Plant genetic variation and evolutionary dynamics are predicted to impact ecosystem processes but these effects are poorly understood. Here we test the hypothesis that plant genotype and contemporary evolution influence the flux of energy and nutrients through soil, which then feedback to affect seedling performance in subsequent generations. We conducted a multiyear field evolution experiment ...

Plant community composition can impact ecosystem processes via litter feedbacks. Species variation in litter quality may generate diff erent patterns of nutrient supply for plants that are dependent on litter inputs. However, it is not known whether plants grow faster in their own litter, litter from other species, or in litter mixtures from multiple species. To test whether litter identity and...

The relative importance of livestock grazing in limiting or enhancing oak recruitment remains unclear because results from previous studies have been contradictory. In Santa Barbara County, we have replicated large-scale planting experiments from 1997 to 2001 to determine the effects of cattle and other factors on seedling establishment of valley oak (Quercus lobata) and coast live oak (Q. agri...

Herbivory by rodents, lagomorphs and insects may locally constrain woody plant seedling establishment and stand development. Recruitment may therefore depend either upon plant tolerance of herbivory, or low herbivore abundance, during seedling establishment. We tested potential herbivory tolerance by quantifying growth, biomass allocation, and survival of defoliated Prosopis glandulosa seedling...

High fertilizer application and over-irrigation in sugarcane systems can cause considerable N2O emissions. Optimized water-fertilization management which reduces emissions, while maintaining biomass, is crucial, but may affect nitrogen fixation by sugarcane. This study evaluated the combined effect of on biomass field trials southern China. Treatments included drip spray irrigation, with three ...

Artemisia monosperma is observed to be as one of the first species to dominate disturbed sand dunes in Saudi Arabia. Despite its importance as a sand stabilizer, it has no forage value. It is feared that this species may arrest the natural succession of vegetation. A series of controlled environment experiments was conducted to study the potential allelopathic effects of A. monosperma on germin...

Increasing environmental concerns and growing demand for safer and sustainable food production presents significant challenges for agricultural production. One potential technique, which could help improve crop productivity without adverse impact on the environment, is the use of beneficial microbes in crop production systems. This study evaluated the effects of three Azospirillum brasilense st...

Pseudobombax tomentosum and P. longiflorum are common trees in the Cerrado region, but the former species is more common in forest edges while the later is present in open cerrado areas. This work aimed to investigate differences in seed germination and seedling growth in these species, from seed collected from Cerrado areas in Central Brazil. For this, a seed germination experiment was designe...

Seed germination, seedling emergence and crop establishment are important aspects of canola production, and are the main components of seed/seedling vigour. A major concern of seed businesses and canola growers alike is loss of seed vigour that may go undetected before planting. Two vigour assays, based on off-gassing of ethyl alcohol from poor vigour seed, are being developed. They are a simpl...

Changes in tree species distributions are a potential impact of climate change on forest ecosystems. The examination of tree species shifts in forests of the eastern United States largely has been limited to simulation activities due to a lack of consistent, long-term forest inventory datasets. The goal of this study was to compare current geographic distributions of tree seedlings (trees with ...