No-tillage implementation: Analyzis on water-based sediment flow in the Marombas River, Brazil

ABSTRACT Water erosion is influenced by climate, soil, soil cover and soil conservation practices. These factors can be modified by natural (especially climate) and/or anthropogenic (especially soil, soil cover and conservation practices) actions. The relief factor also influences the water erosion and can also be partially modified by anthropic action. This study aimed to evaluate the impact of anthropogenic action due to the introduction of soil crop in no-tillage system on water erosion, and on the consequent flow of sediments in the water. The study was carried out in the Marombas river basin with an area of 3,939 km², using the Soil Water Assessment Tools (SWAT) model. The calibration and validation of the model for sediment production was carried out with a historical series of synthetic data. The data from this series were estimated by linear regression from sediment value load and the average daily flow obtained punctually in the basin’s outlet. The SWAT model was calibrated on a daily scale with data from 1979 to 1989 and was validated with data from 1994 and 1997. The SWAT model was suitable to represent the average daily flow and sediment flow in the Marombas watershed. The hypothesis of reduced sediment production with increasing soil crop in no-tillage system was accepted.

Traditional Water Conservation Techniques in India

Water conservation is a practice needed for survival. In India, various techniques are used to save water, which are practical and climate-responsive. From the age of the Indus valley civilization, till today many practices are seen in different parts of India. The traditional practices used for conserving water and even cooling buildings in ancient times. Forts surrounded water bodies for protection from enemies. Indians continue to build structures to catch and store the monsoon rains. Some unique water conservation techniques are still practiced in India and are efficient. These are sometimes better than the presentday water-saving techniques. The paper summarizes the transformation over the years in the construction and advancements of water conservation practices in India. In dry regions, these practices have helped people survive tough times. Keywords: Rain water harvesting, Storage, Tanks, Traditional methods, Water conservation

Root mass vertical distribution of perennial cool-season grasses grown in pure or mixed swards

ABSTRACT: In this study we tested whether the root biomass of mixtures composed by grass species is greater than their respective monocultures. The treatments were monocultures of Arrhenatherum elatius, Festuca arundinacea, Dactylis glomerata, and a mixture of them, cultivated in a rich-soil environment. Root biomass was evaluated on a single evaluation per season at three soil depths (0-5, 5-10, and 10-20 cm). Mixed swards presented the greatest root biomass, and this was explained by a greater concentration in the topsoil layer (0-5 cm). These findings reinforce the need for permanent soil conservation practices to not jeopardize the benefits of the more abundant root biomass reported in the mixed swards.

Severity of clubroot in kale related to management practices and soil attributes

ABSTRACT: Clubroot disease, caused by Plasmodiophora brassicae, limits the production of Brassica spp. worldwide. Little is known about the factors related to the development of the disease in kale (Brassica oleracea var. acephala) plants and in crops in mountainous areas under tropical conditions. This study examined the severity of clubroot in kale crops as well as identify potential flaws in management and the soil and relief factors related to its occurrence. The study was conducted in 24 kale fields in the mountainous region of Rio de Janeiro (Brazil). Soil and kale growth management practices adopted in the region were identified and samples of soil and plants were collected. Subsequently, soil and relief attributes, disease severity, biomass and nutrient and Al contents and accumulation in the plants were determined. There was a high spread of the pathogen in the areas. Inappropriate and recurrent practices in the region were detected, e.g., sequential cultivation of host species, low adoption of soil fertility analysis and liming and conservation practices, and community use of agricultural machinery and implements without prior cleaning. The disease was associated with more acidic soils, subject to greater water accumulation and with high levels of Al3+ as well as with higher Al contents and accumulation in the roots. Management practices must be adopted in the region to reduce the potential inoculum of P. brassicae and to increase soil fertility.

Over and Over and Over Again

Over the last twenty years, reenactment has been appropriated by both contemporary artistic production and art-theoretical discourse, becoming a distinctive strategy to engage with history and memory. As a critical act of repetition, which is never neutral in reactualizing the past, it has established unconventional modes of historicization and narration. Collecting work by artists, scholars, curators, and museum administrators, the volume investigates reenactment's potential for a (re)activation of layered temporal experiences, and its value as an ongoing interpretative and political gesture performed in the present with an eye to the future. Its contributions discuss the mobilization of archives in the struggle for inclusiveness and cultural revisionism; the role of the body in the presentification and rehabilitation of past events and (impermanent) objects; the question of authenticity and originality in artistic practice, art history, as well as in museum collections and conservation practices.