Wheat yield and physical properties of a brown latosol under no-tillage in south-central Paraná

Soil management influences the chemical and physical properties of soil. Chemical conditions have been thoroughly studied, while the role of soil physical conditions regarding crop yield has been neglected. This study aimed to analyze the wheat yield and its relationship with physical properties of an Oxisol under no-tillage (NT). The study was carried out between 2010 and 2011, in Reserva do Iguaçu, State of Paraná, Brazil, on the Campo Bonito farm, after 25 years of NT management. Based on harvest maps of barley (2006), wheat (2007) and maize (2009) of a plot (150 ha), zones with higher and lower yield potential (Z1 and Z2, respectively) were identified. Sampling grids with 16 units (50 x 50 m) and three sampling points per unit were established. The wheat grain yield (GY) and water infiltration capacity (WIC) were evaluated in 2010. Soil samples with disturbed and undisturbed structure were collected from the 0.00-0.10 and 0.10-0.20 m layers. The former were used to determine soil organic carbon (Corg) levels and the latter to determine soil bulk density (BD), total porosity (TP), macroporosity (Mac), and microporosity (Mic). Soil penetration resistance (PR) and water content (SWC) were also evaluated. The wheat GY of the whole plot was close to the regional average and the yield between the zones differed significantly, i.e. 22 % higher in Z1 than in Z2. No significant variation in Mic was observed between zones, but Z1 had higher Corg levels, SWC, TP and Mac and lower BD than Z2 in both soil layers, as well as a lower PR than Z2 in the 0.00-0.10 m layer. Therefore, soil physical conditions were more restrictive in Z2, in agreement with wheat yield and zone yield potential defined a priori, based on the harvest maps. Soil WIC in Z1 was significantly higher (30 %) than in Z2, in agreement with the results of TP and Mac which were also higher in Z1 in both soil layers. The correlation analysis of data of the two layers showed a positive relationship between wheat GY and the soil properties TP, SWC and WIC.

Erosão hídrica pós-plantio em florestas de eucalipto na bacia do rio Paraná, no leste do Mato Grosso do Sul

Nas regiões tropicais, o desgaste provocado no solo por ação das águas da chuva, ou seja, a erosão hídrica é a mais importante forma de degradação do solo. Visto que os plantios florestais de eucalipto estão inseridos em ecossistemas sensíveis às perturbações antrópicas em razão de ocorrência de plantações em solos com baixos teores de argila, com baixa fertilidade natural e grande parte das plantações estabelecidas em antigas áreas agrícolas e de pastagens degradadas, surge a necessidade do entendimento dos processos que regem a erosão hídrica e suas relações com as perdas de solo e água nos sistemas florestais. Objetivaram-se com este trabalho calcular os valores de erosividade da chuva (fator R - EI30), estimar a tolerância de perda de solo (T) para as classes representativas nas áreas de estudo, avaliar as perdas de solo e água por erosão hídrica e verificar a influência, por meio de análise de componentes principais (ACP), de atributos físicos e matéria orgânica do solo sobre a erosão hídrica em florestas de eucalipto no estádio de pós-plantio. Os tratamentos constituíram de diferentes sistemas de manejo dos resíduos e da disposição de plantio (nível e desnível), em dois biomas distintos, Cerrado e Floresta, e solo descoberto. Os solos foram classificados como Latossolo Vermelho distrófico típico textura média-alta fase floresta (LVd1) e Latossolo Vermelho distrófico típico textura média-baixa fase cerrado (LVd2). O estudo foi realizado em áreas experimentais de plantio de eucalipto localizadas no município de Três Lagoas, na bacia do Rio Paraná, no leste do Mato Grosso do Sul. O índice de erosividade anual obtido foi de 6.792,7 MJ mm ha-1 h-1 ano-1. Os valores de T variaram de 9,0 a 11,0 Mg ha-1 ano-1, para o LVd2 e LVd1, respectivamente. As perdas de solo apresentaram valores em torno de 0 a 0,505 Mg ha-1 no LVd1 e de 0 a 0,853 Mg ha-1, no LVd2. A ACP evidenciou-se eficiente na discriminação dos sistemas de manejo em razão da interação entre os atributos físicos e matéria orgânica do solo e suas relações com a erosão hídrica, possibilitando visualizar de forma clara a influência do manejo sobre esses atributos e a relação de ambos com as perdas de solo e água.

ESTIMATIVA DA EROSIVIDADE DE CHUVAS NO ESTADO DO PARANÁ PELO MÉTODO DA PLUVIOMETRIA: ATUALIZAÇÃO COM DADOS DE 1986 A 2008

Três estimativas de erosividade de chuvas no Estado do Paraná foram feitas nas décadas de 1980-90, mas nenhuma outra depois. Os objetivos deste trabalho foram atualizar, numa quarta estimativa, as informações de erosividade anual das chuvas para o Paraná, com dados pluviométricos de 1986 a 2008; e gerar informações de erosividade mensal para identificar a distribuição temporal da erosividade. Foram utilizados os métodos pluviográfico e pluviométrico de determinação de erosividade. O primeiro serviu para revalidar equações prévias de correlação entre erosividade por pluviografia e por pluviometria, isso feito em três localidades; já o segundo, para calcular o coeficiente de chuva em 114 localidades, utilizando-se dados de precipitação média mensal e anual, e então a erosividade, com as equações de correlação revalidadas. Mapas de erosividade anual e mensal foram gerados por interpolações geoestatísticas. A erosividade variou entre 5.449 e 12.581 MJ mm ha-1 h-1 ano-1 e aumentou no sentido oeste, a partir da região metropolitana de Curitiba; e no sentido sul, a partir do noroeste paranaense. Isso resultou em maiores erosividades nas regiões centro-sul (Guarapuava), centro-ocidental (Campo Mourão), oeste (Cascavel) e, principalmente, sudoeste (Pato Branco). Também houve incremento de erosividade a partir da região metropolitana de Curitiba, no sentido leste, indicando o litoral como outra região crítica em termos de erosividade. A maior erosividade mensal ocorreu em janeiro (média estadual de 1394 MJ mm ha-1 h-1 mês-1), seguida por tendência de diminuição até agosto (331 MJ mm ha-1 h-1 mês-1), quando então tornou a aumentar. Porém, ocorrem dois importantes repiques de erosividade: um em maio e outro em outubro (843 e 1.173 MJ mm ha-1 h-1 mês-1, respectivamente), principalmente nas regiões sudoeste e oeste. Esses repiques coincidem com períodos de implantação de culturas de inverno ou de verão nessas regiões. Em relação à última estimativa de erosividade anual, feita em 1993, houve aumento da área delimitada pela linha isoerodente de 11.000 MJ mm ha-1 h-1 ano-1 nas regiões sudoeste e oeste e um deslocamento das linhas isoerodentes de 7.000 e 8.000 MJ mm ha-1 h-1 ano-1 para o sentido leste nas regiões norte pioneiro, centro-oriental e sudeste, sugerindo elevação da erosividade nessas regiões. Tais alterações de erosividade podem estar associadas às eventuais mudanças no clima da região, mas também ao simples fato de este estudo estar considerando maior quantidade de dados em relação aos estudos anteriores. Concluiu-se que as equações de correlação determinadas entre os métodos pluviográfico e pluviométrico, obtidas para o Paraná em trabalhos anteriores, continuam válidas; os meses críticos quanto à erosividade são janeiro, maio e outubro; e as menores erosividades ocorrem nas regiões noroeste e metropolitana do Estado.

Adubação Fosfatada para Alta Produtividade de Soja, Milho e Cereais de Inverno Cultivados em Rotação em Latossolos em Plantio Direto no Centro-Sul do Paraná

O Estado do Paraná não dispõe de um sistema de recomendação de adubação para rotação de culturas em plantio direto (PD). Em razão disso, utiliza indicações geradas para culturas individuais há mais de 30 anos e em preparo convencional. Este estudo teve como objetivo consolidar a calibração de P e avaliar a resposta das culturas à adubação fosfatada, visando à proposição de um sistema de indicações técnicas para a adubação fosfatada das culturas da soja, do milho, do trigo e da cevada cultivadas em sistema de rotação em Latossolos com longo histórico de PD (>30 anos) na região centro-sul do Paraná, que se caracteriza por possuir alto potencial produtivo. Três experimentos de calibração foram conduzidos de 2008 a 2013 e consistiram na criação de níveis de P pela aplicação de doses a lanço de até 640 kg ha-1 de P2O5. Quarenta e quatro experimentos de resposta a P foram conduzidos entre as safras de 2011 a 2012/13, tendo como foco avaliar a resposta das culturas a P em solos com distinta disponibilidade do nutriente. Os rendimentos relativos [RR = (rendimento sem P/rendimento máximo) × 100] das culturas e os teores de P no solo (Mehlich-1) foram relacionados, obtendo-se os teores críticos e as classes de disponibilidade de P no solo. Para a estimativa das doses nas classes de disponibilidade Baixa e Média, foram utilizadas as curvas de resposta à adubação de P, seguindo a filosofia de suficiência (adubação de cultura). Nas classes de disponibilidade Alta e Muito Alta, as doses foram com base na exportação pelos grãos. Os cereais de inverno se evidenciaram mais exigentes e determinaram o teor crítico de P de 8 mg dm-3 para a rotação de culturas, considerando a camada de 0-20 cm. As doses de P indicadas para soja, milho, trigo e cevada em solos em PD de longa duração são superiores às de adubação atualmente indicadas no PR, o que, ao menos em parte, justificam-se pelas altas produtividades das culturas e alta capacidade de retenção de P dos solos da região. Embora adotada a filosofia de suficiência/adubação de cultura para a indicação das doses de adubação fosfatada em solos abaixo do teor crítico, estima-se que as doses estipuladas para as culturas elevem o teor de P no solo ao teor crítico após um ciclo da rotação de culturas (três anos).

Genesis, Characterization, and Classification of Mangrove Soils in the Subaé River Basin, Bahia, Brazil

ABSTRACT Preservation of mangroves, a very significant ecosystem from a social, economic, and environmental viewpoint, requires knowledge on soil composition, genesis, morphology, and classification. These aspects are of paramount importance to understand the dynamics of sustainability and preservation of this natural resource. In this study mangrove soils in the Subaé river basin were described and classified and inorganic waste concentrations evaluated. Seven pedons of mangrove soil were chosen, five under fluvial influence and two under marine influence and analyzed for morphology. Samples of horizons and layers were collected for physical and chemical analyses, including heavy metals (Pb, Cd, Mn, Zn, and Fe). The moist soils were suboxidic, with Eh values below 350 mV. The pH level of the pedons under fluvial influence ranged from moderately acid to alkaline, while the pH in pedons under marine influence was around 7.0 throughout the profile. The concentration of cations in the sorting complex for all pedons, independent of fluvial or marine influence, indicated the following order: Na+>Mg2+>Ca2+>K+. Mangrove soils from the Subaé river basin under fluvial and marine influence had different morphological, physical, and chemical characteristics. The highest Pb and Cd concentrations were found in the pedons under fluvial influence, perhaps due to their closeness to the mining company Plumbum, while the concentrations in pedon P7 were lowest, due to greater distance from the factory. For containing at least one metal above the reference levels established by the National Oceanic and Atmospheric Administration (United States Environmental Protection Agency), the pedons were classified as potentially toxic. The soils were classified as Gleissolos Tiomórficos Órticos (sálicos) sódico neofluvissólico in according to the Brazilian Soil Classification System, indicating potential toxicity and very poor drainage, except for pedon P7, which was classified in the same subgroup as the others, but different in that the metal concentrations met acceptable standards.

Cedar-Iowa River Rail Transit Project Feasibility Study, November 9, 2006

Five Seasons Transportation & Parking (FSTP) and the Johnson County Council of Governments (JCCOG) are interested in evaluating the feasibility of prospective passenger rail service(s) that would operate over existing trackage of the Cedar Rapids and Iowa City Railway Company (CRANDIC), seen below left, and/or the Iowa Interstate Railroad System (IAIS), seen below right, connecting Cedar Rapids, Iowa City and the Amana Colonies. To perform the study, FSTP and JCCOG selected R.L. Banks & Associates, Inc. (RLBA) as Prime Contractors, HNTB Corporation (HNTB) and Snyder & Associates, Inc. (Snyder) as Subcontractors, hereafter Consultant Team. Both railroads participated in the study and contributed time and resources, as did many local government and civic organizations. The purpose of the study is to determine whether it is feasible to establish regularly scheduled passenger rail service and/or special event excursion rail service, in conjunction with the Five Seasons Transit system, Iowa City Transit, East Central Iowa Transit, Coralville Transit and the University of Iowa CAMBUS.

Missouri River Flood Recovery, January 27, 2012 Vol. 1, no. 5

The Missouri River Flood Recovery newsletter is published by the Iowa Homeland Security and Emergency Management Division in cooperation with members of the Missouri River Recovery Coordination Task Force.

Missouri River Flood Recovery, December 2, 2012 Vol. 1, no. 3

The Missouri River Flood Recovery newsletter is published by the Iowa Homeland Security and Emergency Management Division in cooperation with members of the Missouri River Recovery Coordination Task Force.

Missouri River Flood Recovery, November 4, 2012 Vol. 1, no. 1

The Missouri River Flood Recovery newsletter is published by the Iowa Homeland Security and Emergency Management Division in cooperation with members of the Missouri River Recovery Coordination Task Force.

Missouri River Flood Recovery, November 18, 2012 Vol. 1, no. 2

The Missouri River Flood Recovery newsletter is published by the Iowa Homeland Security and Emergency Management Division in cooperation with members of the Missouri River Recovery Coordination Task Force.

Missouri River Flood Recovery, December 23, 2012 Vol. 1, no. 4

The Missouri River Flood Recovery newsletter is published by the Iowa Homeland Security and Emergency Management Division in cooperation with members of the Missouri River Recovery Coordination Task Force.

Missouri River Flood Coordination Task Force Report, September 25, 2011

The Missouri River floods of 2011 will go down in history as the longest duration flooding event this state has seen to date. The combination of above normal snowfall in the upper Missouri River basin followed by the equivalent of nearly one year’s worth of rainfall in May created an above normal runoff situation which filled the Missouri River and the six main reservoirs within the basin. Compounding this problem was colder than normal temperatures which kept much of the snowpack in the upper basin on the ground longer into the spring, setting the stage for this historic event. The U.S. Army Corps of Engineers (USACE) began increasing the outflow at Gavin’s Point, near Yankton, South Dakota in May. On June 14, 2011, the outflow reached a record rate of over 160,000 cubic feet per second (cfs), over twice the previous record outflow set in 1997. This increased output from Gavin’s Point caused the Missouri River to flow out of its banks covering over 283,000 acres of land in Iowa, forcing hundreds of evacuations, damaging 255,000 acres of cropland and significantly impacting the levee system on the Missouri River basin. Over the course of the summer, approximately 64 miles of primary roads closed due to Missouri River flooding, including 54 miles of Interstate Highway. Many county secondary roads were closed by high water or overburdened due to the numerous detours and road closures in this area. As the Missouri River levels began to increase, municipalities and counties aided by State and Federal agencies began preparing for a sustained flood event. Citizens, businesses, state agencies, local governments and non‐profits made substantial preparations, in some cases expending millions of dollars on emergency protective measures to protect their facilities from the impending flood. Levee monitors detected weak spots in the levee system in all affected counties, with several levees being identified as at risk levees that could potentially fail. Of particular concern was the 28 miles of levees protecting Council Bluffs. Based on this concern, Council Bluffs prepared an evacuation plan for the approximately 30,000 residents that resided in the protected area. On May 25, 2011, Governor Branstad directed the execution of the Iowa Emergency Response Plan in accordance with Section 401 of the Stafford Act. On May 31, 2011, HSEMD Administrator, Brigadier General J. Derek Hill, formally requested the USACE to provide technical assistance and advanced measures for the communities along the Missouri River basin. On June 2, 2011 Governor Branstad issued a State of Iowa Proclamation of Disaster Emergency for Fremont, Harrison, Mills, Monona, Pottawattamie, and Woodbury counties. The length of this flood event created a unique set of challenges for Federal, State and local entities. In many cases, these organizations were conducting response and recovery operations simultaneously. Due to the length of this entire event, the State Emergency Operations Center and the local Emergency Operations Centers remained open for an extended period of time, putting additional strain on many organizations and resources. In response to this disaster, Governor Branstad created the Missouri River Recovery Coordination Task Force to oversee the State’s recovery efforts. The Governor announced the creation of this Task Force on October 17, 2011 and appointed Brigadier General J. Derek Hill, HSEMD Administrator as the chairman. This Task Force would be a temporary group of State agency representatives and interested stakeholders brought together to support the recovery efforts of the Iowa communities impacted by the Missouri River Flood. Collectively, this group would analyze and share damage assessment data, coordinate assistance across various stakeholders, monitor progress, capture best practices and identify lessons learned.

Reservoir compensation releases : impact on the macroinvertebrate community of the Derwent River, Northumberland, UK-A longitudinal

River regulation for the purposes of public water supply causes the flow regime downstream of a dam to change. Traditionally, in the UK, such regulation was accompanied by requirements for reservoir releases to compensate downstream water users (e.g. industry) for the loss of natural flow (compensation flows). In this article, we compare a unique pre-impoundment macroinvertebrate data set for a regulated upland river with survey data post-impoundment. This allows a longitudinal assessment of the response of the system to regulation. The Derwent River, Northumberland, was impounded in 1966. Impacts on the hydrological regime were quantified by comparing long-term hydrographs, flow duration curves, flow ranges and flashiness indices for the pre-impoundment and post-impoundment periods. The comparison of changes in macroinvertebrate richness and diversity post-impoundment showed that the change in flow regime has had limited effect on the ecological community structure. The flow regime of the Derwent River has become less flashy with fewer extreme events, and the richness and the diversity of macroinvertebrates have, in some cases, increased and at worst have not deteriorated. We suggest that this reflects the strict compensation regime, which has guaranteed minimum flows at all times. Copyright (c) 2012 John Wiley & Sons, Ltd.