No abstract

We explore the issues relevant to those types of ecosystems containing new combinations of species that arise through human action, environmental change, and the impacts of the deliberate and inadvertent introduction of species from other regions. Novel ecosystems (also termed 'emerging ecosystems') result when species occur in combinations and relative abundances that have not occurred previously within a given biome. Key characteristics are novelty, in the form of new species combinations and the potential for changes in ecosystem functioning, and human agency, in that these ecosystems are the result of deliberate or inadvertent human action. As more of the Earth becomes transformed by human actions, novel ecosystems increase in importance, but are relatively little studied. Either the degradation or invasion of native or 'wild' ecosystems or the abandonment of intensively managed systems can result in the formation of these novel systems. Important considerations are whether these new systems are persistent and what values they may have. It is likely that it may be very difficult or costly to return such systems to their previous state, and hence consideration needs to be given to developing appropriate management goals and approaches.

Human pressures on the environment are changing spatially and temporally, with profound implications for the planet's biodiversity and human economies. Here we use recently available data on infrastructure, land cover and human access into natural areas to construct a globally standardized measure of the cumulative human footprint on the terrestrial environment at 1 km2 resolution from 1993 to 2009. We note that while the human population has increased by 23% and the world economy has grown 153%, the human footprint has increased by just 9%. Still, 75% the planet's land surface is experiencing measurable human pressures. Moreover, pressures are perversely intense, widespread and rapidly intensifying in places with high biodiversity. Encouragingly, we discover decreases in environmental pressures in the wealthiest countries and those with strong control of corruption. Clearly the human footprint on Earth is changing, yet there are still opportunities for conservation gains.

Remotely-sensed and bottom-up survey information were compiled on eight variables measuring the direct and indirect human pressures on the environment globally in 1993 and 2009. This represents not only the most current information of its type, but also the first temporally-consistent set of Human Footprint maps. Data on human pressures were acquired or developed for: 1) built environments, 2) population density, 3) electric infrastructure, 4) crop lands, 5) pasture lands, 6) roads, 7) railways, and 8) navigable waterways. Pressures were then overlaid to create the standardized Human Footprint maps for all non-Antarctic land areas. A validation analysis using scored pressures from 3114×1 km2 random sample plots revealed strong agreement with the Human Footprint maps. We anticipate that the Human Footprint maps will find a range of uses as proxies for human disturbance of natural systems. The updated maps should provide an increased understanding of the human pressures that drive macro-ecological patterns, as well as for tracking environmental change and informing conservation science and application.

International conservation planning at the end of the twentieth century is dominated by coarse-filter, supra-organismal approaches to conservation that may be insufficient to conserve certain species such as the jaguar ( Panthera onca ). If we are to retain broadly distributed species into the next century, we need to plan explicitly for their survival across their entire geographic range and through political boundaries while recognizing the variety of ecological roles the species plays in different habitats. In March 1999 the Wildlife Conservation Society sponsored a priority-setting and planning exercise for the jaguar across its range, from northern Mexico to northern Argentina. Field scientists from 18 countries reached consensus on four types of information: (1) the spatial extent of their jaguar knowledge, (2) the known, currently occupied range of jaguars, (3) areas with substantial jaguar populations, adequate habitat, and a stable and diverse prey base, and (4) point localities where jaguars have been observed during the last 10 years. During the exercise, these experts also conducted a range-wide assessment of the long-term survival prospects of the jaguar and developed an algorithm for prioritizing jaguar conservation units occurring in major habitat types. From this work, we learned that the known, occupied range of the jaguar has contracted to approximately 46% of estimates of its 1900 range. Jaguar status and distribution is unknown in another 12% of the jaguar's former range, including large areas in Mexico, Colombia, and Brazil. But over 70% of the area where jaguars are thought to still occur was rated as having a high probability of supporting their long-term survival. Fifty-one jaguar conservation units representing 30 different jaguar geographic regions were prioritized as the basis for a comprehensive jaguar conservation program. Planeación para Salvar una Especie: El Jaguar como ModeloResumen: La planeación de la conservación internacional al final del siglo veinte esta dominada por enfoques de grano grueso, supra-organísmicas que pueden ser insuficientes para conservar ciertas especies como el jaguar ( Panthera onca ). Si hemos de mantener especies ampliamente distribuidas en el próximo siglo, necesitamos planificar su supervivencia explícitamente en todo su rango geográfico a través de límites políticos al mismo tiempo que se reconozca la variedad de funciones ecológicas de las especies en diferentes hábitats. En marzo de 1999 la Sociedad de Conservación de Vida Silvestre promovió un ejercicio de definición de prioridades y de planeación para el jaguar en todo su rango de distribución, desde el norte de México hasta el norte de Argentina. Científicos de 18 países llegaron a consensos en cuatro tipos de información: (1) la extensión espacial de su conocimiento del jaguar, (2) el rango conocido, actualmente ocupado por el jaguar, (3) áreas con poblaciones importantes, hábitat adecuado y una base de presas estable y diversa y (4) localidades en las que se han observado jaguares durante los ú...