Conservation in Human Modified Landscapes- CH13

13.1 and ●Ecological changes are negative, anthropogenic, large, and accelerating (feedback loops) ●There are few areas on earth that have not been changed/impacted by humans ●Wildlands are primarily sparse forests and barren land, see figure ●Conservation efforts must work with human activities, so protected areas are set out (about 25% of endangered species live outside protected land) ●Evidence of historical disturbance and recovery shows hope for recovery of areas disturbed more recently. ●Extent to which modified lands can support native populations

13.3: Selectively Logged Forests ●In 2005, one third of the world’s forests were designated primarily for timber. ●Severity of logging impacts depend on: o logging intensity o number of trees removed per unit of area o length of rotation time o site management ●Reduced Impact Logging (RIL) - careful planning and controlled harvesting o preliminary inventories o road planning o directional felling ●Practices to improve biodiversity value of logged forests: o designation of no-take areas o maintenance of landscape connectivity ●No evidence for species going extinct due to logging, but evidence that it causes population declines and local extinctions. ●Minimal effects of terrestrial (land-living) species but arboreal (tree-living) vertebrates are especially vulnerable. ex: orangutans and bats. ●Specialist habitat species are most affected.

13.4 Agroforestry Definition: Integration of trees and other woody perennials into crop farming systems. Complex: Trees are co-planted with annual crops, the trees are felled after years, and are replanted. The trees can be maintained or left fallow. Home Gardens: ●Small areas of agricultural land near houses that are cultivated with a mix of annuals and perennials (including trees and shrubs) ●Semi-permanent and more intensively managed than complex agroforests Benefits to Biodiversity Conservation: 1.Through the provision of suitable habitat for forest species in areas that have previously suffered from significant deforestation. 2.The provision of a landscape matrix that permits the movement of species among forest remnants. 3.The provision of livelihoods for local people which can relieve pressure on the remaining areas of forest. Limitations: 1.Ability to maintain a significant amount of regional biota depends on sufficient area of natural habitat to support highly sensitive species and provide source populations. 2.Agroforestry systems can only exist with market incentives and supportive land-use policies.

13.5 Tree plantations ●Potential to make an important contribution to biodiversity conservation for two key reasons: o May more closely reflect the structural complexity of native forest than many more intensive production land-uses. o Occupy a large area of once-forested land in many parts of the world. ●Historically described as “Green Deserts”, however this is misleading. If plantations remain diverse and not monoculture, they may provide valuable habitat for endangered species. ●Conservation value of a given plantation forest is partly determined by how it is managed. o However, the true conservation value of a plantation depends upon the comparison with alternative land-uses that may otherwise exist in its place. Plantations, effectively, can be the “lesser of two evils” when it comes to land use. Erin Kerrigan, Gabe Coleman, Evan Weaselman, Andrew Wilder

13.6: Agricultural land ●With increasing population, the demand for agriculture is also increasing ●Two strategies for how to meet demands of growing population: o Increase agricultural intensity: greater agricultural yields without increasing agricultural land area o Improve quality of overall landscape (matrix): increase connectivity of the landscape, encourage metapopulations

13.7 Urban areas aka “worst case scenario” in ecosystem management ●Developing urban areas irreversibly replace natural habitats ●Urban areas are increasing in the tropics at a high rate ●“it is possible to enhance the conservation value of manmade habitats within human-modified landscapes” ●Urban parks can be more diverse than secondary forest fragments when next to forests ●Organisms such as bees and butterflies are often more diverse in urban parks because of the flowers and plants cultivated by humans. ●Traditional conservation efforts often neglect such “unnatural” environments, therefore crucial to develop more viable strategies for conservation of biodiversity in urban landscapes