Mapping tree root system in dikes using induced polarization: Focus on the influence of soil water content

Tree root system development alters forest soil properties, and differences in root diameter frequency and root length per soil volume reflect differences in root system function. In this study, the relationship between vertical distribution of very fine root and soil water content was investigated in intact tree and cut tree areas. The vertical distribution of root density with different diameter classes (very fine <0.5 mm and fine 0.5–2.0 mm) and soil water content were examined along a slope with two coniferous tree species, Cryptomeria japonica (L.f.) D. Don and Chamaecyparis obtusa (Siebold et Zucc.) Endl. The root biomass and length density of very fine roots at soil depth of 0–5 cm were higher in the Ch. obtusa intact tree plot than in the Cr. japonica intact plot. Tree cutting caused a reduction in the biomass and length of very fine roots at 0–5 cm soil depth, and an increment in soil water content at 5–30 cm soil depth of the Ch. obtusa cut tree plot one year after cutting. However, very fine root density of the Cr. japonica intact tree plot was quite low and the soil water content in post-harvest areas did not change. The increase in soil water content at 5–30 cm soil depth of the Ch. obtusa cut tree plot could be caused by the decrease in very fine roots at 0–5 cm soil depth. These results suggest that the distribution of soil water content was changed after tree cutting of Ch. obtusa by the channels generated by the decay of very fine roots. It was also shown that differences in root system characteristics among different tree species affect soil water properties after cutting.

Download Full-text

Root length density and soil water distribution in drip-irrigated olive orchards in Argentina under arid conditions

Crop and Pasture Science ◽

10.1071/cp08135 ◽

2009 ◽

Vol 60 (3) ◽

pp. 280 ◽

Cited By ~ 16

Author(s):

Peter S. Searles ◽

Diego A. Saravia ◽

M. Cecilia Rousseaux

Keyword(s):

Water Content ◽

Root System ◽

Soil Water ◽

Soil Water Content ◽

Root Length ◽

Root Length Density ◽

Soil Depth ◽

Drip Line ◽

North West ◽

Intensively Managed

Several studies have evaluated many above-ground aspects of olive production, but essential root system characteristics have been little examined. The objective of our study was to evaluate root length density (RLD) and root distribution relative to soil water content in three commercial orchards (north-west Argentina). Depending on the orchard, the different drip emitter arrangements included either: (1) emitters spaced continuously at 1-m intervals along the drip line (CE-4; 4 emitters per tree); (2) 4 emitters per tree spaced at 1-m intervals, but with a space of 2 m between emitters of neighbouring trees (E-4); or (3) 2 emitters per tree with 4 m between emitters of neighbouring trees (E-2). All of the orchards included either var. Manzanilla fina or Manzanilla reina trees (5–8 years old) growing in sandy soils, although the specific characteristics of each orchard differed. Root length density values (2.5–3.5 cm/cm3) in the upper soil depth (0–0.5 m) were fairly uniform along the drip line in the continuous emitter (CE-4) orchard. In contrast, roots were more concentrated in the E-4 and E-2 orchards, in some cases with maximum RLD values of up to 7 cm/cm3. Approximately 70% of the root system was located in the upper 0.5 m of soil depth, and most of the roots were within 0.5 m of the drip line. For each of the three orchards, significant linear relationships between soil water content and RLD were detected based on 42 sampling positions that included various distances from the trunk and soil depths. Values of RLD averaged over the entire rooting zone and total tree root length per leaf area for the three orchards were estimated to range from 0.19 to 0.48 cm/cm3 and from 1.8 to 3.5 km/m2, respectively. These results should reduce the uncertainty associated with the magnitude of RLD values under drip irrigation as intensively managed olive orchards continue to expand in established and new growing regions.

Download Full-text

Soil moisture heterogeneity during deficit irrigation alters root-to-shoot signalling of abscisic acid

Functional Plant Biology ◽

10.1071/fp07009 ◽

2007 ◽

Vol 34 (5) ◽

pp. 439 ◽

Cited By ~ 60

Author(s):

Ian C. Dodd

Keyword(s):

Water Content ◽

Root System ◽

Soil Water ◽

Soil Water Content ◽

Deficit Irrigation ◽

Plant Root ◽

Arithmetic Mean ◽

Similar Amount ◽

Graft Union ◽

Plant Root System

The effects of different irrigation techniques on leaf xylem ABA concentration ([X-ABA]leaf) were compared in tomato (Lycopersicon esculentum Mill.). During partial rootzone drying (PRD), water was distributed unevenly to the root system such that part was irrigated while the remainder was allowed to dry the soil. During conventional deficit irrigation (DI), plants received the same volume of water as PRD plants, but water was distributed evenly to the entire root system. When the plant root system was allowed to explore two separate soil compartments, DI plants had a higher [X-ABA]leaf than PRD plants with moderate soil drying, but PRD plants had a higher [X-ABA]leaf than DI plants as the soil dried further. The difference in [X-ABA]leaf between the two sets of plants was not because of differences in either whole pot soil water content (θpot) or leaf water potential (Ψleaf). To investigate the contribution of different parts of the root system to [X-ABA]leaf, individual shoots were grafted onto the root systems of two plants grown in two separate pots, so that the graft union had the appearance of an inverted ‘Y’. After sap collection from detached leaves, removal of the shoot below the graft union allowed sap collection from each root system. Again, DI plants had a higher [X-ABA]leaf than PRD plants when the soil was relatively wet, but the opposite occurred as the soil dried. Root xylem ABA concentration ([X-ABA]root) increased exponentially as soil water content (θ) declined. In DI plants, [X-ABA]root from either pot (or the arithmetic mean of [X-ABA]root) accounted for a similar amount of the variation in [X-ABA]leaf. In PRD plants, [X-ABA]root from the watered side underestimated [X-ABA]leaf, whereas [X-ABA]root from the dry side overestimated [X-ABA]leaf. The arithmetic mean of [X-ABA]root best explained the variation in [X-ABA]leaf, implying continued sap flow from the dry part of the root system (Jdry) at soil water potentials (Ψsoil) at which Jdry had ceased in previous studies of PRD plants (Yao et al. 2001). Evaluating the relationship between Jdry and Ψsoil may assist in maintaining export of ABA (and other growth regulators) from the drying part of the root system, to achieve desirable horticultural outcomes during PRD.

Download Full-text

The Development of the Root System of the Winter Annual Desert Plant Anastatica hiërochuntica L. The Significance of Soil Water Content and Nutrient Supply

Flora ◽

10.1016/s0367-2530(17)30525-x ◽

1992 ◽

Vol 186 (1-2) ◽

pp. 117-125 ◽

Cited By ~ 2

Author(s):

Wolfram Hartung ◽

Herrmann Heilmeier

Keyword(s):

Water Content ◽

Root System ◽

Soil Water ◽

Soil Water Content ◽

Nutrient Supply ◽

Desert Plant ◽

Winter Annual

Download Full-text

NMR imaging for measuring root system and soil water content.

Environment Control in Biology ◽

10.2525/ecb1963.23.99 ◽

1985 ◽

Vol 23 (4) ◽

pp. 99-102 ◽

Cited By ~ 31

Author(s):

Kenji OMASA ◽

Morio ONOE ◽

Hiroaki YAMADA

Keyword(s):

Water Content ◽

Root System ◽

Soil Water ◽

Soil Water Content ◽

Nmr Imaging

Download Full-text

Fibrous root growth and water use of sugar beet

The Journal of Agricultural Science ◽

10.1017/s0021859600059591 ◽

1985 ◽

Vol 105 (3) ◽

pp. 679-691 ◽

Cited By ~ 46

Author(s):

Kay F. Brown ◽

P. V. Biscoe

Keyword(s):

Sugar Beet ◽

Winter Wheat ◽

Water Content ◽

Root System ◽

Soil Water ◽

Soil Water Content ◽

Water Use ◽

Root Density ◽

Published Data ◽

Fibrous Root

SUMMARYDevelopment of the fibrous root system of sugar beet was studied by washing soil samples taken from field experiments through the growing season. At the beginning of June the root system was still poorly developed but during June there was rapid proliferation. In the top 70 cm there was only little further increase in root density after the end of June. Below 70 cm root density increased up to the end of August. Throughout the season fibrous root density decreased with depth. Despite the origin of the lateral roots from two grooves on the storage root, fibrous root distributions at each depth around individual plants were essentially uniform from mid-June onwards. In the absence of nitrogen fertilizer, fibrous root development exceeded that of a crop given fertilizer, particularly at depths greater than 50 cm early in the season. The maximum value of root density was 2·8 cm/cm3 soil recorded in the top 10 cm in mid-September. Compared with published data for other crops, the sugar-beet root system was sparser than that of winter wheat or maize but denser than that of a soya bean or cassava.Soil water content was measured with a neutron probe. Inflows to roots were calculated from soil water content changes in different soil layers. In the top 30 cm, inflows ranged up to 10·8 μl water/cm root.day and were up to five times higher than published inflows for winter wheat. At 30–100 cm sugar beet and winter wheat inflows were generally similar. The 0–30 and 30–120 cm layers contributed about 80 and 20% respectively of the total water use by sugar beet while no uptake was recorded below 110 cm. Previous studies have shown that sugar beet often takes up water from soil deeper than 110 cm, although it is not unknown for the depth of water removal to be restricted.

Download Full-text

SOIL WATER CONTENT AFFECTS THE AVAILABILITY OF PHOSPHATE

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.1985.46.1696 ◽

1985 ◽

pp. 185-189

Author(s):

M.C.H.Mouat Pieter Nes

Keyword(s):

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Soil Solution ◽

Equivalent Reduction

Reduction in water content of a soil increased the concentration of ammonium and nitrate in solution, but had no effect on the concentration of phosphate. The corresponding reduction in the quantity of phosphate in solution caused an equivalent reduction in the response of ryegrass to applied phosphate. Keywords: soil solution, soil water content, phosphate, ryegrass, nutrition.

Download Full-text

Effect of inter-row cultivation on soil carbon dioxide emission in a peach plantation

Agrokémia és Talajtan ◽

10.1556/agrokem.59.2010.1.19 ◽

2010 ◽

Vol 59 (1) ◽

pp. 157-164 ◽

Cited By ~ 1

Author(s):

E. Tóth ◽

Cs. Farkas

Keyword(s):

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Carbon Dioxide Emission ◽

Nutrient Content ◽

Soil Disturbance ◽

Biological Properties ◽

Soil Tillage ◽

Favourable Effect ◽

Volumetric Soil Water Content

Soil biological properties and CO2emission were compared in undisturbed grass and regularly disked rows of a peach plantation. Higher nutrient content and biological activity were found in the undisturbed, grass-covered rows. Significantly higher CO2fluxes were measured in this treatment at almost all the measurement times, in all the soil water content ranges, except the one in which the volumetric soil water content was higher than 45%. The obtained results indicated that in addition to the favourable effect of soil tillage on soil aeration, regular soil disturbance reduces soil microbial activity and soil CO2emission.

Download Full-text