and 221A of the Department of Nariño. The study farms were located in three different altitudinal ranges: ≤1500 m, between 1501 and 1700 m, and >1700 m. Soil, climate, and coffee cup quality variables were analyzed through principal component analysis and cluster analysis. A low level of association was found between climatic and soil nutritional factors and coffee cup quality. Soil Mn, Fe, and Cu contents showed the highest association levels with cup quality, indicated by an average score of 80.89. The highest values of photosynthetically active radiation -PAR- and thermal amplitude were found in La Unión - Nariño, and these variables were associated with the group that obtained the highest cup quality score (82.58). Cup quality was not associated with elevation since the highest scores (85.5 and 82.33) were obtained from production units located at ≤1500 m.a.s.l. and >1700 m.a.s.l, respectively.

Flavonoids and Phenolic Acids in Methanolic Extracts, Infusions and Tinctures from Commercial Samples of Lemon Balm

2015 ◽  
Vol 10 (6) ◽  
pp. 1934578X1501000 ◽  
Author(s):  
Agnieszka Arceusz ◽  
Marek Wesolowski ◽  
Beata Ulewicz-Magulska
Keyword(s):  
Phenolic Compounds ◽  
Phenolic Acids ◽  
Principal Component ◽  
Hierarchical Cluster ◽  
Dry Weight ◽  
Melissa Officinalis ◽  
Lemon Balm ◽  
Biochemical Pathways ◽  
Methanolic Extracts ◽  
Principal Component Analyses

The aim of this study was to quantify the levels of flavonoids (rutin, myricetin, quercetin, kaempferol) and phenolic acids (gallic, p-coumaric, rosmarinic, syringic, caffeic, chlorogenic, ellagic, ferulic) in lemon balm ( Melissa officinalis L.) commonly used as a culinary, aromatic and medicinal herb. A rapid and reliable HPLC procedure was developed to determine the phenolic compounds in methanolic extracts, infusions and tinctures prepared from lemon balm. Except for myricetin and quercetin, as well as ellagic, gallic and rosmarinic acids, higher levels of the analytes under study were determined in the methanolic extracts (up to 22 mg/g of dry weight, DW), than in infusions (up to 5 mg/g DW). Tinctures were the poorest in flavonoids and phenolic acids (below 550 μg/g DW), except for ellagic and rosmarinic acids, which were quantified in tinctures at higher levels (mg/g DW). To sum up, the flavonoids were extracted more effectively in the infusions and tinctures than the phenolic acids. Statistically significant correlations were found between phenolic acids, possibly owing to similar biochemical pathways of the compounds. The hierarchical cluster and principal component analyses have also shown that the samples of lemon balm could be differentiated based on the levels of flavonoids and phenolic acids.

scholarly journals Evaluation of Two Parts of Lithocarpus polystachyus Rehd. from Different Chinese Areas by Multicomponent Content Determination and Pattern Recognition

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Min Wei ◽  
Yangling Tuo ◽  
Ye Zhang ◽  
Qi Deng ◽  
Cuiying Shi ◽  
...  
Keyword(s):  
Evaluation System ◽  
High Performance ◽  
Comprehensive Evaluation ◽  
Principal Component ◽  
Dry Weight ◽  
Quantification Analysis ◽  
Development And Utilization ◽  
Array Detection ◽  
Accurate Quantification

The purpose of this work is to establish a new method using high-performance liquid chromatography-diode array detection (HPLC-DAD) with chemometrics analysis to determine the content of catechin, isoquercetin, astragalin, phloridzin, trilobatin, and phloretin for one flavanol and five flavonoids, filter out the key compounds, and evaluate the quality of 26 batches of tender leaves and flower spikes of Lithocarpus polystachyus Rehd. (LP) from ten areas in China. The result showed that the HPLC-DAD method had excellent performance for accurate quantification analysis. S3 (tender leaf from Lushan, Sichuan) had the highest contents for six measured chemicals with trilobatin content of up to 27.82% in dry weight. S22 (flower spike from Liangping, Chongqing) had the highest content of phloridzin (up to 7.28%). All samples were divided into three types based on spatial distribution using principal component analysis. The result showed that the tender leaves and flower spikes from the same areas had many similar properties, and there were significant differences between the samples from different regions. Furthermore, phloridzin and trilobatin were identified as chemical markers for quality evaluation of two parts with different tender leaves and flower spikes of LP from geographical areas by orthogonal partial least squares discrimination analysis. These results will be helpful to establish an effective and comprehensive evaluation system of the development and utilization of LP resources.

Lichen Products of Cladonia Stellaris and C. Rangiferina Maintained Under Artificial Conditions

1981 ◽  
Vol 13 (1) ◽  
pp. 87-91 ◽  
Author(s):  
Dianne Fahselt
Keyword(s):  
Light Intensity ◽  
Light Availability ◽  
Usnic Acid ◽  
Dry Weight ◽  
Lichen Thallus

AbstractLichen thallus fragments were maintained in a growth cabinet under four differing conditions of light intensity. Levels of usnic acid and atranorin did not differ significantly from the control under any of the treatments. However, perlatolic acid and fumarprotocetraric acid per unit dry weight of thallus were dependent upon light availability.

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