Review of This Land: A Guide to Central National Forests by Robert H. Mohlenbrock

Robert Mohlenbrock's guide to the national forests of the central U.S. provides the traveling naturalist with a wealth of information on the wide array of national forest lands in the heart of the country. Part of a three-volume series of field guides, this volume covers the states of Louisiana, Minnesota, Missouri, Montana, Nebraska, New Mexico, South Dakota, Texas, and Wyoming. While most of the forests are along the western and eastern borders of the Great Plains, readers will find a detailed travelog for a National Forest within a day's drive of most areas within the region. While not the focus of this volume, a brief mention of the National Grasslands of the Great Plains would have made it more comprehensive for the traveling naturalist.

Evaluation of Attractants for Live-Trapping Nine-Banded Armadillos

In the past 50 years, the range of the nine-banded armadillo (Dasypus novemcinctus) in the south has been rapidly expanding. As their range expands, armadillos increasingly come into conflict with suburban landowners. When foraging, armadillos often uproot ornamental plants. Their rooting also destroys gardens, lawns, and flower beds. Their burrowing can damage tree roots and building foundations. Most armadillo damage is a result of their feeding habits. Armadillos dig shallow holes, 1- 3 inches deep and 3-5 inches long, as they search for soil invertebrates. A recent survey of Georgia county extension agents by scientists at the University of Georgia found that 77.6% of all agents reported receiving complaints or requests for information on armadillos. Armadillo related inquiries made up 10.1 % all inquiries for all agents across the state, surpassing even the white-tail deer (Odocoileus virginianus). Armadillos are often assumed to destroy nests of ground-nesting birds. Armadillo diets have been studied in several states including Alabama, Louisiana, Texas, Georgia, Arkansas, and Florida. According to these studies, vertebrate matter, especially bird eggs, made up an minor portion of their diet. The armadillo’s diet often consists of more than 90% insects, grubs and earthworms. Based on these studies, it seems that claims of armadillos being significant nest predators are unfounded.

NATIONWIDE ESTIMATES OF BLACKBIRDS AND STARLINGS

An estimated 538 million blackbirds and Starlings are found in the United States, based on the national cooperative blackbird/Starling winter roost survey conducted by the U.S. Fish and Wildlife Service during the 1974-75 winter period of December 20-February 15. Ap- proximately 74% or 398 million of these blackbirds and Starlings occurred in the Eastern States, including the tier from Minnesota to Louisiana; 26% or 139 million birds were in the West. The national roosting population in 1974-75 was composed of 11 species (Table 1) in the following approximate proportions: 38% Red-winged Blackbirds; 22% Common Grackles; 20% Starlings; 18% Brown-headed Cowbirds; 2% Brewer’s Blackbirds; and less than 1% six species combined (Rusty Blackbirds, Boat-tailed Grackles, Great-tailed Grackles, Tri-colored Black- birds, Yellow-headed Blackbirds, and Bronzed Cowbirds). (Some 2 million robins also were reported in the 1974-75 survey, though not solicited and therefore not tabulated, from 20 of the blackbird roosts in the Southeast.) The 1974-75 species proportions are similar to those found in the last nationwide winter survey (1969-70). In the 1963-64 national winter survey, Redwings made up 33% and Common Grackles 31% of the total population.

EXPERIMENTAL TREE TRIMMING TO CONTROL AN URBAN WINTER BLACKBIRD ROOST

Every fall millions of blackbirds come down the Mississippi Flyway to return to their winter roosts in Arkansas, Louisiana, and East Texas. When these roosts are located in urban areas, public pressure makes the more common chemical means of control impractical. A less destructive and more permanent method of control was sought. At Rice University, in Houston, Texas, there has been a blackbird roost of various sizes and durations since 1956. For the past two years we have had the opportunity both to study roosting blackbird biology and experiment with habitat alteration as a control method. This particular report concentrates on the results and interpretation of the tree- trimming program initiated in August 1974. The birds involved are primarily Brown-headed Cowbirds (Molothrus ater), along with Starlings (sturnus vulgaris), Common and Great-tailed Grackles (Quiscalus quiscula and Cassidix mexicanus), Red-winged Blackbirds (Agelaius phoenicus) and Robins (Turdus migratorius). The campus comprises 121 ha and was planted with live oaks (Quercus virginiana) in 1912. These trees retain their foliage throughout the winter and now form a closed canopy over some 5-6 ha. In the 60s and early 70s most of the birds that came to Houston for the winter roosted in a 64-ha woodlot 10 km north of campus. In January 1970, the U.S. Fish and Wildlife Roosting Survey reported one million birds at this site we call the North Loop. Fifteen- thousand birds were estimated at Rice.

AGRICULTURAL BIRD PROBLEMS IN THE SOUTHEAST

Our chairman has wisely asked that we not spend all of our time here telling each other about our bird problems. In the Southeast, our difficulties with blackbirds are based upon the same bird habits that cause trouble elsewhere: they flock, they roost and they eat, generally taking advantage of the readily available handouts that today's agricul¬tural practices provide. Those of us on the receiving end of these de¬predations of course think that damage in our own particular area must be far the worst, anywhere. Because of the location of our meeting place today, perhaps it is worthwhile to point out that a report prepared by our Bureau's Washington office this year outlined the problem of blackbird damage to corn in the Middle Atlantic States, the Great Lakes Region and in Florida, and then followed with this statement--"An equally serious problem occurs in rice and grain sorghum fields of Arkansas, Mississippi, Texas and Louisiana." The report also men¬tions that the largest winter concentrations of blackbirds are found in the lower Mississippi Valley. Our 1963-64 blackbird-starling survey showed 43 principal roosts totaling approximately 100 million of these birds in Virginia, the Carolinas, Georgia, Alabama, Tennessee and Kentucky. We have our own birds during the summer plus the "tourist" birds from up here and elsewhere during the winter, and all of these birds must eat, so suffice it to say that we, too, have some bird problems in the Southeast. I'm sure you're more interested in what we're doing about them. To keep this in perspective also, please bear in mind that against the magnitude of these problems, our blackbird control research staff at Gainesville consists of 3 biologists, 1 biochemist and one technician. And unfortunately, none of us happens to be a miracle worker. I think, though, we have made great progress toward solving the bird problems in the Southeast for the man-hours that have been expended in this re¬search. My only suggestion to those who are impatient about not having more answers is that they examine the budget that has been set up for this work. Only then could we intelligently discuss what might be expected as a reasonable rate of research progress. When I think about what we have accomplished in a short span of time, with very small expenditure, I can assure you that I am very proud of our small research crew at Gainesville--and I say this quite sincerely. At the Gainesville station, we work under two general research approaches to the bird damage problem. These projects have been assigned to us. The first is research on management of birds, particularly blackbirds and starlings destructive to crops or in feedlots, and, secondly, the development and the adaptation of those chemical compounds found to be toxic to birds but relatively safe to mammals. These approaches both require laboratory and field work that is further subdivided into several specific research projects. Without describing the details of these now, I want to mention some of our recent results. From the results, I'm sure you will gather the general objectives and some of the procedures used.

A biophysical model of Sugarcane growth

Scientists predict that global agricultural lands will expand over the next few decades due to increasing demands for food production and an exponential increase in crop-based biofuel production. These changes in land use will greatly impact biogeochemical and biogeophysical cycles across the globe. It is therefore important to develop models that can accurately simulate the interactions between the atmosphere and important crops. In this study, we develop and validate a new process-based sugarcane model (included as a module within the Agro-IBIS dynamic agro-ecosystem model) which can be applied at multiple spatial scales. At site level, the model systematically under/overestimated the daily sensible/latent heat flux (by -10.5% and 14.8%, H and E, respectively) when compared against the micrometeorological observations from southeast Brazil. The model underestimated ET (relative bias between -10.1% and 12.5%) when compared against an agro-meteorological field experiment from northeast Australia. At the regional level, the model accurately simulated average yield for the four largest mesoregions (clusters of municipalities) in the state of Sao Paulo, Brazil, over a period of 16 years, with a yield relative bias of -0.68% to 1.08%. Finally, the simulated annual average sugarcane yield over 31 years for the state of Louisiana (US) had a low relative bias (-2.67%), but exhibited a lower interannual variability than the observed yields.

Wildfire frecasting using an open source 3D multilayer geographical framework

[EN] This abstract describes the development of a wildfire forecasting plugin using Capaware. Capaware is designed as an easy to use open source framework to develop 3D graphics applications over large geographic areas offering high performance 3D visualization and powerful interaction tools for the Geographic Information Systems (GIS) community.

Modellazione bidimensionale della propagazione nell'entroterra della inondazione da mare negli scenari dei previsti cambiamenti climatici

Le ricerche di carattere eustatico, mareografico, climatico, archeologico e geocronologico, sviluppatesi soprattutto nell’ultimo ventennio, hanno messo in evidenza che gran parte delle piane costiere italiane risulta soggetta al rischio di allagamento per ingressione marina dovuta alla risalita relativa del livello medio del mare. Tale rischio è la conseguenza dell’interazione tra la presenza di elementi antropici e fenomeni di diversa natura, spesso difficilmente discriminabili e quantificabili, caratterizzati da magnitudo e velocità molto diverse tra loro. Tra le cause preponderanti che determinano l’ingressione marina possono essere individuati alcuni fenomeni naturali, climatici e geologici, i quali risultano fortemente influenzati dalle attività umane soprattutto a partire dal XX secolo. Tra questi si individuano: - la risalita del livello del mare, principalmente come conseguenza del superamento dell’ultimo acme glaciale e dello scioglimento delle grandi calotte continentali; - la subsidenza. Vaste porzioni delle piane costiere italiane risultano soggette a fenomeni di subsidenza. In certe zone questa assume proporzioni notevoli: per la fascia costiera emiliano-romagnola si registrano ratei compresi tra 1 e 3 cm/anno. Tale subsidenza è spesso il risultato della sovrapposizione tra fenomeni naturali (neotettonica, costipamento di sedimenti, ecc.) e fenomeni indotti dall’uomo (emungimenti delle falde idriche, sfruttamento di giacimenti metaniferi, escavazione di materiali per l’edilizia, ecc.); - terreni ad elevato contenuto organico: la presenza di depositi fortemente costipabili può causare la depressione del piano di campagna come conseguenza di abbassamenti del livello della falda superficiale (per drenaggi, opere di bonifica, emungimenti), dello sviluppo dei processi di ossidazione e decomposizione nei terreni stessi, del costipamento di questi sotto il proprio peso, della carenza di nuovi apporti solidi conseguente alla diminuita frequenza delle esondazioni dei corsi d’acqua; - morfologia: tra i fattori di rischio rientra l’assetto morfologico della piana e, in particolare il tipo di costa (lidi, spiagge, cordoni dunari in smantellamento, ecc. ), la presenza di aree depresse o comunque vicine al livello del mare (fino a 1-2 m s.l.m.), le caratteristiche dei fondali antistanti (batimetria, profilo trasversale, granulometria dei sedimenti, barre sommerse, assenza di barriere biologiche, ecc.); - stato della linea di costa in termini di processi erosivi dovuti ad attività umane (urbanizzazione del litorale, prelievo inerti, costruzione di barriere, ecc.) o alle dinamiche idro-sedimentarie naturali cui risulta soggetta (correnti litoranee, apporti di materiale, ecc. ). Scopo del presente studio è quello di valutare la probabilità di ingressione del mare nel tratto costiero emiliano-romagnolo del Lido delle Nazioni, la velocità di propagazione del fronte d’onda, facendo riferimento allo schema idraulico del crollo di una diga su letto asciutto (problema di Riemann) basato sul metodo delle caratteristiche, e di modellare la propagazione dell’inondazione nell’entroterra, conseguente all’innalzamento del medio mare . Per simulare tale processo è stato utilizzato il complesso codice di calcolo bidimensionale Mike 21. La fase iniziale di tale lavoro ha comportato la raccolta ed elaborazione mediante sistema Arcgis dei dati LIDAR ed idrografici multibeam , grazie ai quali si è provveduto a ricostruire la topo-batimetria di dettaglio della zona esaminata. Nel primo capitolo è stato sviluppato il problema del cambiamento climatico globale in atto e della conseguente variazione del livello marino che, secondo quanto riportato dall’IPCC nel rapporto del 2007, dovrebbe aumentare al 2100 mediamente tra i 28 ed i 43 cm. Nel secondo e terzo capitolo è stata effettuata un’analisi bibliografica delle metodologie per la modellazione della propagazione delle onde a fronte ripido con particolare attenzione ai fenomeni di breaching delle difese rigide ed ambientali. Sono state studiate le fenomenologie che possono inficiare la stabilità dei rilevati arginali, realizzati sia in corrispondenza dei corsi d’acqua, sia in corrispondenza del mare, a discapito della protezione idraulica del territorio ovvero dell’incolumità fisica dell’uomo e dei territori in cui esso vive e produce. In un rilevato arginale, quale che sia la causa innescante la formazione di breccia, la generazione di un’onda di piena conseguente la rottura è sempre determinata da un’azione erosiva (seepage o overtopping) esercitata dall’acqua sui materiali sciolti costituenti il corpo del rilevato. Perciò gran parte dello studio in materia di brecce arginali è incentrato sulla ricostruzione di siffatti eventi di rottura. Nel quarto capitolo è stata calcolata la probabilità, in 5 anni, di avere un allagamento nella zona di interesse e la velocità di propagazione del fronte d’onda. Inoltre è stata effettuata un’analisi delle condizioni meteo marine attuali (clima ondoso, livelli del mare e correnti) al largo della costa emiliano-romagnola, le cui problematiche e linee di intervento per la difesa sono descritte nel quinto capitolo, con particolare riferimento alla costa ferrarese, oggetto negli ultimi anni di continui interventi antropici. Introdotto il sistema Gis e le sue caratteristiche, si è passati a descrivere le varie fasi che hanno permesso di avere in output il file delle coordinate x, y, z dei punti significativi della costa, indispensabili al fine della simulazione Mike 21, le cui proprietà sono sviluppate nel sesto capitolo.

Stato ecologico di Punte Alberete e Valle Mandriole: popolamenti macrozoobentonici e chimica delle acque

Il presente studio si è proposto di fornire un contributo per la definizione dello stato ecologico delle zone umide d’acqua dolce ravennati (Punte Alberete, Valle Mandriole e uno stagno temporaneo creatosi nella limitrofa Pineta di San Vitale), attraverso lo studio della fauna macrobentonica presente nei sedimenti e nella vegetazione emergente. Sono stati prelevati campioni d’acqua con lo scopo di analizzare alcuni parametri chimico fisici, per relazionarli con i dati ecologici sulle comunità oggetto di studio. Inoltre è stato valutato il potenziale effetto sulle comunità macrozoobentoniche della attuale gestione di Valle Mandriole, che prevede il prosciugamento estivo della zona meridionale al fine di consentire operazioni di sflacio della vegetazione. Per valutare questo tipo di impatto è stato applicato un disegno di campionamento di tipo Beyond-BACI. Sono stati definiti quattro siti di controllo ed un sito potenzialmente impattato. Sono stati definiti due punti di campionamento su ciascun sito e sono stati campionati in totale quattro volte ciascuno, due volte prima del periodo estivo, corrispondente alla messa in secca del sito impattato, e due volte in autunno. I dati raccolti sul benthos e sulle acque sono poi stati analizzati attraverso l’analisi statistica multivariata PERMANOVA. I risultati dei test statistici non hanno rilevato nessun tipo di impatto associabile alla pratica di gestione attuata a Valle Mandriole, mentre l’analisi delle comunità macrozoobentoniche ha evidenziato, attraverso confronti temporali con dati storici e con altri studi, una situazione di degrado dal punto di vista delle stato ecologico di Punte Alberete e Valle Mandriole, molto probabilmente associabile all’abbondante presenza del gambero della Louisiana. La condizione di stato ecologico non soddisfacente può oltretutto essere imputabile anche alla qualità ecologica scarsa dei corsi d’acqua deputati al ricarico delle zone umide considerate. Lo studio ha inoltre sottolineato l’importanza dal punto di vista conservazionistico dello stagno in Pineta San Vitale.

Repeat chlamydia screening among adolescents: cohort study in a school-based programme in New Orleans

OBJECTIVES To describe uptake of chlamydia screening, determine rates of repeated yearly screening and investigate determinants of repeated participation in an organised school-based screening programme. METHODS The authors analysed data from 1995 to 2005 from female and male students in up to 13 schools in New Orleans, Louisiana, USA. The authors calculated proportions of students tested among all enrolled students and among those with parental consent and the percentage of positive chlamydia tests in each school year. The authors used random effects logistic regression to examine the effect of past screening history on subsequent participation. RESULTS 35 041 students were registered for at least one school year. Overall coverage was >30% in all school years. Among all students registered for 4 years, 10.6% (95% CI 9.3% to 12.0%) of women and 12.7% (95% CI 11.2% to 14.2%) of men had a test every year. Among students with parental consent for 4 years, 49.3% (95% CI 44.6% to 54.1%) of women and 59.3% (95% CI 54.5% to 64.0%) of men had a test every year. Among students registered for 2 or more years, those with a previous positive chlamydia test were less likely to have a subsequent test (female adjusted OR 0.77, 95% CI 0.67 to 0.88 and male adjusted OR 0.84, 95% CI 0.69 to 1.02). Chlamydia positivity increased over time. CONCLUSIONS High levels of uptake can be achieved in school-based chlamydia screening programmes, but repeated yearly screening is difficult to sustain over time.

Hormonal risk factors and testicular cancer

The cause of testicular cancer is not known and recent hypotheses have suggested an altered hormonal milieu may increase the risk of testis cancer. This study examined modulation of testicular cancer risk by hormonal factors, specifically: environmental xenoestrogens (e.g. organochlorines), prenatal maternal estrogens, testosterone indices (age at puberty, severe adolescent acne, self-reported balding), sedentary lifestyle and dietary consumption of fats and phytoestrogens.^ A hospital based friend matched case-control study was conducted at the University of Texas M. D. Anderson Cancer Center in Houston, Texas, between January 1990 and October 1996. Cases had a first primary testis tumor diagnosed between age 18 to 50 years and resided in Texas, Louisiana, Oklahoma or Arkansas.^ Cases and friend controls completed a mail questionnaire and case/control mothers were contacted by phone regarding pregnancy related variables. The study population comprised 187 cases, 148 controls, 147 case mothers and 86 control mothers. Odds ratios were virtually identical whether the match was retained or dissolved, thus the analyses were conducted using unconditional logistic regression.^ Cryptorchidism was a strong risk factor for testis cancer with an age-adjusted odds ratio (OR) of 7.7 (95% confidence interval (CI): 2.3-26.3). In a final model (adjusted for age, education, and cryptorchidism), history of severe adolescent acne and self-reported balding were both significantly protective, as hypothesized. For acne (yes vs. no) the OR was 0.5 (CI: 0.3-1.0) and for balding (yes vs. no) the OR was 0.6 (CI: 0.3-1.0). Marijuana smoking was a risk factor among heavy, regular users (17 times/week, OR = 2.4; CI: 0.9-6.4) and higher saturated fat intake increased testis cancer risk (saturated fat intake $>$ 15.2 grams/day vs. $<$ 11.8 grams/day, OR = 3.3; CI: 1.5-7.1). Early puberty, xenoestrogen exposure, elevated maternal estrogen levels, sedentary lifestyle and dietary phytoestrogen intake were not associated with risk of testicular cancer.^ In conclusion, testicular cancer may be associated with endogenous androgen metabolism although environmental estrogen exposure can not be ruled out. Further research is needed to understand the underlying hormonal mechanisms and possible dietary influences. ^

A MORTALITY STUDY OF BUTYL-CHLOROBUTYL RUBBER WORKERS

Worker populations are potentially exposed to multiple chemical substances simultaneously during the performance of routine tasks. The acute health effects from exposure to toxic concentrations of these substances are usually well-described. However, very little is known about the long-term health effects of chronic low dose exposure to all except a few chemical substances. A mortality study was performed on a population of workers employed at a butyl rubber manufacturing plant in Baton Rouge, Louisiana for the period 1943-1978, with special emphasis on potential exposure to methyl chloride.^ The study population was enumerated using company records. The mortality experience among the population was evaluated by comparing the number of observed deaths (total and cause-specific) to the expected number of deaths, based on the U.S. general age, race, sex specific rates. An internal comparison population was assembled to address the issue of lack of comparability when the U.S. rates are used to calculate expected deaths in an employed population.^ There were 18% fewer total observed deaths compared to the expected when the U.S. death rates were used to obtain the expected. Deaths from specific causes were also less than expected except when numbers of observed and expected deaths were small. Similar results were obtained when the population was characterized by intensity and duration of potential exposure to methyl chloride. When the internal comparison population was utilized to evaluate overall mortality of the study population, the relative risk was about 1.2.^ The study results were discussed and conclusions drawn in light of certain limitations of the methodology and study population size. ^

A cohort study of occupational asbestos-exposure related neoplasms in Texas Gulf Coast area

A cohort study was conducted in Texas and Louisiana Gulf Coast area on individual workers who have been exposed to asbestos for 15 years or more. Most of these workers were employed in petrochemical industries. Of the 15,742 subjects initially selected for the cohort study, 3,258 had positive chest X-ray findings believed to be related to prolonged asbestos exposure. These subjects were further investigated. Their work out included detailed medical and occupational history, laboratory tests and spirometry. One thousand eight-hundred and three cases with positive chest X-ray findings whose data files were considered complete at the end of May 1986 were analyzed and their findings included in this report.^ The prevalence of lung cancer and cancer of the following sights: skin, stomach, oropharyngeal, pancreas and kidneys were significantly increased when compared to data from Connecticut Tumor Registry. The prevalence of other chronic conditions such as hypertension, emphysema, heart disease and peptic ulcer was also significantly high when compared to data for the U.S. and general population furnished by the National Center for Health Statistics (NCHS). In most instances the occurrence of cancer and the chronic ailment previously mentioned appeared to follow 15-25 years of exposure to asbestos. ^