Structure and physiology of Sitka spruce roots

1987 ◽  
Vol 93 (1-2) ◽  
pp. 131-144 ◽  
Author(s):  
M. P. Coutts ◽  
J. J. Philipson
Keyword(s):  
Relative Size ◽  
Local Environment ◽  
Sitka Spruce ◽  
Lateral Spread ◽  
Soil Conditions ◽  
Soil Environment ◽  
Nitrogen And Phosphorus ◽  
Tree Stability ◽  
Primary Roots ◽  
Survival And Development

SynopsisThe growth and development of Sitka spruce roots is reviewed against the practical background of tree stability. Two features of the roots which make Sitka spruce liable to windthrow on upland sites are the shallow development in unfavourable soil conditions, and restricted lateral spread and anchorage caused by some forms of cultivation. Responses to different aspects of the soil environment are discussed, with emphasis on mineral nutrition, drying of the soil, waterlogging and temperature. The development of a small number of major woody roots from an assortment of primary laterals on the transplant occurs at an early age and is determined both by the relative size and vigour of the primary roots and by their local environment. The roots, which respond to increases in nitrogen and phosphorus supply with enhanced growth, are sensitive to drying of the soil and are particularly so to waterlogging, but they show no unusual response to soil temperature. Adventitious roots can play a role in the survival and development of the root system.

scholarly journals The Role of Biochar in Regulating the Carbon, Phosphorus, and Nitrogen Cycles Exemplified by Soil Systems

2021 ◽  
Vol 13 (10) ◽  
pp. 5612
Author(s):  
Shu-Yuan Pan ◽  
Cheng-Di Dong ◽  
Jenn-Feng Su ◽  
Po-Yen Wang ◽  
Chiu-Wen Chen ◽  
...  
Keyword(s):  
Environmental Sustainability ◽  
Soil Amendment ◽  
Environmental Control ◽  
Current Knowledge ◽  
Soil Environment ◽  
Nitrogen And Phosphorus ◽  
Soil Systems ◽  
P Mineralization ◽  
Rich Material ◽  
Pyrolysis Of Biomass

Biochar is a carbon-rich material prepared from the pyrolysis of biomass under various conditions. Recently, biochar drew great attention due to its promising potential in climate change mitigation, soil amendment, and environmental control. Obviously, biochar can be a beneficial soil amendment in several ways including preventing nutrients loss due to leaching, increasing N and P mineralization, and enabling the microbial mediation of N2O and CO2 emissions. However, there are also conflicting reports on biochar effects, such as water logging and weathering induced change of surface properties that ultimately affects microbial growth and soil fertility. Despite the voluminous reports on soil and biochar properties, few studies have systematically addressed the effects of biochar on the sequestration of carbon, nitrogen, and phosphorus in soils. Information on microbially-mediated transformation of carbon (C), nitrogen (N), and phosphorus (P) species in the soil environment remains relatively uncertain. A systematic documentation of how biochar influences the fate and transport of carbon, phosphorus, and nitrogen in soil is crucial to promoting biochar applications toward environmental sustainability. This report first provides an overview on the adsorption of carbon, phosphorus, and nitrogen species on biochar, particularly in soil systems. Then, the biochar-mediated transformation of organic species, and the transport of carbon, nitrogen, and phosphorus in soil systems are discussed. This review also reports on the weathering process of biochar and implications in the soil environment. Lastly, the current knowledge gaps and priority research directions for the biochar-amended systems in the future are assessed. This review focuses on literatures published in the past decade (2009–2021) on the adsorption, degradation, transport, weathering, and transformation of C, N, and P species in soil systems with respect to biochar applications.

scholarly journals A new terrestrial biosphere model with coupled carbon, nitrogen, and phosphorus cycles (QUINCY v1.0; revision 1772)

2019 ◽  
Author(s):  
Tea Thum ◽  
Silvia Caldararu ◽  
Jan Engel ◽  
Melanie Kern ◽  
Marleen Pallandt ◽  
...  
Keyword(s):  
Terrestrial Ecosystem ◽  
Terrestrial Ecosystems ◽  
Ecosystem Dynamics ◽  
Soil Conditions ◽  
Monitoring Networks ◽  
Nitrogen And Phosphorus ◽  
Element Cycling ◽  
Terrestrial Biosphere ◽  
Ecosystem Monitoring ◽  
Terrestrial Ecosystem Model

Abstract. The dynamics of terrestrial ecosystems are shaped by the coupled cycles of carbon, nitrogen and phosphorus, and strongly depend on the availability of water and energy. These interactions shape future terrestrial biosphere responses to global change. Many process-based models of the terrestrial biosphere have been gradually extended from considering carbon-water interactions to also including nitrogen, and later, phosphorus dynamics. This evolutionary model development has hindered full integration of these biogeochemical cycles and the feedbacks amongst them. Here we present a new terrestrial ecosystem model QUINCY (QUantifying Interactions between terrestrial Nutrient CYcles and the climate system), which is formulated around a consistent representation of element cycling in terrestrial ecosystems. This new model includes i) a representation of plant growth which separates source (e.g. photosynthesis) and sink (growth rate of individual tissues, constrained by nutrients, temperature, and water availability) processes; ii) the acclimation of many ecophysiological processes to meteorological conditions and/or nutrient availabilities; iii) an explicit representation of vertical soil processes to separate litter and soil organic matter dynamics; iv) a range of new diagnostics (leaf chlorophyll content; 13C, 14C, and 15N isotope tracers) to allow for a more in-depth model evaluation. We present the model structure and provide an assessment of its performance against a range of observations from global-scale ecosystem monitoring networks. We demonstrate that the framework is capable of consistently simulating ecosystem dynamics across a large gradient in climate and soil conditions, as well as across different plant functional types. To aid this understanding we provide an assessment of the model's sensitivity to its parameterisation and the associated uncertainty.

Evidence that tropical soil environment can support the growth of Escherichia coli

1998 ◽  
Vol 38 (12) ◽  
pp. 171-174 ◽  
Author(s):  
M. N Byappanahalli ◽  
R. S. Fujioka
Keyword(s):  
Escherichia Coli ◽  
Water Quality ◽  
Tropical Soil ◽  
Soil Conditions ◽  
Natural Soil ◽  
Minimal Amount ◽  
Soil Environment ◽  
Faecal Coliforms ◽  
E Coli ◽  
Faecal Bacteria

Concentrations of faecal coliforms and Escherichia coli in environmental waters have historically been used to establish recreational water quality standards. When these bacteria are used as indices of water quality, it is assumed that there are no significant environmental sources of these bacteria which are unrelated to direct faecal contamination. However, we have previously reported that in tropical island environments such as in Hawaii, these faecal indicators are consistently found at high concentrations in all streams and the source of these faecal bacteria is the soil. To become so well established in soil we hypothesized that these faecal bacteria must have the ability to multiply in the natural soil environment at ambient temperature (23–25°C). Three lines of evidence support this hypothesis: (1) E. coli was shown to grow on 10% soil extract agar, (2) populations of faecal coliforms and E. coli from sewage were shown to immediately increase by about three logs when simple nutrients (glucose and salts) were added to natural soil and (3) faecal coliforms and E. coli increased by two logs within 24 h when a minimal amount of sewage was added to cobalt-irradiated soil. These results indicate that tropical soil environments provide sufficient means to support the growth of faecal coliforms and E. coli. However, under natural soil conditions, indigenous soil microorganisms are much more efficient in obtaining nutrients and we hypothesize that faecal bacteria grow sporadically in response to available nutrients.

scholarly journals Root biomass of beech as a factor influencing the wind tree stability 

2019 ◽  
Vol 48 (No. 12) ◽  
pp. 549-564 ◽  
Author(s):  
J. Kodrík ◽  
M. Kodrík
Keyword(s):  
Root System ◽  
Groundwater Level ◽  
Negative Impact ◽  
Lateral Roots ◽  
Root Systems ◽  
Static Stability ◽  
Soil Conditions ◽  
Tree Stability ◽  
Ground Biomass ◽  
Below Ground

Beech is, thanks to its root system, in general considered to be a wind-resistant woody plant species. Nevertheless, the research on beech root systems has revealed that it is not possible to mechanically divide the woody plants into deep rooted and shallow rooted, because their root systems are modified according to various stand conditions. The root system shape, growth and development are mostly influenced by soil conditions and groundwater level. In the case of a high groundwater level beech root systems do not form tap roots and the lateral roots are rather thin and weak. Important factor for the tree static stability is number of roots with diameter 3–10 cm. The most important for the tree stability are roots with diameter over 10 cm. Wood-destroying fungi have strong negative impact on tree static stability. There are differences between beech below-ground biomass growing in soils rich in nutrients and poor in nutrients. The total below-ground biomass of the beech stands poor in nutrients is higher.

Sensing the physical and nutritional status of the root environment in the field: a review of progress and opportunities

2005 ◽  
Vol 143 (5) ◽  
pp. 347-358 ◽  
Author(s):  
L. J. CLARK ◽  
D. J. G. GOWING ◽  
R. M. LARK ◽  
P. B. LEEDS-HARRISON ◽  
A. J. MILLER ◽  
...  
Keyword(s):  
Nutritional Status ◽  
Crop Management ◽  
Soil Conditions ◽  
Plant Responses ◽  
Soil Environment ◽  
Soil Factors ◽  
Remote Sensors ◽  
Soil Measurements ◽  
New Strategies

The challenge that faces agriculture at the start of the 21st Century is to provide security of food production in a sustainable way. Achieving this task is difficult enough, but against a background of climate change, it becomes a moving target. However, one certainty is that soil factors that limit crop growth must be taken into account as new strategies for crop management are developed. To achieve this, it is necessary to measure the physical and nutritional status of the root environment in the field. Before considering measurement methods, our understanding of how the plant interacts with its soil environment is reviewed, so that it is clear what needs to be measured. Soil strength due to soil drying is identified as an important stress that limits agricultural productivity. The scope to measure soil factors that directly affect plant growth is reviewed. While in situ sensors are better developed, progress in the development of remote sensors of soil properties are also reviewed. A robust approach is needed to interpret soil measurements at the field scale and here geostatistics has much to offer. The present review takes a forward look and explores how our understanding of plant responses to soil conditions, the newly emerging sensing technologies and geostatistical tools can be drawn together to develop robust tools for soil and crop management. This is not intended to be an exhaustive review. Instead, the authors focus on those aspects that they consider to be most important and where the greatest progress is being made.

Some ecological aspects of Sitka spruce

1987 ◽  
Vol 93 (1-2) ◽  
pp. 85-92 ◽  
Author(s):  
D. C. Malcolm
Keyword(s):  
Sitka Spruce ◽  
Climatic Variables ◽  
Stand Dynamics ◽  
Soil Conditions ◽  
Atmospheric Humidity ◽  
Natural Distribution ◽  
Potential Production ◽  
Natural Stand ◽  
Ecological Aspects ◽  
Accumulated Temperature

SynopsisThe general adaptations of the species are described in relation to the environment of its natural distribution and are shown to be well suited to its use as an exotic in forestry. What is known of natural stand dynamics has little relevance to the cultivation of the species in pure plantations but the interaction with climate and soils is important in determining the limits to its growth and in prediction of productivity. Atmospheric humidity, windiness and accumulated temperature appear to be the most influential climatic variables and, given adequate soil conditions, can be used to give good estimates of potential production. Sitka spruce flowers freely and regenerates readily, demonstrating its ability to survive unaided in British conditions.

scholarly journals Development of an Infection Assay for Sporisorium reilianum, the Head Smut Pathogen on Sorghum

Plant Disease ◽  
1998 ◽  
Vol 82 (11) ◽  
pp. 1232-1236 ◽  
Author(s):  
Jairo A. Osorio ◽  
Richard A. Frederiksen
Keyword(s):  
Moisture Content ◽  
Culture Media ◽  
Soil Conditions ◽  
Soil Environment ◽  
Head Smut ◽  
Infection Efficiency ◽  
Maize Hybrid ◽  
Inoculation Technique ◽  
Corpus Christi ◽  
Sporisorium Reilianum

The practical value of dry teliospores of Sporisorium reilianum as inoculum in head smut infection assays was determined from a series of studies using three different isolates of the pathogen. Overall germinability of teliospores ranged from 8.0 to 28.0% on culture media after 48 h of incubation. Teliospores germinated at slower rates in the vicinity of sorghum seedlings growing on germination paper, reaching maximum values of 11.5 to 13.0% after 120 h. These results suggest adaptation in the germination strategy of S. reilianum, probably modulated by the variable soil environment. Fifteen percent (15%) of the seedlings of a head smut susceptible maize hybrid inoculated with teliospores of S. reilianum at root protrusion openings of the mesocotyl tissues became infected, while seedlings similarly inoculated with sporidial suspensions remained uninfected. Three sorghum lines susceptible to head smut were inoculated in three separate experiments with dry teliospores of isolates from Corpus Christi and Taylor, Texas. Seeds were imbibed for 18 h, and the seedlings were planted in soil at 40% moisture content (wt/wt) and covered with a 1:50 (vol/vol) mixture of teliospores and autoclaved soil. Infection levels obtained in these experiments were 2.5 to 2.8 times higher than field infection levels on susceptible lines RT×7078 and B1. In this study, average infection levels of 65 to 79.5% and 84 to 87% for RT×7078 and B1, respectively, were obtained with Corpus Christi isolates of S. reilianum; whereas Taylor isolates infected 91.9 and 82.3% of the plants in these two lines. It is postulated that the increased infection efficiency observed with this inoculation technique results from uniform and higher levels of inoculum, timely delivered under stable soil conditions that provide the pathogen with an environment more conducive for infection.

Windthrow hazard modelling in boreal forests of black spruce and jack pine

2005 ◽  
Vol 35 (11) ◽  
pp. 2655-2663 ◽  
Author(s):  
Jean-Gabriel Elie ◽  
Jean-Claude Ruel
Keyword(s):  
Boreal Forests ◽  
Pinus Banksiana ◽  
Forest Cover ◽  
Black Spruce ◽  
Jack Pine ◽  
Soil Conditions ◽  
Mechanical Resistance ◽  
Mixed Stands ◽  
Tree Stability ◽  
Tree Resistance

In this study we compare the mechanical resistance of black spruce (Picea mariana (Mill.) BSP) and jack pine (Pinus banksiana Lamb.) and quantify the effect of species, forest cover type, and soil conditions on tree stability. To measure tree resistance to an applied load, 85 trees were pulled over using a cable and winch system. Predictive equations for the maximum turning moment that a tree can withstand (Mc) were developed with stem mass, and the other factors were used as explanatory variables. The presence of jack pine within the stand negatively affected black spruce resistance. In mixed stands, Mc was significantly influenced by the interaction between tree species and soil type. Jack pine was the only species with significantly lower resistance when grown on shallow and stony soils, which are likely to restrict root development. Black spruce resistance was not affected by soil conditions. Preliminary calculations of critical wind speeds required to cause damage using an adaptation of the ForestGALES model were much lower than those previously published for black spruce.

scholarly journals Evaluating the risk of non-point source pollution from biosolids: integrated modelling of nutrient losses at field and catchment scales

2007 ◽  
Vol 11 (1) ◽  
pp. 601-613 ◽  
Author(s):  
P. G. Whitehead ◽  
A. L. Heathwaite ◽  
N. J. Flynn ◽  
A. J. Wade ◽  
P. F. Quinn
Keyword(s):  
Integrated Modelling ◽  
Distributed Model ◽  
Soil Conditions ◽  
Catchment Scale ◽  
Nitrogen And Phosphorus ◽  
Flow Paths ◽  
P Loss ◽  
Application Rates ◽  
Wide Range ◽  
Key Variables

Abstract. A semi-distributed model, INCA, has been developed to determine the fate and distribution of nutrients in terrestrial and aquatic systems. The model simulates nitrogen and phosphorus processes in soils, groundwaters and river systems and can be applied in a semi-distributed manner at a range of scales. In this study, the model has been applied at field to sub-catchment to whole catchment scale to evaluate the behaviour of biosolid-derived losses of P in agricultural systems. It is shown that process-based models such as INCA, applied at a wide range of scales, reproduce field and catchment behaviour satisfactorily. The INCA model can also be used to generate generic information for risk assessment. By adjusting three key variables: biosolid application rates, the hydrological connectivity of the catchment and the initial P-status of the soils within the model, a matrix of P loss rates can be generated to evaluate the behaviour of the model and, hence, of the catchment system. The results, which indicate the sensitivity of the catchment to flow paths, to application rates and to initial soil conditions, have been incorporated into a Nutrient Export Risk Matrix (NERM).

Sign in / Sign up

Export Citation Format

Share Document