Recovery of soil physical properties by green manure, liming, gypsum and pasture and spontaneous native species¹

Inadequate usage can degrade natural resources, particularly soils. More attention has been paid to practices aiming at the recovery of degraded soils in the last years, e.g, the use of organic fertilizers, liming and introduction of species adapted to adverse conditions. The purpose of this study was therefore to investigate the recovery of physical properties of a Red Latosol (Oxisol) degraded by the construction of a hydroelectric power station. In the study area, a soil layer about 8m thick had been withdrawn by heavy machines leading not only to soil compaction, but resulting in high-degree degradation. The experiment was arranged in a completely randomized design with nine treatments and four replications. The treatments consisted of: 1- soil mobilization by tilling (to ensure the effect of mechanical mobilization in all treatments) without planting, but growth of spontaneous vegetation; 2- Black velvet bean (Stizolobium aterrimum Piper & Tracy); 3- Pigeonpea (Cajanus cajan (L.) DC); 4- Liming + black velvet bean; 5-Liming + pigeonpea until 1994, when replaced by jack bean (Canavalia ensiformis); 6- Liming + gypsum + black velvet bean; 7- Liming + gypsum + pigeonpea until 1994, when replaced by jack bean; and two controls as reference: 8- Native Cerrado vegetation and 9- bare soil (no tilling and no planting), left under natural conditions and in this situation, without spontaneous vegetation. In treatments 1 through 7, the soil was tilled. Treatments were installed in 1992 and left unmanaged for seven years, until brachiaria (Brachiaria decumbens) was planted in all plots in 1999. Seventeen years after implantation, the properties soil macroporosity, microporosity, total porosity, bulk density and aggregate stability were assessed in the previously described treatments in the soil layers 0.00-0.10; 0.10-0.20 and 0.20-0.40 m, and soil Penetration Resistance and soil moisture in 0.00-0.15 and 0.15-0.30 m. The plants were evaluated for: brachiaria dry matter and spontaneous growth of native tree species in the plots as of 2006. Results were analyzed by variance analysis and Tukey´s test at 5 % for mean comparison. In all treatments, except for the bare soil (no recovery measures), ongoing recovery of the degraded soil physical properties was observed. Macroporosity, soil bulk density and total porosity were good soil quality indicators. The occurrence of spontaneous native species indicated the soil recovery process. The best adapted species was Machaerium acutifolium Vogel, with the largest number of plants and most advanced development; the dry matter production of B. decumbens in recovering soil was similar to normal conditions, evidencing soil recovery.

[Illustrations de Le Temple de Gnide] / Le Mire Noël, grav. ; Montesquieu, aut. du texte

Comprend : [Pl. en reg. p.1. Premier chant : Vénus et Vulcain, sur le lit nuptial, devant l'assemblée des Dieux et des nymphes (dont Mercure et Zeus).] Sa robe fuit ses genoux, la toile vole... [Cote : 4 ° Z Don 205 (39)/Microfilm R 122407] ; [Pl. en reg. p.25. Second chant : une coquette, venue à Gnide, reçoit l'oracle de Vénus. ] Tu mourras accablée de refus et de mépris. [Cote : 4 ° Z Don 205 (39)/Microfilm R 122407] ; [Pl. en reg. p.31. Troisième chant : Vénus et les trois Grâces couronnent la beauté de Thémire.] Elle appella les Grâces : Allez la couronner... [Cote : 4 ° Z Don 205 (39)/Microfilm R 122407] ; [Pl. en reg. p.45. Quatrième chant : Thémire et son amant.] Une nuit que j'étois dans cet état tranquille... [Cote : 4 ° Z Don 205 (39)/Microfilm R 122407] ; [Pl. en reg. p.61. Cinquième chant : Aristée et Camille.] Je sens couler mes larmes... [Cote : 4 ° Z Don 205 (39)/Microfilm R 122407] ; [Pl. en reg. p.73. Sixième chant : la Fureur jette un serpent dans le coeur de l'amant de Thémire.] Elle détacha un de ses serpents. .. [Cote : 4 ° Z Don 205 (39)/Microfilm R 122407] ; [Pl. en reg. p.87. Septième chant : l'Amour se cache sous les jupes de Thémire.] Il se cacaha sous ses genoux, je le suivis... [Cote : 4 ° Z Don 205 (39)/Microfilm R 122407] ; [Pl. en reg. p.99 : Céphise coupe les aîles de l'Amour.] Elle coupa le sommet des aîles de l'Amour... [Cote : 4 ° Z Don 205 (39)/Microfilm R 122407] ; [Pl. en reg. p.102 : Jupiter envoie Cupidon auprès de Vénus pour que l'amour de la déesse fasse repousser les aîles de l'Amour.] La chaleur va les faire renaître... [Cote : 4 ° Z Don 205 (39)/Microfilm R 122407]

Residual effect of soil tillage on water erosion from a Typic Paleudalf under long-term no-tillage and cropping systems

Soil erosion is one of the chief causes of agricultural land degradation. Practices of conservation agriculture, such as no-tillage and cover crops, are the key strategies of soil erosion control. In a long-term experiment on a Typic Paleudalf, we evaluated the temporal changes of soil loss and water runoff rates promoted by the transition from conventional to no-tillage systems in the treatments: bare soil (BS); grassland (GL); winter fallow (WF); intercrop maize and velvet bean (M+VB); intercrop maize and jack bean (M+JB); forage radish as winter cover crop (FR); and winter cover crop consortium ryegrass - common vetch (RG+CV). Intensive soil tillage induced higher soil losses and water runoff rates; these effects persisted for up to three years after the adoption of no-tillage. The planting of cover crops resulted in a faster decrease of soil and water loss rates in the first years after conversion from conventional to no-tillage than to winter fallow. The association of no-tillage with cover crops promoted progressive soil stabilization; after three years, soil losses were similar and water runoff was lower than from grassland soil. In the treatments of cropping systems with cover crops, soil losses were reduced by 99.7 and 66.7 %, compared to bare soil and winter fallow, while the water losses were reduced by 96.8 and 71.8 % in relation to the same treatments, respectively.

Changes in Soil Organic Carbon Fractions in Response to Cover Crops in an Orange Orchard

ABSTRACT The cultivation of cover crops intercropped with fruit trees is an alternative to maintain mulch cover between plant rows and increase soil organic carbon (C) stocks. The objective of this study was to evaluate changes in soil total organic C content and labile organic matter fractions in response to cover crop cultivation in an orange orchard. The experiment was performed in the state of Bahia, in a citrus orchard with cultivar ‘Pera’ orange (Citrus sinensis) at a spacing of 6 × 4 m. A randomized complete block design with three replications was used. The following species were used as cover crops: Brachiaria (Brachiaria decumbes) – BRAQ, pearl millet (Pennisetum glaucum) – MIL, jack bean (Canavalia ensiformis) – JB, blend (50 % each) of jack bean + millet (JB/MIL), and spontaneous vegetation (SPV). The cover crops were broadcast-seeded between the rows of orange trees and mechanically mowed after flowering. Soil sampling at depths of 0.00-0.10, 0.10-0.20, and 0.20-0.40 m was performed in small soil trenches. The total soil organic C (SOC) content, light fraction (LF), and the particulate organic C (POC), and oxidizable organic C fractions were estimated. Total soil organic C content was not significantly changed by the cover crops, indicating low sensitivity in reacting to recent changes in soil organic matter due to management practices. Grasses enabled a greater accumulation of SOC stocks in 0.00-0.40 m compared to all other treatments. Jack bean cultivation increased LF and the most labile oxidizable organic C fraction (F1) in the soil surface and the deepest layer tested. Cover crop cultivation increased labile C in the 0.00-0.10 m layer, which can enhance soil microbial activity and nutrient absorption by the citrus trees. The fractions LF and F1 may be suitable indicators for monitoring changes in soil organic matter content due to changes in soil management practices.

Las Ideas de 'Weltbürgertum' y 'Ewige Friede' en la Metafísica de las costumbres

Se estudian en este artículo las ideas de "paz perpetua" y "ciudadanía universal"según Kant, quien define su conjunto como el "supremo bien político" y la cumbre de la Doctrina del derecho. El propósito principal de esta investigación es reconstruir todo elcomplejo conjunto de "paz perpetua" y "comunidad universal" a través de los textos de La Metafisica de las costumbres. El segundo propósito es tratar de resolver las ambivalenciascognitivas de tales ideas en conexión con su desarrollo práctico y explicar las dudas y vacilaciones de Kant cuando en la Doctrina del derecho ha de definir las consecuenciasúltimas de tal conjunción. Para reconstruir fielmente el pensamiento kantiano, seguimos un método genético al investigar y al exponer.

Frequent accesses to totally implanted vascular ports in pediatric oncology patients are associated with higher infection rates.

PURPOSE: Totally implanted vascular (TIVA) ports are used in children for repeated blood samples or intravenous treatments. We have recently published a prospective evaluation of surgical incidents and early complications associated with these devices. This work is the final part of the same study, assessing late complications over a follow-up of 2 yrs. METHODS: From January 2006 to January 2008, children older than 1 yr of age with a diagnosis of solid or blood cell malignancy were included. Insertion technique and care of the device were standardized. Every manipulation was prospectively recorded by specialized nurses. Obstruction was documented clinically. When bacteremia was suspected, routine central and peripheral blood cultures were drawn. RESULTS: Forty-five consecutive patients were enrolled in the study. Mean age at the time of the procedure was 8.5 yrs. There was no catheter-related infection within the first 4 weeks post-surgery. No device had to be removed because of infection or obstruction during follow-up. Frequent accesses to the port (=3 per day over a 10-day period) were associated with an 8-fold risk of infection. CONCLUSION: Insertion and use of TIVA devices were frequently associated with complications. No device had to be removed because of infection or obstruction over the follow-up period, although no prophylactic antibiotic agent was used. Restrictive use of antibiotics may prevent opportunistic infection. Frequent access to the device was significantly associated with line infection (odds ratio=8.43). No risk factor was identified for obstruction which occurred at a rate of 5.3 per 10,000 accesses.

Legislación sanitaria marítima en Catalunya: 1717-1752

Aquesta publicació la formen les transcripcions d'unes disposicions legals establertes entre 1717 i 1752 pels guanyadors de la guerra de Successió (1702-1714). Es tracta doncs de legislació sanitària dictada específicament per al litoral marítim català. També trobem un estudi previ de l'autor sobre la situació política i social de la Catalunya i especialment de Barcelona després de la derrota de mans de les tropes de Felip V.