Effect of soil type on burrowing behavior and cocoon formation in the green-striped burrowing frog, Cyclorana alboguttata

2006 ◽  
Vol 84 (6) ◽  
pp. 832-838 ◽  
Author(s):  
D.T. Booth

This study examined the effect of soil type on burrowing behaviour and cocoon formation during aestivation in the green-striped burrowing frog, Cyclorana alboguttata (Günther, 1867). Given a choice, frogs always chose to burrow in wet sand in preference to wet clay. Frogs buried themselves faster and dug deeper burrows in sandy soil. However, under my laboratory conditions, there was little difference in the pattern of soil drying between the two soil types. Frogs in both sand and clay soil experienced hydrating conditions for the first 3 months and dehydrating conditions for the last 3 months of the 6-month aestivation period, and cocoons were not formed until after 3 months of aestivation. After 6 months, there were more layers in the cocoons of frogs aestivating in sand than those aestivating in clay. Frogs were able to absorb water from sandy soil with water potentials greater than –400 kPa, but lost water when placed on sand with a water potential of –1000 kPa.

2000 ◽  
Vol 53 ◽  
pp. 253-257
Author(s):  
T.K. James ◽  
A. Rahman

The viability of ragwort (Senecio jacobaea L) seed buried for several years at 0 2 4 6 and 19 21 cm depths was evaluated in four different soil types Seed samples in nylon mesh bags were removed after 1 2 3 5 11 and 16 years burial and their viability determined by germination After 16 years no viable seed was found in the clay soil In the silt loam and peat soils 1 3 viable seed remained while in the sandy soil up to 13 remained viable In the surface 0 2 cm layer of soil it took from 109 to 146 years for the percentage of viable seed to fall to 1 of the original viable seed depending on soil type At the 4 6 and 19 21 cm depths the corresponding times were 128 165 years and 130 180 years


Agrikultura ◽  
2017 ◽  
Vol 28 (1) ◽  
Author(s):  
Fizrul Indra Lubis ◽  
Sudarjat Sudarjat ◽  
Danar Dono

ABSTRACTPopulation of soil palm weevil pollinator Elaeidobius kamerunicus FAUST and its impact on fruit setvalue at clay, sandy and peat soil types in central Kalimantan, di IndonesiaOil palm weevil pollinator Elaeidobius kamerunicus Faust plays an important role in the increasing oilpalm fruit set value. Along with the development of oil palm, fruit set problems occurred in recentdecades in some parts of Indonesia. An experiment was carried out on a seven years old oil palmplantation located at Selangkun Estate, Kotawaringin Barat, Central Kalimantan, Indonesia to find outthe influence of population E. kamerunicus on pollination efficiency at clay, sandy and peat soil types.Relative to other soil types, a high weevil population on male (50,811 weevils/ha ; 72 weevils/spikelet)and female (219 weevils) inflorescences had been recorded at clay soil. Fruit set value on clay soil 58.9%and significantly different with sandy soil of 49.8% and peat soil of 46.4%. Population E. kamerunicusper ha influenced fruit set value at clay, sandy and peat soil types. Number of E. kamerunicus visitedfemale inflorescences did not influenced fruit set value at clay, sandy and peat soil types.Keywords: Clay soil, Elaeidobius kamerunicus, fruit set, peat soil, population, sandy soil ABSTRAKSerangga penyerbuk kelapa sawit Elaeidobius kamerunicus FAUST berperan penting dalam peningkatannilai fruit set kelapa sawit. Seiring dengan perkembangan kelapa sawit, adanya permasalahan nilai fruitset telah terjadi dalam beberapa kurun waktu di beberapa wilayah Indonesia. Penelitian dilakukan diperkebunan kelapa sawit yang telah berumur tujuh tahun, berlokasi di Selangkung, Kotawaringin Barat,Kalimantan Tengah, Indonesia dan bertujuan untuk mengetahui pengaruh populasi E. Kamerunicusterhadap efisiensi penyerbukan pada tipe tanah liat, pasir dan gambut. Berdasarkan tipe tanahdilaporkan bahwa tingginya populasi kumbang pada bunga jantan yaitu (50.811 kumbang/ha; 72kumbang/spikelet) dan bunga betina yang sedang mekar (219 kumbang) pada tipe tanah berliat.Adapun, nilai fruit set pada tanah liat sebesar 58,9% dan berbeda nyata dibandingkan dengan tanahberpasir (49,8%) dan gambut (46,4%). Populasi E. kamerunicus per ha berpengaruh terhadap nilai fruitset pada tipe tanah liat, pasir dan gambut. Namun, jumlah E. kamerunicus yang mengunjungi bungabetina yang sedang mekar tidak berpengaruh terhadap nilai fruit set pada tipe tanah liat, pasir dangambut.Kata Kunci : Elaeidobius kamerunicus, Fruit set , Populasi, Tanah Gambut, Tanah liat, Tanah Pasir


2013 ◽  
Vol 33 (5) ◽  
pp. 965-975 ◽  
Author(s):  
Aloisio Bianchini ◽  
Pedro H. de M. Borges

The destruction of the cotton crop residues (cotton stalks) is a mandatory procedure in Brazil for prophylactic issues, but is a subject unexplored by the research and there are few studies that deal with this issue. However, this is not encouraged in recent decades, studies aimed at developing and evaluating equipment for this purpose. The present study had the objective to evaluate six methods for mechanical destruction of cotton crop residues. Each method was defined based on the principle of operation of the active parts of the equipment, which were tested in medium texture soil and in a clayey one. The variables used to evaluate the efficiency of the equipment were the regrowth rate, the theoretical field capacity and energy demand. The equipment with convergent concave disks (DCC) and flat cutters discs from manufacturer A (CPS-a) showed the best results in cotton stalks destruction in both soil types. The harrow disc (GPD) was efficient only in clay soil. It was concluded that the equipment with convergent concave disks, among those tested, was the most efficient to destroy cotton stalks, regardless of soil type, and that the harrow disc was not included among the best performers.


2007 ◽  
Vol 47 (12) ◽  
pp. 1484 ◽  
Author(s):  
B. Ben Rouina ◽  
A. Trigui ◽  
R. d'Andria ◽  
M. Boukhris ◽  
M. Chaïeb

In Tunisia, olives are grown under severe rain-fed, arid conditions. To determine the behaviour of olive trees (cv. Chemlali Sfax) during the severe drought affecting Tunisian arid areas in 2002, a range of physiological parameters were investigated in three adjacent orchards. Two olive orchards were rain-fed, one located on a sandy soil, and the other on a sandy-loam clay soil. A third orchard was also located on sandy soil, but received remedial irrigation (415 mm of water per year; ~40% of olive evapotranspiration). Predawn leaf water potential (Ψpd) did not fall below –1.52 MPa for irrigated olive trees. However, a large decrease in Ψpd was observed for rain-fed olive trees in the same period with Ψpd measured at about –3.2 MPa on sandy soil and –3.6 MPa on sandy-loam clay soil. At the same time, the minimal leaf water potential recorded at midday (Ψmin) decreased to –4.15 MPa and –4.71 MPa in the rain-fed trees for sandy and sandy-loam clay soil, respectively. For irrigated trees, the Ψmin was –1.95 MPa. These results were associated with relative water content, which varied from 80% for irrigated trees to 54 and 43.6%, respectively, for rain-fed trees and trees subjected to severe drought. In August, when the relative water content values were less than 50%, a progressive desiccation in the outer layer of canopy and death of terminal shoots were observed in trees, which grew on the sandy-loam clay soil. Furthermore, low soil water availability also affected (negatively) the net photosynthetic rate in rain-fed orchards (10.3 µmol/m2.s for irrigated trees v. 5.3 µmol/m2.s in rain-fed trees on sandy soil) and stomatal conductance (98.5 mmol/m2.s v. 69.3 mmol/m2.s). However, it improved water use efficiency (7.6 v. 4.7 µmol CO2/mmol H2O), which increased by more than 50% in both groups of rain-fed trees compared with the irrigated ones. We can conclude that olive trees respond to drought by showing significant changes in their physiological and biological mechanisms. These results also help our understanding of how olive trees cope with water stress in the field and how marginal soils can restrict growth and lower yields.


Agronomy ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1391
Author(s):  
Xizi Wang ◽  
Svend Christensen ◽  
Jesper Svensgaard ◽  
Signe M. Jensen ◽  
Fulai Liu

There is an urgent need among plant breeders for a deeper understanding of the links between wheat genotypes and their ability to utilize light for biomass production and their efficiency at converting the biomass into grain yield. This field trail was conducted to investigate the variations in radiation use efficiency (RUE) and harvest index (HI) of four spring wheat cultivars grown on two soil types with two nitrogen (N) fertilization levels. Grain yield (GY) was significantly higher with 200 kg N ha−1 than 100 kg N ha−1 and on clay soil than on sandy soil, and a similar trend was observed for shoot dry matter (DM) at maturity. RUE and HI was neither affected by cultivar nor N-fertilization, but was affected by soil type, with a significantly higher RUE and HI on clay than on sandy soil. The differences of water holding capacity between the two soil types was suggested to be a major factor influencing RUE and HI as exemplified by the principal component analysis. Thus, to achieve a high RUE and/or HI, sustaining a good soil water status during the critical growth stages of wheat crops is essential, especially on sandy soils with a low water holding capacity.


1995 ◽  
Vol 69 (1) ◽  
pp. 1-5 ◽  
Author(s):  
M.O. Ajala ◽  
S.O. Asaolu

AbstractThe efficacy of the salt flotation technique using saturated solutions of sodium nitrate (specific gravity 1.30) and zinc sulphate (specific gravity 1.16) for separating Ascaris lumbricoides eggs from clay, loamy and sandy soils has been investigated. Ten samples of each of the egg concentrations of 100, 500, 2500, 5000 and 10,000 eggs/25 g of soil were used for each soil type. Using T-test and ANOVA, the number of eggs recovered from sand was significantly higher than from loam and the number from loam significantly higher than from clay. With sodium nitrate, the maximum egg recovery rate was 25.04% from sandy soil at a concentration of 500 eggs/25 g soil while with zinc sulphate it was 13.88% also from sandy soil and concentration of 500 eggs/25 g soil. While the number of eggs recovered increased with soil egg concentration, the percentage of eggs recovered is inversely proportional to egg concentration. The number of eggs recovered with sodium nitrate was significantly higher than with zinc sulphate solution in the three soil types.


2009 ◽  
Vol 57 (8) ◽  
pp. 629 ◽  
Author(s):  
Timothy J. Curran ◽  
Peter J. Clarke ◽  
Nigel W. M. Warwick

The occurrence of dry rainforest in climates considered drier than the recognised limit for rainforest has been explained by the edaphic compensation hypothesis, which proposed that finer-textured soils facilitate the occurrence of rainforest at climatic extremes. We tested this by examining the effect of soil type on the water relations and plant traits of four dry rainforest species, during a severe drought and subsequent non-drought periods. We predicted plants growing in sandy soils would exhibit higher levels of water stress (lower predawn water potential and stomatal conductance) and possess morphological and physiological traits that more typically reflect drought resistance (late leaf fall in deciduous species, low specific leaf area, vertical leaf angles and stomata that close at low water potential) than those growing in loam soils. During drought, levels of water stress were similar across soil types, while post-drought plants on sandy soils were less stressed. Soil type did not cause shifts in drought tolerance traits, suggesting there has been no ecotypic differentiation of dry rainforest species across soil types for these traits. Hence, we found no support for the edaphic compensation hypothesis in adult plants; future studies should consider other life-cycle stages, such as seedlings.


1992 ◽  
Vol 19 (6) ◽  
pp. 601 ◽  
Author(s):  
CL Petrie ◽  
AE Hall

Pearl millet [Penniseturn americanum (L.) Leeke] consistently develops lower predawn leaf water potentials than cowpea [Vigna unguiculata (L.) Walp.] when plants are subjected to progressive soil drying, even when they are grown as intercrops in the same pot. Lack of equilibrium in water potential during the predawn, within the plants and between plants and soil, was studied as a possible explanation for this difference. Experiments were conducted in a glasshouse in pots containing an artificial rooting medium which had a high water-holding capacity and was easy to separate from roots. Leaf and root predawn xylem water potentials were measured with a pressure chamber. In cowpea, leaf water potential (ΨL) values during the dry treatment were similar to values of root water potential (ΨR), indicating an approximate equilibrium within the plants. In millet, measurements were made on plants grown in both large and small pots. With large pots, ΨL and ΨR values in millet were similar, but with small pots, predawn ΨL was lower than ΨR. When the surfaces of these small pots were covered with evaporation barriers, however, no significant differences developed between ΨL and ΨR at predawn during soil drying, indicating an approximate equilibrium within millet. During the early stages of the dry treatment, leaf surface conductances measured at predawn indicated that significant water flux occurred at night from the leaves of both cowpea and millet. Leaf surface conductances declined to negligible levels as the dry treatment progressed, however, and night-time fluxes of water from leaves cannot explain the significant difference in predawn ΨL that developed between cowpea and millet. In order to determine whether the lower predawn ΨL in millet was due to a resistance to water uptake at the root surface, an osmoticum (- 0.5 MPa mannitol solution) was applied to pots of cowpea and millet intercrops after substantial differences in predawn ΨL had developed, and ΨL was measured. Measurements taken 9 h later indicated that predawn ΨL had recovered in millet, and the values of ΨL in millet and cowpea after mannitol treatment were similar to the osmotic potential of the mannitol solution. These results suggest that the lower predawn ΨL in millet than in cowpea under drought is due to the development of a substantial soil resistance to water movement to the root surfaces of millet.


1974 ◽  
Vol 46 (3) ◽  
pp. 277-288
Author(s):  
Asbjørn Sorteberg

An account is given of a pot experiment comprising all combinations of 5 heavy metals (cadmium, cobalt, lead, mercury and nickel), 3 rates of each metal (0, 50 and 250 mg/pot), 2 rates of lime, and 3 types of soil (clay soil, peat soil, and sandy soil). Crop yields of grain and straw are given in Table 2. Low addition of the metal (50 mg/pot) has had slight or no effect on the yield size. The high rate of metal (250 mg/ pot) of some of the metals has induced definite to heavy yield reductions. Nickel has led to a heavy yield decrease in all soil series both in grain and straw afterlight liming. The yield reduction is to a certain extent or completely eliminated after heavier liming. Mercury has induced a near complete crop failure in the sandy soil series at both lime rates. Some yield reduction is obvious also in the other soil series, in clay soil only after light liming. Cadmium has reduced the straw yields in peat soil after both lime rates. Clay soil shows grain yield reduction at heaviest liming, while no yield reduction is detectable in the sandy soil. Cobalt has induced some degree of yield reduction in all soil types, most of all in clay soil after light liming. Lead has had no effect on the yield size. The heavy metal content in the crop is presented in Table 3. Apart from lead, the relative content increases very heavily with increased metal application. The content at times proves essentially higher in the crop from peat soil and sandy soil than in crop from clay soil. The content of cadmium, nickel and cobalt is lower at heavy liming compared to light liming. This is particularly characteristic of the crop from clay soil and sandy soil. The effect of heavier liming on the mercury and lead uptake is equivocal. For nickel, the relative content is essentially higher in the grain than in straw. The content of other metals is higher in the straw. The lead content in particular is much higher in straw than in the grain. In addition to the crop experiment, all treatments have included one parallel pot without plants. At the harvesting time, samples were taken from these pots for chemical analysis. The heavy metal content was determined after extraction by an AL-solution (Table 4). Wide variations appear between metals and soil types with regard to the recovered amounts of applied metal. Mercury shows a characteristically low AL-soluble recovery, only 1 to 2 per cent at the highest application rate. Also of lead, only a small amount of the applied substance exists as AL-soluble. With regard to the remaining metals, nearly all have been recovered as AL-soluble by a heavy application of cadmium to sandy soil at light liming. In other cases the percentage recovery falls within the 20—70 range, the lower figures often pertaining to clay soil and the higher ones to peat soil. A description of plants influenced by retarded growth, and symptoms of toxicity, are given.


2017 ◽  
Vol 22 (3) ◽  
pp. 233 ◽  
Author(s):  
B.S. Ismail ◽  
A.O.S. Enoma

A study of the degradation of endosulfan (6, 7, 8, 9, 10, 10-hexachloro – 1, 5, 5a, 6, 9, 9a –hexahydro – 6, 9- methano – 2, 4, 3 – benzodioxanthiepin 3 – oxide) in Malaysian sandy loam and clay soils was carried out using a radioisotopic technique under laboratory conditions. It was demonstrated that endosulfan possessed long half-lives of 433, 495 and 462 days in aerobic sandy loam, aerobic clay and anaerobic clay soils respectively. Endosulfan degrades faster in non-sterile than in sterile soils. This study indicates that microorganisms are involved in the degradation of endosulfan. In general, degradation of the pesticide was relatively higher in the clay soil than in the sandy soil. Apart from the parent compounds, α- and β-isomers, the degradation products include endosulfan sulphate and three minor unidentified products. 


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