Proteoid root mats stabilise Hawkesbury Sandstone biomantles following fire

Soil Research ◽  
1998 ◽  
Vol 36 (6) ◽  
pp. 1033 ◽  
Author(s):  
Susan F. Gould
Keyword(s):  
Soil Erosion ◽  
Soil Profile ◽  
Landscape Elements ◽  
Proteoid Roots ◽  
Proteoid Root

The proteoid roots of Banksia serrata L. f. form a dense mat which actively binds biomantle material. In this study, the proteoid root mats of B. serrata L. f. were studied within the context of repeating landscape elements to determine their impact on soil erosion following fire. It was found that proteoid root mats on a Hawkesbury Sandstone hillslope were extensive and positioned high in the soil profile at a time when soils might otherwise be susceptible to soil erosion. On the basis of this evidence, it is concluded that the proteoid roots ofBanksia serrata L. f. stabilise Hawkesbury Sandstone biomantles following bushfire.

scholarly journals Site-Specific Erodibility in Claypan Soils: Dependence on Subsoil Characteristics

2017 ◽  
Vol 33 (5) ◽  
pp. 705-718 ◽  
Author(s):  
Stacey E. Tucker-Kulesza ◽  
Gretchen F. Sassenrath ◽  
Tri Tran ◽  
Weston Koehn ◽  
Lauren Erickson
Keyword(s):  
Electrical Conductivity ◽  
Shear Stress ◽  
Soil Erosion ◽  
Soil Profile ◽  
Crop Production ◽  
Electrical Resistivity Tomography ◽  
Critical Shear Stress ◽  
Productive Capacity ◽  
Clay Layer ◽  
Resistivity Tomography

Abstract. Soil erosion is a primary factor limiting the productive capacity of many crop production fields and contributing to sediment and nutrient impairments of water bodies. Loss of topsoil is especially critical for areas of limited topsoil depth, such as the claypan area of the central United States. More than a century of conventional agricultural practices have eroded the topsoil and, in places, exposed the unproductive clay layer. This clay layer is impervious, limiting water infiltration and root penetration, and severely restricting agricultural productivity. Previous studies have documented changes in topsoil thickness using apparent electrical conductivity (ECa). However, that methodology is limited by its shallow depth of measurement within the soil profile, and as such cannot adequately explore factors within the soil profile that potentially contribute to topsoil erosion. In this study, we identified areas of limited topsoil depth using crop yields and ECa. Two areas within the production field varying in crop production and ECa were selected for detailed measurements using Electrical Resistivity Tomography. This methodology allowed delineation of soil stratigraphy to a depth of 5.3 m. The erodibility of undisturbed soil samples from the two areas were measured in an Erosion Function Apparatus to obtain the critical shear stress, or the applied stress at which soil begins to erode. Based on resistivity measurement, the highly productive region of the field had a thick (1.0-2.0 m) soil layer of saturated clayey sand soil over a uniform sandy material, with minimal clay layer. This soil had a critical shear stress of 12 Pa. The extent of historical erosion was evident in the poorly-producing area, as only a thin band of topsoil material remained over a thicker clay layer. The unproductive area with exposed clay layer had a critical shear stress of 128 Pa, indicating it was more resistant to erosion than the highly productive region. The clay layer was found to extend to 1.3-1.5 m in depth in the soil profile in the poorly producing area. Below this layer was a layer with similar resistivity to the high-producing region. The data reveal the extent of historical erosion within the crop production field and highlight significant variability in measured soil properties within a field of identical production practices. While spatial variations in topsoil have long been considered in developing management practices to improve soil health and productive capacity, our results indicate the importance of identifying variability of subsoil characteristics to address long-term impacts on soil erosion and productivity. Keywords: Soil erosion, Soil electrical conductivity, Claypan soil, Productive capacity, Electrical resistivity tomography.

The morphology and anatomy of proteoid roots in the genus Hakea

1972 ◽  
Vol 20 (2) ◽  
pp. 155 ◽  
Author(s):  
B Lamont
Keyword(s):  
Special Reference ◽  
Root System ◽  
Plant Age ◽  
Proteoid Roots ◽  
Relative Contribution ◽  
Endophytic Microorganisms ◽  
As Species ◽  
The Family ◽  
Proteoid Root

This paper extends the introductory work of Purnell(1960) on proteoid roots in the family Proteaceae by a detailed study of the genus Hakea, with special reference to H. prostrata. The presence of proteoid roots is reported in 63 Hakea species. Their relative contribution to the root system is related to such plant factors as species, age, and cotyledon size. The dimensions of proteoid roots are dependent on plant age and species. The morphology and anatomy of these structures are described. Endophytic microorganisms are not normally associated with proteoid roots. Proteoid rootlets survive 2-3 months, though their parent roots last indefinitely. Proteoid roots are produced by the youngest roots in the root system. While proteoid rootlets arise laterally, the parent root may arise either laterally or adventitiously. Both proteoid and non-proteoid roots may be initiated within a proteoid root.

Effects of Content of Soil Rock Fragments on Calculating of Soil Erodibility

2021 ◽  
Author(s):  
Miaomiao Yang ◽  
Qinke Yang ◽  
Keli Zhang ◽  
Yuru Li ◽  
Chunmei Wang ◽  
...  
Keyword(s):  
Hydraulic Conductivity ◽  
Soil Erosion ◽  
Soil Profile ◽  
Joint Effect ◽  
Saturated Hydraulic Conductivity ◽  
Soil Erodibility ◽  
Soil Permeability ◽  
Land Area ◽  
Rock Fragments ◽  
Global Land

<p>【Objective】Rock fragments (>2mm diameter) are an important component of soil, and its presence has a significant impact on soil erosion and sediment yield. So it is essential to take into full account content of the rock fragments for accurate calculation of soil erodibility factor (K). 【Method】In this paper, based on the data available of the content of rock fragments and classes of soil texture with a resolution of 30 arc-second, influence of the content of rock fragments, including rock fragments in the soil profile (RFP) and gravels on the surface of the soil (SC), on K was assessed at a global scale, using the equation (Brakensiek, 1986) of the relationship between saturated hydraulic conductivity and grade of soil permeability, and the equation (Poesen) of soil erodibility attenuation under a rock fragment cover. 【Result】Results show: (1) The existence of rock fragments in the soil increased K by 4.43% and soil permeability by 5.68% on average in grade and lowering soil saturated hydraulic conductivity by 11.57% by reducing water infiltration rate of the soil and increasing surface runoff. The gravels on the surface of the mountain land and desert/gobi reduced K by 18.7% by protecting the soil from splashing of rain drops and scrubbing of runoff; so once the content of rock fragments in the soil profile and gravels on the surface of the land are taken into account in calculation, soil K may be 5.52% lower; (2)In the areas dominated with the effect of rock fragments, about 62.7% of the global land area, soil K decreased by 0.0091( t•hm<sup>2</sup>•h)•( hm<sup>-2</sup>•MJ<sup>-1</sup>•mm<sup>-1</sup>) on average, while in the area affected mainly by rock fragments in profile, about 31.1% of the global land area, soil K increased by 0.0019( t•hm<sup>2</sup>•h)•( hm<sup>-2</sup>•MJ<sup>-1</sup>•mm<sup>-1</sup>); and (3)The joint effect of rock fragments in profile and gravels on the surface reduced the soil erosion rate by 11.8% in the 6 sample areas. 【Conclusion】 The presence of RFP increases soil K while the presence of SC does reversely. The joint effect of the two leads to decrease in soil erosion. In plotting regional soil erosion maps, it is essential to take both of the two into account so as to improve accuracy of the mapping.</p>

Predicting the impact of linear landscape elements on surface runoff, soil erosion, and sedimentation in the Wahnbach catchment, Germany

2011 ◽  
Vol 26 (11) ◽  
pp. 1642-1654 ◽  
Author(s):  
Herwig Hölzel ◽  
Bernd Diekkrüger
Keyword(s):  
Soil Erosion ◽  
Surface Runoff ◽  
Landscape Elements ◽  
Linear Landscape Elements ◽  
The Impact

Spatial variability of 137Cs-drived total soil erosion rate and its driving factors at regional scale: a meta-analysis in China’s Loess Plateau

2020 ◽  
Author(s):  
Jian Hu ◽  
Yihe Lü ◽  
Bojie Fu ◽  
Alexis J Comber ◽  
Lianhai Wu ◽  
...  
Keyword(s):  
Soil Erosion ◽  
Soil Profile ◽  
Erosion Rate ◽  
No Tillage ◽  
Land Uses ◽  
Erosion Rates ◽  
Soil Erosion Rate ◽  
Profile Distribution ◽  
Tracing Method

<p>Soil erosion, contributing to land degradation, was identified as an essential driving factor for the evolution of Earth’s critical zone. Although runoff plots along the slope and weirs on river valleys are often used to monitor short-term soil and water loss, it is usually difficult to evaluate the long-term soil loss rates across spatial scales. The <sup>137</sup>Cs tracer can effectively measure the long-term soil erosion rates but its capability to quantify regional soil erosion characteristics and the driving mechanisms remains a big challenge. To deal with this gap, we integrated and synthesized 61 peer-reviewed articles of soil erosion research by using <sup>137</sup>Cs tracer methods in the Loess Plateau of China to reveal the regional variability of soil erosion and the effects of land uses on (a) reference <sup>137</sup>Cs inventory, (b) <sup>137</sup>Cs soil profile distribution and (c) <sup>137</sup>Cs-derived total measured erosion rate. The results showed that reference <sup>137</sup>Cs inventory range from 900 to 1750 Bq/m<sup>2</sup> with a mean value of 1351 Bq/m<sup>2</sup>. The reference <sup>137</sup>Cs inventory decreased significantly with the increase of latitude and longitude (p<0.001), while it didn’t change obviously with the mean annual precipitation and temperature. The assumption of <sup>137</sup>Cs tracing method was supported by <sup>137</sup>Cs soil profile distribution under tillage and un-disturbed land. Tillage land was considered to have uniform distribution in soil profile and a similar exponential distribution of <sup>137</sup>Cs content can be found in terrace and no-tillage land. Furthermore, <sup>137</sup>Cs loss percent had a significant positive relationship with soil erosion rate (p<0.001). Average long-term soil erosion rate of cropland was more than 15000 t/(km<sup>2</sup>·a) and significantly higher than no-tillage land (5462.52 t/(km<sup>2</sup>·a) including that of grassland (3890.86 t/(km<sup>2</sup>·a)), forest (>6000 t/(km<sup>2</sup>·a)), and terrace (<5000 t/(km<sup>2</sup>·a)) (p<0.001). The average long-term soil erosion rate of cropland presented high spatial variability and loess hill and gully region had significantly higher average long-term soil erosion rate on cropland due to the coupling effects between heavy rainfall and steep slope. Appropriate reference sites and soil erosion conversion models were important factors for accurately quantifying the long-term soil erosion while the variation of climate, land uses, and geomorphic types had significant impacts on the spatial distribution of erosion rates. Our study can facilitate the understanding of the <sup>137</sup>Cs tracing method for long-term soil erosion rate and its spatial pattern, which can be supportive for soil and water conservation planning and relevant policy-making.</p>

The Effects of Seasonality and Waterlogging on the Root Systems of a Number of Hakea Species

1976 ◽  
Vol 24 (6) ◽  
pp. 691 ◽  
Author(s):  
B Lamont
Keyword(s):  
Redox Potential ◽  
Root System ◽  
Water Availability ◽  
Field Capacity ◽  
Climatic Conditions ◽  
Root Weight ◽  
Proteoid Roots ◽  
Growth Increase ◽  
Steep Decline ◽  
Proteoid Root

Proteoid and non-proteoid roots are produced only during winter-spring under the Mediterranean climatic conditions of south-western Australia. However, dormant roots can be induced to form new root structures in summer, if sufficient water is applied to that part of the root system. The seasonal occurrence of proteoid roots is therefore due to the annual variation in water available for growth of the surface parent roots. Both proteoid and non-proteoid root growth increase as water availability is increased from the permanent wilting point to one to two times field capacity, with a trebling in the proportion of proteoid roots by weight in the root system. This is followed by a steep decline in total root weight and in the proportion of proteoid roots in the root system as water availability is increased from two to three times field capacity. While the size of proteoid roots is greatest under non-waterlogged conditions (redox potential of 450-550 mV), their number per unit total root weight is greatest under moderately waterlogged conditions (redox potential of 120-350 mV).

Factors affecting the distribution of proteoid roots within the root systems of two Hakea species

1973 ◽  
Vol 21 (2) ◽  
pp. 165 ◽  
Author(s):  
B Lamont
Keyword(s):  
Organic Matter ◽  
Root System ◽  
Root Systems ◽  
Physical Factors ◽  
Root Weight ◽  
Local Concentration ◽  
Horizontal Distance ◽  
Proteoid Roots ◽  
Local Soil ◽  
Proteoid Root

The proteoid roots of Hakea prostrata and H. laurina are concentrated in the surface soil horizons, even though the root systems penetrate to much greater depths. The relationships of a number of soil and plant factors to proteoid root occurrence in a given portion of the root system were examined. Pockets of humus-rich soil in any part of the root system greatly increased the proteoid root concentration in that region. The following factors, listed in their apparent order of importance, were analysed: local concentration of parent roots, local level of soil organic matter, local nitrogen availability, shoot growth, nitrogen concentration of the shoots, vertical distance of the region from the soil surface, local availability of calcium, magnesium, and potassium, local bulk density and certain other physical factors, nutrient status of the rest of the root system, horizontal distance of the region from the centre of the plant, relative maturity of parent roots in the region, and local soil pH and certain other chemical factors. The nitrogen component of soil regions high in organic matter largely accounted for their higher non-proteoid root concentration, smaller proteoid root size, greater number of laterals, and longer roots per unit weight, but not their much greater number of proteoid roots per unit total root weight. This suggests that other factors are also involved in proteoid root formation.

The Effect of Soil Nutrients on the Production of Proteoid Roots by Hakea Species

1972 ◽  
Vol 20 (1) ◽  
pp. 27 ◽  
Author(s):  
B Lamont
Keyword(s):  
Root Growth ◽  
Response Curve ◽  
Nitrogen Availability ◽  
Root Production ◽  
Proteoid Roots ◽  
Relative Contribution ◽  
Root Response ◽  
Proteoid Root ◽  
Two Phases ◽  
The Relationship

The mode of the proteoid root response curve occurs at a considerably lower level of nitrogen or phosphorus than that of the response curve for non-proteoid roots. As a consequence, the relationship between proteoid and non-proteoid roots can be regarded as passing through four phases as nutrient availability increases: (a) an increase in proteoid root production as non-proteoid root growth increases; (b) a decrease in proteoid root production as non-proteoid root growth increases; (c) a decrease in proteoid root production as non-proteoid root growth decreases; (d) an absence of proteoid roots as non-proteoid root growth decreases. Only the first two phases are considered relevant to plants growing under field conditions. It is concluded that nutrient concentration in a number of soils, especially nitrogen availability, largely determines the relative contribution of proteoid roots to the root systems of two species of Hakea.

Chemical Characteristics of the Proteoid Root Mat of Banksia integrifolia L

1989 ◽  
Vol 37 (2) ◽  
pp. 137 ◽  
Author(s):  
PF Grierson ◽  
PM Attiwill
Keyword(s):  
Surface Soil ◽  
Root Zone ◽  
Chelating Agent ◽  
Chemical Characteristics ◽  
Hydrogen Ions ◽  
Litter Layer ◽  
Soil Environment ◽  
Proteoid Roots ◽  
Water Extracts ◽  
Proteoid Root

The proteoid roots of Banksia integrifolia are concentrated in the surface soil, forming a dense mat beneath the litter layer. Water extracts of the proteoid root mat contained a significantly greater amount of hydrogen ions, reductants and an unidentified chelating agent, than water extracts of soil beneath the root mat, of the litter layer and of soil from beyond the proteoid root zone. The results are discussed in relation to previously reported production of organic chelates by plants causing solubilisation of soil phosphates. It is suggested the proteoid roots of B. integrifolia chemically modify the soil environment thereby enhancing nutrient uptake.

scholarly journals Effects of Content of Soil Rock Fragments on Soil Erodibility in China

2022 ◽  
Vol 19 (2) ◽  
pp. 648
Author(s):  
Miaomiao Yang ◽  
Keli Zhang ◽  
Chenlu Huang ◽  
Qinke Yang
Keyword(s):  
Land Use ◽  
Soil Erosion ◽  
Soil Type ◽  
Soil Profile ◽  
Redundancy Analysis ◽  
Vegetation Index ◽  
Vegetation Coverage ◽  
Soil Erodibility ◽  
Rock Fragments ◽  
Normalised Difference Vegetation Index

Soil erosion is serious in China—the soil in plateau and mountain areas contain a large of rock fragments, and their content and distribution have an important influence on soil erosion. However, there are still no complete results for calculating soil erodibility factor (K) that have corrected rock fragments in China. In this paper, the data available on rock fragments in the soil profile (RFP); rock fragments on the surface of the soil (RFS); and environmental factors such as elevation, terrain relief, slope, vegetation coverage (characterised by normalised difference vegetation index, NDVI), land use, precipitation, temperature, and soil type were used to explore the effects of content of soil rock fragments on calculating of K in China. The correlation analysis, typical sampling area analysis, and redundancy analysis were applied to analyse the effects of content of soil rock fragments on calculating of K and its relationship with environment factors. The results showed that (1) The rock fragments in the soil profile (RFP) increased K. The rock fragments on the surface (RFS) of the soil reduced K. The effect of both RFP and RFS reduced K. (2) The effect of rock fragments on K was most affected by elevation, followed by terrain relief, NDVI, slope, soil type, temperature, and precipitation, but had little correlation with land use. (3) The result of redundancy analysis showed elevation to be the main predominant factor of the effect of rock fragments on K. This study fully considered the effect of rock fragments on calculating of K and carried out a quantitative analysis of the factors affecting the effect of rock fragments on K, so as to provide necessary scientific basis for estimating K and evaluating soil erosion status in China more accurately.

Sign in / Sign up

Export Citation Format

Share Document