WorldWideScience

Sample records for northern arizona forest

  1. Community occupancy responses of small mammals to restoration treatments in ponderosa pine forests, northern Arizona, USA.

    Science.gov (United States)

    Kalies, E L; Dickson, B G; Chambers, C L; Covington, W W

    2012-01-01

    In western North American conifer forests, wildfires are increasing in frequency and severity due to heavy fuel loads that have accumulated after a century of fire suppression. Forest restoration treatments (e.g., thinning and/or burning) are being designed and implemented at large spatial and temporal scales in an effort to reduce fire risk and restore forest structure and function. In ponderosa pine (Pinus ponderosa) forests, predominantly open forest structure and a frequent, low-severity fire regime constituted the evolutionary environment for wildlife that persisted for thousands of years. Small mammals are important in forest ecosystems as prey and in affecting primary production and decomposition. During 2006-2009, we trapped eight species of small mammals at 294 sites in northern Arizona and used occupancy modeling to determine community responses to thinning and habitat features. The most important covariates in predicting small mammal occupancy were understory vegetation cover, large snags, and treatment. Our analysis identified two generalist species found at relatively high occupancy rates across all sites, four open-forest species that responded positively to treatment, and two dense-forest species that responded negatively to treatment unless specific habitat features were retained. Our results indicate that all eight small mammal species can benefit from restoration treatments, particularly if aspects of their evolutionary environment (e.g., large trees, snags, woody debris) are restored. The occupancy modeling approach we used resulted in precise species-level estimates of occupancy in response to habitat attributes for a greater number of small mammal species than in other comparable studies. We recommend our approach for other studies faced with high variability and broad spatial and temporal scales in assessing impacts of treatments or habitat alteration on wildlife species. Moreover, since forest planning efforts are increasingly focusing on

  2. Late Holocene geomorphic record of fire in ponderosa pine and mixed-conifer forests, Kendrick Mountain, northern Arizona, USA

    Science.gov (United States)

    Sara E. Jenkins; Carolyn Hull Sieg; Diana E. Anderson; Darrell S. Kaufman; Philip A. Pearthree

    2011-01-01

    Long-term fire history reconstructions enhance our understanding of fire behaviour and associated geomorphic hazards in forested ecosystems. We used 14C ages on charcoal from fire-induced debris-flow deposits to date prehistoric fires on Kendrick Mountain, northern Arizona, USA. Fire-related debris-flow sedimentation dominates Holocene fan deposition in the study area...

  3. Carbon Stocks and Climate Change: Management Implications in Northern Arizona Ponderosa Pine Forests

    Directory of Open Access Journals (Sweden)

    Benjamin Bagdon

    2014-04-01

    Full Text Available Researchers have observed climate-driven shifts of forest types to higher elevations in the Southwestern US and predict further migration coupled with large-scale mortality events proportional to increases in radiative forcing. Range contractions of forests are likely to impact the total carbon stored within a stand. This study examines the dynamics of Pinus ponderosa stands under three climate change scenarios in Northern Arizona using the Climate Forest Vegetation Simulator (Climate-FVS model to project changes in carbon pools. A sample of 90 stands were grouped according to three elevational ranges; low- (1951 to 2194 m, mid- (2194 to 2499 m, and high- (2499 to 2682 m. elevation stands. Growth, mortality, and carbon stores were simulated in the Climate-FVS over a 100 year timespan. We further simulated three management scenarios for each elevational gradient and climate scenario. Management included (1 a no-management scenario, (2 an intensive-management scenario characterized by thinning from below to a residual basal area (BA of 18 m2/ha in conjunction with a prescribed burn every 10 years, and (3 a moderate-management scenario characterized by a thin-from-below treatment to a residual BA of 28 m2/ha coupled with a prescribed burn every 20 years. Results indicate that any increase in aridity due to climate change will produce substantial mortality throughout the elevational range of ponderosa pine stands, with lower elevation stands projected to experience the most devastating effects. Management was only effective for the intensive-management scenario; stands receiving this treatment schedule maintained moderately consistent levels of basal area and demonstrated a higher level of resilience to climate change relative to the two other management scenarios. The results of this study indicate that management can improve resiliency to climate change, however, resource managers may need to employ more intensive thinning treatments than

  4. Satellite Image-based Estimates of Snow Water Equivalence in Restored Ponderosa Pine Forests in Northern Arizona

    Science.gov (United States)

    Sankey, T.; Springer, A. E.; O'Donnell, F. C.; Donald, J.; McVay, J.; Masek Lopez, S.

    2014-12-01

    The U.S. Forest Service plans to conduct forest restoration treatments through the Four Forest Restoration Initiative (4FRI) on hundreds of thousands of acres of ponderosa pine forest in northern Arizona over the next 20 years with the goals of reducing wildfire hazard and improving forest health. The 4FRI's key objective is to thin and burn the forests to create within-stand openings that "promote snowpack accumulation and retention which benefit groundwater recharge and watershed processes at the fine (1 to 10 acres) scale". However, little is known about how these openings created by restoration treatments affect snow water equivalence (SWE) and soil moisture, which are key parts of the water balance that greatly influence water availability for healthy trees and for downstream water users in the Sonoran Desert. We have examined forest canopy cover by calculating a Normalized Difference Vegetation Index (NDVI), a key indicator of green vegetation cover, using Landsat satellite data. We have then compared NDVI between treatments at our study sites in northern Arizona and have found statistically significant differences in tree canopy cover between treatments. The control units have significantly greater forest canopy cover than the treated units. The thinned units also have significantly greater tree canopy cover than the thin-and-burn units. Winter season Landsat images have also been analyzed to calculate Normalized Difference Snow Index (NDSI), a key indicator of snow water equivalence and snow accumulation at the treated and untreated forests. The NDSI values from these dates are examined to determine if snow accumulation and snow water equivalence vary between treatments at our study sites. NDSI is significantly greater at the treated units than the control units. In particular, the thinned forest units have significantly greater snow cover than the control units. Our results indicate that forest restoration treatments result in increased snow pack

  5. Late Holocene geomorphic record of fire in ponderosa pine and mixed-conifer forests, Kendrick Mountain, northern Arizona, USA

    Science.gov (United States)

    Jenkins, S.E.; Hull, Sieg C.; Anderson, D.E.; Kaufman, D.S.; Pearthree, P.A.

    2011-01-01

    Long-term fire history reconstructions enhance our understanding of fire behaviour and associated geomorphic hazards in forested ecosystems. We used 14C ages on charcoal from fire-induced debris-flow deposits to date prehistoric fires on Kendrick Mountain, northern Arizona, USA. Fire-related debris-flow sedimentation dominates Holocene fan deposition in the study area. Radiocarbon ages indicate that stand-replacing fire has been an important phenomenon in late Holocene ponderosa pine (Pinus ponderosa) and ponderosa pine-mixed conifer forests on steep slopes. Fires have occurred on centennial scales during this period, although temporal hiatuses between recorded fires vary widely and appear to have decreased during the past 2000 years. Steep slopes and complex terrain may be responsible for localised crown fire behaviour through preheating by vertical fuel arrangement and accumulation of excessive fuels. Holocene wildfire-induced debris flow events occurred without a clear relationship to regional climatic shifts (decadal to millennial), suggesting that interannual moisture variability may determine fire year. Fire-debris flow sequences are recorded when (1) sufficient time has passed (centuries) to accumulate fuels; and (2) stored sediment is available to support debris flows. The frequency of reconstructed debris flows should be considered a minimum for severe events in the study area, as fuel production may outpace sediment storage. ?? IAWF 2011.

  6. Modeling snag dynamics in northern Arizona mixed-conifer and ponderosa pine forests

    Science.gov (United States)

    Joseph L. Ganey; Scott C. Vojta

    2007-01-01

    Snags (standing dead trees) are important components of forested habitats that contribute to ecological decay and recycling processes as well as providing habitat for many life forms. As such, snags are of special interest to land managers, but information on dynamics of snag populations is lacking. We modeled trends in snag populations in mixed-conifer and ponderosa...

  7. Rapid increase in log populations in drought-stressed mixed-conifer and ponderosa pine forests in northern Arizona

    Science.gov (United States)

    Joseph L. Ganey; Scott C. Vojta

    2012-01-01

    Down logs provide important ecosystem services in forests and affect surface fuel loads and fire behavior. Amounts and kinds of logs are influenced by factors such as forest type, disturbance regime, forest man-agement, and climate. To quantify potential short-term changes in log populations during a recent global- climate-change type drought, we sampled logs in mixed-...

  8. Fertilization in northern forests

    DEFF Research Database (Denmark)

    Hedwall, Per Ola; Gong, Peichen; Ingerslev, Morten

    2014-01-01

    resources into food, health and industrial products and energy. Fertilization in Sweden and Finland is currently practiced by extensive fertilization regimens where nitrogen fertilizers are applied once, or up to three times, during a rotation period, mainly in mature forest. This type of fertilization......Forests of northern ecosystems respond slowly to management activities and the possibilities to increase the growth in a short-term perspective and meet swift increases in society's demand for biomass are small. An exception among the silvicultural measures is fertilization which can be applied...... in combination with present management systems and, almost instantly, enhances forest productivity. There may, however, be both economic and environmental constraints to large-scale applications of fertilizers in forest. Here we review the literature concerning biomass production of forests under different...

  9. Vascular plant checklist of the Chimney Spring and Limestone Flats prescribed burning study areas within ponderosa pine experimental forests in northern Arizona (P-53)

    Science.gov (United States)

    Catherine Scudieri; James Fowler; Carolyn Hull Sieg; Laura Williams; Sally Haase

    2008-01-01

    This paper presents a vascular plant species list for two sites that are part of a long-term study exploring the effects of varying fire intervals on forest characteristics including the abundance and composition of understory vegetation. The Chimney Spring study area is on the Fort Valley Experimental Forest near Flagstaff, AZ and the Limestone Flats study area is on...

  10. Vascular plant checklist of the Chimney Spring and Limestone Flats Prescribed Burning Study Areas within ponderosa pine experimental forests in northern Arizona

    Science.gov (United States)

    Catherine Scudieri; James F. Fowler; Carolyn Hull Sieg; Laura Williams; Sally M. Haase

    2008-01-01

    This paper presents a vascular plant species list for two sites that are part of a long-term study exploring the effects of varying fire intervals on forest characteristics including the abundance and composition of understory vegetation. The Chimney Spring study area is on the Fort Valley Experimental Forest near Flagstaff, AZ, and the Limestone Flats study area is on...

  11. Public Land Survey (Township, Range, and Section) for northern Arizona, including Grand Canyon National Park.

    Data.gov (United States)

    National Park Service, Department of the Interior — This ALRIS (Arizona Land Resource Information System) coverage contains Public Land Survey gridding and labels for Townships, Ranges, and Sections for Northern Arizona

  12. Impacts of silvicultural thinning treatments on beetle trap captures and tree attacks during low bark beetle populations in ponderosa pine forests of northern Arizona.

    Science.gov (United States)

    Gaylord, M L; Hofstetter, R W; Wagner, M R

    2010-10-01

    Our research used a combination of passive traps, funnel traps with lures, baited trees, and surveys of long-term thinning plots to assess the impacts of different levels of stand basal area (BA) on bark beetle tree attack and on trap captures of Ips spp., Dendroctonus spp., and their predators. The study occurred at two sites in ponderosa pine, Pinus ponderosa Dougl. ex Laws., forests, from 2004 to 2007 during low bark beetle populations. Residual stand BA ranged from 9.0 to 37.0 m2/ha. More predators and bark beetles were collected in passive traps in stands of lower BA than in stands of higher BA; however, significance varied by species and site, and total number of beetles collected was low. Height of the clear panel passive traps affected trap catches for some species at some sites and years. When pheromone lures were used with funnel traps [Ips pini (Say) lure: lanierone, +03/-97 ipsdienol], we found no significant difference in trap catches among basal area treatments for bark beetles and their predators. Similarly, when trees were baited (Dendroctonus brevicomis LeConte lure: myrcene, exo-brevicomin and frontalin), we found no significant difference for days to first bark beetle attack. Surveys of long-term thinning treatments found evidence of bark beetle attacks only in unthinned plots (approximately 37 m2/ha basal area). We discuss our results in terms of management implications for bark beetle trapping and control.

  13. Fertilization in northern forests

    DEFF Research Database (Denmark)

    Hedwall, Per Ola; Gong, Peichen; Ingerslev, Morten

    2014-01-01

    resources into food, health and industrial products and energy. Fertilization in Sweden and Finland is currently practiced by extensive fertilization regimens where nitrogen fertilizers are applied once, or up to three times, during a rotation period, mainly in mature forest. This type of fertilization...

  14. 76 FR 22363 - Kaibab National Forest, Williams Ranger District; Arizona; Bill Williams Mountain Restoration...

    Science.gov (United States)

    2011-04-21

    ... Forest Service Kaibab National Forest, Williams Ranger District; Arizona; Bill Williams Mountain... forested conditions on and surrounding Bill Williams Mountain by reducing hazardous fuels and moving... approximately 4 miles south-southwest of the city of Williams, Arizona. The Proposed Action includes...

  15. 75 FR 48305 - Kaibab National Forest; Arizona; Uranium Exploratory Drilling Project

    Science.gov (United States)

    2010-08-10

    ... Forest Service Kaibab National Forest; Arizona; Uranium Exploratory Drilling Project AGENCY: Forest... an Environmental Impact Statement for the Uranium Exploratory Drilling Project, posted in the Federal...-delivered to Kaibab National Forest, Attn: VANE Minerals Uranium Exploratory Drilling Project, 800 S. 6th...

  16. The Flagstaff Festival of Science: Over 25 years of connecting research professionals with the people of Northern Arizona

    Science.gov (United States)

    Vaughan, R. G.; Ranney, W.; Stevens, B.; Farretta, K.

    2015-12-01

    The annual Flagstaff Festival of Science, established in 1990, is the longest running, entirely free, public science festival in the USA. It has evolved into a 10-day-long festival with >90 events, including interactive science and technology exhibits, daily public lectures, open houses, star parties, local field trips, and an in-school speaker program. The Festival events reach an estimated 17,000 people every year in Northern Arizona, including students from pre-K through college, parents, teachers, tourists, and lifelong learners. Flagstaff, AZ, "America's First STEM Community" and the "World's First International Dark Sky City," has a uniquely rich community of organizations engaged in science and engineering research and innovation, including the Flagstaff Arboretum, Flagstaff Dark Skies Coalition, Coconino Community College, W. L. Gore & Associates, Lowell Observatory, Museum of Northern Arizona, National Weather Service, National Park Service, National Forest Service, Northern Arizona University, Northern Arizona Center for Entrepreneurship and Technology, U.S. Geological Survey, U.S. Naval Observatory, and Willow Bend Environmental Education Center. As such, the Festival has tremendous support from the local community, which is evidenced by its financial support (via grants and donations), attendance, and awards it has received. Public STEM events are an increasingly popular way for scientists to reach underserved populations, and the Flagstaff Festival of Science provides local scientists and other research professionals with many diverse opportunities to foster public support of science and inspire students to study STEM disciplines. The goal of this presentation is to share information, ideas, and our experiences with anyone wishing to initiate or expand his or her current public STEM offerings; and to celebrate the rewards (for both learners and research professionals) of engaging in science education and communication at public STEM events.

  17. Geologic Map of Wupatki National Monument and Vicinity, Coconino County, Northern Arizona

    Science.gov (United States)

    Billingsley, George H.; Priest, Susan S.; Felger, Tracey J.

    2007-01-01

    Introduction The geologic map of Wupatki National Monument is a cooperative effort between the U.S. Geological Survey, the National Park Service, and the Navajo Nation to provide geologic information for resource management officials of the National Park Service, U.S. Forest Service, Navajo Indian Reservation (herein the Navajo Nation), and visitor information services at Wupatki National Monument, Arizona. Funding for the map was provided in part by the Water Rights Branch of the Water Resources Division of the National Park Service. Field work on the Navajo Nation was conducted under a permit from the Navajo Nation Minerals Department. Any persons wishing to conduct geologic investigations on the Navajo Nation must first apply for, and receive, a permit from the Navajo Nation Minerals Department, P.O. Box 1910, Window Rock, Arizona 86515, telephone (928)-871-6587. Wupatki National Monument lies within the USGS 1:24,000-scale Wupatki NE, Wupatki SE, Wupatki SW, Gray Mountain, East of SP Mountain, and Campbell Francis Wash quadrangles in northern Arizona. The map is bounded approximately by longitudes 111? 16' to 111? 32' 30' W. and latitudes 35? 30' to 35? 37' 40' N. The map area is in Coconino County on the southern part of the Colorado Plateaus geologic province (herein Colorado Plateau). The map area is locally subdivided into three physiographic parts, the Coconino Plateau, the Little Colorado River Valley, and the San Francisco Volcanic Field as defined by Billingsley and others (1997) [fig. 1]. Elevations range from 4,220 ft (1,286 m) at the Little Colorado River near the northeast corner of the map area to about 6,100 ft (1,859 m) at the southwest corner of the map area. The small community of Gray Mountain is about 16 mi (26 km) northwest of Wupatki National Monument Visitor Center, and Flagstaff, Arizona, the nearest metropolitan area, is about 24 mi (38 km) southwest of the Visitor Center (fig. 1). U.S. Highway 89 provides access to the west entrance of

  18. Forest carbon sinks in the Northern Hemisphere

    Science.gov (United States)

    Christine L. Goodale; Michael J. Apps; Richard A. Birdsey; Christopher B. Field; Linda S. Heath; Richard A. Houghton; Jennifer C. Jenkins; Gundolf H. Kohlmaier; Werner Kurz; Shirong Liu; Gert-Jan Nabuurs; Sten Nilsson; Anatoly Z. Shvidenko

    2002-01-01

    There is general agreement that terrestrial systems in the Northern Hemisphere provide a significant sink for atmospheric CO2; however, estimates of the magnitude and distribution of this sink vary greatly. National forest inventories provide strong, measurement-based constraints on the magnitude of net forest carbon uptake. We brought together...

  19. Geologic map of the Cameron 30' x 60' quadrangle, Coconino County, northern Arizona

    Science.gov (United States)

    Billingsley, George H.; Priest, Susan S.; Felger, Tracey J.

    2007-01-01

    This geologic map is the result of a cooperative effort of the U.S. Geological Survey and the National Park Service in collaboration with the Navajo Nation and the Hopi Tribe to provide regional geologic information for resource management officials of the National Park Service, U.S. Forest Service, Navajo Indian Reservation (herein the Navajo Nation), the Hopi Tribe, and for visitor information services at Grand Canyon National Park, Arizona as well as private enterprises that have lands within the area. The Cameron 30’ x 60’ quadrangle encompasses approximately 5,018 km2 (1,960 mi2) within Coconino County, northern Arizona and is bounded by longitude 111° to 112° W., and latitude 35°30’ to 36° N. The map area is within the southern Colorado Plateaus geologic province (herein Colorado Plateau). The map area is locally subdivided into six physiographic areas: the Grand Canyon (including the Little Colorado River Gorge), Coconino Plateau, Marble Plateau, Little Colorado River Valley, Moenkopi Plateau, and the San Francisco Volcanic Field as defined by Billingsley and others, 1997 (fig. 1). Elevations range from about 2,274 m (7,460 ft) at the south rim of Grand Canyon along State Highway 64 to about 994 m (3,260 ft) in the Grand Canyon, northeast quarter of the map area.The Cameron quadrangle is one of the few remaining areas near the Grand Canyon where uniform geologic mapping was needed for geologic connectivity of the regional geologic framework that will be useful to federal, state, and private land resource managers who direct environmental and land management programs such as range management, biological studies, flood control, and water resource investigations. The geologic information presented will support future and ongoing local geologic investigations and associated scientific studies of all disciplines within the Cameron quadrangle area.

  20. Water-quality assessment of the Central Arizona Basins, Arizona and northern Mexico; environmental setting and overview of water quality

    Science.gov (United States)

    Cordy, Gail E.; Rees, Julie A.; Edmonds, Robert J.; Gebler, Joseph B.; Wirt, Laurie; Gellenbeck, Dorinda J.; Anning, David W.

    1998-01-01

    The Central Arizona Basins study area in central and southern Arizona and northern Mexico is one of 60 study units that are part of the U.S. Geological Survey's National Water-Quality Assessment program. The purpose of this report is to describe the physical, chemical, and environmental characteristics that may affect water quality in the Central Arizona Basins study area and present an overview of water quality. Covering 34,700 square miles, the study area is characterized by generally north to northwestward-trending mountain ranges separated by broad, gently sloping alluvial valleys. Most of the perennial rivers and streams are in the northern part of the study area. Rivers and streams in the south are predominantly intermittent or ephemeral and flow in response to precipitation such as summer thunderstorms. Effluent-dependent streams do provide perennial flow in some reaches. The major aquifers in the study area are in the basin-fill deposits that may be as much as 12,000 feet thick. The 1990 population in the study area was about 3.45 million, and about 61 percent of the total was in Maricopa County (Phoenix and surrounding cities). Extensive population growth over the past decade has resulted in a twofold increase in urban land areas and increased municipal water use; however, agriculture remains the major water use. Seventy-three percent of all water with drawn in the study area during 1990 was used for agricultural purposes. The largest rivers in the study area-the Gila, Salt, and Verde-are perennial near their headwaters but become intermittent downstream because of impoundments and artificial diversions. As a result, the Central Arizona Basins study area is unique compared to less arid basins because the mean surface-water outflow is only 528 cubic feet per second from a total drainage area of 49,650 square miles. Peak flows in the northern part of the study area are the result of snowmelt runoff; whereas, summer thunderstorms account for the peak flows in

  1. Forest carbon sinks in the northern hemisphere

    NARCIS (Netherlands)

    Goodale, C.L.; Apps, M.J.; Birdsey, R.A.; Field, C.B.; Heath, L.S.; Houghton, R.A.; Jenkins, J.C.; Kohlmaier, G.H.; Kurz, W.; Liu, S.R.; Nabuurs, G.J.; Nilsson, S.; Shvidenko, A.Z.

    2002-01-01

    There is general agreement that terrestrial systems in the Northern Hemisphere provide a significant sink for atmospheric CO2; however, estimates of the magnitude and distribution of this sink vary greatly. National forest inventories provide strong, measuretment-based constraints on the magnitude o

  2. Geologic map of the eastern quarter of the Flagstaff 30’ x 60’ quadrangle, Coconino County, northern Arizona

    Science.gov (United States)

    Billingsley, George H.; Block, Debra; Hiza-Redsteer, Margaret

    2014-01-01

    The eastern quarter of the Flagstaff 30′ x 60′ quadrangle includes eight USGS 1:24,000-scale quadrangles in Coconino County, northern Arizona (fig. 1, map sheet): Anderson Canyon, Babbitt Wash, Canyon Diablo, Grand Falls, Grand Falls SE, Grand Falls SW, Grand Falls NE, and Meteor Crater. The map is bounded by lat 35° to 35°30′ N. and long 111° to 111°15′ W. and is on the southern part of the Colorado Plateaus geologic province (herein Colorado Plateau). Elevations range from 4,320 ft (1,317 m) at the Little Colorado River in the northwest corner of the map area to about 6,832 ft (2,082 m) at the southwest corner of the map. This geologic map provides an updated geologic framework for the eastern quarter of the Flagstaff 30′ x 60′ quadrangle and is adjacent to two other recent geologic maps, the Cameron and Winslow 30′ x 60′ quadrangles (Billingsley and others, 2007, 2013). This geologic map is the product of a cooperative effort between the U.S. Geological Survey (USGS) and the Navajo Nation. It provides geologic information for resource management officials of the U.S. Forest Service, the Arizona Game and Fish Department, and the Navajo Nation Reservation (herein the Navajo Nation). Funding for the map was provided by the USGS geologic mapping program, Reston, Virginia. Field work on the Navajo Nation was conducted under a permit from the Navajo Nation Minerals Department. Any persons wishing to conduct geologic investigations on the Navajo Nation must first apply for, and receive, a permit from the Navajo Nation Minerals Department, P.O. Box 1910, Window Rock, Arizona 86515, telephone (928) 871-6587.

  3. Geologic map of the northern White Hills, Mohave County, Arizona

    Science.gov (United States)

    Howard, Keith A.; Priest, Susan S.; Lundstrom, Scott C.; Block, Debra L.

    2017-07-10

    IntroductionThe northern White Hills map area lies within the Kingman Uplift, a regional structural high in which Tertiary rocks lie directly on Proterozoic rocks as a result of Cretaceous orogenic uplift and erosional stripping of Paleozoic and Mesozoic strata. The Miocene Salt Spring Fault forms the major structural boundary in the map area. This low-angle normal fault separates a footwall (lower plate) of Proterozoic gneisses on the east and south from a hanging wall (upper plate) of faulted middle Miocene volcanic and sedimentary rocks and their Proterozoic substrate. The fault is part of the South Virgin–White Hills Detachment Fault, which records significant tectonic extension that decreases from north to south. Along most of its trace, the Salt Spring Fault dips gently westward, but it also has north-dipping segments along salients. A dissected, domelike landscape on the eroded footwall, which contains antiformal salients and synformal reentrants, extends through the map area from Salt Spring Bay southward to the Golden Rule Peak area. The “Lost Basin Range” represents an upthrown block of the footwall, raised on the steeper Lost Basin Range Fault.The Salt Spring Fault, as well as the normal faults that segment its hanging wall, deform rocks that are about 16 to 10 Ma, and younger deposits overlie the faults. Rhyodacitic welded tuff about 15 Ma underlies a succession of geochemically intermediate to progressively more mafic lavas (including alkali basalt) that range from about 14.7 to 8 Ma, interfingered with sedimentary rocks and breccias in the western part of the map area. Upper Miocene strata record further filling of the extension-formed continental basins. Basins that are still present in the modern landscape reflect the youngest stages of extensional-basin formation, expressed as the downfaulted Detrital Valley and Hualapai Wash basins in the western and eastern parts of the map area, respectively, as well as the north-centrally located

  4. The impact of forest thinning on the reliability of water supply in central Arizona.

    Directory of Open Access Journals (Sweden)

    Silvio Simonit

    Full Text Available Economic growth in Central Arizona, as in other semiarid systems characterized by low and variable rainfall, has historically depended on the effectiveness of strategies to manage water supply risks. Traditionally, the management of supply risks includes three elements: hard infrastructures, landscape management within the watershed, and a supporting set of institutions of which water markets are frequently the most important. In this paper we model the interactions between these elements. A forest restoration initiative in Central Arizona (the Four Forest Restoration Initiative, or 4FRI will result in thinning of ponderosa pine forests in the upper watershed, with potential implications for both sedimentation rates and water delivery to reservoirs. Specifically, we model the net effect of ponderosa pine forest thinning across the Salt and Verde River watersheds on the reliability and cost of water supply to the Phoenix metropolitan area. We conclude that the sediment impacts of forest thinning (up to 50% of canopy cover are unlikely to compromise the reliability of the reservoir system while thinning has the potential to increase annual water supply by 8%. This represents an estimated net present value of surface water storage of $104 million, considering both water consumption and hydropower generation.

  5. Population status and population genetics of northern leopard frogs in Arizona

    Science.gov (United States)

    Theimer, Tad C.; Drost, Charles A.; O'Donnell, Ryan P.; Mock, Karen E.

    2011-01-01

    Increasing isolation of populations by habitat fragmentation threatens the persistence of many species, both from stochastic loss of small isolated populations, and from inbreeding effects in populations that have become genetically isolated. In the southwestern United States, amphibian habitat is naturally patchy in occurrence because of the prevailing aridity of the region. Streams, rivers, and other wetlands are important both as habitat and as corridors that connect populations. However, populations of some species have become more fragmented and isolated by habitat degradation and loss. Northern leopard frogs (Rana pipiens) have experienced serious declines in the Southwest. We conducted an extensive survey across the known range of northern leopard frogs in Arizona to determine the current distribution and abundance of the species. From a range that once spanned much of the northern and central part of the State, northern leopard frogs have been reduced to three or four widely separated populations, near Lyman Lake in east-central Arizona, in the Stoneman Lake area south of Flagstaff, along Truxton Wash near Peach Springs, and a population of uncertain extent on Navajo Nation lands. The Lyman Lake and Truxton Wash populations are small and extremely isolated. The Stoneman Lake population, however, is an extensive metapopulation spread across several stream drainages, including numerous ponds, wetlands, and artificial tanks. This is the only population in Arizona that is increasing in extent and numbers, but there is concern about the apparent introduction of nonnative genetic stock from eastern North America into this area. We analyzed genetic diversity within and genetic divergence among populations of northern leopard frogs, across both extant and recently extirpated populations in Arizona. We also analyzed mitochondrial DNA to place these populations into a larger phylogenetic framework and to determine whether any populations contained genetic material

  6. Growth, condition, diet, and consumption rates of northern pike in three Arizona reservoirs

    Science.gov (United States)

    Flinders, J.M.; Bonar, Scott A.

    2008-01-01

    Northern pike (Esox lucius L.) introductions are controversial in the western United States due to suspected impacts they might have on established sport fisheries and potential illegal introductions. Tbree Arizona reservoirs, Parker Canyon Lake, Upper Lake Mary and Long Lake were sampled to examine the diet, consumption dynamics, and growth of northern pike. Northern pike diets varied by season and reservoir. In Parker Canyon Lake, diets were dominated by rainbow trout in winter and spring and bluegill and green sunfish in the fall. In Long Lake the northern pike ate crayfish in spring and early summer and switched to young of the year common carp in summer and fall. Black crappie, golden shiners, and crayfish were the major prey in Upper Lake Mary during spring, but they switched to stocked rainbow trout in the fall. Northern pike growth was in the high range of growth reported throughout the United States. Estimated northern pike specific consumption rate (scr) of rainbow trout (g/g/d ?? 10-6) was greatest in Upper Lake Mary (scr = 329.1 ?? 23.7 g/g/d ?? 10-6) where stocked fingerling (280 mm TL) rainbow trout stocked in Long Lake (scr = 1.4 ?? 0.1 g/g/d ?? 10-6) and Parker Canyon Lake (scr = 287.2 ?? 15.1 g/g/d ?? 10-6) where catchable-sized rainbow trout were stocked. Managers should consider the cost-benefits of stocking fish >200 mm TL in lakes containing northern pike. ?? Copyright by the North American Lake Management Society 2008.

  7. VT Green Mountain National Forest Map - Northern Section

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The BasemapOther_GMNFMAPN is a cartographic map product depicting the northern half of the Green Mountain National Forest (GMNF). The paper map...

  8. 76 FR 51936 - Coconino and Kaibab National Forests, Arizona, Four-Forest Restoration Initiative

    Science.gov (United States)

    2011-08-19

    ... forests had widely-spaced large trees with a more open, herbaceous forest floor (Cooper 1960). These... disturbances and are vulnerable to large-scale disturbances such as changing climatic conditions...

  9. 76 FR 50168 - Coconino and Kaibab National Forests, Arizona, Four-Forest Restoration Initiative

    Science.gov (United States)

    2011-08-12

    ... century ago the pine forests had widely-spaced large trees with a more open, herbaceous forest floor... climatic conditions (drought), fire, insect, and disease. Purpose and Need for Action In contrast to...

  10. Ecological studies on rain forest in Northern Suriname

    NARCIS (Netherlands)

    Schulz, J.P.

    1960-01-01

    During the years 1955-1957 ecological data were collected in various types of mesophytic forest occurring in the northern half of central Suriname (fig. 1). Physiognomically as well as floristically these forests correspond with the type of vegetation which in the other parts of tropical America

  11. Ecological studies on rain forest in Northern Suriname

    NARCIS (Netherlands)

    Schulz, J.P.

    1960-01-01

    During the years 1955-1957 ecological data were collected in various types of mesophytic forest occurring in the northern half of central Suriname (fig. 1). Physiognomically as well as floristically these forests correspond with the type of vegetation which in the other parts of tropical America gen

  12. Ecology of beech forests in the northern hemisphere.

    NARCIS (Netherlands)

    Peters, R.

    1992-01-01

    Beech forests are dominated or codominated by at least one Fagus species. The beeches are a homogeneous group of 11 deciduous tree species growing in the Northern Hemisphere (Figure 1.1). They often dominate forest ecosystems throughout their ranges. The optimum for beech is on acidic and mesic loam

  13. Ecological studies on rain forest in Northern Suriname

    NARCIS (Netherlands)

    Schulz, J.P.

    1960-01-01

    During the years 1955-1957 ecological data were collected in various types of mesophytic forest occurring in the northern half of central Suriname (fig. 1). Physiognomically as well as floristically these forests correspond with the type of vegetation which in the other parts of tropical America gen

  14. Management impacts on forest floor and soil organic carbon in northern temperate forests of the US

    Science.gov (United States)

    Coeli M. Hoover

    2011-01-01

    The role of forests in the global carbon cycle has been the subject of a great deal of research recently, but the impact of management practices on forest soil dynamics at the stand level has received less attention. This study used six forest management experimental sites in five northern states of the US to investigate the effects of silvicultural treatments (light...

  15. Assessment of selected inorganic constituents in streams in the Central Arizona Basins Study Area, Arizona and northern Mexico, through 1998

    Science.gov (United States)

    Anning, David W.

    2003-01-01

    Stream properties and water-chemistry constituent concentrations from data collected by the National Water-Quality Assessment and other U.S. Geological Survey water-quality programs were analyzed to (1) assess water quality, (2) determine natural and human factors affecting water quality, and (3) compute stream loads for the surface-water resources in the Central Arizona Basins study area. Stream temperature, pH, dissolved-oxygen concentration and percent saturation, and dissolved-solids, suspended-sediment, and nutrient concentration data collected at 41 stream-water quality monitoring stations through water year 1998 were used in this assessment. Water-quality standards applicable to the stream properties and water-chemistry constituent concentration data for the stations investigated in this study generally were met, although there were some exceedences. In a few samples from the White River, the Black River, and the Salt River below Stewart Mountain Dam, the pH in reaches designated as a domestic drinking water source was higher than the State of Arizona standard. More than half of the samples from the Salt River below Stewart Mountain Dam and almost all of the samples from the stations on the Central Arizona Project Canal?two of the three most important surface-water sources used for drinking water in the Central Arizona Basins study area?exceeded the U.S. Environmental Protection Agency drinking water Secondary Maximum Contaminant Level for dissolved solids. Two reach-specific standards for nutrients established by the State of Arizona were exceeded many times: (1) the annual mean concentration of total phosphorus was exceeded during several years at stations on the main stems of the Salt and Verde Rivers, and (2) the annual mean concentration of total nitrogen was exceeded during several years at the Salt River near Roosevelt and at the Salt River below Stewart Mountain Dam. Stream properties and water-chemistry constituent concentrations were related to

  16. Paludification and forest retreat in northern oceanic environments.

    Science.gov (United States)

    Crawford, R M M; Jeffree, C E; Rees, W G

    2003-01-01

    Examination of temperature variations over the past century for Europe and the Arctic from northern Norway to Siberia suggests that variations in the North Atlantic Oscillation are associated with an increase in oceanicity in certain maritime regions. A southward depression of the tree line in favour of wet heaths, bogs and wetland tundra communities is also observed in northern oceanic environments. The physiological basis for this change in ecological succession from forest to bog is discussed in relation to the long-term effects of flooding on tree survival. The heightened values currently detected in the North Atlantic Oscillation Index, together with rising winter temperatures, and increased rainfall in many areas in northern Europe, presents an increasing risk of paludification with adverse consequences for forest regeneration, particularly in areas with oceanic climates. Climatic warming in oceanic areas may increase the area covered by bogs and, contrary to general expectations, lead to a retreat rather than an advance in the northern limit of the boreal forest. High water-table levels are not automatically detrimental to forest survival as can be seen in swamp, bottom land and mangrove forests. Consequently, the inhibitory effects of flooding on tree survival and regeneration in northern regions should not be uncritically accepted as merely due to high water levels. Evidence is discussed which suggests that physiological and ecological factors may interact to inhibit forest regeneration in habitats where there is a risk of prolonged winter-flooding combined with warmer winters and cool moist summers.

  17. Northern Forest DroughtNet: A New Framework to Understand Impacts of Precipitation Change on the Northern Forest Ecosystem

    Science.gov (United States)

    Asbjornsen, H.; Rustad, L.; Templer, P. H.; Jennings, K.; Phillips, R.; Smith, M.

    2014-12-01

    Recent trends and projections for future change for the U.S. northern forests suggest that the region's climate is becoming warmer, wetter, and, ironically, drier, with more precipitation occurring as large events, separated by longer periods with no precipitation. However, to date, precipitation manipulation experiments conducted in forest ecosystems represent only ~5% of all such experiments worldwide, and our understanding of how the mesic-adapted northern forest will respond to greater frequency and intensity of drought in the future is especially poor. Several important challenges have hampered previous research efforts to conduct forest drought experiments and draw robust conclusions, including difficulties in reducing water uptake by deep and lateral tree roots, logistical and financial constraints to establishing and maintaining large-scale field experiments, and the lack of standardized approaches for determining the appropriate precipitation manipulation treatment (e.g., amount and timing of throughfall displacement), designing and constructing the throughfall displacement infrastructure, identifying key response variables, and collecting and analyzing the field data. The overarching goal of this project is to establish a regional research coordination network - Northern Forest DroughtNet - to investigate the impacts of changes in the amount and distribution of precipitation on the hydrology, biogeochemistry, and carbon (C) cycling dynamics of northern temperate forests. Specific objectives include the development of a standard prototype for conducting precipitation manipulation studies in forest ecosystems (in collaboration with the international DroughtNet-RCN) and the implementation of this prototype drought experiment at the Hubbard Brook Experimental Forest. Here, we present the advances made thus far towards achieving the objectives of Northern Forest DroughtNet, plans for future work, and an invitation to the larger scientific community interested

  18. Northern Forest Ecosystem Dynamics Using Coupled Models and Remote Sensing

    Science.gov (United States)

    Ranson, K. J.; Sun, G.; Knox, R. G.; Levine, E. R.; Weishampel, J. F.; Fifer, S. T.

    1999-01-01

    Forest ecosystem dynamics modeling, remote sensing data analysis, and a geographical information system (GIS) were used together to determine the possible growth and development of a northern forest in Maine, USA. Field measurements and airborne synthetic aperture radar (SAR) data were used to produce maps of forest cover type and above ground biomass. These forest attribute maps, along with a conventional soils map, were used to identify the initial conditions for forest ecosystem model simulations. Using this information along with ecosystem model results enabled the development of predictive maps of forest development. The results obtained were consistent with observed forest conditions and expected successional trajectories. The study demonstrated that ecosystem models might be used in a spatial context when parameterized and used with georeferenced data sets.

  19. Explaining reported puma-related behaviors and behavioral intentions among northern Arizona residents

    Science.gov (United States)

    Mattson, David J.; Ruther, Elizabeth J.

    2012-01-01

    Management of pumas in the American West is typified by conflict among stakeholders plausibly rooted in life experiences and worldviews. We used a mail questionnaire to assess demographics, nature-views, puma-related life experiences and behaviors, and support for puma-related policies among residents of northern Arizona. Data from the questionnaire (n = 693 respondents) were used to model behaviors and support for policies. Compared to models based on nature-views and life experiences, those based on demographics had virtually no support from the data. The Utilitarian/Dominionistic nature-view had the strongest effect of any variable in six of seven models, and was associated with firearms and opposition to policies that would limit killing pumas. The Humanistic/Moralistic nature-view was positively associated with non-lethal behaviors and policies in five models. Gender had the strongest effect of any demographic variable. Compared to demographics alone, our results suggest that worldviews provide a more meaningful explanation of reported human behaviors and behavioral intentions regarding pumas.

  20. Rock formations in the Colorado Plateau of Southeastern Utah and Northern Arizona

    Science.gov (United States)

    Longwell, C.R.; Miser, H.D.; Moore, R.C.; Bryan, Kirk; Paige, Sidney

    1925-01-01

    The field work of which this report is a record was done in the summer and fall of 1921 by members of the United States Geological Survey. A project to build a large storage dam at Lees Ferry, on Colorado River in northern Arizona, called for a detailed topographic survey of the area covered by the project, for the purpose of determining the capacity of the reservoir. This work was undertaken by the United States Geological Survey in cooperation with the Southern California Edison Co. Three surveying parties were sent to the field, each accompanied by a geologist, whose specific duty was to study and report on the rock formations within the area to be flooded. One topographic party, under A. T. Fowler, which started at Lees Ferry and worked up stream in Arizona, was accompanied by Kirk Bryan. Another party, under K. W. Trimble, which started near Bluff and worked down the San Juan and thence down the Colorado, was accompanied by H. D. Miser. The third party, under W. R. Chenoweth, worked from Fremont River to the Waterpocket Fold and then returned to Green River, Utah, and traversed Cataract Canyon during the period of low water. C. R. Longwell was with this party until September, when his place was taken by Sidney Paige. Mr. Paige, in company with the Kolb brothers, E. C. La Rue, and Henry Ranch, left the Chenoweth party after Cataract Canyon had been surveyed and rowed down the Colorado to the mouth of the San Juan, where they were joined by Mr. Miser. Then they took a hurried trip by boat down the Colorado to Lees Ferry, making a few short stops and visiting the famous Rainbow Bridge. Thus the geology of the canyons of Colorado and San Juan rivers and of the lower parts of tributary canyons was examined continuously, and reconnaissance work was done in the country back from the rivers. At the same time a fourth party, under R. C. Moore, was mapping parts of Kane, Garfield, and Wayne counties, Utah, to determine whether oil might be found there. The present paper

  1. Phenological Response of an Arizona Dryland Forest to Short-Term Climatic Extremes

    Directory of Open Access Journals (Sweden)

    Jessica Walker

    2015-08-01

    Full Text Available Baseline information about dryland forest phenology is necessary to accurately anticipate future ecosystem shifts. The overarching goal of our study was to investigate the variability of vegetation phenology across a dryland forest landscape in response to climate alterations. We analyzed the influence of site characteristics and climatic conditions on the phenological patterns of an Arizona, USA, ponderosa pine (Pinus ponderosa forest during a five-year period (2005 to 2009 that encompassed extreme wet and dry precipitation regimes. We assembled 80 synthetic Landsat images by applying the spatial and temporal adaptive reflectance fusion method (STARFM to 500 m MODIS and 30 m Landsat-5 Thematic Mapper (TM data. We tested relationships between site characteristics and the timing of peak Normalized Difference Vegetation Index (NDVI to assess the effect of climatic stress on the green-up of individual pixels during or after the summer monsoon. Our results show that drought-induced stress led to a fragmented phenological response that was highly dependent on microsite parameters, as both the spatial autocorrelation of peak timing and the number of significant site variables increased during the drought year. Pixels at lower elevations and with higher proportions of herbaceous vegetation were more likely to exhibit dynamic responses to changes in precipitation conditions. Our study demonstrates the complexity of responses within dryland forest ecosystems and highlights the need for standardized monitoring of phenology trends in these areas. The spatial and temporal variability of phenological signals may provide a quantitative solution to the problem of how to evaluate dryland land surface trends across time.

  2. 75 FR 11554 - Notice of Intent to Repatriate Cultural Items: Museum of Northern Arizona, Flagstaff, AZ

    Science.gov (United States)

    2010-03-11

    ... Native American religious leaders for the practice of traditional Native American religions by their... between the sacred objects/objects of cultural patrimony and the Navajo Nation, Arizona, New Mexico & Utah.... Repatriation of the sacred objects/objects of cultural patrimony to the Navajo Nation, Arizona, New...

  3. Paludification and Forest Retreat in Northern Oceanic Environments

    OpenAIRE

    2003-01-01

    Examination of temperature variations over the past century for Europe and the Arctic from northern Norway to Siberia suggests that variations in the North Atlantic Oscillation are associated with an increase in oceanicity in certain maritime regions. A southward depression of the treeline in favour of wet heaths, bogs and wetland tundra communities is also observed in northern oceanic environments. The physiological basis for this change in ecological succession from forest to bog is discuss...

  4. Geology of the Northern Part of the Harcuvar Complex, West-Central Arizona

    Science.gov (United States)

    Bryant, Bruce; Wooden, J.L.

    2008-01-01

    In west-central Arizona near the northeast margin of the Basin and Range Province, the Rawhide detachment fault separates Tertiary and older rocks lacking significant effects of Tertiary metamorphism from Precambrian, Paleozoic, and Mesozoic rocks in the Harcuvar metamorphic core complex below. Much of the northern part of the Harcuvar complex in the Buckskin and eastern Harcuvar Mountains is layered granitic gneiss, biotite gneiss, amphibolite, and minor pelitic schist that was probably deformed and metamorphosed in Early Proterozoic time. In the eastern Buckskin Mountains, Early and Middle Proterozoic plutons having U-Pb zircon ages of 1,683?6.4 mega-annum (Ma) and 1,388?2.3 Ma, respectively, intruded the layered gneiss. Small plutons of alkaline gabbro and diorite intruded in Late Jurassic time. A sample of mylonitized diorite from this unit has a U-Pb zircon age of 149?2.8 Ma. In the Early Cretaceous, amphibolite facies regional metamorphism was accompanied by partial melting and formation of migmatite. Zircon from a granitic layer in migmatitic gneiss in the eastern Harcuvar Mountains has a U-Pb age of 110?3.7 Ma. In the Late Cretaceous, sills and plutons of the granite of Tank Pass were emplaced in both the Buckskin and eastern Harcuvar Mountains. In the Buckskin Mountains those intrusions are locally numerous enough to form an injection migmatite. A pluton of this granite crops out over almost half the area of the eastern Harcuvar Mountains. Paleozoic and Mesozoic sedimentary rocks were caught as slices along south-vergent Cretaceous thrusts related to the Maria fold and thrust belt and were metamorphosed beneath a thick sheet of Proterozoic crustal rocks. Inception of volcanism and basin formation in upper-plate rocks indicates that regional extension started at about 26 Ma, in late Oligocene. The Swansea Plutonic Suite, composed of rocks ranging from gabbro to granite, intruded the lower-plate rocks in the Miocene and Oligocene(?). Granite and a gabbro

  5. Responses of northern forest plants to atmospheric changes

    Energy Technology Data Exchange (ETDEWEB)

    Laine, K.; Huttunen, S.; Kauppi, M.; Ohtonen, R.; Laehdesmaeki, P. [Oulu Univ. (Finland). Dept. of Biology

    1996-12-31

    This research programme has been under way since 1990 to study the long-term synergistic effects of air pollutants and changing climatic conditions on the northern forest ecosystem and to increase the knowledge of climatic change and its consequences for the fragile northern nature. Ecological, physiological, morphological and biochemical methods have been used to study the responses of forest trees, dwarf shrubs, lichens and soil biology to environmental changes. The research programme is divided into four subprojects concentrating on different ecosystem levels. The subprojects are: (1) life, growth and survival strategies of northern dwarf shrubs under the pressure of a changing environment, (2) forest trees under the impact of air pollutants, increasing CO{sub 2} and UV-B, (3) susceptibility of lichens to air pollution and climatic change and (4) impact of elevated atmospheric CO{sub 2} and O{sub 3} on soil biology with special reference to carbon allocation and N fixation in symbiotic systems. This report summarizes the results of short-term experiments which showed many ecological and physiological changes in almost all elements of the northern boreal forests. These species-level measurements focused on the key species of the northern boreal forest, which have been thought to be useful in large-scale ecosystem experiments and modelling. The results will also facilitate the further studies on the patterns of plant species distribution and northern ecosystem function with respect to the environmental parameters that are expected to change along with global change (e.g. temperature, airchemistry, UV-B, snow condition)

  6. Culturally and economically important nontimber forest products of northern Maine

    Science.gov (United States)

    Michelle J. Baumflek; Marla R. Emery; Clare. Ginger

    2010-01-01

    Nontimber forest products (NTFPs) gathered for food, medicine, craft, spiritual, aesthetic, and utilitarian purposes make substantial contributions to the economic viability and cultural vitality of communities. In the St. John River watershed of northern Maine, people identifying with cultural groups including Acadian, Maliseet, Mi'kmaq, Scotch-Irish, and Swedish...

  7. Investigation of the geology and hydrology of the Coconino Plateau of northern Arizona: a project of the Arizona Rural Watershed Initiative

    Science.gov (United States)

    Flynn, Marilyn E.; Bills, Donald J.

    2002-01-01

    The water resources of the Coconino Plateau in northern Arizona are under increasing demand as a result of development. The population of this arid region continues to grow, and the number of visitors to the many national and state parks and monuments in the region has increased annually. The sustainability, protection, and maintenance of springs and seeps and associated riparian habitat on the Coconino Plateau are major issues that have broad public and governmental support. Regional stakeholders agree that an improved understanding of the regional hydrogeologic system is needed to address the concerns of water supply and ground-water sustainability. The base of information required to adequately describe the hydrogeology of the Coconino Plateau currently does not exist. Hydrogeologic data is most abundant for large population centers like Flagstaff and Sedona, but is sparse for less populated areas like Williams, Tusayan, Valle, and Cameron. There are still large parts of the Coconino Plateau for which there is no basic geologic or hydrologic information available. In order to develop a hydrogeologic framework for the Coconino Plateau, a comprehensive effort is needs to compile existent data and collect additional data to fill in data gaps and reinforce limited information. In 1999, the U.S. Geological Survey (USGS) began an assessment of the hydrogeology of the Coconino Plateau in cooperation with the Arizona Department of Water Resources (ADWR) as part of the Rural Watershed Initiative, a program established by the State of Arizona and managed by the ADWR. Assessments also are underway in the upper-middle Verde River watershed (Woodhouse and others, 2002) to the south and in the Mogollon Highlands to the southeast (Parker and Flynn, 2000). Each study has as its objectives: (1) the collection, compilation, and evaluation of all existing geologic, hydrologic, and related data pertaining to the study area and the creation of a database that is readily accessible

  8. Effects of reintroduced beaver (Castor canadensis) on riparian bird community structure along the upper San Pedro River, southeastern Arizona and northern Sonora, Mexico

    Science.gov (United States)

    Johnson, Glenn E.; van Riper, Charles

    2014-01-01

    Chapter 1.—We measured bird abundance and richness along the upper San Pedro River in 2005 and 2006, in order to document how beavers (Castor canadensis) may act as ecosystem engineers after their reintroduction to a desert riparian area in the Southwestern United States. In areas where beavers colonized, we found higher bird abundance and richness of bird groups, such as all breeding birds, insectivorous birds, and riparian specialists, and higher relative abundance of many individual species—including several avian species of conservation concern. Chapter 2.—We conducted bird surveys in riparian areas along the upper San Pedro River in southeastern Arizona (United States) and northern Sonora (Mexico) in order to describe factors influencing bird community dynamics and the distribution and abundance of species, particularly those of conservation concern. These surveys were also used to document the effects of the ecosystem-altering activities of a recently reintroduced beavers (Castor canadensis). Chapter 3.—We reviewed Southwestern Willow Flycatcher (Empidonax traillii extimus) nest records and investigated the potential for future breeding along the upper San Pedro River in southeastern Arizona, where in July 2005 we encountered the southernmost verifiable nest attempt for the species. Continued conservation and management of the area’s riparian vegetation and surface water has potential to contribute additional breeding sites for this endangered Willow Flycatcher subspecies. Given the nest record along the upper San Pedro River and the presence of high-density breeding sites to the north, the native cottonwood-willow forests of the upper San Pedro River could become increasingly important to E. t. extimus recovery, especially considering the anticipated effect of the tamarisk leaf beetle (Diorhabda carinulata) on riparian habitat north of the region.

  9. Sustainable Development in Northern Africa: The Argan Forest Case

    Directory of Open Access Journals (Sweden)

    Dom Guillaume

    2009-11-01

    Full Text Available The argan tree is a slow growing tree exclusively endemic in the dry lowlands of Southwest Morocco. The argan forest constitutes a long time ignored specific biotope that has been declared a Biosphere Reserve by UNESCO in 1998. The argan forest is particularly fragile to climate change. Forecasts show annual precipitation levels and prolonged drought periods that could severely threaten the future of the argan forest. In some places, the argan forest is already damaged, resulting in the retreat of the argan tree and the subsequent desert encroachment. An acceleration of this trend would have devastating consequences. In response, some twenty years ago, an ambitious, unique in Northern-Africa, and government-supported program was initiated in Morocco to rescue the argan tree via the sustainable development of the argan forest. Because in the late 1980s, sustainable development in developing countries was often considered as a utopia, the argan forest case represents a sign of progress, as it is also an interesting and unique experience in Africa. This review analyses the process followed, the measures taken, the pitfalls encountered, and the results obtained during the last two decades. It also points out the measures that still need to be taken before declaring the argan forest rescue mission is accomplished.

  10. Ecological and biogeographical analyses of Mediterranean forests of northern Morocco

    Science.gov (United States)

    Ajbilou, Redouan; Marañón, Teodoro; Arroyo, Juan

    2006-01-01

    Mediterranean forests in northern Morocco have been studied. Tree species composition and abundance were investigated in 84 forest sites, distributed throughout the sandstone formation of the Tangier region. The relative abundance of 15 tree and arborescent shrub species was related, by ordination analysis, to altitude, disturbance by fire, and soil fertility. High-elevation forests were dominated by Cedrus atlantica, Quercus pyrenaica and Pinus pinaster. Sacred forests (protected as holy burial places) had a distinct stand structure, and were considered as refuges, for maintaining biodiversity at landscape scale. The evergreen oak Quercus suber and the semideciduous Quercus canariensis co-dominated the lowland forests. The mean basal area of the studied forests was 34 m 2 ha -1. The mean trunk size (dbh) for Q. suber was 24 cm and for Q. canariensis 36.5 cm; in both cases there were indications of declining regeneration at population level. A comparative biogeographical analysis with the equivalent region in southern Spain (separated by the Strait of Gibraltar; 14 km wide), indicated a possible biodiversity loss in the Moroccan forests.

  11. Modeling Forest Succession among Ecological Land Units in Northern Minnesota

    Directory of Open Access Journals (Sweden)

    George Host

    1998-12-01

    Full Text Available Field and modeling studies were used to quantify potential successional pathways among fine-scale ecological classification units within two geomorphic regions of north-central Minnesota. Soil and overstory data were collected on plots stratified across low-relief ground moraines and undulating sand dunes. Each geomorphic feature was sampled across gradients of topography or soil texture. Overstory conditions were sampled using five variable-radius point samples per plot; soil samples were analyzed for carbon and nitrogen content. Climatic, forest composition, and soil data were used to parameterize the sample plots for use with LINKAGES, a forest growth model that simulates changes in composition and soil characteristics over time. Forest composition and soil properties varied within and among geomorphic features. LINKAGES simulations were using "bare ground" and the current overstory as starting conditions. Northern hardwoods or pines dominated the late-successional communities of morainal and dune landforms, respectively. The morainal landforms were dominated by yellow birch and sugar maple; yellow birch reached its maximum abundance in intermediate landscape positions. On the dune sites, pine was most abundant in drier landscape positions, with white spruce increasing in abundance with increasing soil moisture and N content. The differences in measured soil properties and predicted late-successional composition indicate that ecological land units incorporate some of the key variables that govern forest composition and structure. They further show the value of ecological classification and modeling for developing forest management strategies that incorporate the spatial and temporal dynamics of forest ecosystems.

  12. Chemical characterization of garnets from Garnet Ridge, northern Arizona in the Colorado Plateau

    Science.gov (United States)

    Itaru, K.; Ogasawara, Y.

    2011-12-01

    Garnet crystals with diverse chemistries and their origins have occurred at Garnet Ridge in northern Arizona, Colorado Plateau. The garnet grains occur as small grains (2-5mm φ) scattering on weathered late Jurassic red mudstone, very large grained single crystal (1 to several cm), and major constituent minerals of eclogite and other garnet-bearing xenoliths in kimberlitic diatreme. The important discovery of coesite-bearing lawsonite eclogite, which is one of the source rocks of garnets, has been reported by Usui et al. (2005), and their zircon ages (81 to 33 Ma) suggest that the lawsonite eclogite was a product of subduction of the Fallaron plate underneath the Colorado Plateau. We collected several kinds of garnet grains with various origins and of xenoliths, and clarified the chemical characteristics of these garnets with an electron microprobe (JXA-8900 WDS mode). The garnet samples were classified into 6 groups: (A) scattered grains of reddish to purplish garnet (2-5 mm φ), (B) large-grained reddish brown garnet, (C) garnet in an eclogite xenolith. (D) garnet in unknown xenolith A, (E) garnet in unknown xenolith B, (F) garnet in garnet-clinopyroxene rock xenolith (strongly altered). The results of microprobe analyses showed the large difference in each garnet type on Prp-Alm-Grs triangular diagram. The garnet chemistries were as follows: (1) Type A garnets were relatively Prp-rich but have a wide range in Prp component. The Cr2O3 contents (max. 4 wt.%) divided this type into two groups. (2) Type-B garnets were plotted near the center of the triangle and did not show clear chemical zonation. (3) Type-C garnets have Alm-rich composition and were low in Prp. They show chemical zonation of Pyr and Grs components (MgO:1.4 to 5.4 wt.%, and CaO: 14.0 to 5.6 wt.% both from core to rim). Clinopyroxene is omphacite. (4) Type D garnets were plotted on Alm-Grs join (Grs61-71Alm23-35And5-7). (5) Type E garnets are characterized by very low Grs-components and were

  13. Fire risk and adaptation strategies in Northern Eurasian forests

    Science.gov (United States)

    Shvidenko, Anatoly; Schepaschenko, Dmitry

    2013-04-01

    On-going climatic changes substantially accelerate current fire regimes in Northern Eurasian ecosystems, particularly in forests. During 1998-2012, wildfires enveloped on average ~10.5 M ha year-1 in Russia with a large annual variation (between 3 and 30 M ha) and average direct carbon emissions at ~150 Tg C year-1. Catastrophic fires, which envelope large areas, spread in usually incombustible wetlands, escape from control and provide extraordinary negative impacts on ecosystems, biodiversity, economics, infrastructure, environment, and health of population, become a typical feature of the current fire regimes. There are new evidences of correlation between catastrophic fires and large-scale climatic anomalies at a continental scale. While current climatic predictions suggest the dramatic warming (at the average at 6-7 °C for the country and up to 10-12°C in some northern continental regions), any substantial increase of summer precipitation does not expected. Increase of dryness and instability of climate will impact fire risk and severity of consequences. Current models suggest a 2-3 fold increase of the number of fires by the end of this century in the boreal zone. They predict increases of the number of catastrophic fires; a significant increase in the intensity of fire and amount of consumed fuel; synergies between different types of disturbances (outbreaks of insects, unregulated anthropogenic impacts); acceleration of composition of the gas emissions due to enhanced soil burning. If boreal forests would become a typing element, the mass mortality of trees would increase fire risk and severity. Permafrost melting and subsequent change of hydrological regimes very likely will lead to the degradation and destruction of boreal forests, as well as to the widespread irreversible replacement of forests by other underproductive vegetation types. A significant feedback between warming and escalating fire regimes is very probable in Russia and particularly in the

  14. Northern homelands, northern frontier: linking culture and economic security in contemporary livelihoods in boreal and cold temperate forest communities in northern Canada

    Science.gov (United States)

    Andrew J. Chapeskie

    2001-01-01

    This paper highlights the environmental pressures that have historically been brought to bear on the northern forests of Canada. It then presents the idea of the northern frontier forests of Canada as Indigenous landscapes whose ecological diversity and abundance have historically been nurtured in no small measure by their original inhabitants. It then proposes how...

  15. Variation in woody plant mortality and dieback from severe drought among soils, plant groups, and species within a northern Arizona ecotone.

    Science.gov (United States)

    Koepke, Dan F; Kolb, Thomas E; Adams, Henry D

    2010-08-01

    Vegetation change from drought-induced mortality can alter ecosystem community structure, biodiversity, and services. Although drought-induced mortality of woody plants has increased globally with recent warming, influences of soil type, tree and shrub groups, and species are poorly understood. Following the severe 2002 drought in northern Arizona, we surveyed woody plant mortality and canopy dieback of live trees and shrubs at the forest-woodland ecotone on soils derived from three soil parent materials (cinder, flow basalt, sedimentary) that differed in texture and rockiness. Our first of three major findings was that soil parent material had little effect on mortality of both trees and shrubs, yet canopy dieback of trees was influenced by parent material; dieback was highest on the cinder for pinyon pine (Pinus edulis) and one-seed juniper (Juniperus monosperma). Ponderosa pine (Pinus ponderosa) dieback was not sensitive to parent material. Second, shrubs had similar mortality, but greater canopy dieback, than trees. Third, pinyon and ponderosa pines had greater mortality than juniper, yet juniper had greater dieback, reflecting different hydraulic characteristics among these tree species. Our results show that impacts of severe drought on woody plants differed among tree species and tree and shrub groups, and such impacts were widespread over different soils in the southwestern U.S. Increasing frequency of severe drought with climate warming will likely cause similar mortality to trees and shrubs over major soil types at the forest-woodland ecotone in this region, but due to greater mortality of other tree species, tree cover will shift from a mixture of species to dominance by junipers and shrubs. Surviving junipers and shrubs will also likely have diminished leaf area due to canopy dieback.

  16. Mechanical suppression of northern pike (Esox lucius) populations in small Arizona reservoirs

    Science.gov (United States)

    Kuzmenko, Yuliya; Spesiviy, Timofy; Bonar, Scott A.

    2010-01-01

    Introduced populations of northern pike Esox lucius have provided angling opportunities in the western United States (McMahon and Bennett 1996). However, the northern pike is a voracious piscivore and its large size, high fecundity, and broad physiological tolerance make it capable of drastically altering ecosystems it invades (Marchetti et al. 2004). Indeed, predation by northern pike has been shown to significantly alter fish community structure and put native fishes at a higher extinction risk (He and Kitchell 1990, Findlay et al. 2000). Predation by northern pike is viewed as a significant threat to native stocks of salmonids in Washington, British Columbia, and California (McMahon and Bennett 1996, California Department of Fish and Game [CDFG] 2003).

  17. A Forest Tent Caterpillar Outbreak Increased Resource Levels and Seedling Growth in a Northern Hardwood Forest.

    Science.gov (United States)

    Rozendaal, Danaë M A; Kobe, Richard K

    2016-01-01

    In closed-canopy forests, gap formation and closure are thought to be major drivers of forest dynamics. Crown defoliation by insects, however, may also influence understory resource levels and thus forest dynamics. We evaluate the effect of a forest tent caterpillar outbreak on understory light availability, soil nutrient levels and tree seedling height growth in six sites with contrasting levels of canopy defoliation in a hardwood forest in northern lower Michigan. We compared resource levels and seedling growth of six hardwood species before, during and in the three years after the outbreak (2008-2012). Canopy openness increased strongly during the forest tent caterpillar outbreak in the four moderately and severely defoliated sites, but not in lightly defoliated sites. Total inorganic soil nitrogen concentrations increased in response to the outbreak in moderately and severely defoliated sites. The increase in total inorganic soil nitrogen was driven by a strong increase in soil nitrate, and tended to become stronger with increasing site defoliation. Seedling height growth increased for all species in the moderately and severely defoliated sites, but not in lightly defoliated sites, either during the outbreak year or in the year after the outbreak. Growth increases did not become stronger with increasing site defoliation, but were strongest in a moderately defoliated site with high soil nutrient levels. Growth increases tended to be strongest for the shade intolerant species Fraxinus americana and Prunus serotina, and the shade tolerant species Ostrya virginiana. The strong growth response of F. americana and P. serotina suggests that recurring forest tent caterpillar outbreaks may facilitate the persistence of shade intolerant species in the understory in the absence of canopy gaps. Overall, our results suggest that recurrent canopy defoliation resulting from cyclical forest insect outbreaks may be an additional driver of dynamics in temperate closed

  18. REMOTE SENSING IN NORTHERN ARIZONA: S. P. CINDER CONE AND LAVA FLOW.

    Science.gov (United States)

    Schaber, Gerald C.; Kozak, R.C.; Burns, Barbara A.; Bartels, K.I.

    1984-01-01

    The objective of this poster paper is to present a site-specific atlas showing a wide variety of remote sensing data sets collected for the area of S. P. Mountain and lava flow (basaltic-andesite) in north-central Arizona. The data set to be displayed includes a number of radar images, representing three wavelength regions (1-, 3- and 25-cm), multiple incidence angles, look directions, and polarization combinations, in addition to thermal infrared scanner imagery, multispectral scanner imagery, aerial and ground photography, micro- and macro topography, and four-frequency, multipolarization radar scatterometer spectra. The expression of different surface units on the S. P. lava flow are effectively displayed on the ERIM four-channel images by the registration and combination of the four bands. Multi-color imagery of band combinations demonstrate the information content of multi-channel SAR imagery as well as the suitability of extending data manipulation methods developed for Landsat data to SAR data.

  19. Analysis of airborne LiDAR surveys to quantify the characteristic morphologies of northern forested wetlands

    Science.gov (United States)

    Murray C. Richardson; Carl P. J. Mitchell; Brian A. Branfireun; Randall K. Kolka

    2010-01-01

    A new technique for quantifying the geomorphic form of northern forested wetlands from airborne LiDAR surveys is introduced, demonstrating the unprecedented ability to characterize the geomorphic form of northern forested wetlands using high-resolution digital topography. Two quantitative indices are presented, including the lagg width index (LWI) which objectively...

  20. Preliminary bedrock and surficial geologic map of the west half of the Sanders 30' x 60' quadrangle, Navajo and Apache Counties, northern Arizona

    Science.gov (United States)

    Amoroso, Lee; Priest, Susan S.; Hiza-Redsteer, Margaret

    2014-01-01

    The bedrock and surficial geologic map of the west half of the Sanders 30' x 60' quadrangle was completed in a cooperative effort of the U.S. Geological Survey (USGS) and the Navajo Nation to provide regional geologic information for management and planning officials. This report provides baseline geologic information that will be useful in future studies of groundwater and surface water resources, geologic hazards, and the distribution of soils and plants. The west half of the Sanders quadrangle encompasses approximately 2,509 km2 (980 mi2) within Navajo and Apache Counties of northern Arizona and is bounded by lat 35°30' to 35° N., long 109°30' to 110° W. The majority of the land within the map area lies within the Navajo Nation. South of the Navajo Nation, private and State lands form a checkerboard pattern east and west of Petrified Forest National Park. In the west half of the Sanders quadrangle, Mesozoic bedrock is nearly flat lying except near folds. A shallow Cenozoic erosional basin that developed about 20 Ma in the western part of the map area cut across late Paleozoic and Mesozoic rocks that were subsequently filled with flat-lying Miocene and Pliocene mudstone and argillaceous sandstone and fluvial sediments of the Bidahochi Formation and associated volcanic rocks of the Hopi Buttes volcanic field. The Bidahochi rocks are capped by Pliocene(?) and Pleistocene fluvial sediments and Quaternary eolian and alluvial deposits. Erosion along northeast-southwest-oriented drainages have exposed elongated ridges of Bidahochi Formation and basin-fill deposits that are exposed through shallow eolian cover of similarly oriented longitudinal dunes. Stokes (1964) concluded that the accumulation of longitudinal sand bodies and the development of confined parallel drainages are simultaneous processes resulting in parallel sets of drainages and ridges oriented along the prevailing southwest wind direction on the southern Colorado Plateau.

  1. Carbon Budget and its Dynamics over Northern Eurasia Forest Ecosystems

    Science.gov (United States)

    Shvidenko, Anatoly; Schepaschenko, Dmitry; Kraxner, Florian; Maksyutov, Shamil

    2016-04-01

    The presentation contains an overview of recent findings and results of assessment of carbon cycling of forest ecosystems of Northern Eurasia. From a methodological point of view, there is a clear tendency in understanding a need of a Full and Verified Carbon Account (FCA), i.e. in reliable assessment of uncertainties for all modules and all stages of FCA. FCA is considered as a fuzzy (underspecified) system that supposes a system integration of major methods of carbon cycling study (land-ecosystem approach, LEA; process-based models; eddy covariance; and inverse modelling). Landscape-ecosystem approach 1) serves for accumulation of all relevant knowledge of landscape and ecosystems; 2) for strict systems designing the account, 3) contains all relevant spatially distributed empirical and semi-empirical data and models, and 4) is presented in form of an Integrated Land Information System (ILIS). The ILIS includes a hybrid land cover in a spatially and temporarily explicit way and corresponding attributive databases. The forest mask is provided by utilizing multi-sensor remote sensing data, geographically weighed regression and validation within GEO-wiki platform. By-pixel parametrization of forest cover is based on a special optimization algorithms using all available knowledge and information sources (data of forest inventory and different surveys, observations in situ, official statistics of forest management etc.). Major carbon fluxes within the LEA (NPP, HR, disturbances etc.) are estimated based on fusion of empirical data and aggregations with process-based elements by sets of regionally distributed models. Uncertainties within LEA are assessed for each module and at each step of the account. Within method results of LEA and corresponding uncertainties are harmonized and mutually constrained with independent outputs received by other methods based on the Bayesian approach. The above methodology have been applied to carbon account of Russian forests for 2000

  2. Breccia-pipe uranium mining in northern Arizona; estimate of resources and assessment of historical effects

    Science.gov (United States)

    Bills, Donald J.; Brown, Kristin M.; Alpine, Andrea E.; Otton, James K.; Van Gosen, Bradley S.; Hinck, Jo Ellen; Tillman, Fred D

    2011-01-01

    About 1 million acres of Federal land in the Grand Canyon region of Arizona were temporarily withdrawn from new mining claims in July 2009 by the Secretary of the Interior because of concern that increased uranium mining could have negative impacts on the land, water, people, and wildlife. During a 2-year interval, a Federal team led by the Bureau of Land Management is evaluating the effects of withdrawing these lands for extended periods. As part of this team, the U.S. Geological Survey (USGS) conducted a series of short-term studies to examine the historical effects of breccia-pipe uranium mining in the region. The USGS studies provide estimates of uranium resources affected by the possible land withdrawal, examine the effects of previous breccia-pipe mining, summarize water-chemistry data for streams and springs, and investigate potential biological pathways of exposure to uranium and associated contaminants. This fact sheet summarizes results through December 2009 and outlines further research needs.

  3. Sustaining northern red oak forests: managing oak from regeneration to canopy dominance in mature stands

    Science.gov (United States)

    Daniel C. Dey; Gary W. Miller; John M. Kabrick

    2008-01-01

    Across the range of northern red oak, managers have problems sustaining current stocking of northern red oak in forests. Oak species are adapted to frequent stand disturbances that reduce the abundance of shade tolerant competitors and control fast-growing pioneer species. A widely recommended approach to regenerating northern red oak is to develop relatively large...

  4. Quality of water and estimates of water inflow, northern boundary area, Fort McDowell Indian Reservation, Maricopa County, Arizona

    Science.gov (United States)

    Hoffmann, John P.; O'Day, Christie M.

    2001-01-01

    Increased agricultural and recreational activities and recent growth of population centers within the Verde River basin have led to concerns about the quality and quantity of water flowing onto the Fort McDowell Indian Reservation. The purpose of this study was to determine the quality and quantity of water in the Verde River and in the shallow stream-channel deposits in the vicinity of the northern boundary of the reservation. The quality of surface water entering the reservation at the northern boundary and of ground water in the shallow stream- channel deposits beneath the flood plain is suitable for most purposes. Concentrations of dissolved solids and major ions did not exceed water-quality standards. Dissolved oxygen and pH generally were in acceptable ranges for all designated uses. Total coliform counts and nutrient concentrations also did not exceed water-quality standards. Six organic compounds were detected; however, concentrations of these compounds were below U.S. Environmental Protection Agency Maximum Contaminant Levels. The presence of these organic compounds indicates that the water has been affected by anthropogenic activities. Concentrations of all trace metals were below the applicable State of Arizona Water Quality Standards for Surface Water and U.S. Environmental Protection Agency Maximum Contaminant Levels. Arsenic concentrations were below the Maximum Contaminant Level of 50 micrograms per liter at the time of collection and analysis; however, in January 2001, the U.S. Environmental Protection Agency set a new Maximum Contaminant Level of 10 micrograms per liter. All arsenic concentrations in surface water were 10 micrograms per liter or greater. Arsenic concentra-tion in ground water ranged from 6 to 9 micrograms per liter. The source of arsenic is probably oxidized arsenic compounds that are typically found in basin-fill sediments in southern Arizona. Surface-water flow onto the reservation was determined from recorded discharge at the

  5. Presence of the dinosaur Scelidosaurus indicates Jurassic age for the Kayenta Formation (Glen Canyon Group, northern Arizona)

    Science.gov (United States)

    Padian, Kevin

    1989-05-01

    The Glen Canyon Group (Moenave, Wingate, Kayenta and Navajo Formations) of northern Arizona represents an extensive outcrop of early Mesozoic age terrestrial sediments. The age of these formations has long been disputed because independent stratigraphic data from marine tie-ins, paleobotanical and palynological evidence, and radiometric calibrations have been scanty or absent. The fauna of the Kayenta Formation in particular has been problematic because it has appeared to contain both typical Late Triassic and Early Jurassic taxa Here I report that the principal evidence for Late Triassic taxa, dermal scutes previously assigned to an aetosaur, in fact belongs to the thyreophoran ornithischian dinosaur Scelidosaurus, previously known only as a washed-in form found in marine sediments in the Early Jurassic of England. The presence of this dinosaur represents the first vertebrate biostratigraphic tie-in of the Glen Canyon Group horizons with reliably dated marine deposits in Europe. Together with revised systematic assessments of other vertebrates and independent evidence from fossil pollen, it supports an Early Jurassic age for the Kayenta Formation and most or all of the Glen Canyon Group.

  6. Utility of high-altitude infrared spectral data in mineral exploration: Application to Northern Patagonia Mountains, Arizona

    Science.gov (United States)

    Berger, B.R.; King, T.V.V.; Morath, L.C.; Phillips, J.D.

    2003-01-01

    Synoptic views of hydrothermal alteration assemblages are of considerable utility in regional-scale minerals exploration. Recent advances in data acquisition and analysis technologies have greatly enhanced the usefulness of remotely sensed imaging spectroscopy for reliable alteration mineral assemblages mapping. Using NASA's Airborne Visible Infrared Imaging Spectrometer (AVIRIS) sensor, this study mapped large areas of advanced argillic and phyllic-argillic alteration assemblages in the southeastern Santa Rita and northern Patagonia mountains, Arizona. Two concealed porphyry copper deposits have been identified during past exploration, the Red Mountain and Sunnyside deposits, and related published hydrothermal alteration zoning studies allow the comparison of the results obtained from AVIRIS data to the more traditional field mapping approaches. The AVIRIS mapping compares favorably with field-based studies. An analysis of iron-bearing oxide minerals above a concealed supergene chalcocite deposit at Red Mountain also indicates that remotely sensed data can be of value in the interpretation of leached caps above porphyry copper deposits. In conjunction with other types of geophysical data, AVIRIS mineral maps can be used to discriminate different exploration targets within a region.

  7. Forest conflict in Thailand: northern minorities in focus.

    Science.gov (United States)

    Hares, Minna

    2009-03-01

    This paper aims at exploring the local background of and solutions to the forest conflict in upland areas inhabited by ethnic minorities, who are called hill tribes, in northern Thailand. A so-called hill tribe problem has been officially identified as a result of the slash-and-burn cultivation and other perceived problems, such as opium poppy cultivation, illegal immigration, and the suspicion of disloyalty to the state. This has created distrust and tension between the groups and authorities. The local conflict has recently been related to the dilemma of conserving the forest from all human interference, while many people live and make their livelihood within and adjacent to the protected areas. Furthermore, as the results imply, strictly protected areas and reforestation have also increased the competition over land and natural resources and, thereby, the likelihood of local conflicts. The scarcity and pollution of water, illegal logging, and poor fire control have contributed to the conflicts between local communities. The conflicts between the local communities and officials have been nourished by political and public discussions. Using definitions and terms with negative connotations and ignoring the heterogeneity between the groups or labeling some groups as malevolent have increased distrust and strengthened existing stereotypical images. Conflict resolution starts with efforts toward better mutual understanding, and changes in structures and attitudes are necessary. Local cooperation, utilization of traditional methods, and local institutions are central to conflict solving.

  8. Forest Conflict in Thailand: Northern Minorities in Focus

    Science.gov (United States)

    Hares, Minna

    2009-03-01

    This paper aims at exploring the local background of and solutions to the forest conflict in upland areas inhabited by ethnic minorities, who are called hill tribes, in northern Thailand. A so-called hill tribe problem has been officially identified as a result of the slash-and-burn cultivation and other perceived problems, such as opium poppy cultivation, illegal immigration, and the suspicion of disloyalty to the state. This has created distrust and tension between the groups and authorities. The local conflict has recently been related to the dilemma of conserving the forest from all human interference, while many people live and make their livelihood within and adjacent to the protected areas. Furthermore, as the results imply, strictly protected areas and reforestation have also increased the competition over land and natural resources and, thereby, the likelihood of local conflicts. The scarcity and pollution of water, illegal logging, and poor fire control have contributed to the conflicts between local communities. The conflicts between the local communities and officials have been nourished by political and public discussions. Using definitions and terms with negative connotations and ignoring the heterogeneity between the groups or labeling some groups as malevolent have increased distrust and strengthened existing stereotypical images. Conflict resolution starts with efforts toward better mutual understanding, and changes in structures and attitudes are necessary. Local cooperation, utilization of traditional methods, and local institutions are central to conflict solving.

  9. Productivity of Northern Eurasian forests: Analysis of uncertainties

    Science.gov (United States)

    Shvidenko, Anatoly; Schepaschenko, Dmitry; McCallum, Ian

    2010-05-01

    Indicators of biological productivity of forests (live and dead biomass, net primary production, net and gross growth) are crucial for both assessment of the impacts of terrestrial ecosystems on major biogeochemical cycles and practice of sustainable forest management. However, different information and the diversity of methods used in the assessments of forests productivity cause substantial variation in reported estimates. The paper contains a systems analysis of the existing methods, their uncertainties, and a description of available information. With respect to Northern Eurasian forests, the major reasons for uncertainties could be categorized as following: (1) significant biases that are inherent in a number of important sources of available information (e.g., forest inventory data, results of measurements of some indicators in situ); (2) inadequacy and oversimplification of models of different types (empirical aggregations, process-based models); (3) lack of data for some regions; and (4) upscaling procedure of 'point' observations. Based on as comprehensive as possible adherence to the principles of systems analysis, we made an attempt to provide a reanalysis of indicators of forests productivity of Russia aiming at obtaining the results for which uncertainties could be estimated in a reliable and transparent way. Within a landscape-ecosystem approach it has required (1) development of an expert system for refinement of initial data including elimination of recognized biases; (2) delineation of ecological regions based on gradients of major indicators of productivity; (3) transition to multidimensional models (e.g., for calculation of spatially distributed biomass expansion factors); (4) use of process-based elements in empirical models; and (5) development of some approaches which presumably do not have recognized biases. However, taking into account the fuzzy character of the problem, the above approach (as well as any other individually used method) is

  10. Landscape variation in tree species richness in northern Iran forests.

    Directory of Open Access Journals (Sweden)

    Charles P-A Bourque

    Full Text Available Mapping landscape variation in tree species richness (SR is essential to the long term management and conservation of forest ecosystems. The current study examines the prospect of mapping field assessments of SR in a high-elevation, deciduous forest in northern Iran as a function of 16 biophysical variables representative of the area's unique physiography, including topography and coastal placement, biophysical environment, and forests. Basic to this study is the development of moderate-resolution biophysical surfaces and associated plot-estimates for 202 permanent sampling plots. The biophysical variables include: (i three topographic variables generated directly from the area's digital terrain model; (ii four ecophysiologically-relevant variables derived from process models or from first principles; and (iii seven variables of Landsat-8-acquired surface reflectance and two, of surface radiance. With symbolic regression, it was shown that only four of the 16 variables were needed to explain 85% of observed plot-level variation in SR (i.e., wind velocity, surface reflectance of blue light, and topographic wetness indices representative of soil water content, yielding mean-absolute and root-mean-squared error of 0.50 and 0.78, respectively. Overall, localised calculations of wind velocity and surface reflectance of blue light explained about 63% of observed variation in SR, with wind velocity accounting for 51% of that variation. The remaining 22% was explained by linear combinations of soil-water-related topographic indices and associated thresholds. In general, SR and diversity tended to be greatest for plots dominated by Carpinus betulus (involving ≥ 33% of all trees in a plot, than by Fagus orientalis (median difference of one species. This study provides a significant step towards describing landscape variation in SR as a function of modelled and satellite-based information and symbolic regression. Methods in this study are sufficiently

  11. Hydrology of Area 62, Northern Great Plains and Rocky Mountain Coal Provinces, New Mexico and Arizona

    Science.gov (United States)

    Roybal, F.E.; Wells, J.G.; Gold, R.L.; Flager, J.V.

    1984-01-01

    This report summarizes available hydrologic data for Area 62 and will aid leasing decisions, and the preparation and appraisal of environmental impact studies and mine-permit applications. Area 62 is located at the southern end of the Rocky Mountain Coal Province in parts of New Mexico and Arizona and includes approximately 9,500 square miles. Surface mining alters, at least temporarily, the environment; if the areas are unreclaimed, there can be long-term environmental consequences. The land-ownership pattern in Area 62 is complicated. The checkerboard pattern created by several types of ownership makes effective management of these lands difficult. The climate generally is semiarid with average annual precipitation ranging from 10 to 20 inches. Pinons, junipers, and grasslands cover most of the area, and much of it is used for grazing by livestock. Soils vary with landscape, differing from flood plains and hillslopes to mountain slopes. The major structural features of this area were largely developed during middle Tertiary time. The main structural features are the southern San Juan Basin and the Mogollon slope. Coal-bearing rocks are present in four Cretaceous rock units of the Mesaverde Group: the Gallup Sandstone, the Dileo Coal Member, and the Gibson Coal Member of the Crevasse Canyon Formation, and the Cleary Coal Member of the Menefee Formation. Area 62 is drained by Black Creek, the Puerco River, the Zuni River, Carrizo Wash-Largo Creek, and the Rio San Jose. Only at the headwaters of the Zuni River is the flow perennial. The streamflow-gaging station network consists of 25 stations operated for a variety of needs. Streamflow changes throughout the year with variation related directly to rainfall and snowmelt. Base flow in Area 62 is zero indicating no significant ground-water discharge. Mountainous areas contribute the highest mean annual runoff of 1.0 inch. Very few water-quality data are available for the surface-water stations. Of the nine surface

  12. Influence of different tree-harvesting intensities on forest soil carbon stocks in boreal and northern temperate forest ecosystems

    DEFF Research Database (Denmark)

    Clarke, Nicholas; Gundersen, Per; Jönsson-Belyazid, Ulrika;

    2015-01-01

    Effective forest governance measures are crucial to ensure sustainable management of forests, but so far there has been little specific focus in boreal and northern temperate forests on governance measures in relation to management effects, including harvesting effects, on soil organic carbon (SOC......) stocks. This paper reviews the findings in the scientific literature concerning the effects of harvesting of different intensities on SOC stocks and fluxes in boreal and northern temperate forest ecosystems to evaluate the evidence for significant SOC losses following biomass removal. An overview...... of existing governance measures related to SOC is given, followed by a discussion on how scientific findings could be incorporated in guidelines and other governance measures. The currently available information does not support firm conclusions about the long-term impact of intensified forest harvesting...

  13. Ash-flow tuffs of the Galiuro Volcanics in the northern Galiuro Mountains, Pinal County, Arizona

    Science.gov (United States)

    Krieger, Medora Louise Hooper

    1979-01-01

    The upper Oligocene and lower Miocene Galiuro Volcanics in the northern part of the Galiuro Mountains contains two distinctive major ash-flow tuff sheets, the Holy Joe and Aravaipa Members. These major ash-flows illustrate many features of ash-flow geology not generally exposed so completely. The Holy Joe Member, composed of a series of densely welded flows of quartz latite composition that make up a simple cooling unit. is a rare example of a cooling unit that has a vitrophyre at the top as well as at the base. The upper vitrophyre does not represent a cooling break. The Aravaipa Member. a rhyolite, is completely exposed in Aravaipa and other canyons and on Table Mountain. Remarkable exposures along Whitewash Canyon exhibit the complete change from a typical stacked-up interior zonation of an ash flow to a non welded distal margin. Vertical and horizontal changes in welding, crystallization, specific gravity, and lithology are exposed. The ash flow can be divided into six lithologic zones. The Holy Joe and Aravaipa Members of the Galiuro Volcanics are so well exposed and so clearly show characteristic features of ash-flow tuffs that they could be a valuable teaching aid and a source of theses for geology students.

  14. Climate change in the western and northern forests of Canada: Impacts and adaptations

    Energy Technology Data Exchange (ETDEWEB)

    McKinnon, G. A.; Webber, S. L.; MacKendrick, N. A. [Natural Resources Canada, Canadian Forest Service, Northern Forestry Centre, Edmonton, AB (Canada)

    2004-07-01

    This report contains summaries of papers presented at the Workshop on Climate Change in the Western and Northern Forests of Canada, held on February 17-19, 2003, in Prince George BC. The workshop provided an opportunity for the exchange of views on the expected impacts of climate change on Canada's western and northern forests, and potential adaptive strategies. Several papers also dealt with the implications of climate change on environmental, social, and economic values of the forest, and institutional barriers to adaptation. Six key topics were addressed in informal 'knowledge cafe sessions': forest fires, insects and disease, forest productivity, forest practices, biodiversity, and non-timber forest values. Another informal series of meetings, dubbed 'open space sessions' centred around managing the various mechanisms, organizations, and stakeholders involved in climate change research and adaptation strategies. Lists containing the names of authors, and of workshop participants are also included.

  15. Geochemistry of middle Tertiary volcanic rocks in the northern Aquarius Mountains, west-central Arizona

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, A.M.; Haxel, G.B.

    1993-04-01

    The northern Aquarius Mountains volcanic field ([approximately]50km east of Kingman) covers an area of 400 km[sup 2], bounded by upper Trout Creek (S), the Truxton Valley (N), the Big Sandy Valley (W), and Cross Mountain (E). The volcanic sequence rests upon a pre-middle Eocene erosional surface. The lowest units is a 250 m-thick unit of rhyolitic pyroclastic breccias and airfall tuffs. Successively younger units are: basanite flows and cinder cones; hornblende latite flows and domes; porphyritic dacite flows, domes, and breccias; alkali basalt intrusions; and low-silica rhyolite domes and small high=silica rhyolite flows. Dacite is volumetrically dominant, and erupted primarily from vents in and around Cedar Basin (Penitentiary Mtn 7.5[prime] quad.). Other geologists have obtained K-Ar dates [approximately]24--20 Ma for the basanites and latites. The alkali basalts, latites, dacites, and rhyolites evidently constitute a genetically-related high-K to shoshonitic calcalkaline suite with chemistry typical of subduction-related magmatism: enrichment in LILE and LREE, and depletion of Nb and Ta relative to K and La and of Ti relative to Hf and Yb. Each rock type is unique and distinguishable in K/Rb and Rb/Sr. The basanites are primitive (mg=0.75--0.78), have intraplate affinities (La/Nb[<=]1), and show consistent and distinctive depletion of K relative to the other LILE. The presence of these basanites in an early Miocene volcanic sequence is unusual or unexpected, as they predate (by [approximately]10 m.y.) the regional eruption of asthenosphere-derived basalts associated with Basin-and-Range extension.

  16. VT Lakeshore Land Cover Land Use for Northern Forest Area - lakes only

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This feature dataset contains layers created for an analysis of lakeshore development in the Northern Forest of Vermont by the University of...

  17. VT Lakeshore Land Cover Land Use for Northern Forest Area - all areas

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) This feature dataset contains layers created for an analysis of lakeshore development in the Northern Forest of Vermont by the University of...

  18. Contrasting responses of epiphytic and terricolous lichens to variations in forest characteristics in northern boreal ecosystems

    National Research Council Canada - National Science Library

    Boudreault, Catherine; Drapeau, Pierre; Bouchard, Mathieu; St-Laurent, Martin-Hugues; Imbeau, Louis; Bergeron, Yves

    2015-01-01

    ...) on fruticose epiphytic and terricolous lichen communities across a large region located at the interface between closed-crown boreal forests and northern open woodlands in the province of Quebec (Canada...

  19. Fuel treatment impacts on estimated wildfire carbon loss from forests in Montana, Oregon, California, and Arizona

    Science.gov (United States)

    Stephens, Scott L.; Boerner, Ralph E.J.; Maghaddas, Jason J.; Maghaddas, Emily E.Y.; Collins, Brandon M.; Dow, Christopher B.; Edminster, Carl; Fiedler, Carl E.; Fry, Danny L.; Hartsough, Bruce R.; Keeley, Jon E.; Knapp, Eric E.; McIver, James D.; Skinner, Carl N.; Youngblood, Andrew P.

    2012-01-01

    Using forests to sequester carbon in response to anthropogenically induced climate change is being considered across the globe. A recent U.S. executive order mandated that all federal agencies account for sequestration and emissions of greenhouse gases, highlighting the importance of understanding how forest carbon stocks are influenced by wildfire. This paper reports the effects of the most common forest fuel reduction treatments on carbon pools composed of live and dead biomass as well as potential wildfire emissions from six different sites in four western U.S. states. Additionally, we predict the median forest product life spans and uses of materials removed during mechanical treatments. Carbon loss from modeled wildfire-induced tree mortality was lowest in the mechanical plus prescribed fire treatments, followed by the prescribed fire-only treatments. Wildfire emissions varied from 10–80 Mg/ha and were lowest in the prescribed fire and mechanical followed by prescribed fire treatments at most sites. Mean biomass removals per site ranged from approximately 30–60 dry Mg/ha; the median lives of products in first use varied considerably (from 50 years). Our research suggests most of the benefits of increased fire resistance can be achieved with relatively small reductions in current carbon stocks. Retaining or growing larger trees also reduced the vulnerability of carbon loss from wildfire. In addition, modeled vulnerabilities to carbon losses and median forest product life spans varied considerably across our study sites, which could be used to help prioritize treatment implementation.

  20. Simulation of groundwater withdrawal scenarios for the Redwall-Muav and Coconino Aquifer Systems of northern and central Arizona

    Science.gov (United States)

    Pool, D.R.

    2016-09-23

    The Northern Arizona Regional Groundwater Flow Model was used to estimate the hydrologic changes, including water-level change and groundwater discharge to streams and springs, that may result from future changes in groundwater withdrawals in and near the Coconino Plateau Water Advisory Council study area, Coconino and Navajo Counties, Arizona. Three future groundwater withdrawal scenarios for tribal and nontribal uses were developed by the Coconino Plateau Water Advisory Council and were simulated for the period representing the years from 2006 through 2105. Scenario 1 assumes no major changes in groundwater use except for increased demand based on population projections. Scenario 2 assumes that a pipeline will provide a source of surface water from Lake Powell to areas near Cameron and Moenkopi that would replace local groundwater withdrawals. Scenario 3 assumes that the pipeline extends to the Flagstaff and Williams areas, and would replace groundwater demands for water in the area.The Coconino Plateau Water Advisory Council withdrawal scenarios primarily influence water levels and groundwater discharge in the Coconino Plateau basin, near the western margin of the Little Colorado River Plateau basin, and the Verde Valley subbasin. Simulated effects of the withdrawal scenarios are superimposed on effects of previous variations in groundwater withdrawals and artificial and incidental recharge. Pre-scenario variations include changes in water-levels in wells; groundwater storage; discharge to streams and springs; and evapotranspiration by plants that use groundwater. Future variations in groundwater discharge and water-levels in wells will continue to occur as a result of both the past and any future changes.Water-level variations resulting from post-2005 stresses, including groundwater withdrawals and incidental and artificial recharge, in the area of the withdrawal scenarios are primarily localized and superimposed on the regional changes caused by variations in

  1. The palynology of the Sonsela member (Late Triassic, Norian) at Petrified Forest National Park, Arizona, USA

    NARCIS (Netherlands)

    Reichgelt, T.; Parker, W.G.; Martz, J.W.; Conran, J.G.; van Konijnenburg-van Cittert, J.H.A.; Kürschner, W.M.

    2013-01-01

    Recent paleontological investigations and lithostratigraphic revisions reveal a marked biotic turnover zone within the continental deposits of the Sonsela member of the Chinle Formation (Late Triassic, Norian) at Petrified Forest National Park, USA. Within the Sonsela member we found three pollen as

  2. 75 FR 9388 - Prescott National Forest, Bradshaw Ranger District; Arizona; Bradshaw Vegetation Management Project

    Science.gov (United States)

    2010-03-02

    ... Management Project AGENCY: Forest Service, USDA. ACTION: Notice of intent to prepare an environmental impact statement. SUMMARY: This project is a proposal to improve the health of fire adapted ecosystems while simultaneously reducing hazardous fuels on the Bradshaw Ranger District. The project area encompasses about 55...

  3. Vegetation assessment of forests of Pagan Island, Commonwealth of the Northern Mariana Islands

    Science.gov (United States)

    Pratt, Linda W.

    2011-01-01

    As part of the Marianas Expedition Wildlife Surveys-2010, the forest vegetation of the island of Pagan, Commonwealth of the Northern Mariana Islands (CNMI), was sampled with a series of systematic plots along 13 transects established for monitoring forest bird populations. Shrubland and grassland were also sampled in the northern half of the island. Data collected were woody plant density, tree diameter at breast height, woody plant density in height classes below 2 m, and ground cover measured with the point-intercept method. Coconut forests (Cocos nucifera) were generally found to have low native tree diversity, little regeneration of trees and shrubs in the forest understory, and little live ground cover. The sole exception was a coconut-dominated forest of the northeast side of the island that exhibited high native tree diversity and a large number of young native trees in the understory. Ironwood (Casuarina equisetifolia) forests on the northern half of the island were nearly monocultures with almost no trees other than ironwood in vegetation plots, few woody plants in the understory, and low ground cover dominated by native ferns. Mixed native forests of both northern and southern sections of the island had a diversity of native tree species in both the canopy and the sparse understory. Ground cover of native forests in the north had a mix of native and alien species, but that of the southern half of the island was dominated by native ferns and woody plants.

  4. Data base for early postfire succession in Northern Rocky Mountain forests

    Science.gov (United States)

    Peter F. Stickney; Robert B. Campbell

    2000-01-01

    Web site and CD-ROM include 21 pages of text plus electronic data for 55 succession sites including color plates, tables, and figures. Provides data on quantitative postfire changes of plant species and forest vegetation components for up to the first 25 years of secondary plant succession for 55 forest sites in northern Idaho and northwestern Montana. Cover (aerial...

  5. Impacts of harvesting forest residues for bioenergy on nutrient cycling and community assemblages in northern hardwood forests

    Energy Technology Data Exchange (ETDEWEB)

    Donner, D.M.; Zalesny, R.S. [United States Dept. of Agriculture Forest Service, Rhinelander, WI (United States). Northern Research Station, Inst. for Applied Ecosystem Studies; St Pierre, M.; Eklund, D. [Chequamegon-Nicolet National Forest, Rhinelander, WI (United States); Coyle, D.R. [Wisconsin Univ., Madison, WI (United States). Dept. of Entomology; Ribic, C.A. [Wisconsin Univ., Madison, WI (United States). United States Geological Survey, WI Cooperative Wildlife Research Unit

    2010-07-01

    This study assessed the impacts of whole-tree harvesting on the nutrient cycles and community assemblages in northern hardwood forests. The woody biomass left on the forest floor after logging is important for nutrient cycling in addition to providing seed beds and creating habitats for wildlife. The impact of fine woody debris (FWD) removal on nutrient availability and above and below ground community assemblages on rich soils in regenerating northern hardwood stands in Wisconsin was investigated at 9 sites within a national forest. Soil carbon and nitrogen availability was assessed. Insect pitfalls, amphibian time-constraint searches, herbaceous plant quadrants, and soil cores along transects were sampled during the summer months of 2009. Results of the study will be used to evaluate the trade-offs of harvesting woody biomass on public lands for energy use as well as to develop management guidelines for maintaining biodiversity and forest health.

  6. Factors influencing density of the Northern Mealy Amazon in three forest types of a modified rainforest landscape in Mesoamerica

    Directory of Open Access Journals (Sweden)

    Miguel Ángel. De Labra-Hernández

    2017-06-01

    Full Text Available The high rate of conversion of tropical moist forest to secondary forest makes it imperative to evaluate forest metric relationships of species dependent on primary, old-growth forest. The threatened Northern Mealy Amazon (Amazona guatemalae is the largest mainland parrot, and occurs in tropical moist forests of Mesoamerica that are increasingly being converted to secondary forest. However, the consequences of forest conversion for this recently taxonomically separated parrot species are poorly understood. We measured forest metrics of primary evergreen, riparian, and secondary tropical moist forest in Los Chimalapas, Mexico. We also used point counts to estimate density of Northern Mealy Amazons in each forest type during the nonbreeding (Sept 2013 and breeding (March 2014 seasons. We then examined how parrot density was influenced by forest structure and composition, and how parrots used forest types within tropical moist forest. Overall, parrot density was high in the breeding season, with few parrots present during the nonbreeding season. During the breeding season, primary forest had significantly greater density of 18.9 parrots/km² in evergreen forest and 35.9 parrots/km² in riparian forest, compared with only 3.4 parrots/km² in secondary forest. Secondary forest had significantly lower tree species richness, density, diameter, total height, and major branch ramification height, as well as distinct tree species composition compared with both types of primary forest. The number of parrots recorded at point counts was related to density of large, tall trees, characteristic of primary forest, and parrots used riparian forest more than expected by availability. Hence, the increased conversion of tropical moist forest to secondary forest is likely to lead to reduced densities of forest-dependent species such as the Northern Mealy Amazon. Furthermore, the species' requirement for primary tropical moist forest highlights the need to reevaluate

  7. Part A: Geochemistry of Soil Samples from 50 Solution-Collapse Features on the Coconino Plateau, Northern Arizona

    Science.gov (United States)

    Van Gosen, Bradley S.; Wenrich, Karen J.

    1991-01-01

    Soil sampling surveys were conducted during 1984-1986 across 50 solution-collapse features exposed on the Coconino Plateau of northern Arizona in order to determine whether soil geochemistry can be used to distinguish mineralized breccia pipes from unmineralized collapse features. The 50 sampled features represent the variety of collapse features that crop out on plateau surfaces in northwestern Arizonaoodeeplyorooted solution-collapse breccia pipes, near-surface gypsum collapses, and sinkholes. Of the 50 features that were sampled in this study, 3 are confirmed breccia pipes that contain significant uranium and base-metal minerals, I is believed to be a sinkhole with no economic potential, and 4 are stratabound copper deposits whose possible relationship to breccia pipes is yet to be determined. The remaining collapse features are suspected to overlie breccia pipes, although some of these may represent near surface gypsum collapse features. However, no exploratory drilling results or breccia exposures exist to indicate their underlying structure. The low cost and ease of soil sampling suggested that this technique be evaluated for breccia pipe exploration. This report provides the locations and geochemical results for the soil sampling surveys and brief descriptions of the 50 collapse features. The analytical results of almost 2,000 soil samples are provided in tabular hardcopy and dBase III Plus diskcopy format. The analytical data is provided in digital format to allow the reader to choose their own methods for evaluating the effectiveness of soil sampling over known and suspected breccia pipes. A pilot survey conducted over 17 collapse features in 1984 suggested that soil sampling might be useful in distinguishing mineralized breccia pipes from other circular features. Followup detailed surveys in 1985 and 1986 used a radial sampling pattern at each of 50 sites; at least one third of the samples were collected from areas outside of the collapse feature to

  8. Part D: Geochemistry of Soil Samples from 50 Solution-Collapse Features on the Coconino Plateau, Northern Arizona

    Science.gov (United States)

    Van Gosen, Bradley S.; Wenrich, Karen J.

    1991-01-01

    Soil sampling surveys were conducted during 1984-1986 across 50 solution-collapse features exposed on the Coconino Plateau of northern Arizona in order to determine whether soil geochemistry can be used to distinguish mineralized breccia pipes from unmineralized collapse features. The 50 sampled features represent the variety of collapse features that crop out on plateau surfaces in northwestern Arizonaoodeeplyorooted solution-collapse breccia pipes, near-surface gypsum collapses, and sinkholes. Of the 50 features that were sampled in this study, 3 are confirmed breccia pipes that contain significant uranium and base-metal minerals, I is believed to be a sinkhole with no economic potential, and 4 are stratabound copper deposits whose possible relationship to breccia pipes is yet to be determined. The remaining collapse features are suspected to overlie breccia pipes, although some of these may represent near surface gypsum collapse features. However, no exploratory drilling results or breccia exposures exist to indicate their underlying structure. The low cost and ease of soil sampling suggested that this technique be evaluated for breccia pipe exploration. This report provides the locations and geochemical results for the soil sampling surveys and brief descriptions of the 50 collapse features. The analytical results of almost 2,000 soil samples are provided in tabular hardcopy and dBase III Plus diskcopy format. The analytical data is provided in digital format to allow the reader to choose their own methods for evaluating the effectiveness of soil sampling over known and suspected breccia pipes. A pilot survey conducted over 17 collapse features in 1984 suggested that soil sampling might be useful in distinguishing mineralized breccia pipes from other circular features. Followup detailed surveys in 1985 and 1986 used a radial sampling pattern at each of 50 sites; at least one third of the samples were collected from areas outside of the collapse feature to

  9. Ground Penetrating Radar Field Studies of Lunar-Analog Geologic Settings and Processes: Barringer Meteor Crater and Northern Arizona Volcanics

    Science.gov (United States)

    Russell, P. S.; Grant, J. A.; Williams, K. K.; Bussey, B.

    2010-12-01

    Ground-Penetrating Radar (GPR) data from terrestrial analog environments can help constrain models for evolution of the lunar surface, aid in interpretation of orbital SAR data, and help predict what might be encountered in the subsurface during future, landed, scientific or engineering operations on the Moon. GPR can yield insight into the physical properties, clast-size distribution, and layering of the subsurface, granting a unique view of the processes affecting an area over geologic time. The purpose of our work is to demonstrate these capabilities at sites at which geologic processes, settings, and/or materials are similar to those that may be encountered on the moon, especially lava flows, impact-crater ejecta, and layered materials with varying properties. We present results from transects obtained at Barringer Meteor Crater, SP Volcano cinder cone, and Sunset Crater Volcano National Monument, all in northern Arizona. Transects were taken at several sites on the ejecta of Meteor Crater, all within a crater radius (~400 m) of the crater rim. Those taken across ejecta lobes or mounds reveal the subsurface contact of the ejecta upper surface and overlying, embaying sediments deposited by later alluvial, colluvial, and/or aeolian processes. Existing mine shafts and pits on the south side of the crater provide cross sections of the subsurface against which we compare adjacent GPR transects. The ‘actual’ number, size, and depth of clasts in the top 1-2 m of the subsurface are estimated from photos of the exposed cross sections. In GPR radargrams, reflections attributed to blocks in the top 2-5 m of the subsurface are counted, and their depth distribution noted. Taking GPR measurements along a transect at two frequencies (200 and 400 MHz) and to various depths, we obtain the ratio of the actual number of blocks in the subsurface to the number detectable with GPR, as well as an assessment of how GPR detections in ejecta decline with depth and depend on antenna

  10. Bedrock and surficial geologic map of the Satan Butte and Greasewood 7.5’ quadrangles, Navajo and Apache Counties, northern Arizona

    Science.gov (United States)

    Amoroso, Lee; Priest, Susan S.; Hiza-Redsteer, Margaret

    2013-01-01

    The geologic map of the Satan Butte and Greasewood 7.5’ quadrangles is the result of a cooperative effort of the U.S. Geological Survey (USGS) and the Navajo Nation to provide regional geologic information for management and planning officials. This map provides geologic information useful for range management, plant and animal studies, flood control, water resource investigations, and natural hazards associated with sand-dune mobility. The map provides connectivity to the regional geologic framework of the Grand Canyon area of northern Arizona. The map area encompasses approximately 314 km2 (123 mi2) within Navajo and Apache Counties of northern Arizona and is bounded by lat 35°37'30" to 35°30' N., long 109°45' to 110° W. The quadrangles lie within the southern Colorado Plateau geologic province and within the northeastern portion of the Hopi Buttes (Tsézhin Bií). Large ephemeral drainages, Pueblo Colorado Wash and Steamboat Wash, originate north of the map area on the Defiance Plateau and Balakai Mesa respectively. Elevations range from 1,930 m (6,330 ft) at the top of Satan Butte to about 1,787 m (5,860 ft) at Pueblo Colorado Wash where it exits the southwest corner of the Greasewood quadrangle. The only settlement within the map area is Greasewood, Arizona, on the north side of Pueblo Colorado Wash. Navajo Highway 15 crosses both quadrangles and joins State Highway 264 northwest of Ganado. Unimproved dirt roads provide access to remote parts of the Navajo Reservation.

  11. Influence of elevation on bark beetle (Coleoptera: Curculionidae, Scolytinae) community structure and flight periodicity in ponderosa pine forests of Arizona.

    Science.gov (United States)

    Williams, Kelly K; McMillin, Joel D; DeGomez, Tom E; Clancy, Karen M; Miller, Andy

    2008-02-01

    We examined abundance and flight periodicity of five Ips and six Dendroctonus species (Coleoptera: Curculionidae, Scolytinae) among three different elevation bands in ponderosa pine (Pinus ponderosa Douglas ex. Lawson) forests of northcentral Arizona. Bark beetle populations were monitored at 10 sites in each of three elevation bands (low: 1,600-1,736 m; middle: 2,058-2,230 m; high: 2,505-2,651 m) for 3 yr (2004-2006) using pheromone-baited Lindgren funnel traps. Trap contents were collected weekly from March to December. We also studied temperature differences among the elevation bands and what role this may play in beetle flight behavior. Bark beetles, regardless of species, showed no consistent elevational trend in abundance among the three bands. The higher abundances of Ips lecontei Swaine, I. calligraphus ponderosae Swaine, Dendroctonus frontalis Zimmerman, and D. brevicomis LeConte at low and middle elevations offset the greater abundance of I. knausi Swaine, D. adjunctus Blandford, D. approximatus Dietz, and D. valens LeConte at high elevations. I. pini (Say) and I. latidens LeConte were found in similar numbers across the three bands. Flight periodicity of several species varied among elevation bands. In general, the flight period shortened as elevation increased; flight initiated later and terminated earlier in the year. The timing, number, and magnitude of peaks in flight activity also varied among the elevation bands. These results suggest that abundance and flight seasonality of several bark beetles are related to elevation and the associated temperature differences. The implications of these results are discussed in relation to bark beetle management and population dynamics.

  12. Assessing the sustainability of forest management: an application of multi-criteria decision analysis to community forests in northern Ethiopia.

    Science.gov (United States)

    Balana, Bedru Babulo; Mathijs, Erik; Muys, Bart

    2010-06-01

    Continuous deterioration of the natural resource base has become a serious threat to both the ecological systems and economic production in Ethiopia. Many of these problems have been attributed directly or indirectly to the rapid dwindling of the country's forest cover which is associated with unsustainable forest use and management. Closing community woodlands from human and livestock intervention to promote natural regeneration of forests has been one of the environmental restoration strategies pursued in the degraded highland areas of northern Ethiopia. However, local pressure to use reforested community lands for economic benefit has become a major threat to forest sustainability. Using locally identified sets of criteria and indicators for sustainable community forest management, this paper applies a multi-criteria decision analysis tool to evaluate forest management problems in the northern province of Tigray, Ethiopia. Three MCA methods - ranking, pair-wise comparison, and scoring - were used in evaluating the sets of criteria and indicators and alternative forest management scenarios. Results from the study indicate a number of noteworthy points: 1) MCA techniques both for identifying local level sustainability criteria and indicators and evaluating management schemes in a participatory decision environment appear to be effective tools to address local resource management problems; 2) Evaluated against the selected sets of criteria and indicators, the current forest management regime in the study area is not on a sustainable path; 3) Acquainting local people with adequate environmental knowledge and raising local awareness about the long-term consequences of environmental degradation ranked first among the set of sustainability criteria; and 4) In order to harmonize both environmental and economic objectives, the present 'ecological-biased' forest management regime needs to be substituted by an appropriate holistic scheme that takes into account

  13. Multi-season climate synchronized forest fires throughout the 20th century, Northern Rockies, USA

    Science.gov (United States)

    Penelope Morgan; Emily K. Heyerdahl; Carly E. Gibson

    2008-01-01

    We inferred climate drivers of 20th-century years with regionally synchronous forest fires in the U.S. northern Rockies. We derived annual fire extent from an existing fire atlas that includes 5038 fire polygons recorded from 12 070 086 ha, or 71% of the forested land in Idaho and Montana west of the Continental Divide. The 11 regional-fire years, those exceeding the...

  14. Significant and persistent impact of timber harvesting on soil microbial communities in Northern coniferous forests.

    Science.gov (United States)

    Hartmann, Martin; Howes, Charles G; VanInsberghe, David; Yu, Hang; Bachar, Dipankar; Christen, Richard; Henrik Nilsson, Rolf; Hallam, Steven J; Mohn, William W

    2012-12-01

    Forest ecosystems have integral roles in climate stability, biodiversity and economic development. Soil stewardship is essential for sustainable forest management. Organic matter (OM) removal and soil compaction are key disturbances associated with forest harvesting, but their impacts on forest ecosystems are not well understood. Because microbiological processes regulate soil ecology and biogeochemistry, microbial community structure might serve as indicator of forest ecosystem status, revealing changes in nutrient and energy flow patterns before they have irreversible effects on long-term soil productivity. We applied massively parallel pyrosequencing of over 4.6 million ribosomal marker sequences to assess the impact of OM removal and soil compaction on bacterial and fungal communities in a field experiment replicated at six forest sites in British Columbia, Canada. More than a decade after harvesting, diversity and structure of soil bacterial and fungal communities remained significantly altered by harvesting disturbances, with individual taxonomic groups responding differentially to varied levels of the disturbances. Plant symbionts, like ectomycorrhizal fungi, and saprobic taxa, such as ascomycetes and actinomycetes, were among the most sensitive to harvesting disturbances. Given their significant ecological roles in forest development, the fate of these taxa might be critical for sustainability of forest ecosystems. Although abundant bacterial populations were ubiquitous, abundant fungal populations often revealed a patchy distribution, consistent with their higher sensitivity to the examined soil disturbances. These results establish a comprehensive inventory of bacterial and fungal community composition in northern coniferous forests and demonstrate the long-term response of their structure to key disturbances associated with forest harvesting.

  15. Integrated effects of air pollution and climate change on forests: a northern hemisphere perspective.

    Science.gov (United States)

    Bytnerowicz, Andrzej; Omasa, Kenji; Paoletti, Elena

    2007-06-01

    Many air pollutants and greenhouse gases have common sources, contribute to radiative balance, interact in the atmosphere, and affect ecosystems. The impacts on forest ecosystems have been traditionally treated separately for air pollution and climate change. However, the combined effects may significantly differ from a sum of separate effects. We review the links between air pollution and climate change and their interactive effects on northern hemisphere forests. A simultaneous addressing of the air pollution and climate change effects on forests may result in more effective research, management and monitoring as well as better integration of local, national and global environmental policies.

  16. The carbon holdings of northern Ecuador's mangrove forests

    CERN Document Server

    Hamilton, Stuart E; Borbor, Mercy; Millones, Marco

    2016-01-01

    Within a GIS environment, we combine field measures of mangrove diameter, mangrove species distribution, and mangrove density with remotely sensed measures of mangrove location and mangrove canopy cover to estimate the mangrove carbon holdings of northern Ecuador. We find that the four northern estuaries of Ecuador contain approximately 7,742,999 t (plus or minus 15.47 percent) of standing carbon. Of particular high carbon holdings are the Rhizophora mangle dominated mangrove stands found in-and-around the Cayapas-Mataje Ecological Reserve in northern Esmeraldas Province, Ecuador and certain stands of Rhizophora mangle in-and-around the Isla Corazon y Fragata Wildlife Refuge in central Manabi Province, Ecuador. Our field driven mangrove carbon estimate is higher than all but one of the comparison models evaluated. We find that basic latitudinal mangrove carbon models performed at least as well, if not better, than the more complex species based allometric models in predicting standing carbon levels. In additi...

  17. Dynamics of carbon storage in the woody biomass of northern forests

    Science.gov (United States)

    Dong, Jiarui

    2002-09-01

    Part of the puzzle of greenhouse gases and climate change is determining where carbon dioxide (CO2) is absorbed, and what causes a region to become a "carbon sink". Analyses of atmospheric CO2 concentration changes indicate a carbon sink of about 1 to 2 billion tons on land in the northerly regions. Elsewhere the land is suggested to be neutral, which implies that emissions of another 1.5 billion tons of carbon a year from cutting and burning of tropical forests are nearly balanced by sinks of similar magnitude there. The geographical detail of the land carbon sink has, however, remained elusive. Forest greenness observations from sensors on National Oceanic and Atmospheric Administration satellites were combined with wood volume data from forest inventories to produce relatively high resolution maps of carbon stocks in about 15 million square kilometers of northern forests, roughly above the 30th parallel. Comparison of carbon stock maps from the late 1990s and early 1980s identifies where forests were storing carbon and where they were losing carbon. Results indicate that about 61 billion tons of carbon is contained in the wood of these northern forests. Further, the analysis indicates that forests in Europe, Russia and America have been storing nearly 700 million metric tons of carbon a year, or about 12% of annual global carbon emissions from industrial activities, during the 1980s and 1990s. American forests absorbed 120 million tons of carbon a year, which is about 11% of the USA's annual emissions. With the exception of some Canadian boreal forests, which were found to be losing carbon, most northern forests were storing carbon. Russia, the country with the most forests, accounted for almost 40 percent of the biomass carbon sink. This study has important scientific, economic and policy implications. The scientific implication is that it deconstructs the mystery of the land carbon sink by providing geographically detailed maps of forest carbon pools, sources

  18. Limber pine forests on the leading edge of white pine blister rust distribution in Northern Colorado

    Science.gov (United States)

    Jennifer G. Klutsch; Betsy A. Goodrich; Anna W. Schoettle

    2011-01-01

    The combined threats of the current mountain pine beetle (Dendroctonus ponderosae, MPB) epidemic with the imminent invasion of white pine blister rust (caused by the non-native fungus Cronartium ribicola, WPBR) in limber pine (Pinus flexilis) forests in northern Colorado threatens the limber pine's regeneration cycle and ecosystem function. Over one million...

  19. Effects of canopy herbivory on nutrient cycling in a northern hardwood forest in Western North Carolina

    Science.gov (United States)

    Barbara C. Reynolds; Mark D. Hunter; D.A. Crossely

    2000-01-01

    In May 1998 an outbreak of sawflies, Periclista sp. (Hymenoptera: Symphyta), occurred in a high-elevation hardwood forest in western North Carolina. Estimated defoliation of northern red oak (Quercus rubra) and white oak (Q. alba) removed 40% of leaf area Weights of frass (insect feces) collected at the site...

  20. Effects of even-aged management on forest birds at northern hardwood stand interfaces

    Science.gov (United States)

    Richard M. DeGraaf

    1992-01-01

    Breeding birds were counted along transects across edges of even-aged northern hardwood stands in the White Mountain National Forest, New Hampshire, U.S.A. Two replicate transects across each of 7 edge types representing 3 classes of contrast (abrupt, intermediate, and subtle) were sampled during June 1983-1985 to define species assemblages at stand edges and estimate...

  1. Age-dependent changes in ecosystem carbon fluxes in managed forests in Northern Wisconsin, USA

    Science.gov (United States)

    Asko Noormets; Jiquan Chen; Thomas R. Crow

    2007-01-01

    The age-dependent variability of ecosystem carbon (C) fluxes was assessed by measuring the net ecosystem exchange of C (NEE) in five managed forest stands in northern Wisconsin, USA. The study sites ranged in age from 3-year-old clearcut to mature stands (65 years). All stands, except the clearcut, accumulated C over the study period from May to October 2002. Seasonal...

  2. Multi-season climate synchronized historical fires in dry forests (1650-1900), Northern Rockies, USA

    Science.gov (United States)

    Emily K. Heyerdahl; Penelope Morgan; James P. Riser

    2008-01-01

    Our objective was to infer the climate drivers of regionally synchronous fire years in dry forests of the U.S. northern Rockies in Idaho and western Montana. During our analysis period (1650-­1900), we reconstructed fires from 9245 fire scars on 576 trees (mostly ponderosa pine, Pinus ponderosa P. & C. Lawson) at 21 sites and compared them to...

  3. Pollen rain and pollen representation across a forest-páramo ecotone in northern Ecuador

    NARCIS (Netherlands)

    Moscol Olivera, M.; Duivenvoorden, J.F.; Hooghiemstra, H.

    2009-01-01

    Modern pollen spectra were studied in forest and páramo vegetation from the Guandera area, northern Ecuador. Pollen representation was estimated by comparing the presence of plant taxa from a recent vegetation survey with the pollen spectra in moss polsters and pollen traps. In total, 73 pollen taxa

  4. Pollen rain and pollen representation across a forest-páramo ecotone in northern Ecuador

    NARCIS (Netherlands)

    Moscol Olivera, M.; Duivenvoorden, J.F.; Hooghiemstra, H.

    2009-01-01

    Modern pollen spectra were studied in forest and páramo vegetation from the Guandera area, northern Ecuador. Pollen representation was estimated by comparing the presence of plant taxa from a recent vegetation survey with the pollen spectra in moss polsters and pollen traps. In total, 73 pollen taxa

  5. Behavioral modifications in northern bearded saki monkeys (Chiropotes satanas chiropotes) in forest fragments of central Amazonia.

    Science.gov (United States)

    Boyle, Sarah Ann; Smith, Andrew T

    2010-01-01

    We investigated behavioral differences among seven groups of northern bearded saki monkeys (Chiropotes satanas chiropotes) living in five forest fragments and two areas of continuous forest at the Biological Dynamics of Forest Fragments Project study area, located approximately 80 km north of Manaus, Brazil. We collected data in six research cycles from July-August 2003 to January 2005-April 2006. When bearded saki monkeys were present in a study area, we followed the group from dawn until dusk for three consecutive days. Every 5 min, we conducted behavioral scans of all visible individuals. There was a positive relationship between forest size and group size, but animals in the small forest fragments lived at greater densities. Bearded saki monkeys in the smaller fragments spent more time resting, less time traveling, and less time vocalizing, but there was no relationship between forest size and the amount of time spent feeding. Our results indicate that the main behavioral differences among the groups are related to the amount of forest resources (e.g., fruit trees, space) available to the monkeys in the smaller fragments, as well as the resulting smaller group sizes. We stress the need to preserve large tracts of forest and provide connectivity between forest patches.

  6. Soil moisture patterns in a northern coniferous forest

    Science.gov (United States)

    Thomas F. McLintock

    1959-01-01

    The trend of soil moisture during the growing season, the alternate wetting from rainfall and drying during clear weather, determines the amount of moisture available for tree growth and also fixes, in part, the environment for root growth. In much of the northern coniferous region both moisture content and root environment are in turn affected by the hummock-and-...

  7. Taxonomic Diversity of Lianas in Tropical Forests of Northern Eastern Ghats of Andhra Pradesh, India

    Directory of Open Access Journals (Sweden)

    Maradana TARAKESWARA NAIDU

    2014-03-01

    Full Text Available Lianas are important in forest ecosystem and strongly influence the forest dynamics and diversity. Lianas are common in the tropical moist deciduous and rain forests, which are competing with other forest trees. Little information is known on the habitat specialization in tropical lianas diversity and the root causes for variation among forests in liana species composition. A total of 170 liana species (≥ 1.5 cm girth at breast height representing 109 genera and 43 families were reported in 5×5 m quadrate samples along with their climbing modes in the tropical forests of northern Eastern Ghats of Andhra Pradesh, India. A total of 210 grids were sampled in study area and reported that Convolvulaceae was the dominant family with 23 species followed by Papilionaceae, 22 species and Asclepiadaceae, 19 species and Ipomoea was the largest genera. Woody lianas were dominated by 128 species and these are classified into six climbing modes consisting in stem climbers (53.5% that were the most predominant followed by stragglersunarmed (14.7%, stragglers armed and tendril climbers (13.5% each, root climbers (2.9% and hook climbers (1.8%. The most dominant liana species in the northern Eastern Ghats were Acacia sinuata and Bauhinia vahlii. The results of this investigation suggests that better management and protection is an important for in situ conservation of liana diversity and involving local people is emphasized.

  8. Assessing the Sensitivity of Mountain Forests to Site Degradation in the Northern Limestone Alps, Europe

    Directory of Open Access Journals (Sweden)

    Birgit Reger

    2015-05-01

    Full Text Available Because of some land-use practices (such as overstocking with wild ungulates, historical clear-cuts for mining, and locally persisting forest pasture, protective forests in the montane vegetation belt of the Northern Limestone Alps are now frequently overaged and poorly structured over large areas. Windthrow and bark beetle infestations have generated disturbance areas in which forests have lost their protective functions. Where unfavorable site conditions hamper regeneration for decades, severe soil loss may ensue. To help prioritize management interventions, we developed a geographic information system-based model for assessing sensitivity to site degradation and applied it to 4 test areas in the Northern Limestone Alps of Austria and Bavaria. The model consists of (1 analysis of site conditions and forest stand structures that could increase sensitivity to degradation, (2 evaluation of the sensitivity of sites and stands, and (3 evaluation and mapping of mountain forests' sensitivity to degradation. Site conditions were modeled using regression algorithms with data on site parameters from pointwise soil and vegetation surveys as responses and areawide geodata on climate, relief, and substrate as predictors. The resulting predictor–response relationships were applied to test areas. Stand structure was detected from airborne laser scanning data. Site and stand parameters were evaluated according to their sensitivity to site degradation. Sensitivities of sites and stands were summarized in intermediate-scale sensitivity maps. High sensitivity was identified in 3 test areas with pure limestone and dolomite as the prevailing sensitivity level. Moderately sensitive forests dominate in the final test area, Grünstein, where the bedrock in some strata contains larger amounts of siliceous components (marl, mudstone, and moraines; degraded and slightly sensitive forests were rare or nonexistent in all 4 test areas. Providing a comprehensive overview

  9. Effects of human subsistence activities on forest birds in northern Kenya.

    Science.gov (United States)

    Borghesio, Luca

    2008-04-01

    Indigenous tribes and conservation biologists may have common goals and may be able to collaborate on the maintenance of biodiversity, but few researchers have evaluated the impacts and potential benefits of human subsistence activities. I studied the effects of subsistence activities (primarily wood collection) of nomadic pastoralists in 3 Afromontane forests of northern Kenya. In surveys of 404, 25-m-radius plots, I recorded vegetation structure and composition of the forest bird community. Plots with higher levels of human activity had significantly different vegetation structure, with more-open canopies, more grass, and fewer tree stems. Nectarivores (abundance +231%) and aerial insectivores (+66%) were more abundant in plots with more-intense wood collecting than in plots with less human activity, whereas abundance of forest specialists (-28%) decreased in plots with more-intense human activity. Abundance of 58% of the bird species either increased or decreased significantly in plots with more-intense human activity. Generally, the number of individuals of forest specialists decreased (6 of 7 species showed significant responses) and the number of individuals of edge and nonforest species increased with increasing human activity. Canonical correspondence analysis showed that an intensification of human activities would favor nectarivores, aerial insectivores, granivores, and omnivores and would negatively affect large-sized, ground-foraging species and arboreal frugivores. Subsistence human activities favored the invasion of forest by edge species at the expense of forest specialists; thus, further intensification of forest exploitation by local peoples is not recommended. At the same time, however, subsistence activities in northern Kenya forests appeared to increase the structural diversity of the vegetation and provided suitable habitat for part (but not all) of the forest avifauna, which suggests that subsistence human activities may have a role in the

  10. Fire Return Interval Within the Northern Boundary of the Larch Forest

    Science.gov (United States)

    Kharuk, V. I.; Dvinskaya, M. L.; Ranson, K. J.

    2011-01-01

    Larch (Larix spp.) dominant forests compose a large proportion of the forests of Russia (i.e., about 40% of forested areas). These forests range from the Yenisei ridge on the west to the Pacific Ocean on the east, and from Lake Baikal on the south to the 73rd parallel in the north. Larch stands comprise the world s northern most forest at Ary-Mas (72 deg 28' N, 102 deg 15' E). Larch dominated forests occupy about 70% of the permafrost areas in Siberia. Larch forms high closure stands as well as open forests, and is found mainly over permafrost, where other tree species barely survive. Wildfires are typical for this territory with the majority occurring as ground fires due to low crown closure. Due to the thin active layer in permafrost soils and a dense lichen-moss cover, ground fires may cause stand mortality. The vast areas of larch-dominant forests is generally considered as a "carbon sink"; however, positive long-term temperature trends at higher latitudes are expected to result in an increase of fire frequency, and thus may convert this area to a source for greenhouse gases. There are recent observations regarding the increase of fire frequency within non-protected territories. Surprisingly, there are few publications on fire chronoseqences for the huge forested territory between the Ural Mountains and the Pacific Ocean. Also there is a general understanding that bimodal (late spring -- early summer and late summer-beginning of fall) fire seasonal distribution in the south becomes uni-modal (late spring -- early summer) in the north. The purpose of this study is to investigate the wildfire history at the northern edge of the zone of larch dominance.

  11. Nitrogen balance along a northern boreal forest fire chronosequence.

    Science.gov (United States)

    Palviainen, Marjo; Pumpanen, Jukka; Berninger, Frank; Ritala, Kaisa; Duan, Baoli; Heinonsalo, Jussi; Sun, Hui; Köster, Egle; Köster, Kajar

    2017-01-01

    Fire is a major natural disturbance factor in boreal forests, and the frequency of forest fires is predicted to increase due to climate change. Nitrogen (N) is a key determinant of carbon sequestration in boreal forests because the shortage of N limits tree growth. We studied changes in N pools and fluxes, and the overall N balance across a 155-year non stand-replacing fire chronosequence in sub-arctic Pinus sylvestris forests in Finland. Two years after the fire, total ecosystem N pool was 622 kg ha-1 of which 16% was in the vegetation, 8% in the dead biomass and 76% in the soil. 155 years after the fire, total N pool was 960 kg ha-1, with 27% in the vegetation, 3% in the dead biomass and 69% in the soil. This implies an annual accumulation rate of 2.28 kg ha-1 which was distributed equally between soil and biomass. The observed changes in N pools were consistent with the computed N balance +2.11 kg ha-1 yr-1 over the 155-year post-fire period. Nitrogen deposition was an important component of the N balance. The biological N fixation increased with succession and constituted 9% of the total N input during the 155 post-fire years. N2O fluxes were negligible (≤ 0.01 kg ha-1 yr-1) and did not differ among post-fire age classes. The number and intensity of microbial genes involved in N cycling were lower at the site 60 years after fire compared to the youngest and the oldest sites indicating potential differences in soil N cycling processes. The results suggest that in sub-arctic pine forests, the non-stand-replacing, intermediate-severity fires decrease considerably N pools in biomass but changes in soil and total ecosystem N pools are slight. Current fire-return interval does not seem to pose a great threat to ecosystem productivity and N status in these sub-arctic forests.

  12. Plants Species Diversity in Hyrcanian Hardwood Forests, Northern Iran (Case Study: Mazandaran Province

    Directory of Open Access Journals (Sweden)

    Kambiz Abrari Vajari

    2013-12-01

    Full Text Available In order to better understand and manage forest ecosystems, it is important to study the relationship between environmental factors and plants in these ecosystems. We investigated plant species diversity of three hardwood forest stands in the Hyrcanian forests, Sari, northern Iran. Our aim was to determine the effect of forest stand type on the diversity of plant species. One plot 150 × 150 m established at the center of each forest stand and in each plot, nine subplots 50 × 50 m were selected. Diversity values (Richness, diversity and evenness indices were measured in five sample areas 0.01 ha per 50 × 50 m quadrates by estimating cover percentage of each species. The results showed that Geophytes (43.33% had the highest life form spectrum among species. JACCARD'S similarity index revealed that the highest values exist between Parrotia-Carpinus and Carpinus stands. All herb layer species diversity indices varied significantly among different forest stands. Cover percentage significantly positively correlated with diversity indices in Parrotia-Carpinus stand. Diversity and richness indices of herb-layers plants were significantly negatively correlated with cover percentage in Fagus stand. Correlation analysis between all diversity measures and cover percentage in Carpinus stand wasn't significant. The result of the present study revealed that species diversity in temperate broad-leaved deciduous forest was significantly influenced by forest stand type

  13. Liana habitat and host preferences in northern temperate forests

    Science.gov (United States)

    Leicht-Young, S. A.; Pavlovic, N.B.; Frohnapple, K.J.; Grundel, R.

    2010-01-01

    Lianas and other climbers are important ecological and structural components of forest communities. Like other plants, their abundance in a given habitat depends on a variety of factors, such as light, soil moisture and nutrients. However, since lianas require external support, host tree characteristics also influence their distribution. Lianas are conspicuous life forms in tropical regions, but in temperate areas, where they are less prominent, little is known about factors that control their distributions in these forests. We surveyed the climbing plant species in 20 mature (100 years and greater) forested habitats in the Midwest USA at a variety of levels from simple presence/absence, to ground layer abundances, to those species that had ascended trees. We also examined attributes of the tree species with climbers attached to them. Using cluster analysis, we distinguished five different tree communities in our survey locations. We determined that 25% of the trees we surveyed had one or more lianas attached to it, with Parthenocissus quinquefolia (Virginia creeper) the most common climbing species encountered. Canopy cover and soil attributes both influenced climber species presence/absence and ground layer climber abundance. The proportion of liana species of a given climbing type (roots, stem twiner, tendril climber) was significantly related to the DBH of the host tree, with more root climbers and fewer stem and tendril climbers on large trees. In general, the DBH of climbing lianas had a significant positive relationship to the DBH of the host tree; however this varied by the identity of the liana and the tree species. The greater the DBH of the host tree, the higher the probability that it was colonized by one or more lianas, with tree species such as Pinus banksiana (jack pine) and Quercus alba (white oak) being more susceptible to liana colonization than others. Finally, some liana species such as Celastrus scandens (American bittersweet) showed a

  14. The role of temperature and temperature-induced drought on forest productivity in the Northern Countries

    Science.gov (United States)

    Ruiz Pérez, Guiomar; Vico, Giulia

    2017-04-01

    Forests play an important role in the climate system and the global carbon cycle and is of considerable socioeconomic importance for Northern countries. For example, Sweden has pursued more intensive forest harvesting as a way of fulfilling the requirements of the EU renewable energy directive. Due to ecological and economical role of forests, it is imperative to better understand the physical and biological processes leading to potential changes in productivity. There is no consensus regarding the net effect of raising temperatures on vegetation productivity in this area. There exist the idea that in response to warmer temperatures, forests located in cold regions may benefit from longer growing seasons and, consequently, become more productive. However, radial growth and wood density measurements suggest that in recent decades, there has been a "divergence" between warming and tree growth, with localized shifts to a negative relationship between temperature and growth. This unexpected adverse response of forests in northern areas under warming is consistent with the fact that they are becoming more vulnerable to warm-related disturbances including temperature-induced drought stress. Here we focus on satellite NDVI record as an indicator of greenness vegetation across the Northern Countries for the period 2000 to present and explore corresponding relationships with high-resolution gridded climate data from E-OBS. By focusing on the whole Sweden, we were able to assess whether the role played by each climatic driver (precipitation, temperature and a dryness index) differed in different locations. In particular, a Partial Least Square (PLS) regression analysis was conducted to investigate the model component structure among the potential drivers explaining the annual variations of the mean NDVI observed during the growing season. We observed how forests respond differently to climatic drivers and their extremes when the increasing temperature occurs together with

  15. Changes in faunal and vegetation communities along a soil calcium gradient in northern hardwood forests

    Science.gov (United States)

    Beier, Colin M.; Woods, Anne M.; Hotopp, Kenneth P.; Gibbs, James P.; Mitchell, Myron J.; Dovciak, Martin; Leopold, Donald J.; Lawrence, Gregory B.; Page, Blair D.

    2012-01-01

    Depletion of Ca from forest soils due to acidic deposition has had potentially pervasive effects on forest communities, but these impacts remain largely unknown. Because snails, salamanders, and plants play essential roles in the Ca cycle of northern hardwood forests, we hypothesized that their community diversity, abundance, and structure would vary with differences in biotic Ca availability. To test this hypothesis, we sampled 12 upland hardwood forests representing a soil Ca gradient in the Adirondack Mountains, New York (USA), where chronic deposition has resulted in acidified soils but where areas of well-buffered soils remain Ca rich due to parent materials. Along the gradient of increasing soil [Ca2+], we observed increasing trends in snail community richness and abundance, live biomass of redback salamanders (Plethodon cinereus (Green, 1818)), and canopy tree basal area. Salamander communities were dominated by mountain dusky salamanders (Desmognathus ochrophaeus Cope, 1859) at Ca-poor sites and changed continuously along the Ca gradient to become dominated by redback salamanders at the Ca-rich sites. Several known calciphilic species of snails and plants were found only at the highest-Ca sites. Our results indicated that Ca availability, which is shaped by geology and acidic deposition inputs, influences northern hardwood forest ecosystems at multiple trophic levels, although the underlying mechanisms require further study.

  16. Taper functions and merchantable timber for temperate forests of northern Mexico

    Directory of Open Access Journals (Sweden)

    José Návar

    2013-05-01

    Full Text Available Taper functions are required in modern forest management in estimationof the end forest products, to be classified for their life time in the environment. Based on a sample of 1640 trees of 10 species measured in volume, biomass and taper project on Mexico’s northern temperate, mixed, uneven-aged coniferous forests, 12 stem profile taper functions were fitted in order to select the equation that provides better diameter estimates at commercial tree height. Although several equations fitted better specific tree species, the Newnham (1990 equation consistently yielded better diameter estimates at any length of the stem for all studied species. The confidence intervals on the Newnham (1990 equation parameters showed that each species has an unique stem profile and, therefore, single parameter equations are reported. Because of lack of analytical integration, the recommendedtaper equation (when numerically integrated provided compatible,unbiased total bole volume when contrasted to conventional timber volume assessments. Data for 637 circular, 1/10 ha, plots from temperate forests of Central Durango, Mexico estimated a mean of 135 m3 ha-1, of which 18, 59, 30, and 17 m3 ha-1 could be classified as poles, sawn wood, plywood and secondary forest products, respectively. This information can be used for the planning of the forest industry to optimize forest products derived from timber harvesting, as well as for estimating other environmental components.

  17. Taper functions and merchantable timber for temperate forests of northern Mexico

    Directory of Open Access Journals (Sweden)

    José Návar

    2013-07-01

    Full Text Available Taper functions are required in modern forest management in estimation of the end forest products, to be classified for their life time in the environment. Based on a sample of 1640 trees of 10 species measured in volume, biomass and taper project on Mexico’s northern temperate, mixed, uneven-aged coniferous forests, 12 stem profile taper functions were fitted in order to select the equation that provides better diameter estimates at commercial tree height. Although several equations fitted better specific tree species, the Newnham (1990 equation consistently yielded better diameter estimates at any length of the stem for all studied species. The confidence intervals on the Newnham (1990 equation parameters showed that each species has an unique stem profile and, therefore, single parameter equations are reported. Because of lack of analytical integration, the recommended taper equation (when numerically integrated provided compatible, unbiased total bole volume when contrasted to conventional timber volume assessments. Data for 637 circular, 1/10 ha, plots from temperate forests of Central Durango, Mexico estimated a mean of 135 m3 ha-1, of which 18, 59, 30, and 17 m3 ha-1 could be classified as poles, sawn wood, plywood and secondary forest products, respectively. This information can be used for the planning of the forest industry to optimize forest products derived from timber harvesting, as well as for estimating other environmental components. 

  18. Ecology of cultivable yeasts in pristine forests in northern Patagonia (Argentina) influenced by different environmental factors.

    Science.gov (United States)

    Mestre, María Cecilia; Fontenla, Sonia; Rosa, Carlos A

    2014-06-01

    Environmental factors influencing the occurrence and community structure of soil yeasts in forests are not well studied. There are few studies dedicated to Southern Hemisphere soil yeasts populations and even fewer focused on temperate forests influenced by volcanic activity. The present work aimed to study the ecology of soil yeast communities from pristine forests influenced by different environmental factors (precipitation, physicochemical properties of soil, tree species, soil region, and season). The survey was performed in 4 northern Patagonian forests: 2 dominated by Nothofagus pumilio and 2 by Nothofagus antarctica. Yeast communities were described with ecological indices and species accumulation curves, and their association with environmental characteristics was assessed using multivariate analysis. Each forest site showed a particular arrangement of species as a result of environmental characteristics, such as dominant plant species, nutrient availability, and climatic characteristics. Cryptococcus podzolicus was most frequently isolated in nutrient-rich soils, Trichosporon porosum dominated cold mountain forests with low nutrient and water availability in soil, and capsulated yeasts such as Cryptococcus phenolicus dominated forest sites with low precipitation. The present work suggests that environmental factors affecting yeast communities may not be the current soil characteristics but the result of complex interactions of factors including natural disturbances like volcanic activity.

  19. Photo series for quantifying forest fuels in Mexico: montane subtropical forests of the Sierra Madre del Sur and temperate forests and montane shrubland of the northern Sierra Madre Oriental

    Science.gov (United States)

    Jorge E. Morfin-Rios; Ernesto Alvarado-Celestino; Enrique J. Jardel-Pelaez; Robert E. Vihnanek; David K. Wright; Jose M. Michel-Fuentes; Clinton S. Wright; Roger D. Ottmar; David V. Sandberg; Andres Najera-Diaz

    2008-01-01

    Single wide-angle and stereo photographs display a range of forest ecosystems conditions and fuel loadings in montane subtropical forests of the Sierra Madre del Sur and temperate forests and montane shrubland of the northern Sierra Madre Oriental of Mexico. Each group of photographs includes inventory information summarizing overstory vegetation composition and...

  20. Zonobiomes, forests, and major forest-forming conifers across Northern Eurasia by the end of the century under climate warming

    Science.gov (United States)

    Tchebakova, N.; Parfenova, E. I.; Shvetsov, E.; Soja, A. J.; Conard, S. G.

    2012-12-01

    Simulations of terrestrial ecosystems demonstrated globally the profound effects of the GCM-predicted climate change on their distribution at all hierarchical levels: zonobiomes, forests, and forest-forming tree species. We investigated progressions of potential vegetation cover, forest cover and ranges of forest-forming conifers across Northern Eurasia and Russia in the warming climate during the current century. We developed envelope-type static large-scale bioclimatic models predicting zonobiomes NEBioCliM, forests (ForCliM) and primary forest-forming conifer trees (TreeCliM)) from three bioclimatic indices (1) growing degree-days above 5oC, GDD5; (2) negative degree-days below 0oC, NDDo; and (3) an annual moisture index (ratio of growing degree days above 5oC to annual precipitation), AMI. No soil conditions except presence/absence of permafrost were taken into account in our models. Continuous permafrost was included in the models as limiting the forests and tree species distribution in interior Siberia. Each zonobiome, forest type and conifer distribution was mapped for the basic period 1960-1990 and for 2080 by coupling our bioclimatic models with bioclimatic indices and the permafrost distribution for the 1960-1990 and 2080 simulations. Climatic departures for the 2080 climate were derived from two climate change scenarios, the HadCM3 A2 and B1 (IPCC, 2007). Kappa (K) statistics were used to compare both the modeled vegetation and the conifer distributions in the contemporary climate to actual vegetation and forest maps. K-statistics proved that NEBioCliM accomplished a fair work in modeling zonobiomes across Russia. The tree species distributions also showed good match with the modeled ranges: 41% (Abies sibirica), 46% (Pinus sibirica), 71% (Pinus sylvestris), 75% (Picea spp.) and 78% (Larix spp.). Those matches might be higher because historically part of the primary conifer forests were replaced by secondary birch and aspen forests after large

  1. Demography of northern flying squirrels informs ecosystem management of western interior forests.

    Science.gov (United States)

    Lehmkuhl, John F; Kistler, Keith D; Begley, James S; Boulanger, John

    2006-04-01

    We studied northern flying squirrel (Glaucomys sabrinus) demography in the eastern Washington Cascade Range to test hypotheses about regional and local abundance patterns and to inform managers of the possible effects of fire and fuels management on flying squirrels. We quantified habitat characteristics and squirrel density, population trends, and demography in three typical forest cover types over a four-year period. We had 2034 captures of flying squirrels over 41 000 trap nights from 1997 through 2000 and marked 879 squirrels for mark-recapture population analysis. Ponderosa pine (Pinus ponderosa) forest appeared to be poorer habitat for flying squirrels than young or mature mixed-conifer forest. About 35% fewer individuals were captured in open pine forest than in dry mixed-conifer Douglas-fir (Pseudotsuga menziesii) and grand fir (Abies grandis) forests. Home ranges were 85% larger in pine forest (4.6 ha) than in mixed-conifer forests (2.5 ha). Similarly, population density (Huggins estimator) in ponderosa pine forest was half (1.1 squirrels/ha) that of mixed-conifer forest (2.2 squirrels/ha). Tree canopy cover was the single best correlate of squirrel density (r = 0.77), with an apparent threshold of 55% canopy cover separating stands with low- from high-density populations. Pradel estimates of annual recruitment were lower in open pine (0.28) than in young (0.35) and mature (0.37) forest. High recruitment was most strongly associated with high understory plant species richness and truffle biomass. Annual survival rates ranged from 45% to 59% and did not vary among cover types. Survival was most strongly associated with understory species richness and forage lichen biomass. Maximum snow depth had a strong negative effect on survival. Rate of per capita increase showed a density-dependent response. Thinning and prescribed burning in ponderosa pine and dry mixed conifer forests to restore stable fire regimes and forest structure might reduce flying squirrel

  2. Contrasting responses of epiphytic and terricolous lichens to variations in forest characteristics in northern boreal ecosystems1

    National Research Council Canada - National Science Library

    St-Laurent, Martin-Hugues; Drapeau, Pierre; Imbeau, Louis; Boudreault, Catherine; Bouchard, Mathieu; Bergeron, Yves

    2015-01-01

    ...) on fruticose epiphytic and terricolous lichen communities across a large region located at the interface between closed-crown boreal forests and northern open woodlands in the province of Quebec (Canada...

  3. Elevated carbon dioxide and ozone alter productivity and ecosystem carbon content in northern temperate forests

    OpenAIRE

    Talhelm, Alan F.; Pregitzer, Kurt S.; Kubiske, Mark E.; Zak, Donald R.; Campany, Courtney E.; Burton, Andrew J; Dickson, Richard E; Hendrey, George R; Isebrands, J G; Lewin, Keith F; Nagy, John; Karnosky, David F.

    2014-01-01

    Three young northern temperate forest communities in the north-central United States were exposed to factorial combinations of elevated carbon dioxide (CO2) and tropospheric ozone (O3) for 11 years. Here, we report results from an extensive sampling of plant biomass and soil conducted at the conclusion of the experiment that enabled us to estimate ecosystem carbon (C) content and cumulative net primary productivity (NPP). Elevated CO2 enhanced ecosystem C content by 11%, whereas elevated O3 d...

  4. Integration of woodland caribou habitat management and forest management in northern Ontario - current status and issues

    Directory of Open Access Journals (Sweden)

    Ted (E.R Armstrong

    1998-03-01

    Full Text Available Woodland caribou {Rangifer tarandus caribou range across northern Ontario, occurring in both the Hudson Bay Lowlands and the Boreal Forest. Woodland caribou extend south well into the merchantable forest, occurring in licensed and/or actively managed Forest Management Units (FMU's across the province. Caribou range has gradually but continuously receded northward over the past century. Since the early 1990's, the Ontario Ministry of Natural Resources (OMNR has been developing and implementing a woodland caribou habitat management strategy in northwestern Ontario. The purpose of the caribou habitat strategy is to maintain woodland caribou occupancy of currently occupied range in northwestern Ontario. Long-term caribou habitat needs and predator-prey dynamics form the basis of this strategy, which requires the development of a landscape-level caribou habitat mosaic across the region within caribou range. This represents a significant change from traditional forest management approaches, which were based partially upon moose (Alces alces habitat management principles. A number of issues and concerns regarding implications of caribou management to the forest industry are being addressed, including short-term and long-term reductions in wood supply and wood quality, and increased access costs. Other related concerns include the ability to regenerate forests to pre-harvest stand conditions, remote tourism concerns, implications for moose populations, and required information on caribou biology and habitat. The forest industry and other stakeholders have been actively involved with the OMNR in attempting to address these concerns, so that caribou habitat requirements are met while ensuring the maintenance of a viable timber industry, other forest uses and the forest ecosystem.

  5. Derivation of soil screening thresholds to protect chisel-toothed kangaroo rat from uranium mine waste in northern Arizona

    Science.gov (United States)

    Hinck, Jo E.; Linder, Greg L.; Otton, James K.; Finger, Susan E.; Little, Edward E.; Tillitt, Donald E.

    2013-01-01

    Chemical data from soil and weathered waste material samples collected from five uranium mines north of the Grand Canyon (three reclaimed, one mined but not reclaimed, and one never mined) were used in a screening-level risk analysis for the Arizona chisel-toothed kangaroo rat (Dipodomys microps leucotis); risks from radiation exposure were not evaluated. Dietary toxicity reference values were used to estimate soil-screening thresholds presenting risk to kangaroo rats. Sensitivity analyses indicated that body weight critically affected outcomes of exposed-dose calculations; juvenile kangaroo rats were more sensitive to the inorganic constituent toxicities than adult kangaroo rats. Species-specific soil-screening thresholds were derived for arsenic (137 mg/kg), cadmium (16 mg/kg), copper (1,461 mg/kg), lead (1,143 mg/kg), nickel (771 mg/kg), thallium (1.3 mg/kg), uranium (1,513 mg/kg), and zinc (731 mg/kg) using toxicity reference values that incorporate expected chronic field exposures. Inorganic contaminants in soils within and near the mine areas generally posed minimal risk to kangaroo rats. Most exceedances of soil thresholds were for arsenic and thallium and were associated with weathered mine wastes.

  6. Termite assemblages in five semideciduous Atlantic Forest fragments in the northern coastland limit of the biome

    Directory of Open Access Journals (Sweden)

    Heitor Bruno de Araújo Souza

    2012-03-01

    Full Text Available Termites are abundant organisms in tropical ecosystems and strongly influence the litter decomposition and soil formation. Despite their importance, few studies about their assemblage structures have been made in Brazilian Atlantic Forest fragments, especially in the area located north of the São Francisco River. This study aims to analyze the assemblage composition of five Atlantic Forest fragments located in the northern biome limit along the Brazilian coast. A standardized sampling protocol of termites was applied in each fragment. Thirty-three termite species belonging to twenty genera and three families were found in the forest fragments. The wood-feeder group was dominant both concerning to species richness and number of encounters in all areas. In sites northern to 7°S, there is an evident simplification of the termite assemblage composition regarding species richness and number of encounters by feeding group. This fact is apparently due to a higher sandy level in soils and to semideciduous character of the vegetation in the northern fragments. Thus, even on the north of São Francisco River, termite biodiversity is heterogeneously spread with highest density of species in the portion between 07°S and São Francisco River mouth (10°29'S.

  7. Assessment of Soil Organic Carbon Stock of Temperate Coniferous Forests in Northern Kashmir

    Directory of Open Access Journals (Sweden)

    Davood A. Dar

    2015-02-01

    Full Text Available  Soil organic carbon (SOC estimation in temperate forests of the Himalaya is important to estimate their contribution to regional, national and global carbon stocks. Physico chemical properties of soil were quantified to assess soil organic carbon density (SOC and SOC CO2 mitigation density at two soil depths (0-10 and 10-20 cms under temperate forest in the Northern region of Kashmir Himalayas India. The results indicate that conductance, moisture content, organic carbon and organic matter were significantly higher while as pH and bulk density were lower at Gulmarg forest site. SOC % was ranging from 2.31± 0.96 at Gulmarg meadow site to 2.31 ± 0.26 in Gulmarg forest site. SOC stocks in these temperate forests were from 36.39 ±15.40 to 50.09 ± 15.51 Mg C ha-1. The present study reveals that natural vegetation is the main contributor of soil quality as it maintained the soil organic carbon stock. In addition, organic matter is an important indicator of soil quality and environmental parameters such as soil moisture and soil biological activity change soil carbon sequestration potential in temperate forest ecosystems.DOI: http://dx.doi.org/10.3126/ije.v4i1.12186International Journal of Environment Volume-4, Issue-1, Dec-Feb 2014/15; page: 161-178

  8. An assessment of the downturn in the forest products sector in the northern region of the United States

    Science.gov (United States)

    C.W. Woodall; W.G. Luppold; P.J. Ince; R.J. Piva; K.E. Skog

    2012-01-01

    The forest industry within the northern region of the U.S. has declined notably in employment, mill numbers, wood consumption, and forest harvests since 2000…a downturn exacerbated by the recession of 2007 to 2009. Longer term industrial decline (since 2000) has been evidenced by reductions in secondary products (e.g., furniture) and print paper manufacturing which can...

  9. Bird species diversity and nesting success in mature, clearcut and shelterwood forest in northern New Hampshire, USA

    Science.gov (United States)

    David I. King; Richard M. DeGraaf

    2000-01-01

    Bird species distribution and predation rates on natural and artificial nests were compared among unmanaged mature, shelterwood, and clearcut northern hardwoods forest to evaluate the effect of these practices on bird populations. Twenty-three of the 48 bird species detected during the study differed significantly in abundance among unmanaged mature forest,...

  10. Seed dispersal turns an experimental plantation on degraded land into a novel forest in urban northern Puerto Rico

    Science.gov (United States)

    Oscar Abelleira; Elvia J. Meléndez Ackerman; Diana García Montiel; John A. Parrotta

    2015-01-01

    Planting tree species with desirable traits may catalyze forest regeneration in increasingly common degraded lands by restoring soil properties and attracting seed dispersers. We sampled forest regeneration in an experimental plantation of Albizia lebbek, an introduced N-fixing species, on a degraded pasture in northern Puerto Rico, 27 years after its establishment. We...

  11. Windthrow and salvage logging in an old-growth hemlock-northern hardwoods forest

    Science.gov (United States)

    Lang, K.D.; Schulte, L.A.; Guntenspergen, G.R.

    2009-01-01

    Although the initial response to salvage (also known as, post-disturbance or sanitary) logging is known to vary among system components, little is known about longer term forest recovery. We examine forest overstory, understory, soil, and microtopographic response 25 years after a 1977 severe wind disturbance on the Flambeau River State Forest in Wisconsin, USA, a portion of which was salvage logged. Within this former old-growth hemlock-northern hardwoods forest, tree dominance has shifted from Eastern hemlock (Tsuga canadensis) to broad-leaf deciduous species (Ulmus americana, Acer saccharum, Tilia americana, Populus tremuloides, and Betula alleghaniensis) in both the salvaged and unsalvaged areas. While the biological legacies of pre-disturbance seedlings, saplings, and mature trees were initially more abundant in the unsalvaged area, regeneration through root suckers and stump sprouts was common in both areas. After 25 years, tree basal area, sapling density, shrub layer density, and seedling cover had converged between unsalvaged and salvaged areas. In contrast, understory herb communities differed between salvaged and unsalvaged forest, with salvaged forest containing significantly higher understory herb richness and cover, and greater dominance of species benefiting from disturbance, especially Solidago species. Soil bulk density, pH, organic carbon content, and organic nitrogen content were also significantly higher in the salvaged area. The structural legacy of tip-up microtopography remains more pronounced in the unsalvaged area, with significantly taller tip-up mounds and deeper pits. Mosses and some forest herbs, including Athyrium filix-femina and Hydrophyllum virginianum, showed strong positive responses to this tip-up microrelief, highlighting the importance of these structural legacies for understory biodiversity. In sum, although the pathways of recovery differed, this forest appeared to be as resilient to the compound disturbances of windthrow

  12. A direct measurement of the stable isotopes of transpired water vapor in a northern Michigan forest

    Science.gov (United States)

    Aron, P.; Poulsen, C. J.; Fiorella, R.

    2016-12-01

    The stable isotopes of oxygen and hydrogen in water vapor track hydrologic processes as phase changes of water preferentially partition heavy isotopes (18O and 2H) into the condensate and light isotopes (16O and 1H) into the vapor phase. As a result, the isotopic composition of water vapor can be used to identify water fluxes and cycling through natural environments. Forest water vapor is comprised of terrestrial (evaporation and transpiration) and atmospheric (tropospheric mixing, precipitation, and condensation) components. Within the isotopic record of forest water vapor, stable isotopes of transpired water (δT) comprise an important component but is typically either assumed to be non-fractionating or estimated indirectly. However, on small time scales (minutes to hours), non-steady state forest systems experience isotopic enrichment during early morning and late afternoon when transpiration rates are low. We deployed two Picarro Cavity Ring-Down spectrometers (L2120-i and L2130-i, respectively) in the University of Michigan Biological Station (UMBS) forest near Pellston, MI to measure the isotopic composition of near-surface ambient water vapor and the transpired vapor component directly. Both ambient and transpired water vapor were measured at three heights above the forest floor (2, 10, and 20 m) during August 2016. To measure species-specific water use, δT was measured on red maple (Acer rubrum) and northern red oak (Quercus rubra), two of the dominant tree types in the UMBS forest. This work represents the first direct measurement of δT in the UMBS forest and will help decouple local and species-specific hydrologic cycling. Beyond UMBS, this measurement will allow for a better understanding of species-specific plant hydraulics and help identify when the steady state approximation of transpiration is valid, which can be used to study water use and forest health.

  13. Anthropogenic Decline of Ecosystem Services Threatens the Integrity of the Unique Hyrcanian (Caspian) Forests in Northern Iran

    OpenAIRE

    Ardavan Zarandian; Himlal Baral; Ahmad R. Yavari; Hamid R. Jafari; Nigel E Stork; Ling, Matthew A.; Hamid Amirnejad

    2016-01-01

    The unique Hyrcanian (Caspian) forests of northern Iran provide vital ecosystem services for local and global communities. We assess the status and trends of key ecosystem services in this region where native forest conversion has accelerated to make way for housing and farm development. This is a mountainous forested area that is valuable for both conservation and multiple human uses including recreation and farming. It contains globally significant natural habitats for in situ conservation ...

  14. Ecological and biological considerations for sustainable management of non-timber forest products in northern forests

    Science.gov (United States)

    Luc C. Duchesne; John C. Zasada; Iain. Davidson-Hunt

    2001-01-01

    With a current output of over $241 million per year, non-timber forest products (NTFPs) contribute significantly to the welfare of rural and First Nations communities in Canada. Maple sap products, wild mushrooms, and wild fruits are the most important NTFPs for consumption both in Canada and abroad. However, because of increased access to international markets by...

  15. The Evolution of USDA Forest Service Experimental Forest Research on Northern Conifers in the Northeast

    Science.gov (United States)

    Laura S. Kenefic; Nicole S. Rogers

    2017-01-01

    The degraded stand pictured in this 1955 USDA Forest Service photograph from Maine was dominated by balsam fir (Abies balsamea), red maple (Acer rubrum), paper birch (Betula papyrifera), and American beech (Fagus grandifolia). Stands such as these were typical of second-growth, lowland...

  16. Local Consequences of Applying International Norms: Differences in the Application of Forest Certification in Northern Sweden, Northern Finland, and Northwest Russia

    Directory of Open Access Journals (Sweden)

    Johanna Johansson

    2009-12-01

    Full Text Available Forest certification, developed in the early 1990s, is a process in which independent assessors grant use of the certification label to producers who meet certain environmental and social criteria set for their forest products. This label was quickly seen to offer a market advantage and to signal corporate social and environmental responsibility. This paper focuses on international norms pertaining to environmental and indigenous rights, as manifested in cases of Forest Stewardship Council (FSC- and Programme for the Endorsement of Forest Certification (PEFC-compatible certification, and how these norms have been applied domestically and perceived locally in different states. Case studies are drawn from northern Sweden, northern Finland, and three regions in northwest Russia. The studies illustrate that the choice and implementation of certification type depend considerably on national infrastructure and market characteristics and result in substantial differences in the impact that international norms have at the local level.

  17. Development and evaluation of local communities incentive programs for improving the traditional forest management:A case study of North-ern Zagros forests, Iran

    Institute of Scientific and Technical Information of China (English)

    Jalal Henareh Khalyani; Manouchehr Namiranian; S. M. Heshmatol Vaezin; Jahangir Feghhi

    2014-01-01

    We examined the local community incentive programs to improve traditional forest management in three forested villages in Baneh city, Kurdistan province in the northern Zagros forests of western Iran. Zagros forests cover 6.07 million ha and support rich plant and animal diversity. Changes in local community social and economic sys-tems and the inefficiency of traditional forest management led to a criti-cal situation in the stability of forest regeneration in recent decades. Due to a shortage of productive and arable lands and resulting unemployment and poverty, people overexploited the Zagros forests. Outside interven-tion in traditional forest management creates conflicts between local peoples and forest management organizations. To achieve sustainable forest management, including forest resources conservation and im-provement of natural resource based livelihoods of communities, it is desirable to implement Forestry Incentive Programs (FIP) based on the important functions of forests. Detailed information on the so-cio-economics of communities, the effect of forests on local livelihoods, and lists of products extracted from the forest were obtained from a sur-vey of local communities though questionnaire, interview and observa-tion. We studied 276 households in three villages and completed 76 ques-tionnaires by householders in the quantitative analysis. Sampling was performed by simple random sampling (SRS). The needs of rural com-munities, such as livestock husbandry, mainly arise from the characteris-tics and environmental features of villages. We identified the driving forces, pressures, status, impacts and responses (DPSIR) to design incen-tive programs, by DPSIR analysis and interaction analysis. Evaluation of local community benefits from forests showed that in order to improve forest management, 319 dollars per year would be needed by each family as an incentive in 2010 to prevent lopping and firewood collecting, the main causes of forest degradation.

  18. Sensitivity of ALOS/PALSAR imagery to forest degradation by fire in northern Amazon

    Science.gov (United States)

    Martins, Flora da Silva Ramos Vieira; dos Santos, João Roberto; Galvão, Lênio Soares; Xaud, Haron Abrahim Magalhães

    2016-07-01

    We evaluated the sensitivity of the full polarimetric Phased Array type L-band Synthetic Aperture Radar (PALSAR), onboard the Advanced Land Observing Satellite (ALOS), to forest degradation caused by fires in northern Amazon, Brazil. We searched for changes in PALSAR signal and tri-dimensional polarimetric responses for different classes of fire disturbance defined by fire frequency and severity. Since the aboveground biomass (AGB) is affected by fire, multiple regression models to estimate AGB were obtained for the whole set of coherent and incoherent attributes (general model) and for each set separately (specific models). The results showed that the polarimetric L-band PALSAR attributes were sensitive to variations in canopy structure and AGB caused by forest fire. However, except for the unburned and thrice burned classes, no single PALSAR attribute was able to discriminate between the intermediate classes of forest degradation by fire. Both the coherent and incoherent polarimetric attributes were important to explain AGB variations in tropical forests affected by fire. The HV backscattering coefficient, anisotropy, double-bounce component, orientation angle, volume index and HH-VV phase difference were PALSAR attributes selected from multiple regression analysis to estimate AGB. The general regression model, combining phase and power radar metrics, presented better results than specific models using coherent or incoherent attributes. The polarimetric responses indicated the dominance of VV-oriented backscattering in primary forest and lightly burned forests. The HH-oriented backscattering predominated in heavily and frequently burned forests. The results suggested a greater contribution of horizontally arranged constituents such as fallen trunks or branches in areas severely affected by fire.

  19. Bedrock Nitrogen Contributes to Increased Carbon Storage in Temperate Conifer Forests of Northern California, USA

    Science.gov (United States)

    Morford, S. L.; Houlton, B. Z.; Dahlgren, R. A.

    2010-12-01

    Identifying mechanisms by which nitrogen (N) enters ecosystems is crucial to modeling carbon (C) storage and earth system responses to rising CO2 emissions. Paradigms of nutrient cycling posit that N enters ecosystems solely from the atmosphere; however, rocks contain 99% of all fixed N on Earth, implying a potentially widespread source of ecologically available N. We tested the hypothesis that bedrock N contributes to increased N fertility and C storage of temperate conifer forests underlain by N-rich bedrock in northern California, USA. We used a paired sampling design to measure total N and C, and N stable isotope ratios (15N/14N) of surface mineral soils, bedrock, and foliage from similar forests that differed in parent material: the first site on N-rich (680 ppm N) metasedimentary rock, the second site on N-poor (55 ppm N) igneous rock. In addition, we performed a regional analysis of C storage in aboveground tree biomass using Forest Inventory and Analysis (FIA) plot data (n = 82) from conifer forests on N-rich and N-poor bedrock to examine for C by N interactions at the regional scale. The N content of soils and conifer needles was elevated by more than 50% in the forest underlain by N-rich bedrock, with soil C pools elevated by 60% in N-rich sites. Further, 15N/14N of rock, soils, and plants were indistinguishable in sites underlain by N-rich lithology, whereas foliar 15N/14N from N-poor site was depleted 20‰ relative to rock. Finally, the regional data pointed to substantial effects of N-rich rock on total forest C storage; ecosystem C pools were 40% higher in forests with geologic N than sites with N-poor bedrock minerals. These results suggest that rock weathering can profoundly alter ecosystem N and C cycles, implying an overlooked pathway of N input to terrestrial ecosystems.

  20. Comparative phylogeographic analyses illustrate the complex evolutionary history of threatened cloud forests of northern Mesoamerica.

    Directory of Open Access Journals (Sweden)

    Juan Francisco Ornelas

    Full Text Available Comparative phylogeography can elucidate the influence of historical events on current patterns of biodiversity and can identify patterns of co-vicariance among unrelated taxa that span the same geographic areas. Here we analyze temporal and spatial divergence patterns of cloud forest plant and animal species and relate them to the evolutionary history of naturally fragmented cloud forests--among the most threatened vegetation types in northern Mesoamerica. We used comparative phylogeographic analyses to identify patterns of co-vicariance in taxa that share geographic ranges across cloud forest habitats and to elucidate the influence of historical events on current patterns of biodiversity. We document temporal and spatial genetic divergence of 15 species (including seed plants, birds and rodents, and relate them to the evolutionary history of the naturally fragmented cloud forests. We used fossil-calibrated genealogies, coalescent-based divergence time inference, and estimates of gene flow to assess the permeability of putative barriers to gene flow. We also used the hierarchical Approximate Bayesian Computation (HABC method implemented in the program msBayes to test simultaneous versus non-simultaneous divergence of the cloud forest lineages. Our results show shared phylogeographic breaks that correspond to the Isthmus of Tehuantepec, Los Tuxtlas, and the Chiapas Central Depression, with the Isthmus representing the most frequently shared break among taxa. However, dating analyses suggest that the phylogeographic breaks corresponding to the Isthmus occurred at different times in different taxa. Current divergence patterns are therefore consistent with the hypothesis of broad vicariance across the Isthmus of Tehuantepec derived from different mechanisms operating at different times. This study, coupled with existing data on divergence cloud forest species, indicates that the evolutionary history of contemporary cloud forest lineages is complex

  1. Comparative phylogeographic analyses illustrate the complex evolutionary history of threatened cloud forests of northern Mesoamerica.

    Science.gov (United States)

    Ornelas, Juan Francisco; Sosa, Victoria; Soltis, Douglas E; Daza, Juan M; González, Clementina; Soltis, Pamela S; Gutiérrez-Rodríguez, Carla; de los Monteros, Alejandro Espinosa; Castoe, Todd A; Bell, Charles; Ruiz-Sanchez, Eduardo

    2013-01-01

    Comparative phylogeography can elucidate the influence of historical events on current patterns of biodiversity and can identify patterns of co-vicariance among unrelated taxa that span the same geographic areas. Here we analyze temporal and spatial divergence patterns of cloud forest plant and animal species and relate them to the evolutionary history of naturally fragmented cloud forests--among the most threatened vegetation types in northern Mesoamerica. We used comparative phylogeographic analyses to identify patterns of co-vicariance in taxa that share geographic ranges across cloud forest habitats and to elucidate the influence of historical events on current patterns of biodiversity. We document temporal and spatial genetic divergence of 15 species (including seed plants, birds and rodents), and relate them to the evolutionary history of the naturally fragmented cloud forests. We used fossil-calibrated genealogies, coalescent-based divergence time inference, and estimates of gene flow to assess the permeability of putative barriers to gene flow. We also used the hierarchical Approximate Bayesian Computation (HABC) method implemented in the program msBayes to test simultaneous versus non-simultaneous divergence of the cloud forest lineages. Our results show shared phylogeographic breaks that correspond to the Isthmus of Tehuantepec, Los Tuxtlas, and the Chiapas Central Depression, with the Isthmus representing the most frequently shared break among taxa. However, dating analyses suggest that the phylogeographic breaks corresponding to the Isthmus occurred at different times in different taxa. Current divergence patterns are therefore consistent with the hypothesis of broad vicariance across the Isthmus of Tehuantepec derived from different mechanisms operating at different times. This study, coupled with existing data on divergence cloud forest species, indicates that the evolutionary history of contemporary cloud forest lineages is complex and often lineage

  2. [Odocoileus virginianus diet (Artiodactyla: Cervidae) in a temperate forest of Northern Oaxaca, Mexico].

    Science.gov (United States)

    González, Graciela; Briones-Salas, Miguel

    2012-03-01

    The Sierra Madre de Oaxaca region, located in the Northern state of Oaxaca, Mexico, is an area of forest ecosystems subject to high exploitation rates, although in some areas its temperate forests are conserved by indigenous community initiatives that live there. We analyzed the diet of white tailed-deer (Odocoileus virginianus) in the localities of Santa Catarina Lachatao and San Miguel Amatlán from June 1998 to August 1999. Sampling was done during both the wet and dry seasons, and included the observation of browsing traces (238 observations), microhistological analysis of deer feces (28 deer pellet-groups), and two stomach content analysis. The annual diet of white-tailed deer was composed of 42 species from 23 botanical families. The most represented families in the diet of this deer were Fagaceae, Asteraceae, Ericaceae and Fabaceae. There were significant differences in the alpha diversity of the diet during the wet and dry seasons (H'=2.957 and H'=1.832, respectively). The similarity percentage between seasons was 56%. Differences in plant species frequency were significantly higher during the wet season. Herbaceous plants made up the greatest percentage of all the species consumed. The preferred species throughout the year were Senecio sp. (shrub), Sedum dendroideum (herbaceous), Arctostaphylos pungens (shrub) and Satureja macrostema (shrub). Diet species richness was found to be lower than that observed in a tropical forest (Venezuela), tropical dry forest (Mexico) and temperate deciduous and mixed forest (Mexico), but similar to the diet species richness observed in a tropical dry forest (Costa Rica) and temperate coniferous and deciduous forests (USA).

  3. Forest Crown Cover Estimation in Northern Boreal and Temperate European Forest

    Science.gov (United States)

    Sirro, Laura; Hame, Tuomas; Ahola, Heikki; Lonnqvist, Anne

    2012-04-01

    A method for forest crown cover estimation using high resolution optical earth observation data was developed and tested at four study sites in Europe. Crown cover was estimated using the probability estimation method of VTT and Image2006 data. The accuracy of the crown cover predictions was assessed using reference data that were collected by visual interpretation of very high resolution aerial and space borne imagery. The average crown cover values in the reference data varied from 17 % to 86 % and in the predictions from 18 % to 80 %. The absolute root mean square error of the crown cover predictions varied between 14 % and 33 %. The results of the study showed that it is possible to map forest crown cover with twenty to thirty meter spatial resolution optical earth observation data using the single pixel values. However, understanding the variable results at different sites requires further investigation.

  4. Hydro-climatic variability and forest fires in Mexicos northern temperate forests

    OpenAIRE

    José Návar; Liliana Lizárraga-Mendiola

    2013-01-01

    Global warming is likely modifying the hydrological cycle of forested watersheds. This report set as objectives to: a) assess the hydrological variables interception loss, I, potential and actual evapotranspiration, E, Et, runoff, Q, and soil moisture content, θ; b) evaluate whether these variables are presenting consistent trends or oscillations that can be associated to global warming or climate variability; and c) relate θ to the number of wildfires and the burned area in Durango, Mexico. ...

  5. [Effects of simulated nitrogen deposition on soil respiration in northern subtropical deciduous broad-leaved forest].

    Science.gov (United States)

    Hu, Zheng-hua; Li, Han-mao; Yang, Yan-ping; Chen, Shu-tao; Li, Cen-zi; Shen, Shuang-he

    2010-08-01

    To investigate the effects of elevated nitrogen deposition on forest soil respiration, a simulated nitrogen deposition field experiment was conducted in northern subtropical deciduous broad-leave forest from April 2008 to April 2009. Nitrogen treatments included the control (no N addition, CK), low-N [50 kg x (hm2 x a)(-1), T(L)], medium-N [100 kg x (hm2 x a)(-1), T(M)], and high-N [150 kg x (hm2 x a)(-1), T(H)]. The respiration rates were measured by a static chamber-gas chromatograph method. Results showed that nitrogen deposition did not change the seasonal and daily variation patterns of soil respiration. Compared to the control, T(L), T(M) and T(H) treatments reduced soil annual average respiration rates by 8.51%, 9.74% and 11.24%, respectively. Meanwhile, T(L), T(M) and T(H) treatments decreased daily average soil respiration rates by 4.42%, 11.09% and 12.17%, respectively. Significant relationship was found between soil respiration rate and soil temperature. The Q10 (temperature sensitivity coefficients) for soil respiration of CK, T(L), T(M), and T(H) treatments were 2.53, 3.22, 2.64 and 2.92, respectively. Our findings suggested that nitrogen deposition reduced soil respiration, and increased soil respiration temperature sensitivity in northern subtropical deciduous broad-leave forest.

  6. The impact of bryophytes on the carbon stocks of northern boreal forest soils

    Science.gov (United States)

    Hagemann, U.; Moroni, M. T.; Shaw, C. H.; Kurz, W. A.

    2012-04-01

    Dead organic matter (DOM), organic layer, and mineral soil carbon (C) dynamics in cool and humid northern boreal forests are expected to differ from those of drier or warmer boreal forests, because processes such as paludification and woody debris (WD) burial within the organic layer by overgrowing moss are more pronounced in regions with low average temperatures, vigorous moss layers, and long fire-return intervals. However, very few studies have provided field-measured data for these mostly remote regions. Hence, C cycling models such as the Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3) have rarely been validated with field data from northern boreal forest soils, resulting in large uncertainties for estimated C stocks in a large proportion of the boreal forest ecozone. We present (i) measured data on organic layer and mineral soil (0-45 cm) C stocks in 18 old-growth and disturbed high-boreal black spruce stands in Labrador, Canada; (ii) a comparison of field-measured soil C stocks with those predicted using the CBM-CFS3; and (iii) special characteristics of the DOM and soil C dynamics of northern boreal forest soils that require modifications of model parameters and structure. Measured organic layer C stocks (30.4-47.4 Mg C ha-1) were within the range reported for other boreal forests. However, mineral soil C stocks (121.5-208.1 Mg C ha-1) contributed 58-76% to total ecosystem C stocks. Mineral soil C stocks were thus considerably higher than observed in other upland boreal forests in drier or warmer regions, but similar to values reported for black spruce on poorly drained sites and peat soils. In addition, large amounts of deadwood C (4.7-18.2 Mg C ha-1) were found to be buried within the organic layer, contributing up to 31% to total organic layer C stocks. The comparison of field-measured and CBM-CFS3 modeled C stocks showed that organic layer and mineral soil DOM in Labrador black spruce stands likely decays at lower rates than assumed by CBM

  7. Forest ecosystem vulnerability assessment and synthesis for northern Wisconsin and western Upper Michigan: a report from the Northwoods Climate Change Response Framework project

    Science.gov (United States)

    Maria K. Janowiak; Louis R. Iverson; David J. Mladenoff; Emily Peters; Kirk R. Wythers; Weimin Xi; Leslie A. Brandt; Patricia R. Butler; Stephen D. Handler; P. Danielle Shannon; Chris Swanston; Linda R. Parker; Amy J. Amman; Brian Bogaczyk; Christine Handler; Ellen Lesch; Peter B. Reich; Stephen Matthews; Matthew Peters; Anantha Prasad; Sami Khanal; Feng Liu; Tara Bal; Dustin Bronson; Andrew Burton; Jim Ferris; Jon Fosgitt; Shawn Hagan; Erin Johnston; Evan Kane; Colleen Matula; Ryan O' Connor; Dale Higgins; Matt St. Pierre; Jad Daley; Mae Davenport; Marla R. Emery; David Fehringer; Christopher L. Hoving; Gary Johnson; David Neitzel; Michael Notaro; Adena Rissman; Chadwick Rittenhouse; Robert. Ziel

    2014-01-01

    Forest ecosystems across the Northwoods will face direct and indirect impacts from a changing climate over the 21st century. This assessment evaluates the vulnerability of forest ecosystems in the Laurentian Mixed Forest Province of northern Wisconsin and western Upper Michigan under a range of future climates. Information on current forest conditions, observed climate...

  8. Development of a high-resolution binational vegetation map of the Santa Cruz River riparian corridor and surrounding watershed, southern Arizona and northern Sonora, Mexico

    Science.gov (United States)

    Wallace, Cynthia S.A.; Villarreal, Miguel L.; Norman, Laura M.

    2011-01-01

    This report summarizes the development of a binational vegetation map developed for the Santa Cruz Watershed, which straddles the southern border of Arizona and the northern border of Sonora, Mexico. The map was created as an environmental input to the Santa Cruz Watershed Ecosystem Portfolio Model (SCWEPM) that is being created by the U.S. Geological Survey for the watershed. The SCWEPM is a map-based multicriteria evaluation tool that allows stakeholders to explore tradeoffs between valued ecosystem services at multiple scales within a participatory decision-making process. Maps related to vegetation type and are needed for use in modeling wildlife habitat and other ecosystem services. Although detailed vegetation maps existed for the U.S. side of the border, there was a lack of consistent data for the Santa Cruz Watershed in Mexico. We produced a binational vegetation classification of the Santa Cruz River riparian habitat and watershed vegetation based on NatureServe Terrestrial Ecological Systems (TES) units using Classification And Regression Tree (CART) modeling. Environmental layers used as predictor data were derived from a seasonal set of Landsat Thematic Mapper (TM) images (spring, summer, and fall) and from a 30-meter digital-elevation-model (DEM) grid. Because both sources of environmental data are seamless across the international border, they are particularly suited to this binational modeling effort. Training data were compiled from existing field data for the riparian corridor and data collected by the NM-GAP (New Mexico Gap Analysis Project) team for the original Southwest Regional Gap Analysis Project (SWReGAP) modeling effort. Additional training data were collected from core areas of the SWReGAP classification itself, allowing the extrapolation of the SWReGAP mapping into the Mexican portion of the watershed without collecting additional training data.

  9. SOZOLOGICAL CHARACTERISTIC OF VEGETATION OF FORESTS AND SHRUBS OF THE NORTHERN BLACK SEA REGION

    Directory of Open Access Journals (Sweden)

    I. V. Solomakha

    2015-12-01

    Full Text Available As a result of sociological analysis found that in the vegetation cover of forests and shrubs in the Northern Black Sea found 88 view of rare and endangered plants. For 37 species, there are phytocoenotic table, the data on the other - are induced for that literary materials herbarium. They have a different distribution in the classes of the vegetation on the study territory: Pulsatillo-Pinetea sylvestris (13 species, Dactilydo glomeratae-Populetea tremulae (13, Festuco-Brometea (9, Rhamno-Prunetea (8, Nerio-Tamaricetea (7, Salicetea purpureae (5, Robinietea (3, Alnetea glutinosae (3, Franguletea (3. Some rare and endangered communities of the territory need to be included in the «Green Book of Ukraine». Key words: vegetation, syntaxonomy, forests, shrubs, sozological characteristic, Northen Black Sea region.

  10. Influence of repeated prescribed fire on tree growth and mortality in Pinus resinosa forests, northern Minnesota

    Science.gov (United States)

    Bottero, Alessandra; D'Amato, Anthony W.; Palik, Brian J.; Kern, Christel C.; Bradford, John B.; Scherer, Sawyer S.

    2017-01-01

    Prescribed fire is widely used for ecological restoration and fuel reduction in fire-dependent ecosystems, most of which are also prone to drought. Despite the importance of drought in fire-adapted forests, little is known about cumulative effects of repeated prescribed burning on tree growth and related response to drought. Using dendrochronological data in red pine (Pinus resinosa Ait.)-dominated forests in northern Minnesota, USA, we examined growth responses before and after understory prescribed fires between 1960 and 1970, to assess whether repeated burning influences growth responses of overstory trees and vulnerability of overstory tree growth to drought. We found no difference in tree-level growth vulnerability to drought, expressed as growth resistance, resilience, and recovery, between areas receiving prescribed fire treatments and untreated forests. Annual mortality rates during the period of active burning were also low (less than 2%) in all treatments. These findings indicate that prescribed fire can be effectively integrated into management plans and climate change adaptation strategies for red pine forest ecosystems without significant short- or long-term negative consequences for growth or mortality rates of overstory trees.

  11. [Diversity and dynamics of a high sub-Andean forest from Northern Andes, Colombia].

    Science.gov (United States)

    Restrepo, Jesús Oswaldo Velásquez; Maniguaje, Nancy Lorena; Duque, Alvaro Javier

    2012-06-01

    The sub-Andean forests are characterized by a high biodiversity, but little is known about their natural dynamics. In order to generate new information, this study assessed two permanent plots of one hectare each, in the Northern Andean area of the Western Cordillera, Colombia. Methodology included the evaluation of diversity patterns, above ground biomass (AGB) dynamics, and mortality and recruitment rates. Besides, we used the Fisher's Alpha index to calculate species diversity. Forest dynamics and AGB were evaluated in both plots by means of three censuses carried out within a nine years period. In total, we found 1 664 individuals with diameter at breast height (DBH)> or =10cm belonging to 222 species, 113 genera and 60 families. Mean species richness was of 156 species/ha and a mean Fisher's Alpha index of 56.2/ha. The mortality rate was 0.88% and recruitment was 1.16%, which did not allow to lay any external effect of global warming or climate change on individual forest dynamics. However, the mean AGB was 243.44+/-9.82t/ha, with an annual average increase of 2.9t/ha, a higher value than the one reported in other studies of high sub-Andean forests, which suggests that equilibrium in terms of the AGB have not yet been reached. Besides, according to field observations, a recovery process, from a disturbance that occurred in the past, might be on his way.

  12. Tranquilidad and hardship in the forest : livelihoods and perceptions of Camba forest dwellers in the northern Bolivian Amazon

    NARCIS (Netherlands)

    Henkemans, A.B.

    2002-01-01

    Sustainable management of tropical forests relies largely on the interest of forest dwelling people in long-term forest extraction and their capacity to prevent forest degradation by other forest users. This study discusses the role of the forest in the livelihoods and perceptions of Camba (multi-e

  13. Paleomagnetism and magnetostratigraphy of the lower Glen Canyon and upper Chinle Groups, Jurassic-Triassic of northern Arizona and northeast Utah

    Science.gov (United States)

    Molina-Garza, Roberto S.; Geissman, John W.; Lucas, Spencer G.

    2003-04-01

    Twenty-eight selected sites (individual beds) in the Moenave Formation at the Echo Cliffs, northern Arizona, strata give a Hettangian paleomagnetic pole at 63.7°N, 59.7°E (dp = 2.6°, dm = 5.1°). The Wingate Sandstone and Rock Point Formation at Comb Ridge, southeast Utah, provide a Rhaetian paleopole at 57.4°N, 56.6°E (N = 16 sites; dp = 3.4, dm = 6.5). High unblocking temperatures (>600°C), high coercivity, and data analyses indicate that the characteristic magnetization is primarily a chemical remanence residing in hematite. The Hettangian and Rhaetian poles are statistically indistinguishable (at 95% confidence), they resemble existing data for the Glen Canyon Group, and they provide further validation to the J1 cusp of the North American apparent pole wander path (APWP). The red siltstone and upper members of the Chinle Group, on the south flank of the Uinta Mountains, northern Utah, define a Rhaetian pole at 51.6°N, 70.9°E (N = 20 sites; dp = 3.5°, dm = 6.9°). The Gartra and upper members of the Chinle Group in the north flank of the Uinta Mountains, give paleopoles at 52.0°N, 100.3°E (N = 6 sites; dp = 5.4°, dm = 10.5°) and 50.9°N, 50.1°E (N = 5 sites; dp = 8.8°, dm = 17.5°), respectively. These data indicate no significant rotation of the Uinta Mountains with respect to the craton. In total, data for the plateau and its bordering region of Cenozoic uplifts support estimates of small rotation of the plateau and provide evidence against the hypothesis of a Late Triassic standstill of the North American APWP. Our magnetostratigraphic results are consistent with lithographic and biostratigraphic data that place the Triassic-Jurassic boundary within the Dinosaur Canyon Member of the Moenave Formation, not at a regional hiatus.

  14. The science and politics of forest management in Northern Nicaragua after hurricane Felix (2007)

    Science.gov (United States)

    Rossi Idarraga, Esteban

    This dissertation examines the ecological effects of hurricane Felix (2007) in Northern Nicaragua as well as the socio-political factors that influenced forest management efforts in hurricane impacted locations. Specifically, this research focused on the following questions: first, what were the regional damage patterns caused by hurricane Felix on the forests of Northern Nicaragua? Second, what stand and tree attributes explain observed post-hurricane damage patterns? And, third, why were post-hurricane management efforts unsuccessful? The first dissertation article characterizes the intensity and spatial distribution of forest damage after hurricane Felix using satellite imagery from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor and aerial photographs. Results indicated that Broadleaf forests experienced larger damage (>75% trees blown down) than Pine forest, and that Enhanced Vegetation Index data (EVI), obtained from the MODIS sensor, can adequately depict post-hurricane damage in tropical forests. The agreement between the obtained EVI damage map and the reference data set ranged from 91% in high-damage locations to 85% in low-damage locations, with 86% overall agreement. The second dissertation article describes the relationship between hurricane damage patterns and ecological variables at the local level. Specifically, it characterizes the relationship between tree-and-stand attributes (i.e. DBH, height, density, basal area) and wind damage, using field data. Findings indicate that tree attributes such as DBH and height strongly influenced the amount and type of wind damage and that stand attributes such as maximum canopy height and distance to the hurricane path were also predictive of the amount of damage. Observed differences in damage patterns among broadleaf and pine forests were strongly correlated with the height to diameter ratio (H/D). Field observations showed that while post-hurricane regeneration was abundant in broadleaf

  15. The influece of forest gaps on some properties of humus in a managed beech forest, northern Iran

    Science.gov (United States)

    Vajari, K. A.

    2015-10-01

    The present research focuses on the effect of eight-year-old artificially created gaps on some properties of humus in managed beech-dominated stand in Hyrcanian forest of northern Iran. In this study, six-teen gaps were sampled in site and were classified into four classes (small, medium, large, and very large) with four replications for each. Humus sampling was carried out at the centre and at the cardinal points within each gap as well as in the adjacent closed stand, separately, as composite samples. The variables of organic carbon, P, K, pH, and total N were measured for each sample. It was found that the gap size had significant effect only on total N (%) and organic carbon (%) in beech stand. The amount of potassium clearly differed among three positions in beech forest. The adjacent stand had higher significantly potassium than center and edge of gaps. Different amount of potassium was detected in gap center and gap edge. Comparison of humus properties between gaps and its adjacent stand pointed to the higher amount of potassium in adjacent stand than that in gaps but there was no difference between them regarding other humus properties. According to the results, it can be concluded that there is relatively similar condition among gaps and closed adjacent stands in terms of humus properties eight years after logging in the beech stand.

  16. Revised lithostratigraphy of the Sonsela Member (Chinle Formation, Upper Triassic in the Southern Part of Petrified Forest National Park, Arizona.

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    Jeffrey W Martz

    Full Text Available BACKGROUND: Recent revisions to the Sonsela Member of the Chinle Formation in Petrified Forest National Park have presented a three-part lithostratigraphic model based on unconventional correlations of sandstone beds. As a vertebrate faunal transition is recorded within this stratigraphic interval, these correlations, and the purported existence of a depositional hiatus (the Tr-4 unconformity at about the same level, must be carefully re-examined. METHODOLOGY/PRINCIPAL FINDINGS: Our investigations demonstrate the neglected necessity of walking out contacts and mapping when constructing lithostratigraphic models, and providing UTM coordinates and labeled photographs for all measured sections. We correct correlation errors within the Sonsela Member, demonstrate that there are multiple Flattops One sandstones, all of which are higher than the traditional Sonsela sandstone bed, that the Sonsela sandstone bed and Rainbow Forest Bed are equivalent, that the Rainbow Forest Bed is higher than the sandstones at the base of Blue Mesa and Agate Mesa, that strata formerly assigned to the Jim Camp Wash beds occur at two stratigraphic levels, and that there are multiple persistent silcrete horizons within the Sonsela Member. CONCLUSIONS/SIGNIFICANCE: We present a revised five-part model for the Sonsela Member. The units from lowest to highest are: the Camp Butte beds, Lot's Wife beds, Jasper Forest bed (the Sonsela sandstone/Rainbow Forest Bed, Jim Camp Wash beds, and Martha's Butte beds (including the Flattops One sandstones. Although there are numerous degradational/aggradational cycles within the Chinle Formation, a single unconformable horizon within or at the base of the Sonsela Member that can be traced across the entire western United States (the "Tr-4 unconformity" probably does not exist. The shift from relatively humid and poorly-drained to arid and well-drained climatic conditions began during deposition of the Sonsela Member (low in the Jim Camp

  17. Evaluation of funnel traps for characterizing the bark beetle (Coleoptera: Scolytidae) communities in ponderosa pine forests of north-central Arizona.

    Science.gov (United States)

    Hayes, Christopher J; DeGomez, Tom E; Clancy, Karen M; Williams, Kelly K; McMillin, Joel D; Anhold, John A

    2008-08-01

    Lindgren funnel traps baited with aggregation pheromones are widely used to monitor and manage populations of economically important bark beetles (Coleoptera: Scolytidae). This study was designed to advance our understanding of how funnel trap catches assess bark beetle communities and relative abundance of individual species. In the second year (2005) of a 3-yr study of the bark beetle community structure in north-central Arizona pine (Pinus spp.) forests, we collected data on stand structure, site conditions, and local bark beetle-induced tree mortality at each trap site. We also collected samples of bark from infested (brood) trees near trap sites to identify and determine the population density of bark beetles that were attacking ponderosa pine, Pinus ponderosa Douglas ex Lawson, in the area surrounding the traps. Multiple regression models indicated that the number of Dendroctonus and Ips beetles captured in 2005 was inversely related to elevation of the trap site, and positively associated with the amount of ponderosa pine in the stand surrounding the site. Traps located closer to brood trees also captured more beetles. The relationship between trap catches and host tree mortality was weak and inconsistent in forest stands surrounding the funnel traps, suggesting that trap catches do not provide a good estimate of local beetle-induced tree mortality. However, pheromone-baited funnel trap data and data from gallery identification in bark samples produced statistically similar relative abundance profiles for the five species of bark beetles that we examined, indicating that funnel trap data provided a good assessment of species presence and relative abundance.

  18. Winter climate change affects growing-season soil microbial biomass and activity in northern hardwood forests.

    Science.gov (United States)

    Durán, Jorge; Morse, Jennifer L; Groffman, Peter M; Campbell, John L; Christenson, Lynn M; Driscoll, Charles T; Fahey, Timothy J; Fisk, Melany C; Mitchell, Myron J; Templer, Pamela H

    2014-11-01

    Understanding the responses of terrestrial ecosystems to global change remains a major challenge of ecological research. We exploited a natural elevation gradient in a northern hardwood forest to determine how reductions in snow accumulation, expected with climate change, directly affect dynamics of soil winter frost, and indirectly soil microbial biomass and activity during the growing season. Soils from lower elevation plots, which accumulated less snow and experienced more soil temperature variability during the winter (and likely more freeze/thaw events), had less extractable inorganic nitrogen (N), lower rates of microbial N production via potential net N mineralization and nitrification, and higher potential microbial respiration during the growing season. Potential nitrate production rates during the growing season were particularly sensitive to changes in winter snow pack accumulation and winter soil temperature variability, especially in spring. Effects of elevation and winter conditions on N transformation rates differed from those on potential microbial respiration, suggesting that N-related processes might respond differently to winter climate change in northern hardwood forests than C-related processes.

  19. El «Painted Desert & Petrified Forest», centro turístico, en Arizona (U. S. A.

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    Neutra, Richard J.

    1965-10-01

    Full Text Available The «Painted Desert & Petrified Forest» built by the National Park Service has a main centre for visitors, a motel, a communitary social centre, houses for the staff, and a small model of a rural school for the children of the families living at the site. This «Desert & Forest» is a national monument and constitutes a beautiful source of interest to visitors, who will find much to learn in admiring the expressive remants of the past. This creation by Neutra is clearly indicative of the author's personal style, and it emphasizes the horizontal outlines, in order to better blend with the landscape.Las edificaciones construidas en el Painted Desert por el National Park Service albergan: un centro para visitantes, un motel, un centro social comunitario, un centro comercial, viviendas para los empleados, etc., y un pequeño modelo de escuela rural para los niños de las familias que allí habitan. El Painted Desert & Petrified Forest constituye un bello atractivo, sumamente aleccionador para el visitante, a través de los expresivos restos del pasado. Esta obra de Neutra, de una plástica sugestiva, Ueva el sello original de su autor, acusando la horizontalidad extrema de sus lineas dominantes.

  20. Postfire Succession of Ants (Hymenoptera: Formicidae) Nesting in Dead Wood of Northern Boreal Forest.

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    Boucher, Philippe; Hébert, Christian; Francoeur, André; Sirois, Luc

    2015-10-01

    Dead wood decomposition begins immediately after tree death and involves a large array of invertebrates. Ecological successions are still poorly known for saproxylic organisms, particularly in boreal forests. We investigated the use of dead wood as nesting sites for ants along a 60-yr postfire chronosequence in northeastern coniferous forests. We sampled a total of 1,625 pieces of dead wood, in which 263 ant nests were found. Overall, ant abundance increased during the first 30 yr after wildfire, and then declined. Leptothorax cf. canadensis Provancher, the most abundant species in our study, was absent during the first 2 yr postfire, but increased steadily until 30 yr after fire, whereas Myrmica alaskensis Wheeler, second in abundance, was found at all stages of succession in the chronosequence. Six other species were less frequently found, among which Camponotus herculeanus (Linné), Formica neorufibarbis Emery, and Formica aserva Forel were locally abundant, but more scarcely distributed. Dead wood lying on the ground and showing numerous woodborer holes had a higher probability of being colonized by ants. The C:N ratio was lower for dead wood colonized by ants than for noncolonized dead wood, showing that the continuous occupation of dead wood by ants influences the carbon and nitrogen dynamics of dead wood after wildfire in northern boreal forests. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Ectomycorrhizal Cortinarius species participate in enzymatic oxidation of humus in northern forest ecosystems.

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    Bödeker, Inga T M; Clemmensen, Karina E; de Boer, Wietse; Martin, Francis; Olson, Åke; Lindahl, Björn D

    2014-07-01

    In northern forests, belowground sequestration of nitrogen (N) in complex organic pools restricts nutrient availability to plants. Oxidative extracellular enzymes produced by ectomycorrhizal fungi may aid plant N acquisition by providing access to N in macromolecular complexes. We test the hypotheses that ectomycorrhizal Cortinarius species produce Mn-dependent peroxidases, and that the activity of these enzymes declines at elevated concentrations of inorganic N. In a boreal pine forest and a sub-arctic birch forest, Cortinarius DNA was assessed by 454-sequencing of ITS amplicons and related to Mn-peroxidase activity in humus samples with- and without previous N amendment. Transcription of Cortinarius Mn-peroxidase genes was investigated in field samples. Phylogenetic analyses of Cortinarius peroxidase amplicons and genome sequences were performed. We found a significant co-localization of high peroxidase activity and DNA from Cortinarius species. Peroxidase activity was reduced by high ammonium concentrations. Amplification of mRNA sequences indicated transcription of Cortinarius Mn-peroxidase genes under field conditions. The Cortinarius glaucopus genome encodes 11 peroxidases - a number comparable to many white-rot wood decomposers. These results support the hypothesis that some ectomycorrhizal fungi--Cortinarius species in particular--may play an important role in decomposition of complex organic matter, linked to their mobilization of organically bound N.

  2. Climate change science applications and needs in forest ecosystem management: a workshop organized as part of the northern Wisconsin Climate Change Response Framework Project

    Science.gov (United States)

    Leslie Brandt; Chris Swanston; Linda Parker; Maria Janowiak; Richard Birdsey; Louis Iverson; David Mladenoff; Patricia. Butler

    2012-01-01

    Climate change is leading to direct and indirect impacts on forest tree species and ecosystems in northern Wisconsin. Land managers will need to prepare for and respond to these impacts, so we designed a workshop to identify forest management approaches that can enhance the ability of ecosystems in northern Wisconsin to cope with climate change and address how National...

  3. Factorial analysis on forest canopy density restoration in the burned area of northern Great Xing'an Mountains, China

    Institute of Scientific and Technical Information of China (English)

    XIEFu-ju; XIAODu-ning; LIXiu-zhen; WANGXu-gao; SHIBao-dong

    2005-01-01

    The restoration of forest landscape has drawn much attention since the catastrophic fire took place on the northern slope of Great Xing'an Mountains in 1987. Forest canopy density, which has close relation to forest productivity, was selected as a key factor to find how much the forest quality was changed 13 years after fire, and how fire severity, regeneration way and terrain factors influenced the restoration of forest canopy density, based on forest inventory data in China, and using Kendall Bivariate Correlation Analysis, and Distances Correlation Analysis. The results showed that fire severity which was inversely correlated with forest canopy density grade was an initial factor among all that selected. Regeneration way which did not remarkably affect forest canopy density restoration in short period, may shorten the cycle of forest succession and promote the forest productivity of conophorium in the future, Among the three terrain factors, the effect of slope was the strongest, the position on slope was the second and the aspect was the last.

  4. Regeneration Responses to Management for Old-Growth Characteristics in Northern Hardwood-Conifer Forests

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    Aviva J. Gottesman

    2017-02-01

    Full Text Available Successful tree regeneration is essential for sustainable forest management, yet it can be limited by the interaction of harvesting effects and multiple ecological drivers. In northern hardwood forests, for example, there is uncertainty whether low-intensity selection harvesting techniques will result in adequate and desirable regeneration. Our research is part of a long-term study that tests the hypothesis that a silvicultural approach called “structural complexity enhancement” (SCE can accelerate the development of late-successional forest structure and functions. Our objective is to understand the regeneration dynamics following three uneven-aged forestry treatments with high levels of retention: single-tree selection, group selection, and SCE. Regeneration density and diversity can be limited by differing treatment effects on or interactions among light availability, competitive environment, substrate, and herbivory. To explore these relationships, manipulations and controls were replicated across 2 ha treatment units at two Vermont sites. Forest inventory data were collected pre-harvest and periodically over 13 years post-harvest. We used mixed effects models with repeated measures to evaluate the effect of treatment on seedling and sapling density and diversity (Shannon–Weiner H’. The treatments were all successful in recruiting a sapling class with significantly greater sapling densities compared to the controls. However, undesirable and prolific beech (Fagus americana sprouting dominates some patches in the understory of all the treatments, creating a high degree of spatial variability in the competitive environment for regeneration. Multivariate analyses suggest that while treatment had a dominant effect, other factors were influential in driving regeneration responses. These results indicate variants of uneven-aged systems that retain or enhance elements of stand structural complexity—including old-growth characteristics

  5. Operational impacts to residual stands following ground-based skidding in Hyrcanian Forest, northern Iran

    Institute of Scientific and Technical Information of China (English)

    Meghdad Jourgholami

    2012-01-01

    Hyrcanian (Caspian) Forest in northern Iran has a richness of biological diversity,with endemic and endangered species.The usage of ground-based skidding is well accepted practice for the extraction of timber from the forest,but this operation has tended to cause the greatest environmental problems.The aims of the study were to evaluate and comparison of operational impacts,residual stand damage,regeneration,and to quantify these effects such as:the extent of the damage,wounding patterns,size and distribution after logging operations that utilized two different methods:short-log and long-log.A Timberjack cable skidder was used and the study location was in the Kheyrud Forest.Post harvesting assessment of damage to the residual stand was compared along skid trail by 100% inventory method and also for the assessment of regeneration damage along winching strips.The results show that along winching strips the percentage of damage to the regeneration was 44% and 36%,while the tree damages along skid trails reached 2.3% and 4.1% in the short-log and long-log methods,respectively.The greatest average amount of damage to a bole occurred along the first 1 m up from the ground (97%) and also within 4 m of the skidder centerline (80%).These results show that the short-log method causes less damage to the residual stand than the long-log method.Tree location to skidder trail appears to have a significant effect on the number and height of scars on a tree.Well designed and constructed trails should he wide enough to allow wood extraction from the forest.Damage to the residual stand might be reduced by proper planning and training of logging crews.

  6. Climate-Driven Changes Within the Larch Forest of Northern Siberia

    Science.gov (United States)

    Kharuk, V.

    2015-12-01

    Thanks to the support of NASA's Carbon Cycle and Ecosystem Focus Area programs, joint NASA/ Siberian Branch of the Russian Academy of Sciences studies have been conducted throughout Siberia. The overall objective has been to obtain field and satellite measurements to examine carbon stocks and track changes in forests across this vast area. In this presentation, we discuss some of the finding from this 25+ year collaboration' i.e., observed climate-driven changes within larch communities in northern Siberia. Field measurements and satellite data, including Terra/MODIS, Landsat, GRACE and QuickBird were used for analysis of forest conditions. The following results will be discussed. (1). At the northern limit of larch (Larix gmelinii) range (i.e.,~72°N) tree mortality was observed during the cooling period from the 16th century to the beginning of the 19th century. Post- Little Ice Age (LIA) trees re-establishment followed warming temperatures by the middle of the19th century. The current tree line has recovered to the pre-LIA line location although tree heights and stand densities are comparatively lower. The mean rate of upward migration was found to be 0.35 m yr-1 (with a range of 0.21-0.58). (2) The migration of the "dark needle conifers" (DNC: Abies sibirica, Pinus sibirica, Picea obovata) into the southern margin zone of larch dominated forest was documented. Meanwhile, within the traditional DNC range decline and mortality of both Siberian pine and fir were observed and attributed, primarily, due to an increased drought. (3) Within Central Siberia larch growth is limited by early summer temperatures and available water from thawing permafrost. Larch tree ring width (TRW) correlated with early summer temperatures and water vapor pressure (r = 0.73 and r = 0.69, respectively), drought (SPEI; r = 0.68-0.82), snow accumulation (r = 0.61), previous year precipitation (r = 0.63) and soil water anomalies (r = 0.79). Larch TRW growth and Gross Primary Productivity

  7. Impact of Distance from the Forest Edge on The Wild Bee Diversity on the Northern Slope of Mount Slamet

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    Imam Widhiono

    2016-09-01

    Full Text Available In agricultural landscape in northern slope of Mount Slamet, diversity of wild bee species as pollinator depend on forested habitats. This study aimed to assess the effects of distance from the forest edge on the diversity of wild bees on strawberry and tomato crops. This study was conducted from July 2014 to October 2014. The experimental fields contained tomato and strawberry with a total area of 4 ha (2 ha each and divided into five plots based on distance from the forest edge (0, 50, 100, 150, and 200 m. Wild bee was catched with  kite netting  in 7.00 -9.00 in ten consecutive days. Wild bee diversity differed according to distance from the forest edge, the highest value was at 0 m for strawberry plots (H’ = 2.008, E = 0.72 and Chao1= 16 and for tomato plots, the highest diversity was at 50 m from the forest edge (H’ = 2.298, E = 0.95 and Chao1= 11 and the lowest was at 200 m in both plots. Wild bee species richness and abundance decreased with distance, resulting in the minimum diversity and abundance of wild bee at 200 m from forest edge in both crops. How to CiteWidhiono, I., & Sudiana, E. (2016. Impact of Distance from the Forest Edge on The Wild Bee Diversity on the Northern Slope of Mount Slamet. Biosaintifika: Journal of Biology & Biology Education, 8(2, 148-154.

  8. Interactions across spatial scales among forest dieback, fire, and erosion in northern New Mexico landscapes

    Science.gov (United States)

    Allen, C.D.

    2007-01-01

    Ecosystem patterns and disturbance processes at one spatial scale often interact with processes at another scale, and the result of such cross-scale interactions can be nonlinear dynamics with thresholds. Examples of cross-scale pattern-process relationships and interactions among forest dieback, fire, and erosion are illustrated from northern New Mexico (USA) landscapes, where long-term studies have recently documented all of these disturbance processes. For example, environmental stress, operating on individual trees, can cause tree death that is amplified by insect mortality agents to propagate to patch and then landscape or even regional-scale forest dieback. Severe drought and unusual warmth in the southwestern USA since the late 1990s apparently exceeded species-specific physiological thresholds for multiple tree species, resulting in substantial vegetation mortality across millions of hectares of woodlands and forests in recent years. Predictions of forest dieback across spatial scales are constrained by uncertainties associated with: limited knowledge of species-specific physiological thresholds; individual and site-specific variation in these mortality thresholds; and positive feedback loops between rapidly-responding insect herbivore populations and their stressed plant hosts, sometimes resulting in nonlinear "pest" outbreak dynamics. Fire behavior also exhibits nonlinearities across spatial scales, illustrated by changes in historic fire regimes where patch-scale grazing disturbance led to regional-scale collapse of surface fire activity and subsequent recent increases in the scale of extreme fire events in New Mexico. Vegetation dieback interacts with fire activity by modifying fuel amounts and configurations at multiple spatial scales. Runoff and erosion processes are also subject to scale-dependent threshold behaviors, exemplified by ecohydrological work in semiarid New Mexico watersheds showing how declines in ground surface cover lead to non

  9. Uncertainties in detecting decadal change in extractable soil elements in Northern Forests

    Science.gov (United States)

    Bartlett, O.; Bailey, S. W.; Ducey, M. J.

    2016-12-01

    Northern Forest ecosystems have been or are being impacted by land use change, forest harvesting, acid deposition, atmospheric CO2 enrichment, and climate change. Each of these has the potential to modify soil forming processes, and the resulting chemical stocks. Horizontal and vertical variations in concentrations complicate determination of temporal change. This study evaluates sample design, sample size, and differences among observers as sources of uncertainty when quantifying soil temporal change over regional scales. Forty permanent, northern hardwood, monitoring plots were established on the White Mountain National Forest in central New Hampshire and western Maine. Soil pits were characterized and sampled by genetic horizon at plot center in 2001 and resampled again in 2014 two-meters on contour from the original sampling location. Each soil horizon was characterized by depth, color, texture, structure, consistency, boundaries, coarse fragments, and roots from the forest floor to the upper C horizon, the relatively unaltered glacial till parent material. Laboratory analyses included pH in 0.01 M CaCl2 solution and extractable Ca, Mg, Na, K, Al, Mn, and P in 1 M NH4OAc solution buffered at pH 4.8. Significant elemental differences were identified by genetic horizon from paired t-tests (p ≤ 0.05) indicate temporal change across the study region. Power analysis, 0.9 power (α = 0.05), revealed sampling size was appropriate within this region to detect concentration change by genetic horizon using a stratified sample design based on topographic metrics. There were no significant differences between observers' descriptions of physical properties. As physical properties would not be expected to change over a decade, this suggests spatial variation in physical properties between the pairs of sampling pits did not detract from our ability to detect temporal change. These results suggest that resampling efforts within a site, repeated across a region, to quantify

  10. New environmental policy instruments to realize forest expansion in Flanders (northern Belgium): A base for smart regulation?

    NARCIS (Netherlands)

    Gossum, Van P.; Ledene, L.; Arts, B.J.M.; Vreese, De R.; Langenhove, Van G.; Verheyen, K.

    2009-01-01

    This paper evaluates the current instrument mix, designs options for smart regulation and estimates the support base of new instruments for the forest expansion policy in Flanders (northern Belgium). The framework applied is a combination of theories on instrument choice (ICT), policy transfer and l

  11. Differential sensitivity to climate change of C and N cycling processes across soil horizons in a northern hardwood forest

    Science.gov (United States)

    Jorge Durán; Jennifer L. Morse; Alexandra Rodríguez; John L. Campbell; Lynn M. Christenson; Charles T. Driscoll; Timothy J. Fahey; Melany C. Fisk; Myron J. Mitchell; Pamela H. Templer; Peter M. Groffman

    2017-01-01

    Climate of the northern hardwood forests of North America will become significantly warmer in the coming decades. Associated increases in soil temperature, decreases in water availability and changes in winter snow pack and soil frost are likely to affect soil carbon (C) and nitrogen (N) cycling. Most studies of the effects of climate change on soil function have...

  12. Long-term effects of fuel treatments on aboveground biomass accumulation in ponderosa pine forests of the northern Rocky Mountains

    Science.gov (United States)

    Kate A. Clyatt; Christopher R. Keyes; Sharon M. Hood

    2017-01-01

    Fuel treatments in ponderosa pine forests of the northern Rocky Mountains are commonly used to modify fire behavior, but it is unclear how different fuel treatments impact the subsequent production and distribution of aboveground biomass, especially in the long term. This research evaluated aboveground biomass responses 23 years after treatment in two silvicultural...

  13. Changing values and the impact on land use and social networks in the northern forest region: a qualitative examination

    Science.gov (United States)

    Jean Dedam; Rodney Zwick

    2007-01-01

    Patterns of land ownership and economics are changing in the Northern Forest Region of New York, Vermont, New Hampshire, and Maine. The percentage of people living in the region who work in the resource extraction industry has become much smaller. Tourism and outdoor recreation are promoted as economic substitutes that will provide an alternate use of the natural...

  14. USDA Midwest and Northern Forests Regional Climate Hub: Assessment of climate change vulnerability and adaptation and mitigation strategies

    Science.gov (United States)

    The Midwest Regional Climate Hub covers the States of Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Ohio, and Wisconsin and represents one of the most extensive and intensive agricultural systems in the world. The Northern Forests Climate Sub Hub shares this footprint and represents people...

  15. Vegetation composition and altitudinal distribution of Andean rain forests in El Angel and Guandera reserves, northern Ecuador

    NARCIS (Netherlands)

    Moscol Olivera, M.C.; Cleef, A.M.

    2009-01-01

    Patterns of vascular plant species composition and structure of the remaining rain forest of the Andean Cordillera in northern Ecuador were studied in two reserves: Guandera and El Angel. Thirty three plots located between 3300 and 3700 in were examined along two altitudinal transects crossing the U

  16. Interactive effects of historical logging and fire exclusion on ponderosa pine forest structure in the northern Rockies.

    Science.gov (United States)

    Naficy, Cameron; Sala, Anna; Keeling, Eric G; Graham, Jon; DeLuca, Thomas H

    2010-10-01

    Increased forest density resulting from decades of fire exclusion is often perceived as the leading cause of historically aberrant, severe, contemporary wildfires and insect outbreaks documented in some fire-prone forests of the western United States. Based on this notion, current U.S. forest policy directs managers to reduce stand density and restore historical conditions in fire-excluded forests to help minimize high-severity disturbances. Historical logging, however, has also caused widespread change in forest vegetation conditions, but its long-term effects on vegetation structure and composition have never been adequately quantified. We document that fire-excluded ponderosa pine forests of the northern Rocky Mountains logged prior to 1960 have much higher average stand density, greater homogeneity of stand structure, more standing dead trees and increased abundance of fire-intolerant trees than paired fire-excluded, unlogged counterparts. Notably, the magnitude of the interactive effect of fire exclusion and historical logging substantially exceeds the effects of fire exclusion alone. These differences suggest that historically logged sites are more prone to severe wildfires and insect outbreaks than unlogged, fire-excluded forests and should be considered a high priority for fuels reduction treatments. Furthermore, we propose that ponderosa pine forests with these distinct management histories likely require distinct restoration approaches. We also highlight potential long-term risks of mechanical stand manipulation in unlogged forests and emphasize the need for a long-term view of fuels management.

  17. Atmospheric black carbon deposition and characterization of biomass burning tracers in a northern temperate forest

    Science.gov (United States)

    Santos, F.; Fraser, M. P.; Bird, J. A.

    2014-10-01

    Aerosol black carbon (BC) is considered the second largest contributor to global warming after CO2, and is known to increase the atmosphere's temperature, decrease the albedo in snow/ice, and influence the properties and distribution of clouds. BC is thought to have a long mean residence time in soils, and its apparent stability may represent a significant stable sink for atmospheric CO2. Despite recent efforts to quantify BC in the environment, the quantification of BC deposition rates from the atmosphere to terrestrial ecosystems remains scarse. To better understand the contribution of atmospheric BC inputs to soils via dry deposition and its dominant emission sources, atmospheric fine particle (PM2.5) were collected at the University of Michigan Biological Station from July to September in 2010 and 2011. PM2.5 samples were analyzed for organic C, BC, and molecular markers including particulate sugars, carboxylic acids, n-alkanes, polycyclic aromatic hydrocarbons, and cholestane. Average atmospheric BC concentrations in northern Michigan were 0.048 ± 0.06 μg m-3 in summer 2010, and 0.049 ± 0.064 μg m-3 in summer 2011. Based on atmospheric concentrations, particulate deposition calculations, and documented soil BC, we conclude that atmospheric deposition is unlikely to comprise a significant input pathway for BC in northern forest ecosystem. The major organic tracers identified in fine particulates (e.g. levoglucosan and docosanoic acid) suggest that ambient PM2.5 concentrations were mainly influenced by biomass burning and epicuticular plant waxes. These results provide baseline data needed for future assessments of atmospheric BC in rural temperate forests.

  18. Towards operational remote sensing of forest carbon balance across Northern Europe

    Directory of Open Access Journals (Sweden)

    P. Olofsson

    2008-05-01

    Full Text Available Monthly averages of ecosystem respiration (ER, gross primary production (GPP and net ecosystem exchange (NEE over Scandinavian forest sites were estimated using regression models driven by air temperature (AT, absorbed photosynthetically active radiation (APAR and vegetation indices. The models were constructed and evaluated using satellite data from Terra/MODIS and measured data collected at seven flux tower sites in northern Europe. Data used for model construction was excluded from the evaluation. Relationships between ground measured variables and the independent variables were investigated.

    It was found that the enhanced vegetation index (EVI at 250 m resolution was highly noisy for the coniferous sites, and hence, 1 km EVI was used for the analysis. Linear relationships between EVI and the biophysical variables were found: correlation coefficients between EVI and GPP, NEE, and AT ranged from 0.90 to 0.79 for the deciduous data, and from 0.85 to 0.67 for the coniferous data. Due to saturation, there were no linear relationships between normalized difference vegetation index (NDVI and the ground measured parameters found at any site. APAR correlated better with the parameters in question than the vegetation indices. Modeled GPP and ER were in good agreement with measured values, with more than 90% of the variation in measured GPP and ER being explained by the coniferous models. The site-specific respiration rate at 10°C (R10 was needed for describing the ER variation between sites. Even though monthly NEE was modeled with less accuracy than GPP, 61% and 75% (dec. and con., respectively of the variation in the measured time series was explained by the model. These results are important for moving towards operational remote sensing of forest carbon balance across Northern Europe.

  19. Multi-year lags between forest browning and soil respiration at high northern latitudes.

    Directory of Open Access Journals (Sweden)

    Ben Bond-Lamberty

    Full Text Available High-latitude northern ecosystems are experiencing rapid climate changes, and represent a large potential climate feedback because of their high soil carbon densities and shifting disturbance regimes. A significant carbon flow from these ecosystems is soil respiration (R(S, the flow of carbon dioxide, generated by plant roots and soil fauna, from the soil surface to atmosphere, and any change in the high-latitude carbon cycle might thus be reflected in R(S observed in the field. This study used two variants of a machine-learning algorithm and least squares regression to examine how remotely-sensed canopy greenness (NDVI, climate, and other variables are coupled to annual R(S based on 105 observations from 64 circumpolar sites in a global database. The addition of NDVI roughly doubled model performance, with the best-performing models explaining ∼62% of observed R(S variability. We show that early-summer NDVI from previous years is generally the best single predictor of R(S, and is better than current-year temperature or moisture. This implies significant temporal lags between these variables, with multi-year carbon pools exerting large-scale effects. Areas of decreasing R(S are spatially correlated with browning boreal forests and warmer temperatures, particularly in western North America. We suggest that total circumpolar R(S may have slowed by ∼5% over the last decade, depressed by forest stress and mortality, which in turn decrease R(S. Arctic tundra may exhibit a significantly different response, but few data are available with which to test this. Combining large-scale remote observations and small-scale field measurements, as done here, has the potential to allow inferences about the temporal and spatial complexity of the large-scale response of northern ecosystems to changing climate.

  20. The amount and quality of dead trees in a mixed beech forest with different management histories in northern Iran

    Directory of Open Access Journals (Sweden)

    KIOMARS SEFIDI

    2014-10-01

    Full Text Available Sefidi K, Etemad V. 2014. The amount and quality of dead trees in a mixed beech forest with different management histories in northern Iran. Biodiversitas 15: 162-168. Dead tree (fallen logs and snags, is regarded as an important ecological component of forests on which many forest dwelling species depend, yet its relation to management history in Caspian forest has gone unreported. The aim of research aim was to compare the amounts of dead tree in the forests with historically different intensities of management, including: forests with the long term implication of management (Patom, the short term implication of management (Namekhaneh which were compared with semi virgin forest (Gorazbon. The number of 215 individual dead trees were recorded and measured at 79 sampling locations. ANOVA revealed volume of dead tree in the form and decay classes significantly differ within sites and dead volume in the semi virgin forest significantly higher than managed sites. Comparing the amount of dead tree in three sites showed that, dead tree volume related with management history and significantly differ in three study sites. Reaching their highest in virgin site and their lowest in the site with the long term implication of management, it was concluded that forest management cause reduction of the amount of dead tree. Forest management history affect the forest's ability to generate dead tree specially in a large size, thus managing this forest according to ecological sustainable principles require a commitment to maintaining stand structure that allow, continued generation of dead tree in a full range of size.

  1. Silica uptake and release in live and decaying biomass in a northern hardwood forest.

    Science.gov (United States)

    Clymans, Wim; Conley, Daniel J; Battles, John J; Frings, Patrick J; Koppers, Mary Margaret; Likens, Gene E; Johnson, Chris E

    2016-11-01

    In terrestrial ecosystems, a large portion (20-80%) of the dissolved Si (DSi) in soil solution has passed through vegetation. While the importance of this "terrestrial Si filter" is generally accepted, few data exist on the pools and fluxes of Si in forest vegetation and the rate of release of Si from decomposing plant tissues. We quantified the pools and fluxes of Si through vegetation and coarse woody debris (CWD) in a northern hardwood forest ecosystem (Watershed 6, W6) at the Hubbard Brook Experimental Forest (HBEF) in New Hampshire, USA. Previous work suggested that the decomposition of CWD may have significantly contributed to an excess of DSi reported in stream-waters following experimental deforestation of Watershed 2 (W2) at the HBEF. We found that woody biomass (wood + bark) and foliage account for approximately 65% and 31%, respectively, of the total Si in biomass at the HBEF. During the decay of American beech (Fagus grandifolia) boles, Si loss tracked the whole-bole mass loss, while yellow birch (Betula alleghaniensis) and sugar maple (Acer saccharum) decomposition resulted in a preferential Si retention of up to 30% after 16 yr. A power-law model for the changes in wood and bark Si concentrations during decomposition, in combination with an exponential model for whole-bole mass loss, successfully reproduced Si dynamics in decaying boles. Our data suggest that a minimum of 50% of the DSi annually produced in the soil of a biogeochemical reference watershed (W6) derives from biogenic Si (BSi) dissolution. The major source is fresh litter, whereas only ~2% comes from the decay of CWD. Decay of tree boles could only account for 9% of the excess DSi release observed following the experimental deforestation of W2. Therefore, elevated DSi concentrations after forest disturbance are largely derived from other sources (e.g., dissolution of BSi from forest floor soils and/or mineral weathering). © 2016 The Authors. Ecology, published by Wiley Periodicals

  2. Forest Transitions and Rural Livelihoods: Multiple Pathways of Smallholder Teak Expansion in Northern Laos

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    Jonathan Newby

    2014-06-01

    Full Text Available Smallholder teak (Tectona grandis plantations have been identified as a potentially valuable component of upland farming systems in northern Laos that can contribute to a “livelihood transition” from subsistence-oriented swidden agriculture to a more commercially-oriented farming system, thereby bringing about a “forest transition” at the landscape scale. In recent years, teak smallholdings have become increasingly prominent in the province of Luang Prabang, especially in villages close to Luang Prabang City. In this paper, we draw on a household survey conducted in five teak-growing villages and case studies of different household types to explore the role that small-scale forestry has played in both livelihood and land-use transitions. Drawing on a classification of forest transitions, we identify three transition pathways that apply in the study villages—the “economic development” pathway, the “smallholder, tree-based, land-use intensification” pathway, and the “state forest policy” pathway. The ability of households to integrate teak into their farming system, manage the woodlots effectively, and maintain ownership until the plantation reaches maturity varies significantly between these pathways. Households with adequate land resources but scarce labor due to the effects of local economic development are better able to establish and hold onto teak woodlots, but less able to adopt beneficial management techniques. Households that are land-constrained are motivated to follow a path of land-used intensification, but need more productive agroforestry systems to sustain incomes over time. Households that are induced to plant teak mainly by land-use policies that threaten to deprive them of their land, struggle to efficiently manage or hold on to their woodlots in the long term. Thus, even when it is smallholders driving the process of forest transition via piecemeal land-use changes, there is potential for resource

  3. An investigation of sulfur concentrations in soils and pine needles on Chinde Mesa, Petrified Forest National Park, Arizona

    Energy Technology Data Exchange (ETDEWEB)

    Gladney, E.S.; Ferenbaugh, R.W.; Stallings, E.A.; Jones, E.A.; Candelaria, L.M.; Nelson, L.A.; Lundstrom, C. [Los Alamos National Lab., NM (United States); Bowker, R.G. [Alma Coll., MI (United States). Dept. of Biology

    1993-03-01

    Sulfur measurements in different age groups of pinon pine needles and adjacent soil samples from ten sampling sites at Petrified Forest National Park were determined using combustion elemental analysis and chromatographic techniques. The primary goal was to establish base-line levels for elemental sulfur in the Park. Sulfur levels in foliage and soils were evaluated using analysis of variance techniques. No significant differences were found in foliage sulfur concentrations among the 10 sampling sites; however, trees within sites were significantly different. Needles of different ages did not differ significantly in sulfur content. Although average needle sulfur concentrations were similar to those found in other parks throughout the Southwest, the average soil sulfur concentrations were extremely high, approximately 308% of the foliage values. Soil sulfur concentrations also differed significantly among the 10 sampling sites and at different depths in the soil. Statistical differences were evident in soils sampled at the four compass points (N, S, E, W) around each tree, and the north samples had the highest concentrations. These differences imply that large numbers of samples are needed to identify small effects from anthropogenic inputs of sulfur into the system or that the effects must be large relative to the differences among sampling sites and individual trees in order to be detected.

  4. Chemical investigation on wood tree species in a temperate forest, east-northern Romania

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    Teaca, C. A.

    2007-02-01

    Full Text Available A quantitative evaluation of wood chemical components for some tree species in a forest area from east-northern Romania is presented here, through a comparative study from 1964 to 2000. Investigation upon the wood tree-rings in a Quercus robur L. tree species, as a dominant species, as regards its chemical composition and structure of the natural polymer constituents - cellulose and lignin - was also performed through chemical methods to separate the main wood components, FT-IR spectroscopy, and thermogravimetry. Having in view the impact of climate and external factors (such as pollutant depositions, some possible correlations between wood chemical composition and its further use can be made. The FT-IR spectra give evidence of differences in the frequency domains of 3400-2900 cm-1 and 1730-1640 cm-1, due to some interactions between the chemical groups (OH, C=O. The crystallinity index of cellulose presents variations in the oak wood tree-rings. Thermogravimetry analyses show different behaviour of cellulose at thermal decomposition, as a function of radial growth and tree’s height. A preliminary chemical investigation of oak wood sawdust shows a relatively high content of mineral elements (ash, compared with a previous study performed in 1964, fact that may indicate an intense drying process of the oak tree, a general phenomenon present in European forests for this species.

  5. Multilocus analysis of intraspecific differentiation in three endemic bird species from the northern Neotropical dry forest.

    Science.gov (United States)

    Arbeláez-Cortés, Enrique; Milá, Borja; Navarro-Sigüenza, Adolfo G

    2014-01-01

    isolation resulting in the present phylogeographic structure, likely a result of historical climate fluctuations that have fragmented and reconnected the Neotropical dry forest. This study contributes to a growing body of evidence indicating active diversification of endemic lineages in the northern Neotropical dry forest region.

  6. A floristic survey of the Hyrcanian forests in Northern Iran, using two lowland-mountain transects

    Institute of Scientific and Technical Information of China (English)

    Alireza Naqinezhad; Hassan Zare-Maivan; Hamid Gholizadeh

    2015-01-01

    We investigated the floristic composition of the Hyrcanian forests and the related forest-steppe ecotone in Northern Iran by using two long ecological transects, from lowland to upper mountain areas. The study was conducted during 2008 and 2009 and yielded the identification of 395 plant taxa belonging to 233 genera and 78 families. Dicots with 300 taxa were the richest groups of the flora, followed by monocots with 75 taxa, pteridophytes with 18 species, and gymnosperms with two species. The largest families were Asteraceae (33 taxa); Rosaceae (32 taxa); and Poa-ceae (30 taxa), and the most diverse genera included Carex (15 taxa); Alchemilla (7 taxa); and Poa, Geranium and Acer (6 taxa each). Hemicryptophytes were the most dominant life forms in the area (40%); followed by geo-phytes (31.4%); phanerophytes (15.4%); therophytes (11.4%);and chamaephytes (1.8%). Phytogeographically, Euro-Siberian/Irano-Turanian elements (86 taxa, 21.8%) and Euro-Siberian elements (85 taxa, 21.5%) were the most common chorotypes in the area. Out of 395 taxa, 66 taxa (16.7%) were endemics and subendemics in Iran, of which 26 taxa were exclusively endemics of Iran. According to the IUCN Red List Categories, 48 threatened plant taxa were found in the study area. Plant diversity, life form, and chorotypes in the current study were compared with similar transect studies in other areas of the Hyrcanian forests and in different altitudinal belts, using Sørenson similarity indices. Floristic composition of the surveyed transects demonstrated almost 50% similarity between them.

  7. Landscape structure in the northern coast of Paraná state, a hotspot for the brazilian Atlantic Forest conservation

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    Érico Emed Kauano

    2012-10-01

    Full Text Available The "Serra do Mar" region comprises the largest remnant of the Brazilian Atlantic Forest. The coast of the Paraná State is part of the core area of the "Serra do Mar" corridor and where actions for biodiversity conservation must be planned. In this study we aimed at characterizing the landscape structure in the APA-Guaraqueçaba, the largest protected area in this region, in order to assist environmental policies of this region. Based on a supervised classification of a mosaic of LANDSAT-5-TM satellite images (from March 2009, we developed a map (1:75,000 scale with seven classes of land use and land cover and analyzed the relative quantities of forests and modified areas in slopes and lowlands. The APA-Guaraqueçaba is comprised mainly by the Dense Ombrophilous Forest (68.6% of total area and secondary forests (9.1%, indicating a forested landscape matrix; anthropogenic and bare soil areas (0.8% and the Pasture/Grasslands class (4.2% were less representative. Slopes were less fragmented and more preserved (96.3% of Dense Ombrophilous Forest and secondary forest than lowlands (71.3%, suggesting that restoration initiatives in the lowlands must be stimulated in this region. We concluded that most of the region sustains well-conserved ecosystems, highlighting the importance of Paraná northern coast for the biodiversity maintenance of the Atlantic Forest.

  8. Forest fires and PM10 pollution: the March 2012 case in Northern Spain

    Science.gov (United States)

    Rasilla Álvarez, Domingo; García Codron, Juan Carlos; Carracedo Martín, Virginia

    2016-04-01

    Forest fires are one of the largest sources of particulate matter, carbon monoxide, volatile organic compounds and other pollutants at regional scale. They significantly impact on local air quality and human health, even far from their original sources. March 2012 was one of the largest fire activity late winter and early spring seasons across northern Spain and Portugal. Official statistics from the Spanish and Portuguese authorities show that, during that month, approximately 35.000 ha were burned, representing the top March season in Cantabria (N. Spain) and the northern distritos of Portugal since 1981, most of them occurring in the mountainous areas, as depicted from the FIRMS database (https://firms.modaps.eosdis.nasa.gov/). At the same time, an analysis of the pollution data (Airbase dataset; http://www.eea.europa.eu/) show an increase in PM10 average values and exceedences of the limit values across the same area simultaneously or immediately after the main fire activity episodes. A comprehensive analysis of this fire and pollution event was undertaken to analyze the possible contribution of forest fires and other sources of PM10 to the high levels of this pollutant at ground level. Besides statistics of fire activity, satellite "hot spots" and ground level pollution data, we have included in our analysis meteorological records (synoptic stations, upper air soundings), backtrajectories (http://ready.arl.noaa.gov/HYSPLIT.php) and dust forecast models (https://www.bsc.es/earth-sciences/mineral-dust/catalogo-datos-dust). The results show a good agreement between the spatial and temporal variability of the levels of PM10 and the direction of the pollution plumes downwind the forest fires. The activity was mostly concentrated during 3 events, the first one between February 25th to March 3rd; the second spanning from 10th to 17th, and the last one, the most severe of the three, at the end of March. The climatological background was favourable, because most of the

  9. A preliminary summary of a seismic-refraction survey in the vicinity of the Tonto Forest Observatory, Arizona

    Science.gov (United States)

    Roller, J.C.; Jackson, W.H.; Warren, D.H.; Healy, J.H.

    1964-01-01

    The U.S. Geological Survey complete d a seismic-refraction survey in the vicinity of the Tonto Forest Seismological Observatory (T.F.S.O.) in April and May 1964. More than 1200 km of reversed profiles were surveyed to determine the crustal structure and crustal and upper mantle velocities in this area. The purpose of this work was to provide information on wave-propagation paths of seismic events recorded at T.F.S.O. and to improve the performance of the Observatory in locating and identifying these events. First arrivals indicate that the Mohorovicic discontinuity dips to the northeast by as much as 6 degrees under T.F.S.O., and may even be displaced vertically by as much as 5 km immediately north of the Observatory near the boundary of the Basin and Range a n d t he Colorado Plateau Provinces. A preliminary examination of the first arrivals indicates that the crust at T.F.S.O. is at least 30 km thick and is made up of at least two seismic layers. A thin veneer at the surface with a velocity of approximately 4 km/sec is underlain by a layer with a velocity of approximately 5.9 km/sec to 6.1 km/sec. An intermediate layer with velocity of 6.6 to 7.0 km/sec is probably present in the lower crust, but is not revealed by first arrivals. The velocity of seismic waves in the upper mantle is about 7.9 km/sec.

  10. The canopy interception-landslide initiation conundrum: insight from a tropical secondary forest in northern Thailand

    Science.gov (United States)

    Sidle, Roy C.; Ziegler, Alan D.

    2017-01-01

    The interception and smoothing effect of forest canopies on pulses of incident rainfall and its delivery to the soil has been suggested as a factor in moderating peak pore water pressure in soil mantles, thus reducing the risk of shallow landslides. Here we provide 3 years of rainfall and throughfall data in a tropical secondary dipterocarp forest characterized by few large trees in northern Thailand, along with selected soil moisture dynamics, to address this issue. Throughfall was an estimated 88 % of rainfall, varying from 86 to 90 % in individual years. Data from 167 events demonstrate that canopy interception was only weakly associated (via a nonlinear relationship) with total event rainfall, but not significantly correlated with duration, mean intensity, or antecedent 2-day precipitation (API2). Mean interception during small events (≤ 35 mm) was 17 % (n = 135 events) compared with only 7 % for large events (> 35 mm; n = 32). Examining small temporal intervals within the largest and highest intensity events that would potentially trigger landslides revealed complex patterns of interception. The tropical forest canopy had little smoothing effect on incident rainfall during the largest events. During events with high peak intensities, high wind speeds, and/or moderate-to-high pre-event wetting, measured throughfall was occasionally higher than rainfall during large event peaks, demonstrating limited buffering. However, in events with little wetting and low-to-moderate wind speed, early event rainfall peaks were buffered by the canopy. As rainfall continued during most large events, there was little difference between rainfall and throughfall depths. A comparison of both rainfall and throughfall depths to conservative mean intensity-duration thresholds for landslide initiation revealed that throughfall exceeded the threshold in 75 % of the events in which rainfall exceeded the threshold for both wet and dry conditions. Throughfall intensity for the 11 largest

  11. Thinning of young Douglas-fir forests decreases density of northern flying squirrels in the Oregon Cascades

    Science.gov (United States)

    Manning, Tom; Hagar, Joan C.; McComb, Brenda C.

    2012-01-01

    Large-scale commercial thinning of young forests in the Pacific Northwest is currently promoted on public lands to accelerate the development of late-seral forest structure for the benefit of wildlife species such as northern spotted owls (Strix occidentalis caurina) and their prey, including the northern flying squirrel (Glaucomys sabrinus). Attempts to measure the impact of commercial thinning on northern flying squirrels have mostly addressed short-term effects (2–5 years post-thinning) and the few published studies of longer-term results have been contradictory. We measured densities of northern flying squirrels 11–13 years after thinning of young (55–65 years) Douglas-fir forest stands in the Cascade Range of Oregon, as part of the Young Stand Thinning & Diversity Study. The study includes four replicate blocks, each consisting of an unthinned control stand and one stand each of the following thinning treatments: Heavy Thin; Light Thin; and Light Thin with Gaps. Thinning decreased density of northern flying squirrels, and squirrel densities were significantly lower in heavily thinned stands than in more lightly thinned stands. Regression analysis revealed a strong positive relationship of flying squirrel density with density of large (>30 cm diameter) standing dead trees and a negative relationship with percent cover of low understory shrubs. Maintaining sufficient area and connectivity of dense, closed canopy forest is recommended as a strategy to assure that long-term goals of promoting late-seral structure do not conflict with short-term habitat requirements of this important species.

  12. Climatically induced interannual variability in aboveground production in forest-tundra and northern taiga of central Siberia.

    Science.gov (United States)

    Knorre, Anastasia A; Kirdyanov, Alexander V; Vaganov, Eugene A

    2006-02-01

    To investigate the variability of primary production of boreal forest ecosystems under the current climatic changes, we compared the dynamics of annual increments and productivity of the main components of plant community (trees, shrubs, mosses) at three sites in the north of Siberia (Russia). Annual radial growth of trees and shrubs was mostly defined by summer temperature regime (positive correlation), but climatic response of woody plants was species specific and depends on local conditions. Dynamics of annual increments of mosses were opposite to tree growth. The difference in climatic response of the different vegetation components of the forest ecosystems indicates that these components seem to be adapted to use climatic conditions during the short and severe northern summer, and decreasing in annual production of one component is usually combined with the increase of other component productivity. Average productivity in the northern forest ecosystems varies from 0.05 to 0.14 t ha(-1) year(-1) for trees, from 0.05 to 0.18 t ha(-1) year(-1) for shrubs and from 0.54 to 0.66 t ha(-1) year(-1) for mosses. Higher values of tree productivity combined with lower annual moss productivity were found in sites in northern taiga in comparison with forest-tundra. Different tendencies in the productivity of the dominant species from each vegetation level (trees, shrubs, mosses) were indicated for the last 10 years studied (1990-1999): while productivity of mosses is increasing, productivity of trees is decreasing, but there is no obvious trend in the productivity of shrubs. Our results show that in the long term, the main contribution to changes in annual biomass productivity in forest-tundra and northern taiga ecosystems under the predicted climatic changes will be determined by living ground cover.

  13. Coronado National Forest Draft Land and Resource Management Plan: Cochise, Graham, Pima, Pinal, and Santa Cruz Counties, Arizona, and Hidalgo County, New Mexico

    Science.gov (United States)

    Terry Austin; Yolynda Begay; Sharon Biedenbender; Rachael Biggs; Erin Boyle; Eli Curiel; Sarah Davis; Sara Dechter; Tami Emmett; Mary Farrell; Richard Gerhart; William Gillespie; Polly Haessig; Ed Holloway; Melissa Jenkins; Larry Jones; Debby Kriegel; Robert Lefevre; Mark Stamer; Mindi Lehew; Ann Lynch; George McKay; Linda Peery; Albert Peralta; Jennifer Ruyle; Jeremy Sautter; Kenna Schoenle; Salek Shafiqullah; Christopher Stetson; Mindi Sue Vogel; Laura White; Craig Wilcox; Judy York

    2013-01-01

    The Coronado National Forest is an administrative component of the National Forest System. It administers 1,783,639 acres of National Forest System lands. National forests across the United States were established to provide natural resource-based goods and services to American citizens, and to protect timber and watershed resources. Management of national forests is...

  14. Winds of change: How will windstorms and forest harvesting affect C cycling in northern MN under different climate scenarios?

    Science.gov (United States)

    Lucash, M. S.; Scheller, R. M.; Gustafson, E.; Sturtevant, B.

    2013-12-01

    Forest managers struggle to manage timber resources while integrating the complex interactions that exist among disturbances with the novel conditions produced by a changing climate. To help forest managers better integrate climate change and disturbance projections into their forest management plans, we are using a forest landscape disturbance and succession model (LANDIS-II, Century extension) to project carbon sequestration in northern Minnesota under multiple climate change, management and disturbance scenarios. The model was calibrated and validated using empirical estimates of aboveground productivity and net ecosystem exchange. Our simulations suggest that windstorms will decrease tree biomass and soil organic matter and will increase dead C, resulting in an overall decrease in total C and C sink strength under the GFDL A1FI climate scenario. However the direct effects of climate change on C via altered production and heterotrophic respiration were larger than the impacts of wind. In contrast, forest harvesting will remain the dominant determinant of C dynamics under A1FI, even under management scenarios of more selective logging and longer rotation periods. Recovery from historic (late 1800s and early 1900s) disturbance - clearcut logging and wildfire - remain an important, though declining, driver of long-term C dynamics. Our research results will inform regional planning efforts and help forest managers evaluate the relative importance of disturbances (e.g. wind) and forest harvesting under a changing climate.

  15. Modelling runoff in the northern boreal forest using SLURP with snow ripening and frozen ground

    Science.gov (United States)

    St. Laurent, M. E.; Valeo, C.

    2003-04-01

    Northern Manitoba is rich in water resources and the management of this water resource is affected by the hydrological processes taking place in the primarily Boreal forested, flat landscape of the region. This work provides insight into large-scale hydrological modelling in this area using the SLURP hydrological model while incorporating the effects of ripening snow and frozen ground. SLURP was applied to two large watersheds in northern Manitoba. The Taylor River watershed (800 square-km) and the Burntwood River watershed (7000 square-km) were used as study boundaries for the calibration and validation of the original SLURP model (version 12.2) and a modified version that incorporated frozen ground and ripening snow. Digital Elevation Models were derived with ARC/INFO's TOPOGRID function, and in conjunction with digital land cover data, ASAs and their associated physiographic data were derived using SLURPView. A thorough literature review of boreal forest hydrology provided initial parameter estimates. Daily data from 1984 to 1998 were used to calibrate and verify the original model under a variety of meteorological conditions. Calibration on the Taylor River watershed produced respectable results, and model verification efficiencies over the 15 year period were quite good. Verification performance of the Taylor parameter set on the Burntwood River watershed was not acceptable, but only modifications to the evapotranspiration parameters were required to bring model performance up to acceptable levels. Comparisons between observed and computed hydrographs identified problems with spring snowmelt timing, peak and volume prediction. This may be attributed to a lack of consideration for frozen ground in the model, and the use of the temperature index method for snowmelt. Simulations that incorporated a widely used frozen ground infiltration model into SLURP did not improve model performance. However, when SLURP's snowmelt routine was modified to consider the effects

  16. The impact of forest roads on understory plant diversity in temperate hornbeam-beech forests of Northern Iran.

    Science.gov (United States)

    Deljouei, Azade; Abdi, Ehsan; Marcantonio, Matteo; Majnounian, Baris; Amici, Valerio; Sohrabi, Hormoz

    2017-08-01

    Forest roads alter the biotic and abiotic components of ecosystems, modifying temperature, humidity, wind speed, and light availability that, in turn, cause changes in plant community composition and diversity. We aim at investigating and comparing the diversity of herbaceous species along main and secondary forest roads in a temperate-managed hornbeam-beech forest, north of Iran. Sixteen transects along main and secondary forest roads were established (eight transects along main roads and eight along secondary roads). To eliminate the effect of forest type, all transects were located in Carpinetum-Fagetum forests, the dominant forest type in the study area. The total length of each transect was 200 m (100 m toward up slope and 100 m toward down slope), and plots were established along it at different distances from road edge. The diversity of herbaceous plant species was calculated in each plot using Shannon-Wiener index, species richness, and Pielou's index. The results showed that diversity index decreased when distance from road edge increases. This decreasing trend continued up to 60 m from forest road margin, and after this threshold, the index slightly increased. Depending on the type of road (main or secondary) as well as cut or fill slopes, the area showing a statistical different plant composition and diversity measured through Shannon-Wiener, species richness, and Pielou's index is up to 10 m. The length depth of the road edge effect found in main and secondary forest roads was small, but it could have cumulative effects on forest microclimate and forest-associated biota at the island scale. Forest managers should account for the effect of road buildings on plant communities.

  17. Effects of selection cutting on the forest structure and species diversity of evergreen broad-leaved forest in northern Fujian, southern China

    Institute of Scientific and Technical Information of China (English)

    Qiu Ren-hui; Chen Han; Zhuo Li-xin

    2006-01-01

    The short-term effects of selection cutting of different intensities on the forest structure and species diversity of evergreen broad-leaved forest in northern Fujian Province were investigated and analyzed. The results showed that selection cutting of low and medium intensities caused little variation in the forest structure. After cutting, the dominant species retained their leading status in the community. However, the community structure changed significantly following selection cutting of high and extra-high intensities;the status of the dominant species of the community declined dramatically. Some tree species began to disappear from the sampling plots. Except for extra-high intensity cutting, the diversity of tree species did not change significantly for the other three cutting intensities. However, the evenness of the stands was very different among the four kinds of cutting plots. For low and medium intensity selection cutting, the evenness declined slightly. For extra-high intensity selection cutting, the evenness increased to some extent,which might be due to a more even distribution of tree species after cutting. Cutting operations resulted in some adverse reactions to development of arborous species diversity of evergreen broad-leaved forest, particularly serious damage to the forest canopy. But the rational selection cuttings, which may benefit the restoration and maintenance of species diversity over a long period and may come about from the variations in environmental factors such as sunlight, temperature and humidity.

  18. Holocene forest development and maintenance on different substrates in the Klamath Mountains, northern California, USA.

    Science.gov (United States)

    Briles, Christy E; Whitlock, Cathy; Skinner, Carl N; Mohr, Jerry

    2011-03-01

    The influence of substrate on long-term vegetation dynamics has received little attention, and yet nutrient-limited ecosystems have some of the highest levels of endemism in the world. The diverse geology of the Klamath Mountains of northern California (USA) allows examination of the long-term influence of edaphic constraints in subalpine forests through a comparison of vegetation histories between nutrient-limited ultramafic substrates and terrain that is more fertile. Pollen and charcoal records spanning up to 15000 years from ultramafic settings reveal a distinctly different vegetation history compared to other soil types. In non-ultramafic settings, the dominant trees and shrubs shifted in elevation in response to Holocene climate variations resulting in compositional and structural changes, whereas on ultramafic substrates changes were primarily structural, not compositional. Fire activity was similar through most of the Holocene with the exception of declines over the last 4000 years on ultramafic substrates, likely due to the reduction of understory fuels and cooler wetter conditions than in the middle Holocene. These results suggest that the tree and shrub distributions were more responsive to past climate changes on non-ultramafic substrates compared to those on ultramafic substrates. The combination of these dynamics may help explain high levels of plant diversity in the Klamath Mountains and provide insights for managing these complex ecosystems.

  19. Slope gradient and shape effects on soil profiles in the northern mountainous forests of Iran

    Science.gov (United States)

    Fazlollahi Mohammadi, M.; Jalali, S. G. H.; Kooch, Y.; Said-Pullicino, D.

    2016-12-01

    In order to evaluate the variability of the soil profiles at two shapes (concave and convex) and five positions (summit, shoulder, back slope, footslope and toeslope) of a slope, a study of a virgin area was made in a Beech stand of mountain forests, northern Iran. Across the slope positions, the soil profiles demonstrated significant changes due to topography for two shape slopes. The solum depth of the convex slope was higher than the concave one in all five positions, and it decreased from the summit to shoulder and increased from the mid to lower slope positions for both convex and concave slopes. The thin solum at the upper positions and concave slope demonstrated that pedogenetic development is least at upper slope positions and concave slope where leaching and biomass productivity are less than at lower slopes and concave slope. A large decrease in the thickness of O and A horizons from the summit to back slope was noted for both concave and convex slopes, but it increased from back slope toward down slope for both of them. The average thickness of B horizons increased from summit to down slopes in the case of the concave slope, but in the case of convex slope it decreased from summit to shoulder and afterwards it increased to the down slope. The thicknesses of the different horizons varied in part in the different positions and shape slopes because they had different plant species cover and soil features, which were related to topography.

  20. Attitudes Towards Forest Elephant Conservation Around a Protected Area in Northern Congo

    Directory of Open Access Journals (Sweden)

    Félicien Nsonsi

    2017-01-01

    Full Text Available An assessment of local attitudes towards conservation can guide wildlife managers in the effective application of measurements to improve these perceptions. Here we conducted a quantitative questionnaire survey around a protected area in northern Congo surveying 314 households living in four villages around the Nouabalé-Ndoki National Park. We investigated the impact of the benefits of a conservation project (led by an international non-governmental organisation, the experience with human-elephant conflict and the respondents' socio-economic profile on local people's attitudes towards forest elephant conservation. Using multivariate analysis, we found overall positive attitudes towards elephant conservation with more positive answers in the village where a conservation project is based. Furthermore, people employed in the conservation project stated more positive attitudes compared to logging company employees famers, natural resource users and people conducting other jobs. Experience of human elephant conflict negatively impacted people's perceptions. Socio-economic variables, such as ethnic group, education level or salary category had relatively little impact on people's responses. Qualitative statements largely supported the questionnaire results. We discuss our results in the light of the limits of attitude surveys and suggest further investigations to identify the activities needed to foster positive attitudes for elephant conservation in all villages around the Nouabalé-Ndoki National Park in partnership with the logging company.

  1. The Use of Ecological Indicators as a Basis for Operationalizing a PES Scheme on Forest Conservation in Northern Argentina

    Science.gov (United States)

    Gobbi, José; Deguillon, Marie

    2017-04-01

    Payments for ecosystem services (PES) aim to improve the supply of ecosystem services (ES) by making payments to service providers, which are conditional on the provision of those services. Payments cannot be conditional unless the service can be effectively monitored. Direct monitoring of ES to assess conditionality could be methodologically complex and operatively expensive. To overcome such constraints, the pilot "GEF-PES Project" of Northern Argentina has developed a set of five indicators on forest conservation status (CS) as a basis for estimating the amount of ES provided -considering a positive correlation between the CS of a forest and its level of provision of ecosystem services -and for operationalizing the PES. Field data indicate that selected indicators: (i) exhibit strong correlation with the amount of carbon and biodiversity provided by forests according to their CS, ii) are cost-effective to monitor ES conditionality and (iii) allow easy application of payment levels.

  2. Interglacial genetic diversification of Moussonia deppeana (Gesneriaceae), a hummingbird-pollinated, cloud forest shrub in northern Mesoamerica.

    Science.gov (United States)

    Ornelas, Juan Francisco; González, Clementina

    2014-08-01

    Recent empirical work on cloud forest-adapted species supports the role of both old divergences across major geographical areas and more recent divergences attributed to Pleistocene climate changes. The shrub Moussonia deppeana is distributed in northern Mesoamerica, with geographically disjunct populations. Based on sampling throughout the species range and employing plastid and nuclear markers, we (i) test whether the fragmented distribution is correlated with main evolutionary lineages, (ii) reconstruct its phylogeographical history to infer the history of cloud forest in northern Mesoamerica and (iii) evaluate a set of refugia/vicariance scenarios for the region and demographic patterns of the populations whose ranges expanded and tracked cloud forest conditions during the Last Glacial Maximum. We found a deep evolutionary split in M. deppeana about 6-3 Ma, which could be consistent with a Pliocene divergence. Comparison of variation in plastid and nuclear markers revealed several lineages mostly congruent with their isolated geographical distribution and restricted gene flow among groups. Results of species distribution modelling and coalescent simulations fit a model of multiple refugia diverging during interglacial cycles. The demographic history of M. deppeana is not consistent with an expanding-contracting cloud forest archipelago model during the Last Glacial Maximum. Instead, our data suggest that populations persisted across the geographical range throughout the glacial cycles, and experienced isolation and divergence during interglacial periods. © 2014 John Wiley & Sons Ltd.

  3. Ecoregions of Arizona (poster)

    Science.gov (United States)

    Griffith, Glenn E.; Omernik, James M.; Johnson, Colleen Burch; Turner, Dale S.

    2014-01-01

    Ecoregions denote areas of general similarity in ecosystems and in the type, quality, and quantity of environmental resources; they are designed to serve as a spatial framework for the research, assessment, management, and monitoring of ecosystems and ecosystem components. By recognizing the spatial differences in the capacities and potentials of ecosystems, ecoregions stratify the environment by its probable response to disturbance. These general purpose regions are critical for structuring and implementing ecosystem management strategies across federal agencies, state agencies, and nongovernment organizations that are responsible for different types of resources within the same geographical areas. The Arizona ecoregion map was compiled at a scale of 1:250,000. It revises and subdivides an earlier national ecoregion map that was originally compiled at a smaller scale. The approach used to compile this map is based on the premise that ecological regions can be identified through the analysis of the spatial patterns and the composition of biotic and abiotic phenomena that affect or reflect differences in ecosystem quality and integrity. These phenomena include geology, physiography, vegetation, climate, soils, land use, wildlife, and hydrology. The relative importance of each characteristic varies from one ecological region to another regardless of the hierarchical level. A Roman numeral hierarchical scheme has been adopted for different levels of ecological regions. Level I is the coarsest level, dividing North America into 15 ecological regions. Level II divides the continent into 50 regions. At level III, the continental United States contains 105 ecoregions and the conterminous United States has 85 ecoregions. Level IV is a further subdivision of level III ecoregions. Arizona contains arid deserts and canyonlands, semiarid shrub- and grass-covered plains, woodland- and shrubland-covered hills, lava fields and volcanic plateaus, forested mountains, glaciated

  4. Nitrogen immobilization by wood-chip application: Protecting water quality in a northern hardwood forest

    Science.gov (United States)

    Homyak, P.M.; Yanai, R.D.; Burns, Douglas A.; Briggs, R.D.; Germain, R.H.

    2008-01-01

    Forest harvesting disrupts the nitrogen cycle, which may affect stream water quality by increasing nitrate concentrations, reducing pH and acid neutralizing capacity, and mobilizing aluminum and base cations. We tested the application of wood chips derived from logging slash to increase immobilization of N after harvesting, which should reduce nitrate flux to streams. In August 2004, a stand of northern hardwoods was patch-clearcut in the Catskill Mountains, NY, and four replicates of three treatments were implemented in five 0.2-ha cut patches. Wood chips were applied to the soil surface at a rate equivalent to the amount of slash smaller than eight inches in diameter (1?? treatment). A second treatment doubled that rate (2??), and a third treatment received no chips (0??). Additionally, three uncut reference plots were established in nearby forested areas. Ion exchange resin bags and soil KCl-extractions were used to monitor nitrate availability in the upper 5-10 cm of soil approximately every seven weeks, except in winter. Resin bags indicated that the wood chips retained 30% or 42% of the nitrate pulse, while for KCl extracts, the retention rate was 78% or 100% of the difference between 0?? and uncut plots. During the fall following harvest, wood-chip treated plots had resin bag soil nitrate concentrations about 25% of those in 0?? plots (p = 0.0001). In the first growing season after the cut, nitrate concentrations in wood-chip treated plots for KCl extracts were 13% of those in 0?? treatments (p = 0.03) in May and about half those in 0?? treatments (p = 0.01) in July for resin bags. During spring snowmelt, however, nitrate concentrations were high and indistinguishable among treatments, including the uncut reference plots for resin bags and below detection limit for KCl extracts. Wood chips incubated in litterbags had an initial C:N of 125:1, which then decreased to 70:1 after one year of field incubation. These changes in C:N values indicate that the wood

  5. An evaluation of ISOCLS and CLASSY clustering algorithms for forest classification in northern Idaho. [Elk River quadrange of the Clearwater National Forest

    Science.gov (United States)

    Werth, L. F. (Principal Investigator)

    1981-01-01

    Both the iterative self-organizing clustering system (ISOCLS) and the CLASSY algorithms were applied to forest and nonforest classes for one 1:24,000 quadrangle map of northern Idaho and the classification and mapping accuracies were evaluated with 1:30,000 color infrared aerial photography. Confusion matrices for the two clustering algorithms were generated and studied to determine which is most applicable to forest and rangeland inventories in future projects. In an unsupervised mode, ISOCLS requires many trial-and-error runs to find the proper parameters to separate desired information classes. CLASSY tells more in a single run concerning the classes that can be separated, shows more promise for forest stratification than ISOCLS, and shows more promise for consistency. One major drawback to CLASSY is that important forest and range classes that are smaller than a minimum cluster size will be combined with other classes. The algorithm requires so much computer storage that only data sets as small as a quadrangle can be used at one time.

  6. Windows of opportunity: white-tailed deer and the dynamics of northern hardwood forests of the northeastern US

    Science.gov (United States)

    Sage, R.W.; Porter, W.F.; Underwood, H.B.

    2003-01-01

    Herbivory, lighting regimes, and site conditions are among the most important determinants of forest regeneration success, but these are affected by a host of other factors such as weather, predation, human exploitation, pathogens, wind and fire. We draw together > 50 years of research on the Huntington Wildlife Forest in the central Adirondack Mountains of New York to explore regeneration of northern hardwoods. A series of studies each of which focused on a single factor failed to identify the cause of regeneration failure. However, integration of these studies led to broader understanding of the process of forest stand development and identified at least three interacting factors: lighting regime, competing vegetation and selective browsing by white-tailed deer (Odocoileus virginianus). The diverse 100-200 year-old hardwood stands present today probably reflect regeneration during periods of low deer density (< 2.0 deer/km super(2)) and significant forest disturbance. If this hypothesis is correct, forest managers can mimic these 'natural windows of opportunity' through manipulation of a few sensitive variables in the system. Further, these manipulations can be conducted on a relatively small geographic scale. Control of deer densities on a scale of 500 ha and understory American beech (Fagus grandifolia) on a scale of < 100 ha in conjunction with an even-aged regeneration system consistently resulted in successful establishment of desirable hardwood regeneration.

  7. VOLATILE ORGANIC COMPOUND EMISSION RATES FROM MIXED DECIDUOUS AND CONIFEROUS FORESTS IN NORTHERN WISCONSIN, USA

    Science.gov (United States)

    Biogenic emissions of volatile organic compounds (VOC) from forests play an important role in regulating the atmospheric trace gas composition including global tropospheric ozone concentrations. However, more information is needed on VOC emission rates from different forest regio...

  8. Atmospheric removal of PM2.5 by man-made Three Northern Regions Shelter Forest in Northern China estimated using satellite retrieved PM2.5 concentration.

    Science.gov (United States)

    Zhang, Xiaodong; Du, Jiao; Huang, Tao; Zhang, Leiming; Gao, Hong; Zhao, Yuan; Ma, Jianmin

    2017-03-28

    Atmospheric removal of PM2.5 by the Three Northern Regions Shelter Forest (TNRSF) - the so called Green Great Wall (GGW) in northern China through dry deposition process was estimated using a bulk big-leaf model and a vegetation collection model. Decadal trend of PM2.5 dry deposition flux from 1999 to 2010 was calculated from modeled dry deposition velocity and air concentration retrieved from the satellite remote sensing. Dry deposition velocities of PM2.5 calculated using the two deposition models increased in many places of the TNRSF over the last decade due to increasing vegetation coverage of the TNRSF. Both increasing deposition velocity due to forest expansion and PM2.5 atmospheric level contributed to the increasing deposition flux of PM2.5. The highest atmospheric deposition flux of PM2.5 was found in the Central-north region covering Beijing-Tianjin-Hebei area, followed by the Northwestern and the Northeastern regions of the TNRSF. While greater collection of PM2.5 by vegetation was identified in the Northeastern region of the TNRSF due to higher forest coverage over this region, the most significant incline of the PM2.5 atmospheric removal due to vegetation collection was discerned in the Central-north region because of the most rapid increase in the vegetation coverage in this region. A total mass of 2.85×10(7)t PM2.5 was estimated to be removed from the atmosphere through dry deposition process over the TNRSF from 1999 to 2010. The two deposition models simulated similar magnitude and spatial patterns of PM2.5 dry deposition fluxes. Our results suggest that the TNRSF plays a moderate role in PM2.5 uptake, but enhances PM2.5 atmospheric removal by 30% in 2010 than in 1980.

  9. Elevated carbon dioxide and ozone alter productivity and ecosystem carbon content in northern temperate forests.

    Science.gov (United States)

    Talhelm, Alan F; Pregitzer, Kurt S; Kubiske, Mark E; Zak, Donald R; Campany, Courtney E; Burton, Andrew J; Dickson, Richard E; Hendrey, George R; Isebrands, J G; Lewin, Keith F; Nagy, John; Karnosky, David F

    2014-08-01

    Three young northern temperate forest communities in the north-central United States were exposed to factorial combinations of elevated carbon dioxide (CO2 ) and tropospheric ozone (O3 ) for 11 years. Here, we report results from an extensive sampling of plant biomass and soil conducted at the conclusion of the experiment that enabled us to estimate ecosystem carbon (C) content and cumulative net primary productivity (NPP). Elevated CO2 enhanced ecosystem C content by 11%, whereas elevated O3 decreased ecosystem C content by 9%. There was little variation in treatment effects on C content across communities and no meaningful interactions between CO2 and O3 . Treatment effects on ecosystem C content resulted primarily from changes in the near-surface mineral soil and tree C, particularly differences in woody tissues. Excluding the mineral soil, cumulative NPP was a strong predictor of ecosystem C content (r(2) = 0.96). Elevated CO2 enhanced cumulative NPP by 39%, a consequence of a 28% increase in canopy nitrogen (N) content (g N m(-2) ) and a 28% increase in N productivity (NPP/canopy N). In contrast, elevated O3 lowered NPP by 10% because of a 21% decrease in canopy N, but did not impact N productivity. Consequently, as the marginal impact of canopy N on NPP (∆NPP/∆N) decreased through time with further canopy development, the O3 effect on NPP dissipated. Within the mineral soil, there was less C in the top 0.1 m of soil under elevated O3 and less soil C from 0.1 to 0.2 m in depth under elevated CO2 . Overall, these results suggest that elevated CO2 may create a sustained increase in NPP, whereas the long-term effect of elevated O3 on NPP will be smaller than expected. However, changes in soil C are not well-understood and limit our ability to predict changes in ecosystem C content.

  10. Early forest dynamics in stand-replacing fire patches in the northern Sierra Nevada, California, USA

    Science.gov (United States)

    Brandon M. Collins; Gary B. Roller

    2013-01-01

    There is considerable concern over the occurrence of stand-replacing fire in forest types historically associated with low- to moderate-severity fire. The concern is largely over whether contemporary levels of stand-replacing fire are outside the historical range of variability, and what natural forest recovery is in these forest types following stand-replacing fire....

  11. Fuel load modeling from mensuration attributes in temperate forests in northern Mexico

    Science.gov (United States)

    Maricela Morales-Soto; Marín Pompa-Garcia

    2013-01-01

    The study of fuels is an important factor in defining the vulnerability of ecosystems to forest fires. The aim of this study was to model a dead fuel load based on forest mensuration attributes from forest management inventories. A scatter plot analysis was performed and, from explanatory trends between the variables considered, correlation analysis was carried out...

  12. Impact of biomass harvesting on forest soil productivity in the northern Rocky Mountains

    Science.gov (United States)

    Woongsoon Jang; Christopher R. Keyes; Deborah Page-Dumroese

    2015-01-01

    Biomass harvesting extracts an increased amount of organic matter from forest ecosystems over conventional harvesting. Since organic matter plays a critical role in forest productivity, concerns of potential negative long-term impacts of biomass harvesting on forest productivity (i.e., changing nutrient/water cycling, aggravating soil properties, and compaction) have...

  13. Formal institutions, local arrangements and conflicts in Northern Bolivian communities after forest governance reforms

    NARCIS (Netherlands)

    Cano Cardona, W.

    2012-01-01

    In the last decades, community forest management (CFM) has become an alternative to reach important objectives related to forests sustainability and the improvement of forest dwellers’ wellbeing. In many countries the recognition and development of specific CFM models has been closely related to soc

  14. Frost heaving of planted tree seedlings in the boreal forest of northern Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Goulet, France

    2000-07-01

    Frost heaving can be a leading cause of tree seedling mortality in many places in the boreal forest of Northern Sweden. The aim of this investigation was to improve our understanding of frost heaving of planted tree seedlings as related to snow cover, scarification, planting methods and soil types. The thesis is based on a review paper, three field experiments and one laboratory experiment. The experiments focus on different methods to control frost heaving of forest tree seedlings and on a number of factors affecting the extent of frost heaving. The review paper identifies the many aspects of frost heaving of forest tree seedlings and agricultural crops based on an intensive review of the research contributions made during the last century. Even if many investigations have been carried out with the aim to decrease the extent of frost heaving, very little quantitative results are available for tree seedlings. In a field experiment, the choice of planting positions was effective in decreasing frost heaving of planted seedlings following mounding or disc-trenching. Seedlings planted in the depressions were largely affected by frost heaving with a maximal vertical displacement of 5.4 cm while frost heaving did not occur on the top of the mound. On the other hand, the planting time and planting depth had no influence on the extent of frost heaving. In another field experiment the size of the scarified patches was strongly correlated to frost heaving which reached between 7.6 and 11.5 cm in 4 and 8-dm patches compared to between 4.4 and 5.3 in non-scarified soil and in a 1-dm patch. Ground vegetation probably decreases the diurnal temperature variation and the number of freezing-thawing cycles. The duration and magnitude of frost temperatures, the frost hour sum, increased with patch size. The difference between the 8-dm and 1-dm patch increased to 2064 hour-degrees at the end of the winter. In larger patches, the planting depth seemed to be effective in reducing the

  15. Double inequity? The social dimensions of deforestation and forest protection in local communities in Northern Cambodia

    DEFF Research Database (Denmark)

    Pasgaard, Maya; Chea, Lily

    2013-01-01

    In Cambodia, numerous powerful drivers of land-use change threaten the remaining natural for-est and the livelihoods of local communities living on the forest periphery. In an attempt to protect remaining forests, Community Forestry (CF) and Reduced Emissions from Deforestation and Forest...... disproportionately affect the poorest households, which are more reliant on forest products due to less land and more insecure tenure. Meanwhile, the benefits from CF/REDD+ hardly reach these vulnerable households since their access to forest resources is constrained by physical barriers and a lack of resources...... governance, contested tenure arrangements, high agricultural dependency, and power discrepancies, this paper analyzes and critically discusses this ‘double inequity’ of deforestation and forest protection in Cambodia, and recommendations on how to ensure more equitable distribution of costs and benefits...

  16. The longevity of broadleaf deciduous trees in Northern Hemisphere temperate forests: insights from tree-ring series

    Directory of Open Access Journals (Sweden)

    Alfredo eDi Filippo

    2015-05-01

    Full Text Available Understanding the factors controlling the expression of longevity in trees is still an outstanding challenge for tree biologists and forest ecologists. We gathered tree-ring data and literature for broadleaf deciduous (BD temperate trees growing in closed-canopy old-growth forests in the Northern Hemisphere to explore the role of geographic patterns, climate variability, and growth rates on longevity. Our pan-continental analysis, covering 32 species from 12 genera, showed that 300-400 years can be considered a baseline threshold for maximum tree lifespan in many temperate deciduous forests. Maximum age varies greatly in relation to environmental features, even within the same species. Tree longevity is generally promoted by reduced growth rates across large genetic differences and environmental gradients. We argue that slower growth rates, and the associated smaller size, provide trees with an advantage against biotic and abiotic disturbance agents, supporting the idea that size, not age, is the main constraint to tree longevity. The oldest trees were living most of their life in subordinate canopy conditions and/or within primary forests in cool temperate environments and outside major storm tracks. Very old trees are thus characterized by slow growth and often live in forests with harsh site conditions and infrequent disturbance events that kill much of the trees. Temperature inversely controls the expression of longevity in mesophilous species (Fagus spp., but its role in Quercus spp. is more complex and warrants further research in disturbance ecology. Biological, ecological and historical drivers must be considered to understand the constraints imposed to longevity within different forest landscapes.

  17. Modeling Soil Carbon Dynamics in Northern Forests: Effects of Spatial and Temporal Aggregation of Climatic Input Data.

    Science.gov (United States)

    Dalsgaard, Lise; Astrup, Rasmus; Antón-Fernández, Clara; Borgen, Signe Kynding; Breidenbach, Johannes; Lange, Holger; Lehtonen, Aleksi; Liski, Jari

    2016-01-01

    Boreal forests contain 30% of the global forest carbon with the majority residing in soils. While challenging to quantify, soil carbon changes comprise a significant, and potentially increasing, part of the terrestrial carbon cycle. Thus, their estimation is important when designing forest-based climate change mitigation strategies and soil carbon change estimates are required for the reporting of greenhouse gas emissions. Organic matter decomposition varies with climate in complex nonlinear ways, rendering data aggregation nontrivial. Here, we explored the effects of temporal and spatial aggregation of climatic and litter input data on regional estimates of soil organic carbon stocks and changes for upland forests. We used the soil carbon and decomposition model Yasso07 with input from the Norwegian National Forest Inventory (11275 plots, 1960-2012). Estimates were produced at three spatial and three temporal scales. Results showed that a national level average soil carbon stock estimate varied by 10% depending on the applied spatial and temporal scale of aggregation. Higher stocks were found when applying plot-level input compared to country-level input and when long-term climate was used as compared to annual or 5-year mean values. A national level estimate for soil carbon change was similar across spatial scales, but was considerably (60-70%) lower when applying annual or 5-year mean climate compared to long-term mean climate reflecting the recent climatic changes in Norway. This was particularly evident for the forest-dominated districts in the southeastern and central parts of Norway and in the far north. We concluded that the sensitivity of model estimates to spatial aggregation will depend on the region of interest. Further, that using long-term climate averages during periods with strong climatic trends results in large differences in soil carbon estimates. The largest differences in this study were observed in central and northern regions with strongly

  18. Investigation of radioactive cesium transportation from forest canopy to floor by litterfall, stemflow and throughfall in northern Fukushima

    Science.gov (United States)

    Endo, I.; Ohte, N.; Iseda, K.; Tanoi, K.; Hirose, A.; Kobayashi, N. I.; Murakami, M.; Tokuchi, N.; Ohashi, M.

    2015-12-01

    After the Fukushima Daiichi nuclear power plant accident due to Great East Japan Earthquake in March 11th 2011, large areas of forest have been highly contaminated by the radioactive nuclides. Most of the deposited radioactive material to the canopy is then washed out with rainfall or leaf fall due to the tree phenology. There have been studies showing that the amount of 137Cs transportation differs among litter components and water pathways, and was affected by seasonal variations. Thus, to evaluate the amount of 137Cs flux from canopy to forest floor, continuous monitoring of each component (litterfall, throughfall and stemflow) is required. We investigated the annual transfer of 137Cs from the forest canopy to the floor by litterfall, throughfall and stemflow at two different forest types in northern Fukushima after two years from the accident. Seasonal variations in 137Cs transportation and differences between forests types were also determined. Forest sites were set in the upstream part of Kami-Oguni River catchment at Date city, which locates approximately 50km northwest from the Fukushima Dai-ichi Nuclear Power Plant. The study sites consisted of two deciduous (Mixed deciduous-1, Mixed deciduous-2) and one cedar (Cedar plantation) stands. The cumulative 137Cs transportation from the forest canopy to the floor was 6.6 kBq m-2 year-1 for the Mixed deciduous-1, 3.9 kBq m-2 year-1 for the Mixed deciduous-2 and 11.0 kBq m-2 year-1 for the Cedar plantation. 137Cs transportation with litterfall increased in the defoliation period which correlated with the increased amount of litterfall. 137Cs transportation with throughfall and stemflow increased in the rainy season. 137Cs flux by litterfall was higher in Cedar plantation compared with that of mixed deciduous forests, while the opposite result was obtained for stemflow. The ratio of annual 137Cs flux and the estimated 137Cs amount deposited in the forests will be discussed.

  19. Hydrologic connectivity of floodplains, northern Missouri: implications for management and restoration of floodplain forest communities in disturbed landscapes

    Science.gov (United States)

    Jacobson, R.; Faust, T.

    2014-01-01

    Hydrologic connectivity between the channel and floodplain is thought to be a dominant factor determining floodplain processes and characteristics of floodplain forests. We explored the role of hydrologic connectivity in explaining floodplain forest community composition along streams in northern Missouri, USA. Hydrologic analyses at 20 streamgages (207–5827 km2 area) document that magnitudes of 2-year return floods increase systematically with increasing drainage area whereas the average annual number and durations of floodplain-connecting events decrease. Flow durations above the active-channel shelf vary little with increasing drainage area, indicating that the active-channel shelf is in quasi-equilibrium with prevailing conditions. The downstream decrease in connectivity is associated with downstream increase in channel incision. These relations at streamflow gaging stations are consistent with regional channel disturbance patterns: channel incision increases downstream, whereas upstream reaches have either not incised or adjusted to incision by forming new equilibrium floodplains. These results provide a framework to explain landscape-scale variations in composition of floodplain forest communities in northern Missouri. Faust () had tentatively explained increases of flood-dependent tree species, and decreases of species diversity, with a downstream increase in flood magnitude and duration. Because frequency and duration of floodplain-connecting events do not increase downstream, we hypothesize instead that increases in relative abundance of flood-dependent trees at larger drainage area result from increasing size of disturbance patches. Bank-overtopping floods at larger drainage area create large, open, depositional landforms that promoted the regeneration of shade-intolerant species. Higher tree species diversity in floodplains with small drainage areas is associated with non-incised floodplains that are frequently connected to their channels and

  20. Long-term changes in forest carbon under temperature and nitrogen amendments in a temperate northern hardwood forest.

    Science.gov (United States)

    Savage, Kathleen E; Parton, William J; Davidson, Eric A; Trumbore, Susan E; Frey, Serita D

    2013-08-01

    Currently, forests in the northeastern United States are net sinks of atmospheric carbon. Under future climate change scenarios, the combined effects of climate change and nitrogen deposition on soil decomposition, aboveground processes, and the forest carbon balance remain unclear. We applied carbon stock, flux, and isotope data from field studies at the Harvard forest, Massachusetts, to the ForCent model, which integrates above- and belowground processes. The model was able to represent decadal-scale measurements in soil C stocks, mean residence times, fluxes, and responses to a warming and N addition experiment. The calibrated model then simulated the longer term impacts of warming and N deposition on the distribution of forest carbon stocks. For simulation to 2030, soil warming resulted in a loss of soil organic matter (SOM), decreased allocation to belowground biomass, and gain of aboveground carbon, primarily in large wood, with an overall small gain in total system carbon. Simulated nitrogen addition resulted in a small increase in belowground carbon pools, but a large increase in aboveground large wood pools, resulting in a substantial increase in total system carbon. Combined warming and nitrogen addition simulations showed a net gain in total system carbon, predominately in the aboveground carbon pools, but offset somewhat by losses in SOM. Hence, the impact of continuation of anthropogenic N deposition on the hardwood forests of the northeastern United States may exceed the impact of warming in terms of total ecosystem carbon stocks. However, it should be cautioned that these simulations do not include some climate-related processes, different responses from changing tree species composition. Despite uncertainties, this effort is among the first to use decadal-scale observations of soil carbon dynamics and results of multifactor manipulations to calibrate a model that can project integrated aboveground and belowground responses to nitrogen and climate

  1. Restoring the Nitrogen Cycle in the Boreal Forest - a Case Study from Northern Alberta

    Science.gov (United States)

    Masse, Jacynthe; Grayston, Sue; Prescott, Cindy; Quideau, Sylvie

    2014-05-01

    The Athabasca oil sands deposit, located in the boreal forests of Northern Alberta, is one of the largest single oil deposits in the world. This deposit rests underneath 40,200 square kilometres of land. To date, an area of about 715 square kilometres has been disturbed by oil sands mining activity (Government of Alberta, 2013). Following surface mining, companies have the legal obligation to restore soil-like profiles that can support the previous land capabilities (Powter et al., 2012). Because of its importance for site productivity, re-establishment of the nitrogen cycle between these reconstructed soils and plants is one of the most critical factors required to insure long term sustainability of reclaimed boreal landscape. High nitrogen deposition recorded in the oil sands area combined with the high level of nitrate found in reclaimed soils raised concerns about the possibility of these reclaimed soils being in early stages of N saturation (Laxton et al 2010; Hemsley, 2012), although little evidence of net nitrification in these reclaimed soils suggests the contrary (Laxton et al. 2012). To date, results on the behaviour of the nitrogen cycle in the reclaimed sites are contradictory. A systematic study of the nitrogen cycle, and especially rates of gross mineralization, nitrification and denitrification, is needed. Our research aimed at 1) measuring the gross rates of nitrogen transformations under different vegetation treatments in both reclaimed and naturally-disturbed (fire) sites and 2) characterizing the microbial communities participating in the nitrogen cycle within the same soils. A series of 20 soils, covering different vegetation treatments (plots planted with aspen (Populus tremuloides), spruce (Picea glauca) and grassland) were investigated. Gross nitrogen transformation rates were measured using 15N pool-dilution (Müller et al. 2007). Microbial communities participating in the N-cycle were characterized using qPCR and pyrosequencing. Differences

  2. Holocene evolution of lakes in the forest-tundra biome of northern Manitoba, Canada

    Science.gov (United States)

    Hobbs, William O.; Edlund, Mark B.; Umbanhowar, Charles E.; Camill, Philip; Lynch, Jason A.; Geiss, Christoph; Stefanova, Vania

    2017-03-01

    The late-Quaternary paleoenvironmental history of the western Hudson Bay region of Subarctic Canada is poorly constrained. Here, we present a regional overview of the post-glacial history of eight lakes which span the forest-tundra biome in northern Manitoba. We show that during the penultimate drainage phase of Lake Agassiz the lake water had an estimated pH of ∼6.0, with abundant quillwort (Isöetes spp.) along the lakeshore and littoral zone and some floating green algae (Botryococcus spp. and Pediastrum sp.). Based on multiple sediment proxies, modern lake ontogeny in the region commenced at ∼7500 cal yrs BP. Pioneering diatom communities were shaped by the turbid, higher alkalinity lake waters which were influenced by base cation weathering of the surrounding till following Lake Agassiz drainage. By ∼7000 cal yrs BP, soil development and Picea spp. establish and the lakes began a slow trajectory of acidification over the remaining Holocene epoch. The natural acidification of the lakes in this region is slow, on the order of several millennia for one pH unit. Each of the study lakes exhibit relatively stable aquatic communities during the Holocene Thermal Maximum, suggesting this period is a poor analogue for modern climatic changes. During the Neoglacial, the beginning of the post-Little Ice Age period represents the most significant climatic event to impact the lakes of N. Manitoba. In the context of regional lake histories, the rate of diatom floristic change in the last 200-300 years is unprecedented, with the exception of post-glacial lake ontogeny in some of the lakes. For nearly the entire history of the lakes in this region, there is a strong linkage between landscape development and the aquatic ecosystems; however this relationship appears to become decoupled or less strong in the post-LIA period. Significant 20th century changes in the aquatic ecosystem cannot be explained wholly by changes in the terrestrial ecosystem, suggesting that future

  3. Soil CO2 efflux of a larch forest in northern Japan

    Directory of Open Access Journals (Sweden)

    Y. Fujinuma

    2010-11-01

    Full Text Available We had continuously measured soil CO2 efflux (Rs in a larch forest in northern Japan at hourly intervals for the snow-free period in 2003 with an automated chamber system and partitioned Rs into heterotrophic respiration (Rh and autotrophic respiration (Rr by using the trench method. In addition, we applied the soil CO2 concentration gradients method to continuously measure soil CO2 profiles under snowpack in the snowy period and to partition Rs into topsoil (Oa and A horizons CO2 efflux (Ft with a depth of 0.13 m and sub-soil (C horizon CO2 efflux (Fc. We found that soil CO2 effluxes were strongly affected by the seasonal variation of soil temperature but weakly correlated with soil moisture, probably because the volumetric soil moisture (30–40% at 95% confidence interval was within a plateau region for root and microbial activities. The soil CO2 effluxes changed seasonally in parallel with soil temperature in topsoil with the peak in late summer. On the other hand, the contribution of Rr to Rs was the largest at about 50% in early summer, when canopy photosynthesis and plant growth were more active. The temperature sensitivity (Q10 of Rr peaked in June. Under snowpack, Rs was stable until mid-March and then gradually increased with snow melting. Rs summed up to 79 gC m−2 during the snowy season for 4 months. The annual Rs was determined at 934 gC m−2 y−1 in 2003, which accounted for 63% of ecosystem respiration. The annual contributions of Rh and Rs to Rs were 57% and 43%, respectively. Based on the gradient approach, Rs was partitioned vertically into litter (Oi and Oe horizons with a depth of 0.01–0.02 m, topsoil and sub-soil respirations with proportions of 6, 72 and 22%, respectively, on an annual basis. The vertical distribution of CO2 efflux was consistent with those of soil carbon and root biomass.

  4. Elevated carbon dioxide and ozone alter productivity and ecosystem carbon content in northern temperate forests

    Science.gov (United States)

    Talhelm, Alan F; Pregitzer, Kurt S; Kubiske, Mark E; Zak, Donald R; Campany, Courtney E; Burton, Andrew J; Dickson, Richard E; Hendrey, George R; Isebrands, J G; Lewin, Keith F; Nagy, John; Karnosky, David F

    2014-01-01

    Three young northern temperate forest communities in the north-central United States were exposed to factorial combinations of elevated carbon dioxide (CO2) and tropospheric ozone (O3) for 11 years. Here, we report results from an extensive sampling of plant biomass and soil conducted at the conclusion of the experiment that enabled us to estimate ecosystem carbon (C) content and cumulative net primary productivity (NPP). Elevated CO2 enhanced ecosystem C content by 11%, whereas elevated O3 decreased ecosystem C content by 9%. There was little variation in treatment effects on C content across communities and no meaningful interactions between CO2 and O3. Treatment effects on ecosystem C content resulted primarily from changes in the near-surface mineral soil and tree C, particularly differences in woody tissues. Excluding the mineral soil, cumulative NPP was a strong predictor of ecosystem C content (r2 = 0.96). Elevated CO2 enhanced cumulative NPP by 39%, a consequence of a 28% increase in canopy nitrogen (N) content (g N m−2) and a 28% increase in N productivity (NPP/canopy N). In contrast, elevated O3 lowered NPP by 10% because of a 21% decrease in canopy N, but did not impact N productivity. Consequently, as the marginal impact of canopy N on NPP (ΔNPP/ΔN) decreased through time with further canopy development, the O3 effect on NPP dissipated. Within the mineral soil, there was less C in the top 0.1 m of soil under elevated O3 and less soil C from 0.1 to 0.2 m in depth under elevated CO2. Overall, these results suggest that elevated CO2 may create a sustained increase in NPP, whereas the long-term effect of elevated O3 on NPP will be smaller than expected. However, changes in soil C are not well-understood and limit our ability to predict changes in ecosystem C content. PMID:24604779

  5. Changes in community perspectives on the roles and rules of church forests in northern Ethiopia: evidence from a panel survey of four Ethiopian Orthodox communities

    Directory of Open Access Journals (Sweden)

    Travis William Reynolds

    2017-04-01

    Full Text Available Some of the only Afromontane forest in northern Ethiopia today is on lands managed by followers of the Ethiopian Orthodox Church, where for centuries priests and communities have conserved forest groves around church buildings. The ecological value of the thousands of church forests in Ethiopia has been widely acknowledged, but little is known about the diverse local institutions that govern these resources, or how such institutions might be changing in response to Ethiopia’s rapid recent economic development. This study uses a unique panel survey to explore changes in community perspectives on the social and ecological roles of church forests, and rules governing church forest use, in four Orthodox communities over time. Our sample consists of 122 household surveys conducted in 2002 and a further 122 surveys from 2014, with 71 households interviewed in both periods. We find that reported uses of church forests vary across forests and over time, with larger forests more likely to be used for extractive purposes such as firewood and construction timber, while smaller forests have become more restricted to renewable or non-extractive uses such as natural medicines, honey, and prayer. Results of logistic regression suggest church followers’ support for preserving church forests increases with age and access to alternative sources of firewood – including exotic Eucalyptus spp. plantations which are increasingly widespread in northern Ethiopia. We also observe a shift since 2002 away from an expectation that church followers themselves hold responsibility for rule enforcement in church forests to a perceived sharing of responsibility by church authorities (i.e. priests and government (i.e. police in 2014. Together the progressive introduction of exotic tree species in church forests combined with the erosion of religious norms surrounding local forest governance may threaten the integrity and diversity of these unique social-ecological systems.

  6. Ground-Water Flow Model of the Sierra Vista Subwatershed and Sonoran Portions of the Upper San Pedro Basin, Southeastern Arizona, United States, and Northern Sonora, Mexico

    Science.gov (United States)

    Pool, D.R.; Dickinson, Jesse E.

    2007-01-01

    A numerical ground-water model was developed to simulate seasonal and long-term variations in ground-water flow in the Sierra Vista subwatershed, Arizona, United States, and Sonora, Mexico, portions of the Upper San Pedro Basin. This model includes the simulation of details of the groundwater flow system that were not simulated by previous models, such as ground-water flow in the sedimentary rocks that surround and underlie the alluvial basin deposits, withdrawals for dewatering purposes at the Tombstone mine, discharge to springs in the Huachuca Mountains, thick low-permeability intervals of silt and clay that separate the ground-water flow system into deep-confined and shallow-unconfined systems, ephemeral-channel recharge, and seasonal variations in ground-water discharge by wells and evapotranspiration. Steady-state and transient conditions during 1902-2003 were simulated by using a five-layer numerical ground- water flow model representing multiple hydrogeologic units. Hydraulic properties of model layers, streamflow, and evapotranspiration rates were estimated as part of the calibration process by using observed water levels, vertical hydraulic gradients, streamflow, and estimated evapotranspiration rates as constraints. Simulations approximate observed water-level trends throughout most of the model area and streamflow trends at the Charleston streamflow-gaging station on the San Pedro River. Differences in observed and simulated water levels, streamflow, and evapotranspiration could be reduced through simulation of climate-related variations in recharge rates and recharge from flood-flow infiltration.

  7. Traditional silvopastoral management and its effects on forest stand structure in northern Zagros, Iran

    DEFF Research Database (Denmark)

    Valipour, Ahmad; Plieninger, Tobias; Shakeri, Zahed

    2014-01-01

    Oak forests of Iran are managed for soil conservation, water quality and other non-market ecosystem services. Nationalization policies in 1963 implied shifts from private ownership and informal traditional management to public ownership and state forest management. In spite of the nationalization...

  8. The dynamic history of the upper forest line ecotone in the northern Andes

    NARCIS (Netherlands)

    Hooghiemstra, H.; Berrio, J.C.; Groot, M.H.M.; Bogotá-A, R.G.; Moscol Olivera, M.; González-Carranza, Z.; Myster, R.W.

    2012-01-01

    In the Andean cordilleras very conspicuous ecotones can be found. The transition from continuous upper montane forest to treeless herbaceous vegetation, regionally known as "páramo" (Cleef 1981; Luteyn 1999) is known as the "upper forest line" (UFL) or "timber line" (Holtmeier 2009). Above the UFL t

  9. Traditional silvopastoral management and its effects on forest stand structure in northern Zagros, Iran

    DEFF Research Database (Denmark)

    Valipour, Ahmad; Plieninger, Tobias; Shakeri, Zahed

    2014-01-01

    Oak forests of Iran are managed for soil conservation, water quality and other non-market ecosystem services. Nationalization policies in 1963 implied shifts from private ownership and informal traditional management to public ownership and state forest management. In spite of the nationalization...

  10. Sixty Years of Silviculture in a Northern Conifer Forest in Maine, USA

    Science.gov (United States)

    Nicole Rogers; Laura Kenefic; Mindy Crandall; Robert Seymour; Paul Sendak

    2017-01-01

    In 1950, the US Forest Service initiated a cutting practice level (CPL) study on the Penobscot Experimental Forest in Maine on the basis of findings of a national appraisal of forestland management. Silvicultural treatments, including the selection system with 5- and 15-year cutting cycles, fixed diameter-limit cutting, and variants of commercial clearcutting, were...

  11. Elevation dependent sensitivity of northern hardwoods to Ca addition at Hubbard Brook Experimental Forest, NH USA

    Science.gov (United States)

    Rakesh Minocha; Stephanie Long; Palaniswamy Thangavel; Subhash C. Minocha; Christopher Eagar; Charles T. Driscoll

    2010-01-01

    Acidic deposition has caused a depletion of calcium (Ca) in the northeastern forest soils. Wollastonite (Ca silicate) was added to watershed 1 (WS1) at the Hubbard Brook Experimental Forest (HBEF) in 1999 to evaluate its effects on various functions of the HBEF ecosystem. The effects of Ca addition on foliar soluble (extractable in 5% HClO4) ions...

  12. Production rates for United States Forest Service brush disposal planning in the northern Rocky Mountains

    Science.gov (United States)

    Dan Loeffler; Stu Hoyt; Nathaniel Anderson

    2017-01-01

    Timber harvesting operations generate brush and other vegetative debris, which often has no marketable value. In many western U.S. forests, these materials represent a fire hazard and a potential threat to forest health and must be removed or burned for disposal. Currently, there is no established, consistent method to estimate brush disposal production rates in the U....

  13. Double inequity? The social dimensions of deforestation and forest protection in local communities in Northern Cambodia

    DEFF Research Database (Denmark)

    Pasgaard, Maya; Chea, Lily

    2013-01-01

    disproportionately affect the poorest households, which are more reliant on forest products due to less land and more insecure tenure. Meanwhile, the benefits from CF/REDD+ hardly reach these vulnerable households since their access to forest resources is constrained by physical barriers and a lack of resources...... or information. Their ability to enjoy benefits from forest protection is likewise limited by social exclusion facilitated by prevailing power structures. Instead, benefits are biased towards the better-off households who engage in forest protection activities and decision-making. In the context of weak...... governance, contested tenure arrangements, high agricultural dependency, and power discrepancies, this paper analyzes and critically discusses this ‘double inequity’ of deforestation and forest protection in Cambodia, and recommendations on how to ensure more equitable distribution of costs and benefits...

  14. Quantifying Live Aboveground Biomass and Forest Disturbance of Mountainous Natural and Plantation Forests in Northern Guangdong, China, Based on Multi-Temporal Landsat, PALSAR and Field Plot Data

    Directory of Open Access Journals (Sweden)

    Wenjuan Shen

    2016-07-01

    Full Text Available Spatially explicit knowledge of aboveground biomass (AGB in large areas is important for accurate carbon accounting and quantifying the effect of forest disturbance on the terrestrial carbon cycle. We estimated AGB from 1990 to 2011 in northern Guangdong, China, based on a spatially explicit dataset derived from six years of national forest inventory (NFI plots, Landsat time series imagery (1986–2011 and Advanced Land Observing Satellite (ALOS Phased Array L-band Synthetic Aperture Radars (PALSAR 25 m mosaic data (2007–2010. Four types of variables were derived for modeling and assessment. The random forest approach was used to seek the optimal variables for mapping and validation. The root mean square error (RMSE of plot-level validation was between 6.44 and 39.49 (t/ha, the normalized root-mean-square error (NRMSE was between 7.49% and 19.01% and mean absolute error (MAE was between 5.06 and 23.84 t/ha. The highest coefficient of determination R2 of 0.8 and the lowest NRMSE of 7.49% were reported in 2006. A clear increasing trend of mean AGB from the lowest value of 13.58 t/ha to the highest value of 66.25 t/ha was witnessed between 1988 and 2000, while after 2000 there was a fluctuating ascending change, with a peak mean AGB of 67.13 t/ha in 2004. By integrating AGB change with forest disturbance, the trend in disturbance area closely corresponded with the trend in AGB decrease. To determine the driving forces of these changes, the correlation analysis was adopted and exploratory factor analysis (EFA method was used to find a factor rotation that maximizes this variance and represents the dominant factors of nine climate elements and nine human activities elements affecting the AGB dynamics. Overall, human activities contributed more to short-term AGB dynamics than climate data. Harvesting and human-induced fire in combination with rock desertification and global warming made a strong contribution to AGB changes. This study provides

  15. Development of integrated forest management/harvesting plans for biomass supply operations in remote northern community settings

    Energy Technology Data Exchange (ETDEWEB)

    VanEvery, K.C.; Higgelke, P.

    2000-07-01

    The use of district heating and mini-district heating systems are attractive options for remote Aboriginal communities. Biomass district heating combines new technology with a traditional source of energy. The systems usually consist of a biomass-fuelled central furnace/boiler system and a network of insulated pipes. The boiler heats water, which is distributed to several buildings connected to the system. The heated water, which is used for space heating, recirculates to the central furnace where it is reheated. The system is also used to produce potable hot water. A mini-district heating system can work well for communities looking to heat clusters of buildings such as schools, residences, and any other buildings. The advantages of biomass burning systems include cost savings, employment generation, improved retention of community funds, enhanced community self-reliance, decreased potential for fuel spills, reduced net-gain in air pollution because the heating systems are carbon neutral, reduced household fire hazard, and a readily available source of natural resources. The Ouje-Bougoumou Cree Nation in northern Quebec and Grassy Narrows First Nation in northern Ontario have both provided examples of successful construction and operation of biomass-fuelled heating systems for their communities. The source of biomass for both communities is wood fibre waste produced by nearby sawmills. This paper presented a basic description of the components needed in developing an Integrated Forest Management and Biomass-Harvesting Plan for remote communities. It is based on an Integrated Forest Management Harvesting Plan completed for Eabametoong First Nation in northern Ontario which was looking into biomass as an alternative heating source. The paper also provided a summary of the considerations that should be examined for the development of small-scale Integrated Forest Management Harvesting Plan for wood biomass production. These considerations include community

  16. Effects of Holocene vegetation change on soils across the forest-grassland transition, northern Minnesota, and implications for erosion processes

    Science.gov (United States)

    Mason, Joseph; Kasmerchak, Chase; Keita, Hawa; Liang, Mengyu; Gruley, Kristine

    2016-04-01

    Boundaries between forest and grassland in the midlatitudes and their shifts in response to Holocene climatic change, provide opportunities to detect effects of life on landscapes. In northern Minnesota, USA, paleoecological research has documented that grassland and/or savanna expanded eastward in the dry early to middle Holocene. In the late Holocene, forest cover expanded westward at the expense of savanna and grassland. We studied soils at 20 sites spanning the forest-grassland transition. A dramatic change in soil morphology coincides approximately, though not exactly, with that transition as recorded in 1870s-1880s land surveys, suggesting that soils change rapidly in response to forest expansion (we are attempting to constrain the timescale of response through radiocarbon dating of deep soil organic matter in which stable C isotopes record past presence of grassland). The key changes from grassland to forest are loss of organic matter below a thin surface A horizon and greatly enhanced mobility and downward translocation of clay - particularly smectite - in forest soils. This results in upper soil horizons that have relatively low smectite content and low microaggregate stability (as detected through laser diffraction analysis of aggregate disintegration in laboratory experiments), especially below the thin A horizon. The best explanation for this change appears to involve differences in how OM is added to and accumulated in the soil under forest and grassland; soil acidity and base saturation change more gradually eastward along a gradient more likely to reflect climate than vegetation. Evidence of bioturbation (especially gopher burrowing) is much more common at former grassland sites. In addition to mixing OM downward in the soil, burrowing moves detrital carbonates upward, probably enhancing OM accumulation and aggregate stability. Research on geomorphic response to Holocene climatic change in the Midwestern US has often emphasized higher potential

  17. Arthropod diversity in pure oak forests of coppice origin in northern Thrace (Turkey

    Directory of Open Access Journals (Sweden)

    Keten A

    2015-10-01

    Full Text Available Oak (Quercus spp. forests are among the most important forest types in Turkey. In the past, oak forests were managed through coppice clear-cutting, but in recent decades they have mostly been converted to high forest. This study was aimed at explaining how arthropod diversity is affected during conversion from coppice to high oak forest and during the early stages of coppice succession. We tested the hypothesis that arthropod richness, abundance and diversity in coppice oak sites varied according to stand age and a number of other forest characteristics. Arthropod communities were sampled in 50 plots using four different methods: pitfall traps, sweep nets, sticky cards and cloth shaking. A total of 13 084 individuals were collected and classified into 193 Recognizable Taxonomic Units (RTUs, with the most RTUs and the greatest number of specimens captured by sweep netting. We identified 17 taxa within RTU’s with more than 1% of the captured arthropods, which constituted 75% of the total specimens. The number of RTUs varied significantly according to trap type. Arthropod richness and Shannon-Wiener biodiversity index (H′ increased with elevation and precipitation. In young (1-40 yrs-old and middle-aged (41-80 yrs stands, arthropod biodiversity was not significantly affected by stand type, but slightly increased with diameter at breast height and tree height. Forest characteristics, such as the litter layer, understory and crown diameter, weakly influenced arthropod richness and abundance. Cluster analysis revealed that stand types and trap types differed taxonomically. Principal component analysis showed that stand types were clearly separated by the stand parameters measured. Insect families (Formicidae, Thripidae, Lygaeidae, Dolichopodidae, Luaxanidae, Cicadellidae and Ichneumonidae could potentially be used as indicators of coppice oak conditions. As the coppice oak changes to mature forest, further studies are needed to better assess the

  18. Using multi-resolution remote sensing to monitor disturbance and climate change impacts on northern forests

    Science.gov (United States)

    Sulla-Menashe, Damien

    Global forests are experiencing a variety of stresses in response to climate change and human activities. The broad objective of this dissertation is to improve understanding of how temperate and boreal forests are changing by using remote sensing to develop new techniques for detecting change in forest ecosystems and to use these techniques to investigate patterns of change in North American forests. First, I developed and applied a temporal segmentation algorithm to an 11-year time series of MODIS data for a region in the Pacific Northwest of the USA. Through comparison with an existing forest disturbance map, I characterized how the severity and spatial scale of disturbances affect the ability of MODIS to detect these events. Results from these analyses showed that most disturbances occupying more than one-third of a MODIS pixel can be detected but that prior disturbance history and gridding artifacts complicate the signature of forest disturbance events in MODIS data. Second, I focused on boreal forests of Canada, where recent studies have used remote sensing to infer decreases in forest productivity. To investigate these trends, I collected 28 years of Landsat TM and ETM+ data for 11 sites spanning Canada's boreal forests. Using these data, I analyzed how sensor geometry and intra- and inter-sensor calibration influence detection of trends from Landsat time series. Results showed systematic patterns in Landsat time series that reflect sensor geometry and subtle issues related to inter-sensor calibration, including consistently higher red band reflectance values from TM data relative to ETM+ data. In the final chapter, I extended the analyses from my second chapter to explore patterns of change in Landsat time series at an expanded set of 46 sites. Trends in peak-summer values of vegetation indices from Landsat were summarized at the scale of MODIS pixels. Results showed that the magnitude and slope of observed trends reflect patterns in disturbance and land

  19. Multi-decade biomass dynamics in an old-growth hemlock-northern hardwood forest, Michigan, USA

    Directory of Open Access Journals (Sweden)

    Kerry D. Woods

    2014-09-01

    Full Text Available Trends in living aboveground biomass and inputs to the pool of coarse woody debris (CWD in an undisturbed, old-growth hemlock-northern hardwood forest in northern MI were estimated from multi-decade observations of permanent plots. Growth and demographic data from seven plot censuses over 47 years (1962–2009, combined with one-time measurement of CWD pools, help assess biomass/carbon status of this landscape. Are trends consistent with traditional notions of late-successional forests as equilibrial ecosystems? Specifically, do biomass pools and CWD inputs show consistent long-term trends and relationships, and can living and dead biomass pools and trends be related to forest composition and history? Aboveground living biomass densities, estimated using standard allometric relationships, range from 360–450 Mg/ha among sampled stands and types; these values are among the highest recorded for northeastern North American forests. Biomass densities showed significant decade-scale variation, but no consistent trends over the full study period (one stand, originating following an 1830 fire, showed an aggrading trend during the first 25 years of the study. Even though total above-ground biomass pools are neither increasing nor decreasing, they have been increasingly dominated, over the full study period, by very large (>70 cm dbh stems and by the most shade-tolerant species (Acer saccharum and Tsuga canadensis.CWD pools measured in 2007 averaged 151 m3/ha, with highest values in Acer-dominated stands. Snag densities averaged 27/ha, but varied nearly ten-fold with canopy composition (highest in Tsuga-dominated stands, lowest in Acer-dominated; snags constituted 10–50% of CWD biomass. Annualized CWD inputs from tree mortality over the full study period averaged 1.9–3.2 Mg/ha/yr, depending on stand and species composition. CWD input rates tended to increase over the course of the study. Input rates may be expected to increase over longer

  20. Combustion efficiency and emission factors for wildfire-season fires in mixed conifer forests of the northern Rocky Mountains, US

    Directory of Open Access Journals (Sweden)

    S. P. Urbanski

    2013-07-01

    Full Text Available In the US, wildfires and prescribed burning present significant challenges to air regulatory agencies attempting to achieve and maintain compliance with air quality regulations. Fire emission factors (EF are essential input for the emission models used to develop wildland fire emission inventories. Most previous studies quantifying wildland fire EF of temperate ecosystems have focused on emissions from prescribed burning conducted outside of the wildfire season. Little information is available on EF for wildfires in temperate forests of the conterminous US. The goal of this work is to provide information on emissions from wildfire-season forest fires in the northern Rocky Mountains, US. In August 2011, we deployed airborne chemistry instruments and sampled emissions over eight days from three wildfires and a prescribed fire that occurred in mixed conifer forests of the northern Rocky Mountains. We measured the combustion efficiency, quantified as the modified combustion efficiency (MCE, and EF for CO2, CO, and CH4. Our study average values for MCE, EFCO2, EFCO, and EFCH4 were 0.883, 1596 g kg−1, 135 g kg−1, 7.30 g kg−1, respectively. Compared with previous field studies of prescribed fires in temperate forests, the fires sampled in our study had significantly lower MCE and EFCO2 and significantly higher EFCO and EFCH4. The fires sampled in this study burned in areas reported to have moderate to heavy components of standing dead trees and down dead wood due to insect activity and previous fire, but fuel consumption data was not available. However, an analysis of MCE and fuel consumption data from 18 prescribed fires reported in the literature indicates that the availability of coarse fuels and conditions favorable for the combustion of these fuels favors low MCE fires. This analysis suggests that fuel composition was an important factor contributing to the low MCE of the fires measured in this study. This study only measured EF for CO2, CO

  1. Sap-feeding insects on forest trees along latitudinal gradients in northern Europe: a climate-driven patterns.

    Science.gov (United States)

    Kozlov, Mikhail V; Stekolshchikov, Andrey V; Söderman, Guy; Labina, Eugenia S; Zverev, Vitali; Zvereva, Elena L

    2015-01-01

    Knowledge of the latitudinal patterns in biotic interactions, and especially in herbivory, is crucial for understanding the mechanisms that govern ecosystem functioning and for predicting their responses to climate change. We used sap-feeding insects as a model group to test the hypotheses that the strength of plant-herbivore interactions in boreal forests decreases with latitude and that this latitudinal pattern is driven primarily by midsummer temperatures. We used a replicated sampling design and quantitatively collected and identified all sap-feeding insects from four species of forest trees along five latitudinal gradients (750-1300 km in length, ten sites in each gradient) in northern Europe (59 to 70°N and 10 to 60°E) during 2008-2011. Similar decreases in diversity of sap-feeding insects with latitude were observed in all gradients during all study years. The sap-feeder load (i.e. insect biomass per unit of foliar biomass) decreased with latitude in typical summers, but increased in an exceptionally hot summer and was independent of latitude during a warm summer. Analysis of combined data from all sites and years revealed dome-shaped relationships between the loads of sap-feeders and midsummer temperatures, peaking at 17 °C in Picea abies, at 19.5 °C in Pinus sylvestris and Betula pubescens and at 22 °C in B. pendula. From these relationships, we predict that the losses of forest trees to sap-feeders will increase by 0-45% of the current level in southern boreal forests and by 65-210% in subarctic forests with a 1 °C increase in summer temperatures. The observed relationships between temperatures and the loads of sap-feeders differ between the coniferous and deciduous tree species. We conclude that climate warming will not only increase plant losses to sap-feeding insects, especially in subarctic forests, but can also alter plant-plant interactions, thereby affecting both the productivity and the structure of future forest ecosystems. © 2014

  2. Nonlinear response of canopy developmental rate to temperature in temperate and boreal forest in the Northern Hemisphere

    Science.gov (United States)

    Park, H.; Ho, C. H.; Jeong, S. J.

    2015-12-01

    Understanding the changes in vegetation annual cycle is crucial for improving our knowledge about various interactions between the terrestrial ecosystem and climate. However, our understanding about the vegetation seasonality is mostly confined to some phenological timings such as spring emergence and fall senescence. This study assessed large-scale variations in the vegetation green-up rate (VGrate), which indicates the rate of canopy development from winter dormancy to summer maturity, and its relationship over Northern Hemisphere temperate and boreal forests for 1982-2011. VGrate and local temperature changes show a positive correlation over the region of interest, and it indicates that a temperature increase during green-up period leads to faster canopy development. The responses of VGrate tend to be more sensitive to positive temperature anomalies than negative anomalies despite same magnitude of the temperature changes. These nonlinear responsiveness of VGrate to local temperature change is clearly observed in deciduous broadleaf forests over Eurasia compared to woodlands over North America. These results suggest that anomalous warming in green-up period would make canopy developments faster over wide temperate and boreal forest areas.

  3. Problems of habitat management for deer and elk in the northern forests

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This article discusses wildlife habitat problems and research needs in the northern Rocky Mountains and is focused primarily on habitats of deer and elk. The article...

  4. Line - organised convection putting fire to forest area of Halkidiki, Northern Greece

    Science.gov (United States)

    Vlachou, M.; Brikas, D.; Pytharoulis, I.

    2010-09-01

    The organisation of convection in a line often coincides with the end of heat waves in the Southern Balkans. This was indeed the case on the 21st of August 2006, when the tail of an eastward moving cold front put an end to the preceding heat wave and, at the same time, triggered thunderstorms and windstorms in Southern Bulgaria and Northern Greece. The associated electric activity initiated a fire in Kassandra, Halkidiki, Greece. Due to the prolonged drought and the strong winds, the fire spread quickly. It lasted for three days, costing two human lives, burning an extended forest area, as well as destroying hotels and resort facilities. Availabla data are: i) European Centre for Medium - range Weather Forecasts (ECMWF) analyses, ii) RADAR reflectivity data from the Weather Modification Dept. of the Hellenic Agricultural Insurance Organisation and iii) surface and upper air data from the airport ‘Makedonia’ of Thessaloniki, Greece. The heat wave, that affected Greece during the 5 - day period prior to the line convection, was associated with the establishment of a hot, but very stable at low levels, boundary layer, probably modified part of the Saharan air layer, advected to the area of interest. Destabilisation occurred due to surface heating, as well as upper level cold air advection. From the synoptic point of view, upward motion prevails under the inflection point of the subtropical and polar jet streams, indicating once more how important are, for upper level divergence, the curvature changes along the flow. In the meso-α scale, the line convection formed along and just ahead of a shallow, frontogenetically active cold frontal zone. Hence, the line under study may be called a squall line. It is suggested that such zones play a key role in triggering severe weather in the same area, as well as cyclogenesis in the Mediterranean area. Previous studies have shown numerous severe weather events to occur along such zones. In the meso-β scale, the line under

  5. Barringer Meteor Crater, Arizona

    Science.gov (United States)

    2001-01-01

    Barringer Crater, also known as 'Meteor Crater,' is a 1,300-meter (0.8 mile) diameter, 174-meter (570-feet) deep hole in the flat-lying desert sandstones 30 kilometers (18.6 miles) west of Winslow, Arizona. Since the 1890s geologic studies here played a leading role in developing an understanding of impact processes on the Earth, the moon and elsewhere in the solar system.This view was acquired by the Landsat 4 satellite on December 14, 1982. It shows the crater much as a lunar crater might appear through a telescope. Morning sun illumination is from the southeast (lower right). The prominent gully meandering across the scene is known as Canyon Diablo. It drains northward toward the Little Colorado River and eventually to the Grand Canyon. The Interstate 40 highway crosses and nearly parallels the northern edge of the scene.The ejecta blanket around the crater appears somewhat lighter than the surrounding terrain, perhaps in part due to its altered mineralogic content. However, foot traffic at this interesting site may have scarred and lightened the terrain too. Also, the roughened surface here catches the sunlight on the southerly slopes and protects a highly reflective patchy snow cover in shaded northerly slopes, further lightening the terrain as viewed from space on this date.

  6. Plant biodiversity of beech forests in central-northern Italy: a methodological approach for conservation purposes

    Directory of Open Access Journals (Sweden)

    Marcantonio M

    2012-07-01

    Full Text Available Forests are reckoned essentials as biodiversity reservoirs and carbon sinks. Current threats to forest ecosystems (e.g., climate changes, habitat loss and fragmentation, management changes call for monitoring their biodiversity and preserving their ecological functions. In this study, we characterized plants diversity of five beech forests located in central and north Apennines mountain chain, using results by a probabilistic sampling. In order to achieve our goals, we have considered species richness and abundance, taxonomic distinctness and species composition, using both old and new analytical approaches. Results have shown how: (1 the forest type dominated by Fagus sylvatica is characterized by high complexity, with marked compositional, structural and biodiversity differences; (2 beech forests of Pigelleto di Piancastagnaio and Valle della Corte show the highest plants diversity values. The ecological characteristics of these areas, which sustain high diversity values, are unique and of great conservation interest; (3 the use of species richness as the only diversity measure have not allowed an efficient differentiation between studied areas. Indeed, the use of different indexes and analytical methods is required to detect multiple characteristics of biological diversity, as well as to carry out efficient biodiversity surveys aimed to develop optimal conservation strategies. In the future, we plan to apply the sampling methodology and the analytical approach used in this paper to characterize plants diversity of similar forest types.

  7. Evidence of formation of submicrometer water-soluble organic aerosols at a deciduous forest site in northern Japan in summer

    Science.gov (United States)

    Miyazaki, Yuzo; Jung, Jinsang; Fu, Pingqing; Mizoguchi, Yasuko; Yamanoi, Katsumi; Kawamura, Kimitaka

    2012-10-01

    Semicontinuous measurements of submicrometer water-soluble organic aerosols and particle size distributions were conducted at a deciduous forest site in northern Japan in August 2010. Increases in particle number concentration were frequently observed in daytime, accompanied by an increase in the concentrations of water-soluble organic carbon (WSOC). We found that daily averaged WSOC concentrations positively correlated with gross primary production of CO2 by the forest ecosystem (r2 = 0.63) and ambient temperature during daytime. These relations suggest that the formation of WSOC is closely linked to photosynthetic activity by the forest ecosystem, which depends on both temperature and solar radiation. Off-line chemical analysis of samples of particles with aerodynamic diameter smaller than 1 μm collected during a 2 day event of elevated WSOC levels suggests that photochemical aging of both α- andβ-pinene and isoprene oxidation products contributes to the particle growth and the WSOC mass. Organic tracers of primary biological aerosol particles (PBAPs) showed distinct diurnal variations with a maximum around noontime, also indicating that higher temperature and light intensity induce emissions of PBAPs. However, their contribution to the submicrometer WSOC mass was likely insignificant. During the day, the concentrations of 3-methyl-1,2,3-butanetricarboxylic acid (3-MBTCA) showed a strong dependence on temperature, and the ratios of WSOC to particle volume concentration increased with an increase in the concentration ratios of 3-MBTCA to pinonic acid (PA). This result supports a previous proposal that the 3-MBTCA/PA ratios in submicrometer particles can be a useful tracer for chemical aging of biogenic secondary organic aerosol from forest vegetation.

  8. Effects of grazing on natural regeneration of tree and herb species of Kheyroud forest in northern Iran

    Institute of Scientific and Technical Information of China (English)

    Mohsen Javanmiri Pour; Mohmmad Reza Marvie Mohadjer; Vahid Etemad; Mahmoud Zobeiri

    2012-01-01

    We investigated the effects of grazing on natural regeneration,quantity,and diversity of woody species and dominant herb species in Kheyroud forest in northern Iran.We sampled vegetation in 5m2 plots in custom units,which are demarcated resource areas traditionally used by local livestock producers.The authors quantified number of species,height of seedlings,and diameter of seedlings.Height classes were 0-30 cm,30-130 cm,and >130 cm,and diameter classes were 0-2.5 cm,2.5-5 cm and 5-7.5 cm.The density of seedlings declined with distance from corral until reaching the custom unit boundary.Most seedlings had diameters of 0-2.5 cm and heights of 0-30 cm.Predominant species,Carpinus betulus and Acer capadocicum,were in plots near the centers of custom units,Fagus orientalis,Acer velutinum,Quercus castanifolia species were dominant in plots near the custom unit boundary.Plant species such as Oplismenus undulatifolius,Euphorbia amygdaloides,Rubus fruticos and Pteridium aquilinum were dominant in plots nearer to forest corral.Healthy seedlings were more numerous in plots nearest the corral,while defective and deformed seedlings were more abundant away from the corral.We conclude that grazing had negative effects on the quantity and quality of vegetative regeneration.Continuation of overgrazing will not only endanger the sustainability of forest ecosystems,but also will increase the challenge of sustainable forest management.

  9. Trends in dynamics of forest upper boundary in high mountains of northern Baikal area

    Directory of Open Access Journals (Sweden)

    V. I. Voronin

    2016-08-01

    Full Text Available Studies of spatial-temporal variability of the upper boundary of the forest on the north-western coast of Lake Baikal (Baikal and Upper Angara Ridges are performed on the base of the analysis of forests renewal processes and of the dynamics of larch radial increment in the ecotone of the forest upper boundary and out of it. The presence of a large amount of well-developed uplands and circuses with considerable heights drops in the structure of mountain system favours formation of interrupted boundary between forest and subgoltsy belt. The timber stand of the upper forest boundary in the studied area is represented by Daurian larch. Three tree-ring chronologies of larch are obtained. The longest chronology is obtained for mountain taiga belt of Baikal Ridge and is as long as 460 years. Since 1980ies, a sustainable trend of increase of radial trees growth is observed. It is observed the most distinctly in trees of the upper forest boundary on the Baikal Ridge. There is advancing of trees species into subgoltsy belt and into mountain tundra, which depends, respectively, on slopes heights, exposition and tilting, on sites of growth of concrete cenoses. Modern peculiarity of the vegetation of the studied area is presence of abundant viable larch undergrowth (from 2–3 to 25 y.o. and fir in the ecotone of upper forest boundary and in subgoltsy belt, as well as appearing of single specimens of spruce. Main undergrowth mass (2/3 is presented by trees aged in average 15–25 y.o., i.e., they appeared in late 1980ies. Due to increase of snow cover thickness in winter, the trees young growth obtained great protection from freezing resulting in the increase of ability of young growth to live up to elder age.

  10. Tree Line Structure and Dynamics at the Northern Limit of the Larch Forest: Anabar Plateau, Siberia, Russia

    Science.gov (United States)

    Kharuk, Viacheslav I.; Ranson, Kenneth J.; Im, Sergey T.; Oskorbin, Pavel A.; Dvinskaya, Maria L.; Ovchinnikov, Dmitriy V.

    2013-01-01

    The goal of the study was to provide an analysis of climate impact before, during, and after the Little Ice Age (LIA) on the larch (Larix gmelinii) tree line at the northern extreme of Siberian forests. Recent decadal climate change impacts on the tree line, regeneration abundance, and age structure were analyzed. The location of the study area was within the forest-tundra ecotone (elevation range 170-450 m) in the Anabar Plateau, northern Siberia. Field studies were conducted along elevational transects. Tree natality/mortality and radial increment were determined based on dendrochronology analyses. Tree morphology, number of living and subfossil trees, regeneration abundance, and age structure were studied. Locations of pre-LIA, LIA, and post-LIA tree lines and refugia boundaries were established. Long-term climate variables and drought index were included in the analysis. It was found that tree mortality from the 16th century through the beginning of the 19th century caused a downward tree line recession. Sparse larch stands experienced deforestation, transforming into tundra with isolated relict trees. The maximum tree mortality and radial growth decrease were observed to have occurred at the beginning of 18th century. Now larch, at its northern boundary in Siberia, is migrating into tundra areas. Upward tree migration was induced by warming in the middle of the 19th century. Refugia played an important role in repopulation of the forest-tundra ecotone by providing a seed source and shelter for recruitment of larch regeneration. Currently this ecotone is being repopulated mainly by tree cohorts that were established after the 1930s. The last two decades of warming did not result in an acceleration of regeneration recruitment because of increased drought conditions. The regeneration line reached (but did not exceed) the pre-LIA tree line location, although contemporary tree heights and stand densities are comparatively lower than in the pre-LIA period. The mean

  11. Varying rotation lengths in northern production forests: Implications for habitats provided by retention and production trees.

    Science.gov (United States)

    Felton, Adam; Sonesson, Johan; Nilsson, Urban; Lämås, Tomas; Lundmark, Tomas; Nordin, Annika; Ranius, Thomas; Roberge, Jean-Michel

    2017-02-24

    Because of the limited spatial extent and comprehensiveness of protected areas, an increasing emphasis is being placed on conserving habitats which promote biodiversity within production forest. For this reason, alternative silvicultural programs need to be evaluated with respect to their implications for forest biodiversity, especially if these programs are likely to be adopted. Here we simulated the effect of varied rotation length and associated thinning regimes on habitat availability in Scots pine and Norway spruce production forests, with high and low productivity. Shorter rotation lengths reduced the contribution made by production trees (trees grown for industrial use) to the availability of key habitat features, while concurrently increasing the contribution from retention trees. The contribution of production trees to habitat features was larger for high productivity sites, than for low productivity sites. We conclude that shortened rotation lengths result in losses of the availability of habitat features that are key for biodiversity conservation and that increased retention practices may only partially compensate for this. Ensuring that conservation efforts better reflect the inherent variation in stand rotation lengths would help improve the maintenance of key forest habitats in production forests.

  12. Unconventional gas development and its effect on forested ecosystems in the Northern Appalachians, USA

    Science.gov (United States)

    Drohan, Patrick; Brittingham, Margaret; Mortensen, David; Barlow, Kathryn; Langlois, Lillie

    2017-04-01

    Worldwide unconventional shale-gas development has the potential to cause substantial landscape disturbance. The northeastern U.S.A. Appalachian Mountains across the states of Pennsylvania, West Virginia, Ohio, and Kentucky, are experiencing rapid landscape change as unconventional gas development occurs. We highlight several years of our research from this region in order to demonstrate the unique effect unconventional development has had on forested ecosystems. Infrastructure development has had a wide-reaching and varied effect on forested ecosystems and their services, which has resulted in temporary disturbances and long-lasting ones altering habitats and their viability. Corridor disturbances, such as pipelines, are the most spatially extensive disturbance and have substantially fragmented forest cover. Core forest disturbance, especially, in upper watershed positions, has resulted in disproportionate disturbances to forested ecosystems and their wildlife, and suggests a need for adaptive land management strategies to minimize and mitigate the effects of gas development. Soil and water resources are most affected by surface disturbances; however, soil protection and restoration strategies are evolving as the gas play changes economically. Dynamic soil properties related to soil organic matter and water availability respond uniquely to unconventional gas development and new, flexible restoration strategies are required to support long-term ecosystem stability. While the focus of management and research to date has been on acute disturbances to forested ecosystems, unconventional gas development is clearly a greater chronic, long-term disturbance factor in the Appalachian Mountains. Effectively managing ecosystems where unconventional gas development is occurring is a complicated interplay between public, private and corporate interests.

  13. A Framework for Integrating Transboundary Values, Landscape Connectivity, and ′Protected Areas′ Values Within a Forest Management Area in Northern Alberta

    Directory of Open Access Journals (Sweden)

    Jim Witiw

    2015-01-01

    Full Text Available Daishowa-Marubeni International (DMI is an integrated forest products company with operations in northern Alberta, Canada. As part of its sustainable forestry practices, it has embarked on a comprehensive plan to maintain biodiversity and landscape connectivity values within its area of operation. In addition to identification of High Conservation Value Forests (HCVF as part of an internal forest planning system and to assist forest certification interests, DMI has developed a plan for a Continuous Reserve Network (CRN. This paper describes the rationale behind DMI′s decision to identify a framework for both HCVF and the CRN. The company believes this CRN is a novel approach to ensuring visibility of connected landscape processes. DMI has introduced the concept to government, local sawmill stakeholders, and its public advisory committee, with a goal towards implementing the CRN within the area of its forest tenure as part of its forest management plan. The CRN represents nearly 44% of DMI′s tenure area, and thus makes a significant contribution to landscape connectivity and forest biodiversity. The case study represents an example where values and goals of legislated protected areas are also captured by management prescriptions within non-harvestable areas and timber-producing forests associated with an ecosystem-based approach to sustainable forest management.

  14. Plant diversity and regeneration in a disturbed isolated dry Afromontane forest in northern Ethiopia

    DEFF Research Database (Denmark)

    Aynekulu, Ermias; Aerts, Raf; Denich, Manfred

    2016-01-01

    vegetation on steep slopes with shallow soils, a Pterolobium stellatum-Celtis africana community, found on more mesic sites, and a Cadia purpurea-Opuntia ficus-indica community, typically representing severely disturbed habitats. Altitude, slope, soil depth and distance to the nearest stream, which we......, such as Afrocarpus falcatus, Allophylus abyssinicus and Bersama abyssinica, are still present as mature trees, and as other forest fragments in the region are two orders of magnitude smaller, and therefore more heavily impacted by small population sizes and unfavourable edge effects. Forest management should focus...

  15. Absence of vaccinia virus detection in a remote region of the Northern Amazon forests, 2005-2015.

    Science.gov (United States)

    Costa, Galileu Barbosa; Lavergne, Anne; Darcissac, Edith; Lacoste, Vincent; Drumond, Betânia Paiva; Abrahão, Jônatas Santos; Kroon, Erna Geessien; de Thoisy, Benoît; de Souza Trindade, Giliane

    2017-08-01

    Vaccinia virus (VACV) circulates in Brazil and other South America countries and is responsible for a zoonotic disease that usually affects dairy cattle and humans, causing economic losses and impacting animal and human health. Furthermore, it has been detected in wild areas in the Brazilian Amazon. To better understand the natural history of VACV, we investigated its circulation in wildlife from French Guiana, a remote region in the Northern Amazon forest. ELISA and plaque reduction neutralization tests were performed to detect anti-orthopoxvirus antibodies. Real-time and standard PCR targeting C11R, A56R and A26L were applied to detect VACV DNA in serum, saliva and tissue samples. No evidence of VACV infection was found in any of the samples tested. These findings provide additional information on the VACV epidemiological puzzle. The virus could nevertheless be circulating at low levels that were not detected in areas where no humans or cattle are present.

  16. Soil microbial responses to forest floor litter manipulation and nitrogen addition in a mixed-wood forest of northern China.

    Science.gov (United States)

    Sun, Xiao-Lu; Zhao, Jing; You, Ye-Ming; Jianxin Sun, Osbert

    2016-01-14

    Changes in litterfall dynamics and soil properties due to anthropogenic or natural perturbations have important implications to soil carbon (C) and nutrient cycling via microbial pathway. Here we determine soil microbial responses to contrasting types of litter inputs (leaf vs. fine woody litter) and nitrogen (N) deposition by conducting a multi-year litter manipulation and N addition experiment in a mixed-wood forest. We found significantly higher soil organic C, total N, microbial biomass C (MBC) and N (MBN), microbial activity (MR), and activities of four soil extracellular enzymes, including β-glucosidase (BG), N-acetyl-β-glucosaminidase (NAG), phenol oxidase (PO), and peroxidase (PER), as well as greater total bacteria biomass and relative abundance of gram-negative bacteria (G-) community, in top soils of plots with presence of leaf litter than of those without litter or with presence of only fine woody litter. No apparent additive or interactive effects of N addition were observed in this study. The occurrence of more labile leaf litter stimulated G-, which may facilitate microbial community growth and soil C stabilization as inferred by findings in literature. A continued treatment with contrasting types of litter inputs is likely to result in divergence in soil microbial community structure and function.

  17. Landscape epidemiology and control of pathogens with cryptic and long-distance dispersal: sudden oak death in northern Californian forests.

    Directory of Open Access Journals (Sweden)

    João A N Filipe

    2012-01-01

    Full Text Available Exotic pathogens and pests threaten ecosystem service, biodiversity, and crop security globally. If an invasive agent can disperse asymptomatically over long distances, multiple spatial and temporal scales interplay, making identification of effective strategies to regulate, monitor, and control disease extremely difficult. The management of outbreaks is also challenged by limited data on the actual area infested and the dynamics of spatial spread, due to financial, technological, or social constraints. We examine principles of landscape epidemiology important in designing policy to prevent or slow invasion by such organisms, and use Phytophthora ramorum, the cause of sudden oak death, to illustrate how shortfalls in their understanding can render management applications inappropriate. This pathogen has invaded forests in coastal California, USA, and an isolated but fast-growing epidemic focus in northern California (Humboldt County has the potential for extensive spread. The risk of spread is enhanced by the pathogen's generalist nature and survival. Additionally, the extent of cryptic infection is unknown due to limited surveying resources and access to private land. Here, we use an epidemiological model for transmission in heterogeneous landscapes and Bayesian Markov-chain-Monte-Carlo inference to estimate dispersal and life-cycle parameters of P. ramorum and forecast the distribution of infection and speed of the epidemic front in Humboldt County. We assess the viability of management options for containing the pathogen's northern spread and local impacts. Implementing a stand-alone host-free "barrier" had limited efficacy due to long-distance dispersal, but combining curative with preventive treatments ahead of the front reduced local damage and contained spread. While the large size of this focus makes effective control expensive, early synchronous treatment in newly-identified disease foci should be more cost-effective. We show how the

  18. Fine Root Dynamics and Forest Production Across a Calcium Gradient in Northern Hardwood and Conifer Ecosystems

    Science.gov (United States)

    Byung Bae Park; Ruth D. Yanai; Timothy J. Fahey; Scott W. Bailey; Thomas G. Siccama; James B. Shanley; Natalie L. Cleavitt

    2008-01-01

    Losses of soil base cations due to acid rain have been implicated in declines of red spruce and sugar maple in the northeastern USA. We studied fine root and aboveground biomass and production in five northern hardwood and three conifer stands differing in soil Ca status at Sleepers River, VT; Hubbard Brook, NH; and Cone Pond, NH. Neither aboveground biomass and...

  19. Who knows? Local non-timber forest product knowledge and stewardship practices in northern Michigan

    Science.gov (United States)

    Marla R. Emery

    2001-01-01

    Non-timber forest product (NTFP) literature frequently laments the absence of an information base for policy and management decisions. While formal scientific data on the biological and social ecologies of most NTFPs are limited to nonexistent, long-time gatherers often have extensive experiential knowledge bases. Researchers and managers may overlook this expertise...

  20. Isotopic signals of summer denitrification in a northern hardwood forested catchment

    Science.gov (United States)

    Sarah K. Wexler; Christine L. Goodale; Kevin J. McGuire; Scott W. Bailey; Peter M. Groffman

    2014-01-01

    Despite decades of measurements, the nitrogen balance of temperate forest catchments remains poorly understood. Atmospheric nitrogen deposition often greatly exceeds streamwater nitrogen losses; the fate of the remaining nitrogen is highly uncertain. Gaseous losses of nitrogen to denitrification are especially poorly documented and are often ignored. Here, we provide...

  1. Cradle-to-gate life cycle impacts of redwood forest resource harvesting in northern California

    Science.gov (United States)

    Han-Sup Han; Elaine Oneil; Richard D. Bergman; Ivan L. Eastin; Leonard R. Johnson

    2015-01-01

    The first life cycle impact assessment for redwood (Sequoia sempervirens) forest management activities (i.e. a cradle-to-sawmill gate input) including the growing, harvesting, and hauling of redwood sawlogs to a sawmill was completed. In the stump-to-truck timber harvesting analysis, primary transport activities such as skidding and yarding consumed...

  2. Stable water isotopes suggest sub-canopy water recycling in a northern forested catchment

    Science.gov (United States)

    Mark B. Green; Bethany K. Laursen; John L. Campbell; Kevin J. McGuire; Eric P. Kelsey

    2015-01-01

    Stable water isotopes provide a means of tracing many hydrologic processes, including poorly understood dynamics like soil water interactions with the atmosphere. We present a four-year dataset of biweekly water isotope samples from eight fluxes and stores in a headwater catchment at the Hubbard Brook Experimental Forest, New Hampshire, USA. We use Dansgaard's...

  3. Soil Inorganic Nitrogen Cycling during Successional Change in a Northern Temperate Forest

    Science.gov (United States)

    Nave, L. E.; Sparks, J. P.; Le Moine, J.; Hardiman, B. S.; Nadelhoffer, K. J.; Strahm, B. D.; Curtis, P.

    2012-12-01

    Transformations and fluxes of inorganic nitrogen (N) compounds in forest soils are the basis for major biogeochemical functions. Inorganic N fluxes contribute significantly to plant and microbial N nutrition, mediate the exchange of reactive, gas-phase N between the biosphere and atmosphere, and are coupled via hydrologic linkages to N cycling in surface and groundwater. However, soil inorganic N cycling may change during forest succession due to shifts in tree species composition, ecosystem N capital and distribution, or other drivers. Within the framework of a paired-ecosystem, experimentally accelerated successional advancement, we synthesized comprehensive measurements of soil and soil surface inorganic N fluxes to: a) quantify changes in, and interactions between, the component processes of the N cycle that mediate forest biogeochemical functions, and b) understand how these processes and associated biogeochemical functions change during forest succession. We hypothesized that a sudden decline in plant N uptake during the mortality event that accelerated ongoing succession would significantly increase NH4+ availability, prompting fundamental changes to the N cycle including the initiation of significant nitrification and increased exports of NO3- derived compounds in gas phase and soil solution. We found that in surface soils (top 20 cm), levels of seasonally integrated, ion-exchange NH4+ and NO3- availability increased with decreasing fine root biomass (regression, Pstructural drivers of N cycling that are undergoing incipient successional changes, and b) recent and continued successional advancement has shifted the N cycling economy of this ecosystem towards greater importance of NO3-.

  4. Persistent spread in seasonal albedo change radiative forcings linked to forest cover changes at northern latitudes

    Science.gov (United States)

    Bright, R. M.; Myhre, G.; Astrup, R. A.; Antón-Fernández, C.; Strømman, A. H.

    2014-12-01

    Large-scale land use and land cover change (LULCC) can significantly affect regional climates from changes in surface biogeophysics, and a substantial part of historical LULCC from forest to crop or pasture occurred in the mid- and high-latitudes of North America and Eurasia where the snow-masking effect of forests often leads to a negative radiative forcing from albedo changes linked to deforestation. Results from several recent historical LULCC modeling studies, however, reveal an order of magnitude spread in climate forcing from the snow-masking effect by forests. This is likely because, in months with snow cover, the interactions between vegetation and snow significantly complicate the relationship between the change in forest cover fraction and albedo, thus accurate characterizations of land surface-albedo dynamics are essential given the importance of albedo feedbacks when ground or canopy surfaces are covered in snow Here, we evaluate snow masking parameterization schemes of seven prominent climate models in greater detail in order to pinpoint major sources of the persistent variability in albedo predictions across models. Using a comprehensive dataset of forest structure, meteorology, and daily MODIS albedo observations spanning three winter-spring seasons in three regions of boreal Norway, we estimate radiative forcings connected to canopy snow masking and compare it to the observed forcings. We develop a physically-based regression model and compare its performance to existing modeling schemes, concluding with a discussion on the utility of purely empirical parameterizations relative to those rooted in radiative transfer theory and/or process-based modeling.

  5. Forest management as possible driver in mitigating climate change impacts at northern latitudes

    Science.gov (United States)

    Collalti, Alessio; Trotta, Carlo; Santini, Monia; Matteucci, Giorgio

    2017-04-01

    Climate change is likely to impact the dynamics of carbon and water cycles in forests over the next century. To date, it is still debated how forests will react. Some key variables may help in understanding the extent at which terrestrial ecosystems will be affected. Carbon Use Efficiency (CUE) and Water Use Efficiency (WUE) represent some of these key aspects. CUE represents the capacity of the forests to transfer carbon from the atmosphere to the terrestrial biomass, WUE the carbon gained for the water lost via canopy transpiration. Hence, both are key variables since they intimately represent the effects of several coupled ecophysiological processes affected by climate change. Here, we analyzed how within the 3D-CMCC-CNR FEM, forced by five general circulation model data and the four representative concentration pathways, the modeled CUE and WUE are affected by, from seasonal to over medium- and long-time period, warming, rising atmospheric [CO2] and management, assessing at which extent each component influences model results in an existing boreal forest in Finland. The 3D-CMCC-CNR FEM model results reveal that CUE tends to decrease with warmer scenarios, and management may greatly dampen the effects but only in the short- to medium-time period. WUE can increase consistently owing to the increasing of the CO2 fertilization if coupled with management. These results confirm also, at stand spatial scale resolution, what found globally in other recent studies and suggesting to consider for long-term period alternative forest management practices to enhance these effects in mitigating climate change.

  6. Relationship between environmental parameters and Pinus sylvestris L. site index in forest plantations in northern Spain acidic plateau

    Directory of Open Access Journals (Sweden)

    Bueis T

    2016-06-01

    Full Text Available The assessment of forest productivity at early stages of stand development may help to define the most appropriate silviculture treatment to be applied for each stand. Site index (dominant height at a reference age is a useful tool for forest productivity estimation. The aim of this study was to develop a model to predict site index for Scots pine (Pinus sylvestris L. plantations in northern Spain acidic plateau by using soil (physical, chemical and biochemical, climatic and physiographic parameters. To meet this objective, data from 35 stands classified into three different site quality classes and 63 soil, climatic and physiographic parameters were examined in order to develop a discriminant model. After selecting 12 discriminant models which were biologically consistent and presented the higher cross-validated rate of correct classification, a model including four parameters (latitude, inorganic Al, porosity and microbial biomass carbon as predictors was chosen. The discriminant model classified 71% of cases correctly and no inferior-quality stands were misassigned to the highest quality class. Soil and physiographic parameters included in the above model are easily obtainable in the field or by simple laboratory analysis, thus our results can be easily integrated in operational forestry to determine site quality.

  7. A heat wave during leaf expansion severely reduces productivity and modifies seasonal growth patterns in a northern hardwood forest.

    Science.gov (United States)

    Stangler, Dominik Florian; Hamann, Andreas; Kahle, Hans-Peter; Spiecker, Heinrich

    2016-10-13

    A useful approach to monitor tree response to climate change and environmental extremes is the recording of long-term time series of stem radial variations obtained with precision dendrometers. Here, we study the impact of environmental stress on seasonal growth dynamics and productivity of yellow birch (Betula alleghaniensis Britton) and sugar maple (Acer saccharum Marsh.) in the Great Lakes, St Lawrence forest region of Ontario. Specifically, we research the effects of a spring heat wave in 2010, and a summer drought in 2012 that occurred during the 2005-14 study period. We evaluated both growth phenology (onset, cessation, duration of radial growth, time of maximum daily growth rate) and productivity (monthly and seasonal average growth rates, maximum daily growth rate, tree-ring width) and tested for differences and interactions among species and years. Productivity of sugar maple was drastically compromised by a 3-day spring heat wave in 2010 as indicated by low growth rates, very early growth cessation and a lagged growth onset in the following year. Sugar maple also responded more sensitively than yellow birch to a prolonged drought period in July 2012, but final tree-ring width was not significantly reduced due to positive responses to above-average temperatures in the preceding spring. We conclude that sugar maple, a species that currently dominates northern hardwood forests, is vulnerable to heat wave disturbances during leaf expansion, which might occur more frequently under anticipated climate change.

  8. Structure and floristic composition of tree stand in tropical forest in the Eastern Ghats of northern Andhra Pradesh, India

    Institute of Scientific and Technical Information of China (English)

    C. Sudhakar Reddy; Shilpa Babar; Giriraj Amamath; Chiranjibi Pattanaik

    2011-01-01

    The changes in species composition,abundance and forest stand structure were analyzed across altitudinal regimes in tropical forests of Eastern Ghats of northern Andhra Pradesh,India.Three 1-ha plots were established with one each in low,medium and high altitudes.A total of 153 species,2129 stems (709 stems ·ha-l) of>10 cm girth were enumerated.Species richness and diversity pattern varied along altitudinal gradient and increased with the altitude.Species richness varied from 52 to 110 species·ha-1 and stand density from 639 to 836 stems·ha-1 with average basal area of 34.39 m2·ha-1.Shannon-Wiener index (H) ranged from 4.55 to 5.17.Low altitude (i.e.,Site 1) is dominated by Xylia xylocarpa (59.22) and Lagerstroemia parviflora (23.90),medium altitude (i.e.,Site 2) by Xylia xylocarpa (45.50) Bursera serrata (17.29),and high altitude (i.e.,Site 3) has Schleichera oleosa (28.25) Pterocarpus marsupium (26.55) as predominant species.Taxonomically,Rubiaceae (12 species),Fabaceae (12),Euphorbiaceae (11),Rutaceae (7) and Lauraceae (7) were dominant families.Density-wise,Fabaceae,Combretaceae,Euphorbiaceae,Anacardiaceae and Myrtaceae were abundant.Thus,conservation assessment based on altitudinal regimes and the information on species structure and function can provide baseline information for monitoring and sustaining the biodiversity.

  9. Development of the mixed conifer forest in northern New Mexico and its relationship to Holocene environmental change

    Science.gov (United States)

    Anderson, R. Scott; Jass, R.B.; Toney, J.L.; Allen, C.D.; Cisneros-Dozal, L. M.; Hess, M.; Heikoop, Jeff; Fessenden, J.

    2008-01-01

    Chihuahuen??os Bog (2925??m) in the Jemez Mountains of northern New Mexico contains one of the few records of late-glacial and postglacial development of the mixed conifer forest in southwestern North America. The Chihuahuen??os Bog record extends to over 15,000??cal yr BP. An Artemisia steppe, then an open Picea woodland grew around a small pond until ca. 11,700??cal yr BP when Pinus ponderosa became established. C/N ratios, ??13C and ??15N values indicate both terrestrial and aquatic organic matter was incorporated into the sediment. Higher percentages of aquatic algae and elevated C/N ratios indicate higher lake levels at the opening of the Holocene, but a wetland developed subsequently as climate warmed. From ca. 8500 to 6400??cal yr BP the pond desiccated in what must have been the driest period of the Holocene there. C/N ratios declined to their lowest Holocene levels, indicating intense decomposition in the sediment. Wetter conditions returned after 6400??cal yr BP, with conversion of the site to a sedge bog as groundwater levels rose. Higher charcoal influx rates after 6400??cal yr BP probably result from greater biomass production rates. Only minor shifts in the overstory species occurred during the Holocene, suggesting that mixed conifer forest dominated throughout the record. ?? 2008 University of Washington.

  10. Structural aspects and floristic similarity among tropical dry forest fragments with different management histories in northern Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Daniel Meira Arruda

    2011-02-01

    Full Text Available In order to produce useful knowledge to the initiatives of protection and management of forest fragments, more specifically for tropical dry forests which suffer with frequent anthropic activities, and due to the lack of specific studies, this article aimed describe the structure and the floristic similarity among three areas of dry forest with different management histories. The study was developed in Capitão Enéas municipality, Northern Minas Gerais, Brazil, where three fragments were evaluated, being one in regeneration for 30 years, another submitted to occasional fire and the third with selective cut in small scale. The sampling was developed through the point quarter method considering all the alive phanerophyte individuals with circumference at breast height (CBH > 15 cm. In the three fragments, 512 individuals, distributed in 60 species, 47 genera, and 23 families were sampled. The most representative families were Fabaceae (26, Anacardiaceae (4, Bignoniaceae (3 and Combretaceae (3. However, fourteen families were represented by only one species. Only eight species were common to all fragments - Myracrodruon urundeuva standed out with 26.9% of all sampled individuals - while a great number of species were exclusive of each fragment. The floristic and structural differences between the fragments are possibly related to the history and intensity of management in each area besides the topography variations and the presence or absence of limestone outcrops. These results show the importance of each fragment, indicating that the loss of anyone would cause negative impacts on the regional flora and consequently to the associated biodiversity.

  11. Simulated atmospheric N deposition alters fungal community composition and suppresses ligninolytic gene expression in a northern hardwood forest.

    Directory of Open Access Journals (Sweden)

    Ivan P Edwards

    Full Text Available High levels of atmospheric nitrogen (N deposition may result in greater terrestrial carbon (C storage. In a northern hardwood ecosystem, exposure to over a decade of simulated N deposition increased C storage in soil by slowing litter decay rates, rather than increasing detrital inputs. To understand the mechanisms underlying this response, we focused on the saprotrophic fungal community residing in the forest floor and employed molecular genetic approaches to determine if the slower decomposition rates resulted from down-regulation of the transcription of key lignocellulolytic genes, by a change in fungal community composition, or by a combination of the two mechanisms. Our results indicate that across four Acer-dominated forest stands spanning a 500-km transect, community-scale expression of the cellulolytic gene cbhI under elevated N deposition did not differ significantly from that under ambient levels of N deposition. In contrast, expression of the ligninolytic gene lcc was significantly down-regulated by a factor of 2-4 fold relative to its expression under ambient N deposition. Fungal community composition was examined at the most southerly of the four sites, in which consistently lower levels of cbhI and lcc gene expression were observed over a two-year period. We recovered 19 basidiomycete and 28 ascomycete rDNA 28S operational taxonomic units; Athelia, Sistotrema, Ceratobasidium and Ceratosebacina taxa dominated the basidiomycete assemblage, and Leotiomycetes dominated the ascomycetes. Simulated N deposition increased the proportion of basidiomycete sequences recovered from forest floor, whereas the proportion of ascomycetes in the community was significantly lower under elevated N deposition. Our results suggest that chronic atmospheric N deposition may lower decomposition rates through a combination of reduced expression of ligninolytic genes such as lcc, and compositional changes in the fungal community.

  12. Anthropogenic Decline of Ecosystem Services Threatens the Integrity of the Unique Hyrcanian (Caspian Forests in Northern Iran

    Directory of Open Access Journals (Sweden)

    Ardavan Zarandian

    2016-02-01

    Full Text Available The unique Hyrcanian (Caspian forests of northern Iran provide vital ecosystem services for local and global communities. We assess the status and trends of key ecosystem services in this region where native forest conversion has accelerated to make way for housing and farm development. This is a mountainous forested area that is valuable for both conservation and multiple human uses including recreation and farming. It contains globally significant natural habitats for in situ conservation of biological diversity. A rapid, qualitative, and participatory approach was used including interviews with local households and experts in combination with assessment of land use/cover remote sensing data to identify and map priority ecosystem services in the Geographic Information System (GIS. Based on the interests of the beneficiaries, eight priority services (food production, water supply, raw materials, soil conservation, water regulation, climate regulation, biodiversity, and recreation were identified and mapped. The results indicate the current typical spatial distribution of the provided services based on structural characteristics of the study landscape and their changing trends through a comparison of past, present and future land use, and land cover. Although food production and recreation have greatly increased in recent decades, the other services, in particular timber production, biodiversity, and water purification and supply are being gradually lost. The results of this study and of others elsewhere should raise awareness of ecosystem service status and trends and the value of examining these since they provide much of the information to inform natural resources policy and decision making. The declines in supply of key ecosystem services both within and outside the protected area are creating conflicts within communities as well as impacting on the integrity of the area and careful planning and conservation is required to provide win

  13. Impact of payments for environmental services and protected areas on local livelihoods and forest conservation in northern Cambodia.

    Science.gov (United States)

    Clements, Tom; Milner-Gulland, E J

    2015-02-01

    The potential impacts of payments for environmental services (PES) and protected areas (PAs) on environmental outcomes and local livelihoods in developing countries are contentious and have been widely debated. The available evidence is sparse, with few rigorous evaluations of the environmental and social impacts of PAs and particularly of PES. We measured the impacts on forests and human well-being of three different PES programs instituted within two PAs in northern Cambodia, using a panel of intervention villages and matched controls. Both PES and PAs delivered additional environmental outcomes relative to the counterfactual: reducing deforestation rates significantly relative to controls. PAs increased security of access to land and forest resources for local households, benefiting forest resource users but restricting households' ability to expand and diversify their agriculture. The impacts of PES on household well-being were related to the magnitude of the payments provided. The two higher paying market-linked PES programs had significant positive impacts, whereas a lower paying program that targeted biodiversity protection had no detectable effect on livelihoods, despite its positive environmental outcomes. Households that signed up for the higher paying PES programs, however, typically needed more capital assets; hence, they were less poor and more food secure than other villagers. Therefore, whereas the impacts of PAs on household well-being were limited overall and varied between livelihood strategies, the PES programs had significant positive impacts on livelihoods for those that could afford to participate. Our results are consistent with theories that PES, when designed appropriately, can be a powerful new tool for delivering conservation goals whilst benefiting local people. © 2014 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

  14. Life history attributes data for Arizona Grasshopper Sparrow (Ammodramus savannarum ammolegus) in Arizona 2013

    Science.gov (United States)

    Ruth, Janet M.

    2017-01-01

    Ammodramus savannarum ammolegus (commonly referred to as the Arizona Grasshopper Sparrow) occurs in the desert and plains grasslands of southeastern Arizona, southwestern New Mexico, and northern Sonora, Mexico. Although a subspecies of conservation concern, this data was produced as part of the first intensive study of its life history and breeding ecology, providing baseline data and facilitating comparisons with other North American Grasshopper Sparrow subspecies. This study is described in the publication listed in the larger work citation of this metadata record. 

  15. Spatial coexistence of American beech and sugar maple regeneration in post-harvest northern hardwood forests

    OpenAIRE

    Nelson, Andrew S.; Wagner, Robert G.

    2014-01-01

    International audience; & Context Fine scale regeneration patterns of coexistent spe-cies are influenced by regeneration mechanisms and microsite requirements. Spatial patterns may be either disjunct or over-lapping, which will determine competitive effects and microsite dominance, and future forest composition. & Aims Using American beech (Fagus grandifolia Ehrh.) and sugar maple (Acer saccharum Marshall) as an example, three hypotheses were tested: (1) random beech spatial patterns, (2) clu...

  16. Geophysical features influence the climate change sensitivity of northern Wisconsin pine and oak forests.

    Science.gov (United States)

    Tweiten, Michael A; Calcote, Randy R; Lynch, Elizabeth A; Hotchkiss, Sara C; Schuurman, Gregor W

    2015-10-01

    Landscape-scale vulnerability assessment from multiple sources, including paleoecological site histories, can inform climate change adaptation. We used an array of lake sediment pollen and charcoal records to determine how soils and landscape factors influenced the variability of forest composition change over the past 2000 years. The forests in this study are located in northwestern Wisconsin on a sandy glacial outwash plain. Soils and local climate vary across the study area. We used the Natural Resource Conservation Service's Soil Survey Geographic soil database and published fire histories to characterize differences in soils and fire history around each lake site. Individual site histories differed in two metrics of past vegetation dynamics: the extent to which white pine (Pinus strobus) increased during the Little Ice Age (LIA) climate period and the volatility in the rate of change between samples at 50-120 yr intervals. Greater increases of white pine during the LIA occurred on sites with less sandy soils (R² = 0.45, P climate (R² = 0.55, P change between samples was positively associated with LIA fire frequency (R² = 0.41, P change and rate-of-change volatility were associated with higher fire frequency. Over longer (multi-centennial) time frames, forest composition change, especially increased white pine, shifted most in sites with more soil moisture. Our results show that responsiveness of forest composition to climate change was influenced by soils, local climate, and fire. The anticipated climatic changes in the next century will not produce the same community dynamics on the same soil types as in the past, but understanding past dynamics and relationships can help us assess how novel factors and combinations of factors in the future may influence various site types. Our results support climate change adaptation efforts to monitor and conserve the landscape's full range of geophysical features.

  17. Fire-induced erosion and millennial-scale climate change in northern ponderosa pine forests.

    Science.gov (United States)

    Pierce, Jennifer L; Meyer, Grant A; Jull, A J Timothy

    2004-11-04

    Western US ponderosa pine forests have recently suffered extensive stand-replacing fires followed by hillslope erosion and sedimentation. These fires are usually attributed to increased stand density as a result of fire suppression, grazing and other land use, and are often considered uncharacteristic or unprecedented. Tree-ring records from the past 500 years indicate that before Euro-American settlement, frequent, low-severity fires maintained open stands. However, the pre-settlement period between about ad 1500 and ad 1900 was also generally colder than present, raising the possibility that rapid twentieth-century warming promoted recent catastrophic fires. Here we date fire-related sediment deposits in alluvial fans in central Idaho to reconstruct Holocene fire history in xeric ponderosa pine forests and examine links to climate. We find that colder periods experienced frequent low-severity fires, probably fuelled by increased understory growth. Warmer periods experienced severe droughts, stand-replacing fires and large debris-flow events that comprise a large component of long-term erosion and coincide with similar events in sub-alpine forests of Yellowstone National Park. Our results suggest that given the powerful influence of climate, restoration of processes typical of pre-settlement times may be difficult in a warmer future that promotes severe fires.

  18. Calcium and aluminum impacts on sugar maple physiology in a northern hardwood forest.

    Science.gov (United States)

    Halman, Joshua M; Schaberg, Paul G; Hawley, Gary J; Pardo, Linda H; Fahey, Timothy J

    2013-11-01

    Forests of northeastern North America have been exposed to anthropogenic acidic inputs for decades, resulting in altered cation relations and disruptions to associated physiological processes in multiple tree species, including sugar maple (Acer saccharum Marsh.). In the current study, the impacts of calcium (Ca) and aluminum (Al) additions on mature sugar maple physiology were evaluated at the Hubbard Brook Experimental Forest (Thornton, NH, USA) to assess remediation (Ca addition) or exacerbation (Al addition) of current acidified conditions. Fine root cation concentrations and membrane integrity, carbon (C) allocation, foliar cation concentrations and antioxidant activity, foliar response to a spring freezing event and reproductive ability (flowering, seed quantity, filled seed and seed germination) were evaluated for dominant sugar maple trees in a replicated plot study. Root damage and foliar antioxidant activity were highest in Al-treated trees, while growth-associated C, foliar re-flush following a spring frost and reproductive ability were highest in Ca-treated trees. In general, we found that trees on Ca-treated plots preferentially used C resources for growth and reproductive processes, whereas Al-treated trees devoted C to defense-based processes. Similarities between Al-treated and control trees were observed for foliar cation concentrations, C partitioning and seed production, suggesting that sugar maples growing in native forests may be more stressed than previously perceived. Our experiment suggests that disruption of the balance of Ca and Al in sugar maples by acid deposition continues to be an important driver of tree health.

  19. Profiles of carbon stocks in forest, reforestation and agricultural land, Northern Thailand

    Institute of Scientific and Technical Information of China (English)

    P. Pibumrung; N. Gajaseni; A. Popan

    2008-01-01

    A study was conducted to assess carbon stocks in various forms and land-use types and reliably estimate the impact of land use on C stocks in the Nam Yao sub-watershed (19°05'10"N, 100°37'02"E), Thailand. The carbon stocks of aboveground, soil organic and fine root within primary forest, reforestation and agricultural land were estimated through field data collection. Results revealed that the amount of total carbon stock of forests (357.62 ± 28.51 Mg·ha-1, simplified expression of Mg (carbon)·ha-1) was significantly greater (P< 0.05) than the reforestation (195.25 ±14.38 Mg·ha-1) and the agricultural land (103.10±18.24 Mg·ha-1). Soil organic carbon in the forests (196.24 ±22.81 Mg·ha-1) was also significantly greater (P< 0.05) than the reforestation (146.83± 7.22 Mg·ha-1) and the agricultural land (95.09 ± 14.18 Mg·ha-1). The differences in carbon stocks across land-use types are the primary consequence of variations in the vegetation biomass and the soil organic matter. Fine root carbon was a small fraction of carbon stocks in all land-use types. Most of the soil organic carbon and fine root carbon content was found in the upper 40-cm layer and decreased with soil depth. The aboveground carbon(soil organic carbon: fine root carbon ratios (ABGC: SOC: FRC), was 5:8:1, 2:8:1, and 3:50:1 for the forest, reforestation and agricultural land, respectively. These results indicate that a relatively large proportion of the C loss is due to forest conversion to agricultural land. However, the C can be effectively recaptured through reforestation where high levels of C are stored in biomass as carbon sinks, facilitating carbon dioxide mitigation.

  20. Carbon account of forest ecosystems as a fuzzy system: a case study for Northern Eurasia

    Science.gov (United States)

    Shvidenko, A.; Shchepashchenko, D.; Kraxner, F.; Maksyutov, S. S.

    2015-12-01

    We consider practicality of a verified account of Net Ecosystem Carbon Budget for forest ecosystems (FCA) that supposes reliable assessment of uncertainties, i.e. understanding "uncertainty of uncertainties". The FCA is a fuzzy (underspecified) system, of which membership function is inherently stochastic. Thus, any individually used method of FCA is not able to estimate structural uncertainties and usually reported "within method" uncertainties are inevitably partial. Attempting at estimation of "full uncertainties" of the studied system we follow the requirements of applied systems analysis integrating the major methods of terrestrial ecosystems carbon account, assessing the uncertainties "within method" for intermediate and final indicators of FCA with their following mutual constrains. Landscape-ecosystem approach (LEA) 1) serves for strict systems designing the account, 2) contains all relevant spatially distributed empirical and semi-empirical data and models, and 3) is presented in form of an Integrated Land Information System (ILIS). By-pixel parametrization of forest cover is provided by utilizing multi-sensor remote sensing data (12 RS products used) within GEO-wiki platform and other relevant information based on special optimization algorithms. Major carbon fluxes within the LEA (NPP, HR, disturbances etc.) are estimated based on fusion of empirical data with process-based elements by sets of regionally distributed models. Uncertainties within LEA are assessed for each module and at each step of the account. "Within method" results and uncertainties (including LEA, process-based models, eddy covariance, and inverse modelling) are harmonized based on the Bayesian approach. The above methodology have been applied to carbon account of Russian forests for 2000-2010; uncertainties of the FCA for individual years were estimated in limits of 25%. We discussed strengths and weaknesses of the approach, system requirements to different methods of FCA, information

  1. Landscape genetics of leaf-toed geckos in the tropical dry forest of northern Mexico.

    Science.gov (United States)

    Blair, Christopher; Jiménez Arcos, Victor H; Mendez de la Cruz, Fausto R; Murphy, Robert W

    2013-01-01

    Habitat fragmentation due to both natural and anthropogenic forces continues to threaten the evolution and maintenance of biological diversity. This is of particular concern in tropical regions that are experiencing elevated rates of habitat loss. Although less well-studied than tropical rain forests, tropical dry forests (TDF) contain an enormous diversity of species and continue to be threatened by anthropogenic activities including grazing and agriculture. However, little is known about the processes that shape genetic connectivity in species inhabiting TDF ecosystems. We adopt a landscape genetic approach to understanding functional connectivity for leaf-toed geckos (Phyllodactylus tuberculosus) at multiple sites near the northernmost limit of this ecosystem at Alamos, Sonora, Mexico. Traditional analyses of population genetics are combined with multivariate GIS-based landscape analyses to test hypotheses on the potential drivers of spatial genetic variation. Moderate levels of within-population diversity and substantial levels of population differentiation are revealed by FST and Dest. Analyses using structure suggest the occurrence of from 2 to 9 genetic clusters depending on the model used. Landscape genetic analysis suggests that forest cover, stream connectivity, undisturbed habitat, slope, and minimum temperature of the coldest period explain more genetic variation than do simple Euclidean distances. Additional landscape genetic studies throughout TDF habitat are required to understand species-specific responses to landscape and climate change and to identify common drivers. We urge researchers interested in using multivariate distance methods to test for, and report, significant correlations among predictor matrices that can impact results, particularly when adopting least-cost path approaches. Further investigation into the use of information theoretic approaches for model selection is also warranted.

  2. Landscape genetics of leaf-toed geckos in the tropical dry forest of northern Mexico.

    Directory of Open Access Journals (Sweden)

    Christopher Blair

    Full Text Available Habitat fragmentation due to both natural and anthropogenic forces continues to threaten the evolution and maintenance of biological diversity. This is of particular concern in tropical regions that are experiencing elevated rates of habitat loss. Although less well-studied than tropical rain forests, tropical dry forests (TDF contain an enormous diversity of species and continue to be threatened by anthropogenic activities including grazing and agriculture. However, little is known about the processes that shape genetic connectivity in species inhabiting TDF ecosystems. We adopt a landscape genetic approach to understanding functional connectivity for leaf-toed geckos (Phyllodactylus tuberculosus at multiple sites near the northernmost limit of this ecosystem at Alamos, Sonora, Mexico. Traditional analyses of population genetics are combined with multivariate GIS-based landscape analyses to test hypotheses on the potential drivers of spatial genetic variation. Moderate levels of within-population diversity and substantial levels of population differentiation are revealed by FST and Dest. Analyses using structure suggest the occurrence of from 2 to 9 genetic clusters depending on the model used. Landscape genetic analysis suggests that forest cover, stream connectivity, undisturbed habitat, slope, and minimum temperature of the coldest period explain more genetic variation than do simple Euclidean distances. Additional landscape genetic studies throughout TDF habitat are required to understand species-specific responses to landscape and climate change and to identify common drivers. We urge researchers interested in using multivariate distance methods to test for, and report, significant correlations among predictor matrices that can impact results, particularly when adopting least-cost path approaches. Further investigation into the use of information theoretic approaches for model selection is also warranted.

  3. Seedling Growth and Phosphorus Cycling in Northern Forest Soils Amended With Biochar and Wood Ash

    Science.gov (United States)

    Noyce, G. L.; Jones, T.; Fulthorpe, R.; Basiliko, N.

    2015-12-01

    Biochar may be a powerful soil amendment to reduce nutrient depletion in North American forests where long-term nitrogen deposition has led to phosphorus (P) limitation, but many effects of biochar in these ecosystems are still unknown. We performed a 12-week growth chamber experiment in which red pine (Pinus resinosa) and sugar maple (Acer saccharum) seedlings were grown in pots with soil from three Ontario forests and varying amounts of sugar maple biochar. Additionally, biochar effects were compared with the effects of wood ash, a forest biomass bioenergy by-product that may also be a beneficial soil amendment in these ecosystems. We assessed plant biomass, soil microbial biomass and phosphatase activity; additional chemical analyses of plant tissue and soils are ongoing. Biochar effects on seedling growth were not consistent across tree species, soil type, and addition rate. For sugar maple seedlings grown in sand and sandy-loam textured soils, biochar additions of 20 t ha-1 significantly (p = 0.03) decreased root biomass by 25 %, and the root-to-shoot ratio correspondingly declined, but this effect was not observed in a silty soil. For red pine seedlings, the same biochar addition rate slightly increased root biomass. Wood ash effects on biomass were similarly variable. For example, in the sandy soil, sugar maple root biomass was significantly lower after application of 16 t ash ha-1, but unchanged by rates of 4 or 40 t ash ha-1. Microbial biomass and soil phosphatase activity also varied by soil type. Phosphatase activity was significantly lower (p = 0.02) in soils with sugar maple compared to red pine, but there were no consistent biochar or ash effects across all soils and species. However, for red pine seedlings grown in silt, biochar significantly (p = 0.04) reduced the phosphatase activity compared to the control and ash soils. Overall, biochar may lessen P-limitation in forested ecosystems, but the suitability of biochar, and wood ash, for increasing P

  4. Measurements and simulation of forest leaf area index and net primary productivity in Northern China.

    Science.gov (United States)

    Wang, P; Sun, R; Hu, J; Zhu, Q; Zhou, Y; Li, L; Chen, J M

    2007-11-01

    Large scale process-based modeling is a useful approach to estimate distributions of global net primary productivity (NPP). In this paper, in order to validate an existing NPP model with observed data at site level, field experiments were conducted at three sites in northern China. One site is located in Qilian Mountain in Gansu Province, and the other two sites are in Changbaishan Natural Reserve and Dunhua County in Jilin Province. Detailed field experiments are discussed and field data are used to validate the simulated NPP. Remotely sensed images including Landsat Enhanced Thematic Mapper plus (ETM+, 30 m spatial resolution in visible and near infrared bands) and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER, 15m spatial resolution in visible and near infrared bands) are used to derive maps of land cover, leaf area index, and biomass. Based on these maps, field measured data, soil texture and daily meteorological data, NPP of these sites are simulated for year 2001 with the boreal ecosystem productivity simulator (BEPS). The NPP in these sites ranges from 80 to 800 gCm(-2)a(-1). The observed NPP agrees well with the modeled NPP. This study suggests that BEPS can be used to estimate NPP in northern China if remotely sensed images of high spatial resolution are available.

  5. Response of frugivorous primates to changes in fruit supply in a northern Amazonian forest.

    Science.gov (United States)

    Mourthé, I

    2014-08-01

    Few attempts have been made to understand how spatiotemporal changes in fruit supply influence frugivores in tropical forests. The marked spatiotemporal variation in fruit supply can affect frugivore abundance and distribution, but studies addressing the effects of this variation on primates are scarce. The present study aimed to investigate how the spatiotemporal distribution of fruits influences the local distribution of three frugivorous primates in the eastern part of the Maracá Ecological Station, a highly seasonal Amazonian rainforest. Specifically, it was hypothesised that primate distribution will track changes in fruit supply, resulting that sites with high fruit availability should be heavily used by primates. During a 1-year study, fruit supply (ground fruit surveys) and primate density (line-transects) were monitored in twelve 2 km-long transects at monthly intervals. Fruit supply varied seasonally, being low during the dry season. The density of Ateles belzebuth was positively related to fruit supply during fruit shortage, but Cebus olivaceus and Alouatta macconnelli did not follow the same pattern. The supply of Sapotaceae fruit was an important component determining local distribution of A. belzebuth during the overall fruit shortage. Highly frugivorous primates such as A. belzebuth respond to seasonal decline in fruit supply by congregating at places with high fruit supply in this forest, particularly, those with many individuals of species of Sapotaceae. This study underscores the importance of small-scale spatiotemporal changes of fruit supply as a key component of frugivorous primate ecology in highly seasonal environments.

  6. Carbon dynamics in aboveground coarse wood biomass of wetland forests in the northern Pantanal, Brazil

    Science.gov (United States)

    Schöngart, J.; Arieira, J.; Felfili Fortes, C.; Cezarine de Arruda, E.; Nunes da Cunha, C.

    2008-05-01

    This is the first estimation on carbon dynamics in the aboveground coarse wood biomass (AGWB) of wetland forests in the Pantanal, located in Central Southern America. In four 1-ha plots in stands characterized by the pioneer species Vochysia divergens Pohl (Vochysiaceae) forest inventories (trees ≥10 cm diameter at breast height, DBH) have been performed and converted to predictions of AGWB by five different allometric models using two or three predicting parameters (DBH, tree height, wood density). Best prediction has been achieved using allometric equations with three independent variables. Carbon stocks (50% of AGWB) vary from 7.4 to 100.9 Mg C ha-1 between the four stands. Carbon sequestration differs 0.50-4.24 Mg C ha-1 yr-1 estimated by two growth models derived from tree-ring analysis describing the relationships between age and DBH for V. divergens and other tree species. We find a close correlation between estimated tree age and C-stock, C-sequestration and C-turnover (mean residence of C in AGWB).

  7. Spatial heterogeneity of factors influencing forest fires size in northern Mexico

    Institute of Scientific and Technical Information of China (English)

    Gustavo Perez-Verdin; Marco Antonio Marquez-Linares; Maricela Salmeron-Macias

    2014-01-01

    In Mexico, forest fires are strongly influenced by environ-mental, topographic, and anthropogenic factors. A government-based database covering the period 2000-2011 was used to analyze the spatial heterogeneity of the factors influencing forest fire size in the state of Durango, Mexico. Ordinary least squares and geographically weighted regression models were fit to identify the main factors as well as their spatial influence on fire size. Results indicate that fire size is greatly affected by distance to roads, distance to towns, precipitation, temperature, and a population gravity index. The geographically weighted model was better than the ordinary least squares model. The improvement of the former is due to the influence of factors that were found to be non-stationary. These results suggest that geographic location determines the influence of a factor on fire size. While the models can be greatly improved with additional information, the study suggests the need to adopt fire management policies to more efficiently reduce the effect of anthropogenic factors. These policies may include more training for landowners who use fire for clearing, closure of roads, application of thinning, prescribed burning, and fire breaks in perimeters adjacent to roads.

  8. Monitoring endophyte populations in pine plantations and native oak forests in Northern Spain

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Alvarez, P.; Martin-Garcia, J.; Rodriguez-Ceinos, S.; Diez, J. J.

    2012-07-01

    The replacement of native forest with plantations of other species may have important impacts on ecosystems. Some of these impacts have been widely studied, but very little is known about the effects on fungal communities and specifically endo phytic fungi. In this study, endophyte assemblages in pine plantations (Pinus sylvestris, P. nigra and P. pinaster) and native oak forests (Quercus pyrenaica) in the north of the province of Palencia (Spain) were analyzed. For this purpose, samples of needles/leaves and twigs were collected from three trees in each of three plots sampled per host species. The samples were later processed in the laboratory to identify all of the endo phytic species present. In addition, an exhaustive survey was carried out of the twelve sites to collect data on the environmental, crown condition, dendrometric and soil variables that may affect the distribution of the fungi. The endophyte assemblages isolated from P. sylvestris and P. nigra were closely related to each other, but were different from those isolated from P. pinaster. The endophytes isolated from Q. pyrenaica were less closely related to those from the other hosts, and therefore preservation of oak stands is important to prevent the loss of fungal diversity. Finally, the distribution of the endophyte communities was related to some of the environmental variables considered. (Author) 42 refs.

  9. Long term implications of fire to soil C content and soil CO2 efflux in northern boreal forests

    Science.gov (United States)

    Koster, Kajar; Berninger, Frank; Pumpanen, Jukka

    2014-05-01

    Fire is the primary process which organizes the physical and biological attributes of the boreal biome and influences energy flows and biogeochemical cycles, particularly the carbon (C) cycle. Especially the soil organic matter pool in boreal forests is an important C storage with a long C turnover time, but fire frequencies that are expected to increase with changing climate, can change that. We compared the initial recovery of C pools and CO2 efflux following fire disturbance in Scots pine (Pinus sylvesteris) stands in the northern boreal forests, of eastern Lapland, Värriö Strict Nature Reserve, Finland (67°46' N, 29°35' E). The sites are situated north of the Arctic Circle, near to the northern timberline at an average of 300 m altitude. We have established 8 sample areas (with two replicate plots in each) in a chronosequence of 4 age classes (2 to 152 years since the last fire). The chronosequence consisted of four types of areas: (i) fire 2 years ago old areas, (ii) fire 42 years ago, (iii) fire around 60 years ago, (iv) fire 152years ago. The total C contents in the first 10 cm of the topsoil were highest on old areas (fire 150 years ago) and lowest on new areas (fire 2-40 years ago). The total C pool at the old site was 2411 g m-2. The area where the fire was 2 years ago had the lowest total C pools, 1474 g m-2 respectively. The lowest C pools were measured from area where the fire was 60 years ago, and from B horizon. The highest C pools were measured on old areas from top soil horizons (consisting of decomposing litter). When we compared the total C pools, the newly burned areas (areas where the fire was 2 - 40 years ago) formed one group (had similar values of total C) and old areas (areas where the fire was 60-150 years ago) formed another group with similar values. These results are also correlating to the soil respiration measurements. Soil CO2 efflux was lowest straight after the fire (0.042 mg CO2 m-2 s-1) and it reached a stable level of around

  10. Nutrient distribution and accumulation patterns of natural secondary forests in the Loess Plateau of Shanxi Province, northern China

    Institute of Scientific and Technical Information of China (English)

    Xiaojuan ZHANG; Tianxing WEI; Libo JING; Na YIN; Yanhui LIU

    2009-01-01

    We studied the biomass and its allocation in natural secondary forests, as well as the amounts, accumulation and distribution of nutrient elements (N, P, K, Ca and Mg) in sample plots established in the Loess Plateau in Shanxi Province, northern China. The results show that biomass in natural secondary forests amounted to 36.09 t/hm2,. of which the tree layer accounted for 46%, the shrub layer for 29%, the herb layer for 13% and the litter layer for 12%. The total storage of the five nutrient elements is 1089.82 kg/hm2. Nutrient storage in the tree layer is the largest, at 41%. The sequence of storage of the elements varied among different layers and is given as follows: shrub layer 31.27%, herb layer 12.55% and litter layer 15.36%. The accumulation of nutrient elements in the tree layer, ordered from high to low, is: branches > roots > stems > bark > leaves. The total storage of the five nutrient elements in the soil is 634.97 t/hm2, where the accumulation of the nutrients accounts for 95.32% (N), 99.64% (P), 99.91% (K), 99.84% (Ca) and 99.95% (Mg) of the total amounts. The accumulation coefficients of different organs in the tree layer are, from high to low: leaves > branches > roots > bark > stems. The accumulation coefficients in the different layers are listed as follows: shrub layer > tree layer > herb layer and for the elements as: N > P > Ca > K > Mg.

  11. Simulating soil organic carbon stock as affected by land cover change and climate change, Hyrcanian forests (northern Iran).

    Science.gov (United States)

    Soleimani, Azam; Hosseini, Seyed Mohsen; Massah Bavani, Ali Reza; Jafari, Mostafa; Francaviglia, Rosa

    2017-12-01

    Soil organic carbon (SOC) contains a considerable portion of the world's terrestrial carbon stock, and is affected by changes in land cover and climate. SOC modeling is a useful approach to assess the impact of land use, land use change and climate change on carbon (C) sequestration. This study aimed to: (i) test the performance of RothC model using data measured from different land covers in Hyrcanian forests (northern Iran); and (ii) predict changes in SOC under different climate change scenarios that may occur in the future. The following land covers were considered: Quercus castaneifolia (QC), Acer velutinum (AV), Alnus subcordata (AS), Cupressus sempervirens (CS) plantations and a natural forest (NF). For assessment of future climate change projections the Fifth Assessment IPCC report was used. These projections were generated with nine Global Climate Models (GCMs), for two Representative Concentration Pathways (RCPs) leading to very low and high greenhouse gases concentration levels (RCP 2.6 and RCP 8.5 respectively), and for four 20year-periods up to 2099 (2030s, 2050s, 2070s and 2090s). Simulated values of SOC correlated well with measured data (R(2)=0.64 to 0.91) indicating a good efficiency of the RothC model. Our results showed an overall decrease in SOC stocks by 2099 under all land covers and climate change scenarios, but the extent of the decrease varied with the climate models, the emissions scenarios, time periods and land covers. Acer velutinum plantation was the most sensitive land cover to future climate change (range of decrease 8.34-21.83tCha(-1)). Results suggest that modeling techniques can be effectively applied for evaluating SOC stocks, allowing the identification of current patterns in the soil and the prediction of future conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Report of the OCVCI-PAPRICAN forest-based chemicals biorefinery Northern Ontario Commercialization Initiative workshop

    Energy Technology Data Exchange (ETDEWEB)

    Magdzinski, L. (ed.)

    2007-07-01

    This workshop was held to establish commercial processes for the generation of sustainable chemical feedstock from pulp mills. The workshop was attended by over 60 participants from the pulp and paper industry as well as members of the chemical, forestry, and industrial biotechnology industries. Representatives from governments and academic institutions also attended. Links were established between the Ontario forest sector and the Ontario chemical and and polymer sectors. The workshop presented a range of topics for discussion among participants, including issues related to the development of industrial chemicals from pulp mills and methods of sustainably extracting chemicals from hemicellulose. Issues related to the development of bioplastics from pulp production were discussed as well as new developments in wood-derived pharmaceuticals and nutraceuticals. Ontario forestry resources were reviewed, and a Paprican biorefinery agenda was presented. Current pulp mill bio-based chemicals were discussed, and sustainable feedstocks for the production of chemicals were identified. Industrial bioconversion processes were also outlined.

  13. Testing the Framework Species Method for Forest Restoration in Chiang Mai, Northern Thailand

    Directory of Open Access Journals (Sweden)

    Prasit WANGPAKAPATTANAWONG

    2008-01-01

    Full Text Available The framework species method of reforestation, developed by FORRU (Forest Restoration Research Unit has been used successfully to restore evergreen forest on degraded former agricultural sites in Doi Suthep-Pui National Park, Chiang Mai province, Thailand. This paper reports 3 year results of an attempt to duplicate the FORRU reforestation techniques at Ban Toong Yah, Mae Chaem district, at a similar elevation as FORRU’s original plots at Ban Mae Sa Mai, Mae Rim district. Twenty species of framework tree seedlings were planted in June 2002. The 2 year results indicate that the seedlings achieved lower survival rates than at the FORRU’s original site. Height growth, root collar diameter, and crown width were also lower. Some seedlings died because they were trampled by cows, which also ate some of the seedlings. However, several sapling species, such as Ficus fistulosa and Phyllanthus emblica, were able to produce new shoots from their axillary buds, after having been browsed by cows. In 2004, 5 well-performed species: Castanopsis tribuloides, Ficus fistulosa, Hovenia dulcis, Ostodes paniculata and Prunus cerasoides, were selected along with 12 never-planted species to be planted in June. The results indicate that the seedlings achieved lower survival rates than at the FORRU’s original site. The seedlings achieved an average survival rate of about 50 % after the first growing season. The exposed, windy environment of the planting site might also account for lower than expected growth and survival rates. The FORRU’s recommended methods of site preparation using herbicide and weed suppression using cardboard mulch may be employed to improve seedling survival and growth on this site.

  14. Dreamy Draw Dam - Master Plan and Feature Design, New River and Phoenix City Streams, Arizona.

    Science.gov (United States)

    1981-09-01

    and New and Apr. 1983 Agua Fria River below the Arizona Canal Diversion Channel Part 5 - Arizona Canal Diversion Dec. 1983 Channel (including Cave...basin and can be tapped for potable water for recreation use. Electric lines are located approximately 2 miles from the basin at 19th Street and Northern

  15. Examining soil erosion and nutrient accumulation in forested and agriculture lands of the low mountainous area of Northern Vietnam

    Science.gov (United States)

    Pham, A. T.; Gomi, T.; Takahisa, F.; Phung, K. V.

    2011-12-01

    We examined soil erosion and nutrient accumulations in the Xuanmai area located in the low mountainous region of Northern Vietnam, based on field investigations and remote sensing approaches. The study area had been degraded by land-use change from forest to agriculture in the last 20 years. In contrast, around the study area, the Vietnam government promoted reforestation projects. Such changes in land-use conditions, which may or may not be associated with vegetation ground cover conditions, potentially alter soil erosion and nutrient accumulation. We selected 10 dominant land-use types including forested land (e.g., Pinus massoniana and Acacia mangium plantation) agriculture land (e.g., Cassava), and bare land. We established three 1 x 1 m plots in each land-use type in September 2010. Vegetation biomass, litter cover, soil erosion (height of soil pedestal), and soil physical (soil bulk density and particle size distribution) and chemical properties (Total soil carbon, nitrate, and phosphorus) were measured. Height of soil pedestal can be a record of soil erosion by rain splash during rainy periods from April to August (prior to our field study). We also conducted remote sensing analysis using Landsat TM images obtained in 1993, 2000, and 2007 for identifying temporal patterns of land-use types. We found that the intensity of soil erosion depended primary on current vegetation ground cover condition with no regard of land-use. Hence, nutrient accumulation varied among vegetation ground cover and soil erosion. Remote sensing analysis suggested that shrub and bare lands had been altered from forested land more recently. Our finding suggested that variability of soil nutrient conditions can be associated with long-term soil erosion and production processes. Findings of our study are that: (1) current vegetation and litter ground cover affected the amount of surface soil erosion, and (2) legacy of land-use can be more critical for soil nutrient accumulation. Both

  16. Integration of Volterra model with artificial neural networks for rainfall-runoff simulation in forested catchment of northern Iran

    Science.gov (United States)

    Kashani, Mahsa H.; Ghorbani, Mohammad Ali; Dinpashoh, Yagob; Shahmorad, Sedaghat

    2016-09-01

    Rainfall-runoff simulation is an important task in water resources management. In this study, an integrated Volterra model with artificial neural networks (IVANN) was presented to simulate the rainfall-runoff process. The proposed integrated model includes the semi-distributed forms of the Volterra and ANN models which can explore spatial variation in rainfall-runoff process without requiring physical characteristic parameters of the catchments, while taking advantage of the potential of Volterra and ANNs models in nonlinear mapping. The IVANN model was developed using hourly rainfall and runoff data pertaining to thirteen storms to study short-term responses of a forest catchment in northern Iran; and its performance was compared with that of semi-distributed integrated ANN (IANN) model and lumped Volterra model. The Volterra model was applied as a nonlinear model (second-order Volterra (SOV) model) and solved using the ordinary least square (OLS) method. The models performance were evaluated and compared using five performance criteria namely coefficient of efficiency, root mean square error, error of total volume, relative error of peak discharge and error of time for peak to arrive. Results showed that the IVANN model performs well than the other semi-distributed and lumped models to simulate the rainfall-runoff process. Comparing to the integrated models, the lumped SOV model has lower precision to simulate the rainfall-runoff process.

  17. Investigation into High Barmah Forest Virus Disease Case Numbers Reported in the Northern Territory, Australia in 2012-2013.

    Science.gov (United States)

    Kurucz, Nina; Markey, Peter; Draper, Anthony; Melville, Lorna; Weir, Richard; Davis, Steven; Warchot, Allan; Boyd, Rowena; Stokeld, Danielle

    2016-02-01

    Between October 2012 and October 2013, unprecedented high numbers of Barmah Forest virus (BFV) disease cases were reported in the Northern Territory (NT). An investigation was launched by the NT Department of Health in cooperation with the Department of Primary Industry and Fisheries and the Department of Land Resource Management to investigate possible causes for this phenomenon. The investigation included virus isolations from mosquitoes collected in Darwin urban areas, BFV antibody testing in peri-urban small mammals and a human BFV disease case series investigation of recent cases. No BFV was isolated from the 4641 mosquitoes tested, none of the mammals tested positive for BFV antibodies, and the high BFV disease case numbers did not correlate with the relatively low mosquito vector numbers trapped in 2012-2013. It was estimated that up to 89% of the 79 human cases investigated did not have an acute arboviral illness and therefore had tested falsely positive. An Alere PanBio BFV immunoglobulin M enzyme-linked immunosorbent assay test kit is generally used to test for BFV, with the BFV disease case definition based on immunoglobulin M positives only. Other jurisdictions in Australia also reported high numbers of BFV disease cases, with the majority of the cases suspected to be false positives. Therefore, current testing methods need to be revised to reflect the true numbers of BFV disease cases occurring in Australia and to provide correct diagnoses for patients.

  18. Host plant phenology affects performance of an invasive weevil, Phyllobius oblongus (Coleoptera: Curculionidae), in a northern hardwood forest.

    Science.gov (United States)

    Coyle, David R; Jordan, Michelle S; Raffa, Kenneth F

    2010-10-01

    We investigated how host plant phenology and plant species affected longevity, reproduction, and feeding behavior of an invasive weevil. Phyllobius oblongus L. (Coleoptera: Curculionidae) is common in northern hardwood forests of the Great Lakes Region. Adults emerge in spring, feed on foliage of woody understory plants, and oviposit in the soil. Preliminary data indicate that adults often feed on sugar maple, Acer saccharum Marshall, foliage early in the season, then feed on other species such as raspberry, Rubus spp. Whether this behavior reflects temporal changes in the quality of A. saccharum tissue or merely subsequent availability of later-season plants is unknown. We tested adult P. oblongus in laboratory assays using young (newly flushed) sugar maple foliage, old (2-3 wk postflush) sugar maple foliage, and raspberry foliage. Raspberry has indeterminate growth, thus always has young foliage available for herbivores. Survival, oviposition, and leaf consumption were recorded. In performance assays under no-choice conditions, mated pairs were provided one type of host foliage for the duration of their lives. In behavioral choice tests, all three host plants were provided simultaneously and leaf area consumption was compared. Adults survived longer on and consumed greater amounts of young maple and raspberry foliage than old maple foliage. P. oblongus preferred young maple foliage to old maple foliage early in the season, however, later in the growing season weevils showed less pronounced feeding preferences. These results suggest how leaf phenology, plant species composition, and feeding plasticity in host utilization may interact to affect P. oblongus population dynamics.

  19. Asymmetric warming significantly affects net primary production, but not ecosystem carbon balances of forest and grassland ecosystems in northern China.

    Science.gov (United States)

    Su, Hongxin; Feng, Jinchao; Axmacher, Jan C; Sang, Weiguo

    2015-03-13

    We combine the process-based ecosystem model (Biome-BGC) with climate change-scenarios based on both RegCM3 model outputs and historic observed trends to quantify differential effects of symmetric and asymmetric warming on ecosystem net primary productivity (NPP), heterotrophic respiration (Rh) and net ecosystem productivity (NEP) of six ecosystem types representing different climatic zones of northern China. Analysis of covariance shows that NPP is significant greater at most ecosystems under the various environmental change scenarios once temperature asymmetries are taken into consideration. However, these differences do not lead to significant differences in NEP, which indicates that asymmetry in climate change does not result in significant alterations of the overall carbon balance in the dominating forest or grassland ecosystems. Overall, NPP, Rh and NEP are regulated by highly interrelated effects of increases in temperature and atmospheric CO2 concentrations and precipitation changes, while the magnitude of these effects strongly varies across the six sites. Further studies underpinned by suitable experiments are nonetheless required to further improve the performance of ecosystem models and confirm the validity of these model predictions. This is crucial for a sound understanding of the mechanisms controlling the variability in asymmetric warming effects on ecosystem structure and functioning.

  20. Regional and forest-level estimates of carbon stored in harvested wood products from the United States Forest Service Northern Region, 1906-2010

    Science.gov (United States)

    N. Anderson; J. Young; K. Stockmann; K. Skog; S. Healey; D. Loeffler; J.G. Jones; J. Morrison

    2013-01-01

    Global forests capture and store significant amounts of CO2 through photosynthesis. When carbon is removed from forests through harvest, a portion of the harvested carbon is stored in wood products, often for many decades. The United States Forest Service (USFS) and other agencies are interested in accurately accounting for carbon flux associated with harvested wood...

  1. Analysis of forest fires causes and their motivations in northern Algeria: the Delphi method

    Directory of Open Access Journals (Sweden)

    Meddour-Sahar O

    2013-06-01

    Full Text Available Forest fires in Algeria are mostly human-caused and result from local social behavior, whether voluntary (arson or involuntary (negligence. Understanding the reasons why fires start is, therefore, a crucial factor in preventing or reducing their incidence, developing significant prevention efforts and designing specific fire prevention campaigns. The Delphi method is a promising tool for improving knowledge about how fire starts and why, and above all helps reduce the number of fires started by unknown causes, the majority type in Algeria. The Delphi method uses a set of procedures for eliciting and refining the opinions of a panel of experts on a particular subject of interest. This method was used in three case studies, in coastal or inner wilayas (provinces selected from a highly fire-prone area in north-central Algeria. Results showed the traditional use of fire in agriculture and forestry, in situations related to land use changes and in interpersonal conflicts are the major causes of voluntary fires. For involuntary events (negligence, experts unanimously identified the importance of the restart of fire, caused by fire crews who do not ensure the mopping up of controlled fires (91.49% and the negligent use of agricultural fires, particularly stubble burning (80.14%. For voluntary fires (arson, results highlight the importance of fires set for land use changes (77.30%, pyromania (67.38% and honey gathering (62.41%. Illegal dumping and burning of garbage was also mentioned by responders in all study-areas.

  2. Mercury in coniferous and deciduous upland forests in northern New England, USA: implications of climate change

    Science.gov (United States)

    Richardson, J. B.; Friedland, A. J.

    2015-11-01

    Climatic changes in the northeastern US are expected to cause coniferous stands to transition to deciduous stands over the next hundred years. Mercury (Hg) sequestration in forest soils may change as a result. In order to understand potential effects of such a transition, we studied aboveground vegetation and soils at paired coniferous and deciduous stands on eight mountains in Vermont and New Hampshire, USA. Organic horizons at coniferous stands accumulated more total Hg (THg; 42 ± 6 g ha-1) than deciduous stands (30 ± 4 g ha-1). Total Hg pools in the mineral horizons were similar for coniferous (46 ± 8 g ha-1) and deciduous stands (45 ± 7 g ha-1). Soil properties (C, % clay, and pH) explained 56 % of the variation in mineral soil Hg concentration when multiply regressed. Foliar and bole wood Hg concentrations were generally greater for coniferous species than deciduous species. Using allometric equations, we estimated that aboveground accumulation of Hg in foliage and woody biomass was similar between vegetation types but that coniferous stands have significantly smaller annual litterfall fluxes (0.03 g ha-1 yr-1) than deciduous stands (0.24 g ha-1 yr-1). We conclude that organic horizon Hg accumulation is influenced by vegetation type but mineral horizon Hg accumulation is primarily controlled by soil properties. Further investigations into the effect of vegetation type on volatilization, atmospheric deposition, and leaching rates are needed to constrain regional Hg cycling rates.

  3. Relationships between Structure, Composition, and Dynamics of the Pristine Northern Boreal Forest and Air Temperature, Precipitation, and Soil Texture in Quebec (Canada

    Directory of Open Access Journals (Sweden)

    Louis Duchesne

    2009-01-01

    Full Text Available This study reports on the contemporary structure, composition, and dynamics of the pristine northern boreal forest in Quebec, Canada, associated with air temperature, precipitation, and soil texture, using 147 permanent sample plots located at the limit of continuous forest in Quebec. The results show that tree species composition of stands is associated with stand age, soil texture, air temperature, and precipitation regime. After establishment of the pioneer cohort, the postsuccessional stand dynamics differed among temperature and precipitation regimes, probably because of their influence on tree growth. Our results support the hypothesis that shifts in forest composition related to stand dynamics and the subsequent senescing phase associated with the old growth stage generally occur sooner and proceed faster on more fertile sites due to quicker growth and the subsequent earlier mortality of pioneer species. This study suggests that climate warming should accelerate the successional dynamics of these ecosystems through its positive influence on tree growth.

  4. Biological and functional diversity of bird communities in natural and human modified habitats in Northern Flank of Knuckles Mountain Forest Range, Sri Lanka

    Directory of Open Access Journals (Sweden)

    KALYA SUBASINGHE

    2014-10-01

    Full Text Available Subasinghe K, Sumanapala AP. 2014. Biological and functional diversity of bird communities in natural and human modified habitats in Northern Flank of Knuckles Mountain Forest Range, Sri Lanka. Biodiversitas 15: 200-205. The Knuckles Mountain Forest Range (KMFR has a complex mosaic of natural and human modified habitats and the contribution of these habitats to the biological and functional diversities has not been deeply studied. Present study investigated both of these diversities in five habitat types (two natural habitats: Sub-montane forest and Pitawala Patana grassland; three modified habitats: cardamom, pinus and abandoned tea plantations in Northern Flank of KMFR using birds as the indicator group. Bird communities were surveyed using point count method. A total of 1,150 individuals belonging to 56 species were observed. The highest species richness was reported from the cardamom plantation where as sub-montane forest had the highest feeding guild diversity in terms of Shannon Weiner index. The abandoned tea plantation and the Pitawala Patana grasslands with fairly open habitats, showed relatively lower levels of feeding guild diversities. It is clear that the structurally complex habitats contribute more to the area’s biological and functional diversities and need to be taken into consideration when developing conservation plans.

  5. Effects of single-tree selection harvesting on hymenopteran and saproxylic insect assemblages in the canopy and understory of northern temperate forests

    Institute of Scientific and Technical Information of China (English)

    Sandy M.Smith; Nurul Islam; M.Isabel Bellocq

    2012-01-01

    Insects respond to changes in microhabitat caused by canopy disturbance,and thus can be used to examine the ecological impacts of harvesting.Single-tree selection harvesting is the most common silvicultural system used to emulate local small-scale natural disturbance and maintain uneven-aged forest structure in temperate forests.Here,we test for differences in richness,abundance,and composition of hymenopteran and saproxylic insect assemblages at four different taxon levels (selected insect orders; and all hymenopteran families,and braconid subfamilies and morphospecies) between the canopy and understory of unharvested and single-tree selection harvested sites in a northern temperate forest from central Canada.Harvesting had no effect on insect assemblage richness,composition or abundance at the three highest taxon levels (order,family and subfamily).Similarly,richness and abundance at the lowest-taxon level (braconid morphospecies) were similar,although composition differed slightly between unharvested and harvested stands.Insect assemblages were vertically stratified,with generally higher abundance (for Diptera,Hymenoptera,some hymenopteran families and braconid subfamilies) and richness (for braconid morphospecies) in the understory than the canopy.In particular,composition of the braconid morphospecies assemblage showed relatively low similarity between the understory and canopy.Single-tree selection harvesting appears to influence wood-associated insect taxa only subtly through small changes in community composition at the lowest taxon level,and thus is recommended as a conservative approach for managing these northern temperate forests.

  6. Bagley Fire Sediment Study: Shasta-Trinity National Forest, Eastern Klamath Mountains, Northern California

    Science.gov (United States)

    Bachmann, S.; De La Fuente, J. A.; Hill, B.; Mai, C.; Mikulovsky, R. P.; Mondry, Z.; Rust, B.; Young, D.

    2013-12-01

    The US Forest Service is conducting a study of sediment mobilization, transport, and deposition on the Bagley Fire, which burned about 18,000 hectares in late summer, 2012, on the Shasta-Trinity National Forest, south of McCloud, CA. The fire area is in steep terrain of the Eastern Klamath Mountains that are underlain primarily by metasedimentary rock. The watersheds affected drain into the headwaters of Squaw Creek, along with small streams tributary to the McCloud and Pit Rivers, all of which flow into Shasta Lake Reservoir. In November and December of 2012, intense storms occurred over the fire area with estimated return intervals of 25-50 years, based on 4-day storm totals in ranging from 38 to 56 cm. The Squaw Creek storm response was unique for this area, in that it remained turbid for about 2 months following the storms. Subsequent small storms through June, 2013 have also generated prolonged turbidity. This may be attributable to the remobilization of fine particles temporarily stored in the channel network. Preliminary observations from field reconnaissance include the following: a) Erosional processes were dominated by sheet, rill, and gully erosion, and the resulting sediment delivered to channels was rich in fine particles and gravels; b) Landslides were infrequent, and as a result, a limited amount of large rock and logs were delivered to channels; c) Sediment laden flows occurred in most burned low order channels, but classic debris flows, those scouring all vegetation from channel bottoms, were very uncommon; d) Most road stream crossing culverts failed in high severity burn areas; e) Low gradient stream reaches in Squaw Creek were aggraded with fine sediment; f) Sustained high levels of turbidity occurred in the main stem of Squaw Creek. The goals of this study are to characterize relative roles of surface erosion, landslides, and debris flows in delivering sediment to streams after the fire, and if possible, to develop a rough sediment budget

  7. Mercury in coniferous and deciduous upland forests in Northern New England, USA: implications from climate change

    Directory of Open Access Journals (Sweden)

    J. B. Richardson

    2015-07-01

    Full Text Available Climatic changes in the northeastern US are expected to cause coniferous stands to transition to deciduous stands over the next hundred years. Mercury (Hg sequestration in forest soils may change as a result. In order to understand potential effects of this transition, we studied aboveground vegetation and soils at paired coniferous and deciduous stands on eight mountains in Vermont and New Hampshire, US. Organic horizons at coniferous stands accumulated more Total Hg (THg (42 ± 6 g ha−1 than deciduous stands (30 ± 4 g ha−1. Total Hg pools in the mineral horizons were similar for coniferous (46 ± 8 g ha−1 and deciduous stands (45 ± 7 g ha−1. Soil properties (C, % clay, and pH explained 56 % of the variation in mineral soil Hg concentration when multiple regressed. Foliar and bole wood Hg concentrations were generally greater for coniferous species than deciduous species. We estimated Hg mean residence time (MRT in the organic and mineral horizons at coniferous and deciduous stands using a simple two-box model. Organic horizon MRT were longer at coniferous stands (183 ± 44 yr than deciduous stands (65 ± 15 yr. Mineral soil horizon MRT values were also longer for coniferous stands (386 ± 57 yr than for deciduous stands (188 ± 27 yr. We concluded that organic horizon Hg accumulation is influenced by vegetation type but mineral horizons are primarily affected by soil properties. Further investigations into the effect of vegetation type on volatilization, atmospheric deposition, and leaching rates are needed to constrain regional Hg cycling rates.

  8. Local consequences of applying international norms: differences in the application of forest certification in northern Sweden, northern Finland, and northwest Russia

    NARCIS (Netherlands)

    Keskitalo, E.C.H.; Sandstrom, C.; Tysiachniouk, M.S.; Johansson, J.

    2009-01-01

    Forest certification, developed in the early 1990s, is a process in which independent assessors grant use of the certification label to producers who meet certain environmental and social criteria set for their forest products. This label was quickly seen to offer a market advantage and to signal co

  9. Growth of Fagus in transition zones of forest and soil on the western slope of Mt. Chokai, northern Japan

    Science.gov (United States)

    Kato, S.; Watanabe, M.

    2012-04-01

    A wide transition zone for forest structure is expected to distribute on the gentle slope of western side of Mt. Chokai ,Yamagata prefecture, northern Japan (N39° 05'57", E140°02'55"). The annual mean temperature and total precipitation at summit (2,059 m asl.) are 0.5° C and 3,285mm, respectively. The parent materials of the soils are weathered Andesite associated with non-tephric loess deposits transported from continental China. Representative sites were selected in forests of Quercus mongolica and Fagus crenata to examine characteristics of transition zones of vegetation and soil in the western slope of Mt. Chokai with concern on the growth of Fagus in transition zones. Surveys on vegetation profile and projection diagram of canopy for each site (10-10m plots) were carried out in 7 sites selected along altitudinal sequence on the western slope of Mt. Chokai; Ch1-7: 550-1,100m asl.. Growth rate of Fagus was estimated by the measurement of tree rings from increment core samples. Timber volume of Fagus at each point was calculated based on diameter of breast height; DBH as an indicator of tree biomass. Soil profiles were observed at the above 7 sites and soil samples were collected from each horizon. As for soil analyses, soil pH (H2O, KCl, NaF) values were measured by the glass electrode method in the suspension mixture of soil with a 2.5 times volume of H2O or 1N KCl and 50 times volume of 4% NaF. Pyrophosphate, acid oxalate and dithionite-citrate extractable Al (Alp, Alo, Ald), Fe (Feo, Fed) and Si (Sio, Sid) were measured by ICP-AES. The content of exchangeable Al (AlEX) was obtained by titration of extract with 1N KCl. Sclerotia formed by species of Cenococcum, ectomycorrhizal fungi, were collected for grains of diameter larger than 0.5mm from wet samples. Sclerotia content was obtained by weight (mg g-1 soil). Due to intensive base leaching under extremely high precipitation and the mineralogical properties, Ah and Ae horizons of all profiles had low soil

  10. An economic analysis of mobile pyrolysis for northern New Mexico forests.

    Energy Technology Data Exchange (ETDEWEB)

    Brady, Patrick D.; Brown, Alexander L.; Mowry, Curtis Dale; Borek, Theodore Thaddeus, III

    2011-12-01

    In the interest of providing an economically sensible use for the copious small-diameter wood in Northern New Mexico, an economic study is performed focused on mobile pyrolysis. Mobile pyrolysis was selected for the study because transportation costs limit the viability of a dedicated pyrolysis plant, and the relative simplicity of pyrolysis compared to other technology solutions lends itself to mobile reactor design. A bench-scale pyrolysis system was used to study the wood pyrolysis process and to obtain performance data that was otherwise unavailable under conditions theorized to be optimal given the regional problem. Pyrolysis can convert wood to three main products: fixed gases, liquid pyrolysis oil and char. The fixed gases are useful as low-quality fuel, and may have sufficient chemical energy to power a mobile system, eliminating the need for an external power source. The majority of the energy content of the pyrolysis gas is associated with carbon monoxide, followed by light hydrocarbons. The liquids are well characterized in the historical literature, and have slightly lower heating values comparable to the feedstock. They consist of water and a mix of hundreds of hydrocarbons, and are acidic. They are also unstable, increasing in viscosity with time stored. Up to 60% of the biomass in bench-scale testing was converted to liquids. Lower ({approx}550 C) furnace temperatures are preferred because of the decreased propensity for deposits and the high liquid yields. A mobile pyrolysis system would be designed with low maintenance requirements, should be able to access wilderness areas, and should not require more than one or two people to operate the system. The techno-economic analysis assesses fixed and variable costs. It suggests that the economy of scale is an important factor, as higher throughput directly leads to improved system economic viability. Labor and capital equipment are the driving factors in the viability of the system. The break

  11. Dissolved Organic Carbon Cycling and Transformation Dynamics in A Northern Forested Peatland

    Science.gov (United States)

    Tfaily, M. M.; Lin, X.; Chanton, P. R.; Steinweg, J.; Esson, K.; Kostka, J. E.; Cooper, W. T.; Schadt, C. W.; Hanson, P. J.; Chanton, J.

    2013-12-01

    Peatlands sequester one-third of all soil carbon and currently act as major sinks of atmospheric carbon dioxide. The ability to predict or simulate the fate of stored carbon in response to climatic disruption remains hampered by our limited understanding of the controls of carbon turnover and the composition and functioning of peatland microbial communities. A combination of advanced analytical chemistry and microbiology approaches revealed that organic matter reactivity and microbial community dynamics were closely coupled in an extensive field dataset compiled at the S1 bog site established for the SPRUCE program, Marcell Experimental Forest (MEF). The molecular composition and decomposition pathways of dissolved organic carbon (DOC) were contrasted using parallel factor (PARAFAC)-modeled excitation emission fluorescence spectroscopy (EEMS) and FT-ICR MS. The specific UV absorbance (SUVA) at 254 nm was calculated as an indicator of aromaticity. Fluorescence intensity ratios (BIX and FI) were used to infer the relative contributions from solid phase decomposition and microbial production. Distributions of bulk DOC, its stable (δ13C) and radioactive (Δ14C) isotopic composition were also utilized to infer information on its dynamics and transformation processes. Strong vertical stratification was observed in organic matter composition, the distribution of mineralization products (CO2, CH4), respiration rates, and decomposition pathways, whereas smaller variations were observed between sites. A decline in the aromaticity of pore water DOC was accompanied by an increase in microbially-produced DOC. Solid phase peat, on the other hand, became more humified and highly aromatic with depth. These observations were consistent with radiocarbon data that showed that the radiocarbon signatures of microbial respiration products in peat porewaters more closely resemble those of DOC rather than solid peat, indicating that carbon from recent photosynthesis is fueling the

  12. Response of sugar maple to calcium addition to northern hardwood forest.

    Science.gov (United States)

    Juice, Stephanie M; Fahey, Timothy J; Siccama, Thomas G; Driscoll, Charles T; Denny, Ellen G; Eagar, Christopher; Cleavitt, Natalie L; Minocha, Rakesh; Richardson, Andrew D

    2006-05-01

    Watershed budget studies at the Hubbard Brook Experimental Forest (HBEF), New Hampshire, USA, have demonstrated high calcium depletion of soil during the 20th century due, in part, to acid deposition. Over the past 25 years, tree growth (especially for sugar maple) has declined on the experimental watersheds at the HBEF. In October 1999, 0.85 Mg Ca/ha was added to Watershed 1 (W1) at the HBEF in the form of wollastonite (CaSiO3), a treatment that, by summer 2002, had raised the pH in the Oie horizon from 3.8 to 5.0 and, in the Oa horizon, from 3.9 to 4.2. We measured the response of sugar maple to the calcium fertilization treatment on W1. Foliar calcium concentration of canopy sugar maples in W1 increased markedly beginning the second year after treatment, and foliar manganese declined in years four and five. By 2005, the crown condition of sugar maple was much healthier in the treated watershed as compared with the untreated reference watershed (W6). Following high seed production in 2000 and 2002, the density of sugar maple seedlings increased significantly on W1 in comparison with W6 in 2001 and 2003. Survivorship of the 2003 cohort through July 2005 was much higher on W1 (36.6%) than W6 (10.2%). In 2003, sugar maple germinants on W1 were approximately 50% larger than those in reference plots, and foliar chlorophyll concentrations were significantly greater (0.27 g/m2 vs. 0.23 g/m2 leaf area). Foliage and fine-root calcium concentrations were roughly twice as high, and manganese concentrations twice as low in the treated than the reference seedlings in 2003 and 2004. Mycorrhizal colonization of seedlings was also much greater in the treated (22.4% of root length) than the reference sites (4.4%). A similar, though less dramatic, difference was observed for mycorrhizal colonization of mature sugar maples (56% vs. 35%). These results reinforce and extend other regional observations that sugar maple decline in the northeastern United States and southern Canada is

  13. Temperature & wood source control PyOM turnover in a Northern American forest

    Science.gov (United States)

    Hatton, Pierre-Joseph; Le Moine, James; Auclerc, Apolline; Gormley, Mark; Filley, Tim R.; Nadelhoffer, Knute J.; Bird, Jeff. A.

    2016-04-01

    Surprisingly little is known about how pyrolysis temperature and wood source affect the stability of forest-fire derived pyrogenic organic matter (PyOM). Here, we show that wood source and temperature affect in situ mineralization rates of PyOM in soils for two co-occurring gymnosperm (jack pine; JP [Pinus banksiana]) and angiosperm (red maple; RM [Acer rubrum])¬ species from North American boreal-temperate ecotones. We assess the effect of pyrolysis temperature on PyOM fates by following the decay of 13C/15N-enriched JP wood (JPwood) and PyOM produced at 300 °C (JP300) and 450 °C (JP450); and assess the effect of PyOM wood source by comparing fates of JP450 and RM450. JPwood mineralized 18× faster than JP300 and 44× faster than JP450 after 2.8y. RM450 mineralized initially faster than JP450 during the first ~2y, but became equivalent afterwards (1.1±0.2% of CO¬2 losses after 2.8y). Modeled turnover times suggest that this can be attributed to ~1% of fast-cycling PyOM (wood source (yet); N recoveries did not differ. PLFA-(13)C data reveal that (i) treatments have similar microbial communities after 1y, (ii) JPwood is preferentially utilized by fungi, and (iii) bacteria increasingly utilize PyOM as pyrolysis temperature increases. Estimated carbon use efficiency decreased with increasing pyrolysis temperature (JPwood~JP300>JP450~RM450). Although insignificant, potential phenol oxidase and peroxidase activities decrease with increasing pyrolysis temperature. Neither PyOM nor wood additions (~11% of soil C stock 0-20 cm depth) affected pH or Ec after 1y. We provide the first, field experimental evidence that pyrolysis temperature and wood source affect the turnover of PyOM in soil. We show faster, initial decay for PyOM produced at lesser temperature and RM (angiosperm) compared with JP (gymnosperm). This study offers realistic insights on (i) the controls underlying in situ PyOM turnover, and on (ii) how ongoing/projected changes in tree species composition

  14. Effects of structural complexity enhancement on eastern red-backed salamander (Plethodon cinereus) populations in northern hardwood forests

    Science.gov (United States)

    McKenny, H.C.; Keeton, W.S.; Donovan, T.M.

    2006-01-01

    Managing for stand structural complexity in northern hardwood forests has been proposed as a method for promoting microhabitat characteristics important to eastern red-backed salamanders (Plethodon cinereus). We evaluated the effects of alternate, structure-based silvicultural systems on red-backed salamander populations at two research sites in northwestern Vermont. Treatments included two uneven-aged approaches (single-tree selection and group-selection) and one unconventional approach, termed "structural complexity enhancement" (SCE), that promotes development of late-successional structure, including elevated levels of coarse woody debris (CWD). Treatments were applied to 2 ha units and were replicated two to four times depending on treatment. We surveyed red-backed salamanders with a natural cover search method of transects nested within vegetation plots 1 year after logging. Abundance estimates corrected for detection probability were calculated from survey data with a binomial mixture model. Abundance estimates differed between study areas and were influenced by forest structural characteristics. Model selection was conducted using Akaike Information Criteria, corrected for over-dispersed data and small sample size (QAICc). We found no difference in abundance as a response to treatment as a whole, suggesting that all of the uneven-aged silvicultural systems evaluated can maintain salamander populations after harvest. However, abundance was tied to specific structural habitat attributes associated with study plots within treatments. The most parsimonious model of habitat covariates included site, relative density of overstory trees, and density of more-decayed and less-decayed downed CWD. Abundance responded positively to the density of downed, well-decayed CWD and negatively to the density of poorly decayed CWD and to overstory relative density. CWD volume was not a strong predictor of salamander abundance. We conclude that structural complexity enhancement

  15. Climatic sensitivity, water-use efficiency, and growth decline in boreal jack pine (Pinus banksiana) forests in Northern Ontario

    Science.gov (United States)

    Dietrich, Rachel; Bell, F. Wayne; Silva, Lucas C. R.; Cecile, Alice; Horwath, William R.; Anand, Madhur

    2016-10-01

    Rises in atmospheric carbon dioxide (atmCO2) levels are known to stimulate photosynthesis and increase intrinsic water-use efficiency (iWUE) in trees. Stand-level increases in iWUE depend on the physiological response of dominant species to increases in atmCO2, while tree-level response to increasing atmCO2 depends on the balance between the direct effects of atmCO2 on photosynthetic rate and the indirect effects of atmCO2 on drought conditions. The aim of this study was to characterize the response of boreal jack pine (Pinus banksiana) stands in Northern Ontario to changes in atmCO2 and associated climatic change over the past 100 years. The impact of changes in growing season length, temperature, and precipitation, as well as atmCO2 on tree growth, was determined using stable carbon isotopes and dendrochronological analysis. Jack pine stands in this study were shown to be in progressive decline. As expected, iWUE was found to increase in association with rising atmCO2. However, increases in iWUE were not directly coupled with atmCO2, suggesting that the degree of iWUE improvement is limited by alternative factors. Water-use efficiency was negatively associated with tree growth, suggesting that warming- and drought-induced stomatal closure has likely led to deviations from expected atmCO2-enhanced growth. This finding corroborates that boreal forest stands are likely to face continued stress under future climatic warming.

  16. Upland log volumes and conifer establishment patterns in two northern, upland old-growth redwood forests, a brief synopsis

    Science.gov (United States)

    Daniel J. Porter; John O. Sawyer

    2007-01-01

    We characterized the volume, weight and top surface area of naturally fallen logs in an old-growth redwood forest, and quantified conifer recruit densities on these logs and on the surrounding forest floor. We report significantly greater conifer recruit densities on log substrates as compared to the forest floor. Log substrate availability was calculated on a per...

  17. Carbon content of forest floor and mineral soil in Mediterranean Pinus spp. and Oak stands in acid soils in Northern Spain

    Energy Technology Data Exchange (ETDEWEB)

    Herrero, C.; Turrión, M.B.; Pando, V.; Bravo, F.

    2016-07-01

    Aim of the study: The aim of the study was to determine the baseline carbon stock in forest floor and mineral soils in pine and oak stands in acid soils in Northern Spain. Area of study: The study area is situated in northern Spain (42° N, 4° W) on “Paramos y Valles” region of Palencia. aterial and methods: An extensive monitoring composed of 48 plots (31 in pine and 17 in oak stands) was carried out. Litter layers and mineral soil samples, at depths of 0-30 cm and 30-60 cm, were taken in each plot. An intensive monitoring was also performed by sampling 12 of these 48 plots selected taken in account species forest composition and their stand development stage. Microbial biomass C (CMB), C mineralization (CRB), and soil organic C balance at stand level were determined in surface soil samples of intensive monitoring. Main results: No differences in soil C content were detected in the two forest ecosystems up to 60 cm depth (53.0±25.8 Mg C ha-1 in Pinus spp. plantations and 60.3±43.8 Mg C ha-1 in oak stands). However, differences in total C (CT), CMB and CRB were found in the upper 10 cm of the soils depending on the stand development stage in each species forest composition (Pinus nigra, Pinus pinaster, Pinus sylvestris and Quercus pyrenaica). Plots with high development stage exhibited significant lower metabolic quotient (qCO2), so, meant more efficient utilization of C by the microbial community. The C content in the forest floor was higher in pine stands (13.7±0.9 Mg C ha-1) than in oak stands (5.4±0.7 Mg C ha-1). A greater turnover time was found in pine ecosystems vs. oak stands. In contrast, forest floor H layer was nonexistent in oak stands. Research highlights: Results about litterfall, forest floor and mineral soil dynamics in this paper can be used strategically to reach environmental goals in new afforestation programs and sustainable forest management approaches. (Author)

  18. Arizona Geophysical Data Base

    OpenAIRE

    McLeod, Ronald G.

    1981-01-01

    A series of digital data sets were compiled for input into a geophysical data base for a one degree quadrangle in Arizona. Using a Landsat digital mosaic as a base, information on topography, geology, gravity as well as Seasat radar imagery were registered. Example overlays and tabulations are performed.

  19. Arizona's School Asbestos Program.

    Science.gov (United States)

    Charette, Mike L.

    1982-01-01

    The state of Arizona Department of Education operates a successful program to remove asbestos-containing building materials from schools, drawing from the expertise of the Department of Health Services, Bureau of Environmental Hygiene and Sanitation, Bureau of Waste Control, and eliciting cooperation of school officials. Includes an asbestos…

  20. Arizona Academic Standards: Kindergarten

    Science.gov (United States)

    Arizona Department of Education, 2009

    2009-01-01

    This publication contains Arizona public schools' academic standards for kindergarten. The contents of this document include the following: (1) The Arts Standard 2006--Kindergarten; (2) Comprehensive Health Education/Physical Activity Standards 1997--Readiness (Kindergarten); (3) Foreign and Native Language Standards 1997--Readiness…

  1. 苏北山丘区森林群落枯枝落叶层的生态功能分析%Analysis on Ecological Function of Forest Floor of Forest Community in the Hilly Region of Northern Jiangsu Province

    Institute of Scientific and Technical Information of China (English)

    杨盼盼; 于法展; 曾晨; 周颖

    2011-01-01

    A study was carried out on ecological functions of forest floor,such as standing stock of litter,detainment of heavy metals,nutrient storage ability and water holding capacity of six typical forest communities in the hilly region of northern Jiangsu Province.The results show that with regard to standing stock of litter,for N storage capacity and the water holding capacity of forest floor,the Quercus community is the highest among the six forest communities,while as far as P and five heavy metals storage capacity is concerned,the Platycladus orientails forest community is the highest and followed by the Quercus.By comparison,the Pinus densiflora and Pinus thunbergli forest and Robinia pseudoacacia forest community are inferior in all these aspects.%通过对苏北山丘区6种代表性森林群落枯落物现存量、吸纳重金属、养分贮存能力和蓄水固土等生态功能的研究,结果表明:6种代表性森林群落枯枝落叶层现存量、对氮的贮存能力以及最大拦蓄量均以栎类林群落最大;对磷和5种重金属的贮存量以侧柏林群落最大,栎类林群落次之;赤松林、黑松林和刺槐林群落的各项生态功能相对较弱。

  2. The influence of changes in soil moisture in association with geomorphic change on the formation of a subalpine coniferous forest on Mt. Akita-Komagatake, northern Japan

    Science.gov (United States)

    Konno, A.

    2015-12-01

    The coniferous forest (largely composed of Abies mariesii) is presently the typical vegetation of the subalpine zone in Japan. Pollen analysis revealed that few A. mariesii were present during the last glacial period, and the species began to expand to the subalpine zone during the Holocene (Morita, 1992). However, on Mt. Akita-Komagatake in northern Japan, the expected predominance of A. mariesii is not extensively observed, and the predominant vegetation is instead the dwarf bamboo (Sasa kurilensis). It is unknown why the area under coniferous forest is small in this region. Therefore, I examined this issue from the perspectives of (1) distribution of vegetation, (2) geomorphology, (3) soil moisture, and (4) vegetation history. (1) Precise digital elevation model data and photographic interpretation showed that this coniferous forest was densely distributed in a flat segment considered to be formed by a landslide; (2) this landslide is thought to have occurred up to 3,699 ± 26 yr BP because a boring-core specimen from the landslide included the AK-3 tephra layer (2,300-2,800 yr BP: Wachi et al, 1997) and the radiocarbon date of the lowermost humic soil layer was 3,699 ± 26 yr BP; (3) the soil in the forest area had higher volumetric water content than that in the non-forest area; and (4) phytolith analysis revealed that the main species in the study site was initially dwarf bamboo, but coniferous forest replaced it after the Towada-a tephra (1035 cal. BP, Machida and Arai, 1992) layer fell. These results suggest that soil water conditions changed because of the formation of the flat segment by the landslide, and the coniferous forest was consequently established. However, the landslide only indirectly affected the formation of the coniferous forest, because the forest developed over several thousand years after the landslide occurred. In other words, more direct reasons for the establishment of the coniferous forest may involve changes in soil moisture. This

  3. The role of non-timber forest products to communities living in the Northern periphery of the Korup National Park

    Directory of Open Access Journals (Sweden)

    Afungang Ngwatung

    2013-12-01

    Full Text Available Non-timber forest products (NTFPs extraction and trade is considered an income generating activity for subsistence livelihood in rural forest communities in Cameroon. This paper is to ascertain whether Non-timber forest products exploitation and commercialization is economically profitable to livelihood or just a customary activity promoted by economic hardship. Surveys involving 184 households, parcel inventories, interviews and reviews were used revealing that Non-timber forest products exploitation and farming occupy 90.8% and 80.4% respectively of the total work force. Agricultural contribute 66% against 31% for Non-timber forest products to the local economy. Policy changes like the institutionalization of community forest and decentralizations in 1997 and the transfer of authoritative regulation to peripheral actors in the mid-1990s permitted local benefit from Non-timber forest products resources.

  4. Fertilization of Northern Hardwoods

    Science.gov (United States)

    R. Lea; D.G. Brockway

    1986-01-01

    Northern hardwoods grow over a considerable range of climatic and edaphic conditions and exhibit a wide range in productivity.Many northern hardwood forests are capable of high production relative to other forest types, but are often slow to reach maximum productivity because of low nutrient availability.Altering the patterns of biomass accumulation so that managers...

  5. The Virtual Arizona Experience

    Science.gov (United States)

    Allison, M. L.; Davis, R.; Conway, F. M.; Bellasai, R.

    2012-12-01

    To commemorate the once-in-a-lifetime event of Arizona's hundredth birthday, the Centennial Commission and the Governor of Arizona envisioned a museum and companion website that would capture the state's history, celebrate its people, and embrace its future. Working with world-renowned museum designers, the state began to seek ideas from across Arizona to create plans for a journey of discovery through science and the humanities. The museum would introduce visitors to some of the people who nurtured the state through its early years and others who are innovating its tomorrows. Showcases would include the resources and experiences that shaped the state's history and are transforming its present day, highlighting the ingenuity that tamed the wild frontier and is envisioning Arizona's next frontiers through science and technology. The Arizona Experience (www.arizonaexperience.org) was initially intended to serve as the web presence for the physical museum, but as delays occurred with the physical museum, the site has quickly developed an identify of its own as an interactive, multimedia experience, reaching a wider audience with functions that would be difficult or expensive to produce in a museum. As leaders in scientific and technological innovation in the state, the Arizona Geological Survey was tasked with designing and creating the Arizona Experience site. The general themes remain the same; however, the site has added content and applications that are better suited to the online environment in order to create a rich, dynamic supplement to a physical museum experience. The website offers the features and displays of the future museum with the interactive nature and learning environment of the web. This provides an encyclopedic overview of the State of Arizona by subject matter experts in a manner that is free and open to the public and erases socio-economic, political, and physical boundaries. Over the Centennial Year of 2012 the site will release a new theme and

  6. Secondary formation of oxalic acid and related organic species from biogenic sources in a larch forest at the northern slope of Mt. Fuji

    Science.gov (United States)

    Mochizuki, Tomoki; Kawamura, Kimitaka; Miyazaki, Yuzo; Wada, Ryuichi; Takahashi, Yoshiyuki; Saigusa, Nobuko; Tani, Akira

    2017-10-01

    To better understand the formation of water-soluble organic aerosols in the forest atmosphere, we measured low molecular weight (LMW) dicarboxylic acids, oxocarboxylic acids, α-dicarbonyls, unsaturated fatty acids (UFAs), and water-soluble organic carbon (WSOC) in aerosols from a Larix kaempferi forest located at the northern slope of Mt. Fuji, Japan, in summer 2012. Concentrations of dicarboxylic acids, oxocarboxylic acids, α-dicarbonyls, and WSOC showed maxima in daytime. Relative abundance of oxalic acid in LMW dicarboxylic acids was on average 52% and its average concentration was 214 ng m-3. We found that diurnal and temporal variations of oxalic acid are different from those of isoprene and α-pinene, whereas biogenic secondary organic aerosols (BSOAs) derived from isoprene and α-pinene showed similar variations with oxalic acid. The mass concentration ratios of oxalic acid/BSOAs were relatively constant, although a large variation in the concentrations of toluene that is an anthropogenic volatile organic compound was observed. These results suggest that formation of oxalic acid is associated with the oxidation of isoprene and α-pinene with O3 and other oxidants in the forest atmosphere. In addition, concentrations of UFAs were observed, for the first time, to decrease dramatically during daytime in the forest. Mass concentration ratios of azelaic acid to UFAs showed a positive correlation with O3, suggesting that UFAs are oxidized to yield azelaic acid, which may be further decomposed to oxalic acid in the forest atmosphere. We found that contributions of oxalic acid to WSOC are significantly high ranging from 3.7 to 9.7% (average 6.0%). This study demonstrates that forest ecosystem is an important source of oxalic acid and other dicarboxylic acids in the atmosphere.

  7. Different characteristics of new particle formation between urban and deciduous forest sites in Northern Japan during the summers of 2010-2011

    Science.gov (United States)

    Jung, J.; Miyazaki, Y.; Kawamura, K.

    2013-01-01

    To investigate new particle formation (NPF) events in urban and forest environments, number size distributions of ultrafine particles were measured at an urban site and a deciduous forest site in Sapporo, Northern Japan, during the summers of 2011 and 2010, respectively. The burst of nucleation mode particles at the urban site typically started in the morning (07:00-11:30 local time, LT) with simultaneous increases in SO2 and O3 concentrations and the UV index under clear (sunny) weather conditions. The growth rates of nucleated particles at the urban site ranged from 5.0 to 7.8 nm h-1 with an average of 6.3 ± 1.1 nm h-1. NPF events at the urban site were separated into events with or without subsequent particle growth after the burst of nucleation mode particles. This division was found to relate to prevailing wind direction because the subsequent growth of freshly nucleated particles typically occurred when wind direction shifted to northwesterly (from residential and public park areas), whereas it did not occur under southeasterly winds (from the downtown area). During the periods with NPF events, elevated concentrations of non-methane hydrocarbons (NMHC) were obtained under conditions of northwesterly winds when compared to southeasterly winds, whereas no difference in SO2 levels was recorded. These results suggest that variations in NMHC concentration may play an important role in the growth of freshly nucleated particles at the urban site. The burst of nucleation mode particles at the forest site typically started around noon (10:30-14:30 LT), which was 3-4 h later than that at the urban site. Interestingly, at the forest site the burst of nucleation mode particles usually started when air masses originating from urban Sapporo arrived at the forest site. The present study indicates that the inflow of these urban air masses acted as a trigger for the initiation of the burst of nucleation mode particles in the deciduous forest.

  8. New species of high elevation cloud forest butterflies of the genus Pedaliodes Butler from the northern Colombian Andes (Lepidoptera, Nymphalidae, Satyrinae).

    Science.gov (United States)

    Pyrcz, Tomasz W; Prieto, Carlos; Viloria, Angel L; Andrade, Gonzalo

    2013-01-01

    Four new species of Pedaliodes Butler (i.e., P. adrianae, n. sp., P. haydoni, n. sp., P. philinae, n. sp. and P. rodriguezi, n. sp.) are described from the high elevation cloud forests in the Frontino massif in the Colombian Western Cordillera and the northern part of the Central and Eastern Cordilleras. The affinities of these new species with other congeners are discussed. The total number of described species of Colombian Pronophilina is increased to 208, with a particularly high total number of species (88) and proportion of endemic species (26%) in the Western Cordillera.

  9. Daily Activities of the Giant Pill-Millipede Zephronia cf. viridescens Attems, 1936 (Diplopoda: Sphaerotheriida: Zephroniidae) in a Deciduous Forest in Northern Thailand

    DEFF Research Database (Denmark)

    Wongthamwanich, N.; Panha, S.; Sitthicharoenchai, D.;

    2013-01-01

    Daily activities of the giant pill-millipede Zephronia cf. viridescens Attems, 1936 (Diplopoda: Sphaerotheriida: Zephroniidae) in a deciduous forest in northern Thailand. Zoological Studies 51(7): 913-926. For the 1st time in the order Sphaerotheriida, daily activities of the giant pill-millipede....... It was concluded that females tend to accumulate energy throughout the day, probably for reproduction, while males tend to spend more time walking, probably for the purpose of finding mates. http://zoolstud.sinica.edu.tw/Journals/51.7/913.pdf...

  10. Forests, Water, and the Atmosphere in Northern California: Insights from Sap-Flow Data Analysis and Numerical Atmospheric Model Simulations

    Science.gov (United States)

    Link, Percy Anne

    Evapotranspiration cools the land surface by consuming a large fraction of the net radiative energy at the surface. In forested regions, trees actively control the rate of transpiration by modulating stomatal conductance in response to environmental conditions, and species with different stomatal dynamics can affect the atmosphere in distinct ways. Using principal component analysis (PCA) and Markov chain Monte Carlo (MCMC) parameter estimation with direct, tree-level measurements of water use, we show that Douglas-firs ( Pseudotsuga menziesii), a common evergreen needleleaf tree species in the Northern California Coast Range, decrease their transpiration sharply in the summer dry season in response to a dry root zone; and in contrast, broadleaf evergreen tree species, especially Pacific madrones (Arbutus menziesii), transpire maximally in the summer dry season because their transpiration is much less sensitive to a dry root zone and increases continually in response to increasing atmospheric evaporative demand. We scale up these tree-level observations to construct a bottom-up estimate of regional transpiration, and we use these regional estimates along with atmospheric models, one simple and one comprehensive, to quantify the potential impact of species transpiration differences on regional summertime climate. The atmospheric models suggest that these species differences in transpiration could affect the well-mixed atmospheric boundary layer temperature and humidity by 1-1.5 degrees C and 1 g/kg, respectively, and near-surface temperature and humidity by 1.5-2.5 degrees C and 2-3 g/kg, respectively. We further investigate the sensitivity of California climate to evapotranspiration by estimating the sensitivity of wind energy forecasts at a California wind farm to regional-scale perturbations in soil moisture using a regional atmospheric model. These tests show that forecasts at this particular farm are most sensitive to soil moisture in the Central Valley, and

  11. Geophysical lineaments of Arizona

    Energy Technology Data Exchange (ETDEWEB)

    Lepley, L.K.

    1979-08-01

    Photolineaments seen on satellite images are usually expressions of deep crustal ruptures. However, photolineaments are omnipresent and an independent expression of regional discontinuities is needed to help rank the photolineaments. Published gravity and magnetic contour maps of Arizona were analyzed to produce a single geophysical lineament map to indicate trends of regional basement structures. This map shows that the southwestern quarter of Arizona is dominated by a NNW-ENE orthogonal system whereas the remainder of the state is gridded by a NW-NE system. North-south systems are present throughout the state, as are EW lineaments. Arizona is transected by the WNW Texas Strand, but other shorter systems trending in the Texas direction are found throughout the state south of the Strand. The major lineament systems as seen on Landsat, gravity, and magnetic maps correlate reasonably well with known geothermal manifestations. Many other systems are Precambrian, Paleozoic, and/or Mesozoic in age but appear to control the location of Quaternary volcanic systems.

  12. Moving the boundaries of forest and land use history - the case of Upper East Region in northern Ghana

    DEFF Research Database (Denmark)

    Wardell, David Andrew

    2005-01-01

    Africa; Northern Territories of the Gold Coast Colony; colonial history; environmental history; land cover and land use change; migration and the opportunity structure......Africa; Northern Territories of the Gold Coast Colony; colonial history; environmental history; land cover and land use change; migration and the opportunity structure...

  13. Nitrogen addition affects leaf nutrition and photosynthesis in sugar maple in a nutrient-poor northern Vermont forest

    Science.gov (United States)

    David S. Ellsworth

    1999-01-01

    Sugar maple-dominated forest ecosystems in the northeastern U.S. have been receiving precipitation nitrogen (N) inputs of 15 -20 kg N ha1 year1 since at least the mid 1980s sustained chronic N inputs of this magnitude into nutrient-poor forest ecosystems may cause eutrophication and affect ecosystem functioning as well as...

  14. Predicting the retreat and migration of tidal forests along the northern Gulf of Mexico under sea-level rise

    Science.gov (United States)

    Doyle, T.W.; Krauss, K.W.; Conner, W.H.; From, A.S.

    2010-01-01

    Tidal freshwater forests in coastal regions of the southeastern United States are undergoing dieback and retreat from increasing tidal inundation and saltwater intrusion attributed to climate variability and sea-level rise. In many areas, tidal saltwater forests (mangroves) contrastingly are expanding landward in subtropical coastal reaches succeeding freshwater marsh and forest zones. Hydrological characteristics of these low-relief coastal forests in intertidal settings are dictated by the influence of tidal and freshwater forcing. In this paper, we describe the application of the Sea Level Over Proportional Elevation (SLOPE) model to predict coastal forest retreat and migration from projected sea-level rise based on a proxy relationship of saltmarsh/mangrove area and tidal range. The SLOPE model assumes that the sum area of saltmarsh/mangrove habitat along any given coastal reach is determined by the slope of the landform and vertical tide forcing. Model results indicated that saltmarsh and mangrove migration from sea-level rise will vary by county and watershed but greater in western Gulf States than in the eastern Gulf States where millions of hectares of coastal forest will be displaced over the next century with a near meter rise in relative sea level alone. Substantial losses of coastal forests will also occur in the eastern Gulf but mangrove forests in subtropical zones of Florida are expected to replace retreating freshwater forest and affect regional biodiversity. Accelerated global eustacy from climate change will compound the degree of predicted retreat and migration of coastal forests with expected implications for ecosystem management of State and Federal lands in the absence of adaptive coastal management.

  15. Kaljujooniste keskus Arizonas / Andres Kurg

    Index Scriptorium Estoniae

    Kurg, Andres, 1975-

    1998-01-01

    Arhitekt William Bruderi projekteeritud kaljujooniste uurimis- ja eksponeerimiskeskus Phoenixis, Arizonas säilitab kivijooniseid, mille autoriteks olid sealset piirkonda kuni 16. sajandini asustanud hohokamid

  16. Kaljujooniste keskus Arizonas / Andres Kurg

    Index Scriptorium Estoniae

    Kurg, Andres, 1975-

    1998-01-01

    Arhitekt William Bruderi projekteeritud kaljujooniste uurimis- ja eksponeerimiskeskus Phoenixis, Arizonas säilitab kivijooniseid, mille autoriteks olid sealset piirkonda kuni 16. sajandini asustanud hohokamid

  17. Impact of payments for environmental services and protected areas on local livelihoods and forest conservation in northern Cambodia

    Science.gov (United States)

    Clements, Tom; Milner-Gulland, E J

    2015-01-01

    The potential impacts of payments for environmental services (PES) and protected areas (PAs) on environmental outcomes and local livelihoods in developing countries are contentious and have been widely debated. The available evidence is sparse, with few rigorous evaluations of the environmental and social impacts of PAs and particularly of PES. We measured the impacts on forests and human well-being of three different PES programs instituted within two PAs in northern Cambodia, using a panel of intervention villages and matched controls. Both PES and PAs delivered additional environmental outcomes relative to the counterfactual: reducing deforestation rates significantly relative to controls. PAs increased security of access to land and forest resources for local households, benefiting forest resource users but restricting households’ ability to expand and diversify their agriculture. The impacts of PES on household well-being were related to the magnitude of the payments provided. The two higher paying market-linked PES programs had significant positive impacts, whereas a lower paying program that targeted biodiversity protection had no detectable effect on livelihoods, despite its positive environmental outcomes. Households that signed up for the higher paying PES programs, however, typically needed more capital assets; hence, they were less poor and more food secure than other villagers. Therefore, whereas the impacts of PAs on household well-being were limited overall and varied between livelihood strategies, the PES programs had significant positive impacts on livelihoods for those that could afford to participate. Our results are consistent with theories that PES, when designed appropriately, can be a powerful new tool for delivering conservation goals whilst benefiting local people. El Impacto de los Pagos por Servicios Ambientales y Áreas Protegidas sobre la Subsistencia Local y la Conservación del Bosque en el Norte de Camboya Resumen Los impactos

  18. Libraries in Arizona: MedlinePlus

    Science.gov (United States)

    ... Library → Libraries in Arizona URL of this page: https://medlineplus.gov/libraries/arizona.html Libraries in Arizona ... Candy Lane Cottonwood, AZ 86326 928-639-6444 http://nahealth.com Flagstaff Flagstaff Medical Center John B. ...

  19. Tools for forming strategies for remediation of forests and park areas in northern Europe after radioactive contamination: background and techniques

    Energy Technology Data Exchange (ETDEWEB)

    Hubbard, L. [Swedish Radiation Protection Authority, SSI (Sweden); Rantavaara, A. [Radiation and Nuclear Safety Autority, STUK (Finland); Andersson, K. [Risoe National Lab., Roskilde (Denmark); Roed, J. [Risoe National Lab., Roskilde (Denmark)

    2002-01-01

    This report compiles background information that can be used in planning appropriate countermeasures for forest and park areas in Denmark, Sweden, Finland and Norway, in case a nuclear accident results in large-scale contamination of forests. The information is formulated to inform the forestry sector and radiation protection experts about the practicality of both forest management techniques and mechanical cleanup methods, for use in their planning of specific strategies that can lead to an optimal use of contaminated forests. Decisions will depend on the site and the actual situation after radioactive deposition to forested areas, but the report provides background information from investigations performed before an accident occurs that will make the process more effective. The report also discusses the radiological consequences of producing energy from biomass contaminated by a major nuclear accident, both in the context of normal bio-fuel energy production and as a means of reducing potentially severe environmental problems in the forest by firing power plants with highly contaminated forest biomass. (au)

  20. Long-Term Record of Sampled Disturbances in Northern Eurasian Boreal Forest from Pre-2000 Landsat Data

    Directory of Open Access Journals (Sweden)

    Dong Chen

    2014-06-01

    Full Text Available Stand age distribution is an important descriptor of boreal forest structure, which is directly linked to many ecosystem processes including the carbon cycle, the land–atmosphere interaction and ecosystem services, among others. Almost half of the global boreal biome is located in Russia. The vast extent, remote location, and limited accessibility of Russian boreal forests make remote sensing the only feasible approach to characterize these forests to their full extent. A wide variety of satellite observations are currently available to monitor forest change and infer its structure; however, the period of observations is mostly limited to the 2000s era. Reconstruction of wall-to-wall maps of stand age distribution requires merging longer-term site observations of forest cover change available at the Landsat scale at a subset of locations in Russia with the wall-to-wall coverage available from coarse resolution satellites since 2000. This paper presents a dataset consisting of a suite of multi-year forest disturbance samples and samples of undisturbed forests across Russia derived from Landsat Thematic Mapper and Enhanced Thematic Mapper Plus images from 1985 to 2000. These samples provide crucial information regarding disturbance history in selected regions across the Russian boreal forest and are designed to serve as a training and/or validation dataset for coarse resolution data products. The overall accuracy and Kappa coefficient for the entire sample collection was found to be 83.98% and 0.83%, respectively. It is hoped that the presented dataset will benefit subsequent studies on a variety of aspects of the Russian boreal forest, especially in relation to the carbon budget and climate.

  1. Arizona Measure of Academic Progress: Growth in Arizona Schools.

    Science.gov (United States)

    Garcia, David; Aportela, Anabel

    This document contains reports of school district results on the Arizona Measure of Academic Progress by school and grade level for the 1999-2000 school year. Lengthy tables present results for reading and mathematics showing the change in achievement between grades each year from grades 2 to 3 to grades 7 to 8. The Arizona Measure of Academic…

  2. Distribution of dead wood volume and mass in mediterranean Fagus sylvatica L. forests in Northern Iberian Peninsula. Implications for field sampling inventory

    Directory of Open Access Journals (Sweden)

    Celia Herrero

    2016-12-01

    Full Text Available Aim of study: The aim of this study was to 1 estimate the amount of dead wood in managed beech (Fagus sylvatica L. stands in northern Iberian Peninsula and 2 evaluate the most appropriate volume equation and the optimal transect length for sampling downed wood. Area of study: The study area is the Aralar Forest in Navarra (Northern Iberian Peninsula. Material and methods: The amount of dead wood by component (downed logs, snags, stumps and fine woody debris was inventoried in 51 plots across a chronosequence of stand ages (0-120 years old. Main results: The average volume and biomass of dead wood was 24.43 m3 ha-1 and 7.65 Mg ha-1, respectively. This amount changed with stand development stage [17.14 m3 ha-1 in seedling stage; 34.09 m3 ha-1 inpole stage; 22.54 m3 ha-1 in mature stage and 24.27 m3 ha-1 in regular stand in regeneration stage], although the differences were not statistically significant for coarse woody debris. However, forest management influenced the amount of dead wood, because the proportion of mass in the different components and the decay stage depended on time since last thinning. The formula based on intersection diameter resulted on the smallest coefficient of variation out of seven log-volume formulae. Thus, the intersection diameter is the preferred method because it gives unbiased estimates, has the greatest precision and is the easiest to implement in the field. Research highlights: The amount of dead wood, and in particular snags, was significantly lower than that in reserved forests. Results of this study showed that sampling effort should be directed towards increasing the number of transects, instead of increasing transect length or collecting additional piece diameters that do not increase the accuracy or precision of DWM volume estimation. Keywords: snags; downed logs; stumps; fine woody debris; beech; line intersect sampling.

  3. Monitoring and assessment of soil erosion at micro-scale and macro-scale in forests affected by fire damage in northern Iran.

    Science.gov (United States)

    Akbarzadeh, Ali; Ghorbani-Dashtaki, Shoja; Naderi-Khorasgani, Mehdi; Kerry, Ruth; Taghizadeh-Mehrjardi, Ruhollah

    2016-12-01

    Understanding the occurrence of erosion processes at large scales is very difficult without studying them at small scales. In this study, soil erosion parameters were investigated at micro-scale and macro-scale in forests in northern Iran. Surface erosion and some vegetation attributes were measured at the watershed scale in 30 parcels of land which were separated into 15 fire-affected (burned) forests and 15 original (unburned) forests adjacent to the burned sites. The soil erodibility factor and splash erosion were also determined at the micro-plot scale within each burned and unburned site. Furthermore, soil sampling and infiltration studies were carried out at 80 other sites, as well as the 30 burned and unburned sites, (a total of 110 points) to create a map of the soil erodibility factor at the regional scale. Maps of topography, rainfall, and cover-management were also determined for the study area. The maps of erosion risk and erosion risk potential were finally prepared for the study area using the Revised Universal Soil Loss Equation (RUSLE) procedure. Results indicated that destruction of the protective cover of forested areas by fire had significant effects on splash erosion and the soil erodibility factor at the micro-plot scale and also on surface erosion, erosion risk, and erosion risk potential at the watershed scale. Moreover, the results showed that correlation coefficients between different variables at the micro-plot and watershed scales were positive and significant. Finally, assessment and monitoring of the erosion maps at the regional scale showed that the central and western parts of the study area were more susceptible to erosion compared with the western regions due to more intense crop-management, greater soil erodibility, and more rainfall. The relationships between erosion parameters and the most important vegetation attributes were also used to provide models with equations that were specific to the study region. The results of this

  4. Effects of Chinese Fir,Loblolly Pine and Deciduous Oak Forests on Nutrient Status of Soils in Northern Subtropics of China

    Institute of Scientific and Technical Information of China (English)

    LUORU-YING; GAOZHI-QIN

    1994-01-01

    This paper deals with a study on the effects of Chinese fir,lobolly pine and deciduous oak forests o the nutrient status of soils in northern subtropics of China,adopting the principle of forest ecology in the case of similar climate and soil type.The experimental area was situated in the Xiashu Experimental Centre of Forest,where the soil is yellow-brown soil derved from siliceous slope wash.Sample plots of these 3 stands were established to study the nutrient status in litter ,the amount of nutrient uptake by roots,the quantity of nutrient output by percolating water outside the deep layer of soil,and the seasonal dynamics of available nutrient in surface soil.It was whown that the intensity of nutrient cycling in soil under deciduous oak was the highest,and the effect of oak in improving soil fertility was the best.The result of improving soil fertility by Chinese fir was the most inferior,though the intensity of nutrient cycling under that stand was higher than that under loblolly pine stand.The influence of loblolly pine on the improvement of soil fertility was better than that of Chinese fir,in spite of its lowest intensity of nutrient cycling.

  5. Inventory of forest resources (including water) by multi-level sampling. [nine northern Virginia coastal plain counties

    Science.gov (United States)

    Aldrich, R. C.; Dana, R. W.; Roberts, E. H. (Principal Investigator)

    1977-01-01

    The author has identified the following significant results. A stratified random sample using LANDSAT band 5 and 7 panchromatic prints resulted in estimates of water in counties with sampling errors less than + or - 9% (67% probability level). A forest inventory using a four band LANDSAT color composite resulted in estimates of forest area by counties that were within + or - 6.7% and + or - 3.7% respectively (67% probability level). Estimates of forest area for counties by computer assisted techniques were within + or - 21% of operational forest survey figures and for all counties the difference was only one percent. Correlations of airborne terrain reflectance measurements with LANDSAT radiance verified a linear atmospheric model with an additive (path radiance) term and multiplicative (transmittance) term. Coefficients of determination for 28 of the 32 modeling attempts, not adverseley affected by rain shower occurring between the times of LANDSAT passage and aircraft overflights, exceeded 0.83.

  6. Arizona Conserve Water Educators Guide

    Science.gov (United States)

    Project WET Foundation, 2007

    2007-01-01

    This award-winning, 350-page, full-color book provides a thorough study of Arizona water resources from a water conservation perspective. Its background section contains maps, graphs, diagrams and photos that facilitate the teaching of 15 interactive, multi-disciplinary lessons to K-12 students. In addition, 10 Arizona case studies are highlighted…

  7. Draft Programmatic Environmental Impact Statement for Revision of the Coronado National Forest Land and Resource Management Plan: Cochise, Graham, Pima, Pinal, and Santa Cruz Counties, Arizona; Hidalgo County, New Mexico

    Science.gov (United States)

    Albert Peralta; Andrea Wargo Campbell; Ann Lynch; Cheri Bowen; Christopher Stetson; Craig Wilcox; Daniela Zormeier; Debby Kriegel; Delilah Jaworski; Dustin Walters; Eli Curiel; Erin Boyle; George McKay; Janet Moser; Jennifer Morrissey; Jennifer M. Ruyle; Jeremy Sautter; Judy York; Kenna Schoenle; Larry Jones; Laura White; Linda Peery; Mary Farrell; Mindi Lehew; Mindy Sue Vogel; Nicholas Laluk; Rachael Biggs; Robert Lefevre; Richard Gerhart; Salek Shafiqullah; Sara Dechter; Sarah Davis; Sharon Biedenbender; Tami Emmett; Terry Austin; William Gillespie; Yolynda Begay

    2013-01-01

    The U.S. Department of Agriculture, Forest Service, Coronado National Forest prepared this programmatic environmental impact statement to disclose the potential effects of a proposed action to revise the "Coronado National Forest Land and Resource Management Plan" (1986, as amended). The Coronado comprises 1,783,639 acres, most of which are located in...

  8. Deforestation and forest fires in Roraima and their relationship with phytoclimatic regions in the northern Brazilian Amazon.

    Science.gov (United States)

    Barni, Paulo Eduardo; Pereira, Vaneza Barreto; Manzi, Antonio Ocimar; Barbosa, Reinaldo Imbrozio

    2015-05-01

    Deforestation and forest fires in the Brazilian Amazon are a regional-scale anthropogenic process related to biomass burning, which has a direct impact on global warming due to greenhouse gas emissions. Containment of this process requires characterizing its spatial distribution and that of the environmental factors related to its occurrence. The aim of this study is to investigate the spatial and temporal distribution of deforested areas and forest fires in the State of Roraima from 2000 to 2010. We mapped deforested areas and forest fires using Landsat images and associated their occurrence with two phytoclimatic zones: zone with savanna influence (ZIS), and zone without savanna influence (ZOS). Total deforested area during the interval was estimated at 3.06 × 10(3) km(2) (ZIS = 55 %; ZOS = 45 %) while total area affected by forest fires was estimated at 3.02 × 10(3) km(2) (ZIS = 97.7 %; ZOS = 2.3 %). Magnitude of deforestation in Roraima was not related to the phytoclimatic zones, but small deforested areas (≤17.9 ha) predominated in ZOS while larger deforestation classes (>17.9 ha) predominated in ZIS, which is an area with a longer history of human activities. The largest occurrence of forest fires was observed in the ZIS in years with El Niño events. Our analysis indicates that the areas most affected by forest fires in Roraima during 2000-2010 were associated with strong climatic events and the occurrence these fires was amplified in ZIS, a sensitive phytoclimatic zone with a higher risk of anthropogenic fires given its drier climate and open forest structure.

  9. A Framework for Evaluating Forest Conservation Implications of Community-based Capacity Building: Experiences from the Northern Bolivian Amazon

    Directory of Open Access Journals (Sweden)

    Kelly Biedenweg

    2012-01-01

    Full Text Available Capacity-building projects in forest-based communities are implemented by governments, cooperatives, and non-government organisations to encourage sustainable management of community forests. While such projects are regularly evaluated on a case-by-case basis, they are rarely subjected to a landscape-level examination to explore conservation implications. To understand how environmental capacity-building projects address regional conservation goals, an interdisciplinary framework was developed to highlight the thematic focus, the geographic distribution, and the degree of community participation in environmental capacity-building projects. We demonstrate how the framework can be used by characterising projects in campesino communities in the Amazonian department of Pando, Bolivia, that were active during 2006-2008. While projects were too recent to affect forest cover, we describe how the framework elucidates three project themes (timber, Brazil nut, and agroforestry management; that project distribution was largely related to land tenure security, proximity to town, historical relationships, and motorised access; and that capacity-building strategies varied in participation, depending on thematic content and federal requirements for specific resources. We then discuss how the framework can be used to analyse forest cover implications over many years. Understanding the combination of thematic focus, geographic distribution, and degree of participation in project strategies offers a foundation for understanding how capacity-building initiatives can influence forest landscapes.

  10. It Takes a Rooted Village: Networked Resistance, Connected Communities, and Adaptive Responses to Forest Tenure Reform in Northern Thailand

    Directory of Open Access Journals (Sweden)

    Kimberly Roberts

    2016-06-01

    Full Text Available Conflicts persist between forest dwelling communities and advocates of forest conservation. In Thailand, a community forestry bill and national park expansion initiatives leave little space for communities. The article analyzes the case of the predominantly ethnic Black Lahu village of Huai Lu Luang in Chiang Rai province that has resisted the threats posed by a community forestry bill and a proposed national park. The villagers reside on a national forest reserve and have no de jure rights to the land. This article argues, however, that through its network rooted in place and connected to an assemblage of civil society, local government, and NGOs, Huai Lu Luang has been able to stall efforts by the Thai government that would detrimentally impact their use of and access to forest resources. Their resistance is best understood not in isolation – as one victimized community resisting threats to their livelihoods – but in connection to place, through dynamic assemblages. A ‘rooted’ networks approach follows the connections and nodes of Huai Lu Luang’s network that influence and aid the village’s attempts to resist forest tenure reform.

  11. Forest-atmosphere BVOC exchange in diverse and structurally complex canopies: 1-D modeling of a mid-successional forest in northern Michigan

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, Alexander M.; Cheng, Susan J.; Ashworth, Kirsti; Guenther, Alex B.; Hardiman, Brady; Bohrer, Gil; Steiner, A. L.

    2015-11-01

    Foliar emissions of biogenic volatile organic compounds (BVOC)dimportant precursors of tropospheric ozone and secondary organic aerosolsdvary widely by vegetation type. Modeling studies to date typi-cally represent the canopy as a single dominant tree type or a blend of tree types, yet many forests are diverse with trees of varying height. To assess the sensitivity of biogenic emissions to tree height vari-ation, we compare two 1-D canopy model simulations in which BVOC emission potentials are homo-geneous or heterogeneous with canopy depth. The heterogeneous canopy emulates the mid-successional forest at the University of Michigan Biological Station (UMBS). In this case, high-isoprene-emitting fo-liage (e.g., aspen and oak) is constrained to the upper canopy, where higher sunlight availability increases the light-dependent isoprene emission, leading to 34% more isoprene and its oxidation products as compared to the homogeneous simulation. Isoprene declines from aspen mortality are 10% larger when heterogeneity is considered. Overall, our results highlight the importance of adequately representing complexities of forest canopy structure when simulating light-dependent BVOC emissions and chemistry.

  12. A Comprehensive Fusion Liaison Officer Program: The Arizona Model

    Science.gov (United States)

    2015-03-01

    TLO) Program has become an institution that is relied upon by pm1icipant jurisdictions for intelligence and information sharing between federal, state...vetted-out partners throughout the public safety community to assist jurisdictions in addressing many high-risk events and incidents. In the...State University of New York College (Cortland), 1990 M.A., Northern Arizona University , 1999 Submitted in partial fulfillment of the

  13. Influence of multi-source and multi-temporal remotely sensed and ancillary data on the accuracy of random forest classification of wetlands in northern Minnesota

    Science.gov (United States)

    Corcoran, Jennifer M.; Knight, Joseph F.; Gallant, Alisa L.

    2013-01-01

    Wetland mapping at the landscape scale using remotely sensed data requires both affordable data and an efficient accurate classification method. Random forest classification offers several advantages over traditional land cover classification techniques, including a bootstrapping technique to generate robust estimations of outliers in the training data, as well as the capability of measuring classification confidence. Though the random forest classifier can generate complex decision trees with a multitude of input data and still not run a high risk of over fitting, there is a great need to reduce computational and operational costs by including only key input data sets without sacrificing a significant level of accuracy. Our main questions for this study site in Northern Minnesota were: (1) how does classification accuracy and confidence of mapping wetlands compare using different remote sensing platforms and sets of input data; (2) what are the key input variables for accurate differentiation of upland, water, and wetlands, including wetland type; and (3) which datasets and seasonal imagery yield the best accuracy for wetland classification. Our results show the key input variables include terrain (elevation and curvature) and soils descriptors (hydric), along with an assortment of remotely sensed data collected in the spring (satellite visible, near infrared, and thermal bands; satellite normalized vegetation index and Tasseled Cap greenness and wetness; and horizontal-horizontal (HH) and horizontal-vertical (HV) polarization using L-band satellite radar). We undertook this exploratory analysis to inform decisions by natural resource managers charged with monitoring wetland ecosystems and to aid in designing a system for consistent operational mapping of wetlands across landscapes similar to those found in Northern Minnesota.

  14. LiDAR-derived spatial models of hydrological and biogeochemical source areas to improve estimates of terrestrial-aquatic mercury export in northern forested landscapes

    Science.gov (United States)

    Richardson, M. C.; Mitchell, C. P.; Branfireun, B. A.; Kolka, R. K.; Fortin, M.

    2010-12-01

    Recent research on watershed mercury (Hg) and dissolved organic carbon (DOC) cycling in headwater research catchments in south-central Ontario, northwestern Ontario and northern Minnesota points to the critical role of discrete landscape elements in dictating rainfall-runoff response and the mobilization of DOC, Hg and methyl-mercury (MeHg) to downstream surface-waters. An overview of this research will be presented, emphasising two newly developed techniques used to extract hydrological and biogeochemical sources areas from airborne Light Detection and Ranging (LiDAR) surveys. First, hydrogeomorphic edge-detection was used to partition the landscape into discrete functional units based on local drainage conditions. From this initial landscape segmentation, forested wetlands and non-wetland saturation prone depressional areas were classified and extracted using classification and regression tree models based on LiDAR-derived geomorphic indices aggregated to the scale of individual landscape elements. Following this procedure, a characteristic morphology analysis was conducted from LiDAR bare-earth returns to quantitatively define the upland-peatland interfaces within all peatlands greater than 0.2 ha. These two terrain analysis techniques produced a number of functionally different landscape element classes that were subsequently used in the south-central Ontario study sites to test statistical models of terrestrial-aquatic fluxes of DOC, total Hg and MeHg over different time-scales. The regression models indicate that functional differences exist among landscape element classes with respect to their solute source-strengths and runoff generating potentials, and showed marked improvements over previous landscape models of hydrological and biogeochemical source areas in northern forested regions. LiDAR remote sensing can therefore be used to refine estimates of biogeochemical transformations and solute transport at the landscape scale, thus improving our

  15. Fine roots are the dominant source of recalcitrant plant litter in sugar maple-dominated northern hardwood forests.

    Science.gov (United States)

    Xia, Mengxue; Talhelm, Alan F; Pregitzer, Kurt S

    2015-11-01

    Most studies of forest litter dynamics examine the biochemical characteristics and decomposition of leaf litter, but fine roots are also a large source of litter in forests. We quantified the concentrations of eight biochemical fractions and nitrogen (N) in leaf litter and fine roots at four sugar maple (Acer saccharum)-dominated hardwood forests in the north-central United States. We combined these results with litter production data to estimate ecosystem biochemical fluxes to soil. We also compared how leaf litter and fine root biochemistry responded to long-term simulated N deposition. Compared with leaf litter, fine roots contained 2.9-fold higher acid-insoluble fraction (AIF) and 2.3-fold more condensed tannins; both are relatively difficult to decompose. Comparatively, leaf litter had greater quantities of more labile components: nonstructural carbohydrates, cellulose and soluble phenolics. At an ecosystem scale, fine roots contributed over two-thirds of the fluxes of AIF and condensed tannins to soil. Fine root biochemistry was also less responsive than leaf litter to long-term simulated N deposition. Fine roots were the dominant source of difficult-to-decompose plant carbon fractions entering the soil at our four study sites. Based on our synthesis of the literature, this pattern appears to be widespread in boreal and temperate forests.

  16. Ranging behavior of eastern hoolock gibbon (Hoolock leuconedys) in a northern montane forest in Gaoligongshan, Yunnan, China.

    Science.gov (United States)

    Zhang, Dao; Fei, Han-Lan; Yuan, Sheng-Dong; Sun, Wen-Mo; Ni, Qing-Yong; Cui, Liang-Wei; Fan, Peng-Fei

    2014-04-01

    Generally, food abundance and distribution exert important influence on primate ranging behavior. Hoolock gibbons (genus Hoolock) live in lowland and montane forests in India, Bangladesh, Myanmar and China. All information about hoolock gibbons comes from studies on western hoolock gibbons (Hoolock hoolock) living in lowland forest. Between August 2010 and September 2011, we studied the ranging behavior of one habituated group of eastern hoolock gibbon (H. leuconedys) living in a seasonal montane forest in Gaoligongshan, Yunnan, China. Results show that the study group did not increase foraging effort, calculated in this study as the daily path length, when fruit was less available. Instead, the gibbons fed more on leaves and decreased traveling to conserve energy. They relied heavily on a single food species in most study months which was patchily distributed within their total (14-month) home range, and during most months they used only a small portion of their total home range. In order to find enough food, the group shifted its monthly home range according to the seasonal availability of food species. To satisfy their annual food requirements, they occupied a total home range of 93 ha. The absence of neighboring groups of gibbons and the presence of tsaoko cardamom (Amomum tsaoko) plantations may also have influenced the ranging behavior of the group. Further long-term studies of neighboring groups living in intact forests are required to assess these effects.

  17. Influence of competition and age on tree growth in structurally complex old-growth forests in northern Minnesota, USA

    Science.gov (United States)

    Tuomas Aakala; Shawn Fraver; Anthony W. D' Amato; Brian J. Palik

    2013-01-01

    Factors influencing tree growth in structurally complex forests remain poorly understood. Here we assessed the influence of competition on Pinus resinosa (n = 224) and Pinus strobus (n = 90) growth in four old-growth stands in Minnesota, using mixed effects models. A subset of trees, with...

  18. Mammal indicator species for protected areas and managed forests in a landscape conservation area in northern India

    Science.gov (United States)

    Pradeep K. Mathur; Harish Kumar; John F. Lehmkuhl; Anshuman Tripathi; Vishwas B. Sawarkar; Rupak. De

    2010-01-01

    There is a realization that managed forests and other natural areas in the landscape matrix can and must make significant contributions to biodiversity conservation. Often, however, there are no consistent baseline vegetation or wildlife data for assessing the status of biodiversity elements across protected and managed areas for conservation planning, nor is there a...

  19. SUPERSTITION WILDERNESS, ARIZONA.

    Science.gov (United States)

    Peterson, Donald W.; Jinks, Jimmie E.

    1984-01-01

    On the basis of geologic studies and mineral evaluations most of the Superstition Wilderness and adjoining areas are judged to have little promise for occurrence of mineral resources. However, two areas in an east-trending zone near the southern margin of the area, marked by spotty occurrences of mineralized rock, prospect pits, and a band of geochemical anomalies that coincides with aligned magnetic anomalies, are considered to have probable mineral-resource potential. This zone lies within about 6 mi of two productive mines in Arizona's great copper belt, and the trend of the zone is parallel to many of the significant mineralized structures of this belt. A small isolated uranium anomaly was found in the northeastern part of the wilderness, but no evidence of other energy resources, such as petroleum, coal, or geothermal, was found.

  20. Soil and saproxylic species (Coleoptera, Collembola, Araneae in primeval forests from the Northern part of South-Easthern Carpathians

    Directory of Open Access Journals (Sweden)

    Eugen Nițu

    2009-12-01

    Full Text Available In 2006-2007 we carried out faunal investigations in the vernal, estival and autumnal seasons in the scientific reserve "Codrul Secular Giumalău" using quantitative sampling methods. We identified 189 species of Coleoptera, 70 of Collembola and 20 of Araneae. Of these, 11 phytophagous, 18 myceto/xylo-mycetophagous, 9 mixophagous, 18 xylo- and cambio-xylemophagous, 38 saproxylophagous, 125 (55 Coleoptera, 70 Collembola detritivorous (sapro-, copro- and necrophagous, 60 (40 Coleoptera, 20 Aranea predators/parasitoids. Hymenaphorura polonica Pomorski, 1990 (Collembola, and Leiodes rhaeticus Erichson, 1845 (Coleoptera, Leiodidae, are recorded for the first time in the Romanian fauna. The rare species and characteristic species for the old primeval spruce forests are analysed for each studied taxonomic group. The species richness and faunal diversity from the Giumalău primeval spruce forest are compared with those of other very well preserved forests from the Carpathians scientific reserves (Codrul Secular Slătioara, Pietrosul Rodnei. The species abundances were used to compute the similarity indexes between the sampled sectors of forest and to perform Cluster Analysis. We observed that the dead wood in the 2nd-6th phases of decomposition has a great influence not only on the saproxylic species but also on the soil fauna like ground beetles (Carabidae that use the logs as ecologic microrefuges (winter refugees or diurnal refugees. The structure of the soil fauna is influenced by wood extraction from the forest ecosystem or by natural perturbations, this consisting in the appearance of opportunistic species as Orchesella pontica (Collembola and in decreasing of species richness of Carabidae (Coleoptera.

  1. Soil and saproxylic species (Coleoptera, Collembola, Araneae in primeval forests from the northern part of South-Easthern Carpathians

    Directory of Open Access Journals (Sweden)

    Eugen Nitu

    2009-11-01

    Full Text Available In 2006-2007 we carried out faunal investigations in the vernal, estival and autumnal seasons in the scientific reserve "Codrul Secular Giumalãu" using quantitative sampling methods. We identified 189 species of Coleoptera, 70 of Collembola and 20 of Araneae. Of these, 11 phytophagous, 18 myceto/xylo-mycetophagous,9 mixophagous, 18 xylo- and cambio-xylemophagous, 38 saproxylophagous,125 (55 Coleoptera, 70 Collembola detritivorous (sapro-, copro- andnecrophagous, 60 (40 Coleoptera, 20 Aranea predators/parasitoids. Hymenaphorura polonica Pomorski, 1990 (Collembola, and Leiodes rhaeticus Erichson, 1845 (Coleoptera, Leiodidae, are recorded for the first time in the Romanian fauna. The rare species and characteristic species for the old primeval spruce forests are analysed for each studied taxonomic group. The species richness and faunal diversity from the Giumalãu primeval spruce forest are compared with those of other very well preserved forests from the Carpathians scientific reserves (Codrul Secular Slãtioara,Pietrosul Rodnei. The species abundances were used to compute the similarity indexes between the sampled sectors of forest and to perform Cluster Analysis. We observed that the dead wood in the 2nd-6th phases of decomposition has a great influence not only on the saproxylic species but also on the soil fauna like ground beetles(Carabidae that use the logs as ecologic microrefuges (winter refugees or diurnal refugees. The structure of the soil fauna is influenced by wood extraction from the forest ecosystem or by natural perturbations, this consisting in the appearance of opportunistic species as Orchesella pontica (Collembola and in decreasing ofspecies richness of Carabidae (Coleoptera.

  2. Relative impact of previous disturbance history on the likelihood of additional disturbance in the Northern United States Forest Service USFS Region

    Science.gov (United States)

    Hernandez, A. J.

    2015-12-01

    The Landsat archive is increasingly being used to detect trends in the occurrence of forest disturbance. Beyond information about the amount of area affected, forest managers need to know if and how disturbance regimes change. The National Forest System (NFS) has developed a comprehensive plan for carbon monitoring that requires a detailed temporal mapping of forest disturbances across 75 million hectares. A long-term annual time series that shows the timing, extent, and type of disturbance beginning in 1990 and ending in 2011 has been prepared for several USFS Regions, including the Northern Region. Our mapping starts with an automated detection of annual disturbances using a time series of historical Landsat imagery. Automated detections are meticulously inspected, corrected and labeled using various USFS ancillary datasets. The resulting maps of verified disturbance show the timing and types are fires, harvests, insect activity, disease, and abiotic (wind, drought, avalanche) damage. Also, the magnitude of each change event is modeled in terms of the proportion of canopy cover lost. The sequence of disturbances for every pixel since 1990 has been consistently mapped and is available across the entirety of NFS. Our datasets contain sufficient information to describe the frequency of stand replacement, as well as how often disturbance results in only a partial loss of canopy. This information provides empirical insight into how an initial disturbance may predispose a stand to further disturbance, and it also show a climatic signal in the occurrence of processes such as fire and insect epidemics. Thus, we have the information to model the likelihood of occurrence of certain disturbances after a given event (i.e. if we have a fire in the past what does that do to the likelihood of occurrence of insects in the future). Here, we explore if previous disturbance history is a reliable predictor of additional disturbance in the future and we present results of applying

  3. Effects of Northern red oak (Quercus rubra L. and sessile oak (Quercus petraea (Mattusch. Liebl. on the forest soil chemical properties

    Directory of Open Access Journals (Sweden)

    Miltner Stanislav

    2016-09-01

    Full Text Available Northern red oak (Quercus rubra L. is one of the most important introduced tree species in the Czech Republic, occupying about 6,000 ha with ca. 900,000 m3 of the standing volume. The presented study aims to evaluate its soil forming effects on natural oak sites. Soil chemistry of the upper soil layers (F+H, Ah, B horizons was studied in three pairs of stands of both species. In each stand, four bulk samples were taken separately for particular horizons, each consisting of 5 soil-borer cores. The soil characteristics analysed were: pH (active and potential, soil adsorption complex characteristics (content of bases, exchangeable cation capacity, base saturation, exchangeable acidity (exchangeable Al and H, total carbon and nitrogen content, and plant available nutrients content (P, K, Ca, Mg. Total macronutrient content (P, K, Ca, Mg was analysed only in holorganic horizons. Results confirmed acidification effects of red oak on the upper forest soil layers such as decreased pH, base content, base saturation, all nutrient contents in total as well as plant-available form and increased soil exchangeable acidity (exchangeable Al in comparison to the sessile oak stands, especially in holorganic horizons and in the uppermost mineral layer (Ah horizon. Northern red oak can be considered as a slightly site-soil degrading species in the studied sites and environmental conditions in comparison to native oak species.

  4. Spatial Enhancement of MODIS-based Images of Leaf Area Index: Application to the Boreal Forest Region of Northern Alberta, Canada

    Directory of Open Access Journals (Sweden)

    Charles P.-A. Bourque

    2010-01-01

    Full Text Available Leaf area index (LAI is one of the most commonly used ecological variables in describing forests. Since 2000, 1-km resolution Moderate Resolution Imaging Spectroradiometer (MODIS-based 8-day composites of LAI have been operationally available from the National Aeronautics and Space Administration (NASA, USA, at no cost to the user. In this paper, we present a simple protocol to enhance the spatial resolution of NASA-produced LAI composites to 250-m resolution. This is done by fusing MODIS-based estimates of enhanced vegetation index (EVI, consisting of 16-day 250-m resolution composites (also from NASA, with estimates of LAI. We apply the protocol to derive 250-m resolution maps of LAI for the boreal forest region of northern Alberta, Canada. Data fusion was possible in this study because of the inherent linear correlation that exists between EVI and LAI for the April to October growing period of 2005–2008, producing r2-values of 0.85–0.95 and p-values < 0.0001. Comparison of MODIS-based LAI with field-based measurements using the Tracing Radiation and Architecture of Canopies (TRAC sensor and LAI-2000 Plant Canopy Analyzer showed reasonable agreement across values; statistical comparison of LAI data points produced an r2-value of 0.71 and a p-value < 0.0001. Seventy one percent of MODIS-based LAI were within ±20% of field estimates.

  5. Effect of livestock grazing and human uses on herbaceous species diver-sity in oriental beech (Fagus orientalis Lipsky) forests, Guilan, Masal, northern Iran

    Institute of Scientific and Technical Information of China (English)

    Sepide Sadat Ebrahimi; Hassan Pourbabaei; David Potheir; Ali Omidi; Javad Torkaman

    2014-01-01

    Plant diversity plays key ecological roles in forest ecosystems, including influencing succession, resilience and nutrient cycling. This study was conducted to investigate the effect of livestock grazing and human uses on herbaceous species diversity. We surveyed 50 ha of pro-tected area and 50 ha of unprotected area to evaluate herbaceous species diversity in oriental beech (Fagus orientalis Lipsky) forests in northern Iran. We calculated and compared three indices each of diversity and evenness, and species richness between the two areas. Herbaceous cover was higher in the unprotected area while leaf litter depth and tree canopy cover were higher in the protected area. The diversity indices, H (Shan-non-Wiener index ), N1 (McArthur index), N2 (Hill΄s index), EQ (Modified Nee index), Evar (Smith-Wilson index), E5 (modified index of Hill) and R=S (species richness) and species richness R=S were greater in the protected area than in the unprotected area, suggesting that protection from grazing results in increased numbers of plants and species. The effect of land protection on plant diversity was more pronounced for evenness than for species richness and the positive correlation between diversity and even-ness indices was higher than that between diversity and richness.

  6. Short-Term Response of Sasa Dwarf Bamboo to a Change of Soil Nitrogen Fertility in a Forest Ecosystem in Northern Hokkaido, Japan.

    Science.gov (United States)

    Watanabe, Tsunehiro; Fukuzawa, Karibu; Shibata, Hideaki

    2016-04-14

    In forest ecosystems, a change of soil nitrogen (N) cycling after disturbance is regulated by various factors. Sasa dwarf bamboo (hereafter referred to as Sasa) is an understory plant that grows thickly on the forest floor in northern Hokkaido, Japan. However, the ecosystem function of Sasa after disturbances in the soil N cycling is not fully understood. The purpose of this study was to determine the short-term response of Sasa to a change of soil N fertility. Biomass, litterfall, litter decomposition, soil N pool, and N leaching from soil were measured in control, and low- (5 g N m(-2) year(-1)) and high-N (15 g N m(-2) year(-1)) addition plots. Sasa immobilized much N as the soil N fertility increased. However, the leaf N concentration in aboveground biomass did not increase, suggesting that the N in leaves was maintained because of the increase of leaf biomass. As a result, the decomposition and mineralization rates of the produced litter before and after N addition were comparable among plots, even though the soil inorganic N fertility increased greatly. These results suggest that immediate response of Sasa to an increase of soil inorganic N mitigates the excess N leaching from soil.

  7. After Returning Farmland To Forests Northern Shaanxi Hilly Rural Settlements Update%退耕还林后陕北丘陵区乡村聚落更新

    Institute of Scientific and Technical Information of China (English)

    贺文敏; 王军

    2016-01-01

    In Northern Shaanxi hily area the most prominent problem is the ecological environment degradation and rural poverty. Since the implementation of the returning farmland to forest, a huge impact on the Northern Shaanxi hily area, resulting the rural settlements updating in the area. Mainly in two aspects of the non-spatial dimensions and spatial dimensions: the improvement of ecological environment, production and lifestyle changes, improvement of living environment and the traditional concept of social change—non-spatial dimensions; rural settlement location,size and layout changes,rural settlement development model update and Architectural style courtyard and single unit transition—spatial dimensions.Thus, in Northern Shaanxi hily areas rural settlement construction began showing a new vitality.%陕北丘陵区面临最突出的问题是生态环境的退化和农民的贫困。退耕还林实施后,对陕北丘陵区产生了巨大的影响,导致该地区乡村聚落的更新。主要表现在非空间维度与空间维度两大方面:生态环境改善,生产生活方式转变,人居环境改善及社会传统观念转变——非空间维度;乡村聚落选址、规模及布局方式变化,乡村聚落模式更新及建筑院落与单体样式转型——空间维度。由此,陕北丘陵区乡村聚落的营建开始呈现出新的活力。

  8. Degradation of the northern paraná landscape: a study on forest fragments/ Degradação da paisagem norte-paranaense: um estudo de fragmentos florestais

    Directory of Open Access Journals (Sweden)

    Efraim Rodrigues

    2002-05-01

    Full Text Available Due to a fast occupation process, nearly all of the native vegetal covering of northern Paraná was devastated. Considering the lack of basic studies that support the management of forest remainders, this dissertation studies the forest fragmentation of the landscape in a transect of 180 km (between Maringá and Jacarezinho, considering a time and/or age of occupation gradient. One has adopted the hypothesis that the landscape to west, colonized from 1930 (Londrina and 1947 (Maringá, suffered smaller degradation in a comparison with what happened in the landscape situated further to east (and colonized in the mid 19th century and early 20th century. Results demonstrated that the initial hypothesis should be refute. Historical and factors socioeconomic influenced the occupation way and, consequently, the distribution of the forest fragments in the landscape.Devido ao rápido processo de ocupação, quase toda cobertura vegetal nativa do Norte do Paraná foi devastada. Considerando a necessidade de estudos básicos que dêem suporte ao manejo de remanescentes florestais, este trabalho estuda a fragmentação florestal da paisagem num transecto de 180 km (entre Jacarezinho e Maringá. Adotou-se a hipótese de que a paisagem mais a oeste – colonizada a partir de 1930 (Londrina e 1947 (Maringá – sofreu menor degradação antrópica, em comparação a paisagem, situada mais à leste (colonizada em meados do século XIX e início do século XX. Os resultados demonstraram que a hipótese inicial deve ser refutada. Fatores históricos e socioeconômicos influenciaram o modo de ocupação e conseqüentemente, a distribuição dos fragmentos florestais na paisagem.

  9. Preliminary Facies Reconstruction of a Late Pleistocene Cypress Forest Discovered on the Northern Gulf of Mexico Continental Shelf

    Science.gov (United States)

    Gonzalez Rodriguez, S. M.; Bentley, S. J.; DeLong, K. L.; Xu, K.; Caporaso, A.; Obelcz, J. B.; Harley, G. L.; Reese, C. A.; Truong, J. T.

    2016-12-01

    We are investigating the origin and preservation of an ancient bald cypress forest (Taxodium distichum) discovered on the continental shelf seafloor, offshore of Gulf Shores, Alabama, USA, in 20 m water depth. The forest was likely buried in the late Pleistocene, possibly exhumed by Hurricane Ivan in 2004, and is now exposed as stumps in life position with little evidence of decay before recent marine exposure. Radiocarbon analyses show that the forest age is near (and in some cases beyond) the limits of 14C dating, at least 41-45 ky BP. In August 2015 and July 2016, submersible vibracores (up to 5 m in length) were collected. Ongoing core analyses include: organic content (loss on ignition), granulometry, and core logging using a Geotek Multi Sensor Core Logger to generate imagery, bulk density, and x-ray fluorescence data. To bolster 14C analyses, cores collected in 2016 are presently being dated using optically stimulated luminescence. Local stratigraphy consists of a surface facies of Holocene transgressive sands, underlain by possible estuarine sediments of interbedded sand and mud (potentially Holocene or Pleistocene), overlying a swamp or delta plain facies (likely Pleistocene) containing woody debris and mud. Deeper woody facies are thought to include the soil horizons of the ancient cypress forest. Cores collected in 2016 revealed a Pleistocene paleosol beneath Holocene sands in a nearby trough. Elevation differences between swamp and paleosol horizons will be evaluated from bathymetric and subbottom data, to help characterize the preserved ancient landscape. Initial interpretation based on close proximity of Pleistocene swamp and oxidized paleosol sediments, and regional geomorphic gradients suggest that this relatively diverse assemblage of facies developed up to tens of km from the glacial-age coastline, and relatively rapid burial prevented erosion by coastal processes during the Holocene transgression thus preserving the tree stumps and wood debris.

  10. Forest biomass density across large climate gradients in northern South America is related to water availability but not with temperature

    Science.gov (United States)

    Cayuela, Luis; González-Caro, Sebastián; Aldana, Ana M.; Stevenson, Pablo R.; Phillips, Oliver; Cogollo, Álvaro; Peñuela, Maria C.; von Hildebrand, Patricio; Jiménez, Eliana; Melo, Omar; Londoño-Vega, Ana Catalina; Mendoza, Irina; Velásquez, Oswaldo; Fernández, Fernando; Serna, Marcela; Velázquez-Rua, Cesar; Benítez, Doris; Rey-Benayas, José M.

    2017-01-01

    Understanding and predicting the likely response of ecosystems to climate change are crucial challenges for ecology and for conservation biology. Nowhere is this challenge greater than in the tropics as these forests store more than half the total atmospheric carbon stock in their biomass. Biomass is determined by the balance between biomass inputs (i.e., growth) and outputs (mortality). We can expect therefore that conditions that favor high growth rates, such as abundant water supply, warmth, and nutrient-rich soils will tend to correlate with high biomass stocks. Our main objective is to describe the patterns of above ground biomass (AGB) stocks across major tropical forests across climatic gradients in Northwestern South America. We gathered data from 200 plots across the region, at elevations ranging between 0 to 3400 m. We estimated AGB based on allometric equations and values for stem density, basal area, and wood density weighted by basal area at the plot-level. We used two groups of climatic variables, namely mean annual temperature and actual evapotranspiration as surrogates of environmental energy, and annual precipitation, precipitation seasonality, and water availability as surrogates of water availability. We found that AGB is more closely related to water availability variables than to energy variables. In northwest South America, water availability influences carbon stocks principally by determining stand structure, i.e. basal area. When water deficits increase in tropical forests we can expect negative impact on biomass and hence carbon storage. PMID:28301482

  11. Forest biomass density across large climate gradients in northern South America is related to water availability but not with temperature.

    Science.gov (United States)

    Álvarez-Dávila, Esteban; Cayuela, Luis; González-Caro, Sebastián; Aldana, Ana M; Stevenson, Pablo R; Phillips, Oliver; Cogollo, Álvaro; Peñuela, Maria C; von Hildebrand, Patricio; Jiménez, Eliana; Melo, Omar; Londoño-Vega, Ana Catalina; Mendoza, Irina; Velásquez, Oswaldo; Fernández, Fernando; Serna, Marcela; Velázquez-Rua, Cesar; Benítez, Doris; Rey-Benayas, José M

    2017-01-01

    Understanding and predicting the likely response of ecosystems to climate change are crucial challenges for ecology and for conservation biology. Nowhere is this challenge greater than in the tropics as these forests store more than half the total atmospheric carbon stock in their biomass. Biomass is determined by the balance between biomass inputs (i.e., growth) and outputs (mortality). We can expect therefore that conditions that favor high growth rates, such as abundant water supply, warmth, and nutrient-rich soils will tend to correlate with high biomass stocks. Our main objective is to describe the patterns of above ground biomass (AGB) stocks across major tropical forests across climatic gradients in Northwestern South America. We gathered data from 200 plots across the region, at elevations ranging between 0 to 3400 m. We estimated AGB based on allometric equations and values for stem density, basal area, and wood density weighted by basal area at the plot-level. We used two groups of climatic variables, namely mean annual temperature and actual evapotranspiration as surrogates of environmental energy, and annual precipitation, precipitation seasonality, and water availability as surrogates of water availability. We found that AGB is more closely related to water availability variables than to energy variables. In northwest South America, water availability influences carbon stocks principally by determining stand structure, i.e. basal area. When water deficits increase in tropical forests we can expect negative impact on biomass and hence carbon storage.

  12. Soil nitrogen drives community-level phosphorus resorption in a co-limited system: evidence from a northern hardwood forest

    Science.gov (United States)

    See, C. R.; Yanai, R. D.

    2013-12-01

    Fertilization studies in northeastern forests suggest that forest productivity may be co-limited by nitrogen and phosphorus. Foliar nutrient resorption is a crucial conservation mechanism for plants. Resorption controls litterfall nutrient concentration, and litterfall is the largest aboveground nutrient flux in this system. Previous studies have attempted to link the foliar resorption of P to soil P status with mixed results. We propose that in an N and P co-limited system, foliar resorption of P may be linked to N availability. Here we compare the foliar chemistry of six hardwood tree species to soil chemistry across 18 plots in 6 stands in Bartlett Experimental Forest, New Hampshire. Resorption efficiency was calculated by species as the percent difference between green and senesced leaves. We weighted the resorption efficiencies for dominant tree species in each plot by their litterfall mass to create a community-level estimate of resorption for each plot. Estimates of soil N content to 30 centimeters in the mineral soil were strongly correlated with community-level estimates of both P resorption efficiency (p=0.002) and proficiency (p=0.006). At the population level, this trend was observed in four of the six tree species sampled. Neither N nor P resorption was correlated with any of the soil P fractions we examined. If N availability drives biological P conservation, it would provide an important mechanism for the coupled cycling of N and P in co-limited systems.

  13. IMPACTS OF INTERACTING ELEVATED ATMOSPHERIC CO2 AND O3 ON THE STRUCTURE AND FUNCTIONING OF A NORTHERN FOREST ECOSYSTEM: OPERATING AND DECOMMISSIONING THE ASPEN FACE PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    Burton, Andrew J. [Michigan Technological University; Zak, Donald R. [University of Michigan; Kubiske, Mark E. [USDA Forest Service; Pregitzer, Kurt S. [University of Idaho

    2014-06-30

    Two of the most important and pervasive greenhouse gases driving global change and impacting forests in the U.S. and around the world are atmospheric CO2 and tropospheric O3. As the only free air, large-scale manipulative experiment studying the interaction of elevated CO2 and O3 on forests, the Aspen FACE experiment was uniquely designed to address the long-term ecosystem level impacts of these two greenhouse gases on aspen-birch-maple forests, which dominate the richly forested Lake States region. The project was established in 1997 to address the overarching scientific question: “What are the effects of elevated [CO2] and [O3], alone and in combination, on the structure and functioning of northern hardwood forest ecosystems?” From 1998 through the middle of the 2009 growing season, we examined the interacting effects of elevated CO2 and O3 on ecosystem processes in an aggrading northern forest ecosystem to compare the responses of early-successional, rapid-growing shade intolerant trembling aspen and paper birch to those of a late successional, slower growing shade tolerant sugar maple. Fumigations with elevated CO2 (560 ppm during daylight hours) and O3 (approximately 1.5 x ambient) were conducted during the growing season from 1998 to 2008, and in 2009 through harvest date. Response variables quantified during the experiment included growth, competitive interactions and stand dynamics, physiological processes, plant nutrient status and uptake, tissue biochemistry, litter quality and decomposition rates, hydrology, soil respiration, microbial community composition and respiration, VOC production, treatment-pest interactions, and treatment-phenology interactions. In 2009, we conducted a detailed harvest of the site. The harvest included detailed sampling of a subset of trees by component (leaves and buds, fine branches, coarse branches and stem, coarse roots, fine roots) and excavation of soil to a depth of 1 m. Throughout the experiment, aspen and birch

  14. 234U/238U isotope data from groundwater and solid-phase leachate samples near Tuba City Open Dump, Tuba City, Arizona

    Science.gov (United States)

    Johnson, Raymond H.; Horton, Robert J.; Otton, James K.; Ketterer, Michael K.

    2012-01-01

    This report releases 234U/238U isotope data, expressed as activity ratios, and uranium concentration data from analyses completed at Northern Arizona University for groundwater and solid-phase leachate samples that were collected in and around Tuba City Open Dump, Tuba City, Arizona, in 2008.

  15. IMPACTS OF INTERACTING ELEVATED ATMOSPHERIC CO2 AND O3 ON THE STRUCTURE AND FUNCTIONING OF A NORTHERN FOREST ECOSYSTEM: OPERATING AND DECOMMISSIONING THE ASPEN FACE PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    Burton, Andrew J. [Michigan Technological University; Zak, Donald R. [University of Michigan; Kubiske, Mark E. [USDA Forest Service; Pregitzer, Kurt S. [University of Idaho

    2014-06-30

    Two of the most important and pervasive greenhouse gases driving global change and impacting forests in the U.S. and around the world are atmospheric CO2 and tropospheric O3. As the only free air, large-scale manipulative experiment studying the interaction of elevated CO2 and O3 on forests, the Aspen FACE experiment was uniquely designed to address the long-term ecosystem level impacts of these two greenhouse gases on aspen-birch-maple forests, which dominate the richly forested Lake States region. The project was established in 1997 to address the overarching scientific question: “What are the effects of elevated [CO2] and [O3], alone and in combination, on the structure and functioning of northern hardwood forest ecosystems?” From 1998 through the middle of the 2009 growing season, we examined the interacting effects of elevated CO2 and O3 on ecosystem processes in an aggrading northern forest ecosystem to compare the responses of early-successional, rapid-growing shade intolerant trembling aspen and paper birch to those of a late successional, slower growing shade tolerant sugar maple. Fumigations with elevated CO2 (560 ppm during daylight hours) and O3 (approximately 1.5 x ambient) were conducted during the growing season from 1998 to 2008, and in 2009 through harvest date. Response variables quantified during the experiment included growth, competitive interactions and stand dynamics, physiological processes, plant nutrient status and uptake, tissue biochemistry, litter quality and decomposition rates, hydrology, soil respiration, microbial community composition and respiration, VOC production, treatment-pest interactions, and treatment-phenology interactions. In 2009, we conducted a detailed harvest of the site. The harvest included detailed sampling of a subset of trees by component (leaves and buds, fine branches, coarse branches and stem, coarse roots, fine roots) and excavation of soil to a depth of 1 m. Throughout the experiment, aspen and birch

  16. Proceedings of the National Silviculture Workshop: Silvicultural Implications Of Section 4, NFMA 1976; Flagstaff, Arizona; September 26-30, 1977

    Science.gov (United States)

    Gary Cargill; Robert Gillespie; Wayne Mann; Bob Blomquist; Don Strode; Edward R. Schneegas; Charles Sundstrom; John F. Corliss; Bill Pint; William D. Zeedyk; Robert D. Pfister; Raymond C. Shearer; Andrew A. Leven; Robert R. Alexander; Roger E. Sandquist; Robert E. Stevens; Clark Row; Jim Sabin; LaMont Engle; Tom Greathouse

    1977-01-01

    The 1977 Silviculture Workshop was held in Flagstaff, Arizona, September 26-30, 1977. The objective of the meeting was to discuss the reforestation and maintenance of appropriate forest cover required by Section 4 of the National Forest Management Act of 1976. These proceedings include the presentations that were available for publication.

  17. Willow Fire Near Payson, Arizona

    Science.gov (United States)

    2004-01-01

    On July 3, 2004, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite acquired this image of the Willow fire near Payson, Arizona. The image is being used by the United States Department of Agriculture's Forest Service Remote Sensing Applications Center (RSAC). The image combines data from the visible and infrared wavelength regions to highlight: the burned areas in dark red; the active fires in red-orange; vegetation in green; and smoke in blue. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance. The U.S. Science Team is located at NASA's Jet Propulsion Laboratory (JPL), Pasadena, Calif. The Terra mission is part of NASA's Earth Science Enterprise, a long- term research effort dedicated to understanding the Earth as an integrated system and applying Earth System Science to improve prediction of climate, weather, and natural hazards using the unique vantage point of space. Size: 34 by 41

  18. The autotrophic contribution to soil respiration in a northern temperate deciduous forest and its response to stand disturbance.

    Science.gov (United States)

    Levy-Varon, Jennifer H; Schuster, William S F; Griffin, Kevin L

    2012-05-01

    The goal of this study was to evaluate the contribution of oak trees (Quercus spp.) and their associated mycorrhizal fungi to total community soil respiration in a deciduous forest (Black Rock Forest) and to explore the partitioning of autotrophic and heterotrophic respiration. Trees on twelve 75 × 75-m plots were girdled according to four treatments: girdling all the oaks on the plot (OG), girdling half of the oak trees on a plot (O50), girdling all non-oaks on a plot (NO), and a control (C). In addition, one circular plot (diameter 50 m) was created where all trees were girdled (ALL). Soil respiration was measured before and after tree girdling. A conservative estimate of the total autotrophic contribution is approximately 50%, as indicated by results on the ALL and OG plots. Rapid declines in carbon dioxide (CO(2)) flux from both the ALL and OG plots, 37 and 33%, respectively, were observed within 2 weeks following the treatment, demonstrating a fast turnover of recently fixed carbon. Responses from the NO and O50 treatments were statistically similar to the control. A non-proportional decline in respiration rates along the gradient of change in live aboveground biomass complicated partitioning of the overall rate of soil respiration and indicates that belowground carbon flux is not linearly related to aboveground disturbance. Our findings suggest that in this system there is a threshold disturbance level between 35 and 74% of live aboveground biomass loss, beyond which belowground dynamics change dramatically.

  19. Reduced snow cover alters root-microbe interactions and decreases nitrification rates in a northern hardwood forest.

    Science.gov (United States)

    Sorensen, Patrick O; Templer, Pamela H; Christenson, Lynn; Duran, Jorge; Fahey, Timothy; Fisk, Melany C; Groffman, Peter M; Morse, Jennifer L; Finzi, Adrien C

    2016-12-01

    Snow cover is projected to decline during the next century in many ecosystems that currently experience a seasonal snowpack. Because snow insulates soils from frigid winter air temperatures, soils are expected to become colder and experience more winter soil freeze-thaw cycles as snow cover continues to decline. Tree roots are adversely affected by snowpack reduction, but whether loss of snow will affect root-microbe interactions remains largely unknown. The objective of this study was to distinguish and attribute direct (e.g., winter snow- and/or soil frost-mediated) vs. indirect (e.g., root-mediated) effects of winter climate change on microbial biomass, the potential activity of microbial exoenzymes, and net N mineralization and nitrification rates. Soil cores were incubated in situ in nylon mesh that either allowed roots to grow into the soil core (2 mm pore size) or excluded root ingrowth (50 μm pore size) for up to 29 months along a natural winter climate gradient at Hubbard Brook Experimental Forest, NH (USA). Microbial biomass did not differ among ingrowth or exclusion cores. Across sampling dates, the potential activities of cellobiohydrolase, phenol oxidase, and peroxidase, and net N mineralization rates were more strongly related to soil volumetric water content (P forests. © 2016 by the Ecological Society of America.

  20. From missing source to missing sink: long-term changes in the nitrogen budget of a northern hardwood forest.

    Science.gov (United States)

    Yanai, Ruth D; Vadeboncoeur, Matthew A; Hamburg, Steven P; Arthur, Mary A; Fuss, Colin B; Groffman, Peter M; Siccama, Thomas G; Driscoll, Charles T

    2013-10-15

    Biogeochemical monitoring for 45 years at the Hubbard Brook Experimental Forest in New Hampshire has revealed multiple surprises, seeming contradictions, and unresolved questions in the long-term record of ecosystem nitrogen dynamics. From 1965 to 1977, more N was accumulating in living biomass than was deposited from the atmosphere; the "missing" N source was attributed to biological fixation. Since 1992, biomass accumulation has been negligible or even negative, and streamwater export of dissolved inorganic N has decreased from ~4 to ~1 kg of N ha(-1) year(-1), despite chronically elevated atmospheric N deposition (~7 kg of N ha(-1) year(-1)) and predictions of N saturation. Here we show that the ecosystem has shifted to a net N sink, either storing or denitrifying ~8 kg of N ha(-1) year(-1). Repeated sampling over 25 years shows that the forest floor is not detectably accumulating N, but the C:N ratio is increasing. Mineral soil N has decreased nonsignificantly in recent decades, but the variability of these measurements prevents detection of a change of <700 kg of N ha(-1). Whether the excess N is accumulating in the ecosystem or lost through denitrification will be difficult to determine, but the distinction has important implications for the local ecosystem and global climate.

  1. Forests of Kansas, 2013

    Science.gov (United States)

    D.M. Meneguzzo; B.J. Butler

    2014-01-01

    This resource update provides an overview of forest resource attributes for Kansas based on annual inventories conducted by the Forest Inventory and Analysis (FIA) program of the Northern Research Station (NRS) of the U.S. Forest Service. The estimates presented in this update are based on field data collected in 2009-2013 with comparisons made to data collected from...

  2. Kansas' Forest Resources, 2007

    Science.gov (United States)

    W.K. Moser; M.H. Hansen; R.L. Atchison

    2008-01-01

    This publication provides an overview of forest resource attributes for Kansas based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) program at the Northern Research Station of the U.S. Forest Service. These estimates, along with web-posted core tables, will be updated annually. For more information please refer to page 4 of this report....

  3. Forests of Kansas, 2014

    Science.gov (United States)

    D.M. Meneguzzo; S.J. Crocker

    2015-01-01

    This resource update provides an overview of forest resource attributes for Kansas based on annual inventories conducted by the Forest Inventory and Analysis (FIA) program of the Northern Research Station (NRS) of the U.S. Forest Service. The estimates presented in this update are based on field data collected in 2010-2014 with comparisons made to data collected from...

  4. Kansas' forest resources, 2012

    Science.gov (United States)

    W.K. Moser; P.D. Miles; R.A. Atchison

    2013-01-01

    This publication provides an overview of forest resource attributes for Kansas based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) program at the Northern Research Station of the U.S. Forest Service. These estimates, along with web-posted core tables, will be updated annually. For more information please refer to page 4 of this report....

  5. Kansas' forest resources, 2010

    Science.gov (United States)

    W.K. Moser; C.H. Barnett; C.M. Kurtz; R.A. Atchison

    2011-01-01

    This publication provides an overview of forest resource attributes for Kansas based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) program at the Northern Research Station of the U.S. Forest Service. These estimates, along with web-posted core tables, will be updated annually. For more information please refer to page 4 of this report....

  6. Kansas' forest resources, 2009

    Science.gov (United States)

    W.K. Moser; M.H. Hansen; C.H. Barnett; R.A. Atchison

    2010-01-01

    This publication provides an overview of forest resource attributes for Kansas based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) program at the Northern Research Station of the U.S. Forest Service. These estimates, along with web-posted core tables, will be updated annually. For more information please refer to page 4 of this report....

  7. Kansas' forest resources, 2011

    Science.gov (United States)

    W.K. Moser; D.E. Haugen; R.A. Atchison

    2012-01-01

    This publication provides an overview of forest resource attributes for Kansas based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) program at the Northern Research Station of the U.S. Forest Service. These estimates, along with web-posted core tables, will be updated annually. For more information please refer to page 4 of this report....

  8. Forests of Iowa, 2015

    Science.gov (United States)

    Mark D. Nelson; Matt Brewer; Dacia M. Meneguzzo; Kathryne. Clark

    2016-01-01

    This resource update provides an overview of forest resources in Iowa based on inventories conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program at the Northern Research Station in cooperation with the Iowa Department of Natural Resources. Estimates are based on field data collected using the FIA annualized sample design and are updated...

  9. Massachusetts' Forest Resources, 2006

    Science.gov (United States)

    Brett J. Butler; Charles Burnham; I. Ted Goodnight; Barbara O' Connell; Bryan Tirrell

    2008-01-01

    Table 1 and Figures 2 and 3 have been revised by the authors and these revisions were incorporated into the publication on May 27, 2008. This publication provides an overview of forest resource attributes for Massachusetts based on an annual inventory conducted by the Forest Inventory and Analysis program at the Northern Research Station of the U.S. Forest Service....

  10. Connecticut's Forest Resources, 2006

    Science.gov (United States)

    Brett J. Butler; I. Ted Goodnight; Helene F. Hochholzer; Barbara O' Connell; Bryan Tirrell

    2008-01-01

    Table 1 and Figures 2 and 3 have been revised by the authors and these revisions were incorporated into the publication on May 27, 2008. This publication provides an overview of forest resource attributes for Connecticut based on an annual inventory conducted by the Forest Inventory and Analysis program at the Northern Research Station of the U.S. Forest Service. These...

  11. Landscape pattern of seed banks and anthropogenic impacts in forested wetlands of the northern Mississippi River Alluvial Valley

    Science.gov (United States)

    Middleton, B.; Wu, X.B.

    2008-01-01

    Agricultural development on floodplains contributes to hydrologic alteration and forest fragmentation, which may alter landscape-level processes. These changes may be related to shifts in the seed bank composition of floodplain wetlands. We examined the patterns of seed bank composition across a floodplain watershed by looking at the number of seeds germinating per m2 by species in 60 farmed and intact forested wetlands along the Cache River watershed in Illinois. The seed bank composition was compared above and below a water diversion (position), which artificially subdivides the watershed. Position of these wetlands represented the most variability of Axis I in a Nonmetric Multidimensional Scaling (NMS) analysis of site environmental variables and their relationship to seed bank composition (coefficient of determination for Axis 1: r2 = 0.376; Pearson correlation of position to Axis 1: r = 0.223). The 3 primary axes were also represented by other site environmental variables, including farming status (farmed or unfarmed), distance from the mouth of the river, latitude, and longitude. Spatial analysis based on Mantel correlograms showed that both water-dispersed and wind/water-dispersed seed assemblages had strong spatial structure in the upper Cache (above the water diversion), bur the spatial structure of water-dispersed seed assemblage was diminished in the lower Cache (below the water diversion), which lost floodpulsing. Bearing analysis also Suggested that water-dispersal process had a stronger influence on the overall spatial pattern of seed assemblage in the upper Cache, while wind/water-dispersal process had a stronger influence in the lower Cache. An analysis of the landscapes along the river showed that the mid-lower Cache (below the water diversion) had undergone greater land cover changes associated with agriculture than did the upper Cache watershed. Thus, the combination of forest fragmentation and hydrologic changes in the surrounding landscape may

  12. Effects of climate, fire and vegetation development on Holocene changes in total organic carbon concentration in three boreal forest lakes in northern Sweden

    Directory of Open Access Journals (Sweden)

    P. Rosén

    2007-11-01

    Full Text Available Near infrared spectroscopy (NIRS, diatoms, pollen, charcoal, loss-on-ignition (LOI, and nutrient elements in lake sediments were used to assess important factors controlling Holocene changes in the total organic carbon (TOC concentration, pCO2, color and pH of lake water in three boreal forest lakes in northern Sweden. The results suggest that mire formation, fire frequency and humidity are the most important forcing factors on millennial timescales. Mires produce humic acids that become available to the lakes, whereas fires may reduce the pool of carbon in the catchments, and humidity controls the transportation of allochthonous carbon into the lakes. Vegetation development and temperature as sole factors are of minor importance for the TOC concentrations in these lakes on a millennial timescale. Two of the sites indicate that liming and possibly fish introduction and rotenone treatment in recent time has led to increased TOC, color and pH in the lake water, and changed the diatom community composition to an assemblage that has never been present before. Given the predicted climate change scenario that suggests a more humid climate, expanding mires and less frequent fires, our paleolimnological data suggest that TOC concentrations can be expected to increase in boreal forest lakes in the future. Since super-saturation and emission of CO2 from lakes is correlated to the TOC concentration of lake water, higher TOC concentrations may lead to increased emission of CO2 from lakes to the atmosphere.

  13. Landscape patterns of overstory litterfall and related nutrient fluxes in a cool-temperate forest watershed in northern Hokkaido,Japan

    Institute of Scientific and Technical Information of China (English)

    XU Xiao-niu; Hideaki SHIBATA

    2007-01-01

    Within a forested watershed at the Uryu Experimental Forest of Hokkaido University in northern Hokkaido, overstory litterfall and related nutrient fluxes were measured at different landscape zones over two years. The wetland zone covered with Picea glehnii pure stand. The riparian zone was deciduous broad-leaved stand dominated by Alnus hirsuta and Salix spp., while the mixture of deciduous broadleaf and evergreen conifer dominated by Betula platyphylla, Quercus crispula and Abies sachalinensis distributed on the upland zone.Annual litterfall averaged 1444, 5122, and 4123 kg·hm-2·a-1 in the wetland, riparian and upland zones, respectively. Litterfall production peaked in September-ctober,and foliage litter contributed the greatest amount (73.4%-87.6 %) of the annual total litterfall. Concentrations of nutrients analyzed in foliage litter of the dominant species showed a similar seasonal variation over the year except for N in P. Glehnii and A. Hirsuta. The nutrient fluxes for all elements analyzed were greatest on riparian zone and lowest in wetland zone. Nutrient fluxes via lit terfall followed the decreasing sequence: N (11-129 kg·hm-2·a-1) > Ca (9-69) > K (5-20) > Mg (3-15) > P (0.4-4.7) for all stands. Significant differences were found in litterfall production and nutrient fluxes among the different landscape components. There existed significantdif ferences in soil chemistry between the different landscape zones. The consistently low soil C:N ratios at the riparian zone might be due to the higher-quality litter inputs (largely N-fixing alder).

  14. Application of Satellite Solar-Induced Chlorophyll Fluorescence to Understanding Large-Scale Variations in Vegetation Phenology and Function Over Northern High Latitude Forests

    Science.gov (United States)

    Jeong, Su-Jong; Schimel, David; Frankenberg, Christian; Drewry, Darren T.; Fisher, Joshua B.; Verma, Manish; Berry, Joseph A.; Lee, Jung-Eun; Joiner, Joanna

    2016-01-01

    This study evaluates the large-scale seasonal phenology and physiology of vegetation over northern high latitude forests (40 deg - 55 deg N) during spring and fall by using remote sensing of solar-induced chlorophyll fluorescence (SIF), normalized difference vegetation index (NDVI) and observation-based estimate of gross primary productivity (GPP) from 2009 to 2011. Based on GPP phenology estimation in GPP, the growing season determined by SIF time-series is shorter in length than the growing season length determined solely using NDVI. This is mainly due to the extended period of high NDVI values, as compared to SIF, by about 46 days (+/-11 days), indicating a large-scale seasonal decoupling of physiological activity and changes in greenness in the fall. In addition to phenological timing, mean seasonal NDVI and SIF have different responses to temperature changes throughout the growing season. We observed that both NDVI and SIF linearly increased with temperature increases throughout the spring. However, in the fall, although NDVI linearly responded to temperature increases, SIF and GPP did not linearly increase with temperature increases, implying a seasonal hysteresis of SIF and GPP in response to temperature changes across boreal ecosystems throughout their growing season. Seasonal hysteresis of vegetation at large-scales is consistent with the known phenomena that light limits boreal forest ecosystem productivity in the fall. Our results suggest that continuing measurements from satellite remote sensing of both SIF and NDVI can help to understand the differences between, and information carried by, seasonal variations vegetation structure and greenness and physiology at large-scales across the critical boreal regions.

  15. Canopy-scale flux measurements and bottom-up emission estimates of volatile organic compounds from a mixed oak and hornbeam forest in northern Italy

    Directory of Open Access Journals (Sweden)

    W. J. F. Acton

    2015-10-01

    Full Text Available This paper reports the fluxes and mixing ratios of biogenically emitted volatile organic compounds (BVOCs 4 m above a mixed oak and hornbeam forest in northern Italy. Fluxes of methanol, acetaldehyde, isoprene, methyl vinyl ketone + methacrolein, methyl ethyl ketone and monoterpenes were obtained using both a proton transfer reaction-mass spectrometer (PTR-MS and a proton transfer reaction-time of flight-mass spectrometer (PTR-ToF-MS together with the methods of virtual disjunct eddy covariance (PTR-MS and eddy covariance (PTR-ToF-MS. Isoprene was the dominant emitted compound with a mean day-time flux of 1.9 mg m-2 h-1. Mixing ratios, recorded 4 m above the canopy, were dominated by methanol with a mean value of 6.2 ppbv over the 28 day measurement period. Comparison of isoprene fluxes calculated using the PTR-MS and PTR-ToF-MS showed very good agreement while comparison of the monoterpene fluxes suggested a slight over estimation of the flux by the PTR-MS. A basal isoprene emission rate for the forest of 1.7 mg m-2 h-1 was calculated using the MEGAN isoprene emissions algorithms (Guenther et al., 2006. A detailed tree species distribution map for the site enabled the leaf-level emissions of isoprene and monoterpenes recorded using GC-MS to be scaled up to produce a "bottom-up" canopy-scale flux. This was compared with the "top-down" canopy-scale flux obtained by measurements. For monoterpenes, the two estimates were closely correlated and this correlation improved when the plant species composition in the individual flux footprint was taken into account. However, the bottom-up approach significantly underestimated the isoprene flux, compared with the top-down measurements, suggesting that the leaf-level measurements were not representative of actual emission rates.

  16. Classification and ordination of understory vegetation using multivariate techniques in the Pinus wallichiana forests of Swat Valley, northern Pakistan

    Science.gov (United States)

    Rahman, Inayat Ur; Khan, Nasrullah; Ali, Kishwar

    2017-04-01

    An understory vegetation survey of the Pinus wallichiana-dominated temperate forests of Swat District was carried out to inspect the structure, composition and ecological associations of the forest vegetation. A quadrat method of sampling was used to record the floristic and phytosociological data necessary for the analysis using 300 quadrats of 10 × 10 m each. Some vegetation parameters viz. frequency and density for trees (overstory vegetation) as well as for the understory vegetation were recorded. The results revealed that in total, 92 species belonging to 77 different genera and 45 families existed in the area. The largest families were Asteraceae, Rosaceae and Lamiaceae with 12, ten and nine species, respectively. Ward's agglomerative cluster analysis for tree species resulted in three floristically and ecologically distinct community types along different topographic and soil variables. Importance value indices (IVI) were also calculated for understory vegetation and were subjected to ordination techniques, i.e. canonical correspondence analysis (CCA) and detrended correspondence analysis (DCA). DCA bi-plots for stands show that most of the stands were scattered around the centre of the DCA bi-plot, identified by two slightly scattered clusters. DCA for species bi-plot clearly identified three clusters of species revealing three types of understory communities in the study area. Results of the CCA were somewhat different from the DCA showing the impact of environmental variables on the understory species. CCA results reveal that three environmental variables, i.e. altitude, slope and P (mg/kg), have a strong influence on distribution of stands and species. Impact of tree species on the understory vegetation was also tested by CCA which showed that four tree species, i.e. P. wallichiana A.B. Jackson, Juglans regia Linn., Quercus dilatata Lindl. ex Royle and Cedrus deodara (Roxb. ex Lamb.) G. Don, have strong influences on associated understory vegetation. It

  17. Diffusivity Models and Greenhouse Gases Fluxes from a Forest, Pasture, Grassland and Corn Field in Northern Hokkaido, Japan

    Institute of Scientific and Technical Information of China (English)

    N.V.NKONGOLO; R.HATANO; V.KAKEMBO

    2010-01-01

    Information on the most influential factors determining gas flux from soils is needed in predictive models for greenhouse gases emissions.We conducted an intensive soil and air sampling along a 2 000 m transect extending from a forest,pasture,grassland and corn field in Shizunai,Hokkaido (Japan),measured CO2,CH4,N2O and NO fluxes and calculated soil bulk density (ρb),air-filled porosity (fa) and total porosity (φ).Using diffusivity models based on either fa alone or on a combination of fa and φ,we predicted two pore space indices:the relative gas diffusion coefficient (Ds/Do) and the pore tortuosity factor (τ).The relationships between pore space indices (Dg/Do and τ) and CO2,CH4,N2O and NO fluxes were also studied.Results showed that the grassland had the highest ρb while fa and φ were the highest in the forest.CO2,CH4,N2O and NO fluxes were the highest in the grassland while N2O dominated in the corn field.Few correlations existed between fa,φ,ρb and gases fluxes while all models predicted that Ds/Do and τ significantly correlated with CO2 and CH4 with correlation coefficient (τ) ranging from 0.20 to 0.80.Overall,diffusivity models based on fa alone gave higher Ds/Do,lower τ and higher R2 and better explained the relationship between pore space indices (Ds/Do and τ) and gases fluxes.Inclusion of Ds/Do and τ in predictive models will improve our understanding of the dynamics of greenhouse gas fluxes from soils.Ds/Do and τ can be easily obtained by measurements of soil air and water and existing diffusivity models.

  18. Regional Equivalent Water Thickness Modeling from Remote Sensing across a Tree Cover/LAI Gradient in Mediterranean Forests of Northern Tunisia

    Directory of Open Access Journals (Sweden)

    Hedia Chakroun

    2015-02-01

    Full Text Available The performance of vegetation indexes derived from moderate resolution imaging spectroradiometer (MODIS sensors is explored for drought monitoring in the forests of Northern Tunisia; representing a transition zone between the Mediterranean Sea and the Sahara Desert. We investigated the suitability of biomass and moisture vegetation indexes for vegetation water content expressed by the equivalent water thickness (EWT in a Mediterranean forest ecosystem with contrasted water budgets and desiccation rates. We proposed a revised EWT at canopy level (EWTCAN based on weekly field measurements of fuel moisture in seven species during the 2010 dry period; considering the mixture of plant functional types for water use (trees; shrubs and herbaceous layers and a varying vegetation cover. MODIS vegetation indexes computed and smoothed over the dry season were highly correlated with the EWTCAN. The performances of moisture indexes (Normalized Difference Infrared Index (NDII6 and NDII7; and Global Moisture Vegetation Index (GVMI6 and GVMI7 were comparable; whereas; for biomass vegetation indexes; Normalized Difference Vegetation Index (NDVI; Modified Soil Adjusted Vegetation Index (MSAVI and Adjusted Normalized Difference Vegetation Index (ANDVI performed better than Enhanced Vegetation Index (EVI and Soil Adjusted Vegetation Index (SAVI. We also identified the effect of Leaf Area Index (LAI on EWTCAN monitoring at the regional scale under the tree cover/LAI gradient of the region from relatively dense to open forest. Statistical analysis revealed a significant decreasing linear relationship; indicating that for LAI less than two; the greater the LAI; the less responsive are the vegetation indexes to changes in EWTCAN; whereas for higher LAI; its influence becomes less significant and was not considered in the inversion models based on vegetation indexes. The EWTCAN time-course from LAI-adapted inversion models; based on significantly-related vegetation

  19. The Uneven Performance of Arizona's Charter Schools

    Science.gov (United States)

    Chingos, Matthew M.; West, Martin R.

    2015-01-01

    Arizona enrolls a larger share of its students in charter schools than any other state in the country, but no comprehensive examination exists of the impact of those schools on student achievement. Using student-level data covering all Arizona students from 2006 to 2012, we find that the performance of charter schools in Arizona in improving…

  20. Bioecological peculiarities of mid-ripening varieties of strawberry (Fragaria ananassa Duch. in the northern part of the Forest-Steppe zone of Ukraine

    Directory of Open Access Journals (Sweden)

    В. В. Павлюк

    2016-05-01

    Full Text Available Purpose. Improvement of a range of strawberry varie­ties based on comprehensive study and introduction of new Ukrainian and West European cultivars. Methods. Cultivars and elite forms were studied using the methods of primary variety studying and state variety testing at three-year strawberry plantations of the Institute of Horticulture of the National Academy of Sciences of Ukraine (the city of Kyiv and its variety testing stations. Results. It was found that more frequent spring and summer droughts as well as black frosts in winter adversely affected the strawberry productivity. The best varieties were selected among new ones for the complex of traits, they included ‘Elegance’ from the Great Britain, ‘Gercules’ from Ukraine (both are dessert grapes, ‘Elsanta’ from Holland (for universal use, ‘Alba’ from Italia (as raw material. The highly adaptive and productive ‘Istochnik’ and ‘Festyvalna romashka’ varieties (as raw material are recommended for the north regions. Conclusions. In the context of profound climatic change, high-profitable cultivation of mid-ripening varieties and a strawberry as such in the Northern Forest-Steppe zone is expedient under controlled conditions – in high film tunnels, in hot-houses and under perennial irrigation that already has become the European tendency.

  1. Soil solution and sugar maple response to NH(4)NO (3) additions in a base-poor northern hardwood forest of Québec, Canada.

    Science.gov (United States)

    Moore, Jean-David; Houle, Daniel

    2009-08-01

    Nitrogen additions (NH4NO3) at rates of three- and ten-fold ambient atmospheric deposition (8.5 kg ha(-1) year(-1)) were realised in an acid- and base-poor northern hardwood forest of Québec, Canada. Soil solution chemistry, foliar chemistry, crown dieback and basal area growth of sugar maple (Acer saccharum Marsh.) were measured. Except for a transitory increase of NO3 and NH4 concentrations, there was no persistent increase in their level in soil solution 3 years after N treatments, with the exception of one plot out of three, that received the highest N addition, beginning to show persistent and high NO3 concentrations after 2 years of N additions. Three years of N additions have significantly increased the N DRIS index of sugar maple but not N foliar concentration. Potassium, Ca and Mn foliar concentrations, as well as P and Ca DRIS indices, decreased in treated plots after 3 years. No treatment effect was observed for basal area growth and dieback rate. One unexpected result was the significant decrease in foliar Ca even in the treated plots that received low N rates, despite the absence of significant NO3-induced leaching of Ca. The mechanism responsible for the decrease in foliar Ca is not known. Our results, however, clearly demonstrate that increased N deposition at sites with low base saturation may affect Ca nutrition even when clear signs of N saturation are not observed.

  2. Daily Activity Patterns and Perch Height Utilization in Pre-Breeding Season by Forest Calotes, Calotes rouxii (Sauria: Agamidae in the Sacred Grove of the Northern Western Ghats

    Directory of Open Access Journals (Sweden)

    Sameer Bajru

    2016-01-01

    Full Text Available Although, the Forest Calotes Calotes rouxii is the most common and endemic species of lizard inhabiting the Western Ghats, information on its ecology is remain scarce. In order to better understanding of life history of C. rouxii, we investigated its pre breeding activity patterns and microhabitat utilization in a small sacred grove (~0.65 ha of the northern Western Ghats. Calotes rouxii showed a unimodal activity pattern, peak activity period was observed at late morning (11.00-12.30 h and afternoon (13.00-15.45 h. The activity patterns of lizards involved basking and resting at early morning period. Once they attained optimum body temperature at peak period activities such as moving, social displays and foraging were performed. In late afternoon all activities were decreased and they retreat to their refuge sites. Sex specific microhabitat segregation was detected; males occupied higher perches than females. The males encounter during study period were positively correlated with temperature while negatively correlated with humidity, however females encountered were not correlated with humidity and temperature.

  3. A Cultural Resources Survey of the Whitlow Ranch Dam and Reservoir Area, Eastern Pinal County, Arizona,

    Science.gov (United States)

    1986-01-01

    actually common in areas on the periphery of the Hohokam world; they occur in the Altar drainage of northern Mexico and the Papagueria (Stacey 1974...The excavation of Los Muertos and neighboring ruins in the Salt River Valley, Southern Arizona. Papers of the Peabody Museum of American Archaeology

  4. A reconnaissance of small mammal communities in Garland and Government prairies, Arizona

    Science.gov (United States)

    Joseph L. Ganey; Carol L. Chambers

    2011-01-01

    Small mammals play key ecological roles in grassland ecosystems, yet little is known regarding small mammal communities in large (>50 km2), high-elevation prairies embedded in ponderosa pine (Pinus ponderosa) forests in north central Arizona. To provide information on community composition and habitat relationships, we live-trapped small mammals on 6 transects in 2...

  5. Phylogeography in the northern Andes: complex history and cryptic diversity in a cloud forest frog, Pristimantis w-nigrum (Craugastoridae).

    Science.gov (United States)

    Kieswetter, Charles M; Schneider, Christopher J

    2013-12-01

    We investigated the pattern of genetic and morphological variation and the timing of diversification in a Neotropical direct developing frog, Pristimantis w-nigrum (Craugastoridae) to gain insight into the historical biogeography of the northern Andes. Phylogenetic inference and analyses of genetic differentiation at mitochondrial and nuclear markers reveal eight mitochondrial clades that display concordant and highly structured nuclear genetic variation along both eastern and western slopes of the Ecuadorian Andes. These eight phylogroups are deeply divergent and show little evidence of change in effective size over substantial periods of time. Consistent with other phylogenetic studies of vertebrates in the Andes, the timing of genetic divergence among lineages coincides with sequential bouts of Andean orogenesis during the late Miocene and early Pliocene. Morphometric analyses recover little morphological variation among populations in spite of considerable genetic divergence. The deep genetic differentiation among populations of P. w-nigrum suggests that this species harbors unrecognized diversity and may represent a complex of cryptic species. These results illuminate the evolutionary processes that generate diversity in tropical montane biomes and underscore the fact that cryptic diversity may be an important component of Neotropical montane biodiversity.

  6. Fire and the production of Astraeus odoratus (Basidiomycetes sporocarps in deciduous dipterocarp-oak forests of northern Thailand

    Directory of Open Access Journals (Sweden)

    Keegan H. Kennedy

    2012-12-01

    Full Text Available The genus Astraeus (Diplocystidiaceae forms ectomycorrhizal associations with many tree species and is a common gasteromycete in tropical and temperate ecosystems worldwide. In Thailand, Astraeus is most prevalent in deciduous dipterocarp-oak forest (DOF in the north and north-east and its ecology is uniquely associated with fire. Rural villagers often burn the seasonally dry DOF ground vegetation causing significant environmental disturbance to promote the growth of Astraeus sporocraps—a local culinary delicacy and important source of household income. The purpose of this work is to investigate whether the practice of burning DOF stimulates the production of Astraeus sporocarps in DOF. Burned and unburned Astraeus habitat was surveyed over two years at two sites in Chiang Mai province and one site in Mae Hong Son province. Changes in soil fungi after a fire as well as vascular vegetation growing with Astraeus were studied. All sporocarps collected were identified as Astraeus odoratus. Astraeus sporocarps were found in both burned and unburned areas in 2010. In 2011, an unusually wet year, no sporocarps were found in burned or unburned areas. The top 2 cm of soil experienced high temperatures which killed fungi, but lower depths were well insulated from the heat. A wide range of vascular flora grew in Astraeus habitat, the most common tree species being Dipterocarpus tuberculatus var. tuberculatus and Dipterocarpus obtusifolius var. obtusifolius. This study shows that Astraeus can produce sporocarps without fire and future work can focus on more environmentally benign methods of harvesting this popular mushroom.

  7. Soil nitrogen affects phosphorus recycling: foliar resorption and plant-soil feedbacks in a northern hardwood forest.

    Science.gov (United States)

    See, Craig R; Yanai, Ruth D; Fisk, Melany C; Vadeboncoeur, Matthew A; Quintero, Brauuo A; Fahey, Timothy J

    2015-09-01

    Previous studies have attempted to link foliar resorption of nitrogen and phosphorus to their. respective availabilities in soil, with mixed results. Based on resource optimization theory, we hypothesized that the foliar resorption of one element could be driven by the availability of another element. We tested various measures of soil N and P as predictors of N and P resorption in six tree species in 18 plots across six stands at the Bartlett Experimental Forest, New Hampshire, USA. Phosphorus resorption efficiency (P resorption also increased with soil P content, which is difficult to explain basdd on single-element limitation, butfollows from the correlation between soil N and soil P. The expected single-element relationships were evident only in the 0 horizon: P resorption was high where resin-available P was low in the Oe (P resorption was high where potential N mineralization in the Oa was low (P resorption. The striking effect of soil N content on foliar P resorption is the first evidence of multiple-element control on nutrient resorption to be reported from an unmanipulated ecosystem.

  8. Quantitative Estimation of Soil Carbon Sequestration in Three Land Use Types (Orchard, Paddy Rice and Forest in a Part of Ramsar Lands, Northern Iran

    Directory of Open Access Journals (Sweden)

    zakieh pahlavan yali

    2017-02-01

    Full Text Available Introduction: The increasing Greenhouse Gases in atmosphere is the main cause of climate and ecosystems changes. The most important greenhouse gas is CO2 that causes global warming or the greenhouse effect. One of the known solutions that reduces atmospheric carbon and helps to improve the situation, is carbon sequestration in vegetation cover and soil. Carbon sequestration refers to the change in atmospheric CO2 into organic carbon compounds by plants and capture it for a certain time . However, the ecosystems with different vegetation have Impressive Influence on soil carbon sequestration (SCS. Soil as the main component of these ecosystems is a world-wide indicator which has been known to play an important role in global balance of carbon sequestration. Furthermore, carbon sequestration can be a standard world trade and becomes guaranteed. Costs of transfer of CO2 (carbon transfer From the atmosphere into the soil based on the negative effects of increased CO2 on Weather is always increasing, This issue can be faced by developing countries to create a new industry, especially when conservation and restoration of rangeland to follow. This research was regarded due to estimation of SCS in three land use types (orchard, paddy rice and forest in a Part of Ramsar Lands, Northern Iran. Materials and Methods: Ramsar city with an area of about 729/7 km2 is located in the western part of Mazandaran province. Its height above sea level is 20 meters. Ramsar city is situated in a temperate and humid climate. Land area covered by forest, orchard and paddy rice. After field inspection of the area, detailed topographic maps of the specified zone on the study were also tested. In each of the three land types, 500 hectares in the every growing and totally 1,500 hectares as study area were selected .For evaluation the sequestration of carbon in different vegetation systems,15 soil profile selected and sampling from depth of 0 to 100 centimetres of each profile

  9. Application of Ca stable isotopes to long-term changes in the Ca cycle of a Northern Hardwood forest

    Science.gov (United States)

    Kurtz, A. C.; Takagi, K.; Bailey, S. W.; Bullen, T. D.

    2015-12-01

    The Hubbard Brook Ecosystem Study (New Hampshire, USA) presents an unusual opportunity for the application of innovative isotope methods in forest biogeochemistry. Changes in biogeochemical cycling resulting from decades of acid deposition, subsequent reductions in acid deposition, and a series of experimental treatments (harvesting, Ca amendment) have been studied continuously for 60 years at this site. Importantly, researchers have archived soil, water, and vegetation samples for much of the site's history. Our work seeks to complement earlier mass balance studies of Ca cycling by measuring Ca isotope ratios on archived samples. In the first component of our study, we examined the Ca isotopic response to an experimental clearcut in the early 1980's. Earlier work showed that the clearcut promoted dramatic loss of Ca from the watershed, indicated by a 5-fold increase in streamwater Ca concentrations. The mechanism for this loss was unclear as no resolvable changes in soil Ca pools were observed. Our work shows that streamwater dissolved Ca becomes isotopically lighter as Ca concentrations increase. These data are best accounted for by an increase in Ca loss from the soil cation exchange complex. Soil exchangeable δ44Ca itself evolves towards lighter values in the years following the experimental harvest. We interpret this as replenishment of the soil exchange complex by release of isotopically light Ca from root biomass. In the second component of our study, we examine decadal-scale changes in streamwater and soil Ca in an un-manipulated biogeochemical reference watershed. Historical data from Hubbard Brook show that streamwater Ca concentrations began decreasing sharply in the early 1970's, attributed to decreased deposition of both acidity and Ca with the passage of the Clean Air Act. Preliminary data indicate no resolvable change in the average δ44Ca of streamwater, with variability mostly attributable to discharge (flowpath control). Preliminary data

  10. Snowpack-atmosphere gas exchanges of carbon dioxide, ozone, and nitrogen oxides at a hardwood forest site in northern Michigan

    Directory of Open Access Journals (Sweden)

    Brian Seok

    2015-03-01

    Full Text Available Abstract Snowpack-atmosphere gas exchanges of CO2, O3, and NOx (NO + NO2 were investigated at the University of Michigan Biological Station (UMBS, a mid-latitude, low elevation hardwood forest site, during the 2007–2008 winter season. An automated trace gas sampling system was used to determine trace gas concentrations in the snowpack at multiple depths continuously throughout the snow-covered period from two adjacent plots. One natural plot and one with the soil covered by a Tedlar sheet were setup for investigating whether the primary source of measured trace gases was biogenic (i.e., from the soil or non-biogenic (i.e., from the snowpack. The results were compared with the “White on Green” study conducted at the Niwot Ridge (NWT Long Term Ecological Research site in Colorado. The average winter CO2 flux ± s.e. from the soil at UMBS was 0.54 ± 0.037 µmol m-2 s-1 using the gradient diffusion method and 0.71 ± 0.012 µmol m-2 s-1 using the eddy covariance method, and in a similar range as found for NWT. Observed snowpack-O3 exchange was also similar to NWT. However, nitrogen oxides (NOx fluxes from snow at UMBS were 10 times smaller than those at NWT, and fluxes were bi-directional with the direction of the flux dependent on NOx concentrations in ambient air. The compensation point for the change in the direction of NOx flux was estimated to be 0.92 nmol mol-1. NOx in snow also showed diurnal dependency on incident radiation. These NOx dynamics in the snow at UMBS were notably different compared to NWT, and primarily determined by snow-atmosphere interactions rather than by soil NOx emissions.

  11. Arizona TeleMedicine Project.

    Science.gov (United States)

    Arizona Univ., Tucson. Coll. of Medicine.

    Designed to provide health services for American Indians living on rurally isolated reservations, the Arizona TeleMedicine Project proposes to link Phoenix and Tucson medical centers, via a statewide telecommunications system, with the Hopi, San Carlos Apache, Papago, Navajo, and White Mountain Apache reservations. Advisory boards are being…

  12. Boots on the Ground: Arizona

    Centers for Disease Control (CDC) Podcasts

    2013-12-26

    In this podcast, we talk to CDC public health advisor Lisa Speissegger about her response efforts during the 2013 Arizona wildfires.  Created: 12/26/2013 by Office of Public Health Preparedness and Response (PHPR).   Date Released: 12/26/2013.

  13. A Melioidosis Case in Arizona

    Centers for Disease Control (CDC) Podcasts

    2011-10-03

    David Blaney, Medical Officer, Bacterial Special Pathogens Branch, discusses an unusual melioidosis case in Arizona.  Created: 10/3/2011 by National Center for Emerging Zoonotic and Infectious Diseases (NCEZID).   Date Released: 10/5/2011.

  14. Canopy-scale flux measurements and bottom-up emission estimates of volatile organic compounds from a mixed oak and hornbeam forest in northern Italy

    Science.gov (United States)

    Acton, W. Joe F.; Schallhart, Simon; Langford, Ben; Valach, Amy; Rantala, Pekka; Fares, Silvano; Carriero, Giulia; Tillmann, Ralf; Tomlinson, Sam J.; Dragosits, Ulrike; Gianelle, Damiano; Hewitt, C. Nicholas; Nemitz, Eiko

    2016-06-01

    This paper reports the fluxes and mixing ratios of biogenically emitted volatile organic compounds (BVOCs) 4 m above a mixed oak and hornbeam forest in northern Italy. Fluxes of methanol, acetaldehyde, isoprene, methyl vinyl ketone + methacrolein, methyl ethyl ketone and monoterpenes were obtained using both a proton-transfer-reaction mass spectrometer (PTR-MS) and a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS) together with the methods of virtual disjunct eddy covariance (using PTR-MS) and eddy covariance (using PTR-ToF-MS). Isoprene was the dominant emitted compound with a mean daytime flux of 1.9 mg m-2 h-1. Mixing ratios, recorded 4 m above the canopy, were dominated by methanol with a mean value of 6.2 ppbv over the 28-day measurement period. Comparison of isoprene fluxes calculated using the PTR-MS and PTR-ToF-MS showed very good agreement while comparison of the monoterpene fluxes suggested a slight over estimation of the flux by the PTR-MS. A basal isoprene emission rate for the forest of 1.7 mg m-2 h-1 was calculated using the Model of Emissions of Gases and Aerosols from Nature (MEGAN) isoprene emission algorithms (Guenther et al., 2006). A detailed tree-species distribution map for the site enabled the leaf-level emission of isoprene and monoterpenes recorded using gas-chromatography mass spectrometry (GC-MS) to be scaled up to produce a bottom-up canopy-scale flux. This was compared with the top-down canopy-scale flux obtained by measurements. For monoterpenes, the two estimates were closely correlated and this correlation improved when the plant-species composition in the individual flux footprint was taken into account. However, the bottom-up approach significantly underestimated the isoprene flux, compared with the top-down measurements, suggesting that the leaf-level measurements were not representative of actual emission rates.

  15. Assessment of local management practices on the population ecology of some medicinal plants in the coniferous forest of Northern Parts of Pakistan.

    Science.gov (United States)

    Sher, Hassan; Elyemeni, Mohammad; Khan, Abdur Rehman; Sabir, Amjad

    2011-04-01

    A study on the assessment of local management practices on the population of three medicinal plants viz.: Persicaria amplexicaule. D. Don., Valeriana jatamansi Jones and Viola serpens Wall ex Roxb was conducted during 2002-2004 in the coniferous forest of Northern Parts of Pakistan. The objective of the study was to know the impact of current management practices on the population size of targeted plants. The study showed that the involvement of locals in the gathering of targeted plants varied with the change in elevation. Among the targeted plants V. serpens was collected by large majorities of people (83.3%) at 2700 m followed by 72% at 2300 m and 37% at 1900 m. V. jatamansi was harvested by a small number of people (18.1%) at 1900 and 2300 m each, followed by 8.3% at 2700 m. While P. amplexicaule was harvested by a few collectors (9.1%) at 1900 m and 9.6% at 2300 m followed by 8.3% at 2700 m. The study concluded that these species have been extracted so heavily in the past that they are found now sparsely in some sites of the study area. Secondly, due to loss of its habitat by deforestation and encroachment of land for cultivation its population is on the decline towards extinction. Therefore, the current study recommends the conservation of the remaining populations of targeted plants through active participation of local communities.

  16. [Temperature sensitivity of soil organic carbon mineralization and β-glucosidase enzymekinetics in the northern temperate forests at different altitudes, China].

    Science.gov (United States)

    Fan, Jin-juan; Li, Dan-dan; Zhang, Xin-yu; He, Nian-peng; Bu, Jin-feng; Wang, Qing; Sun, Xiao-min; Wen, Xue-fa

    2016-01-01

    Soil samples, which were collected from three typical forests, i.e., Betula ermanii forest, coniferous mixed broad-leaved forest, and Pinus koraiensis forest, at different altitudes along the southern slope of Laotuding Mountain of Changbai Mountain range in Liaoning Province of China, were incubated over a temperature gradient in laboratory. Soil organic carbon mineralization rates (Cmin), soil β-1,4-glucosidase (βG) kinetics and their temperature sensitivity (Q₁₀) were measured. The results showed that both altitude and temperature had significant effects on Cmin · Cmin increased with temperature and was highest in the B. ermanii forest. The temperature sensitivity of Cmin [Q₁₀(Cmin)] ranked in order of B. ermanii forest > P. koraiensis forest > coniferous mixed broad-leaved forest, but did not differ significantly among the three forests. Both the maximum activity (Vmax) and the Michaelis constant (Km) of the βG responded positively to temperature for all the forests. The temperature sensitivity of Vmax [Q₁₀(Vmax)] ranged from 1.78 to 1.90, and the temperature sensitivity of Km [Q₁₀(Km)] ranged from 1.79 to 2.00. The Q₁₀(Vmax)/Q10(Km) ratios were significantly greater in the B. ermanii soil than in the other two forest soils, suggesting that the βG kinetics-dependent impacts of the global warming or temperature increase on the decomposition of soil organic carbon were temperature sensitive for the forests at the higher altitudes.

  17. SYCAMORE CANYON PRIMITIVE AREA, ARIZONA.

    Science.gov (United States)

    Huff, Lyman C.; Raabe, R.C.

    1984-01-01

    The Sycamore Canyon Primitive Area, which occupies about 74 sq mi, lies about 24 mi southwest of Flagstaff, Arizona. To help evaluate the area for mineral resources, sediment samples were collected along Sycamore Creek and its tributaries. These were analyzed for traces of the ore metals without finding any local concentrations. In addition, a scintillometer was used to test rocks in the area without finding any abnormal radioactivity.

  18. 76 FR 28079 - Notice of Intent To Repatriate Cultural Items: Arizona State Museum, University of Arizona...

    Science.gov (United States)

    2011-05-13

    ... National Park Service Notice of Intent To Repatriate Cultural Items: Arizona State Museum, University of... intent to repatriate cultural items in the possession of the Arizona State Museum, University of Arizona... animal hair, 1 bag of sand, 1 lump of earth, 2 animal tails, 1 bundle of sticks, 2 carved wooden symbols...

  19. 陕北黄龙山林区景观格局动态%Dynamics of Landscape Pattern in Huanglong Mountain Forest Region of Northern Shaanxi Province

    Institute of Scientific and Technical Information of China (English)

    李敏; 赵鹏祥; 郝红科; 杨延征; 袁飞

    2012-01-01

    Based on the forest inventory data of Huanglong Mountain in 1986 , 1997 and 2006, we analyzed the changes of landscape types and landscape structure.The landscape was changed greatly during the 20 years.The area of forested land continuously was increased, while the shrub land and wasteland were gradually decreased.The area of the cultivated land and immature forest land increased from 1986 to 1997, while decreased from 1997 to 2006.Changes in Cupressus forest land and nursery land, which accounted for only a small part of the entire landscape, were not significant.At the landscape level, the area of hard broad-leaved forests and coniferous forests was increased by 40% from 1986 to 2006.The area of Cupressus forest land remained unchanged at approximate 2 000 hm during the two periods, while the area of soft broad-leaved forest land continuously decreased.Moreover, the age-class structure of the major species significantly varied.The hard broad-leaved forests and coniferous forests merged with a block which had the largest patch index and was much greater than that of the other landscape types in each period.The landscape diversity decreased, while the landscape heterogeneity, fragmentation and dominance increased.The patch types tended to distribute in reunion state.

  20. Remote Sensing of Forest Health Indicators for Assessing Change in Forest Health

    Science.gov (United States)

    Michael K. Crosby; Zhaofei Fan; Martin A. Spetich; Theodor D. Leininger

    2012-01-01

    Oak decline poses a substantial threat to forest health in the Ozark Highlands of northern Arkansas and southern Missouri, where coupled with diseases and insect infestations, it has damaged large tracts of forest lands. Forest Health Monitoring (FHM) crown health indicators (e.g. crown dieback, etc.), collected by the U.S. Forest Service’s Forest Inventory and...

  1. Analysis on life forms of lichens in forest ecosystem of Northern Xinjiang%新疆北部森林生态系统地衣植物生活型分析

    Institute of Scientific and Technical Information of China (English)

    孜比尔尼沙·吾买尔; 艾尼瓦尔·吐米尔; 阿不都拉·阿巴斯

    2003-01-01

    Life forms of lichen of forest ecosystem in Northern Xinjiang were researched in the Kanas National Natural Reservation Area.They have been grouped into 6 types:Epipetria,Soil-epipetria,Epiphytia arboricosa,Epiphytia moss,Epiphytis grass and Dry-radicantia,in which the species of Epiphytia arboricosa account for 36.89% of the total species in this area,the species of Epipetria for 22.33% and Epiphytia grass the least.The results show that life forms of lichem at the srea in Northem Xinjiang are relatively rich,which indicates the biodiversity characteristics of lichen.

  2. Effect of tree thinning and litter removal on the radiocesium (Cs-134, 137) discharge rates in the Kawauchi forest plantation (Fukushima Prefecture, northern Japan)

    Science.gov (United States)

    López-Vicente, Manuel; Onda, Yuichi; Takahashi, Junko; Kato, Hiroaki; Hisadome, Keigo

    2016-04-01

    On 11 March 2011 a 9.0 earthquake and the resulting tsunami occurred in central-eastern Japan triggering, one day after, the Fukushima Dai-ichi nuclear power plant (DNPP) accident. Despite the bulk of radionuclides (ca. 80%) were transported offshore and out over the Pacific Ocean, significant wet and dry deposits of those radionuclides occurred mainly in the Fukushima Prefecture and in a minor way in the Miyagi, Tochigi, Gunma and Ibaraki Prefectures. As a consequence and among other radionuclides, a total of 511,000 TBq of I-131, 13,500 TBq of Cs-134 and 13,600 TBq of Cs-137 were released into the atmosphere and the ocean, contaminating cultivated soils, rivers, settlements and forested areas. This accident caused severe environmental and economic damages. Several decontamination practices have done, including tree thinning and litter removal within the forests and tree plantations. In this study we analysed the effect of eight different management practices on the radiocesium (Cs-134 and Cs-137) discharge rates during 20 months (May'2013 - Dec'2014) in a Japanese cedar (Cryptomeria japonica) plantation (stand age of 57 years), located in a hillslope near the Kawauchi village, Fukushima Prefecture, northern Japan. This study area (37⁰ 20' 04" N, 140⁰ 53' 13.5" E) is located 16 km southwestern from the DNPP and within the evacuation area. The soils are Andosols. Ten runoff plots (5 x 2 meters) were installed and measurements started on May 2013. Two plots remained without any treatment as control plots and the other eight plots represented the following management practices: Mng1) Litter removal + clear-cutting (no sheet); Mng2) Litter removal + clear-cutting (no sheet); Mng3) Litter removal + clear-cutting (no sheet); Mng4) Litter removal; Mng5) Thinning (logged area); Mng6) Thinning (under remnant trees); Mng7) Litter removal + thinning (logged area); Mng8) Litter removal + thinning (under remnant trees). Each plot had a gauging station and sediment samples

  3. Hygroscopic properties of newly formed ultrafine particles at an urban site surrounded by deciduous forest (Sapporo, northern Japan) during the summer of 2011

    Science.gov (United States)

    Jung, J.; Kawamura, K.

    2014-07-01

    To investigate the hygroscopic properties of ultrafine particles during new particle formation events, the hygroscopic growth factors of size-segregated atmospheric particles were measured at an urban site in Sapporo, northern Japan, during the summer of 2011. The hygroscopic growth factor at 85 % relative humidity [g(85%)] of freshly formed nucleation mode particles was 1.11 to 1.28 (average: 1.16 ± 0.06) at a dry particle diameter (Dp) centered on 20 nm, which is equivalent to 1.17 to 1.35 (1.23 ± 0.06) at a dry Dp centered on 100 nm after considering the Kelvin effect. These values are comparable with those of secondary organic aerosols, suggesting that low-volatility organic vapors are important to the burst of nucleation mode particles. The equivalent g(85%) at a dry Dp of 100 nm for nucleated particles that have grown to Aitken mode sizes (1.24 to 1.34; average: 1.30 ± 0.04) were slightly higher than those of newly formed nucleation mode particles, suggesting that the growth of freshly formed nucleation mode particles to the Aitken mode size can be subjected to condensation of not only low-volatility organic vapors, but also water-soluble inorganic species. Based on this result, and previous measurement of radiocarbon in aerosols, we suggest that the burst of nucleation mode particles and their subsequent growth were highly affected by biogenic organic emissions at this measurement site, which is surrounded by deciduous forest. Gradual increases in mode diameter after the burst of nucleation mode particles were observed under southerly wind conditions, with a dominant contribution of intermediately hygroscopic particles. However, sharp increases in mode diameter were observed when the wind direction shifted to northwesterly or northeasterly, with a sharp increase in the highly hygroscopic particle fraction of the Aitken mode particles, indicating that the hygroscopic growth factor of newly formed particles is perturbed by the local winds that deliver

  4. Effects of a clearcut on the net rates of nitrification and N mineralization in a northern hardwood forest, Catskill Mountains, New York, USA

    Science.gov (United States)

    Burns, Douglas A.; Murdoch, Peter S.

    2005-01-01

    The Catskill Mountains of southeastern New York receive among the highest rates of atmospheric nitrogen (N) deposition in eastern North America, and ecosystems in the region may be sensitive to human disturbances that affect the N cycle. We studied the effects of a clearcut in a northern hardwood forest within a 24-ha Catskill watershed on the net rates of N mineralization and nitrification in soil plots during 6 years (1994-1999) that encompassed 3-year pre- and post-harvesting periods. Despite stream NO3- concentrations that increased by more than 1400 ??mol l-1 within 5 months after the clearcut, and three measures of NO3- availability in soil that increased 6- to 8-fold during the 1st year after harvest, the net rates of N mineralization and nitrification as measured by in situ incubation in the soil remained unchanged. The net N-mineralization rate in O-horizon soil was 1- 2 mg N kg-1 day-1 and the net nitrification rate was about 1 mg N kg-1 day-1, and rates in B-horizon soil were only one-fifth to one-tenth those of the O-horizon. These rates were obtained in single 625 m2 plots in the clearcut watershed and reference area, and were confirmed by rate measurements at 6 plots in 1999 that showed little difference in N-mineralization and nitrification rates between the treatment and reference areas. Soil temperature increased 1 ?? 0.8??C in a clearcut study plot relative to a reference plot during the post-harvest period, and soil moisture in the clearcut plot was indistinguishable from that in the reference plot. These results are contrary to the initial hypothesis that the clearcut would cause net rates of these N-cycling processes to increase sharply. The in situ incubation method used in this study isolated the samples from ambient roots and thereby prevented plant N uptake; therefore, the increases in stream NO3- concentrations and export following harvest largely reflect diminished uptake. Changes in temperature and moisture after the clearcut were

  5. Debris Flows and Road Damage Following a Wildfire in 2014 on the Klamath National Forest, Northern California, Near the Community of Seiad, CA

    Science.gov (United States)

    De La Fuente, J. A.; Mikulovsky, R. P.

    2016-12-01

    Wildfires in summer 2014 burned more than 200,000 acres on the Klamath National Forest in Northern California, east of Seiad, CA. Much of the area burned at high and moderate severity, and is underlain by Slinkard Pluton granitic rock. During winter 2014-2015, there were a few debris flows in small streams, and some clogged culverts on the road system, but overall road damage was minor. In July of 2015, a strong convective storm triggered several large debris flows, including East Fork Walker and No Name Creeks. These and other debris flows damaged road stream crossings, and delivered a large volume of sediment to the stream network. LiDAR differencing is being used to identify and quantify erosion and deposition from that storm. Field inventories revealed widespread rills and small gullies on steep, burned hillslopes, particularly where underlain by granitic rock. Resulting debris flows were of the sediment bulking variety, and no landslide-triggered debris flows were observed. This may be because intense summer storms are of short duration, and are unlikely to saturate the surface mantle, due also to water repellant soil conditions. It is unknown if erosion during the first winter affected the response to the July storm. Storms around January 17, 2016 initiated many road fill failures, and most were limited to the outer half of the road. Field investigations revealed that granitic road fills failed in a variety of settings, including planar hillslopes, on the flanks of ridges, channel crossings, and at road dips. In virtually all cases, vegetation on the fills, up to 50 years old, had been killed by the 2014 fire. Some fills developed small cracks and scarps, whereas others failed catastrophically as debris slides/flows. Few sediment-bulking debris flows were observed in January, 2016. Road damage exceeded two million dollars, and qualified for Emergency Relief Federally Owned funding (ERFO). The effects of the July, 2015 storm were dominated by sheet wash

  6. Rhode Island's Forest Resources, 2006

    Science.gov (United States)

    Brett J. Butler; I. Ted Goodnight; Barbara O' Connell; Bruce Payton; Bryan Tirrell

    2008-01-01

    Table 1 and Figures 2 and 3 have been revised by the authors and these revisions were incorporated into the publication on May 27, 2008. This publication provides an overview of forest resource attributes for Rhode Island based on an annual inventory conducted by the Forest Inventory and Analysis program at the Northern Research Station of the U.S. Forest Service....

  7. 21 CFR 866.3035 - Arizona spp. serological reagents.

    Science.gov (United States)

    2010-04-01

    .... The identification aids in the diagnosis of disease caused by bacteria belonging to the genus Arizona and provides epidemiological information on diseases caused by these microorganisms. Arizona spp....

  8. Comparative use of riparian corridors and oases by migrating birds in southeast Arizona

    Science.gov (United States)

    Skagen, S.K.; Melcher, C.P.; Howe, W.H.; Knopf, F.L.

    1998-01-01

    The relative importance of cottonwood-willow riparian corridors and isolated oases to land birds migrating across southeastern Arizona was evaluated during four spring migrations, 1989 to 1994, based on patterns of species richness, relative abundance, density, and body condition of birds. We surveyed birds in 13 study sites ranging in size and connectivity from small isolated patches to extensive riparian forest, sampled vegetation and insects, and captured birds in mistnets. The continuous band of riparian vegetation along the San Pedro River does not appear to be functioning as a corridor for many migrating species, although it may for a few, namely Yellow-breasted Chats (Icteria virens), Summer Tanagers (Piranga rubra), and Northern Rough-winged Swallows (Steldigopteryx serripennis), which account for fewer than 10% of the individuals migrating through the area. Small, isolated oases hosted more avian species than the corridor sites, and the relative abundances of most migrating birds did not differ between sites relative to size-connectivity. There were few differences in between-year variability in the relative abundances of migrating birds between corridor and oasis sites. Between-year variability decreased with overall abundance of species and was greater for species with breeding ranges that centered north of 50??N latitude. Body condition of birds did not differ relative to the size-connectivity of the capture site, but individuals of species with more northerly breeding ranges had more body fat than species that breed nearby. Peak migration densities of several bird species far exceeded breeding densities reported for the San Pedro River, suggesting that large components of these species were en route migrants. Peak densities of Yellow Warblers (Dendroica petechia) reached 48.0 birds/ha, of Wilson's Warblers (Wilsonia pusilla) 33.7 birds/ha, and of Yellow-rumped Warblers (D. coronata) 30.1 birds/ha. Riparian vegetation is limited in extent in the

  9. Land grants and the U.S. Forest Service

    Science.gov (United States)

    Carol Raish; Alice M. McSweeney

    2008-01-01

    The U.S. Forest Service (Forest Service) has a long, shared history with the land grants of northern New Mexico. During the land grant adjudication process after U.S. conquest, much common land from both Spanish and Mexican land grants was declared public domain, eventually becoming part of the northern and central New Mexico National Forests. These forests were...

  10. Arizona: In Search of the Displaced Homemaker.

    Science.gov (United States)

    Woods, Doris

    The model described offers information about displaced homemakers that, while specific to Arizona, can provide a guide to persons in any state responsible for program planning. The report presents results of an Arizona Department of Education study which was conducted to: (1) identify the "displaced homemaker;" (2) define the need for services;…

  11. 78 FR 57923 - Arizona Disaster #AZ-00029

    Science.gov (United States)

    2013-09-20

    ... ADMINISTRATION Arizona Disaster AZ-00029 AGENCY: Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the State of Arizona dated 09/13/2013. Incident: Yarnell Hill Fire. Incident Period: 06/28/2013 through 07/10/2013. Effective Date:...

  12. 76 FR 42156 - Arizona Disaster #AZ-00016

    Science.gov (United States)

    2011-07-18

    ... ADMINISTRATION Arizona Disaster AZ-00016 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the State of Arizona dated 07/11/2011. Incident: Monument Fire. Incident Period: 06/12/2011 and continuing. Effective Date:...

  13. 76 FR 45644 - Arizona Disaster #AZ-00016

    Science.gov (United States)

    2011-07-29

    ... is hereby amended to modify the incident description for this disaster from Monument Fire to Monument... ADMINISTRATION Arizona Disaster AZ-00016 AGENCY: U.S. Small Business Administration. ACTION: Amendment 1. SUMMARY: This is an amendment of the Administrative declaration of disaster for the State of Arizona dated...

  14. Developing a monitoring program for bird populations in the Chiricahua Mountains, Arizona, using citizen observers: Initial stages

    Science.gov (United States)

    Joseph L Ganey; Jose M. Iniguez; Jamie S. Sanderlin; William M. Block

    2017-01-01

    The Madrean Sky Island region is an ecologically important area harboring exceptional biodiversity, including a unique avifauna that supports a thriving ecotourism industry in southeastern Arizona. This area has been impacted by several large wildfires in recent decades. These wildfires have altered vegetation composition and structure in forests and woodlands, and the...

  15. Leaf area index is the principal scaling parameter for both gross photosynthesis and ecosystem respiration of Northern deciduous and coniferous forests

    Science.gov (United States)

    Lindroth, Anders; Lagergren, Fredrik; Aurela, Mika; Bjarnadottir, Brynhildur; Christensen, Torben; Dellwik, Ebba; Grelle, Achim; Ibrom, Andreas; Johansson, Torbjörn; Lankreijer, Harry; Launiainen, Samuli; Laurila, Tuomas; Mölder, Meelis; Nikinmaa, Eero; Pilegaard, Kim; Sigurdsson, Bjarni D.; Vesala, Timo

    2008-04-01

    Data on net CO2 exchange from eight forests in Denmark, Sweden, Finland and Iceland were used to analyse which factors were controlling photosynthesis and respiration. The forests consisted of different species ranging in climatic condition from temperate to subarctic. Only well mixed conditions were analysed (u* > 0.3 m s-1). The parameters of a light response function showed strong seasonal variations with similar behaviour for all stands except for a beech forest where the development of a vigorous ground vegetation in spring affected the photosynthesis parameters differently as compared to the other forests. The beech forest also showed the highest respiration rates in the earlier part of the growing season in contrast to the other forests that showed maximum values in late part of July. The mean half-monthly nighttime respiration rates were well explained by an equation with one fitting parameter, the respiration rate at 10 °C, with an r2 = 0.864 for all stands together. The difference between the stands concerning both photosynthesis and respiration parameters were largely explained by the differences in LAI. After normalizing for LAI, the only remaining correlation was between respiration and stand age. These results are promising for application of remote sensing for estimation of respiration as well as gross primary productivity from forests.

  16. Potential of the Russian forests and forest industries

    Energy Technology Data Exchange (ETDEWEB)

    Anttonen, T.; Petrov, A.P. [eds.

    1997-12-31

    The publication contains the proceedings of the seminar `Potential of the Russian Forests and Forest Industries` held in Moscow, May 14-16, 1997. The seminar was one step along the road to spread knowledge and become acquainted with forestry and forest industries in northern Europe and Russia. The seminar proceedings contain a lot of fresh information concerning forestry and forest industries in Russia. Both have undergone many changes and reforms during the last few years

  17. Installation Restoration Program. Phase II, Stage 1. Problem Confirmation Study, Luke Air Force Base, Glendale, Arizona.

    Science.gov (United States)

    1984-11-01

    potable water in LAFB. Surface water from the Central Arizona Project (CAP) is available to the Base, but at a significantly higher cost than that of...available supplies of potable water which currently support the Base mission at LAFB. 1-16 1-16 SECTION 2 ENVIRONMENTAL SETTING 2.1 REGIONAL GEOLOGY Luke Air...the northern portion of the Base discharges toward the nearest natural surface water feature, the Agua Fria River. Figure 2-1 summarizes surface

  18. Trends in Snag Populations in Drought-Stressed Mixed-Conifer and Ponderosa Pine Forests (1997–2007

    Directory of Open Access Journals (Sweden)

    Joseph L. Ganey

    2012-01-01

    Full Text Available Snags provide important biological legacies, resources for numerous species of native wildlife, and contribute to decay dynamics and ecological processes in forested ecosystems. We monitored trends in snag populations from 1997 to 2007 in drought-stressed mixed-conifer and ponderosa pine (Pinus ponderosa Dougl. ex Laws forests, northern Arizona. Median snag density increased by 75 and 90% in mixed-conifer and ponderosa pine forests, respectively, over this time period. Increased snag density was driven primarily by a large pulse in drought-mediated tree mortality from 2002 to 2007, following a smaller pulse from 1997 to 2002. Decay-class composition and size-class composition of snag populations changed in both forest types, and species composition changed in mixed-conifer forest. Increases in snag abundance may benefit some species of native wildlife in the short-term by providing increased foraging and nesting resources, but these increases may be unsustainable in the long term. Observed changes in snag recruitment and fall rates during the study illustrate the difficulty involved in modeling dynamics of those populations in an era of climate change and changing land management practices.

  19. Palynological evidence of the replacement of the hygrophilous forest by field vegetation during the last 7,000 years B.P. in the northern coast of Rio de Janeiro, Brazil.

    Science.gov (United States)

    Luz, Cynthia F P da; Barth, Ortrud M; Martin, Louis; Silva, Cleverson G; Turcq, Bruno J

    2011-09-01

    Historians claim that European colonizers of the northern coast of Rio de Janeiro State found vast herbaceous fields when arrived in this region. Hypotheses about the origin of these fields include forest burning by the Goitacás indians and periodical floods by the Paraíba do Sul River and the lagoon system. The palynologycal analysis of two lake cores obtained in the municipality of Campos dos Goytacazes revealed opening episodes of hygrophilous forest and the establishment of field vegetation, recorded at ca. 6,500 and ca. 4,000 (14)C yr BP. The partial replacement of forest by field vegetation in the first episode was probably caused by floods of the lower areas during the development of the Holocene lagoon phase. During the second episode, successions of vegetational patterns occurred due to lowering of the sea level. Drying and enlarging of the coastal plain have allowed its colonization by herbs and heliophyte plants. The palynological analysis does not provide any evidence that sustains the theories of use of fire and agricultural activities by indigenous groups during these periods.

  20. Managing for Climate Change Adaptation in Forests: a Case Study from the U.S. Southwest

    Science.gov (United States)

    Kerhoulas, L. P.; Kolb, T.; Koch, G. W.; Hurteau, M. D.

    2016-12-01

    Forest mortality related to climate change is an increasingly common global phenomenon. We provide a case study of the U.S. Southwest to investigate the interactions among forest restoration treatments that alter stand density, tree growth, and drought resistance in trees of different size classes. Using cores taken from five positions in large trees (coarse roots, breast height, base of live crown, mid-crown branch, and treetop) and breast height in small trees, we investigated how radial growth response to thinning and precipitation availability varied in 72 ponderosa pines Pinus ponderosa Dougl. in northern Arizona. Ten years after thinning, growth of small trees did not respond significantly to thinning whereas growth of large trees increased following moderate and heaving thinning, and this response was similar across within-tree core sample positions. The intensity of thinning treatment did not significantly affect dry-year growth in small trees. In large trees, dry-year growth after thinning was maintained at pre-thinning levels in moderate and heavy thinning treatments but decreased in the light thinning and control treatments. Our findings indicate that more aggressive thinning treatments used for forest restoration stimulate growth throughout large residual trees from coarse roots to branches and also improve drought resistance, providing a greater resilience to future climate-related stress. These responses to treatment are more pronounced in large trees than small trees. Forest thinning is therefore recommended in systems that are likely to experience increased temperature and decreased precipitation as a result of climate change.

  1. Geothermal resources in Arizona: a bibliography. Circular 23

    Energy Technology Data Exchange (ETDEWEB)

    Calvo, S.S.

    1982-01-01

    This bibliography references all reports and maps generated by the Arizona Bureau of Geology and Mineral Technology and the Arizona Geothermal Commercialization Team of the Department of Chemical Engineering, University of Arizona. To provide a more comprehensive listing of geothermal energy in Arizona, all available geothermal papers from other sources have been included. A total of 224 references are presented. (MHR)

  2. Arizona black rattlesnake (Crotalus viridis cerberus)

    Science.gov (United States)

    Nowak, Erika M.

    2006-01-01

    The Arizona black rattlesnake makes its home at higher elevations in Arizona and far western New Mexico. The snake's use of high-altitude habitat and its black coloration as an adult distinguishes it from other subspecies of the western rattlesnake (Crotalus viridis), which prefer lower elevations and range from tan to reddish in color as adults. These physical and habitat differences are also reflected in genetic differences that suggest that the Arizona black rattlesnake may be a new species of rattlesnake. Despite the species's limited range, basic biological information needed to make management decisions is lacking for most Arizona black rattlesnake populations. To address this need, U.S. Geological Survey (USGS) scientists conducted research on the species in Arizona national park units from 2003 to 2005. The research examined relative population abundance, movement patterns, range requirements, dietary habits, and winter and summer habitat. Research in Arizona national parks was made possible through the support of the Western National Parks Association, Tonto National Monument, and the USGS Science Internships for Workforce Diversity Program. Importantly, the park-based research was used to augment a long-term mark-recapture study of the species that has been conducted by USGS biologists at sites near Flagstaff, Arizona, since 1999. USGS researchers were the first to conduct extensive studies of this species in the wild.

  3. Response of brown-headed cowbirds and three host species to thinning treatments in low-elevation ponderosa pine forests along the northern Colorado Front Range

    Science.gov (United States)

    Keeley, W.H.; Germaine, Stephen S.; Stanley, Thomas R.; Spaulding, Sarah A.; Wanner, C.E.

    2013-01-01

    Thinning ponderosa pine (Pinus ponderosa) forests to achieve desired ecological conditions remains a priority in the North American west. In addition to reducing the risk of high-severity wildfires in unwanted areas, stand thinning may increase wildlife and plant diversity and provide increased opportunity for seedling recruitment. We initiated conservative (i.e. minimal removal of trees) ponderosa stand thinning treatments with the goals of reducing fire risk and improving habitat conditions for native wildlife and flora. We then compared site occupancy of brown-headed cowbirds (Molothrus ater), chipping sparrows (Spizella passerina), plumbeous vireos (Vireo plumbeus), and western wood-pewees (Contopus sordidulus) in thinned and unthinned (i.e., control) forest stands from 2007 to 2009. Survey stations located in thinned stands had 64% fewer trees/ha, 25% less canopy cover, and 23% less basal area than stations in control stands. Occupancy by all three host species was negatively associated with tree density, suggesting that these species respond favorably to forest thinning treatments in ponderosa pine forests. We also encountered plumbeous vireos more frequently in plots closer to an ecotonal (forest/grassland) edge, an association that may increase their susceptibility to edge-specialist, brood parasites like brown-headed cowbirds. Occupancy of brown-headed cowbirds was not related to forest metrics but was related to occupancy by plumbeous vireos and the other host species in aggregate, supporting previous reports on the affiliation between these species. Forest management practices that promote heterogeneity in forest stand structure may benefit songbird populations in our area, but these treatments may also confer costs associated with increased cowbird occupancy. Further research is required to understand more on the complex relationships between occupancy of cowbirds and host species, and between cowbird occupancy and realized rates of nest parasitism.

  4. A methodology for analysing temporal changes of forest surface using aerial photos for the application of Kyoto protocol: a study case in Northern Italy

    Directory of Open Access Journals (Sweden)

    Salvadori I

    2006-01-01

    Full Text Available According to art. 3.3 of the Kyoto Protocol, Italy, like other Parties included in Annex I, shall report the net changes in greenhouse gas emissions by sources and removals by sinks resulting from afforestation, reforestation and deforestation activities (ARD. To evaluate these activities, Italy has to elaborate methods to estimate the conversion of non-forested to forested land, occurred after 31 December 1989. The aim of this study was to test a methodology to estimate the ARD activities. The approach was experimented in the Comunità Montana del Grappa (about 10500 ha considered as a pilot area in the Prealpine region (NE Italy. The land-use change relative to the forest area was assessed by multitemporal classification of 1131 sampling points on orthocorrected aerial photos relative to 1991, 1996 and 1999. The forest area based on different definitions (minimum land cover equal to 10%, 20% or 30% and minimum surface equal to 2000 m2 or 5000 m2 was also assessed. Between 1991 and 1999, the total increment of the forest area was equal to 224 ha. However, the estimated increment was strongly related to the minimum surface (2000 m2 vs 5000 m2 of the forest definition. The proposed procedure was relatively easy to implement and highlighted the role of ARD and revegetation to attain the goals appointed from the Kyoto Protocol.

  5. STRAWBERRY CRATER ROADLESS AREAS, ARIZONA.

    Science.gov (United States)

    Wolfe, Edward W.; Light, Thomas D.

    1984-01-01

    The results of a mineral survey conducted in the Strawberry Crater Roadless Areas, Arizona, indicate little promise for the occurrence of metallic mineral or fossil fuel resources in the area. The area contains deposits of cinder, useful for the production of aggregate block, and for deposits of decorative stone; however, similar deposits occur in great abundance throughout the San Francisco volcanic field outside the roadless areas. There is a possibility that the Strawberry Crater Roadless Areas may overlie part of a crustal magma chamber or still warm pluton related to the San Francisco Mountain stratovolcano or to basaltic vents of late Pleistocene or Holocene age. Such a magma chamber or pluton beneath the Strawberry Crater Roadless Areas might be an energy source from which a hot-, dry-rock geothermal energy system could be developed, and a probable geothermal resource potential is therefore assigned to these areas. 9 refs.

  6. Gaseous mercury fluxes from forest soils in response to forest harvesting intensity: A field manipulation experiment

    Science.gov (United States)

    M. Mazur; C.P.J. Mitchell; C.S. Eckley; S.L. Eggert; R.K. Kolka; S.D. Sebestyen; E.B. Swain

    2014-01-01

    Forest harvesting leads to changes in soil moisture, temperature and incident solar radiation, all strong environmental drivers of soil-air mercury (Hg) fluxes. Whether different forest harvesting practices significantly alter Hg fluxes from forest soils is unknown.We conducted a field-scale experiment in a northern Minnesota deciduous forest wherein gaseous Hg...

  7. Quantifying the Carbon Balance of Forest Restoration and Wildfire under Projected Climate in the Fire-Prone Southwestern US

    Science.gov (United States)

    2017-01-01

    Climate projections for the southwestern US suggest a warmer, drier future and have the potential to impact forest carbon (C) sequestration and post-fire C recovery. Restoring forest structure and surface fire regimes initially decreases total ecosystem carbon (TEC), but can stabilize the remaining C by moderating wildfire behavior. Previous research has demonstrated that fire maintained forests can store more C over time than fire suppressed forests in the presence of wildfire. However, because the climate future is uncertain, I sought to determine the efficacy of forest management to moderate fire behavior and its effect on forest C dynamics under current and projected climate. I used the LANDIS-II model to simulate carbon dynamics under early (2010–2019), mid (2050–2059), and late (2090–2099) century climate projections for a ponderosa pine (Pinus ponderosa) dominated landscape in northern Arizona. I ran 100-year simulations with two different treatments (control, thin and burn) and a 1 in 50 chance of wildfire occurring. I found that control TEC had a consistent decline throughout the simulation period, regardless of climate. Thin and burn TEC increased following treatment implementation and showed more differentiation than the control in response to climate, with late-century climate having the lowest TEC. Treatment efficacy, as measured by mean fire severity, was not impacted by climate. Fire effects were evident in the cumulative net ecosystem exchange (NEE) for the different treatments. Over the simulation period, 32.8–48.9% of the control landscape was either C neutral or a C source to the atmosphere and greater than 90% of the thin and burn landscape was a moderate C sink. These results suggest that in southwestern ponderosa pine, restoring forest structure and surface fire regimes provides a reasonable hedge against the uncertainty of future climate change for maintaining the forest C sink. PMID:28046079

  8. Impacts of human activity and climate on the hydrology and ecosystem services of forests in the Guianas on the northern rim of Amazonia

    Science.gov (United States)

    Parkin, G.; Wagner, T.; Bovolo, I.; Pereira, R.

    2010-12-01

    Tropical deforestation is one of the main areas of international concern in relation to increases in atmospheric carbon dioxide and feedbacks between land cover and climate. The Guiana Shield region, including the Guianas (Guyana, Surinam, and French Guiana), contains one of the largest remaining continuous areas of tropical forest on the Earth, and is therefore of international importance for climate stability. Its importance to the regional climate of South America is also potentially significant, as a possible conduit for vapour transport between the Caribbean and the continental interior. However, recent studies have confirmed the paucity of reliable hydrometeorological data in the forested interior in the Guianas that could help to improve understanding of these macro-scale links as well as the more local impacts of forest activities. A new hydrological monitoring programme has been established at the Iwokrama International Centre for Rainforest Conservation and Development in the interior of Guyana to provide evidence related to the impacts of forest activities and climate on ecosystem services provided by the forest. These services include water, carbon and nutrient cycling that are essential for maintaining biodiversity and other indicators necessary for long-term sustainability of the forest environment. The Iwokrama Centre aims to test the concept of a truly sustainable forest where conservation, environmental balance and economic use are mutually reinforcing. Iwokrama is uniquely placed for this research, in that it has integral involvement of the indigenous forest communities, and is geographically situated at a transition between mature intact forest and a savannah region that is likely to be sensitive to climate change, and on a larger scale at a transition between distinctive climate types in the coastal region of the Guianas influenced by the Equatorial Trough and the Amazonian interior which experiences a more continental type climate. The

  9. Discovery of a possible hybrid of the Critically Endangered Forest Owlet Athene blewitti and Spotted Owlet Athene brama (Aves: Strigiformes from northern Maharashtra, India

    Directory of Open Access Journals (Sweden)

    S.A. Pande

    2011-04-01

    Full Text Available The Forest Owlet Athene blewitti is considered to be critically endangered and at an extremely high risk of extinction. It was recently rediscovered after 113 years and little is known about this endemic species, which has a very limited distribution in central India. In early February 2004, the Earth Lovers Association (ELA and the International Birding and Research Centre in Eilat (IBRCE arranged an expedition to the Melghat Tiger Reserve (MTR and mapped all known and newly discovered territories of Forest and Spotted owlets (A. brama

  10. Caracterización, distribución y manejo de los bosques nativos en el norte de Uruguay Characterization, distribution and management of native forests in northern Uruguay

    Directory of Open Access Journals (Sweden)

    Ignacio P. Traversa-Tejero

    2013-03-01

    Full Text Available Los bosques del norte de Uruguay sufren de procesos de transformación del territorio y degradación, actualmente existe escasa información sobre la estructura y composición florística de las comunidades arbóreas que sirva como base para estudiar su dinámica. Se analizó la distribución, la composición arbórea y el manejo silvícola de los bosques de la región de Rivera, Uruguay. El área de estudio comprende 33 000 ha delimitadas mediante 2 criterios, uno natural (cuenca hidrológica y otro socioeconómico (ciudad de referencia. La información proveniente de inventarios florísticos y encuestas a productores fue ingresada a un sistema de información geográfica. Los bosques se agruparon de acuerdo al gradiente hídrico asociado con curvas de nivel. La superficie de los bosques ocupa el 13.9% del área de estudio (región de Rivera, cifra que triplica la superficie de bosques existente a nivel nacional. Se registraron 60 especies leñosas. Las familias con mayor frecuencia fueron Anacardiaceae (26.5% y Euphorbiaceae (14.7%. Las Anacardiaceae son más frecuentes en los bosques subxerófilos y las Euphorbiaceae en los bosques hidrófilos. Todos los bosques son vulnerables debido a la mayor importancia que se concede a la ganadería, sin que exista un manejo integrado de los bosques que contemple la multifuncionalidad de usos (silvicultura y ganadería. Los bosques cercanos a la ciudad están más degradados debido a la presencia de especies exóticas.The northern region of Uruguay undergoes land transformation processes, and degradation of native forest. The existing information on the structure and floristic composition of the forests in that region, as a basis for studies about dynamics, is scarce. Species distribution, floristic composition (wooden species and forest management, was assessed in the Rivera Region, Uruguay. The study area (33 000 ha was delimited by 2 simultaneous and complementary approaches, the first one natural

  11. Residual effects of thinning and high white-tailed deer densities on northern redback salamanders in southern New England oak forests

    Science.gov (United States)

    Robert T. Brooks

    1999-01-01

    Research has demonstrated that even-aged regeneration harvests, especially clearcutting, can have a major and long-lasting detrimental effect on forest amphibians, but the effects of less intensive silvicultural treatments have not been well documented. Additionally, the chronic overabundance of white-tailed deer (Odocoileus virginianus) has become a...

  12. Historical framework to explain long-term coupled human and natural system feedbacks: application to a multiple-ownership forest landscape in the northern Great Lakes region, USA

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    Michelle M. Steen-Adams

    2015-03-01

    Full Text Available Current and future human and forest landscape conditions are influenced by the cumulative, unfolding history of social-ecological interactions. Examining past system responses, especially unintended consequences, can reveal valuable insights that promote learning and adaptation in forest policy and management. Temporal couplings are complex, however; they can be difficult to trace, characterize, and explain. We develop a framework that integrates environmental history into analysis of coupled human and natural systems (CHANS. Our study demonstrates how historical data and methods can help to explain temporal complexity of long-term CHANS feedbacks. We focus on two sources of temporal complexity: legacy effects and lagged interactions. We apply our framework to a multiple-ownership forest landscape comprising tribal and nonindustrial private forest ownerships in Wisconsin. Our framework features four elements that help investigators better understand complex systems through time: (1 a temporal axis parsed into historical periods (periodization, (2 representation of links between historical periods and system feedbacks, (3 representation of land ownership history, and (4 nested geographical scales of historical analysis. The framework can help to reveal legacy effects and lagged interactions, illuminate turning points and periods in system dynamics, and distil insights from unintended consequences that inform institutional and policy adaptation. We also assess the validity of using land ownership to represent the social component of CHANS models. When treated as a categorical variable and interpreted in historical context, land ownership can validly represent decision-making structure, culture, and knowledge system in spatially explicit social-ecological models.

  13. The influence of spruce on acidity and nutrient content in soils of Northern Taiga dwarf shrub-green moss spruce forests

    Science.gov (United States)

    Orlova, M. A.; Lukina, N. V.; Smirnov, V. E.; Artemkina, N. A.

    2016-11-01

    Presently, among the works considering the influence of forest trees on soil properties, the idea that spruce ( Picea abies) promotes the acidification of soils predominates. The aim of this work is to assess the effects of spruce trees of different ages and Kraft classes on the acidity and content of available nutrient compounds in the soils under boreal dwarf shrub-green moss spruce forests by the example of forest soils in the Kola Peninsula. The soils are typical iron-illuvial podzols (Albic Rustic Podzols (Arenic)). Three probable ways of developing soils under spruce forests with the moss-dwarf shrub ground cover are considered. The soils under windfall-soil complexes of flat mesodepressions present the initial status. The acidity of organic soil horizons from the initial stage of mesodepression overgrowth to the formation of adult trees changed nonlinearly: the soil acidity reached its maximum under the 30-40-year-old trees and decreased under the trees older than 100 years. The contents of nitrogen and available nutrients increased. The acidity of the mineral soil horizons under the trees at the ages of 110-135 and 190-220 years was comparable, but higher than that under the 30-40-year-old trees. The differences in the strength and trends of the trees' effect on the soils are explained by the age of spruce trees and their belonging to different Kraft classes.

  14. Arizona Measure of Academic Progress: A First Look at Growth in Arizona Schools.

    Science.gov (United States)

    Garcia, David; Aportela, Anabel

    The Arizona Measure of Academic Progress (MAP) was developed using the Stanford 9 Achievement Test (SAT9) scores for the period from Spring 1998 to Spring 1999. The Research and Policy Division of the Arizona Department of Education matched students who took the SAT9 in Spring of 1998 and 1999. On average, 89% of students were matched per grade…

  15. Views from Inside a Pediatric Clinic: How Arizona's Political Climate Has Impacted Arizona's Youngest Latino Learners

    Science.gov (United States)

    Jimenez-Silva, Margarita; Cheatham, Gregory A.; Gomez, Laura

    2013-01-01

    It is critical that we examine impacts that recent immigration policies such as SB1070 are having on Arizona's youngest Latino learners.The large number of Latinos under the age of five, and the impact that this upcoming generation of Latinos will have on all aspects of life in Arizona merits a closer look. In this qualitative study, we examined…

  16. 77 FR 25741 - Notice of Inventory Completion: Arizona State Museum, University of Arizona, Tucson, AZ

    Science.gov (United States)

    2012-05-01

    ... Reservation, Arizona; and the Tohono O'odham Nation of Arizona. History and Description of the Remains In 1930... individuals were identified. The three associated funerary objects are one ceramic bowl, one ceramic jar, and one ceramic pitcher. Queen Creek Ruin was a large habitation site that included trash mounds,...

  17. 78 FR 13889 - Notice of Intent To Repatriate Cultural Items: Arizona State Museum, University of Arizona...

    Science.gov (United States)

    2013-03-01

    ...) to the Arizona Historical Society. In 1991, the object was transferred to the Arizona State Museum as... through identification by Hopi cultural specialists. Specific knowledge provided by the Society Priests of... by the Momngwit in the Hopi villages for the practice of the Hopi Religion. The Hopi...

  18. Comparing the impacts of mature spruce forests and grasslands on snow melt, water resource recharge, and run-off in the northern boreal environment

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    Jiří Kremsa

    2015-03-01

    Full Text Available Snow-melt runoff is an important factor in control of flooding and soil erosion in higher and cold regions of the world. In 1992–2008–2008, processes of snow accumulation and melting were monitored at two adjacent sites of the Paljakka environmental research centre (Finland. The forest stand of mature spruce (Picea abies has been compared with adjacent, local, and open grassland. In the forest, snowpack duration fluctuated for 180–245 days, with a maximum depth of 78–152 cm and snow–water content of 167–406 mm, while in the open grassland this occurred for some 20 days less, with maximum depth 65–122 cm, and snow–water content 143–288 mm. The snow–water captured in the canopy reached a maximum 27% of that registered on the ground; the loss of intercepted snow by sublimation was approximately 26% of the annual snowfall. During the high melt period (April–May, the degree-day factor in the forest stand achieved 60% of values observed in the grassland (2.3–3.5 against 3.8–6.0 mm °C−1 day−1. The hydrological model BROOK 90 was employed to analyse potential water resources recharge, and flood risk at Paljakka. Considering the normal climate season, snow-melt runoff from the forest exceeded the grassland by 22% (225 against 185 mm. In extreme situations, the maximum daily runoff from snow-melt in the grasslands (57 mm day−1 exceeded 2.6 times the values in spruce forest (22 mm day−1.

  19. 基于生态保护格局的长白山北部森林景观特征分析%Analysis of landscape characteristics of forests in northern Changbai Mountains based on ecological protection pattern

    Institute of Scientific and Technical Information of China (English)

    王健铭; 张天汉; 于琳倩; 董芳宇; 李景文; 李俊清; 赵秀海

    2015-01-01

    本研究旨在分析长白山林区北部景观格局特征,并以此作为未来生物多样性保护与构建长白山地区整体森林保护格局的依据。基于泉阳和露水河林业局森林资源二类调查资料和林相图,利用Arcgis和Fragstats等软件,从土地利用类型、优势树种和龄组的角度,分析了景观构成要素和森林保护现状,在景观水平和斑块水平上分析了该区景观格局指数特征。结果表明:有林地主导着土地利用类型,森林景观优势明显,研究区整体景观存在破碎化,优势景观类型破碎化程度比较严重;森林景观中各优势树种和龄组景观的优势度较弱,景观连通性较差,树种与林龄结构复杂,景观破碎化更为严重;幼龄林是破碎化最严重的龄组。人为活动对优势树种和林龄组成有着显著的影响,人为干扰是景观破碎化的最主要原因。根据分析结果,该区应科学规划城镇化建设,引导作物栽培合理开展,改善景观破碎化现状并建立有效的生态廊道,提高森林生态系统的生物多样性和稳定性。%This study aims to analyze the landscape pattern of Quanyang and Lushuihe forestry bureaus in northern Changbai Mountains, and thus provide basis for future biodiversity conservation and construction of overall forest protection in Changbai Mountains. Based on the forest resources inventories and forest type maps, we analyzed the landscape elements and forest protection situation by using spatial analysis software Arcgis and Fragstats. The forest structure and landscape pattern were studied in terms of land-use type, dominant tree species and age group. Combined with overlay analysis of forest type map and landscape situation, suggestions on management of each planning area are proposed. The results showed that forest is the dominated land use type, showing apparent superiority in forest landscape; however, fragmentation exists in the

  20. Comparação entre solos sob uso agroflorestal e em florestas remanescentes adjacentes, no norte de Rondônia Comparison of soils used for agroforestry and of remaining forests, in northern Rondônia State, Brazil

    Directory of Open Access Journals (Sweden)

    José Maria Thomaz Menezes

    2008-04-01

    Full Text Available A importância e a eficácia dos sistemas agroflorestais na conservação dos solos tropicais necessitam de comprovações demonstrativas localizadas. Atributos físicos e químicos dos solos de sete parcelas com cinco anos e meio de uso agroflorestal, avaliados na camada de 0-0,2 m, foram comparados aos respectivos solos de florestas remanescentes adjacentes no norte do Estado de Rondônia. Não foram constatadas diferenças na composição granulométrica entre os solos na camada avaliada, sugerindo que os dois sistemas localizam-se sob o mesmo tipo de solo numa mesma propriedade rural. Nos solos sob sistemas agroflorestais, os valores de pH, Ca e Mg foram sempre maiores do que os dos solos das florestas remanescentes adjacentes, o que é atribuído ao aporte de nutrientes que restaram da queima anterior da floresta, ocorrida entre um e oito anos antes da instalação do sistema agroflorestal. Os teores de matéria orgânica, P e K do solo nos sistemas agroflorestais mantiveram-se com valores semelhantes aos da floresta, cinco anos e meio depois de sua instalação, indicando que esses sistemas preservaram algumas propriedades químicas do solo durante o período considerado.The importance and efficiency of agroforestry systems in the conservation of tropical soils need to be demonstrated at the local scale. Physical and chemical soil attributes of seven plots used for agroforestry during 5.5 years were evaluated in the 0-0.2 m layer and compared with the respective soils of adjacent forests fragments in the Northern Rondônia State. No differences in texture were found between the soils in the layer evaluated, indicating that the two systems are located on the same soil type. In the soils under agroforestry systems, the values of pH, calcium and magnesium were always higher than in the soils of the adjacent forest fragments, which are ascribed to the nutrients released by the previous forest slashing and burning, between one and eight years

  1. Emissions of forest floor and mineral soil carbon, nitrogen and mercury pools and relationships with fire severity for the Pagami Creek Fire in the Boreal Forest of northern Minnesota

    Science.gov (United States)

    Randall K. Kolka; Brian R. Sturtevant; Jessica R. Miesel; Aditya Singh; Peter T. Wolter; Shawn Fraver; Thomas M. DeSutter; Phil A. Townsend

    2017-01-01

    Forest fires cause large emissions of C (carbon), N (nitrogen) and Hg (mercury) to the atmosphere and thus have important implications for global warming (e.g. via CO2 and N2O emissions), anthropogenic fertilisation of natural ecosystems (e.g. via N deposition), and bioaccumulation of harmful metals in aquatic and...

  2. Plague studies in California: a review of long-term disease activity, flea-host relationships and plague ecology in the coniferous forests of the Southern Cascades and northern Sierra Nevada mountains.

    Science.gov (United States)

    Smith, Charles R; Tucker, James R; Wilson, Barbara A; Clover, James R

    2010-06-01

    We review 28 years of long-term surveillance (1970-1997) for plague activity among wild rodents from ten locations within three coniferous forest habitat types in the northern Sierra Nevada and the Southern Cascade mountains of northeastern California. We identify rodent hosts and their fleas and document long-term plague activity in each habitat type. The highest seroprevalence for Yersinia pestis occurred in the chipmunks, Tamias senex and T. quadrimaculatus, and the pine squirrel, Tamiasciurus douglasii. The most commonly infected fleas were Ceratophyllus ciliatus and Eumolpianus eumolpi from chipmunks and Oropsylla montana and O. idahoensis from ground squirrels. Serological surveillance demonstrated that populations of T. senex, T. quadrimaculatus and T. douglasii are moderately resistant to plague, survive infection, and are, therefore, good sentinels for plague activity. Recaptured T. senex and T. quadrimaculatus showed persistence of plague antibodies and evidence of re-infection over a two year period. These rodent species, their fleas, and the ecological factors common to the coniferous forest habitats likely promote the maintenance of plague foci in northeastern California.

  3. 3D View of Grand Canyon, Arizona

    Science.gov (United States)

    2000-01-01

    The Grand Canyon is one of North America's most spectacular geologic features. Carved primarily by the Colorado River over the past six million years, the canyon sports vertical drops of 5,000 feet and spans a 445-kilometer-long stretch of Arizona desert. The strata along the steep walls of the canyon form a record of geologic time from the Paleozoic Era (250 million years ago) to the Precambrian (1.7 billion years ago).The above view was acquired by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument aboard the Terra spacecraft. Visible and near infrared data were combined to form an image that simulates the natural colors of water and vegetation. Rock colors, however, are not accurate. The image data were combined with elevation data to produce this perspective view, with no vertical exaggeration, looking from above the South Rim up Bright Angel Canyon towards the North Rim. The light lines on the plateau at lower right are the roads around the Canyon View Information Plaza. The Bright Angel Trail, which reaches the Colorado in 11.3 kilometers, can be seen dropping into the canyon over Plateau Point at bottom center. The blue and black areas on the North Rim indicate a forest fire that was smoldering as the data were acquired on May 12, 2000.Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, Calif., is the U.S. Science team leader; Moshe Pniel of JPL is the project manager. ASTER is the only high resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as

  4. Temporal Variation in Water Quality Parameters under Different Vegetative Communities in Two Flooded Forests of the Northern Pantanal, Mato Grosso, Brazil

    Science.gov (United States)

    Couto, E. G.; Dalmagro, H. J.; Lathuilliere, M. J.; Pinto Junior, O. B.; Johnson, M. S.

    2013-12-01

    The Pantanal is one of the largest flood plains in the world, and is characterized by large variability in vegetative communities and flooding dynamics. Some woody plant species have been observed to colonize large areas forming monospecific stands. We measured chemical parameters of flood waters including dissolved organic carbon (DOC), nitrate (NO3), dissolved oxygen (DO), and carbon dioxide (CO2) as well as physical parameters such as photosynthetically active radiation (PAR), temperature (Tw), turbidity (Turb) and water levels (WL). These chemical and physical measurements were conducted with the intent to characterize spatial and temporal differences of monospecific stands in order to understand if these different formations alter the biogeochemistry of the Pantanal waters. Water sample campaigns were conducted during the inundation period of January to May 2013 in two areas located in the Private Reserve of the Brazilian Social Service of Commerce (RPPN-SESC) near Poconé, Mato Grosso. Research sites included: (1) a flooded tall-stature forest (known as Cambarazal) dominated by the Vochysia divergens species; and (2) in a flooded scrub forest (known as Baia das Pedras) dominated by the Combretum lanceolatum species. Results showed three principal factors which explained 80% of variance in aquatic physical and chemical parameters. The first factor (PCA-1) explained 38% of variance (DO, PAR and WL), PCA-2 explained 23% (NO3, Tw, DOC), while PCA-3 explained only 19% of variance (CO2 and Turb). During the entire study period, the major concentration of variables were observed in the flooded forest. Physical variables presented small alterations, with the exception of water levels, that were greater in the flooded forest. With respect to temporal variables, all chemical parameters were greater at the beginning of the inundation and gradually dropped with the water level. With this work, we observed that the different monospecific formations influenced water

  5. Detection of Olea europaea subsp. cuspidata and Juniperus procera in the dry Afromontane forest of northern Ethiopia using subpixel analysis of Landsat imagery

    Science.gov (United States)

    Hishe, Hadgu; Giday, Kidane; Neka, Mulugeta; Soromessa, Teshome; Van Orshoven, Jos; Muys, Bart

    2015-01-01

    Comprehensive and less costly forest inventory approaches are required to monitor the spatiotemporal dynamics of key species in forest ecosystems. Subpixel analysis using the earth resources data analysis system imagine subpixel classification procedure was tested to extract Olea europaea subsp. cuspidata and Juniperus procera canopies from Landsat 7 enhanced thematic mapper plus imagery. Control points with various canopy area fractions of the target species were collected to develop signatures for each of the species. With these signatures, the imagine subpixel classification procedure was run for each species independently. The subpixel process enabled the detection of O. europaea subsp. cuspidata and J. procera trees in pure and mixed pixels. Total of 100 pixels each were field verified for both species. An overall accuracy of 85% was achieved for O. europaea subsp. cuspidata and 89% for J. procera. A high overall accuracy level of detecting species at a natural forest was achieved, which encourages using the algorithm for future species monitoring activities. We recommend that the algorithm has to be validated in similar environment to enrich the knowledge on its capability to ensure its wider usage.

  6. Age-related and stand-wise estimates of carbon stocks and sequestration in the aboveground coarse wood biomass of wetland forests in the northern Pantanal, Brazil

    Science.gov (United States)

    Schöngart, J.; Arieira, J.; Felfili Fortes, C.; Cezarine de Arruda, E.; Nunes da Cunha, C.

    2011-11-01

    In this study we use allometric models combined with tree ring analysis to estimate carbon stocks and sequestration in the aboveground coarse wood biomass (AGWB) of wetland forests in the Pantanal, located in central South America. In four 1-ha plots in stands characterized by the pioneer tree species Vochysia divergens Pohl (Vochysiaceae) forest inventories (trees ≥10 cm diameter at breast height, D) have been performed and converted to estimates of AGWB by two allometric models using three independent parameters (D, tree height H and wood density ρ). We perform a propagation of measurement errors to estimate uncertainties in the estimates of AGWB. Carbon stocks of AGWB vary from 7.8 ± 1.5 to 97.2 ± 14.4 Mg C ha-1 between the four stands. From models relating tree ages determined by dendrochronological techniques to C-stocks in AGWB we derived estimates for C-sequestration which differs from 0.50 ± 0.03 to 3.34 ± 0.31 Mg C ha-1 yr-1. Maps based on geostatistic techniques indicate the heterogeneous spatial distribution of tree ages and C-stocks of the four studied stands. This distribution is the result of forest dynamics due to the colonizing and retreating of V. divergens and other species associated with pluriannual wet and dry episodes in the Pantanal, respectively. Such information is essential for the management of the cultural landscape of the Pantanal wetlands.

  7. SOURCE PHENOMENOLOGY EXPERIMENTS IN ARIZONA

    Energy Technology Data Exchange (ETDEWEB)

    Jessie L. Bonner; Brian Stump; Mark Leidig; Heather Hooper; Xiaoning (David) Yang; Rongmao Zhou; Tae Sung Kim; William R. Walter; Aaron Velasco; Chris Hayward; Diane Baker; C. L. Edwards; Steven Harder; Travis Glenn; Cleat Zeiler; James Britton; James F. Lewkowicz

    2005-09-30

    The Arizona Source Phenomenology Experiments (SPE) have resulted in an important dataset for the nuclear monitoring community. The 19 dedicated single-fired explosions and multiple delay-fired mining explosions were recorded by one of the most densely instrumented accelerometer and seismometer arrays ever fielded, and the data have already proven useful in quantifying confinement and excitation effects for the sources. It is very interesting to note that we have observed differences in the phenomenology of these two series of explosions resulting from the differences between the relatively slow (limestone) and fast (granodiorite) media. We observed differences at the two SPE sites in the way the rock failed during the explosions, how the S-waves were generated, and the amplitude behavior as a function of confinement. Our consortium's goal is to use the synergy of the multiple datasets collected during this experiment to unravel the phenomenological differences between the two emplacement media. The data suggest that the main difference between single-fired chemical and delay-fired mining explosion seismograms at regional distances is the increased surface wave energy for the latter source type. The effect of the delay-firing is to decrease the high-frequency P-wave amplitudes while increasing the surface wave energy because of the longer source duration and spall components. The results suggest that the single-fired explosions are surrogates for nuclear explosions in higher frequency bands (e.g., 6-8 Hz Pg/Lg discriminants). We have shown that the SPE shots, together with the mining explosions, are efficient sources of S-wave energy, and our next research stage is to postulate the possible sources contributing to the shear-wave energy.

  8. Forest report 2015; Waldzustandsbericht 2015

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-07-01

    This forest report of Lower Saxony (Germany) contains the following topics: Forestry Environment Monitoring, weather and climate, spring drought, insects and fungi, infiltrated substances, trends in soil solution of forest ecosystems, soil chemistry and root penetration in deeper layers of soil, climate change and sustainable land management in Northern German Plain.

  9. Element concentrations in surface soils of the Coconino Plateau, Grand Canyon region, Coconino County, Arizona

    Science.gov (United States)

    Van Gosen, Bradley S.

    2016-09-15

    This report provides the geochemical analyses of a large set of background soils collected from the surface of the Coconino Plateau in northern Arizona. More than 700 soil samples were collected at 46 widespread areas, sampled from sites that appear unaffected by mineralization and (or) anthropogenic contamination. The soils were analyzed for 47 elements, thereby providing data on metal concentrations in soils representative of the plateau. These background concentrations can be used, for instance, for comparison to metal concentrations found in soils potentially affected by natural and anthropogenic influences on the Coconino Plateau in the Grand Canyon region of Arizona.The soil sampling survey revealed low concentrations for the metals most commonly of environmental concern, such as arsenic, cobalt, chromium, copper, mercury, manganese, molybdenum, lead, uranium, vanadium, and zinc. For example, the median concentrations of the metals in soils of the Coconino Plateau were found to be comparable to the mean values previously reported for soils of the western United States.

  10. Ethnic Segregation in Arizona Charter Schools

    Directory of Open Access Journals (Sweden)

    Casey D. Cobb

    1999-01-01

    Full Text Available Among the criticisms of charter schools is their potential to further stratify schools along ethnic and class lines. This study addressed whether Arizona charter schools are more ethnically segregated than traditional public schools. In 1996-97, Arizona had nearly one in four of all charter schools in the United States. The analysis involved a series of comparisons between the ethnic compositions of adjacent charter and public schools in Arizona's most populated region and its rural towns. This methodology differed from the approach of many evaluations of charter schools and ethnic stratification in that it incorporated the use of geographic maps to compare schools' ethnic make-ups. The ethnic compositions of 55 urban and 57 rural charter schools were inspected relative to their traditional public school neighbors.

  11. March 2016 Arizona thoracic society ntoes

    Directory of Open Access Journals (Sweden)

    Robbins RA

    2016-03-01

    Full Text Available No abstract available. Article truncated at 150 words. The March 2016 Arizona Thoracic Society meeting was held on Wednesday, March 23, 2016 at the Scottsdale Shea Hospital beginning at 6:30 PM. This was a dinner meeting with case presentations. There were 17 in attendance representing the pulmonary, critical care, sleep, and radiology communities. Of note, Dr. Elijah Poulos drove from Flagstaff to attend the meeting. Dr. Rick Robbins gave a summary of ATS Hill Day and the possibility of collecting dues for the Arizona Thoracic Society along with American Thoracic Society dues. Dr. Robbins also presented the results of emailing the Table of Contents of the Southwest Journal of Pulmonary and Critical Care to the ATS members in Arizona, New Mexico, Colorado, and Nevada along with listing the contents in Inspirations the California Thoracic Society newsletter. The number of page views doubled over usual the following day. Dr. George Parides presented a short presentation on whether coccidioidomycosis nodules ...

  12. March 2014 Arizona thoracic society notes

    Directory of Open Access Journals (Sweden)

    Robbins RA

    2014-04-01

    Full Text Available No abstract available. Article truncated after 150 words. The March 2014 Arizona Thoracic Society meeting was a special meeting. In conjunction with the Valley Fever Center for Excellence and the Arizona Respiratory Center the Eighteenth Annual Farness Lecture was held in the Sonntag Pavilion at St. Joseph's Hospital at 6 PM on Friday, April 4, 2014. The guest speaker was Antonio "Tony" Catanzaro, MD from the University of California San Diego and current president of the Cocci Study Group. There were 57 in attendance representing the pulmonary, critical care, sleep, and infectious disease communities. After opening remarks by Arizona Thoracic Society president, Lewis Wesselius (a former fellow under Dr. Catanzaro at UCSD, John Galgiani, director of the Valley Fever Center for Excellence, gave a brief history of the Farness lecture before introducing Dr. Catanzaro. The lecture is named for Orin J. Farness, a Tucson physician, who was the first to report culture positive coccidioidomycosis (cocci or Valley Fever. ...

  13. Recovery of central Appalachian forested watershed

    Science.gov (United States)

    Mary Beth Adams; James N. Kochendenfer [sic

    2014-01-01

    The Fernow Experimental Forest (FEF) was established to conduct research in forest and watershed management in the central Appalachians. The 1868-ha FEF, located south of Parsons, West Virginia, is administered by the Northern Research Station of the USDA Forest Service and provides a valuable point of comparison with the Coweeta Hydrologic Laboratory (CHL), located in...

  14. Conservation of the Ethiopian church forests

    DEFF Research Database (Denmark)

    Aerts, Raf; Ortveld, Koev van; November, Eva

    2016-01-01

    In the central and northern highlands of Ethiopia, native forest and forest biodiversity is almost confined to sacred groves associated with churches. Local communities rely on these 'church forests' for essential ecosystem services including shade and fresh water but little is known about their ...

  15. Conservation of the Ethiopian church forests

    NARCIS (Netherlands)

    Aerts, Raf; Overtveld, Van Koen; November, Eva; Sterck, F.J.; Bongers, Frans

    2016-01-01

    In the central and northern highlands of Ethiopia, native forest and forest biodiversity is almost confined to sacred groves associated with churches. Local communities rely on these 'church forests' for essential ecosystem services including shade and fresh water but little is known about their

  16. Summer diet of the peregrine falcon in faunistically rich and poor zones of Arizona analyzed with capture-recapture modeling

    Science.gov (United States)

    Ellis, D.H.; Ellis, Catherine H.; Sabo, B.A.; Rea, A.M.; Dawson, J.; Fackler, J.K.; LaRue, C.T.; Grubb, T.G.; Schmitt, J.; Smith, D.G.; Kery, M.

    2004-01-01

    We collected prey remains from 25 Peregrine Falcon (Falco peregrinus) territories across Arizona from 1977 to 1988 yielding 58 eyrie-years of data. Along with 793 individual birds (107 species and six additional genera), we found seven mammals and nine insects. In addition, two nestling peregrines were consumed. We found a larger dependence upon White-throated Swifts (Aeronautes saxatalis) and birds on migration in northern Arizona, while in southeastern and central Arizona average prey mass was greater and columbiforms formed the largest dietary component. In northern, central, and southeastern Arizona, 74, 66, and 56 avian prey taxa, respectively, were recorded. We used capture-recapture modeling to estimate totals of 111 ? 9.5, 113 ? 10.5, and 86 ? 7.9 (SE) avian taxa taken in these same three areas. These values are counterintuitive inasmuch as the southeast has the richest avifauna. For the entire study area, 156 ? 9.3 avian taxa were estimated to be taken by peregrines.

  17. Western Pine Beetle Populations in Arizona and California Differ in the Composition of Their Aggregation Pheromones.

    Science.gov (United States)

    Pureswaran, Deepa S; Hofstetter, Richard W; Sullivan, Brian T; Grady, Amanda M; Brownie, Cavell

    2016-05-01

    We compared pheromone production and response for populations of western pine beetle, Dendroctonus brevicomis LeConte, from sites in northern Arizona and northern California. Volatiles were collected from individuals of both sexes that had mined as a pair in a Pinus ponderosa log for 1 d, and they were subsequently analyzed by gas chromatography coupled to mass-spectrometry. Principal component analysis of quantities of Dendroctonus pheromone components indicated strong site-associated clustering of blend composition for females but not males. Much of the clustering in females evidently was due to differences in the production of endo- and exo-brevicomin, which occurred in average ratios of 0.1:1 and 19:1 for populations in the California and Arizona sites, respectively. In the California site, exo- was better than endo-brevicomin in enhancing trap catches of both sexes to lures containing the host-tree odor α-pinene and the male-produced aggregation pheromone component frontalin. In an identical test in the Arizona site, endo- was a better adjuvant than exo-brevicomin for male attraction, whereas females did not show a significant preference. At neither location were the isomers antagonistic to one another in activity. Thus, one aggregation pheromone has apparently diverged between these populations, concurrent with published evidence that D. brevicomis on either side of the Great Basin are genetically distinct and are possibly different species. Furthermore, production of and response to the isomers of brevicomin by flying Dendroctonus frontalis Zimmermann in the Arizona site were similar to those of sympatric D. brevicomis. This interspecific signal overlap is likely sustainable since joint species mass-attacks may assist both species in overcoming host defenses, thereby increasing host availability.

  18. Geothermal resources in Arizona: a bibliography. Circular 23

    Energy Technology Data Exchange (ETDEWEB)

    Calvo, S.S.

    1982-01-01

    All reports and maps generated by the Geothermal Project of the Arizona Bureau of Geology and Mineral Technology and the Arizona Geothermal Commercialization Team of the University of Arizona are listed. In order to provide a more comprehensive listing of geothermal papers from other sources have been included. There are 224 references in the bibliography. (MHR)

  19. The relationship of Landsat digital data to the properties of Arizona rangelands

    Science.gov (United States)

    Horvath, Emil H.; Post, D. F.; Kelsey, J. B.

    1984-01-01

    Pedon descriptions, vegetation transect information, and Landsat digital data were obtained for 110 sites on the Tonto National Forest in central Arizona. Using the field and satellite data, 33 variables were evaluated and prediction models were generated using stepwise multiple regression techniques. The following six factors explained 84% of the variability within the sum of the values for the four Landsat spectral bands: sum of brush and forest crown densities, elevation, surface color, rock type, cobbles on the surface of the site, and grass cover. Seven factors explained 81% of the variability for the ratio of Bands 4 plus 5 to Bands 6 plus 7: percent clay in the surface horizon, percent fragments > 2 mm in the surface horizon, the sum of forest and brush crown densities, pH of the surface horizon, color of the surface horizon, litter cover, and site aspect.

  20. Geochemical map of the Arnold Mesa Roadless Area, Yavapai County, Arizona

    Science.gov (United States)

    Wolfe, Edward W.

    1983-01-01

    The Wilderness Act (Public Law 88-577, September 3, 1964) and related acts require the U.S. Geological Survey and the U.S. Bureau of Mines to survey certain areas on Federal lands to determine their mineral resource potential. Results must be made available to the public and be submitted to the President and the Congress. This report presents the results of a geochemical survey of the Arnold Mesa Roadless Area (U.S. Forest Service number 03092) in the Prescott and Tonto National Forests, Yavapai County, Arizona. The Arnold Mesa Roadless Area was classified as a further planning area during the Second Roadless Area Review and Evaluation (RARE II) by the U.S. Forest Service, January 1979.

  1. Effect of soil frost on growing season nitrogen uptake by fine roots of mature trees in northern hardwood forests of the United States

    Science.gov (United States)

    Socci, A. M.; Templer, P. H.

    2010-12-01

    Forests of the northeastern United States are predicted to experience a decrease in the depth and duration of the winter snowpack over the next 100 years. Even when coupled with warmer winter air temperatures, the absence of snow as insulation can increase soil frost during the winter months. Past research has determined that there are species-level effects of soil frost on dominant forest trees. For example, in stands dominated by sugar maple (Acer saccharum), induced soil frost led to increased fine root mortality and soil nitrate leaching. Soil frost also increased fine root mortality in stands dominated by yellow birch (Betula allegheniensis), but there was no significant change in leaching of soil nitrate. We hypothesized that greater nitrogen (N) losses from stands dominated by sugar maple may be due to reduced N uptake by fine roots of this tree species. To determine the impact of increased soil freezing on fine root uptake of N, we established a snow manipulation experiment in mixed sugar maple/American beech (Fagus grandifolia) forests at the Hubbard Brook Experimental Forest in New Hampshire (n=4 paired snow-removal and reference plots; each 13m X 13m). Snow removal occurred during the first six weeks of winter over two years. During each growing season following snow removal, we used the N depletion technique to measure in situ rates of uptake of ammonium and nitrate by fine roots of sugar maple during the early, peak and late growing season. Among all sampling dates and plots, we observed significantly lower uptake of N as nitrate compared to ammonium. During the first growing season, at moderate ammonium availability (35 μM N) we observed significantly less uptake of ammonium by fine roots of sugar maple in the snow removal plots relative to the reference plots during the early growing season (April-May), with no significant differences in uptake of ammonium during the peak (July) and late (September) growing season. We observed no differences in

  2. Biomass Accumulation and Net Primary Production during the Early Stage of Secondary Succession after a Severe Forest Disturbance in Northern Japan

    Directory of Open Access Journals (Sweden)

    Tomotsugu Yazaki

    2016-11-01

    Full Text Available Quantitative evaluations of biomass accumulation after disturbances in forests are crucially important for elucidating and predicting forest carbon dynamics in order to understand the carbon sink/source activities. During early secondary succession, understory vegetation often affects sapling growth. However, reports on biomass recovery in naturally-regenerating sites are limited in Japan. Therefore, we traced annual or biennial changes in plant species, biomass, and net primary production (NPP in a naturally regenerating site in Japan after windthrow and salvage-logging plantation for nine years. The catastrophic disturbance depleted the aboveground biomass (AGB from 90.6 to 2.7 Mg·ha−1, changing understory dominant species from Dryopteris spp. to Rubus idaeus. The mean understory AGB recovered to 4.7 Mg·ha−1 in seven years with the dominant species changing to invasive Solidago gigantea. Subsequently, patches of deciduous trees (mainly Betula spp. recovered whereas the understory AGB decreased. Mean understory NPP increased to 272 g·C·m−2·year−1 within seven years after the disturbance, but decreased thereafter to 189 g·C·m−2·year−1. Total NPP stagnated despite increasing overstory NPP. The biomass accumulation is similar to that of naturally regenerating sites without increase of trees in boreal and temperate regions. Dense ground vegetation an