![]() ![]() In coming decades, climate changes are expected to produce major shifts in vegetation distributions at unprecedented rates, in large part due to mortality ( 14) however, largely because of the lack of field data on vegetation mortality, current models do not represent adequately such rapid effects ( 14, 15). Moreover, most field studies and model-based assessments of vegetation responses to climate have focused on changes associated with natality and growth, which are inherently slow processes for woody plants-even though the most rapid changes in vegetation are caused by mortality rather than natality ( 13). Previous studies of woody ecotones document landscape-scale shifts in vegetation as occurring only over relatively long (decades to millennia) periods ( 8– 12). Persistent vegetation shifts are most clearly detected in the distributions and abundances of long-lived woody plants, namely, trees and shrubs ( 7). The responses of vegetation to variations in climate are expected to be most rapid and extreme at ecotones, the boundaries between ecosystems ( 2– 5), with semiarid ecotones considered to be among the most sensitive ( 6). The rapidity and the complex dynamics of the persistent shift point to the need to represent more accurately these dynamics, especially the mortality factor, in assessments of the effects of climate change.ĭistributions of vegetation across landscapes depend on climate, perhaps best illustrated by the wholesale movement of plant species across geographic and topographic gradients during the last deglaciation ( 1). Forest patches within the shift zone became much more fragmented, and soil erosion greatly accelerated. Here we report the most rapid landscape-scale shift of a woody ecotone ever documented: in northern New Mexico in the 1950s, the ecotone between semiarid ponderosa pine forest and piñon–juniper woodland shifted extensively (2 km or more) and rapidly (<5 years) through mortality of ponderosa pines in response to a severe drought. However, current models do not adequately provide for such rapid effects-particularly those caused by mortality-largely because of the lack of data from field studies. These shifts are expected to be most rapid and extreme at ecotones, the boundaries between ecosystems, particularly those in semiarid landscapes. Circularity also includes product lifetime longer lifetime reduces the resource consumption and transportation emissions associated with the introduction of new products.In coming decades, global climate changes are expected to produce large shifts in vegetation distributions at unprecedented rates. Upgrading, serviceability, refurbishment, spare parts harvesting, increased recycled content and recyclability, weight reduction, selection of more sustainable materials – these all help to reduce resource consumption. It is calculated by assessing environmental performance over multiple life cycles, taking into account, for example, the recovery of materials and their reuse in new products. At the same time, designing packaging to be reusable, recyclable or compostable also ensures it is circular economy-ready.Ĭircularity refers to the potential of a system, product or component to contribute to the circular economy. from recycled and/or certified renewable sources, 100% recyclable, easily separable), helps minimize resource consumption and environmental impact over the life cycle of the packaging. Material, weight and volume reduction, along with smart material choices (e.g. By minimizing or eliminating the use of hazardous substances, we can reduce our products’ health and/or environmental impact. Products are made using a range of substances, some of which may have an impact on people’s health or the environment. By improving the energy efficiency of a product, we can reduce its energy consumption and carbon footprint. Energy consumption is often the single most important factor in determining a product’s lifecycle environmental impact.
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