Dynamics of Carbon Accumulation in Tropical Dry Forests under Climate Change Extremes

We analyze here how much carbon is being accumulated annually by secondary tropical dry forests (TDFs) and how structure, composition, time since abandonment, and climate can influence the dynamics of forest carbon accumulation. The study was carried out in Santa Rosa National Park in Guanacaste province, Costa Rica and Mata Seca State Park in Minas Gerais, Brazil. Total carbon storage and carbon accumulation were obtained for both sites from the sum of the aboveground carbon and belowground carbon gain plus the annual litterfall. Carbon accumulation of these TDFs varied from 2.6 Mg C ha−1 y−1 to 6.3 Mg C ha−1 y−1, depending on the age of the forest stands. Time since abandonment and number of stems per plot were the best predictors for carbon storage, annual carbon gains, and losses. Mortality rates and carbon losses were also associated with seasonal climate variability. We found significant correlations between tree mortality, carbon losses and mean seasonal temperature, mean seasonal precipitation, potential evapotranspiration, and the Oceanic Niño Index. Carbon dynamics in tropical dry forests are driven by time since abandonment and forest structure; however, rising temperature and El Niño Southern Oscillation (ENSO) events can have a significant impact on tree mortality and carbon losses. Depending on their location and land-use history, some dry forests are more impacted by climatic extremes than others, and differences between secondary stages are expected.

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Spatial and temporal trends in carbon storage of peatlands of continental western Canada through the Holocene

Canadian Journal of Earth Sciences ◽

10.1139/e99-097 ◽

2000 ◽

Vol 37 (5) ◽

pp. 683-693 ◽

Cited By ~ 227

Author(s):

Dale H Vitt ◽

Linda A Halsey ◽

Ilka E Bauer ◽

Celina Campbell

Keyword(s):

Carbon Storage ◽

Carbon Sink ◽

Temporal Trends ◽

Carbon Accumulation ◽

Total Carbon ◽

Western Canada ◽

Biomass Carbon ◽

Above Ground Biomass ◽

Southern Limit ◽

Spatial And Temporal Trends

Peatlands of continental western Canada (Alberta, Saskatchewan, and Manitoba) cover 365 157 km2 and store 48.0 Pg of carbon representing 2.1% of the world's terrestrial carbon within 0.25% of the global landbase. Only a small amount, 0.10 Pg (0.2%) of this carbon, is currently stored in the above-ground biomass. Carbon storage in peatlands has changed significantly since deglaciation. Peatlands began to accumulate carbon around 9000 years ago in this region, after an initial deglacial lag. Carbon accumulation was climatically limited throughout much of continental western Canada by early Holocene maximum insolation. After 6000 BP, carbon accumulation increased significantly, with about half of current stores being reached by 4000 BP. Around 3000 BP carbon accumulation in continental western Canada began to slow as permafrost developed throughout the subarctic and boreal region and the current southern limit of peatlands was reached. Peatlands in continental western Canada continue to increase their total carbon storage today by 19.4 g m-2 year-1, indicating that regionally this ecosystem remains a large carbon sink.

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Resistance of African tropical forests to an extreme climate anomaly

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2003169118 ◽

2021 ◽

Vol 118 (21) ◽

pp. e2003169118

Author(s):

Amy C. Bennett ◽

Greta C. Dargie ◽

Aida Cuni-Sanchez ◽

John Tshibamba Mukendi ◽

Wannes Hubau ◽

...

Keyword(s):

Tropical Forests ◽

El Niño ◽

Tree Mortality ◽

El Nino ◽

Southern Oscillation ◽

Carbon Sink ◽

El Niño Event ◽

Dry Conditions ◽

Carbon Losses

The responses of tropical forests to environmental change are critical uncertainties in predicting the future impacts of climate change. The positive phase of the 2015–2016 El Niño Southern Oscillation resulted in unprecedented heat and low precipitation in the tropics with substantial impacts on the global carbon cycle. The role of African tropical forests is uncertain as their responses to short-term drought and temperature anomalies have yet to be determined using on-the-ground measurements. African tropical forests may be particularly sensitive because they exist in relatively dry conditions compared with Amazonian or Asian forests, or they may be more resistant because of an abundance of drought-adapted species. Here, we report responses of structurally intact old-growth lowland tropical forests inventoried within the African Tropical Rainforest Observatory Network (AfriTRON). We use 100 long-term inventory plots from six countries each measured at least twice prior to and once following the 2015–2016 El Niño event. These plots experienced the highest temperatures and driest conditions on record. The record temperature did not significantly reduce carbon gains from tree growth or significantly increase carbon losses from tree mortality, but the record drought did significantly decrease net carbon uptake. Overall, the long-term biomass increase of these forests was reduced due to the El Niño event, but these plots remained a live biomass carbon sink (0.51 ± 0.40 Mg C ha−1 y−1) despite extreme environmental conditions. Our analyses, while limited to African tropical forests, suggest they may be more resistant to climatic extremes than Amazonian and Asian forests.

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Effect of grazing and harvesting on diversity, recruitment and carbon accumulation of juvenile trees in tropical dry forests

Forest Ecology and Management ◽

10.1016/j.foreco.2012.07.053 ◽

2012 ◽

Vol 284 ◽

pp. 152-162 ◽

Cited By ~ 32

Author(s):

R.K. Chaturvedi ◽

A.S. Raghubanshi ◽

J.S. Singh

Keyword(s):

Carbon Accumulation ◽

Tropical Dry Forests ◽

Dry Forests

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Enhancing Ecosystem Function through Conservation: Threatened Plants Increase Local Carbon Storage in Tropical Dry Forests

Tropical Conservation Science ◽

10.1177/194008291500800410 ◽

2015 ◽

Vol 8 (4) ◽

pp. 999-1008 ◽

Cited By ~ 5

Author(s):

Juan C. Álvarez-Yépiz ◽

Martin Dovčiak

Keyword(s):

Carbon Storage ◽

Ecosystem Function ◽

Tropical Dry Forests ◽

Dry Forests ◽

Threatened Plants

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Evaluating carbon storage in restoration plantings in the Tasmanian Midlands, a highly modified agricultural landscape

The Rangeland Journal ◽

10.1071/rj15070 ◽

2015 ◽

Vol 37 (5) ◽

pp. 477 ◽

Cited By ~ 9

Author(s):

Lynda D. Prior ◽

Keryn I. Paul ◽

Neil J. Davidson ◽

Mark J. Hovenden ◽

Scott C. Nichols ◽

...

Keyword(s):

Carbon Storage ◽

Coarse Woody Debris ◽

Agricultural Landscape ◽

Woody Debris ◽

Carbon Stocks ◽

Carbon Accumulation ◽

Total Carbon ◽

Biomass Carbon ◽

Belowground Carbon ◽

Remnant Forest

In recent years there have been incentives to reforest cleared farmland in southern Australia to establish carbon sinks, but the rates of carbon sequestration by such plantings are uncertain at local scales. We used a chronosequence of 21 restoration plantings aged from 6 to 34 years old to measure how above- and belowground carbon relates to the age of the planting. We also compared the amount of carbon in these plantings with that in nearby remnant forest and in adjacent cleared pasture. In terms of total carbon storage in biomass, coarse woody debris and soil, young restoration plantings contained on average much less biomass carbon than the remnant forest (72 versus 203 Mg C ha–1), suggesting that restoration plantings had not yet attained maximum biomass carbon. Mean biomass carbon accumulation during the first 34 years after planting was estimated as 4.2 ± 0.6 Mg C ha–1 year–1, with the 10th and 90th quantile regression estimates being 2.1 and 8.8 Mg C ha–1 year–1. There were no significant differences in soil organic carbon (0–30-cm depth) between the plantings, remnant forest and pasture, with all values in the range of 59–67 Mg ha–1. This is in line with other studies showing that soil carbon is slow to respond to changes in land use. Based on our measured rates of biomass carbon accumulation, it would require ~50 years to accumulate the average carbon content of remnant forests. However, it is more realistic to assume the rates will slow with time, and it could take over 100 years to attain a new equilibrium of biomass carbon stocks.

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Blue carbon stocks in Baltic Sea eelgrass (<i>Zostera marina</i>) meadows

10.5194/bg-2016-131 ◽

2016 ◽

Cited By ~ 1

Author(s):

Maria Emilia Röhr ◽

Christoffer Boström ◽

Paula Canal-Vergés ◽

Marianne Holmer

Keyword(s):

Baltic Sea ◽

Carbon Storage ◽

Zostera Marina ◽

Carbon Stocks ◽

Blue Carbon ◽

Carbon Accumulation ◽

Total Carbon ◽

Sediment Surface ◽

Monetary Value ◽

Over The Top

Abstract. Although seagrasses cover only a minor fraction of the ocean seafloor, their carbon sink capacity account for nearly one-fifth of the oceanic carbon burial and thus play a critical structural and functional role in many coastal ecosystems. We sampled 10 eelgrass (Zostera marina) meadows in Finland and 10 in Denmark to explore the seagrass carbon stocks (Corg stock) and the carbon accumulation (Corg accumulation) in the Baltic Sea area. The study sites represent a gradient from sheltered to exposed locations in both regions to reflect expected minimum and maximum stocks and accumulation. The Corg stock integrated over the top 25 cm of the sediment averaged 627g C m−2 in Finland, while in Denmark the average Corg stock was over six times higher (4324 g C m−2). A conservative estimate of the total carbon pool in the regions ranged between 8.6–46.2 t ha−1. Our results suggest that the Finnish eelgrass meadows are minor carbon sinks compared to the Danish meadows, and that majority of the Corg produced in the Finnish meadows is exported. Similarly, the estimates for Corg accumulation in eelgrass meadows in Finland (< 0.002–0.033 t C y−1) were over two orders of magnitude lower compared to Denmark (0.376–3.636 Corg t y−1). Our analysis further showed that > 40 % of the variation in the Corg stocks was explained by sediment characteristics (density, porosity and silt content). In addition, the DistLm analysis showed, that root: shoot- ratio of Z. marina explained > 12 % and contribution of Z. marina detritus to the sediment surface Corg pool > 10 % of the variation in the Corg stocks, whereas annual eelgrass production explained additional 2.3 %. The mean monetary value for the present carbon storage and sequestration capacity of eelgrass meadows at Finland and Denmark, were 346 and 1862 € ha−1, respectively. We conclude that in order to produce reliable estimates on the magnitude of eelgrass Corg stocks, Corg accumulation and the monetary value of these services, more Blue Carbon studies investigating the role of sediment biogeochemistry, seascape structure, plant species architecture and hydrodynamic regime for seagrass carbon storage capacity are in urgent need.

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MODIS and PROBA-V NDVI Products Differ when Compared with Observations from Phenological Towers at Four Tropical Dry Forests in the Americas

Remote Sensing ◽

10.3390/rs11192316 ◽

2019 ◽

Vol 11 (19) ◽

pp. 2316 ◽

Cited By ~ 1

Author(s):

J. Antonio Guzmán Q. ◽

G. Arturo Sanchez-Azofeifa ◽

Mário M. Espírito-Santo

Keyword(s):

Vegetation Index ◽

Normalized Difference Vegetation Index ◽

Southern Oscillation ◽

Satellite Observations ◽

Tropical Dry Forests ◽

Vegetation Phenology ◽

Wet Season ◽

Dry Forests ◽

Near Surface ◽

Surface Observations

The Normalized Difference Vegetation Index (NDVI) is widely used to monitor vegetation phenology and productivity around the world. Over the last few decades, phenology monitoring at large scales has been possible due to the information and metrics derived from satellite sensors such as the Moderate Resolution Imaging Spectroradiometer (MODIS) or the Project for On-Board Autonomy–Vegetation (PROBA-V). However, due to their temporal and spatial resolution, adequate ground comparison is lacking. In this paper, we analyze how NDVI products from MODIS (Aqua and Terra) and PROBA-V predict vegetation phenology when compared with near-surface observations. We conduct this comparison at four tropical dry forests (TDFs) in the Americas. We undertake this study by comparing the following: (i) Dissimilarities of the standardized NDVI (NDVIS) using dynamic time warping, (ii) the differences of daily NDVIS between seasons and ENSO months using generalized linear models, and (iii) phenometrics derived from NDVI time series. Overall, our results suggest that NDVIS from satellite observations present DTW distances (dissimilarities) between 2.98 and 46.57 (18.91 ± 12.31) when compared with near-surface observations. Furthermore, NDVIS comparisons reveal that overall differences between satellite and near-surface observations are close to zero, but this tends to differ between seasons or when El Nino Southern Oscillation (ENSO) is present. Phenometrics comparisons show that metrics derived from satellite observations such as green-up, maturity, and start and end of the wet season strongly correlate with those from near-surface observations. In contrast, phenometrics that describe the day of the highest or lowest NDVI tend to be inconsistent with those from near-surface observations. All findings were observed independently of the NDVI source. Our results suggest that satellite-based NDVI products tend to be inconsistent descriptors of vegetation events on tropical deciduous forests in comparison with near-surface observations. These results reinforce the idea that satellite-based NDVI products should be used and interpreted with great caution and only in ecosystems with well-established knowledge of their vegetation phenology.

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