Landscape Partnership Resources Library
The Greening of Synfuels
An old, dirty technology to make transportation fuels from coal could fight global warming, say proponents. The trick is using more biomass and burying the carbon dioxide that’s generated 18 APRIL 2008 VOL 320 SCIENCE
How Does Climate Change Affect Biodiversity?
The most recent and complex bioclimate models excel at describing species’ current distributions. Yet, it is unclear which models will best predict how climate change will affect their future distributions. 8 SEPTEMBER 2006 VOL 313 SCIENCE
Not All About Consumption
Resource exploitation can lead to increased ecological impacts even when overall consumption levels stay the same 15 March 2013 VOL 339 SCIENCE
Freshwater Methane Emissions Offset the Continental Carbon Sink
Acornerstone of our understanding of the contemporary global carbon cycle is that the terrestrial land surface is an important greenhouse gas (GHG) sink (1, 2). The global land sink is estimated to be 2.6 T 1.7 Pg of C year−1 (variability T range, excluding C emissions because of deforestation) (1). Lakes, impoundments, and rivers are parts of the terrestrial landscape, but they have not yet been included in the terrestrial GHG balance (3, 4). Available data suggest, however, that freshwaters can be substantial sources of CO2 (3, 5) and CH4 (6). Over time, soil carbon reaches freshwaters by lateral hydrological transport, where it can meet several fates, including burial in sediments, further transport to the sea, or evasion to the atmosphere as CO2 or CH4 (7). CH4 emissions may be small in terms of carbon, but CH4 is a more potent GHG than CO2 over century time scales. This study indicates that global CH4 emissions expressed as CO2 equivalents correspond to at least 25% of the estimated terrestrial GHG sink.
Status and Ecological Effects of the World’s Largest Carnivores
The largest terrestrial species in the order Carnivora are wide-ranging and rare because of their positions at the top of food webs. They are some of the world’s most admired mammals and, ironically, some of the most imperiled. Most have experienced substantial population declines and range contractions throughout the world during the past two centuries. Because of the high metabolic demands that come with endothermy and large body size, these carnivores often require large prey and expansive habitats. These food requirements and wide-ranging behavior often bring them into confl ict with humans and livestock. This, in addition to human intolerance, renders them vulnerable to extinction. Large carnivores face enormous threats that have caused massive declines in their populations and geographic ranges, including habitat loss and degradation, persecution, utilization, and depletion of prey. We highlight how these threats can affect the conservation status and ecological roles of this planet’s 31 largest carnivores.
From Past to Future Warming
Analyses of past observations help to predict the human contribution to future climate change. 21 FEBRUARY 2014 VOL 343 SCIENCE
Wildlife decline and social conflict
Policies aimed at reducing wildlife-related conflict must address the underlying causes
The Global Plight of Pollinators
Wild pollinators are in decline, and managed honeybees cannot compensate for their loss. 29 MARCH 2013 VOL 339 SCIENCE
Marine Taxa Track Local Climate Velocities
Organisms are expected to adapt or move in response to climate change, but observed distribution shifts span a wide range of directions and rates. Explanations often emphasize biological distinctions among species, but general mechanisms have been elusive. We tested an alternative hypothesis: that differences in climate velocity—the rate and direction that climate shifts across the landscape—can explain observed species shifts. We compiled a database of coastal surveys around North America from 1968 to 2011, sampling 128 million individuals across 360 marine taxa. Climate velocity explained the magnitude and direction of shifts in latitude and depth much more effectively than did species characteristics. Our results demonstrate that marine species shift at different rates and directions because they closely track the complex mosaic of local climate velocities. SCIENCE VOL 341 13 SEPTEMBER 2013
Is Embracing Change Our Best Bet?
Restoration ecology and conservation biology are both under pressure to adapt to accelerated anthropogenic global change. Pristine areas free from human infl uence no longer exist and, arguably, have not for thousands of years ( 1). Major landcover transformations for agriculture affected vast territories more than 3000 years ago ( 2). Large mammal extinctions in the late Pleistocene (circa 12,000 years ago) were related to human expansion ( 3). And relocation of nowwidespread naturalized species was already happening 4230 years ago, when domestic dogs (dingos) were introduced into Australia by way of southeast Asia ( 4). Thus, humansculpted landscapes are what we have been mostly managing for millennia. Because the rate of alteration has dramatically increased over the past 200 years, those ancient localized impacts now affect most of the world. Additionally, other indirect impacts act at a planetary scale—e.g., increased carbon dioxide concentration and nitrogen deposition
Pathways for Conservation
NEXT WEEK, CONSERVATION SCIENTISTS WILL GATHER AT THE INTERNATIONAL CONGRESS FOR Conservation Biology (ICCB) in Baltimore, Maryland, to grapple with the challenges of preserving our natural world in the face of a growing and increasingly consumptive human population. The natural world provides countless services, such as clean water, protection from fl ooding, and carbon sequestration, while offering opportunities for new medicines, foods, and energy production. Yet these valuable services and opportunities are disappearing along with the species and natural areas that supply them. The needs of a growing human population must be met while conserving the planet’s natural systems. Accomplishing both will depend on making clearer connections between scientifi c results regarding issues such as biodiversity loss and the critical decisions that must be made about conditions that underlie change, such as greenhouse gas emissions and freshwater availability. The good news is that today’s conservation scientists are developing innovative tools and strategies. SCIENCE VOL 341
Water in the Balance
Satellite data may enable improved management of regional groundwater reserves. VOL 340 SCIENCE
Physical Laws Shape Biology
IN THE PERSPECTIVE “A DYNAMICAL-SYSTEMS VIEW OF STEM CELL biology” (12 October 2012, p. 215), C. Furusawa and K. Kaneko discuss the relevance of dynamic systems biology approaches and the concept of “attractors” to understand cell differentiation and proliferation. We share their excitement in using computational models that apply physical laws to cell fate decision.
What Does Zero Deforestation Mean?
Ambiguous defi nitions and metrics create risks for forest conservation and accountability. SCIENCE VOL 342
Old Trees: Extraction, Conservation Can Coexist
BECAUSE LARGE OLD TREES ARE ESSENTIAL FOR FOREST ECOSYSTEM INTEGRITY AND BIODIVERsity, timber extraction in managed forests should preferentially be concentrated where large old trees are least likely to develop (“Global decline in large old trees,” D. B. Lindenmayer et al., Perspectives, 7 December 2012, p. 1305). However, timber extraction and the conservation of large old trees are not necessarily mutually exclusive. Current forest policy and management practices in Flanders, Belgium, aim to convert even-aged stands (areas in which trees are all the same age) to stands with trees of varying ages in an effort to increase forest ecosystem stability and resilience and to allow trees to grow old. As part of their ecologically sustainable forest management, public forest managers have adopted a large-tree retention approach [see also (1, 2)]. Tree islands within stands managed for production of high-quality timber are reserved for conservation, and trees within these islands will never be extracted. Large old trees of commercially valuable species that have grown beyond the commercially optimal dimensions will not be logged either. And no tree beyond a threshold diameter [currently set at dbh (diameter at breast height) of more than 102 cm] will ever be logged. The strip-shelterwood system (in which trees are cut in linear strips and surrounding trees are given time to grow old) and the coppice-with-standards system (in which some trees are left to grow while others around them are cut) are two examples of forest management that allows the combination of sustainable forest exploitation and conservation of large old trees
Simultaneously Mitigating Near-Term Climate Change and Improving Human Health and Food Security
Tropospheric ozone and black carbon (BC) contribute to both degraded air quality and global warming. We considered ~400 emission control measures to reduce these pollutants by using current technology and experience. We identified 14 measures targeting methane and BC emissions that reduce projected global mean warming ~0.5°C by 2050. This strategy avoids 0.7 to 4.7 million annual premature deaths from outdoor air pollution and increases annual crop yields by 30 to 135 million metric tons due to ozone reductions in 2030 and beyond. Benefits of methane emissions reductions are valued at $700 to $5000 per metric ton, which is well above typical marginal abatement costs (less than $250). The selected controls target different sources and influence climate on shorter time scales than those of carbon dioxide–reduction measures. Implementing both substantially reduces the risks of crossing the 2°C threshold.
Financial Costs of Meeting Global Biodiversity Conservation Targets: Current Spending and Unmet Needs
World governments have committed to halting human-induced extinctions and safeguarding important sites for biodiversity by 2020, but the financial costs of meeting these targets are largely unknown. We estimate the cost of reducing the extinction risk of all globally threatened bird species (by ≥1 International Union for Conservation of Nature Red List category) to be U.S. $0.875 to $1.23 billion annually over the next decade, of which 12% is currently funded. Incorporating threatened nonavian species increases this total to U.S. $3.41 to $4.76 billion annually. We estimate that protecting and effectively managing all terrestrial sites of global avian conservation significance (11,731 Important Bird Areas) would cost U.S. $65.1 billion annually. Adding sites for other taxa increases this to U.S. $76.1 billion annually. Meeting these targets will require conservation funding to increase by at least an order of magnitude.
Plant Species Richness and Ecosystem Multifunctionality in Global Drylands
Experiments suggest that biodiversity enhances the ability of ecosystems to maintain multiple functions, such as carbon storage, productivity, and the buildup of nutrient pools (multifunctionality). However, the relationship between biodiversity and multifunctionality has never been assessed globally in natural ecosystems. We report here on a global empirical study relating plant species richness and abiotic factors to multifunctionality in drylands, which collectively cover 41% of Earth’s land surface and support over 38% of the human population. Multifunctionality was positively and significantly related to species richness. The best-fitting models accounted for over 55% of the variation in multifunctionality and always included species richness as a predictor variable. Our results suggest that the preservation of plant biodiversity is crucial to buffer negative effects of climate change and desertification in drylands.
The Greenhouse Is Making the Water-Poor Even Poorer
How bad will global warming get? The question has long been cast in terms of how hot the world will get. But perhaps more important to the planet’s inhabitants will be how much rising greenhouse gases crank up the water cycle. Theory and models predict that a strengthening greenhouse will increase precipitation where it is already relatively high—tropical rain forests, for example— and decrease it where it is already low, as in the subtropics. SCIENCE VOL 336 27 APRIL 2012
Ocean Salinities Reveal Strong Global Water Cycle Intensification During 1950 to 2000
Fundamental thermodynamics and climate models suggest that dry regions will become drier and wet regions will become wetter in response to warming. Efforts to detect this long-term response in sparse surface observations of rainfall and evaporation remain ambiguous. We show that ocean salinity patterns express an identifiable fingerprint of an intensifying water cycle. Our 50-year observed global surface salinity changes, combined with changes from global climate models, present robust evidence of an intensified global water cycle at a rate of 8 T 5% per degree of surface warming. This rate is double the response projected by current-generation climate models and suggests that a substantial (16 to 24%) intensification of the global water cycle will occur in a future 2° to 3° warmer world. SCIENCE VOL 336
