Ammonia-oxidizing bacteria and ammonia-oxidizing archaea are commonly found together in soils, yet the factors influencing their relative distribution and activity remain unclear. We examined archaeal and bacterial amoA gene distribution, and used a novel bioassay to assess archaeal and bacterial contributions to nitrification potentials in soils spanning a range of land uses (forest, pasture, ...

The movement of frugivores between remnant forests and successional areas is vital for tropical forest tree species to colonize successional habitats. The response of these species to the spatial structure of pasture tree cover is largely unknown. We studied avian frugivores that were found in primary forest edges and large pastures in eastern Amazonia, Brazil. We determined how the small-scale...

Four studies were conducted to a similar experimental design in the U.S. to evaluate the effectiveness of doramectin injectable administered to yearling stocker cattle in the control of gastrointestinal nematodiasis over the subsequent grazing period. Studies were conducted in Wisconsin (WI) and Arkansas (AR) during the summer season. The other two studies were conducted in Georgia (GA) and Mis...

Members of the phylum Acidobacteria are among the most abundant soil bacteria on Earth, but little is known about their response to environmental changes. We asked how the relative abundance and biogeographic patterning of this phylum and its subgroups responded to forest-to-pasture conversion in soils of the western Brazilian Amazon. Pyrosequencing of 16S rRNA genes was employed to assess the ...

Milk production of fall-calving dairy cows during subsequent summer grazing was evaluated in two consecutive years using a total of 80 mid- to late-lactation Holsteins. Cows calved during September and October and grazed from April to August in the following year. In yr 1, 27 cows grazed a native grass pasture and 13 cows grazed a native grass-clover mixed pasture containing 26% red clover and ...

Successful pasture-based milk production systems pivot on balancing dairy cows’ feed requirements with seasonal and annual fluctuations in pasture production. In order to maximise cow production from grazing dairy systems, it is necessary to reach an efficient utilization of grazed grass for feeding cows and the development of appropriate grazing management systems designed to maximize daily pa...

Winter is a very important period during the dairying calendar. Regions such as Southland, with susceptible soils and extended periods with soils at saturation levels will face increasing pressure to review wintering practices. On-farm options for wintering cows to protect soils and prevent pasture damage are needed. This requires a turn-around in philosophy from taking cows to pasture/crops, t...

1 2 A soil transfer field experiment has been designed in order to study (i) whether and how 3 Collembolan communities are affected by a sudden perturbation (a shift from agricultural land 4 to heathland, and the reverse), and (ii) whether species do respond in the same direction and 5 to the same extent according to their habitat preference (ascertained by controls). The study 6 was conducted ...

Introduction Cattle production on Brachiaria pastures is a primary use of cleared forestland in the western Brazilian Amazon. About 6.8 million hectares in the States of Acre and Rondônia have been deforested, where 75% of land is now grazed (IBGE, 1998). The principal pasture species are B. brizantha and B. decumbens with the latter in decline from spittlebug susceptibility (Deois incompleta; ...