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Role of Water in Plant System
Published in A. Zaman, Md. Hedayetullah, Sustainable Water Resource Development and Management, 2022
The plants absorb soil water and nutrients through root systems, that is, fibrous roots and taproots. Graminaceous or Poaceae family has monocotyledon and fibrous root systems. Monocot crops are rice, wheat, etc. Most of the dicotyledonous plants such as peas, lentils, sugar beets, and alfalfa, have taproot systems. Radical is the first root appearing from a seed, is a seminal root. The other part grows above the ground is plumule. From the primary root, secondary and lateral branches come. In maize plant, roots may also develop from above ground nodes such as the brace roots. Tap root penetrates much deeper as compared with the fibrous root system. The tap root having less root branch is compared with tap root system. The main aim of this type of root is to better anchorage. The monocotyledons and dicotyledons plants differ with clear root length and complex branching root system. The growth pattern of primary branch is more as compared with the secondary branch followed by the lateral roots. Root elongation is observed as high as 2.4 inches per day in maize. Under unfavorable conditions, root growth may severely be restricted.
Phytotechnologies for Site Remediation
Published in Larry E. Erickson, Valentina Pidlisnyuk, Phytotechnology with Biomass Production, 2021
Valentina Pidlisnyuk, Ganga M. Hettiarachchi, Zeljka Zgorelec, Melissa Prelac, Nikola Bilandžija, Lawrence C. Davis, Larry E. Erickson
Sida hermaphrodita L. Rusby (Virginia mallow) is a C4, honey plant species (Figure 2.5) which belongs to Malvaceae family (mallows); it originated in North America. During the 1930s the plant was introduced to former USSR, and currently it can be found in all parts of Europe. Virginia Mallow is tolerant to extreme types of continental climate and can survive in cold conditions (even without snow at temperatures below −20°C) and dry conditions if the average annual precipitation ranges between 400 and 500 mm. Height in full maturity varies from 1 to 4 m, commonly reaches about 3 m (Borkowska & Molas, 2012). Its life span is about 25 years (Kasprzyk et al., 2013), the annual yield ranges from 15 to 20 t of dry matter ha−1 when cultivated in clay loam soils (Borkowska, 2007). In case of unfavorable conditions, the cultivation is often provided with the addition of sewage sludge; in this condition yield ranges from none to 11 tons of dry matter ha−1 (Borkowska & Wardzinska, 2003). The well-developed root system allows it to efficiently use limited nutrients and water from marginal soils (Borkowska & Wardzinska, 2003). S. hermaphrodita grows well in stony or sandy soil with high yields, and best growth is reported for moderately humid areas. Hybrids and cultivars are mainly cultivated now because they have higher yields than the original species. The data about phytoremediation potential of Virginia mallow are summarized in Table 2.5.
Defects due to vegetation
Published in A. M. Sowden, The Maintenance of Brick and Stone Masonry Structures, 2020
Certain species of trees, particularly elms, poplars and willows, make high moisture demands on the subsoi) and thereby can affect foundations. Clay soils undergo considerable changes in volume with varying moisture content, shrinking as they dry out and expanding as water is absorbed. Therefore root systems which extend into such soils and remove water from the ground under a structure can cause settlement damage, which will be exacerbated by seasonal variations. The effect is most marked when foundations are shallow, as they frequently are for older structures. However, deeper foundations are not necessarily immune, as root penetration to considerable depths is possible and for mature trees drying influences can extend to a depth of 5 m or more. Conversely, the removal of established trees may reverse the process, allowing such soils to reabsorb moisture, swell and cause heave, which may continue for a decade or more with insidiously adverse effects on foundations. Autumn leaf fall may block surface drains at a critical time; root growth penetrating a buried drain at a joint or crack can readily develop to the stage where it forms an effective plug. Overmature, diseased or unstable trees may fall and damage nearby structures.
Phytoremediation of toxic chemicals in aquatic environment with special emphasis on duckweed mediated approaches
Published in International Journal of Phytoremediation, 2023
Aparupa Thakuria, Kundan Kumar Singh, Arup Dutta, Eduardo Corton, Devard Stom, Lepakshi Barbora, Pranab Goswami
Many critical findings have emerged in the recent past from the field of phytoremediation. Plants with a fast growth rate and high biomass production were shown to be more effective in removing Cd (Yang et al. 2019). Moreover, transgenic plants produced by exploiting critical genes involved in heavy metal remediation exhibit better efficiency in removing pollutants by reducing their toxicity or aiding in plant growth in the contaminated area (Kafle et al. 2022). Approaches to assess plant growth and metal removal through phytoremediation processes have been discussed later under Section “Approaches to assess plant growth and metal removal through phytoremediation process”. pH, organic matter, radiation, and salinity are the factors influencing the efficiency of phytoremediation (Ali et al.2020). Furthermore, plants adopt several strategies to get rid of toxic contaminants as depicted in Figure 2. The strategies for dealing with environmental chemicals are phytoextraction, phytodegradation, phytovolatilization, and rhizodegradation (Schnoor 1997). The contaminant uptake in plants primarily occurs through the root systems, where the principal mechanisms preventing toxicity of the plants are known to a certain extent. The root system provides an extensive surface area for absorbing and accumulating water, nutrients essential for growth, and other non-essential ions and compounds (Raskin et al. 1997). A brief discussion on the mechanisms adapted during phytoremediation is given below.
Effect of soil quality and planting material on the root architecture and the root anchorage of young hybrid poplar plantations on waste rock slopes
Published in International Journal of Mining, Reclamation and Environment, 2023
Khadija Babi, Marie Guittonny, Bruno Bussière, Guy R. Larocque
Root systems provide both physiological and mechanical functions for plants. The absorption of water and nutrients is primarily performed by fine roots (d < 2 mm), whereas coarse roots (d > 2 mm) provide anchorage for the tree [11; 12]; (Stokes et al., 2005). Coarse root architecture is essentially represented by the spatial configuration of the roots [13] and plays a major role in the root anchorage of the tree, wherein stability is defined as the capacity of a tree’s root system to resist uprooting [14; 15]. The resistance force of a tree varies with its root architecture [16]. Moreover, the angles between roots, the number of roots, root diameters, root system symmetry, and root depths are all known to have significant impacts on anchorage and tree stability [13; 17; 18; 19; 20]; Ruel, 1995 [21; 22]. Despite the importance of these parameters, relatively few belowground investigations have been conducted to evaluate the effects of planting design on root development, especially in the context of revegetation of waste rock slopes.
Ozonized Water in the Preconditioning of Corn Seeds: Physiological Quality and Field Performance
Published in Ozone: Science & Engineering, 2021
Natasha Ohanny da Costa Monteiro, Ernandes Rodrigues de Alencar, Nara Oliveira Silva Souza, Tairone Paiva Leão
As for the effect of preconditioning on the SL (Table 2), there was a more pronounced effect on the seeds of batch A, with a significant effect on RL only in that batch. The importance of these variables is emphasized with regard to seed vigor, which according to Dan et al. (1987), directly influences the final productivity. These authors stated that the root system is responsible for the absorption, assimilation of water and nutrients, and the mechanical support of the plant. Therefore, seedlings and roots of greater length may have more stored energy reserves, favoring establishment in the field in the most adverse conditions, compared to those of shorter length.