1
|
Slabbert E, Knight T, Wubet T, Kautzner A, Baessler C, Auge H, Roscher C, Schweiger O. Abiotic factors are more important than land management and biotic interactions in shaping vascular plant and soil fungal communities. Glob Ecol Conserv 2022. [DOI: 10.1016/j.gecco.2021.e01960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
2
|
Coble AA, Barnard H, Du E, Johnson S, Jones J, Keppeler E, Kwon H, Link TE, Penaluna BE, Reiter M, River M, Puettmann K, Wagenbrenner J. Long-term hydrological response to forest harvest during seasonal low flow: Potential implications for current forest practices. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 730:138926. [PMID: 32402963 DOI: 10.1016/j.scitotenv.2020.138926] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 04/21/2020] [Accepted: 04/21/2020] [Indexed: 06/11/2023]
Abstract
Seasonal changes in the magnitude and duration of streamflow can have important implications for aquatic species, drinking water supplies, and water quality. In many regions, including the Pacific Northwest (U.S. and Canada), seasonal low flow is declining, primarily due to a changing climate, but is also influenced by urbanization, agriculture, and forestry. We review the responses of seasonal low flow, catchment storage, and tree-water relations to forest harvest over long timescales and discuss the potential implications of these responses for current forest practices and aquatic biota. We identify three distinct periods of expected low flow responses as regrowth occurs following forest harvest: in the first period an initial increase in low flow can occur as replanted stands regenerate, in the second period low flow is characterized by mixed and variable responses as forests become established, and in the third period, which follows canopy closure, low flow declines may occur over long timescales. Of 25 small catchments with ≥10 years post-harvest data, nine catchments had no change or variable low flow and 16 catchments experienced reduced low flow years after harvest. The retention of riparian buffers, limited size of harvest units, and adherence to reforestation requirements have altered the contemporary forest landscape relative to historical forest practices, but data documenting multi-decadal hydrological responses to current harvest practices is limited. Our review suggests that the magnitude of low flow responses attenuates downstream as a broader mosaic of stand ages occurs and multiple hydrological periods are represented. Declines were not observed in the seven large catchments reviewed. The consequences of low flow declines for aquatic biota are not well understood, but where data do exist aquatic biota have not been adversely affected. We identify priorities for future research that will aid in improving predictions of low flow responses to harvest as forests regenerate.
Collapse
Affiliation(s)
- Ashley A Coble
- National Council for Air and Stream Improvement, Inc., 227 NW Third St., Corvallis, OR 97330, USA.
| | - Holly Barnard
- Department of Geography, Institute of Arctic and Alpine Research University of Colorado, Boulder, CO, USA
| | - Enhao Du
- College of Natural Resources, University of Idaho, Moscow, ID, USA
| | - Sherri Johnson
- USDA Forest Service, Pacific Northwest Research Station, Corvallis, OR, USA
| | - Julia Jones
- Geography CEOAS, Oregon State University, Corvallis, OR, USA
| | - Elizabeth Keppeler
- USDA Forest Service, Pacific Southwest Research Station, Fort Bragg, CA, USA
| | - Hyojung Kwon
- Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR, USA
| | - Timothy E Link
- College of Natural Resources, University of Idaho, Moscow, ID, USA
| | - Brooke E Penaluna
- USDA Forest Service, Pacific Northwest Research Station, Corvallis, OR, USA
| | | | - Mark River
- Weyerhaeuser Company, Springfield, OR, USA
| | - Klaus Puettmann
- Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR, USA
| | | |
Collapse
|
3
|
Vorster AG, Evangelista PH, Stovall AEL, Ex S. Variability and uncertainty in forest biomass estimates from the tree to landscape scale: the role of allometric equations. CARBON BALANCE AND MANAGEMENT 2020; 15:8. [PMID: 32410068 PMCID: PMC7227279 DOI: 10.1186/s13021-020-00143-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 05/04/2020] [Indexed: 06/01/2023]
Abstract
BACKGROUND Biomass maps are valuable tools for estimating forest carbon and forest planning. Individual-tree biomass estimates made using allometric equations are the foundation for these maps, yet the potentially-high uncertainty and bias associated with individual-tree estimates is commonly ignored in biomass map error. We developed allometric equations for lodgepole pine (Pinus contorta), ponderosa pine (P. ponderosa), and Douglas-fir (Pseudotsuga menziesii) in northern Colorado. Plot-level biomass estimates were combined with Landsat imagery and geomorphometric and climate layers to map aboveground tree biomass. We compared biomass estimates for individual trees, plots, and at the landscape-scale using our locally-developed allometric equations, nationwide equations applied across the U.S., and the Forest Inventory and Analysis Component Ratio Method (FIA-CRM). Total biomass map uncertainty was calculated by propagating errors from allometric equations and remote sensing model predictions. Two evaluation methods for the allometric equations were compared in the error propagation-errors calculated from the equation fit (equation-derived) and errors from an independent dataset of destructively-sampled trees (n = 285). RESULTS Tree-scale error and bias of allometric equations varied dramatically between species, but local equations were generally most accurate. Depending on allometric equation and evaluation method, allometric uncertainty contributed 30-75% of total uncertainty, while remote sensing model prediction uncertainty contributed 25-70%. When using equation-derived allometric error, local equations had the lowest total uncertainty (root mean square error percent of the mean [% RMSE] = 50%). This is likely due to low-sample size (10-20 trees sampled per species) allometric equations and evaluation not representing true variability in tree growth forms. When independently evaluated, allometric uncertainty outsized remote sensing model prediction uncertainty. Biomass across the 1.56 million ha study area and uncertainties were similar for local (2.1 billion Mg; % RMSE = 97%) and nationwide (2.2 billion Mg; % RMSE = 94%) equations, while FIA-CRM estimates were lower and more uncertain (1.5 billion Mg; % RMSE = 165%). CONCLUSIONS Allometric equations should be selected carefully since they drive substantial differences in bias and uncertainty. Biomass quantification efforts should consider contributions of allometric uncertainty to total uncertainty, at a minimum, and independently evaluate allometric equations when suitable data are available.
Collapse
Affiliation(s)
- Anthony G Vorster
- Natural Resource Ecology Laboratory, Colorado State University, Fort Collins, CO, 80523, USA.
- Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO, 80523, USA.
| | - Paul H Evangelista
- Natural Resource Ecology Laboratory, Colorado State University, Fort Collins, CO, 80523, USA
- Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO, 80523, USA
| | | | - Seth Ex
- Department of Forest and Rangeland Stewardship, Colorado State University, Fort Collins, CO, 80523, USA
| |
Collapse
|
4
|
Factors Affecting Spatial Variation in Vegetation Carbon Density in Pinus massoniana Lamb. Forest in Subtropical China. FORESTS 2019. [DOI: 10.3390/f10100880] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Carbon density is an important indicator of carbon sequestration capacity in forest ecosystems. We investigated the vegetation carbon density of Pinus massoniana Lamb. forest in the Jiangxi Province. Based on plots investigation and measurement of the carbon content of the samples, the influencing factors and spatial variation of vegetation carbon density (including the tree layer, understory vegetation layer and litter layer) were analysed. The results showed that the average vegetation carbon density value of P. massoniana forest was 52 Mg·ha−1. The vegetation carbon density was significantly (p < 0.01) and positively correlated with the stand age, mean annual precipitation, elevation and stand density and negatively correlated with the slope and mean annual temperature. Forest management had a significant impact on vegetation carbon density. To manage P. massoniana forest for carbon sequestration as the primary objective, near-natural forest management theory should be followed, e.g., replanting broadleaf trees. These measures would promote positive succession and improve the vegetation carbon sequestration capacity of forests. The results from the global Moran’s I showed that the vegetation carbon density of P. massoniana forest had significant positive spatial autocorrelation. The results of local Moran’s I showed that the high-high spatial clusters were mainly distributed in the southern, western and eastern parts of the province. The low-low spatial clusters were distributed in the Yushan Mountains and in the northern part of the province. The fitting results of the semivariogram models showed that the spherical model was the best fitting model for vegetation carbon density. The ratio of nugget to sill was 0.45, indicating a moderate spatial correlation of carbon density. The vegetation carbon density based on kriging spatial interpolation was mainly concentrated in the range of 32.5–69.8 Mg·ha−1. The spatial distribution of vegetation carbon density regularity was generally low in the middle region and high in the peripheral region, which was consistent with the terrain characteristics of the study area.
Collapse
|
5
|
Mattson KG, Zhang J. Forests in the northern Sierra Nevada of California, USA, store large amounts of carbon in different patterns. Ecosphere 2019. [DOI: 10.1002/ecs2.2778] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Kim G. Mattson
- Ecosystems Northwest 189 Shasta Avenue Mount Shasta California 96067 USA
| | - Jianwei Zhang
- Pacific Southwest Research Station USDA Forest Service 3644 Avtech Parkway Redding California 96002 USA
| |
Collapse
|
6
|
Jucker T, Hardwick SR, Both S, Elias DMO, Ewers RM, Milodowski DT, Swinfield T, Coomes DA. Canopy structure and topography jointly constrain the microclimate of human-modified tropical landscapes. GLOBAL CHANGE BIOLOGY 2018; 24:5243-5258. [PMID: 30246358 DOI: 10.1111/gcb.14415] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 07/02/2018] [Indexed: 05/05/2023]
Abstract
Local-scale microclimatic conditions in forest understoreys play a key role in shaping the composition, diversity and function of these ecosystems. Consequently, understanding what drives variation in forest microclimate is critical to forecasting ecosystem responses to global change, particularly in the tropics where many species already operate close to their thermal limits and rapid land-use transformation is profoundly altering local environments. Yet our ability to characterize forest microclimate at ecologically meaningful scales remains limited, as understorey conditions cannot be directly measured from outside the canopy. To address this challenge, we established a network of microclimate sensors across a land-use intensity gradient spanning from old-growth forests to oil-palm plantations in Borneo. We then combined these observations with high-resolution airborne laser scanning data to characterize how topography and canopy structure shape variation in microclimate both locally and across the landscape. In the processes, we generated high-resolution microclimate surfaces spanning over 350 km2 , which we used to explore the potential impacts of habitat degradation on forest regeneration under both current and future climate scenarios. We found that topography and vegetation structure were strong predictors of local microclimate, with elevation and terrain curvature primarily constraining daily mean temperatures and vapour pressure deficit (VPD), whereas canopy height had a clear dampening effect on microclimate extremes. This buffering effect was particularly pronounced on wind-exposed slopes but tended to saturate once canopy height exceeded 20 m-suggesting that despite intensive logging, secondary forests remain largely thermally buffered. Nonetheless, at a landscape-scale microclimate was highly heterogeneous, with maximum daily temperatures ranging between 24.2 and 37.2°C and VPD spanning two orders of magnitude. Based on this, we estimate that by the end of the century forest regeneration could be hampered in degraded secondary forests that characterize much of Borneo's lowlands if temperatures continue to rise following projected trends.
Collapse
Affiliation(s)
- Tommaso Jucker
- Forest Ecology and Conservation group, Department of Plant Sciences, University of Cambridge, Cambridge, UK
- CSIRO Land and Water, Floreat, WA, Australia
| | - Stephen R Hardwick
- Blackett Laboratory, Department of Physics, Imperial College London, London, UK
| | - Sabine Both
- School of Environmental and Rural Science, University of New England, Armidale, NSW, Australia
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK
| | - Dafydd M O Elias
- Lancaster Environment Centre, Lancaster University, Lancaster, UK
- Centre for Ecology & Hydrology, Lancaster Environment Centre, Lancaster, UK
| | | | | | - Tom Swinfield
- Forest Ecology and Conservation group, Department of Plant Sciences, University of Cambridge, Cambridge, UK
| | - David A Coomes
- Forest Ecology and Conservation group, Department of Plant Sciences, University of Cambridge, Cambridge, UK
| |
Collapse
|
7
|
Determinants of Above-Ground Biomass and Its Spatial Variability in a Temperate Forest Managed for Timber Production. FORESTS 2018. [DOI: 10.3390/f9080490] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The proper estimation of above-ground biomass (AGB) stocks of managed forests is a prerequisite to quantifying their role in climate change mitigation. The aim of this study was to analyze the spatial variability of AGB and its uncertainty between actively managed pine and unmanaged pine-oak reference forests in central Mexico. To investigate the determinants of AGB, we analyzed variables related to forest management, stand structure, topography, and climate. We developed linear (LM), generalized additive (GAM), and Random Forest (RF) empirical models to derive spatially explicit estimates and their uncertainty, and compared them. AGB was strongly influenced by forest management, as LiDAR-derived stand structure and stand age explained 80.9% to 89.8% of its spatial variability. The spatial heterogeneity of AGB varied positively with stand structural complexity and age in the managed forests. The type of predictive model had an impact on estimates of total AGB in our study site, which varied by as much as 19%. AGB densities varied from 0 to 492 ± 17 Mg ha−1 and the highest values were predicted by GAM. Uncertainty was not spatially homogeneously distributed and was higher with higher AGB values. Spatially explicit AGB estimates and their association with management and other variables in the study site can assist forest managers in planning thinning and harvesting schedules that would maximize carbon stocks on the landscape while continuing to provide timber and other ecosystem services. Our study represents an advancement toward the development of efficient strategies to spatially estimate AGB stocks and their uncertainty, as the GAM approach was used for the first time with improved results for such a purpose.
Collapse
|
8
|
Riveros-Iregui DA, Lorenzo TM, Liang LL, Hu J. Summer dry-down modulates the isotopic composition of soil CO2 production in snow-dominated landscapes. PLoS One 2018; 13:e0197471. [PMID: 29746589 PMCID: PMC5945025 DOI: 10.1371/journal.pone.0197471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Accepted: 05/02/2018] [Indexed: 11/23/2022] Open
Abstract
In mountainous landscapes, soil moisture is highly dynamic due to the effects of topography and the temporal variability imposed by seasonal precipitation, including rainfall and snow. Soil moisture is known to affect ecosystem carbon exchange both aboveground and belowground, as well as the stable isotopic composition of exchanged CO2. In this study we used an extensive suite of measurements to examine the effects of seasonal changes in soil moisture on the isotopic composition of soil CO2 production at the landscape level. We show that the seasonal decline in soil moisture (i.e., summer dry-down) appeared to impose a trend in the δ13C of soil CO2 production (δP) with more negative δP early in the growing season when soils were wet, and more positive δP as the growing season progressed and soils dried out. This seemingly generalizable pattern for a snow-dominated watershed is likely to represent the variability of recently assimilated C, tracked through the plant-soil system and imprinted in the respired CO2. Thus, our observations suggest that, at least for mountainous environments, seasonal changes in δP are largely mediated by soil moisture and their spatial variability is partially organized by topography.
Collapse
Affiliation(s)
- Diego A. Riveros-Iregui
- Department of Geography, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- * E-mail:
| | - Theresa M. Lorenzo
- School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
| | - Liyin L. Liang
- School of Science and Environmental Research Institute, University of Waikato, Hamilton, New Zealand
| | - Jia Hu
- School of Natural Resources and the Environment, University of Arizona, Tucson, Arizona, United States of America
| |
Collapse
|
9
|
Jucker T, Bongalov B, Burslem DFRP, Nilus R, Dalponte M, Lewis SL, Phillips OL, Qie L, Coomes DA. Topography shapes the structure, composition and function of tropical forest landscapes. Ecol Lett 2018; 21:989-1000. [PMID: 29659115 PMCID: PMC6849614 DOI: 10.1111/ele.12964] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 12/17/2017] [Accepted: 03/18/2018] [Indexed: 12/20/2022]
Abstract
Topography is a key driver of tropical forest structure and composition, as it constrains local nutrient and hydraulic conditions within which trees grow. Yet, we do not fully understand how changes in forest physiognomy driven by topography impact other emergent properties of forests, such as their aboveground carbon density (ACD). Working in Borneo – at a site where 70‐m‐tall forests in alluvial valleys rapidly transition to stunted heath forests on nutrient‐depleted dip slopes – we combined field data with airborne laser scanning and hyperspectral imaging to characterise how topography shapes the vertical structure, wood density, diversity and ACD of nearly 15 km2 of old‐growth forest. We found that subtle differences in elevation – which control soil chemistry and hydrology – profoundly influenced the structure, composition and diversity of the canopy. Capturing these processes was critical to explaining landscape‐scale heterogeneity in ACD, highlighting how emerging remote sensing technologies can provide new insights into long‐standing ecological questions.
Collapse
Affiliation(s)
- Tommaso Jucker
- Department of Plant Sciences, Forest Ecology and Conservation group, University of Cambridge, Cambridge, UK.,CSIRO Land and Water, 147 Underwood Avenue, Floreat, 6014, WA, Australia
| | - Boris Bongalov
- Department of Plant Sciences, Forest Ecology and Conservation group, University of Cambridge, Cambridge, UK
| | - David F R P Burslem
- School of Biological Sciences, University of Aberdeen, Cruickshank Building, St Machar Drive, Aberdeen, UK
| | - Reuben Nilus
- Sabah Forestry Department, Forest Research Centre, P.O. Box 1407, 90715, Sandakan, Sabah, Malaysia
| | - Michele Dalponte
- Department of Sustainable Agro-ecosystems and Bioresources, Research and Innovation Centre, Fondazione E. Mach, Via E. Mach 1, 38010, San Michele all'Adige, Italy
| | - Simon L Lewis
- School of Geography, University of Leeds, Leeds, LS2 9JT, UK
| | | | - Lan Qie
- School of Geography, University of Leeds, Leeds, LS2 9JT, UK.,Imperial College London, Silwood Park Campus, Buckhusrt Road, Ascot, SL5 7PY, UK
| | - David A Coomes
- Department of Plant Sciences, Forest Ecology and Conservation group, University of Cambridge, Cambridge, UK
| |
Collapse
|