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891.
Maryland's Green Infrastructure—Using Landscape Assessment Tools to Identify a Regional Conservation Strategy 总被引:1,自引:0,他引:1
Maryland is growing at a very rapid pace. Compounding the problems associated with rapid growth is the scattered pattern of development that consumes an excessive amount of land and fragments the landscape. As land use changes, wildlife habitat and migration corridors are lost and normal ecosystem functions are disturbed or destroyed. While land use planners and developers are attempting to minimize such impacts, they do not always know where key natural lands and corridors are situated. The Green Infrastructure Assessment (GIA) provides this information and can be used to identify a greenway network that will protect the most critical lands in the state before they are gone foreover. Using GIS and principles of landscape ecology, the Maryland Department of Natural Resources is identifying an interconnected network of "hubs" and "corridors" that are now the focus of state and local agency deliberations and revisions. Elements of the network are being prioritized for conservation and restoration activities based on ecological parameters (e.g., sensitive species, important wetlands or riparian zones, etc.) and threat parameters (e.g., protection status, development pressure, etc.). The goal of GIA is to help identify an ecologically sound open space network, and ultimately, to incorporate the agreed upon network into state and local land conservation planning. 相似文献
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G. H. R. von Koenigswald 《Die Naturwissenschaften》1953,40(4):128-137
898.
In Australia, local communities often enact Community-Based Initiatives (CBIs) to respond to climate change through Climate Change Adaptation (CCA). CBIs can also be integrated into the Disaster Risk Reduction (DRR) agenda. The paper explores the extent to which CBIs promote the mainstreaming of CCA into DRR. Primary data were obtained from interviews with representatives of CBIs and supporting organisations in three local governments of the Hunter Valley (New South Wales, Australia). Findings show that CBIs recognise the potential contribution of climate change in modifying the local hazard profile. CBIs mainstream CCA into DRR by following four approaches: environmental and social justice; sustainability and transition; ecosystem-based approach; and adaptive planning. Partnerships were identified both among CBIs and between CBIs and City Councils; however, conflicts between CBIs, City Councils and business actors emerged, and a lack of commitment by multi-level governments in responding to climate change was revealed. The findings show that CBIs consider CCA and DRR within a broad everyday context related to vulnerability and local development. But we argue that assigning responsibility for climate change issues to CBIs is not a panacea and should not be the only local climate change response. Instead, CBIs need to be included in a larger and long-term commitment by actors that possess access to resources, such as higher levels of government. The paper provides a local Australian perspective on the effectiveness of mainstreaming CCA into DRR and furthers the conversation for the benefit of other communities facing similar challenges. 相似文献
899.
The behavioral response of the obligate bamboo-nesting ant Cataulacus muticus to nest flooding was studied in a perhumid tropical rainforest in Malaysia and in the laboratory. The hollow internodes of
giant bamboo, in which C. muticus exclusively nests, are prone to flooding by heavy rains. The ants showed a two-graded response to flooding. During heavy
rain workers block the nest entrances with their heads to reduce water influx. However, rainwater may still intrude into the
nest chamber. The ants respond by drinking the water, leaving the nest and excreting water droplets on the outer stem surface.
This cooperative 'peeing' behavior is a new survival mechanism adaptive to the ants' nesting ecology. Laboratory experiments
conducted with two other Cataulacus species, C. catuvolcus colonizing small dead twigs and C. horridus inhabiting rotten wood, did not reveal any form of water-bailing behavior.
Received: 3 August 2000 / Accepted in revised form: 6 November 2000 相似文献
900.
Ernest M. Weber Ahmad A. Hassan 《Journal of the American Water Resources Association》1972,8(1):198-206
To answer the difficult question of how to integrate operation of ground and surface water supplies into their management plans, the decision-makers must be able to predict the effects of various alternative modes of operation and meteorological conditions on the groundwater basin. Many types of models have been used for simulating the behavior of groundwater basins under these changes. Analog simulators, analog computers, and digital computers have been employed for model development. To achieve plausible models, detailed hydraulic and hydrologic characteristics are required, such as data on transmissivity, storage, and net deep percolation. These data are used in the equations that form the model. Water quality, which cannot be separated from quantity, deserves equal consideration. Recently, considerable efforts have been made to develop water quality prediction tools through the use of modeling techniques. 相似文献