Aeolian-fluvial sediments and landscapes along the northwestern Negev Dunefield (Israel) margins since the late Pleistocene

2021 ◽  
Author(s):  
Lotem Robins ◽  
Joel Roskin ◽  
Lupeng Yu ◽  
Noam Greenbaum
Keyword(s):  
Late Pleistocene ◽  
Sudden Change ◽  
High Energy ◽  
Silty Clay ◽  
Arid Environments ◽  
Clay Loam ◽  
Silty Clay Loam ◽  
Fluvial Systems ◽  
Sediment Types ◽  
Wide Range

<p>Dunefield margins are prone to changing domination between aeolian and fluvial systems. Dominating aeolian systems divert or block fluvial systems or/and reduce their erosional forces often leading to amplified sedimentation by a wide range of unique aeolian-fluvial (A-F) sediments. Other arid environments are mainly dominated by eroding ephemeral fluvial systems that usually characterized by sediment degradation.</p><p>The late Pleistocene encroachment of vegetated linear dunes into the northwestern Negev desert dunefield  (Israel) comprised a distinct period of aeolian domination upon ephemeral drainage systems originating in the loess-clad Central Negev highlands. This study analyzes the sediments, geomorphology and landscape evolution caused by A-F processes along dunefield margins, in particular sediments deposited by dune-dammed water bodies slightly upstream of the dunefield edge and between VLDs, using high-resolution field mapping, relative (portable) and absolute OSL dating, stratigraphy and sedimentological analyses. These sediments have been generally mapped as playa sediments, understood to be deposited in a fluvial-dominated environment.</p><p>Six main A-F sediment types were identified and interpreted: (a) Aeolian sand appears to be remnants of fluvial eroded VLD.  (b) Fluvial sand originates from dune erosion and deposited nearby. (c) Massive loam to silty-clay loam relates to abrupt changes in the hydraulic parameters (width/depth ratio and water losses through infiltration) which induce sudden change in flow velocity, resulting in unsorted massive deposits of upstream loess and other desert soil bedload. (d) Couplets, similar to the massive loam, contains loess and upstream sediments deposited in a standing water body. (e) Laminated silty-clay-loam units were identified only between VLDs. (f) High-energy fluvial deposits, which contain loam, sand and pebbles, with  a clear erosional boundary that mark the upstream edge of A-F sedimentation.</p><p>The landscape of the Negev dunefield margins developed since the late Pleistocene by short-term aeolian domination, which gradually changed into fluvial domination during the Holocene. Dune-damming depositions occurred during this transition. First outside the dunefield, then propagated downstream into the dunefield. Fluvial aggradation of A-F sediments resulted in a vast playa-like flats, that following dune-dam breaching underwent incision, let alone in small (~<20 km<sup>2</sup>) basins.</p>

The use of Metribuzin for Weed Control in Tomato

Weed Science ◽  
1974 ◽  
Vol 22 (6) ◽  
pp. 615-619 ◽  
Author(s):  
John Fortino ◽  
Walter E. Splittstoesser
Keyword(s):  
Lycopersicon Esculentum ◽  
Weed Control ◽  
Ultraviolet Light ◽  
Growing Season ◽  
Silty Clay ◽  
Clay Loam ◽  
Silty Clay Loam ◽  
Wide Range ◽  
Direct Seeded ◽  
Tomato Cultivars

Metribuzin [4-amino-6-tert-butyl-3-(methylthio)-as-triazine-5(4H)one] provided adequate preemergence weed control on direct-seeded or transplanted tomato (Lycopersicon esculentumMill.) on Plainfield sand and Drummer silty clay loam soils. Metribuzin demonstrated selective postemergence activity in the field but in glasshouse studies tomato cultivars had a wide range of tolerance to metribuzin applied to the foliage. Tomatoes were more susceptible to injury when they were less than 10-cm tall. Metribuzin was more effective in controlling broadleaf weeds than grass weeds, but grass control was acceptable with higher rates. Ultraviolet light decomposed metribuzin and weed control was improved when metribuzin was incorporated into the soil after application. Metribuzin treatment increased fruit yields. No metribuzin activity was found in the plots by the end of the growing season.

Effect The Treatments of Biofertilizer and Mineral Fertilizer on Content of N P K of Soil Cultivated With Crop Corn (Zea Mays L).

2019 ◽  
Vol 9 (2) ◽  
pp. 247-256
Author(s):  
Mohammed Aajmi Salman ◽  
Jawad A. Kamal Al-Shibani
Keyword(s):  
Zea Mays ◽  
Zea Mays L ◽  
Mineral Fertilizer ◽  
Silty Clay ◽  
Clay Loam ◽  
Potassium Fertilizer ◽  
Clay Loam Soil ◽  
Silty Clay Loam ◽  
Fall Season ◽  
Loam Soil

Beneficial microorganisms play a key role in the availability of ions minerals in the soil and use Randomized Complete Block Desing ( R.C.B.D ). The objective of this paper to the study effect of the of biofertilizer and miniral treatments on availability of NPK for crop corn zea mays L.Two types of biofertilizer are Bacterial Bacillus subtilis and Fungal Trichoderma harianum. Three levels of potassium fertilizer are (2.9533, 0.4000 and 2.9533). A field experiment in fall season of 2018 Has been conducted in silty clay loam soil. The experimental Results indicated that Bacillus and Trichoderma inoculation separately or together Have made a significant effect to increase in the availability of N P K in the soil compare to other treatments. The grain yield is where (2.9533, 0.4000 and 2.9533) of bacterial and fungal bio-fertilizer and potassium fertilizers respectively as compared to the control.

scholarly journals Soil quality of the tea and apple-growing sites in Mindat District, Chin state, Myanmar: A preliminary study

2021 ◽  
Vol 70 (1) ◽  
pp. 27-40
Author(s):  
Yaung Kwee ◽  
Khin Soe
Keyword(s):  
Physicochemical Properties ◽  
Silty Clay ◽  
Subtropical Climate ◽  
Clay Loam ◽  
Silty Clay Loam ◽  
Preliminary Study ◽  
Phosphorus And Potassium ◽  
Very High ◽  
Physicochemical Properties Of Soils

In this study, two sites from tea and apple growing sites were collected from Pyay village and Nine Mile village, Mindat district, Chin state of West Myanmar under a humid subtropical climate. The results of physicochemical properties of observed soils were neutral pH, favorable moisture, silty clay loam texture, very high content of organic carbon, organic matter and total nitrogen. However, the tea growing soil was very poor in phosphorus and potassium content. Moreover, both soils lack of available potassium. The content of heavy metals in both soils was not varied from each other and followed the order: Fe (iron) > Cu (copper) >Zn (zinc) > Pb (lead) > Cr (chromium) and was below the maximum allowed concentrations (MAC). Therefore, the studied soils are generally favorable for cultivation under the condition of application of phosphorus and potassium fertilizers. However, due to the regular application of fertilizers and pesticides, it is necessary to monitor these soils for PTE levels. Further research is recommended, which must include analyses of the physicochemical properties of soils to a two depths of 0-30 and 30-60 cm, especially for the area where fruit plants are grown. In addition, higher density of soil samples and sub-samples are necessary to produce a reliable dataset that will allow proper statistical analysis.

scholarly journals Role of Organic Acids on Phosphorus Fractions in Silty Clay Loam Soil

2018 ◽  
Vol 8 (2) ◽  
pp. 12-21
Author(s):  
Abdulmahdi S.ALansari ◽  
Muhammad M.Yassin ◽  
Mahdi W.Seheib
Keyword(s):  
Humic Acid ◽  
Organic Acids ◽  
Incubation Period ◽  
Total Phosphorus ◽  
Phosphate Fertilizer ◽  
Silty Clay ◽  
Clay Loam ◽  
Silty Clay Loam ◽  
Fertilized Soil

This study was conducted to evaluation the role of the organic acids in the phosphorus fractions in silty clay loam texture. The laboratoryexperiment was conducted by adding the organic acids (Humic acid ,Citric acid ,Oxalic acid , Malic acid ,Acetic acid and Lactic acid )to the fertilized soil with conc. super phosphate fertilizer with 100 kg h-1 level with concentrations (0,15,30,45 and60)mg L-1,except Humic acid (500,1000,1500 and 2000) mg L-1.The soil was incubated at 30 C for 14,28,42,56 and 70 days period and the keep of field capacity about of incubation period during the daily weight.Amount of available ,mineral ,organic and total phosphorus after each incubated period were measured. The results showed that theaddition of organic acids of Humic acid ,Citric acid ,Oxalic acid and Malic acid were caused to increaseamount of available ,mineral ,organic and constant of total phosphorus in fertilized soil with conc. super phosphate fertilizer and increased its amount with increasing of organic acid concentration and better of Humic acid 2000mg L-1 significanton all the treatments .The results of the study that theaddition of organic acids were caused to increase amount of available and mineral phosphorus with increasing of incubation period and constant amount of total phosphorus and decreasing of organic phosphorus amount and available for only soil and only fertilizer treatment during increasing of incubation period .The organic acids can be arranged according to its ability toincrease the availabilityof the phosphorus as follow :

Aggregate slaking during rapid wetting: Hydrophobicity and pore occlusion

2008 ◽  
Vol 88 (1) ◽  
pp. 85-97 ◽  
Author(s):  
Hafida Zaher ◽  
Jean Caron
Keyword(s):  
Organic Matter ◽  
Management Strategies ◽  
Water Entry ◽  
Paper Sludge ◽  
Silty Clay ◽  
Clay Loam ◽  
Wetting Front ◽  
Clay Loam Soil ◽  
Silty Clay Loam ◽  
Loam Soil

The slaking process after rapid wetting is a key factor controlling soil structural stability in dry soil, and an understanding of the relative importance of the different mechanisms involved in slaking may help in the design of management strategies aimed at maintaining a stable surface soil structure. Slaking has been linked to, among other factors, rapid pressure build-up in aggregate, and previous work has emphasized the role of organic matter to hamper that pressure build-up, possibly due to hydrophobicity, reducing rapid water entry within aggregates and hence the build-up. This study emphasizes this latter aspect linked to slaking. The evolution of the intra-aggregate pressure, the matter lost by slaking and the expelled air after rapid wetting of two soils of different textures (clay loam soil and silty-clay loam soil) amended with different types of paper sludge were studied. Hydrophobicity effects were also studied using a tensio-active solution. The results of these experiments showed that when aggregates were submitted to sudden wetting, those treated with paper sludge had an improved resistance to the destructive action of rapid wetting. The lower pressures measured in the aggregates from the amended soils and having less slaking resulted most likely from slow water entry and reduced swelling. Detailed investigation on the link between hydrophobicity and water entry revealed that the true hydrophobic effect (modification of contact angle) was non-existent for the silty-clay loam and minor for the clay loam. This study, rather, suggests that changes in the water potential at the wetting front following organic matter addition and aggregate immersion most likely depend on pore occlusion and on changes in pore surface roughness. Key words: Aggregate stability, organic matter, slaking, pressure, swelling, wettability

Fluometuron in Soil Solution as an Indicator of Its Efficacy in Three Soils

Weed Science ◽  
1982 ◽  
Vol 30 (6) ◽  
pp. 688-691 ◽  
Author(s):  
Michael G. Patterson ◽  
Gale A. Buchanan ◽  
Robert H. Walker ◽  
Richard M. Patterson
Keyword(s):  
Organic Matter ◽  
Field Experiment ◽  
Soil Solution ◽  
Sandy Loam ◽  
Silty Clay ◽  
Clay Loam ◽  
Weed Species ◽  
Silty Clay Loam ◽  
Fine Sandy Loam

Analysis of fluometuron [1,1-dimethyl-3-(α,α,α-trifluoro-m-tolyl)urea] in soil solution after application of 0.5 or 1.0 ppmw revealed up to five-fold differences among three Alabama soils (Lucedale fine sandy loam, Decatur silty clay loam, and Sacul loam). Differences in fluometuron in soil solution were attributed to variable organic matter present and clay fractions. Fluometuron concentration in soil solution for each soil correlated well with control of four broadleaf weed species in a field experiment.

Common Cocklebur Competition in Soybeans

Weed Science ◽  
1974 ◽  
Vol 22 (6) ◽  
pp. 600-603 ◽  
Author(s):  
W. L. Barrentine
Keyword(s):  
Soybean Seed ◽  
Soybean Plant ◽  
Silty Clay ◽  
Clay Loam ◽  
Clay Loam Soil ◽  
Silty Clay Loam ◽  
Competitive Effects ◽  
Loam Soil ◽  
Seed Yields ◽  
Over The Top

The competitive effects of common cocklebur (Xanthium pensylvanicumWallr.) on soybeans[Glycine max(L.) Merr. ‘Lee 68′] were studied on Dundee silty clay loam soil from 1970 to 1972. Full-season competition by common cocklebur at 3,300, 6,600, 13,000, and 26,000 plants/ha reduced the 2-year average soybean seed yields 10, 28, 43, and 52%, respectively. Competition from common cocklebur at 100,000 plants/ha for 4, 6, 8, 10, 12, and 16 weeks after soybean emergence reduced soybean seed yields 10, 36, 40, 60, 80, and 80%, respectively. A reduction in soybean stand occurred after 12 or more weeks competition, and an increase in soybean plant height occurred after 10 or more weeks competition. When common cockleburs were removed during the first 4 weeks after soybean emergence, no further removal was required to obtain maximum soybean yield. Bentazon [3-isopropyl-1H-2,1,3-benzothiadiazin-(4)3H-one 2,2-dioxide] at 1.1 to 2.2 kg/ha applied over-the-top of common cockleburs and soybeans was as effective as hand removal in terminating competition provided common cocklebur plants were not flowering.

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