Treesearch

Nearly one-third of Earth’s total land area is covered by a remarkably complex and richly alive skin: forest soil. This layer – more membrane than crust – is of central importance to the survival of most organisms on our planet. Forest soils help provide an abundance of goods and services to humans including food, fuel, timber, medicines, water, oxygen, biodiversity, climate and hydrological regulation, not to mention a wealth of spiritual, cultural, and aesthetic benefts. For this, humanity is outright lucky but also profoundly challenged with the responsibility for stewarding this...

From the outset of this book project, we wanted to address three simple questions: how are forest soils faring in our rapidly changing world? Then, how are we progressing as stewards of global soils? Finally, how can we improve our stewardship to meet the challenges of a changing world? We challenged our subject experts to provide insights into the condition of Earth’s forest soils, their current management, future needs, and proposed actions where current practice falls short. From Asmeret Berhe (Chapter 3) comes the related concern that sustainable forest management needs to be rooted in...

Although mineral dissolution is a fundamental soil forming process, primary mineral content of soils is rarely inventoried or quantified. Concerns about maintenance of forest soil nutrient stocks require better mineralogic data. In particular, to understand recovery from Ca losses induced by acid deposition and sustainability of intensive forest harvest, better inventory of primary Ca minerals is needed. We developed a method based on electron probe micro-analysis to quantify primary mineral concentrations in soil. Samples analyzed from three sites in the glaciated northeastern United...

Longleaf pine (Pinus palustris Mill.) and shortleaf pine (Pinus echinata Mill.) are priority species targeted for increased restoration on the national forests in the Southern Region of the U.S. Department of Agriculture, Forest Service. The genetic integrity of both species is important to ensure adaptation, survival, and resilience of future forests. Longleaf x loblolly pine hybrids (Pinus x sondereggeri H.H. Chapm. ex Sudw. [palustris x taeda]) and shortleaf x loblolly pine hybrids are known to occur in the general forests, but at a rate of less than 5 percent. Climate change can...

Rising temperatures and changes in precipitation may affect plant responses, and mountainous regions in particular are sensitive to the impacts of climate change. The Santa Catalina Mountains, near Tucson, Arizona, USA, are among the best known Madrean Sky Islands, which are defined by pine-oak forests. We compared the sensitivity and temporal stability of climate–growth relationships to quantify the growth responses of sympatric taxa of ponderosa pine to changing climate. Three taxa (three-needle, mixed-needle, and five-needle types) collected from southern slopes of two contact zones...

While the importance of floral odours for pollinator attraction relative to visual cues is increasingly appreciated, how they structure community‐level plant–pollinator interactions is poorly understood. Elucidating the functional roles of flowering plant species with respect to their floral volatile organic compounds (VOCs) and how those roles vary over the growing season is an initial step towards understanding the contribution of floral VOCs to plant-pollinator interaction structure.

1. Interactions between distantly related herbivores exert powerful influences on ecosystems, but most studies to date have only considered unidirectional effects. Few have simultaneously examined the mutual effects that vertebrate herbivores and insect herbivores have on one another. 2. We conducted a set of manipulative experiments to evaluate the potential competition and facilitation between two pairs of distantly related herbivore taxa: an insect caterpillar (Gynaephora alpherakii) and two large vertebrate herbivores, yak (Bos grunniens) and Tibetan sheep (Ovis aries tibetica). 3. We...

More research on the effects of climate change has been dedicated to birds than to any other group of animals. It may, then, be surprising how few synthetic works exist that compile what we know so far. To be sure, excellent books are available on the subject— prominent examples include Birds and Climate Change: Impacts and Conservation Responses (Pearce-Higgins and Green 2014), Winged Sentinels: Birds and Climate Change (Wormworth and Sekercioglu 2011), and several works on specialized topics. The aforementioned books are syntheses by individual ornithologists; to my knowledge, the first...

Assessing forest degradation has been a challenging task due to the generally slow-changing nature of the process, which demands long periods of observation and high frequency of records. This research contributes to efforts aimed at detecting forest degradation by analyzing the trend component of the time series of Leaf Area Index (LAI) collected by the Moderate Resolution Imaging Spectroradiometer (MODIS) over Central Mexico from 2002 to 2017. The analysis of the trend component is proposed to overcome the challenge of identifying very subtle and gradual changes that can be undetected if...

Background: Mycoviruses were recently discovered in the white pine blister rust (WPBR) fungus Cronartium ribicola (J.C. Fisch.). Detection and characterization of their double stranded RNA (dsRNA) would facilitate understanding of pathogen virulence and disease pathogenesis in WPBR systems. Methods: Full-length cDNAs were cloned from the dsRNAs purified from viral-infected C. ribicola, and their cDNA sequences were determined by DNA sequencing. Evolutionary relationships of the dsRNAs with related mycoviruses were determined by phylogenetic analysis. Dynamic distributions of the viral RNAs...