Trifluralin Leaching in Soils Cultivated With Sugarcane Irrigated by Sub-Surface Drip System

Abstract

In order to assess the movement of trifluralin in soils, used as root intrusion inhibitor in subsurface drip irrigation system (SDI), its concentration at effluent from lysimeters was measured. The lysimeters with sugarcane (Sacharum officinarum L.) under natural weather conditions and supplementary irrigation were filled with two Oxisols and an Ultisol. Three lysimeters with undisturbed soil were used as replicates for each treatment; the columns were one meter in diameter and 45cm deep. The SDI system consisted of drippers installed at 20cm depth, with 10.5mm internal diameter tubing with 6 emitters per lysimeter spaced 50cm between them. A moisture sensor was installed in each lysimeter to monitor the soil water tension. A weather station was installed besides the lysimeters, in order to supply weather information. Precipitation, volume of leachate, and trifluralin concentration in the effluent were measured during 65 days. There was no change on the SDI system flow rate. The LVA presented the highest amounts of leached compound, which was above the EPA limit and lower than the allowed by Brazilian law.

Dinitroaniline Herbicide Resistance and Mechanisms in Weeds

“…Originally it was used in soybean fields by pre-plant soil-incorporation for grass weed control ( Epp et al, 2017 ). Later on, trifluralin was introduced into Latin America and Asia Pacific and extensively used in sugarcane and soybean in Brazil ( Lima et al, 2018 ), and Australian cereal and legume fields ( Jolley and Johnstone, 1994 ). With the introduction of newly developed, highly efficient post-emergence ALS- and ACCase-inhibitors in 1980s, trifluralin usage declined and the trifluralin market was significantly replaced by these newer herbicides.…”

A identidade denegada. Discutindo as representações e a autorrepresentação dos caboclos da Amazônia

“…• Os que enfatizam práticas de manejo e formas de posse da terra, identificando os caboclos como produtores rurais, dentre os quais Brondízio & Siqueira (1997), Fraxe (2004) e Adams et al (2005); • Os que utilizam a ecologia política e a análise institucional na sua análise, como Lima (1992), Siqueira (1997), Murrieta et al (1999), Castro (1999, Futema (2000) e Winkles Prins (2001,2002); • Os que observam os caboclos na sua identidade sócio-econômica e política, como Lima (1992Lima ( , 1999, Furtado (1993), Alencar (1994), Simonian (1995), Lima et al (2000), Lima & Pozzobon (2001) e Furtado et Quaresma (2002); • Os que verticalizaram os modelos ecológicos funcionalistas, usando a ecologia comportamental, como Begossi (2004); • Os que focalizam processos ligados a práticas cotidianas e a motivações culturais subjacentes, como Murrieta (2000, 2001a, 2001b) e Harris (2000); • Os que enfatizam padrões biológicos nos processos de mudança experimentados pelas populações, como Silva & Eckhardt (1994), Silva (1995), Silva et al (1995), Siqueira (1997) e Adams (2002). Uma variação da pesquisa etnográfica sobre os caboclos é empreendida nos trabalhos que descrevem a inserção da figura do caboclo no discurso religioso amazônico.…”

“…Nas duas últimas colocações têm-se, na verdade, o mesmo teorema elaborado por Wagley (1957), por meio do qual se compreende o termo caboclo como uma categoria social relacional -ou seja, que o termo se refere não a uma condição étnica, mas sim a uma formação discursiva. Lima (1992Lima ( e 1999 explica essa condição: Na região amazônica, o termo caboclo é também empregado como categoria relacional. Nessa utilização, o termo identifica uma categoria de pessoas que se encontra numa posição social inferior em relação àquela com que o locutor ou a locutora se identifica.…”

The herbicides trifluralin and tebuthiuron have no genotoxic or mutagenic potential as evidenced by genetic tests

“…The herbicides trifluralin and tebuthiuron have been extensively used in Brazil and in other countries, mainly in sugarcane and soybean crops, to control weeds (Lima et al 2012). According to data from the Brazilian Institute of Environment and Renewable Natural Resources (IBAMA 2017), sales of trifluralin comprised 1467.41 tons in 2012 and 1594.00 tons in 2014.…”