Pollen̵1Pistil Interactions in Eucalyptus calophylla Provide No Evidence of a Selection Mechanism for Aluminium Tolerance

1993 ◽  
Vol 41 (5) ◽  
pp. 541 ◽  
Author(s):  
LM Egerton-Warbuton ◽  
BJ Griffin ◽  
BB Lamont
Keyword(s):  
Pollen Tube ◽  
Soil Ph ◽  
Aluminium Tolerance ◽  
Forest Site ◽  
Al Tolerance ◽  
Mine Site ◽  
Reproductive Tissues ◽  
Forest Sites ◽  
Significant Difference ◽  
Selection For

Selection for aluminium (Al) tolerance was assessed by studying pollen-pistil interactions in Eucalyptus calophylla trees colonising a 30-year-old abandoned coal mine-site (soil pH 4.3) compared with E. calophylla trees on an adjacent forest-site (soil pH 5.3). Energy-dispersive X-ray micro-analysis of reproductive tissues demonstrated that low levels of Al occurred in the stigma, lower style and unfertilised ovules of forest-site flowers. In contrast, significantly higher levels of Al were detected in all reproductive tissues of mine-site flowers. Al concentrations were higher at the base of the style than in the stigma. Al was also detected in stigmatic exudates of mine-site flowers. Selection for Al tolerance occurred in the anther of mine-site flowers as pollen from mine-site flowers germinated six-fold (15.6%) compared with forest-site pollen (2.6%) at the highest concentration of Al (22 ppm) used. However, the rate of pollen tube growth was not significantly different between mine- and forest-sites at any Al concentration. Tolerance of Al by the mine-site pollen was not shared by the progeny as there was no increase in the survival or growth of mine-site seedlings in mine soils over forest-site seedlings. Controlled pollinations between mine-/forest-site pollen and mine-site pistils demonstrated that there was no significant difference in the number of mine- or forest-site pollen tubes at any level in the style in mine-site pistils. Pollen tube abnormalities principally occurred in mine-site pistils. We concluded that there is no evidence yet for a genetically-based tolerance of Al in E. calophylla on coal mining soils.

scholarly journals The composition and diversity of natural regeneration of tree species in gaps under different intensities of forest disturbance

2021 ◽  
Author(s):  
Maame Esi Hammond ◽  
Radek Pokorný ◽  
Daniel Okae-Anti ◽  
Augustine Gyedu ◽  
Irene Otwuwa Obeng
Keyword(s):  
Tree Species ◽  
Natural Regeneration ◽  
Forest Disturbance ◽  
Forest Site ◽  
Gap Formation ◽  
Tree Species Composition ◽  
Forest Sites ◽  
Significant Difference ◽  
Shade Tolerant Species ◽  
Disturbed Forest

AbstractThe positive ecological interaction between gap formation and natural regeneration has been examined but little research has been carried out on the effects of gaps on natural regeneration in forests under different intensities of disturbance. This study evaluates the composition, diversity, regeneration density and abundance of natural regeneration of tree species in gaps in undisturbed, intermittently disturbed, and disturbed forest sites. Bia Tano Forest Reserve in Ghana was the study area and three gaps each were selected in the three forest site categories. Ten circular subsampling areas of 1 m2 were delineated at 2 m spacing along north, south, east, and west transects within individual gaps. Data on natural regeneration < 350 cm height were gathered. The results show that the intensity of disturbance was disproportional to gap size. Species diversity differed significantly between undisturbed and disturbed sites and, also between intermittently disturbed and disturbed sites for Simpson’s (1-D), Equitability (J), and Berger–Parker (B–P) indices. However, there was no significant difference among forest sites for Shannon diversity (H) and Margalef richness (MI) indices. Tree species composition on the sites differed. Regeneration density on the disturbed site was significantly higher than on the two other sites. Greater abundance and density of shade-dependent species on all sites identified them as opportunistic replacements of gap-dependent pioneers. Pioneer species giving way to shade tolerant species is a natural process, thus make them worst variant in gap regeneration.

Reserves of aluminium and mineral nutrients in seeds ofEucalyptus calophylla(Myrtaceae) with reference to the globoid inclusions

1995 ◽  
Vol 5 (1) ◽  
pp. 53-57
Author(s):  
Louise M. Egerton-Warburton ◽  
Brendon J. Griffin ◽  
John Kuo
Keyword(s):  
Soil Ph ◽  
Forest Soils ◽  
Coal Mine ◽  
Mineral Nutrients ◽  
Soil Conditions ◽  
Forest Site ◽  
Parent Plant ◽  
Mine Site ◽  
X Ray ◽  
Germinating Seeds

AbstractAmounts of mineral nutrients and aluminium (Al) were assessed in the globoid inclusions, proteinaceous matrix and druse crystals ofEucalyptus calophyllaseeds collected from trees grown in coal-mine (mean soil pH 4.3, Al 260 μg g−1) and forest soils (pH 5.3, Al 10 μg g−1). Energy-dispersive X-ray microanalysis (EDX) of bulk frozen hydrated samples indicated that significantly higher amounts of Mg, P, S, K and Ca occurred in the globoid inclusions of mine- than forest-site seeds. In both seedstocks, Al was detected in the globoid inclusions but not in the proteinaceous matrix or druse crystals. Significantly higher amounts of Al occurred in mine-site samples of dry and germinating seeds than in forest-site seeds. It was concluded that globoid inclusions may be useful as indicators of the soil conditions in which the parent plant was grown.

Differential responses of Pisolithus tinctorius isolates to aluminum in vitro

1995 ◽  
Vol 73 (8) ◽  
pp. 1229-1233 ◽  
Author(s):  
Louise M. Egerton-Warburton ◽  
Brendon J. Griffin
Keyword(s):  
Mycelial Growth ◽  
Axenic Culture ◽  
Pisolithus Tinctorius ◽  
Energy Dispersive ◽  
Forest Site ◽  
Al Tolerance ◽  
Mine Site ◽  
X Ray ◽  
Physiological Tolerance

Isolates of Pisolithus tinctorius collected from old coal mining (pH 4.3, Al 327 mg/L, mine sites), rehabilitated (pH 4.9, Al 22 mg/L), and forest sites (pH 5.3, Al 6 mg/L) were grown in axenic culture with 0–2000 mg/L Al and assessed for aluminum tolerance by comparing the mass of mycelia produced and levels of Al, Ca, and Mg in mycelia as detected by energy-dispersive X-ray microanalysis. Mine-site isolates demonstrated mycelial growth to 2000 mg/L Al, a threshold of 90 mg/L Al before accumulation of Al in mycelia, and higher levels of Ca and Mg within the mycelia than either rehabilitated- or forest-site isolates at substrate concentrations greater than 4 mg/L Al. In contrast, mycelial growth ceased at 22 and 12 mg/L Al for rehabilitated- and forest-site isolates, respectively, and was strongly correlated with a high Al and low Ca and Mg content in the mycelia. These differences indicated that an increase in Al tolerance of mine-site isolates may operate through an increase in the presence of Ca and Mg in mycelia and a physiological tolerance to the metal. Key words: Pisolithus tinctorius, Al, Ca, Mg, axenic culture, energy-dispersive X-ray microanalysis.

scholarly journals Effect of Mosses on physical and chemical properties of soil in temperate forests of Garhwal Himalayas

2021 ◽  
pp. 1-10
Author(s):  
Anshu Siwach ◽  
Siddhartha Kaushal ◽  
Ratul Baishya
Keyword(s):  
Physical Properties ◽  
Chemical Properties ◽  
Nutrient Status ◽  
High Rate ◽  
Physical And Chemical Properties ◽  
Garhwal Himalayas ◽  
Forest Sites ◽  
Significant Difference ◽  
Physical And Chemical ◽  
And Chemical Properties

Abstract Mosses are one of the most important and dominant plant communities, especially in the temperate biome, and play a significant role in ecosystem function and dynamics. They influence the water, energy and element cycle due to their unique ecology and physiology. The present study was undertaken in three different temperate forest sites in the Garhwal Himalayas, viz., Triyuginarayan (Kedarnath Wildlife Sanctuary (KWLS)), Chakrata, and Kanasar forest range. The study was focused on understanding the influence of mosses on soil physical properties and nutrient availability. Different physico-chemical properties were analysed under two different substrata, that is, with and without moss cover in two different seasons, viz., monsoon and winter. We observed mosses to influence and alter the physical properties and nutrient status of soil in both seasons. All soil physical and chemical properties, except magnesium, showed significant difference within the substrates, among all the sites and across the two seasons. Besides the soil characteristics underneath the moss vegetation, the study also highlights the diversity of mosses found in the area. Mosses appear to create high nutrient microsites via a high rate of organic matter accumulation and retain nutrients for longer periods thus, maintaining ecosystem stability.

Biological and chemical features of Poltava Meat breed pigs bacon depending on genotype

2021 ◽  
pp. 74-80
Author(s):  
N. Garskaya ◽  
L. Peretyatko
Keyword(s):  
Subcutaneous Tissue ◽  
Morphological Structure ◽  
Live Weight ◽  
Fatty Degeneration ◽  
Fat Cells ◽  
Breeding Lines ◽  
Meat Content ◽  
Group I ◽  
Significant Difference ◽  
Selection For

The research goal is to carry out comprehensive studies to define the biological and chemical characteristics of the young Poltava Meat Breed boars’ bacon for further work with existing genotypes and creating new ones.Materials and methods. The research was carried out on bacon samples taken from Poltava Meat Breed boars of different genotypes during the «control slaughter» at the age of reaching the live weight of 100 kg. Purebred Poltava Meat Breed boars were divided into two groups according to the principle of paired analogs: the group I (control) contained animals of «clean» breeding lines (16 heads), and the group II (experimental) contained animals with 12,5% of the Finnish Landrace blood (14 heads). The thickness of the bacon, its morphological structure and its chemical features were studied. All the results obtained were then processed by statistical methods.Results. It was found that Poltava Meat Breed boars, regardless of the genotype, had bacon thickness values below the Poltava Meat Breed target standard after reaching the live weight of 100 kg, with very low variability of the indicator (1,05–1,69%). However, there was no significant difference between the groups. During the morphological study of the samples, qualitative differences in the bacon of animals from different groups were noted. In the first group, the subcutaneous tissue (bacon) is subject to more pronounced destructive changes due to the intensified process of fatty degeneration. The fat cells of animals with Finnish Landrace blood were slightly smaller, but no significant difference between the area of fat cells in boars of different genotypes was found. The variability of morphological parameters in both groups was average (23,91% and 16,23%). The infusion of Finnish Landrace blood to the Poltava Meat Breed boars led to a change in the chemical composition of bacon, such as: an increase in the amount of moisture by 8,58% (p≤0,01), protein by 3,62% (p≤0,01), a decrease in the amount of fat by 9,25% (p≤0,01), to a decrease in the saponification number by 8,36% (p≤0,01) and the iodine number by 10,48% (p≤0,01).Conclusion. The bacon of Poltava Meat Breed boars is characterized by biological and chemical features due to both species and genotype. The established features of the bacon of Poltava Meat Breed boars indicate a significant decrease in its quality in the case of Finnish Landrace blood infusion. Intensive selection for meat content of Poltava Meat Breed pigs leads to a significant decrease in the thickness of the bacon and excessive selection pressure.

Evaluation of Snow Albedo in Land Models for Weather and Climate Studies

2010 ◽  
Vol 49 (3) ◽  
pp. 363-380 ◽  
Author(s):  
Zhuo Wang ◽  
Xubin Zeng
Keyword(s):  
Climate Models ◽  
Snow Water Equivalent ◽  
Weather Forecasting ◽  
Vegetation Type ◽  
Global Model ◽  
Forest Site ◽  
Snow Albedo ◽  
Community Land Model ◽  
In Situ Data ◽  
Forest Sites

Abstract Snow albedo plays an important role in land models for weather, climate, and hydrometeorological studies, but its treatment in various land models still contains significant deficiencies. Complementary to previous studies that evaluated the snow albedo as part of an overall land model study, the snow albedo formulations as used in four major weather forecasting and climate models [European Centre for Medium-Range Weather Forecasts (ECMWF), National Centers for Environmental Prediction (NCEP) “Noah” land model, National Center for Atmospheric Research (NCAR) Community Land Model (CLM3), and NCEP global model] were directly evaluated here using multiyear Boreal Ecosystem–Atmosphere Study (BOREAS) in situ data over grass and forest sites. First, four idealized cases over grass and forest sites were designed to understand better the different albedo formulations in these models. Then the BOREAS data were used to evaluate snow albedo and relevant formulations and to identify deficiencies of each model. Based on these analyses, suggestions that involve only minor changes in parameters or formulations were made to significantly reduce these deficiencies of each model. For the ECMWF land model, using the square root of snow water equivalent (SWE), rather than SWE itself, in the computation of snow fraction would significantly reduce the underestimation of albedo over grass. For the NCEP Noah land model, reducing (increasing) the critical SWE for full snow cover over short (tall) vegetation would reduce the underestimate (overestimate) of snow albedo over the grass (forest) site. For the NCAR CLM3, revising the coefficient used in the ground snow-fraction computation would substantially reduce the albedo underestimation over grass. For the albedo formulations in the NCEP global model, replacing the globally constant fresh snow albedo by the vegetation-type-dependent Moderate-Resolution Imaging Spectroradiometer (MODIS) maximum snow albedo would significantly improve the overestimation of model albedo over forest.

Ecology of cultivable yeasts in pristine forests in northern Patagonia (Argentina) influenced by different environmental factors

2014 ◽  
Vol 60 (6) ◽  
pp. 371-382 ◽  
Author(s):  
María Cecilia Mestre ◽  
Sonia Fontenla ◽  
Carlos A. Rosa
Keyword(s):  
Environmental Factors ◽  
Volcanic Activity ◽  
Forest Site ◽  
Nothofagus Pumilio ◽  
Species Accumulation Curves ◽  
Environmental Characteristics ◽  
Factors Affecting ◽  
Complex Interactions ◽  
Forest Sites ◽  
Nothofagus Antarctica

Environmental factors influencing the occurrence and community structure of soil yeasts in forests are not well studied. There are few studies dedicated to Southern Hemisphere soil yeasts populations and even fewer focused on temperate forests influenced by volcanic activity. The present work aimed to study the ecology of soil yeast communities from pristine forests influenced by different environmental factors (precipitation, physicochemical properties of soil, tree species, soil region, and season). The survey was performed in 4 northern Patagonian forests: 2 dominated by Nothofagus pumilio and 2 by Nothofagus antarctica. Yeast communities were described with ecological indices and species accumulation curves, and their association with environmental characteristics was assessed using multivariate analysis. Each forest site showed a particular arrangement of species as a result of environmental characteristics, such as dominant plant species, nutrient availability, and climatic characteristics. Cryptococcus podzolicus was most frequently isolated in nutrient-rich soils, Trichosporon porosum dominated cold mountain forests with low nutrient and water availability in soil, and capsulated yeasts such as Cryptococcus phenolicus dominated forest sites with low precipitation. The present work suggests that environmental factors affecting yeast communities may not be the current soil characteristics but the result of complex interactions of factors including natural disturbances like volcanic activity.

scholarly journals Stand Structure, Productivity and Carbon Sequestration Potential of Oak Dominated Forests in Kumaun Himalaya

2016 ◽  
Vol 11 (2) ◽  
pp. 466-476
Author(s):  
Bijendra Lal ◽  
L.S. Lodhiyal
Keyword(s):  
Carbon Sequestration ◽  
Primary Productivity ◽  
Tree Species ◽  
Stand Structure ◽  
Basal Area ◽  
Forest Site ◽  
Forest Sites ◽  
Sequestration Potential ◽  
Oak Tree ◽  
Quercus Leucotrichophora

Present study deals with stand structure, biomass, productivity and carbon sequestration in oak dominated forests mixed with other broad leaved tree species. The sites of studied forests were located in Nainital region between 29058’ N lat. and 79028’ E long at 1500-2150 m elevation. Tree density of forests ranged from 980-1100 ind.ha-1. Of this, oak trees shared 69-97%. The basal area of trees was 31.81 to 63.93 m2 ha-1. R. arboreum and Q. floribunda shared maximum basal area 16.45 and 16.32 m2 ha-1, respectively in forest site-1 and 2 while Quercus leucotrichophora shared maximum (35.69 m2 ha-1) in site-3. The biomass and primary productivity of tree species ranged from 481-569 t ha-1 and 16.9-20.9 t ha-1yr-1, respectively. Of this, biomass and primary productivity of oak tree species accounted for 81 to 95 and 78 to 98%, respectively. Carbon stock and carbon sequestration ranged from 228 to 270 t ha-1 and 8.0 to 9.9 t ha-1yr-1, respectively. The share of oak tree species ranged from 81 to 94.7 and 79 to 97%, respectively. The diversity of tree species ranged from 0.03 to 0.16 in forest sites-1, 2 and 3. The diversity of oak species was 0.08-0.16 in all the forest sites. Thus it is concluded that among the oak tree species, Quercus floribunda and Quercus leucotrichophora were highly dominated in the studied forests. The climax form of oak dominated trees in the studied forest sites depicted slightly lower richness and diversity of tree species compared to the forests in the region and elsewhere. As far as dry matter and carbon of forests is concerned, these estimates are close to the earlier reports of forests in the region. Therefore, studied forests have the potential to increase the diversity, productivity and carbon sequestration of forest tree species by providing the adequate scientific conservation and management inputs.

scholarly journals Intrabasin Floral Differences in the Sonoran Desert; a case study from the Casa Grande Valley

2014 ◽  
Author(s):  
Gabriela Garcia ◽  
Sarah Gabriele ◽  
Benjamin Cowgill ◽  
Xavier Rodriguez ◽  
Robert J Gay
Keyword(s):  
Community Composition ◽  
Soil Ph ◽  
Sonoran Desert ◽  
Mineral Content ◽  
Controlling Factors ◽  
Floral Variation ◽  
Significant Difference ◽  
Elevation Data ◽  
Expected Values

Background: The purpose of this study was to determine what floral differences exist in North Mountain Park and Casa Grande Mountain Park which are both located on opposite sides of the Casa Grande Valley, Pinal County, Arizona and to attempt to explain any measured differences. Previous authors have proposed several explanations for floral variation within the Sonoran Desert including elevation, soil pH, and mineral content. This study explicitly tests several of these proposed mechanisms for determining community composition. Methods: The floral composition was measured in both North Mountain Park and Casa Grande Mountain Park through a series of transects which were sampled by multiple times in 2012 and 2013. Elevation data soil pH were also sampled. Results: The data recovered from North Mountain Park differed from the expected values in Casa Grande Mountain Park by 22%. This indicates a significant difference in the flora between these two localities that was not predicted by earlier studies. Elevation and soil pH differences between sampled localities were not significant. This suggests that mineral composition of the soil may play an important role within this basin in determining community composition. Discussion: Many factors that have been proposed in prior studies do not appear to play a significant role within the Casa Grande Valley in determining community composition. This indicates that the composition of a community is influenced by different factors in different locations within the Sonoran Desert. This makes determining overall controlling factors across an ecosystem difficult.

scholarly journals Constraining ecosystem model with Adaptive Metropolis algorithm using boreal forest site eddy covariance measurements

2016 ◽  
Author(s):  
Jarmo Mäkelä ◽  
Jouni Susiluoto ◽  
Tiina Markkanen ◽  
Mika Aurela ◽  
Ivan Mammarella ◽  
...  
Keyword(s):  
Boreal Forest ◽  
Gross Primary Production ◽  
Co2 Concentration ◽  
Moisture Stress ◽  
Ecosystem Model ◽  
Metropolis Algorithm ◽  
Forest Site ◽  
Diurnal Cycles ◽  
Forest Sites ◽  
Eddy Covariance Measurements

Abstract. We examined parameter optimization in JSBACH ecosystem model, applied for two boreal forest sites in Finland. We identified and tested key parameters in soil hydrology and forest water and carbon exchange related formulations and optimized them using the Adaptive Metropolis algorithm for a five year calibration period (2000–2004) followed by a four year validation period (2005–2008). We were able to improve the modelled seasonal, daily and diurnal cycles of gross primary production and evapotranspiration but unable to enhance the models response to dryness. The improvements are mostly accounted for by parameters related to the ratio of leaf internal CO2 concentration to external CO2, relative humidity, transpiration and soil moisture stress.

Sign in / Sign up

Export Citation Format

Share Document