RESIDUAL EFFECTS OF COMPACTION AND TILLAGE ON THE SOIL PROFILE CHARACTERISTICS OF A CLAY-TEXTURED SOIL

Detailed soil profile descriptions were made to assess the residual effect of compaction and tillage treatments applied 10 yr ago on a Ste-Rosalie clay. The treatments applied consisted of five passes at a contact pressure of 61.8 kPa with no tillage, 15 passes of 61.8 kPa with chiselling, moldboard plowing, no tillage, subsoiling, and a control. The results were analyzed using nonparametric statistics. The untilled plots that received 15 wheel passes showed mottling that was more abundant and closer to the surface than the other plots while the subsoiled plots had a finer, less abundant and deeper mottling than the other plots. Peds in the Ae horizon were finer in the subsoiled and chiselled plots and coarser in the untilled plots and conventionally tilled plots that received 15 vehicle passes. It appears from this work that the effect of compaction is very persistent in clay soil and that subsoiling followed by reduced traffic can have a long-term effect on soil structure. Key words: Compaction, tillage, profile descriptions, clay soil

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Polyacrilonytrile versus Cuprophan Membranes for Hemodialysis: Evaluation of Efficacy and Biocompatibility by Platelet Aggregation Studies

The International Journal of Artificial Organs ◽

10.1177/039139888100400505 ◽

1981 ◽

Vol 4 (5) ◽

pp. 218-222 ◽

Cited By ~ 16

Author(s):

M. Berrettini ◽

U. Buoncristiani ◽

P. Parise ◽

E. Ballatori ◽

G.G. Nenci

Keyword(s):

Platelet Count ◽

Platelet Aggregation ◽

Term Effect ◽

The Other ◽

Long Term Effect ◽

Short And Long Term ◽

Extracorporeal Dialysis ◽

Uremic Patients

The short- and long-term effect of hemodialysis with two different membranes — cuprophan and polyacrilonytrile — on platelet aggregation has been investigated in 12 uremic patients undergoing extracorporeal dialysis, passing from one treatment to the other. Cuprophan membranes failed to correct the defective platelet aggregation of uremia, and their thrombogenicity was documented by a fall in platelet count and further impairment of platelet aggregation during dialysis. On the contrary, polyacrilonitryle membranes showed the capacity to correct completely but transiently the platelet aggregation, without changes in platelet count. The results indicate that polyacrilonytrile membranes show a better biocompatibility toward platelets than cuprophan membranes.

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Phosphorus and root distribution and corn growth as related to long-term tillage systems and fertilizer placement

Revista Brasileira de Ciência do Solo ◽

10.1590/s0100-06832009000500017 ◽

2009 ◽

Vol 33 (5) ◽

pp. 1237-1247 ◽

Cited By ~ 13

Author(s):

Sérgio Ely Valadão Gigante de Andrade Costa ◽

Edicarlos Damaceno de Souza ◽

Ibanor Anghinoni ◽

João Paulo Cassol Flores ◽

Eduardo Giacomelli Cao ◽

...

Keyword(s):

Soil Profile ◽

Root Distribution ◽

Grain Filling ◽

Crop Productivity ◽

Soil Tillage ◽

No Tillage ◽

Fertilizer Placement ◽

Tillage Systems ◽

P Utilization

Soil and fertilizer management during cultivation can affect crop productivity and profitability. Long-term experiments are therefore necessary to determine the dynamics of nutrient and root distribution as related to soil profile, as well as the effects on nutrient uptake and crop growth. An 18-year experiment was conducted at the Federal University of Rio Grande do Sul State (UFRGS), in Eldorado do Sul, Brazil, on Rhodic Paleudult soil. Black oat and vetch were planted in the winter and corn in the summer. The soil management methods were conventional, involving no-tillage and strip tillage techniques and broadcast, row-and strip-applied fertilizer placement (triple superphosphate). Available P (Mehlich-1) and root distribution were determined in soil monoliths during the corn grain filling period. Corn shoot dry matter production and P accumulation during the 2006/2007 growing season were determined and the efficiency of P utilization calculated. Regardless of the degree of soil mobilization, P and roots were accumulated in the fertilized zone with time, mainly in the surface layer (0-10 cm). Root distribution followed P distribution for all tillage systems and fertilizer treatments. Under no-tillage, independent of the fertilizer placement, the corn plants developed more roots than in the other tillage systems. Although soil tillage systems and fertilizer treatments affected P and root distribution throughout the soil profile, as well as P absorption and corn growth, the efficiency of P utilization was not affected.

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Phosphorus Availability for Irrigated Rice Cultivated Under No-Tillage and Different Phosphate Sources

Journal of Agricultural Science ◽

10.5539/jas.v10n5p276 ◽

2018 ◽

Vol 10 (5) ◽

pp. 276

Author(s):

Magali De Ávila Fortes ◽

Rogério Oliveira de Sousa ◽

Algenor da Silva Gomes ◽

Fabiana Schmidt ◽

Walkyria Bueno Scivittaro ◽

...

Keyword(s):

Residual Effect ◽

Rice Crop ◽

Residual Effects ◽

P Availability ◽

No Tillage ◽

Irrigated Rice ◽

Soil P ◽

Phosphate Fertilization ◽

Tillage System ◽

Yield Responses

The objective of this work was to evaluate the response of irrigated rice to phosphate fertilization using triple superphosphate (TSP) and Arad phosphate rock (APR), and the phosphate residual effects of upland crops in no-tillage system on the following rice crop. Also, it aimed to evaluate the efficiency of Mehlich-1 and anion exchange resin as soil P extractors. Two experiments were conducted in Albaqualf soil under irrigated conditions in the southern region of Rio Grande do Sul State. The experiments were designed as random blocks with four replications and the treatments were displayed as a 2 × 2 factorial (TSP and APR, with and without annual P application as TSP). No yield responses to phosphate were observed. Phosphate fertilization performed on upland crops (maize and soybeans) presented a residual effect on the rice crop even after four years of consecutive cropping under no-tillage. The extractors Mehlich-1 and AER were equally efficient in the evaluation of P availability for the rice crop. P content values obtained by both methods did show a significant correlation with accumulated plant P. The APR presents a similar performance as the TSP in regard to phosphate nutrition in irrigated rice when rotated with upland crops under no-tillage system.

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OBSERVATIONS ON SUCCESSIVE PRO-OESTROUS LH SURGES IN INDIVIDUAL 4-DAY CYCLING AND POST-PSEUDOPREGNANT RATS

Acta Endocrinologica ◽

10.1530/acta.0.0880274 ◽

1978 ◽

Vol 88 (2) ◽

pp. 274-284 ◽

Cited By ~ 2

Author(s):

Alberto J. Carrillo ◽

Charles H. Sawyer

Keyword(s):

Mechanical Stimulation ◽

Term Effect ◽

Oestrous Cycle ◽

The Other ◽

Peak Amplitude ◽

Lh Surge ◽

Long Term Effect ◽

The Mean ◽

Stimulation Of

ABSTRACT The internal variations (i. e. in timing, duration and amplitude) of the LH surge mechanism within individual rats were examined by monitoring from 3 to 7 successive pro-oestrous LH surges in each of 5 regular 4-day cycling rats fitted with chronic intravenous cannulas. On each successive pro-oestrus blood was collected (0.5–0.6 ml hourly from 14.00–21.00) for radioimmunoassay of LH. The surgery of cannulation had no long-term effect on the regularity of the oestrous cycle. Two rats did, however, show briefly irregular cycles, including one with a 9-day period of anoestrus (pseudopregnancy). In three of the five rats successive pro-oestrous plasma LH curves (4 in one and 3 each in the other two) were internally very consistent in timing, shape and amplitude, However, between each 2 of these 3 animals there were distinct differences in the LH secretory patterns, by as much as 2 h in timing of the onset of the surge and its peak amplitude. The first two surges of the other two rats were atypical of their subsequent surges, which were mostly consistent in timing and amplitude. The pro-oestrous LH surge following the 9-day period of anoestrus was advanced by 2 h and elevated to twice the mean peak amplitude of the cyclic LH surges in that rat. Subsequently, post-PSP surges were studied in rats made pseudopregnant by mechanical stimulation of the cervix. In all cases the immediate post-PSP surge occurred earlier in the afternoon and with a greater peak amplitude than the subsequent cyclic LH surge in the same rat.

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THE EVALUATION OF THE RESIDUAL EFFECT OF FERTILIZER IN LONG-TERM FERTILITY PLOTS: I. POTASSIUM

Canadian Journal of Soil Science ◽

10.4141/cjss63-028 ◽

1963 ◽

Vol 43 (2) ◽

pp. 229-234 ◽

Cited By ~ 2

Author(s):

A. A. MacLean ◽

J. J. Doyle

Keyword(s):

Nitric Acid ◽

Cation Exchange ◽

Cation Exchange Capacity ◽

Surface Soil ◽

Sandy Loam ◽

Residual Effect ◽

Exchange Capacity ◽

Residual Effects ◽

Intensive Cropping

Residual effects of long-term annual applications of fertilizer potassium on the potassium status of an acid sandy loam Podzol were investigated, in a greenhouse experiment. Potassium accumulated in the surface soil in a form readily available to plants.On plots with higher cation exchange capacities, resulting from manurial treatments, there was no evidence to indicate leaching below 15 inches. On plots where cation exchange capacity was not increased by treatment, a higher percentage potassium saturation at greater depths indicates that leaching of potassium had occurred to a depth of 21 inches. An increased concentration of nitric acid-soluble potassium at greater depths suggests that some of the leached potassium has been converted to the non-exchangeable form.Accumulation in the surface soil was sufficient to supply most of the potassium requirement of ladino clover under conditions of intensive cropping. The results suggest that exchangeable and nitric acid-soluble potassium are reliable criteria of available potassium.

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Toxicities and Residual Effect of Spinosad and Alpha-Cypermethrin-Based Baits to Replace Malathion for Ceratitis capitata (Diptera: Tephritidae) Control

Journal of Economic Entomology ◽

10.1093/jee/toz104 ◽

2019 ◽

Vol 112 (4) ◽

pp. 1798-1804 ◽

Cited By ~ 3

Author(s):

Cléber Antonio Baronio ◽

Inana Xavier Schutze ◽

Marcelo Zanelato Nunes ◽

Daniel Bernardi ◽

Ruben Machota ◽

...

Keyword(s):

Ceratitis Capitata ◽

Insect Pest ◽

Residual Effect ◽

Adult Mortality ◽

The Other ◽

Residual Effects ◽

Sugarcane Molasses ◽

Hydrolyzed Protein ◽

Simulated Rain ◽

Food Lures

Abstract Ceratitis capitata (Wiedemann, 1824) is the main insect pest of fruits worldwide. The objective of this study was to evaluate the toxicity and residual effects of the ready-to-use toxic baits Success 0.02CB (0.24 g of active ingredient [a.i.] per liter of spinosad) and Gelsura (6 g of a.i./liter of alpha-cypermethrin) and to compare them with other food lures containing spinosad and malathion mixed with hydrolyzed protein (Biofruit 5% and Flyral 1.25%), Anamed without dilution or sugarcane molasses (7%) against adult C. capitata in laboratory and greenhouse trials. Ceratitis capitata adults were highly susceptible to all toxic bait formulations (mortality > 80%) until 96 h after exposure. The lowest LT50 (hours) of toxic baits were 2.32 (Gelsura at 4,000 mg/liter), 4.26 (Gelsura at 2,000 mg/liter), 4.28 (Anamed + malathion) and 4.89 (sugarcane molasses + malathion), while formulations containing spinosad (Biofruit, Flyral, Anamed and Success 0.02CB) showed LT50 of approximately 11 h. Without rain, Gelsura (2,000 mg/liter) and all spinosad formulations provided mortality superior to 80% 14 d after application. Gelsura and Anamed + spinosad showed higher resistance to a 5-mm simulated rain, similar to Anamed + malathion, while the other formulations had its efficacy decreased. All toxic baits were effective on adult C. capitata in residual experiments without rain while Anamed + spinosad caused high adult mortality after 5 to 25 mm rains. Gelsura and Anamed + spinosad can be used to replace toxic baits containing malathion for C. capitata population management.

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Evaluating the stability and evolution of a proposed post mining landform.

10.5194/egusphere-egu21-8569 ◽

2021 ◽

Author(s):

Welivitiyage Don Dimuth Prasad Welivitiya ◽

Garry Willgoose ◽

Gregory Hancock

Keyword(s):

Cross Sections ◽

Soil Profile ◽

Evolution Model ◽

Short Term ◽

Landform Evolution ◽

Erosion Rates ◽

Denudation Rates ◽

Land Denudation ◽

Profile Characteristics

Evaluating the future stability and land denudation rates of natural or anthropogenic landforms is paramount for sustainable land use practices. Landform evolution models can be powerful tools in this endeavour.&#160; In this study we used the well-established landform evolution model SIBERIA and the newly developed coupled soilscape-landform evolution model SSSPAM to simulate the evolution of a proposed post mining landform. SIBERIA uses a cellular digital elevation model to simulate annual average fluvial and diffusive erosion on landforms using annual average precipitation. However it does not simulate the soil profile evolution on the evolving landform. The new SSSPAM coupled soilscape-landform evolution model has the ability to assess the overall erosion rates of catchment scale landforms either using short term precipitation events, variable precipitation or time averaged precipitation rates. In addition, SSSPAM is able to simulate the evolution of the soil profile of the evolving landform using pedogenetic processes such as physical weathering and armouring.&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; To assess the reliability of SSSPAM, model predictions at 100 and 10000 years were compared with SIBERIA predictions at the same times. During the long term (10000yr) simulation the effect of armouring and weathering on the landform evolution was also assessed. The results obtained from these different simulations were compared and contrasted. Comparison of the short term simulations revealed that SSSPAM results compare well with the simulation results of the more established SIBERIA model. Long term simulation showed that SSSPAM simulation results also compares well with SIBERIA simulations while the erosion rates predicted by both models are close to the land denudation rates measured in the field. The soil profile characteristics and channel forms simulated by SSSPAM long term simulations were examined using several landform cross-sections. This analyses revealed that SSSPAM produces deep incised channels with very low soil thickness in upper reaches of the catchment and shallow channels with relatively thick soil layers in the lower reaches of the catchment. These SSSPAM simulated channels match well with the channel forms and distribution of bedrock channels and alluvial channels observed in the field. The analysis of the catchment cross-sections also showed that SSSPAM is capable of reproducing complex subsurface soil evolution and stratification and spatial variability of soil profile characteristics typically observed in the field.

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Long-term effects of tillage intensity on the distribution of microbial biomass and activity in four arable field-sites across Europe

10.5194/egusphere-egu2020-9043 ◽

2020 ◽

Author(s):

Ilka Schmoock ◽

Deborah Linsler ◽

Mignon Sandor ◽

Rainer Georg Joergensen ◽

Martin Potthoff

Keyword(s):

Microbial Biomass ◽

Soil Quality ◽

Soil Profile ◽

Soil Microbial Biomass ◽

Reduced Tillage ◽

No Tillage ◽

Tillage Systems ◽

Minimum Tillage ◽

Soil Microbial

Over the last decades, reduced tillage became more and more important as a suitable soil management practice. Moreover, reduced tillage is expected to promote a healthy and active soil life as a feature of sustainable agricultural. The determination of soil microbial biomass and microbial indices are suitable indicators for estimating soil quality. This study follows a regional approach and focusses at four different countries with varying environmental conditions at long-term experimental field-sites (LTE&#180;s) across Europe. Soil microbial biomass carbon (SMB-C), the metabolic quotient (qCO2) and the ratio of SMB-C to soil organic carbon (SOC) were measured as microbial properties.Our contribution to the ongoing discussion of the effectiveness of non-conventional tillage systems is (i) the comparison between conventional ploughing (CT) and minimum tillage (MT), (ii) the comparison of inversion vs. not inversion tillage at the same working depth, (iii) the comparison of ploughing vs. no-tillage (NT), (iv) the comparison between reduced tillage systems with each other (MT vs. NT).We found a significant difference of SMB-C for CT and MT between 0 and 10 cm in Germany and Sweden, but no difference between tillage treatments for the sampled soil profile (0-30 cm). We highlight that tillage changed the vertical distribution of SMB-C, showing similar values among soil depths under CT and a depth gradient with decreasing values for MT.The comparison of inversion vs. not inversion tillage at the same working depth in Romania showed no differences between CT and MT at all. This suggests that humus-rich soils seem to be more resistant to tillage-related disturbances. The working depth might have a greater impact for both, inversion and non-inversion tillage than the type of the tillage system itself.For the comparison of CT and NT, we used the field-sites in Spain and Sweden. In Spain, NT was clearly of advantage for microbial biomass and activity, compared to CT. This was true for the whole sampled soil profile (0-30&#160;cm) whereas in Sweden differences could only be detected between SMB-C levels in two soil depths. Our results indicate that the effect of tillage seems to be smaller in cold-temperate areas.Comparing MT and NT in Sweden, we found no difference in SMB-C between these two forms of conservation tillage, neither in the first centimeters, nor in the whole sampled profile. Consequently, minimum tillage seems to be an alternative in cold and moist regions if no-tillage is not possible to apply without reducing soil quality or crop yields.We conclude that even if minimum and no-tillage are generally beneficial for microorganisms, there is a big variance between the different forms of reduced tillage systems. Thus, statements cannot be made across different soils and machine types, but have to be made on a regional scale.&#160;

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