Biomass harvest of invasive Typha promotes plant diversity in a Great Lakes coastal wetland

Ecological and financial constraints limit restoration efforts, preventing the achievement of desired ecological outcomes. Harvesting invasive plant biomass for bioenergy has the potential to reduce feedback mechanisms that sustain invasion, while alleviating financial limitations. Typha × glauca is a highly productive invasive wetland plant that reduces plant diversity, alters ecological functioning, its impacts increase with time, and is a suitable feedstock for bioenergy. We sought to determine ecological effects of Typha utilization for bioenergy in a Great Lakes coastal wetland by testing plant community responses to harvest‐restoration treatments in stands of 2 age classes and assessing community resilience through a seed bank study. Belowground harvesting increased light penetration, diversity, and richness and decreased Typha dominance and biomass in both years post‐treatment. Aboveground harvesting increased light and reduced Typha biomass in post‐year 1 and in post‐year 2, increased diversity and richness and decreased Typha dominance. Seed bank analysis revealed that young stands (<20 years) had greater diversity, richness, seedling density, and floristic quality than old stands (>30 years). In the field, stand‐age did not affect diversity or Typha dominance, but old stands had greater Typha biomass and slightly higher richness following harvest. Harvesting Typha achieved at least 2 desirable ecological outcomes: reducing Typha dominance and increasing native plant diversity. Younger stands had greater potential for native recovery, indicated by more diverse seed banks. In similar degraded wetlands, a single harvest of Typha biomass would likely result in significant biodiversity and habitat improvements, with the potential to double plant species richness.     

THE EXPERIMENTAL DEMONSTRATION OF PRE-MIGRATION ACTIVITY IN THE ABSENCE OF FAT DEPOSITION IN BIRDS

Under dietary conditions that experimentally prevented the accumulation of "pre-migratory" depot fat, typical nocturnal migratory restlessness developed in the Brambling Fringilla montifringilla. Subsidiary data are presented from Junco hyemalis and Zonotrichia albicollis.
In captive controls, the rapid accumulation and subsequent utilization of body fat closely paralleled the onset and waning of nocturnal unrest.
Although the Brambling accumulates fat reserves before both nuptial and contra-nuptial flights, it would seem that the presence of such is not an essential element of the so-called "total physiological state" necessary for the onset of migration.     

Some observations on the physiological effects of gaseous ions

This paper reviews some of the evidence pertaining to the biological effects of gaseous ions. It appears to us that experimental data now available warrant the conclusion that reproducible biological effects occur in a variety of living forms including microorganisms, higher plants, insects, animals and man. The responses generally are limited in extent and to indict air ions as their sole cause requires great care in defining the experimental conditions. Some progress has been made in detecting the fundamental biochemical reactions associated with ion-induced physiological changes. The ready availability of excellent apparatus for generation and measurement of air-ions, coupled with present-day knowledge about their properties, makes critical experimentation possible.