Shaun C Cunningham | Deakin University (original) (raw)
Uploads
Papers by Shaun C Cunningham
Global Change Biology, 2012
Bookmarks Related papers MentionsView impact
Journal of Applied Ecology, 2015
Bookmarks Related papers MentionsView impact
Nature Climate Change, 2015
Bookmarks Related papers MentionsView impact
Land Use Policy, 2016
tReforestation will have important consequences for the global challenges of mitigating climate c... more tReforestation will have important consequences for the global challenges of mitigating climate change,arresting habitat decline and ensuring food security. We examined field-scale trade-offs between carbonsequestration of tree plantings and biodiversity potential and loss of agricultural land. Extensive surveysof reforestation across temperate and tropical Australia (N = 1491 plantings) were used to determine howplanting width and species mix affect carbon sequestration during early development (< 15 year). Carbonaccumulation per area increased significantly with decreasing planting width and with increasing pro-portion of eucalypts (the predominant over-storey genus). Highest biodiversity potential was achievedthrough block plantings (width > 40 m) with about 25% of planted individuals being eucalypts. Carbon andbiodiversity goals were balanced in mixed-species plantings by establishing narrow belts (width < 20 m)with a high proportion (>75%) of eucalypts, and in monocultures of mallee eucalypt plantings by using thewidest belts (ca. 6–20 m). Impacts on agriculture were minimized by planting narrow belts (ca. 4 m) ofmallee eucalypt monocultures, which had the highest carbon sequestering efficiency. A plausible scenariowhere only 5% of highly-cleared areas (<30% native vegetation cover remaining) of temperate Australiaare reforested showed substantial mitigation potential. Total carbon sequestration after 15 years was upto 25 Mt CO2-e year−1when carbon and biodiversity goals were balanced and 13 Mt CO2-e year−1if blockplantings of highest biodiversity potential were established. Even when reforestation was restricted tomarginal agricultural land (<$2000 ha−1land value, 28% of the land under agriculture in Australia), totalmitigation potential after 15 years was 17–26 Mt CO2-e year−1using narrow belts of mallee plantings. Thiswork provides guidance on land use to governments and planners. We show that the multiple benefitsof young tree plantings can be balanced by manipulating planting width and species choice at establish-ment. In highly-cleared areas, such plantings can sequester substantial biomass carbon while improvingbiodiversity and causing negligible loss of agricultural land.
Bookmarks Related papers MentionsView impact
Land Degradation & Development, 2015
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Forest Ecology and Management, 2015
Bookmarks Related papers MentionsView impact
Global Ecology and Biogeography, Feb 1, 2014
ABSTRACT AimWe used models of remotely sensed estimates of forest-stand condition (degree of die-... more ABSTRACT AimWe used models of remotely sensed estimates of forest-stand condition (degree of die-back) with models of avian responses to stand condition to determine how the avifauna responded to a 13-year drought, and how the avifauna might respond to a predicted much warmer and drier climate in the next 60 years. LocationFloodplain forests of the southern Murray-Darling Basin, Australia. Methods We selected 45 2-ha locations that spanned the full range of stand condition and conducted bird surveys and rapid assessments of breeding, which involved repeated measurements over the breeding season. These values were modelled as functions of stand condition and several other on-site predictors. We made hindcast estimates of the proportions of forest in different stand-condition classes. We developed a trajectory of change in these proportions under the regionally downscaled estimates of climate change under the A1F1 IPCC emission scenario, which were linked with patterns of change in drier, hotter extant forests. The hindcast and projected values were coupled with the results of the statistical models for the avifauna to provide future projections for the avifauna. ResultsThree avifaunal variables (measures of abundance, effective species richness and total breeding score summed for all species) were strongly related to stand condition. Hindcast estimates based on the assumption of original good condition suggested that the response variables had declined by >25% since 1750. Projected declines in the response variables from 2009 to 2070 were >29%, while differences between 1750 and 2070 were >58%. Conclusions Stand condition strongly influences birds, so that reliable estimates of avifaunal change can be made by using remotely sensed estimates of stand condition. Given probable changes in forest condition under climate change, we project that the prospects for these avifauna are dire under the A1F1 or more extreme emission scenarios.
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Journal of Animal Ecology, 2015
Bookmarks Related papers MentionsView impact
Annals of botany, 2013
Root length and depth determine capture of water and nutrients by plants, and are targets for cro... more Root length and depth determine capture of water and nutrients by plants, and are targets for crop improvement. Here we assess a controlled-environment wheat seedling screen to determine speed, repeatability and relatedness to performance of young and adult plants in the field. Recombinant inbred lines (RILs) and diverse genotypes were grown in rolled, moist germination paper in growth cabinets, and primary root number and length were measured when leaf 1 or 2 were fully expanded. For comparison, plants were grown in the field and root systems were harvested at the two-leaf stage with either a shovel or a soil core. From about the four-leaf stage, roots were extracted with a steel coring tube only, placed directly over the plant and pushed to the required depth with a hydraulic ram attached to a tractor. In growth cabinets, repeatability was greatest (r = 0.8, P < 0.01) when the paper was maintained moist and seed weight, pathogens and germination times were controlled. Scanned t...
Bookmarks Related papers MentionsView impact
Water Resources Research, 2011
Human actions are engendering severe stresses on forests and their biotaFlow-on effects of water ... more Human actions are engendering severe stresses on forests and their biotaFlow-on effects of water harvesting is the prominent stressorEffects of direct human actions are exacerbated by climate change
Bookmarks Related papers MentionsView impact
ABSTRACT Background/Question/Methods Tropical rainforests, which are already restricted and degra... more ABSTRACT Background/Question/Methods Tropical rainforests, which are already restricted and degraded by human activities like many ecosystems, are likely to be further threatened by the rising temperatures anticipated with climate change. Prediction of changes to plant distributions under rising temperatures has involved models based on temperature tolerances estimated from either native distributions or leaf-level physiology. Australian rainforests provide a unique opportunity to investigate the responses of plants to temperature within the same forest type, as they cover a wide range of climates from cool temperate to tropical. We sought to determine if there were consistent differences in the physiology of temperate and tropical rainforest trees that could explain their contrasting climatic distributions. We studied eight evergreen rainforest tree species, from different families, across a 33o latitudinal gradient, with an associated range in mean annual temperature of 9 to 23oC. Physiological responses to temperature were measured in seedlings grown in controlled environments under a range of contrasting temperatures. Results/Conclusions Leaves of tropical species were found to reach maximum rates of photosynthesis when developed under higher temperatures than temperate species. More importantly, tropical species maintained high photosynthetic rates over a narrower range of developmental temperatures. Similarly, when fully-expanded leaves were exposed to new growth temperatures, tropical species maintained high photosynthetic rates over a narrower range of temperatures than temperate species. Although temperate species showed maximum growth at lower temperatures than tropical species, these temperatures were 8oC higher than would be predicted from their maxima for photosynthesis and native climates. This discrepancy between photosynthesis and whole plant growth in the temperate species was not explained by changes in biomass allocation. Leaves of the tropical species were more heat tolerant and less frost tolerant than leaves of the temperate species, which is consistent with their climate distributions. In contrast, the temperature tolerance of the photosynthetic apparatus was unrelated to climate in a species’ native habitat. In conclusion, rainforest tree species of Australia showed several physiological differences that were consistent with their native distributions. The narrower temperature tolerance of photosynthesis in the tropical species suggests they will be more susceptible to predicted future temperature increases than temperate species. However, photosynthetic responses did not scale up to whole-plant growth, suggesting that photosynthetic responses cannot be used in isolation to predict present and future distribution of rainforest species.
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
PLoS ONE, 2014
Bookmarks Related papers MentionsView impact
Global Ecology and Biogeography, 2013
Bookmarks Related papers MentionsView impact
Global Change Biology, 2012
Bookmarks Related papers MentionsView impact
Journal of Applied Ecology, 2015
Bookmarks Related papers MentionsView impact
Nature Climate Change, 2015
Bookmarks Related papers MentionsView impact
Land Use Policy, 2016
tReforestation will have important consequences for the global challenges of mitigating climate c... more tReforestation will have important consequences for the global challenges of mitigating climate change,arresting habitat decline and ensuring food security. We examined field-scale trade-offs between carbonsequestration of tree plantings and biodiversity potential and loss of agricultural land. Extensive surveysof reforestation across temperate and tropical Australia (N = 1491 plantings) were used to determine howplanting width and species mix affect carbon sequestration during early development (< 15 year). Carbonaccumulation per area increased significantly with decreasing planting width and with increasing pro-portion of eucalypts (the predominant over-storey genus). Highest biodiversity potential was achievedthrough block plantings (width > 40 m) with about 25% of planted individuals being eucalypts. Carbon andbiodiversity goals were balanced in mixed-species plantings by establishing narrow belts (width < 20 m)with a high proportion (>75%) of eucalypts, and in monocultures of mallee eucalypt plantings by using thewidest belts (ca. 6–20 m). Impacts on agriculture were minimized by planting narrow belts (ca. 4 m) ofmallee eucalypt monocultures, which had the highest carbon sequestering efficiency. A plausible scenariowhere only 5% of highly-cleared areas (<30% native vegetation cover remaining) of temperate Australiaare reforested showed substantial mitigation potential. Total carbon sequestration after 15 years was upto 25 Mt CO2-e year−1when carbon and biodiversity goals were balanced and 13 Mt CO2-e year−1if blockplantings of highest biodiversity potential were established. Even when reforestation was restricted tomarginal agricultural land (<$2000 ha−1land value, 28% of the land under agriculture in Australia), totalmitigation potential after 15 years was 17–26 Mt CO2-e year−1using narrow belts of mallee plantings. Thiswork provides guidance on land use to governments and planners. We show that the multiple benefitsof young tree plantings can be balanced by manipulating planting width and species choice at establish-ment. In highly-cleared areas, such plantings can sequester substantial biomass carbon while improvingbiodiversity and causing negligible loss of agricultural land.
Bookmarks Related papers MentionsView impact
Land Degradation & Development, 2015
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Forest Ecology and Management, 2015
Bookmarks Related papers MentionsView impact
Global Ecology and Biogeography, Feb 1, 2014
ABSTRACT AimWe used models of remotely sensed estimates of forest-stand condition (degree of die-... more ABSTRACT AimWe used models of remotely sensed estimates of forest-stand condition (degree of die-back) with models of avian responses to stand condition to determine how the avifauna responded to a 13-year drought, and how the avifauna might respond to a predicted much warmer and drier climate in the next 60 years. LocationFloodplain forests of the southern Murray-Darling Basin, Australia. Methods We selected 45 2-ha locations that spanned the full range of stand condition and conducted bird surveys and rapid assessments of breeding, which involved repeated measurements over the breeding season. These values were modelled as functions of stand condition and several other on-site predictors. We made hindcast estimates of the proportions of forest in different stand-condition classes. We developed a trajectory of change in these proportions under the regionally downscaled estimates of climate change under the A1F1 IPCC emission scenario, which were linked with patterns of change in drier, hotter extant forests. The hindcast and projected values were coupled with the results of the statistical models for the avifauna to provide future projections for the avifauna. ResultsThree avifaunal variables (measures of abundance, effective species richness and total breeding score summed for all species) were strongly related to stand condition. Hindcast estimates based on the assumption of original good condition suggested that the response variables had declined by >25% since 1750. Projected declines in the response variables from 2009 to 2070 were >29%, while differences between 1750 and 2070 were >58%. Conclusions Stand condition strongly influences birds, so that reliable estimates of avifaunal change can be made by using remotely sensed estimates of stand condition. Given probable changes in forest condition under climate change, we project that the prospects for these avifauna are dire under the A1F1 or more extreme emission scenarios.
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Journal of Animal Ecology, 2015
Bookmarks Related papers MentionsView impact
Annals of botany, 2013
Root length and depth determine capture of water and nutrients by plants, and are targets for cro... more Root length and depth determine capture of water and nutrients by plants, and are targets for crop improvement. Here we assess a controlled-environment wheat seedling screen to determine speed, repeatability and relatedness to performance of young and adult plants in the field. Recombinant inbred lines (RILs) and diverse genotypes were grown in rolled, moist germination paper in growth cabinets, and primary root number and length were measured when leaf 1 or 2 were fully expanded. For comparison, plants were grown in the field and root systems were harvested at the two-leaf stage with either a shovel or a soil core. From about the four-leaf stage, roots were extracted with a steel coring tube only, placed directly over the plant and pushed to the required depth with a hydraulic ram attached to a tractor. In growth cabinets, repeatability was greatest (r = 0.8, P < 0.01) when the paper was maintained moist and seed weight, pathogens and germination times were controlled. Scanned t...
Bookmarks Related papers MentionsView impact
Water Resources Research, 2011
Human actions are engendering severe stresses on forests and their biotaFlow-on effects of water ... more Human actions are engendering severe stresses on forests and their biotaFlow-on effects of water harvesting is the prominent stressorEffects of direct human actions are exacerbated by climate change
Bookmarks Related papers MentionsView impact
ABSTRACT Background/Question/Methods Tropical rainforests, which are already restricted and degra... more ABSTRACT Background/Question/Methods Tropical rainforests, which are already restricted and degraded by human activities like many ecosystems, are likely to be further threatened by the rising temperatures anticipated with climate change. Prediction of changes to plant distributions under rising temperatures has involved models based on temperature tolerances estimated from either native distributions or leaf-level physiology. Australian rainforests provide a unique opportunity to investigate the responses of plants to temperature within the same forest type, as they cover a wide range of climates from cool temperate to tropical. We sought to determine if there were consistent differences in the physiology of temperate and tropical rainforest trees that could explain their contrasting climatic distributions. We studied eight evergreen rainforest tree species, from different families, across a 33o latitudinal gradient, with an associated range in mean annual temperature of 9 to 23oC. Physiological responses to temperature were measured in seedlings grown in controlled environments under a range of contrasting temperatures. Results/Conclusions Leaves of tropical species were found to reach maximum rates of photosynthesis when developed under higher temperatures than temperate species. More importantly, tropical species maintained high photosynthetic rates over a narrower range of developmental temperatures. Similarly, when fully-expanded leaves were exposed to new growth temperatures, tropical species maintained high photosynthetic rates over a narrower range of temperatures than temperate species. Although temperate species showed maximum growth at lower temperatures than tropical species, these temperatures were 8oC higher than would be predicted from their maxima for photosynthesis and native climates. This discrepancy between photosynthesis and whole plant growth in the temperate species was not explained by changes in biomass allocation. Leaves of the tropical species were more heat tolerant and less frost tolerant than leaves of the temperate species, which is consistent with their climate distributions. In contrast, the temperature tolerance of the photosynthetic apparatus was unrelated to climate in a species’ native habitat. In conclusion, rainforest tree species of Australia showed several physiological differences that were consistent with their native distributions. The narrower temperature tolerance of photosynthesis in the tropical species suggests they will be more susceptible to predicted future temperature increases than temperate species. However, photosynthetic responses did not scale up to whole-plant growth, suggesting that photosynthetic responses cannot be used in isolation to predict present and future distribution of rainforest species.
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
PLoS ONE, 2014
Bookmarks Related papers MentionsView impact
Global Ecology and Biogeography, 2013
Bookmarks Related papers MentionsView impact