Treesearch

Forest health issues are on the rise in the United States, resulting from introduction of alien pests and diseases, coupled with abiotic stresses related to climate change. Increasingly, forest scientists are finding genetic/genomic resources valuable in addressing forest health issues. For a set of ten ecologically and economically important native hardwood tree species representing a broad phylogenetic spectrum, we used low coverage whole genome sequencing from multiplex Illumina paired ends to economically profile their genomic content. For six species, the genome content was further...

Many global change drivers chronically alter resource availability in terrestrial ecosystems. Such resource alterations are known to affect aboveground net primary production (ANPP) in the short term; however, it is unknown if patterns of response change through time. We examined the magnitude, direction, and pattern of ANPP responses to a wide range of global change drivers by compiling 73 datasets from long-term (>5 years) experiments that varied by ecosystem type, length of manipulation, and the type of manipulation. Chronic resource alterations resulted in a significant change in ANPP...

USDA conservation programs and practices seek to address societal resource concerns that arise from intensive agricultural production. These concerns include degradation of water quality and soils, and loss of valued ecological services provided by natural ecosystems

Among the wide array of terrestrial habitats, forest andwooded lands are the richest fromboth biological and genetic points of view because of their inherent structural and compositional complexity and diversity. Although species composition is an important biodiversity feature, forest structuremay be evenmore relevant for biodiversity assessments because a diversified structure is likely to have more niches, which in turn, host more species and contribute to a more efficient use of available resources. Structure plays a major role as a diversity indicator formanagement purposes where maps...

This chapter describes past interaction of human populations with habitats on mainland Yap and the dynamics of the agroecosystem that developed. Recent changes in this system on mainland Yap are described, followed by a description of the nature and threats to agriculture in the Outer Islands. The chapter concludes by asking “Where to now?” and considers a past agricultural intensification relevant to meeting future challenges.

The complex topography of the Inland Northwestern United States (58.4 million ha) interacts with soils and a highly variable climate to provide a mosaic of dry and moist mixed conifer forest settings. Approximately 20% of the area is covered by dry forests dominated by Pinus ponderosa, Pseudotsuga menziesii and contains a diversity of lower vegetation ranging from a grass savannah on the less-productive sites to shrub and forb dominated vegetation on the more-productive sites. An estimated 18% of the area is covered by moist mixed conifer forests with some places growing up to 10 different...

The US Environmental Protection Agency (USEPA) develops methods and tools for evaluating risk management strategies for sediments contaminated with polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and other legacy pollutants. Monitored natural recovery is a risk management alternative that relies on existing physical, chemical, and biological processes to contain, destroy, and/or reduce the bioavailability or toxicity of in-place contaminants. These naturally occurring processes are monitored to ensure that management and recovery are progressing as expected. One...

On a cool August morning, Chinook salmon (Oncorhynchus tshawytscha) fulfill an ancient ritual in the wilderness. Despite the rigors of an 850-mile journey, the female excavates a redd (nest) by moving stream gravels with her tail while males spar for a place beside her. In an ultimate act of nurturing, these salmon spawn and die, their bodies providing essential nutrients for the next generation of salmon and a host of other aquatic and terrestrial organisms. Northwest salmon have been performing this reproductive ritual for at least two million years, and in 2014 this place and these...

A new species, Phlebopus mexicanus, is described from southern tropical rainforests of Mexico based on morphological and molecular characters. Several features distinguish this species from others of Phlebopus including the medium to small basidiomata with olivaceous brown tomentose pileus that becomes finely areolate cracked with age, the dark yellow brown pruina covering most of the stipe, the pale yellow flesh of pileus and stipe that slowly turns blue when exposed, and the lack of hymenial cystidia. Phylogenetic analyses using nLSU sequences support the recognition of this new morpholog...