Treesearch

An estimated 2 billion ha of forests are degraded globally and global change suggests even greater need for forest restoration. Four forest restoration paradigms are identified and discussed: revegetation, ecological restoration, functional restoration, and forest landscape restoration. Restoration is examined in terms of a degraded starting point and an ending point of an idealized natural forest. Global change, climate variability, biotechnology, and synthetic biology pose significant challenges to current restoration paradigms, underscoring the importance of clearly defined goals...

This field guide identifies seven primary components that largely determine resilience to disturbance, as well as resistance to invasive grasses and plant succession following treatment of areas of concern. The primary components are (1) characteristics of the ecological site, (2) current vegetation prior to treatment, (3) disturbance history, (4) type, timing, and severity of the treatment, (5) post-treatment weather, (6) post-treatment management, especially grazing, and (7) monitoring and adaptive management. A series of key questions and a set of tools are provided to assess these...

There is increasing interest worldwide in managing forests to maintain or improve biodiversity, enhance ecosystem services and assure long-term sustainability of forest resources. An important goal of forest management is to increase stand diversity, provide wildlife habitat and improve forest species diversity. We synthesize results from natural spruce forests in southeast Alaska and suggest strategies for managing Sitka spruce plantations in other parts of the world to benefit biodiversity and enhance a variety of forest ecosystem services. We also discuss the roles of fungi in increasing...

In the field of conversion of biomass to ethanol, an important area of research is the enzymatic hydrolysis of cellulose. Once cellulose is converted to glucose, it can be easily fermented to ethanol. As the cellulosic ethanol technology stands now, costly pretreatments and high dosages of cellulases are needed to achieve complete hydrolysis of the cellulose fraction of the biomass.1-3 This is mostly due to the inability of the enzymes to fully access the cellulose fraction given the complex plant cell wall structure. Many different technologies are being developed to modify the biomass to...

The fate of lignin from wheat straw, Miscanthus, and Loblolly pine after pretreatment by a non-toxic and recyclable ionic liquid (IL), [C2mim][OAc], followed by enzymatic hydrolysis was investigated. The lignin partitioned into six process streams, each of which was quantified and analyzed by a combination of a novel solution-state two-dimensional (2D) nuclear magnetic resonance (NMR) method, and size exclusion chromatography (SEC). Pretreatment of biomass samples by [C2mim][OAc] at 120 and 160 °C enhances hydrolysis rates and enzymatic glucan digestions compared to those of untreated...

This paper characterizes the corrosion rate of embedded fasteners as a function of wood moisture content using gravimetric and electrochemical measurements. The results indicated that the corrosion rate increased with moisture content before reaching a plateau. The phases present in the corrosion products, as analyzed using X-ray diffraction, are generally consistent with previous work. Uniform corrosion was observed for all fasteners and all conditions except steel fasteners embedded in water-saturated wood. Data of dependence of corrosion rate on moisture content, presented herein, are...

This handbook and financial app is a guide to help communities quickly determine if biomass energy projects might work for them so that this option is not overlooked. Its purpose is as a screening tool designed to save significant time, resources, and investment by weeding out those wood energy projects that may never come to fruition from those that have a chance of success. It establishes technical, financial, and social criteria and indicators to evaluate proposed biomass investment options. Through showcasing of successful projects using text, photos, video interviews, and diagrams, it...

We present information on the urban forests and land uses within the watershed of Puerto Rico’s 21 658-ha San Juan Bay Estuary based on urban forest inventories undertaken in 2001 and 2011. We found 2548 ha of mangrove and subtropical moist secondary forests covering 11.8 percent of the total watershed area in 2011. Red, black, and white mangroves (Rhizophora mangle, Avicennia germinans, and Laguncularia racemosa) were the most common species due to the watershed’s extensive mangrove forests, while tulipan africano (Spathodea campanulata) and María (Calophyllum antillanum) were predominant...

A study to determine the effects of environmental conditions on the growth of longleaf pine (Pinus palustris Mill.) was initiated in 1969 on the Escambia Experimental Forest near Brewton, Alabama, USA. This study sample consisted of forty young naturally regenerated, even aged longleaf pine seedlings evenly divided between two soil types. At the beginning of the study, the seedlings were 14 years from seed and ranged in height from 0.8 to 1.5 m. From 1969 to 1970, height and diameter measurements were recorded once to four times weekly during the growing seasons and once a month during the...

Responses to variation in light intensity, simulated herbivory by clipping, and their interaction were studied over three seasons in a factorial experimental design. Six major species of southeast Alaska forest understories were studied, each as a separate experiment: bunchberry, Cornus canadensis L.; threeleaf foamflower, Tiarella trifoliata L.; oval-leaf blueberry, Vaccinium ovalifolium Sm.; salmonberry, Rubus spectabilis Pursh; devilsclub, Oplopanax horridus (Sm.) Miq.; and western hemlock, Tsuga heterophylla (Raf.) Sarg. Seedlings of each species were grown in plastic grow pots under...