The dangers of carbon-centric conservation for biodiversity

REDD (reduced Emissions from Deforestation and Degradation) has become the focus of many conservation efforts and is eating up lots of conservation money.  While REDD sounds good on paper, has many serious problems, most of which have been discussed at length elsewhere (e.g., HERE, HERE, HERE).  In collaboration with Alvaro Duque and colleagues, we have just published a new study highlighting one underappreciated problem with REDD and other carbon centric conservation schemes.  Basically, by adding value to high-biomass areas (such as lowland tropical forests, deforestation and degradation may be pushed to lower-biomass areas such as highland forests (i.e., leakage).  As we show in our analyses these low-biomass forests often contain high amounts of diversity and super high amounts of endemic diversity.  Importantly a lot of the diversity in these low-biomass forests is in life forms other than trees (e.g., fern, herbs, lianas, epiphytes…).  So even in schemes such as REDD+ where biodiversity is taken into consideration, low biomass forests may still be at risk since measures of biodiversity are usually based only on trees or other large charismatic species. The end result is that while carbon-centric approaches to conservation can potentially promote the protection of some habitats and thereby reduce net carbon emissions, they can potentially have the perverse effect of promoting deforestation in other habitats and thereby actually increase overall species extinction rates. The abstract of our paper, entitled “The dangers of carbon-centric conservation for biodiversity: a case study in the Andes,” is reproduced below and the original article is available through the journal Tropical Conservation Science HERE.

 

The dangers of carbon-centric conservation for biodiversity: a case study in the Andes
Alvaro Duque, Kenneth J. Feeley, Edersson Cabrera, Ricardo Callejas and Alvaro Idarraga

Carbon-centric conservation strategies such as the United Nation’s program to Reduce CO2 Emissions from Deforestation and Degradation (REDD+), are expected to simultaneously reduce net global CO2 emissions and mitigate species extinctions in regions with high endemism and diversity, such as the Tropical Andes Biodiversity Hotspot. Using data from the northern Andes, we show, however, that carbon-focused conservation strategies may potentially lead to increased risks of species extinctions if there is displacement (i.e., “leakage”) of land-use changes from forests with large aboveground biomass stocks but relatively poor species richness and low levels of endemism, to forests with lower biomass stocks but higher species richness and endemism, as are found in the Andean highlands (especially low-biomass non-tree growth forms such as herbs and epiphytes that are often overlooked in biological inventories). We conclude that despite the considerable potential benefits of REDD+ and other carbon-centric conservation strategies, there is still a need to develop mechanisms to safeguard against possible negative effects on biodiversity in situations where carbon stocks do not covary positively with species diversity and endemism.
.

Antioquia Colombia

 

Advertisements

Species Migrating Upslope Due to Climate Change in Tropical Montane Cloud Forests of Peru May Meet a Grass Ceiling

A recent piece from the Huffington Post discussing the work of UpWithClimate team member, Evan Rehm, is reproduced below.  The original article by Keith Peterman is available HERE.

 

recent letter by Evan Rehm in the Proceedings of the National Academy of Sciences (PNAS) respectfully challenges prior “spurious conclusions” by authors ofan earlier article hypothesizing that “tropical montane species are responding more strongly to climate change than temperate-zone species.” This scientific debate is not about climate change — scientists are in broad agreement that climate change is occurring. And, the debate is not about species redistribution — the IPCC foundwith “very high confidence” that species redistribution due to climate change is occurring on all continents and most oceans. The issue here is more subtle, but one of great importance for species survival.

Last August, I sat down with Evan at a Starbucks in York, Pa. to discuss his tropical research. Unshaven and a bit red-eyed, he had just returned from a two-year stint high in an Andean cloud forest of Peru. He was on a brief stop-over in York to visit family before return to his academic home in the Department of Biological Sciences at Florida International University.

2014-06-14-evanhuff1.jpg

Evan’s research interests broadly include species adaptations to climate change and environmental ecology. He conducts his primary research in the tropical montane cloud forests of Manύ National Park on the eastern slope of the Andes Mountains in Peru. Cloud forests are characterized by the presence of clouds or persistent mist — even in the dry season — and much precipitation comes in the form of “canopy drip” resulting from the condensation of fog or mist on tree leaves. A scant 1 percent of global woodlands are cloud forests, yet they are among the most biodiverse regions on Earth.

Working at the high-elevation treeline where closed-canopy cloud forest forests meets open alpine vegetation, Evan is trying to understand how these forests will adapt to climate change.

2014-06-14-evanhuff2tree.jpg

He explains how species are shifting ranges (migrating to new areas) in order to track the temperatures to which they are adapted — some species migrate toward the poles while others shift upslope to seek cool-temperature refuges.

He says, “The distances species have to travel based on temperature change are staggering.” Recent studies show that the rate of travel correlates closely with the rate of temperature change in a given region. Evan says, “It’s not just the temperature change. Man-made barriers such as deforestation, roads, and urban areas increase the distance [and therefore] decrease the speed at which species can migrate.” A good example is lowland Amazon rainforests which are especially vulnerable to climate change.

At higher elevation, “The treeline should be one of the first and most obvious shifts in ecological edges.” However, “Trees shift much slower than mobile organisms such as vertebrates.”

Evan states, “Species ability and speed of migration is particularly important in tropical montane cloud forests. Because biodiversity is extremely high, most species occur in narrow temperature ranges.” These narrow-niche species should react quickly to climate change by shifting upslope. However, if the treeline does not shift upslope with species occurring below the treeline, then the treeline may act as a barrier to upslope migrations of other species. “This creates elevated extinction risks in Andean tropical montane cloud forests.”

Fittingly, an article titled “Will Climate Change Imperil Your Cup of Starbucks?” appeared in National Geographic just three months after Evan and I shared our cup of Joe at the Starbucks in York. The author of this article chronicled his hike through the dense Andean cloud forest with Evan’s academic advisor Ken Feeley. Feeley stated, “There are known accounts that coffee as an agricultural product is moving up the slope with farmers planting it higher and higher. The cultivated coffee-growing areas in the lowlands are seeing decreased yields.” Of course, farmer’s planting at higher elevations is not the same as natural migration of trees. Feeley predicts significant species population reductions and extinctions due to climate change in the next 50 to 75 years based on his tree-migration studies in both Peru and Costa Rica.

During my own academic research visits to Costa Rica, I’ve encountered another climate change stress on coffee called “flora loca” (crazy flowers). I first observed flora loca in March 2010 while passing through small coffee plantations just beneath the Monteverde cloud forest. The scene of flower-covered coffee trees simply did not fit the season. For a northerner like me, it was something akin to a spray of fresh daffodils in frozen December soil. Diego Calderón, an agricultural management engineer, told me that these trees were actually on their third flora loca of the season, and that due to changing weather conditions in recent years, this mistimed blooming could be linked to climate change.

Getting back to the Pervian Andes cloud forest, Evan explains why the tropical montane treeline shift may not keep pace with climate change. Although “animals have the ability to move to new areas when their current location becomes climatically unsuitable… upslope shift of plants largely depends on seed dispersal” over multiple generations. Movement of the treeline may be further limited by narrow dispersal of seeds at the forest edge, low germination rate of seeds due to the harsh alpine microclimate, competition with established grasses, and even higher intensity UV solar radiation.

2014-06-14-evanhuff3grassland.jpg

In spite of the scientific debate concerning whether tropical montane species are or are not responding more strongly to climate change than temperate-zone species, one point is clear. The current upslope migration of tropical species due to climate change will encounter an ecological edge at the treeline which will challenge their very survival. Species will confront A Grass Ceiling — the alpine zone above the tropical montane cloud forest where they no longer have the ability to adapt.

By Keith Peterman