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Food allergy triggers an immune response to dietary proteins, resulting in food rejection and dermatological and gastrointestinal manifestations. The preferred therapies include diets with hydrolyzed proteins or unusual single-source proteins, with insect protein emerging as a promising option, with no reported allergic reactions in dogs with a food allergy. In this case study, the effects of including black soldier fly larva (BSFL) meal were observed in a 5-year-old spayed beagle previously diagnosed with a food allergy. The objective was to assess the potential of BSFL meal as an adjunct in treating a food allergy. As part of the protocol, two nutritionally very similar diets were used, differing only in the protein source: the control diet, with poultry by-product meal; and the BSFL diet, which completely replaced the poultry by-product meal. After a 12-day adaptation period to the BSFL diet, the dog showed no gastrointestinal changes, maintaining an adequate fecal score and no clinical signs of the disease. A challenge test with the control diet resulted in episodic gastrointestinal symptoms, which were reversed within two days by reintroducing the BSFL diet. The BSFL protein-based diet was effective in controlling the dog’s clinical signs.

Introduction: Stroke is one of the leading causes of death in Latin America, a region with countless gaps to be addressed to decrease its burden. In 2018, at the first Latin American Stroke Ministerial Meeting, stroke physician and healthcare manager representatives from 13 countries signed the Declaration of Gramado with the priorities to improve the region, with the commitment to implement all evidence-based strategies for stroke care. The second meeting in March 2020 reviewed the achievements in 2 years and discussed new objectives. This paper will review the 2-year advances and future plans of the Latin American alliance for stroke.Method: In March 2020, a survey based on the Declaration of Gramado items was sent to the neurologists participants of the Stroke Ministerial Meetings. The results were confirmed with representatives of the Ministries of Health and leaders from the countries at the second Latin American Stroke Ministerial Meeting.Results: In 2 years, public stroke awareness initiatives increased from 25 to 75% of countries. All countries have started programs to encourage physical activity, and there has been an increase in the number of countries that implement, at least partially, strategies to identify and treat hypertension, diabetes, and lifestyle risk factors. Programs to identify and treat dyslipidemia and atrial fibrillation still remained poor. The number of stroke centers increased from 322 to 448, all of them providing intravenous thrombolysis, with an increase in countries with stroke units. All countries have mechanical thrombectomy, but mostly restricted to a few private hospitals. Pre-hospital organization remains limited. The utilization of telemedicine has increased but is restricted to a few hospitals and is not widely available throughout the country. Patients have late, if any, access to rehabilitation after hospital discharge.Conclusion: The initiative to collaborate, exchange experiences, and unite societies and governments to improve stroke care in Latin America has yielded good results. Important advances have been made in the region in terms of increasing the number of acute stroke care services, implementing reperfusion treatments and creating programs for the detection and treatment of risk factors. We hope that this approach can reduce inequalities in stroke care in Latin America and serves as a model for other under-resourced environments.

Background: Stroke is the second leading cause of death and disability worldwide. Stroke centers have become a central component of modern stroke services in many high-income countries, but their feasibility and efficacy in low, middle, and emerging high-income countries are less clear. Also, despite the availability of international guidelines, many hospitals worldwide do not have organized clinical stroke care. We present a methodology to help hospitals develop stroke centers and review quality data after implementation.Objectives: To describe and compare demographics, performance, and clinical outcomes of the Pacífica Salud, Hospital Punta Pacífica (PSHPP) stroke center during its first 3 years 2017–2019.Methods: Pacífica Salud, Hospital Punta Pacífica was organized to implement protocols of care based on the best practices by international guidelines and a quality improvement process. The methodology for implementation adapts a model for translating evidence into practice for implementation of evidence-based practices in medicine. This is a retrospective study of prospectively collected quality data between March of 2017 to December of 2019 for patients admitted to PSHPP with primary diagnosis stroke. Data collected include demographics, clinical data organized per the Joint Commission's STK Performance Measures, door to needle, door to groin puncture, 90 day modified Rankin Score, and hemorrhagic complications from IV thrombolysis and mechanical thrombectomy (MT). Primary outcome: year over year proficiency in documenting performance measures. Secondary outcome: year over year improvement.Results: A total of 143 patients were admitted for acute ischemic stroke, TIA, or hemorrhagic stroke. Of these, 36 were admitted in 2017, 50 in 2018, and 57 in 2019. Performance measure proficiency increased in the year-over-year analysis as did the total number of patients and the number of patients treated with IV thrombolysis and MT.Conclusions: We present the methodology and results of a stroke program implementation in Panamá. This program is the first in the country and in Central America to achieve Joint Commission International (JCI) certification as a Primary Stroke Center (PSC). We postulate that the dissemination of management guidelines is not sufficient to encourage the development of stroke centers. The application of a methodology for translation of evidence into practice with mentorship facilitated the success of this program.

Abstract Individuals with autism spectrum disorder (ASD) suffer from developmental disabilities that impact communication, behavior, and social interaction. Immune dysregulation and inflammation have been linked to children with ASD, the latter manifesting in serum levels of macrophage‐derived chemokine (MDC) and thymus, and activation‐regulated chemokine (TARC). Mesenchymal stem cells derived from umbilical cord tissue (UC‐MSCs) have immune‐modulatory and anti‐inflammatory properties, and have been safely used to treat a variety of conditions. This study investigated the safety and efficacy of UC‐MSCs administered to children diagnosed with ASD. Efficacy was evaluated with the Autism Treatment Evaluation Checklist (ATEC) and the Childhood Autism Rating Scale (CARS), and with measurements of MDC and TARC serum levels. Twenty subjects received a dose of 36 million intravenous UC‐MSCs every 12 weeks (four times over a 9‐month period), and were followed up at 3 and 12 months after treatment completion. Adverse events related to treatment were mild or moderate and short in duration. The CARS and ATEC scores of eight subjects decreased over the course of treatment, placing them in a lower ASD symptom category when compared with baseline. MDC and TARC inflammatory cytokine levels also decreased for five of these eight subjects. The mean MDC, TARC, ATEC, and CARS values attained their lowest levels 3 months after the last administration. UC‐MSC administration in children with ASD was therefore determined to be safe. Although some signals of efficacy were observed in a small group of children, possible links between inflammation levels and ASD symptoms should be further investigated. Stem Cells Translational Medicine 2019;8:1008–1016

Abstract The use of biosimilar drugs for multiple sclerosis (MS) has become widespread in Latin America, with the goal of reducing costs of treatments, promoting the sustainability of healthcare systems, and improving patient access to these therapies. There is currently a need to define and comply with requirements to guarantee the efficacy, safety, and quality of these drugs. Thus, the objective of the present study was to compile up-to-date information from each Latin American country assessed on (a) approval of biosimilar drugs by regulatory agencies; (b) use of biosimilar drugs, pharmacovigilance plans, risk management; and (c) update in the knowledge on different molecules. To do so, a group of experts from Argentina, Bolivia, Brazil, Chile, Colombia, Costa Rica, Ecuador, Mexico, Panama, Peru, Uruguay, and Venezuela met to discuss the current situation regarding good practices and risks associated with the use of biosimilar drugs in their respective countries. Regulation, risk management plans, and pharmacovigilance in the whole continent must guide the strategies on the commercialization and access of biosimilar drugs and copies of complex molecules. Current regulations must be implemented for the registration of biosimilar drug products and complex molecules. It is paramount to ensure that new products follow the best quality standards at all stages beyond being safe and efficient. Uncontrolled interchangeability between original biological and biosimilar should be avoided. Latin America requires the implementation and full use of strong pharmacovigilance programs. National and multinational clinical studies are required to demonstrate the similarity in safety, efficacy, and immunogenicity profiles of complex molecules, as well as biological and biosimilar products. Plain Language Summary Plain language summary available for this article.

The dengue fever is a major public health problem in the world. In Brazil, in 2015, there were 1,534,932 cases, being 20,320 cases of severe form, and 811 deaths related to this disease. The distribution of Aedes aegypti, the vector, is extensive. Recently, Zika and Chikungunya viruses had arisen, sharing the same vector as dengue and became a huge public health issue. Without specific treatment, it is urgently required as an effective vector control. This article is focused on reviewing vector control strategies, their effectiveness, viability and economical impact. Among all, the Sterile Insect Technique is highlighted as the best option to be adopted in Brazil, once it is largely effectively used in the USA and Mexico for plagues related to agribusiness. Keywords: Dengue, Vector control, Aedes, Arbovirus, Sterile insect technique

Basándose en el marco de los indicadores de derechos humanos para la política pública, el presente artículo brinda un análisis de la perspectiva fiscalista empleada por el gobierno de Ecuador después del terremoto del 16 de abril de 2016, para administrar y gestionar el desastre natural y la reconstrucción. Dicha perspectiva conllevó a la vulneración de algunos derechos humanos, afectó las capacidades de resiliencia de la población, y dificultó la generación de condiciones adecuadas para mejorar la situación de las poblaciones afectadas en Muisne, Chamanga y Canoa. De esta manera, empleando herramientas etnográficas y georreferenciales, este artículo permite entender la lógica de la aguda verticalidad de la gestión de reconstrucción y los efectos que tiene sobre la población, así como los procesos de reconstitución del tejido socioeconómico.

Se evaluó el comportamiento de metabolitos sanguíneos energéticos y proteicos con el uso de mezclas de Moringa oleífera : Pennisetum purpureum clon OM-22. Se utilizaron cuatro machos caprinos de raza Alpina, con 37.78 ±4.87 kg de peso vivo, dos años de edad y alojados en jaulas metabólicas individuales, or - ganizados en un diseño cuadrado latino (4x4). El tiempo experimental fue 60 días, con cuatro periodos de 15 días. Los tratamientos consistie - ron en la inclusión creciente de Moringa oleífera (MO20%, MO40%, MO80%) en sustitución de Pennisetum purpureum clon OM-22 (20:80, 40:60; 80:20%) en la mezcla integral y un testigo, al que se le ofertó concentrado comer - cial (6g kg PV -1 ). La totalidad de los forrajes frescos fueron cosechados, molidos (3-5cm) y mezclados, ofertados a razón del 3% del peso vivo base seca, en dos ocasiones (10:30-16:30 horas) durante el día. El estado de los metaboli - tos sanguíneo fue evaluado 22 horas posteriores al consumo de alimento. Las concentraciones de Glucosa, Colesterol, Triglicéridos y Urea se mantuvieron dentro del rango fisiológico. Los valores de Urea y Colesterol mostraron una ten - dencia creciente con la moringa en la mezcla, a diferencia de los Triglicéridos, que disminu - yeron. Los niveles de Creatinina en MO40 y MO80% superaron el límite fisiológico para la especie (59.7-134.8 μmol/l), indicando un posible fallo renal. Estos resultados permiten concluir que la Moringa oleífera con un nivel de inclusión del 20% constituye una alternativa alimentaria para caprinos; pero requiere de es - tudios para dilucidar niveles de Creatinina con la inclusión de 40 y 80% moringa.

Slash-and-burn agriculture has been practiced for thousands of years in the forests around the world, especially in the tropics, where it provides for the livelihood of countless poor rural populations. Characterized by an array of techniques based on crop diversification and shifting land use, this cultivation system has on the utilization of forest decomposing vegetation´s energetic capital its main asset. Many studies claim that slash-and-burn agriculture is sustainable only when performed under conditions of low human demographic density and maintenance or even increase of local biodiversity. However, it is growing in the academic literature, as well as in development debates, the concern regarding the role that this system has been playing in the deforestation of the planet´s tropical forests. This process appears to be closely linked to changes in land use patterns (agricultural intensification) and urban and rural demographic growth. On the thread of these concerns, this article presents a critical review of the international and national academic literature on slash-and-burn agriculture. Thus, this review intend to draw a broad scenario of the current academic debate on this issue, as well as to identify the main alternatives strategies proposed to maintain or replace this cultivation system.

This study aims to characterize the socioeconomic and demographic profile of nine Quilombola populations in the Ribeira Valley, State of São Paulo, and to identify the main factors responsible for the recent changes in their subsistence system. Since the first assemblages of runway and abandoned slaves in the 18th. century, the relations established by these populations with nearby towns and regional market have gone through periods of expansion and retraction, adapting and adjusting to new socioeconomic and political changes. In the last five decades, the impact of external factors on the local subsistence patterns appears to have had a significant increase. Our results show that restrictions imposed by environmental laws, conflict over land, the construction of a major road in the region, the growing insertion into a market economy, and the intervention of governmental and non-governmental development agencies are the main factors behind the changes observed in the subsistence system and, consequently, in the socioeconomic organization of these populations.

O objetivo deste trabalho foi avaliar a eficiência bioeconômica de cordeiros F1 Dorper x Santa Inês para produção de carne. Analisou-se o desempenho de ovinos ½ sangue Dorper x ½ sangue Santa Inês, nas fases de cria e de acabamento. A fase de produção das crias foi realizada em caatinga nativa e a fase de acabamento em confinamento. As matrizes foram suplementadas nos últimos 50 dias de prenhez e nos primeiros 30 dias de lactação. As crias foram desmamadas aos 70 dias de idade, divididas em três lotes e confinadas, alimentadas com capim-elefante (Pennisetum purpureum) ad libitum e concentrado na proporção de 1,5%, 2,5% e 3,5% do peso vivo, respectivamente. O sexo não exerceu influência sobre os pesos no nascimento, no desmame, nem sobre o ganho em peso até o desmame. Não foi observada influência do sexo sobre os pesos e os ganhos em peso aos 30 e 50 dias de confinamento. Nas fases de produção e acabamento em confinamento, os animais de nascimento simples foram superiores aos de nascimento duplo quanto a essas variáveis. Houve efeito linear significativo para peso e ganho em peso aos 30 e 50 dias de confinamento. Os três níveis de uso de concentrado foram economicamente viáveis. As margens brutas de peso vivo, por kg de cordeiro produzido, foram de R$ 0,26 kg-1, R$ 0,30 kg-1 e R$ 0,36 kg-1 para concentrados a 1,5%, 2,5% e 3,5% do peso vivo, respectivamente. Os melhores resultados econômicos foram obtidos quando o nível de concentrado foi de 3,5% do peso vivo.The objective of this work was to evaluate bioeconomic efficiency of F1 Dorper x Santa Inês lambs for meet production. Performance of F1 Dorper x Santa Inês lambs in raising and fattening phases was analyzed. The production phase of lambs was realized in native pastures ("caatinga") and the finishing phase was in confinement. The ewes were supplemented during the last 50 days of pregnancy and the first 30 days of lactation. Lambs were weaned at 70 days of age, divided into three lots, confined and fed elephant grass (Pennisetum purpureum) ad libitum, and concentrate in the proportion of 1.5%, 2.5% and 3.5% of live weight, respectively. Lambs sex did not have significant influence on birth weight, as well as on weaning weight and weight gain until weaning. In production and confinement phases, lambs of single births were superior to double births ones considering these variables. Linear effect was significant for weight and for weight gain, at 30 and 50 days of confinement. The three inclusion levels of concentrate were economically viable. Gross margins of live weight for each kg of lamb produced were R$ 0.26 kg-1, R$ 0.30 kg-1 and R$ 0.36 kg-1 of live weight to concentrates of 1.5%, 2.5% and 3.5%, respectively. The best economics results were obtained when the concentrate level was 3.5% of live weight.

O potencial de produção de trinta e cinco cabras mestiças - 12 ½Pardo-alpina + ½Moxotó (½PA-M), 11¾ Pardo-alpina + ¼Moxotó (¾PA-M) e 12 Tricross (½Anglo-nubiana + ¼Pardo-alpina + ¼Moxotó) - foi avaliado em um experimento foi conduzido na Embrapa Caprinos. Os cabritos foram separados das respectivas mães ao nascimento. As cabras foram ordenhadas duas vezes ao dia e o controle leiteiro procedido semanalmente. Os animais foram confinados em baias coletivas e receberam dieta para produção de 2,5 kg de leite/dia, composta de silagem de sorgo ad libitum e concentrado. Os animais foram pesados em intervalos de 14 dias. A produção de leite, como coletada, não foi influenciada pelo genótipo. No entanto, quando foi corrigida para 4% de gordura, o genótipo ½ PA-M foi superior aos ¾ PA-M e Tricross. Não houve diferença significativa entre genótipos para gordura, proteína e extrato seco total do leite.The objective of this trial was to study the production of thirty-five crossbred goats: ½Brown Alpine x 12 ½Moxoto (½BA-M), 11 ¾Brown Alpine x ¼Moxoto (¾BA-M), and 12 Tricross (½Anglo Nubian x ¼Moxoto x ¼Brown Alpine). After birth, the kids were separated from their mothers. Goats were milked twice a day and milk composition determined weekly. Animals were housed in collective pens and received a diet composed of sorghum silage (ad libitum) plus concentrate that were formulated to allow 2.5 kg/d of milk yield. Animals were weighted every 14 days. Milk production did not differ among genotypes. However, 4% fat corrected milk was greater for ½BA-M than the remaining groups. No significant differences were observed for milk composition (fat, protein, and total solids) across genotypes in the current trial.

O objetivo deste trabalho foi determinar a influência do reprodutor nas características de crescimento de 303 cordeiros para abate, dos grupos genéticos ½ sangue Somalis Brasileira x Sem Raça Definida (SRD) e ½ sangue Santa Inês x SRD. Os animais foram pesados a intervalos de 14 dias, até o desmame na época seca, e até 140 dias de idade na época chuvosa. O grupo genético e o ano de nascimento não influenciaram (P>0,05) nenhuma das características avaliadas. O mês de nascimento influenciou (PThe aim of this work was to determine the influence of the ram in the growth traits of 303 slaughter lambs of ½ Somalis Brasileira x ½ Undefined Breed (SRD) and ½ Santa Inês x ½ SRD genetic groups. The animals were weighted each 14 days until weaning at dry season and up to 140 days of age at rainy season. The genetic group and the year of birth did not influence (P>0.05) any of the analyzed traits. The month of birth influenced (P

Foram utilizados 32 cordeiros, mestiços, durante setenta dias em estudo na Embrapa Caprinos, em Sobral, CE, para determinar a influência do nível de concentrado em dietas para acabamento de cordeiros em confinamento. Os tratamentos foram as seguintes relações forragem:concentrado: 100%:0% (T1), 85%:15% (T2), 70%:30% (T3) e 55%:45% (T4). A forragem fornecida era feno de cunhã e o concentrado era composto de 75% de milho e 25% de farelo de soja. O ajuste das proporções foi feito diariamente, com base no consumo de volumoso, servido ad libitum. Com o aumento do nível de concentrado na dieta dos animais, observou-se incrementos lineares (P0,05) quanto aos tratamentos. Conclui-se que todas as rações testadas podem ser utilizadas para terminação de cordeiros, em confinamento.

Studies were carried out to characterize microhabitat occupation by birds in a restinga fragment of Paraná coast. Were described 14 microhabitats occupied in different manners for 64 species of birds. Based on the results, could be suggested that this conspicuous class of vertebrates, together with the other elements that integrate the restinga, serve as a component to attract and stimulate the interest for the comprehension and necessity of conservation by the visitors of such ecosystem.Os cordões de restinga formam um ecossistema cuja extensão já se encontra bastante reduzida, devido à sua localização em áreas de grande interesse urbano, industrial e turístico. Nesse estudo caracterizou-se uma parcela desse tipo de ambiente e foram descritos 14 diferentes microhabitats ocupados diferencialmente por 64 espécies de aves. Sugere-se que essa conspícua classe de vertebrados, junto com os demais elementos que integram o ambiente de restinga, sirva como um componente para atrair e estimular o interesse pela compreensão e necessidade de conservação por parte dos frequentadores desse tipo de ambiente.

O objetivo desta pesquisa foi avaliar a composição centesimal e lipídica da carne de ovinos do Nordeste brasileiro. Para isso, foram utilizados 21 borregos, machos inteiros, sendo 10 animais ½ Somalis Brasileira ´ ½ Crioula (SB-C) e 11 animais ½ Santa Inês ´ ½ Crioula (SI-C). Os animais receberam duas dietas durante a fase de amamentação: feno de capim-gramão (Cynodon dactylon) + feno de leucena (Leucaena leucocephala) ad libitum (D1) e feno de capim-gramão + feno de leucena + concentrado com 20% de proteína bruta ad libitum (D2). Não foi observado o efeito dos genótipos nem do sistema de alimentação sobre a composição centesimal e lipídica da carne. Os valores de umidade, proteína, cinzas e gordura, variaram de 76,12 a 76,19%, 19,19 a 19,46%, 1,08 a 1,10% e 2,01 a 2,39%, respectivamente. Os valores de colesterol variaram de 54,43 a 60,05mg por 100g de carne. Os ácidos graxos encontrados em maior quantidade na fração lipídica da carne dos animais estudados foram oleico, palmítico e esteárico. De acordo com os resultados obtidos, conclui-se que a carne de ovinos do Nordeste brasileiro apresenta uma composição centesimal e lipídica similar às carnes de ovinos de clima temperado.The objective of this study was to evaluate the proximate and lipidic compositon of lamb meat from tropical sheep reared in Northeastern Brazil. Twenty-one rams, ten ½ Somalis Brasileira ½ ´ Crioula (SB-C) and 11 ½ Santa Inês ´ ½ Crioula (SI-C) were used. Two feeding regimes were utilized during weaning: grass hay (Cynodon dactylon) + leucena hay (Leucaena leucocephala) ad libitum (D1) and grass háy + leucena hay + 20% crude protein concentrate ad libitum (D2). It was not observed effect of crossbreed or feeding regime on proximate and lipidic composition of the meat. Moisture, protein, ash and fat values varied from 76.12 to 76.19%, 19.19 to 19.46%, 1.08 to 1.10% and 2.01 to 2.39%, respectively. Cholesterol content ranged from 54.43 to 60.05mg/100g of meat. The more abundant fatty acids in lamb fat were oleic, palmitic and stearic. Based on these results, it can be concluded that lamb meat from Notheastern Brazil has proximal and lipidic compositions similar to that animals from temperate regions of the World.

Foi realizado um experimento para avaliar a influência da suplementação alimentar na produção de leite de cabras da raça Anglo-nubiana, durante a época chuvosa, na região semi-árida do Nordeste brasileiro. Vinte e quatro cabras foram mantidas em pastagem nativa rebaixada, distribuídas ao acaso, por tipo de parto e produção de leite, em três níveis de suplementação: N0 - sem suplementação, N1 -150 g de concentrado/animal/dia e N2 - 300 g de concentrado/animal/dia. Não houve diferença significativa (p>0,05) entre os níveis de suplementação. A produção de leite foi descrita por uma regressão múltipla em função do período de lactação em semana. A interação semana x níveis de suplementação foi significativa (pThis experiment was carried out to evaluate the influence of food supplementation on milk production of Anglo-nubian goats, during the rainy season, in semi-arid region of Northeast Brazil. Twenty four goats were maintained in lowered "caatinga", distributed randomly according to the parturition order and milk production in three supplementation levels: N0 - no supplementation, N1 - 150 g of concentrate/animal/day and N2 - 300 g of concentrate/animal/day. There was no significant difference (p>0.05) between supplementation levels. Milk production was described by multiple regression to lactation period, in week. The results showed that the best option to produce milk with Anglo-nubian, during the wet season, is 300 g of concentrate/animal/day.

This paper presents the main results of a research on recent immigration to Brazil whose objectives were surveying the sources of data, discussing the quality of information available and outlining the profiles of the immigrant population in the end of the last century. The data banks examined, although not necessarily built up to keep track of the influx of immigrants to Brazil, allowed us to trace the characteristics of the stock of foreigners resident in Brazil as well as those of the flow ofimmigrants recently arrived. We observed population movements related to the privatization process and sales of national companies to foreign capital, e.g., Spanish, as well as movements of economically excluded people, such as Bolivians, struggling to survive. Both movements clearly represent the two faces of the same coin, and together reflect the characteristics of modern capitalism.

O artigo estuda os produtores eventuais de café de Bananal (SP) - cafeicultores em pelo menos um dos anos entre 1799 e 1828 e que haviam abandonado a lide cafeeira em 1829, ou então não figuravam no resenceamento atinente a este último ano. Tomando como fontes as listas nominativas de habitantes e o Censo de Terras, visa-se ao aprofundamento do conhecimento acerca dos primevos da cafeicultura paulista. O exame de elementos demográficos e econômicos permitiu a caracterização dos produtores eventuais de café. Seus domicílios eram chefiados por pessoas em média mais velhas. Adiconalmente, tais fogos apresentavam-se menos favorecidos em termos da distribuição das propriedades escrava e fundiária. A grande maioria dos indivíduos em questão exercia sua faina agrícola em terras alheias. Eram, ademais, precárias as condições materiais em que se viviam, bem como elevada sua mobilidade espacial. Economia cafeeira, demografia história, lavradores pobres, propriedade fundiária, posse escrava, Bananal.

Abstract Background The World Health Organization (WHO) collects and publishes surveillance data and statistics for select diseases, but traditional methods of gathering such data are time and labor intensive. Event-based biosurveillance, which utilizes a variety of Internet sources, complements traditional surveillance. In this study we assess the reliability of Internet biosurveillance and evaluate disease-specific alert criteria against epidemiological data. Methods We reviewed and compared WHO epidemiological data and Argus biosurveillance system data for pandemic (H1N1) 2009 (April 2009 – January 2010) from 8 regions and 122 countries to: identify reliable alert criteria among 15 Argus-defined categories; determine the degree of data correlation for disease progression; and assess timeliness of Internet information. Results Argus generated a total of 1,580 unique alerts; 5 alert categories generated statistically significant (p Conclusion Confirmed pandemic (H1N1) 2009 cases collected by Argus and WHO methods returned consistent results and confirmed the reliability and timeliness of Internet information. Disease-specific alert criteria provide situational awareness and may serve as proxy indicators to event progression and escalation in lieu of traditional surveillance data; alerts may identify early-warning indicators to another pandemic, preparing the public health community for disease events.

Abstract Background Despite strong support for predictive validity of the theory of planned behavior (TPB) substantial variance in both intention and behavior is unaccounted for by the model’s predictors. The present study tested the extent to which habit strength augments the predictive validity of the TPB in relation to a currently under-researched behavior that has important health implications, namely children’s active school travel. Method Participants (N = 126 children aged 8–9 years; 59 % males) were sampled from five elementary schools in the west of Scotland and completed questionnaire measures of all TPB constructs in relation to walking to school and both walking and car/bus use habit. Over the subsequent week, commuting steps on school journeys were measured objectively using an accelerometer. Hierarchical multiple regressions were used to test the predictive utility of the TPB and habit strength in relation to both intention and subsequent behavior. Results The TPB accounted for 41 % and 10 % of the variance in intention and objectively measured behavior, respectively. Together, walking habit and car/bus habit significantly increased the proportion of explained variance in both intention and behavior by 6 %. Perceived behavioral control and both walking and car/bus habit independently predicted intention. Intention and car/bus habit independently predicted behavior. Conclusions The TPB significantly predicts children’s active school travel. However, habit strength augments the predictive validity of the model. The results indicate that school travel is controlled by both intentional and habitual processes. In practice, interventions could usefully decrease the habitual use of motorized transport for travel to school and increase children’s intention to walk (via increases in perceived behavioral control and walking habit, and decreases in car/bus habit). Further research is needed to identify effective strategies for changing these antecedents of children’s active school travel.

Abstract Background The school commute is a prime opportunity to increase children's physical activity levels. However, active commuting has decreased over the past 40 years. Strategies that increase walking to school are therefore needed. Travelling Green (TG) is a school-based active travel resource aimed at increasing children's walking to school. The resource consists of a curriculum-based program of lessons and goal setting activities. A previous study found that children who received the TG intervention increased self-reported distance travelled to school by active modes and reduced the distance travelled by inactive modes. This study was limited by self-reported outcome measures, a small sample, and no follow-up measures. A more robust evaluation of TG is required to address these limitations. This paper describes the rationale and methods for such an evaluation of Travelling Green, and describes the piloting of various active commuting measures in primary school children. Methods/Design Measures of active commuting were piloted in a sample of 26 children (aged 8-9 years) over one school week. These measures were subsequently used in an 18-month quasi-experimental design to evaluate the effect of TG on commuting behaviour. Participants were 166 children (60% male) aged 8-9 years from 5 primary schools. Two schools (n = 79 children) received TG in September/October 2009. Three schools (n = 87 children) acted as a comparison group, and subsequently received TG at a later date. Physical activity was measured using Actigraph GT1M accelerometers. Personal and environmental determinants of active commuting were measured via parent and child questionnaires, as were factors related to the Theory of Planned Behaviour and the construct of habit. Measures were taken pre- and post-intervention and at 5 and 12 months follow-up. Discussion The piloted protocol was practical and feasible and piloted measures were reliable and valid. All study data, including 5 and 12 month follow-up, have been collected and processed. Data analysis is ongoing. Results will indicate whether TG successfully increases active commuting in a sample of Scottish school children and will inform future efforts in school active travel promotion.

Abstract Background Walking and cycling to school provide a convenient opportunity to incorporate physical activity into an adolescent's daily routine. School proximity to residential homes has been identified as an important determinant of active commuting among children. The purpose of this study is to identify if distance is a barrier to active commuting among adolescents, and if there is a criterion distance above which adolescents choose not to walk or cycle. Methods Data was collected in 2003–05 from a cross-sectional cohort of 15–17 yr old adolescents in 61 post primary schools in Ireland. Participants self-reported distance, mode of transport to school and barriers to active commuting. Trained researchers took physical measurements of height and weight. The relation between mode of transport, gender and population density was examined. Distance was entered into a bivariate logistic regression model to predict mode choice, controlling for gender, population density socio-economic status and school clusters. Results Of the 4013 adolescents who participated (48.1% female, mean age 16.02 ± 0.661), one third walked or cycled to school. A higher proportion of males than females commuted actively (41.0 vs. 33.8%, χ2 (1) = 22.21, p < 0.001, r = -0.074). Adolescents living in more densely populated areas had greater odds of active commuting than those in the most sparsely populated areas (χ2 (df = 3) = 839.64, p < 0.001). In each density category, active commuters travelled shorter distances to school. After controlling for gender and population density, a 1-mile increase in distance decreased the odds of active commuting by 71% (χ2 (df = 1) = 2591.86, p < 0.001). The majority of walkers lived within 1.5 miles and cyclists within 2.5 miles. Over 90% of adolescents who perceived distance as a barrier to active commuting lived further than 2.5 miles from school. Conclusion Distance is an important perceived barrier to active commuting and a predictor of mode choice among adolescents. Distances within 2.5 miles are achievable for adolescent walkers and cyclists. Alternative strategies for increasing physical activity are required for individuals living outside of this criterion.

A agricultura de corte e queima é praticada há milhares de anos nas áreas florestadas do planeta, principalmente nas regiões tropicais. Sua prática envolve uma gama de técnicas que denotam seu caráter diversificado e itinerante, aproveitando o capital energético da floresta em recomposição. Muitos estudos atestam a sustentabilidade desses sistemas quando praticados tradicionalmente e sob baixas densidades populacionais, mantendo, ou mesmo, promovendo a biodiversidade local e garantindo a subsistência de muitas populações pobres rurais. No entanto, é crescente na literatura acadêmica e no debate político o papel que a agricultura de corte e queima vem desempenhando no desmatamento e demais impactos ambientais e socioeconômicos. Esse processo é conseqüência das mudanças no uso do solo, da intensificação agrícola e do aumento demográfico que, estão alterando as práticas e comprometendo a sustentabilidade desses sistemas agrícolas tradicionais. No rastro dessas preocupações, este estudo traz uma revisão do tema na literatura com os objetivos de traçar um panorama geral do que foi produzido até o momento, identificar as principais correntes teóricas envolvidas e apontar as alternativas propostas para sua manutenção.

Este estudo tem como objetivos caracterizar o perfil demográfico e socioeconômico de nove comunidades remanescentes de quilombos no vale do Ribeira, estado de São Paulo, e identificar os principais fatores responsáveis pelas mudanças recentes nos seus padrões de subsistência. Desde a formação das primeiras aglomerações de escravos libertos e foragidos no século XVIII, as relações estabelecidas entre estas populações com as cidades próximas e com o mercado regional têm vivenciado momentos de retração e de expansão, adaptando-se e ajustando-se a novas mudanças políticas e socioeconômicas. Nas últimas cinco décadas, o impacto de fatores externos na aceleração das mudanças nos padrões de subsistência locais parece ter tido um aumento significativo. Os resultados mostram que as restrições impostas pela legislação ambiental, os conflitos de terra, a construção de uma rodovia na região, a crescente inserção no mercado regional e a atuação de órgãos governamentais e não-governamentais de desenvolvimento são os principais fatores responsáveis pelas mudanças observadas no sistema agrícola de corte e queima e, conseqüentemente, na organização socioeconômica destas populações.

O advento dos codigos no direito antigo

In the 1980s, growing recognition of agricultural phosphorus (P) sources to surface water eutrophication led to scrutiny of animal feeding operations. In 1990, the USDA-Natural Resources Conservation Service (NRCS) invited prominent scientists to find a solution. It was at an initial meeting that Dr. Andrew Sharpley suggested that P assessment could be modeled after the Universal Soil Loss Equation, where a matrix of factors influencing P loss would be associated with farm nutrient management recommendations. After codifying the P assessment into the USDA-NRCS 590 Nutrient Management Standard some 10 years later, 48 states chose to develop their own P Index. Sharpley, working with many others, helped develop several state P Indices. In 2000, Sharpley secured funding from the USDA-Agricultural Research Service to support the National P Research Project, which conducted in-field P runoff assessments using standardized rainfall simulated studies across 20 states; this allowed individual trials to be aggregated for agroecological regions that were then incorporated into specific state P Indices. Eventually, comparison of P Indices across state boundaries led to a white paper at the behest of USDA-NRCS that resulted in three regional projects evaluating modeling approaches to support or replace P Indices. Sharpley's national umbrella project pointed to shortcomings in water quality models, such as APEX or TBET, as a replacement for state P Indices, which remain a key part of the USDA-590 standard. As a selfless leader, capable of attracting and assembling diverse, productive interdisciplinary teams, Sharpley was essential to the inception, development, and implementation of the P Index., (© 2024 The Authors. Journal of Environmental Quality © 2023 American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.)

Phosphorus (P) fertilization practices and winter cover crops are promoted to protect water quality yet can potentially influence crop yield and profitability. This study examined the impacts of three P fertilizer management practices (no P, fall broadcast P, and spring injected P) and winter annual cover crop use on yields, net returns, and water quality in a no-till corn-soybean rotation. Treatments were replicated in a 4-yr field study where sediment, total P, and dissolved reactive P (DRP) losses in edge-of-field surface runoff were continuously monitored. Production budgets were developed for each treatment and coupled with water quality data to identify optimal practices and opportunity costs for improving water quality. Applying P fertilizers increased crop yield regardless of application method or cover crop, but the response was more pronounced in corn than soybean. The cover crop reduced corn grain yield in 1 yr with high temperature and low precipitation but did not impact grain yield in the other corn year or either year of soybean. The most profitable treatment was fall broadcast P fertilizer with no cover crop, which also had the greatest total P and DRP losses and near greatest sediment loss. The lowest-cost methods of reducing total P, DRP, and sediment losses were, respectively, no P fertilizer without a cover crop ($47.56 kg -1 total P), spring injected P fertilizer without a cover crop ($56.47 kg -1 DRP), and spring injected P fertilizer with a cover crop ($0.16 kg -1 sediment). Widespread adoption of these practices will likely require monetary incentives., (© 2022 The Authors. Journal of Environmental Quality published by Wiley Periodicals LLC on behalf of American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.)

Best management practices that reduce potential phosphorus (P) loss and provide flexibility in P fertilizer management are needed to help producers protect water quality while maintaining crop yield. This study examined the impacts of P fertilizer management (no P, fall broadcast P, and spring injected P) and cover crop use on annual concentrations and loads of sediment, total P, and dissolved reactive P (DRP) in edge-of-field runoff from a no-till corn (Zea mays)-soybean (Glycine max) rotation in the Central Great Plains, USA, from September 2015 through September 2019. The spring injected P fertilizer treatment generally had 19% less total P and 33% less DRP loss compared to the fall broadcast treatment, confirming the importance of P fertilizer management as a practice for reducing P loss. The addition of a cover crop had an inconsistent effect on total P loss, with no effect in 2016 and 2017, increasing loss in 2018 by 56%, and decreasing it in 2019 by 40%. The inconsistent impact of cover crops on total P loss was related to cover crop effects on sediment loss. Although cover crop impacts on total P losses were inconsistent, the addition of a cover crop increased DRP loss in three of four years. Cover crop use consistently reduced sediment loss, with greater sediment reduction when P fertilizer was applied. Results from this study highlight the benefit of cover crops for reducing sediment loss and the continued need for proper fertilizer management to reduce P loss from agricultural fields., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Cover crops are often recommended as a best management practice to reduce erosion, weed pressure, and nutrient loss. However, cover crops may be sources of phosphorus (P) to runoff water after termination. Two greenhouse trials were conducted to determine the effects of cover crop species, termination method, and time after termination on water-extractable P (WEP) release from crop biomass. Treatments were structured in a 3 × 3 × 3 factorial and arranged in a randomized complete block design with six replicates. Treatments included three cover crop species (triticale [× Triticosecale; Triticum × Secale 'Trical'], rapeseed [Brassica napus L. 'Winfred'], and crimson clover [Trifolium incarnatum L.]); three termination methods (clipping, freezing, and herbicide); and three WEP extraction times (1, 7, and 14 d after termination). Rapeseed consistently resulted in the least WEP when exposed to the same method of termination and at the same extraction time as the other species. For both trials, terminating crop tissue via freezing increased concentrations of WEP compared with other termination methods. The WEP release from cover crop tissue increased as the time after extraction increased, but the effect was greater for herbicide- and freeze-terminated cover crops and less for clipping-terminated cover crops. Future studies on WEP release from cover crops should pay close attention to the effects of extraction timing. Producers may be able to reduce P loss from cover crop tissue by selecting cover crop species with low WEP and minimizing the amount of biomass exposed to freezing conditions., (© 2019 The Authors. Journal of Environmental Quality © 2019 American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.)

Computer models are commonly used for predicting risks of runoff P loss from agricultural fields by enabling simulation of various management practices and climatic scenarios. For P loss models to be useful tools, however, they must accurately predict P loss for a wide range of climatic, physiographic, and land management conditions. A complicating factor in developing and evaluating P loss models is the relative scarcity of available measured field data that adequately capture P losses before and after implementing management practices in a variety of physiographic settings. Here, we describe the development of the P Loss in runoff Events from Agricultural fields Database (PLEAD)-a compilation of event-based, field-scale dissolved and/or total P loss runoff loadings from agricultural fields collected at various research sites located in the US Heartland and southern United States. The database also includes runoff and erosion rates; soil-test P; tillage practices; planting and harvesting rates and practices; fertilizer application rate, method, and timing; manure application rate, method, and timing; and livestock grazing density and timing. In total, >1800 individual runoff events-ranging in duration from 0.4 to 97 h-have been included in the database. Event runoff P losses ranged from <0.05 to 1.3 and 3.0 kg P ha for dissolved and total P, respectively. The data contained in this database have been used in multiple research studies to address important modeling questions relevant to P management planning. We provide these data to encourage additional studies by other researchers. The PLEAD database is available at ., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)

Phosphorus (P) Index assessment requires independent estimates of long-term average annual P loss from fields, representing multiple climatic scenarios, management practices, and landscape positions. Because currently available measured data are insufficient to evaluate P Index performance, calibrated and validated process-based models have been proposed as tools to generate the required data. The objectives of this research were to develop a regional parameterization for the Agricultural Policy Environmental eXtender (APEX) model to estimate edge-of-field runoff, sediment, and P losses in restricted-layer soils of Missouri and Kansas and to assess the performance of this parameterization using monitoring data from multiple sites in this region. Five site-specific calibrated models (SSCM) from within the region were used to develop a regionally calibrated model (RCM), which was further calibrated and validated with measured data. Performance of the RCM was similar to that of the SSCMs for runoff simulation and had Nash-Sutcliffe efficiency (NSE) > 0.72 and absolute percent bias (|PBIAS|) < 18% for both calibration and validation. The RCM could not simulate sediment loss (NSE < 0, |PBIAS| > 90%) and was particularly ineffective at simulating sediment loss from locations with small sediment loads. The RCM had acceptable performance for simulation of total P loss (NSE > 0.74, |PBIAS| < 30%) but underperformed the SSCMs. Total P-loss estimates should be used with caution due to poor simulation of sediment loss. Although we did not attain our goal of a robust regional parameterization of APEX for estimating sediment and total P losses, runoff estimates with the RCM were acceptable for P Index evaluation., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)

Over the past 20 yr, there has been a proliferation of phosphorus (P) site assessment tools for nutrient management planning, particularly in the United States. The 19 papers that make up this special section on P site assessment include decision support tools ranging from the P Index to fate-and-transport models to weather-forecast-based risk calculators. All require objective evaluation to ensure that they are effective in achieving intended benefits to protecting water quality. In the United States, efforts have been underway to compare, evaluate, and advance an array of P site assessment tools. Efforts to corroborate their performance using water quality monitoring data confirms previously documented discrepancies between different P site assessment tools but also highlights a surprisingly strong performance of many versions of the P Index as a predictor of water quality. At the same time, fate-and-transport models, often considered to be superior in their prediction of hydrology and water quality due to their complexity, reveal limitations when applied to site assessment. Indeed, one consistent theme from recent experience is the need to calibrate highly parameterized models. As P site assessment evolves, so too do routines representing important aspects of P cycling and transport. New classes of P site assessment tools are an opportunity to move P site assessment from general, strategic goals to web-based tools supporting daily, operational decisions., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)

Process-based computer models have been proposed as a tool to generate data for Phosphorus (P) Index assessment and development. Although models are commonly used to simulate P loss from agriculture using managements that are different from the calibration data, this use of models has not been fully tested. The objective of this study is to determine if the Agricultural Policy Environmental eXtender (APEX) model can accurately simulate runoff, sediment, total P, and dissolved P loss from 0.4 to 1.5 ha of agricultural fields with managements that are different from the calibration data. The APEX model was calibrated with field-scale data from eight different managements at two locations (management-specific models). The calibrated models were then validated, either with the same management used for calibration or with different managements. Location models were also developed by calibrating APEX with data from all managements. The management-specific models resulted in satisfactory performance when used to simulate runoff, total P, and dissolved P within their respective systems, with > 0.50, Nash-Sutcliffe efficiency > 0.30, and percent bias within ±35% for runoff and ±70% for total and dissolved P. When applied outside the calibration management, the management-specific models only met the minimum performance criteria in one-third of the tests. The location models had better model performance when applied across all managements compared with management-specific models. Our results suggest that models only be applied within the managements used for calibration and that data be included from multiple management systems for calibration when using models to assess management effects on P loss or evaluate P Indices., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)

The Agricultural Policy Environmental eXtender (APEX) model is capable of estimating edge-of-field water, nutrient, and sediment transport and is used to assess the environmental impacts of management practices. The current practice is to fully calibrate the model for each site simulation, a task that requires resources and data not always available. The objective of this study was to compare model performance for flow, sediment, and phosphorus transport under two parameterization schemes: a best professional judgment (BPJ) parameterization based on readily available data and a fully calibrated parameterization based on site-specific soil, weather, event flow, and water quality data. The analysis was conducted using 12 datasets at four locations representing poorly drained soils and row-crop production under different tillage systems. Model performance was based on the Nash-Sutcliffe efficiency (NSE), the coefficient of determination () and the regression slope between simulated and measured annualized loads across all site years. Although the BPJ model performance for flow was acceptable (NSE = 0.7) at the annual time step, calibration improved it (NSE = 0.9). Acceptable simulation of sediment and total phosphorus transport (NSE = 0.5 and 0.9, respectively) was obtained only after full calibration at each site. Given the unacceptable performance of the BPJ approach, uncalibrated use of APEX for planning or management purposes may be misleading. Model calibration with water quality data prior to using APEX for simulating sediment and total phosphorus loss is essential., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)

Most phosphorus (P) modeling studies of water quality have focused on surface runoff loses. However, a growing number of experimental studies have shown that P losses can occur in drainage water from artificially drained fields. In this review, we assess the applicability of nine models to predict this type of P loss. A model of P movement in artificially drained systems will likely need to account for the partitioning of water and P into runoff, macropore flow, and matrix flow. Within the soil profile, sorption and desorption of dissolved P and filtering of particulate P will be important. Eight models are reviewed (ADAPT, APEX, DRAINMOD, HSPF, HYDRUS, ICECREAMDB, PLEASE, and SWAT) along with P Indexes. Few of the models are designed to address P loss in drainage waters. Although the SWAT model has been used extensively for modeling P loss in runoff and includes tile drain flow, P losses are not simulated in tile drain flow. ADAPT, HSPF, and most P Indexes do not simulate flow to tiles or drains. DRAINMOD simulates drains but does not simulate P. The ICECREAMDB model from Sweden is an exception in that it is designed specifically for P losses in drainage water. This model seems to be a promising, parsimonious approach in simulating critical processes, but it needs to be tested. Field experiments using a nested, paired research design are needed to improve P models for artificially drained fields. Regardless of the model used, it is imperative that uncertainty in model predictions be assessed., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)

The P Index was proposed as a nutrient management tool in 1992 and has been implemented as such for the past decade. However, lack of water quality improvement in agricultural watersheds and discrepancies in P loss ratings between P indices have raised questions about continued use of the P Index. In response to these concerns, a symposium was held as part of the 2011 ASA, CSSA, SSSA annual meetings. This symposium produced a special collection of seven papers describing the role of P indices in P management, evaluation of P indices, new models for assessing P loss, methods to improve P indices, and changes in producer behavior resulting from P Index use. The objectives of this introductory paper are to provide background on the P Index concept, overviews of the special collection papers, and recommendations for future P Index evaluation and development research. The papers in this special collection conclude that P indices can provide accurate assessments of P loss but must be evaluated appropriately. Evaluation will require compiling large regional P loss datasets at field and small watershed scales. Simulation models may be used to generate P loss estimates; however, models must be calibrated and validated to ensure their accuracy. Further development of P indices will require coordinated regional efforts to identify common P Index frameworks and standardized interpretations. Stringent P Index evaluations will expand the utility of P indices for critical source area identification and strategic best management practice implementation by regulatory, education, and scientific communities alike., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)

Phosphorus release from stream sediments into water could increase P loads leaving agricultural watersheds and contribute to lag-time between implementation of best management practices and improvement in water quality. Improved understanding of P release from stream sediments can assist in setting water quality goals and designing stream monitoring programs. The objective of this study was to estimate the relative potential of sediments and soils to release P to stream water in two agricultural watersheds. Stream sediments were collected from banks, pools, riffles, and depositional features. Soils were sampled from wheat, row crop, pasture, and manure-amended fields. Sediments and soils were analyzed for equilibrium P concentration at zero net P sorption (EPC0), maximum P adsorption capacity (P(max)), anion exchange extractable P (P(lab)), and degree of P saturation. Dissolved reactive P (DRP) of stream water was monitored. Stream sediment EPC0 was similar to or less than EPC0 from field soils; however, P(lab) of stream sediments was three times less than field soils. Sediments were sandy and had low P(max) due to low oxalate-extractable Fe and Al, which could be explained by stream geomorphology. Manure-amended fields had the highest EPC0 and P(lab) due to continued inputs of manure-based P; however, conventionally fertilized fields also represented an important P source due to their vast extent. Stream water DRP was similar to EPC0 of sediments during base flow and similar to EPC0 of field soils during storm flow. These results indicate that sediments in these streams are a relatively minor P source.

Crop residue removal for expanded uses such as feedstocks for cellulosic ethanol production may increase loss of sediment and nutrients in runoff. We assessed on-farm impacts of variable rates of residue removal from no-till winter wheat (Triticum aestivum L.) and plow till grain sorghum [Sorghum bicolor (L.) Moench] on sediment, soil organic carbon (SOC) and nutrient losses in runoff in western Kansas. Five treatments with three replications consisting of removing residues at 0, 25, 50, 75, and 100% after harvest under two tillage levels for wheat (no-till and freshly tilled) and grain sorghum (spring tilled and freshly tilled) were established on 1x2 m plots. Simulated rainfall was applied at 115+/-3 mm h(-1) for 30 min. Compared with plots without residue removal, complete removal increased runoff by 61% in freshly tilled wheat plots, 225% in spring-tilled sorghum plots, and 94% in freshly tilled sorghum plots. Residue removal at rates as low as 50% increased loss of sediment. Complete removal doubled the sediment loss to 14 Mg ha(-1) in tilled wheat, whereas it increased sediment loss from 0.9 to 7.2 Mg ha(-1) in no-till wheat. No-till with 100% residue removal lost as much sediment as freshly tilled wheat plots with 0 or 25% removal. Residue removal at 75 and 100% increased losses of total N, total P, and SOC associated with sediment. Overall, excessive residue removal led to large losses of sediment, sediment-bound SOC, and nutrients in runoff. Furthermore, erosion protection provided by no-till management is lost when residue removal exceeds 25%.

Accurate descriptions of P leaching are important because excess P applied to soils can enter surface water via leaching and subsurface transport, thereby negatively impacting water quality. The objectives of this study were to monitor P leaching in soils with a long-term history of waste application, relate soil solution P concentrations to soil P status, and quantify P leaching losses. Soil solution was monitored for 20 mo with samplers installed at 45-, 90-, and 135-cm depths in two pits (1 x 3 x 1.5 m) in Autryville (loamy, siliceous, thermic Arenic Paleudults) and Blanton (loamy, siliceous, semiactive, thermic Grossarenic Paleudults) soils located in a grazed pasture in Sampson County, NC, which had received swine waste for >20 yr. Maximum soil solution P concentrations at 45 cm exceeded 18 mg L(-1) in both soils. Soil solution P concentrations at 90 cm in the Blanton soil were similar to that at 45 cm indicating low P sorption. Soil solution P concentrations at 90 cm in the Autryville soil averaged 0.05 mg L(-1) compared to 10 mg L(-1) at 45 cm. A split-line model related soil solution P concentration to the degree of phosphorus saturation (DPS), identifying a change point at 45% DPS. Phosphorus movement past 45 cm equaled or exceeded surplus P additions for both soils. Long-term waste applications resulted in DPS > 90%, high soil solution P concentrations, and substantial vertical P movement. Phosphorus leaching should be considered when assessing long-term risk of P loss from waste-amended soils.

Because of increased concern about surface water eutrophication from nutrient-enriched agricultural runoff, many swine producers are encouraged to decrease application rates of waste-based P. Precipitation and subsequent removal of magnesium ammonium phosphate (MgNH(4)PO(4) x 6H(2)O), commonly known as struvite, is a promising mechanism for N and P removal from anaerobic swine lagoon effluent. The objectives of this research were to (i) quantify the effects of adjusting pH and Mg:P ratio on struvite precipitation and (ii) determine the rate constant pH effect for struvite precipitation in anaerobic swine lagoon liquid. Concentrations of PO(4)-P in liquid from two anaerobic swine lagoons were determined after 24 h of equilibration for a pH range of 7.5-9.5 and Mg:P ratios between 1:1 and 1.6:1. Struvite formation reduced the PO(4)-P concentration in the effluents to as low as 2 mgl(-1). Minimum concentrations of PO(4)-P occurred between pH 8.9 and 9.25 at all Mg:P ratios. Struvite precipitation decreased PO(4)-P concentrations by 85% within 20 min at pH 9.0 for an initial Mg:P ratio of 1.2:1. The rate of PO(4)-P decrease was described by a first-order kinetic model, with rate constants of 3.7, 7.9, and 12.3 h(-1) at pH 8.4, 8.7 and 9.0 respectively. Our results indicate that induced struvite formation is a technically feasible method to remove N and P from swine lagoon liquid and it may allow swine producers to recover nutrients for off-farm sale.