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Healthy soil biota is the key to meeting the world population’s growing demand for food, energy, fiber and raw materials. Our aim is to investigate the effect of green manure as a strategy to recover the macrofauna and the chemical properties of soils which have been anthropogenically degraded. The experiment was a completely randomized block design with four replicates. Green manure, Urochloa decumbens, with or without application of limestone and gypsum, composed the integrated systems. The macroorganisms as well as the soil fertility were analyzed after 17 years of a process of soil restoration with the aforementioned systems. The succession of Stizolobium sp. with Urochloa decumbens, with limestone and gypsum, was teeming with termites, beetles and ants. This integrated system presented the most technically adequate indexes of diversity and uniformity. Multivariate models showed a substantial increase in the total number of individuals due to the neutralization of harmful elements and the gradual release of nutrients by limestone and plaster. These conditioners have undergone multiple chemical reactions with the substrate in order to balance it chemically, thus allowing the macroinvertebrates to grow, develop, reproduce and compose their food web in milder microclimates. It was concluded that the integration of green manure together with grass is an economical and environmentally correct strategy to restore the macrofauna properties of degraded soil in the Brazilian savannah.

Un factor determinante en la disminución del rendimiento de la cebolla (Allium cepa L.) es la enfermedad raíz roja causada por Pyrenochaeta terrestris. Una alternativa en el control de esta enfermedad es la solarización del suelo, la cual constituye una medida erradicativa de patógenos. En un ensayo de campo llevado a cabo en suelo naturalmente infestado con Pyrenochaeta terrestris (Hansen) en Quíbor, estado Lara, Venezuela, se evaluó el efecto de la solarización (calentamiento del suelo por medio de su cubrimiento con láminas plásticas transparentes), adición de abonos verdes y la combinación de ambos tratamientos sobre la incidencia y la severidad de la raíz roja en cebolla. Se utilizó un diseño experimental en bloques al azar con seis repeticiones y un arreglo en parcelas divididas, en donde en las parcelas principales fueron ubicados los tratamientos de solarizado y no solarizado y en las subparcelas los abonos verdes (canavalia, Canavalia sp.; crotalaria, Crotalaria sp. y soya, Glycine max L.). La cobertura del suelo durante 45 días redujo la incidencia y la severidad de la enfermedad; en el suelo solarizado la incidencia fue 18,16 % y en el no solarizado fue 52,33 %, diferencia que representa un 65,29 % de control de la enfermedad. Con respecto a la severidad, hubo una reducción cercana al 12 % con la solarización. Las temperaturas logradas en el suelo solarizado fueron 4,6-10,9 °C mayores a las del suelo no solarizado. La solarización del suelo por sí sola fue efectiva para el control de la raíz roja, y la aplicación de abonos verdes no agregó ningún efecto sobre este control. A determining factor in the decrease in the yield of onion (Allium cepa L.) is the pink root disease caused by Pyrenochaeta terrestris (Hansen). An alternative in the control of this disease is the solarization of soil, which is an erradicative measure of pathogens. A field experiment was carried out in naturally infested soil with Pyrenochaeta terrestris in Quíbor, Lara State, Venezuela, to determine the effect of solar heating in the soil by means of mulching with transparent polyethylene sheets, green manure applications, and combination of both treatments on the incidence and severity of onion pink root disease. A split-plot experiment was conduced, where main plots comprised those with presence and absence of solarization, and subplots were a factorial combination of green manure (Canavalia sp., Crotalaria sp., Glycine max L.) with and without solarization. There were six replications. The mulching of the soil with transparent polyethylene sheets for 45 days resulted in a decrease of the incidence and severity of disease, in solarized soil the incidence was 18.16 % and in non solarized soil was 52.33 %; this difference represents 65.29 % of disease control. With respect to the severity, there was a reduction close to 12% with solarization. Soil temperatures in the mulched soil varied from 4.6 to 10.9 °C higher than in unmulched soil. Soil solarization was effective for the control of pink root, and green manure application did not provide any additional effect for the disease control.

The Roosevelt Community Development Study (RCD) involved the testing and excavation of 27 sites in the Lower Tonto Basin of central Arizona. This is one of three related data recovery projects undertaken in the Tonto Basin for the Bureau of Reclamation prior to the raising of the Roosevelt Lake dam. The results of the RCD project are presented in four Anthropological Papers of the Center for Desert Archaeology: Anthropological Papers No. 12 is the research design; Anthropological Papers No. 13 (two volumes) contains background information and the site descriptions; Anthropological Papers No. 14 (three volumes) includes the artifact and environmental analyses; and Anthropological Papers No. 15 presents the synthesis and conclusions. The project was situated within the Tonto National Forest and covered a four-mile, continuous area along the north bank of the Salt River. Sites within the project area exhibited a great range of functional, temporal, and, possibly, cultural diversity. These included two sites with platform mounds (the Meddler Point and Pyramid Point sites); a 10Q-room masonry pueblo (the Griffin Wash site); smaller masonry compounds (e.g., the Porcupine site); and pithouse hamlets and farmsteads (e.g., the Hedge Apple and Eagle Ridge sites). Temporal components ranged from the Early Ceramic period (A.D. 100-600), at Locus B of the Eagle Ridge site, through the Roosevelt phase (A.D. 1250-1350) of the Classic period. The Early Ceramic component of the Eagle Ridge site is now the earliest documented ceramic period site in the Tonto Basin and provides definitive evidence for an indigenous ceramic-using population. The project area was inhabited most intensively during the Roosevelt phase, when platform mounds, pueblo room blocks, and small masonry compounds were occupied. Architectural and artifact variability suggest the presence of several different cultural groups co-residing in the Tonto Basin at this time, and migration is believed to have been a significant process in Tonto Basin prehistory. The RCD project area was largely abandoned by A.D. 1325, prior to the large-scale aggregation that occurred during the Gila phase; very few Gila Polychrome sherds were recovered from project area sites. The mandate of the RCD project, as spedfied by the Bureau of Reclamation, was to investigate the temporal and developmental sequence of the prehistoric populations within this area. To meet these goals, six sites were intensively examined through full-scale excavation, and an extensive data set was gathered from the remaining 21 sites. The three volumes in Anthropological Papers No. 14 contain the artifact and environmental analyses. More than 150,000 artifacts were recovered from the RCD excavations. This volume (Volume 3) presents the paleobotanical and osteological data. Included are analyses of the pollen (Chapter 18), flotation (Chapter 19), faunal (Chapter 20), and mortuary (Chapter 21) assemblages. Data from the subsistence analyses are combined and synthesized in Chapter 22. Volume 1 of Anthropological Papers No. 14 presents the analyses of the chipped stone, ground stone, jewelry and personal ornament, and shell assemblages. The ceramic artifact assemblage is examined in Volume 2 More spedfic information on the individual sites and the project background can be found in Anthropological Papers No. 13. Anthropological Papers No. 15 integrates and synthesizes these data to provide a more inclusive view of the prehistoric occupation of the RCD project area and the Tonto Basin.