Treesearch

The Rough Fire started on 31 July 2015 from a lightning strike, spread to over 61,000 ha and burned parts of the Sierra and Sequoia National Forests and the Sequoia & Kings Canyon National Parks, in California. Health advisories for smoke were issued in rural areas around the fire and in urban areas of the Central Valley. PM2.5 concentrations in rural and urban areas were used to assess the air quality impacts from the fire. Before the Rough Fire, 24-h PM2.5 concentrations for all sites ranged from 1 µg m−3o 50 µgm−3. During the wildfire, the 24-h PM2.5 concentrations ranged from 2 µgm−3to...

1. Despite theoretical advances, the ecological factors and functional traits that enable species varying in seed size and fecundity to coexist remain unclear. Given inherent fecundity advantages, why don't small-seeded species dominate communities?2. In perennial grasslands, we evaluated whether small-seeded species are less tolerant of competition from the community dominant bunchgrass than large-seeded species, but also less vulnerable to seed predation by mice. We also explored whether trade-offs involving competitive tolerance include two other functional traits, height and leaf mass...

Capsule: In a single-year study, attaching geolocators to male Prairie Warblers Setophaga discolor, one of the smallest species to date to carry geolocators, decreased return rates but had no effect on inter-annual territory fidelity. Aims: To examine the effects of light-level geolocators on return rates and inter-annual territory fidelity of adult, male Prairie Warblers migrating to and from their non-breeding grounds. Methods: During the 2016 breeding season we captured adult male Prairie Warblers at two sites in northeastern USA and attached geolocators and colour rings to one group of...

Cellulose nanofibrils (CNFs) have already been proved to be a potential candidate as one of the next-generation renewable and sustainable packaging materials. However, the mechanical and barrier properties of CNF films are not yet up to the mark for certain applications, especially at higher relative humidity. Those properties can be controlled by the degree of fibrillation of fibers and drying methods of films. Here we prepared CNF films from CNF suspensions with two different degrees of fibrillation - standard CNF (90% fine) and high-fine CNF (97% fine) by casting and filtration. These...

This article describes a fast and reliable method of screening membrane materials designed by measuring moisture vapor transmission rate (WVTR) and permeance of membrane materials using a Payne-style diffusion cell (dry cup) placed in a Dynamic Vapor Sorption (DVS) instrument. The materials were cellulose nanocrystals (CNC)/polydimethylsiloxane (PDMS) hybrid membranes. A casting method was used to fabricate three types of membrane samples. The WVTR and permeance of the samples were measured at two RH (RH) levels of 60% and 80% at 25 C. The results revealed that the WVTR and permeance of...

Common woolly sunflower occurs from British Columbia south to California, east to Nevada, northwestern Utah, and western Wyoming and Montana (Johnson and Mooring 2006). Variety integrifolium is the most widely distributed of the common woolly sunflower varieties (Table 1). Varieties obovatum and hallii are uncommon (Mooring 2001). Variety hallii is known from only two populations in Kern and Santa Barbara counties, California (Tibor 2001 cited in Johnson and Mooring [2006]).

Resistance to fusiform rust disease in loblolly pine (Pinus taeda) is a classic gene-for-gene system. Early resistance gene mapping in the P. taeda family 10-5 identified RAPD markers for a major fusiform rust resistance gene, Fr1. More recently, single nucleotide polymorphism (SNP) markers associated with resistance were mapped to a full-length gene model in the loblolly pine genome encoding for a nucleotide-binding site leucine-rich repeat (NLR) protein. NLR genes are one of the most abundant gene families in plant genomes and are involved in effector-triggered immunity. Inter- and...

Remote Amazonian communities are often largely self-sufficient, made possible in part by their agricultural skills and deep ecological knowledge of their landscapes. Mastery of their local flora undoubtedly plays a vital role in daily life, yet communities in the Amazon can vary widely in both the diversity of plants that they utilize and in how they manage plants in their agricultural landholdings. The dominant drivers of these differences in ecological knowledge and practices between communities are not clearly understood. We compare the agricultural practices and diversity of utilized...

Quantifying tree canopy cover is fundamental to applications in forestry and ecology, but estimates vary substantially depending on type of field measurement, imagery, or active sensing used. Our objective was to improve estimates of stand-level canopy cover from standard tree inventory measurements, using representative data collected across diverse forest plant association groups across Oregon, USA. Canopy cover was measured with line intercept sampling on 1706 inventory plots and compared to calculations from individually tallied trees. We investigated adjustments of tree crown area...