LECTURE18 Human Disruption and Ecological Restoration seful measure of Nutrient retention: Although all ecosystems are open to nutrient fluxes, some are more open than others Species Interaction Biotic interactions Reassembly of formerly associated plant populations often-but not always- leads to reconstruction of the entire community Species Interaction There are fundamental of ecolog ical questions, illustrating the profound contr ibution restoration ecology could make to ecological science;some of these questions are does increasing the species diversity of a community increase its stability and resilience? how does genetic diversity within component species influence the stability of an ecological community? Species Interaction if species evolve together, do they tend to mpatible or less so how does the age structure of component species an ecological community? Etc Species Interaction In all operations, whatever the endpoint, the following are important considerations: (1)speed of attainment; (2)cheapness, ()reliability in attainment; and (4)stability In doing restoration: There are a number of ideas and steps Nutrient addition Treating toxicities Adding species In doing restoration Soil replacement simply disregard its individual problems and import a new soil surface, on which a new ecosystem can quickly be established. In a crude sense, this may require little understanding of what is wrong with the site restoration: Direct treatment: in many situations, however, soil cannot be imported or replaced, and the material existing on a site has to be treated direc tly to achieve restoration In doing restoration de to loosen subsoil and topsoil by ripping the substrate to depths up to I meter. This is then followed by sha llower cultivations, to about 20 cm. Finally, the soil surface is carefully prepared to provide a good seedbed, and a favorable season is chosen for sowing. In doing restoration: Nutrient addition after all the above problems, there is obviously the need for nutrients Treating toxicities Adding species In doing restoratio Ecological restoration is now being recognized as an important tool that can produce add itional improvements in the quality of our resources to support diverse, productive communities of plants and animals that provide significant ecological and social benefits In doing restoration Restoration ists use the best ecological science avail able to understand and reverse the sources of damage, restor ing the diverse native plant and animal communities, reinstating natural disturbance regimes such as light sur face fires, and developing harmonious relationships between cople and the land Why can't we just let nature take its course? More than a century of severe habitat alteration has changed our forests and ecosystems to such an extent that they can no longer eal themselves Why can't we just let nature take its course? The goals of ecological restoration are to approximate natural ecosystem structure(plant and animal compositions and patterns)and es(e.g. disturbance regimes such as fire, nutrient cycling, and productivity )that were characteristic of the system before disturbance Why can't we just let nature take its course? These natural ecosystem structures and processes are critical for maintain ing an ecologically sustainable forest and restoring the diversity of wildlife and plants that depend on it.LECTURE18 Human Disruption and Ecological Restoration 2 Productivity; is dependent upon efficacy. A restored community should be as productive as the original. This is a useful measure of community performance as it integrates many processes; including photosynthesis, respiration, herbivory, and death. Species Interaction Nutrient retention; Although all ecosystems are open to nutrient fluxes, some are more open than others. Species Interaction Biotic interactions; Reassembly of formerly associated plant populations often – but not always – leads to reconstruction of the entire community. Species Interaction There are fundamental of ecological questions, illustrating the profound contribution restoration ecology could make to ecological science; some of these questions are: Species Interaction does increasing the species diversity of a community increase its stability and resilience? how does genetic diversity within component species influence the stability of an ecological community? Species Interaction if species evolve together, do they tend to become more compatible or less so? how does the age structure of component species influence an ecological community? Etc. Species Interaction In all operations, whatever the endpoint, the following are important considerations: (1) speed of attainment; (2) cheapness; (3) reliability in attainment; and (4) stability; In doing restoration: There are a number of ideas and steps: Soil replacement: Direct treatment: Physical treatments: Nutrient addition: Treating toxicities: Adding species: In doing restoration: Soil replacement: simply disregard its individual problems and import a new soil surface, on which a new ecosystem can quickly be established. In a crude sense, this may require little understanding of what is wrong with the site. In doing restoration: Direct treatment: in many situations, however, soil cannot be imported or replaced, and the material existing on a site has to be treated direc tly to achieve restoration. In doing restoration: Physical treatments: efforts are made to loosen subsoil and topsoil by ripping the substrate to depths up to 1 meter. This is then followed by sha llower cultivations, to about 20 cm. Finally, the soil surface is carefully prepared to provide a good seedbed, and a favorable season is chosen for sowing. In doing restoration: Nutrient addition: after all the above problems, there is obviously the need for nutrients. Treating toxicities: Adding species: In doing restoration: Ecological restoration is now being recognized as an important tool that can produce additional improvements in the quality of our resources to support diverse, productive communities of plants and animals that provide significant ecological and social benefits. In doing restoration: Restorationists use the best ecological science available to understand and reverse the sources of damage, restoring the diverse native plant and animal communities, reinstating natural disturbance regimes such as light surface fires, and developing harmonious relationships between people and the land. Why can't we just let nature take its course? More than a century of severe habitat alteration has changed our forests and ecosystems to such an extent that they can no longer heal themselves. Why can't we just let nature take its course? The goals of ecological restoration are to approximate natural ecosystem structure (plant and animal compositions and patterns) and processes (e.g. disturbance regimes such as fire, nutrient cycling, and productivity) that were characteristic of the system before disturbance. Why can't we just let nature take its course? These natural ecosystem structures and processes are critical for maintaining an ecologically sustainable forest and restoring the diversity of wildlife and plants that depend on it