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61.
Using a map overlay procedure in a Geographical Information System environment, we quantify and map major land use and land cover (LULC) change patterns in Uganda period 1990–2005 and determine whether the transitions were random or systematic. The analysis reveals that the most dominant systematic land use change processes were deforestation (woodland to subsistence farmland—3.32%); forest degradation (woodland to bushland (4.01%) and grassland (4.08%) and bush/grassland conversion to cropland (5.5%) all resulting in a net reduction in forests (6.1%). Applying an inductive approach based on logistic regression and trend analyses of observed changes we analyzed key drivers of LULC change. Significant predictors of forest land use change included protection status, market access, poverty, slope, soil quality and presence/absence of a stream network. Market access, poverty and population all decreased the log odds of retaining forests. In addition, poverty also increased the likelihood of degradation. An increase in slope decreased the likelihood of deforestation. Using the stock change and gain/loss approaches we estimated the change in forest carbon stocks and emissions from deforestation and forest degradation. Results indicate a negligible increase in forest carbon stocks (3,260 t C yr-1) in the period 1990–2005 when compared to the emissions due to deforestation and forest degradation (2.67 million t C yr-1). In light of the dominant forest land use change patterns, the drivers and change in carbon stocks, we discuss options which could be pursued to implement a future national REDD plus strategy which considers livelihood, biodiversity and climate change mitigation objectives.  相似文献   
62.
ABSTRACT: Statutory and case law at the state level provide critical legal frameworks for water management. As many state governments struggle to improve efficiency in water management and resolve conflicts over water usage, they must continually assess the efficacy of their state water law. Most states have water laws that are disconnected and overlapping. This article presents a methodology to assess state water law and take first steps toward a comprehensive state water resources act. The methodology is driven by issues and conflicts in water management. It synthesizes management and legal analyses into a process that incorporates the diverse perspectives of state water stakeholders. The results of the analysis are identification of management issues, profiles of state water law, and explorations of legal options that are available to the state government. Illinois is provided as a case study for this methodology.  相似文献   
63.
Species' conservation relies on understanding their seasonal habitats and migration routes. North Atlantic right whales (Eubalaena glacialis), listed as endangered under the U.S. Endangered Species Act, migrate from the southeastern U.S. coast to Cape Cod Bay, Massachusetts, a federally designated critical habitat, from February through May to feed. The whales then continue north across the Gulf of Maine to northern waters (e.g., Bay of Fundy). To enter Cape Cod Bay, right whales must traverse an area of dense shipping and fishing activity in Massachusetts Bay, where there are no mandatory regulations for the protection of right whales or management of their habitat. We used passive acoustic recordings of right whales collected in Massachusetts Bay from May 2007 through October 2010 to determine the annual spatial and temporal distribution of the whales and their calling activity. We detected right whales in the bay throughout the year, in contrast to results from visual surveys. Right whales were detected on at least 24% of days in each month, with the exception of June 2007, in which there were no detections. Averaged over all years, right whale calls were most abundant from February through May. During this period, calls were most frequent between 17:00 and 20:00 local time; no diel pattern was apparent in other months. The spatial distribution of the approximate locations of calling whales suggests they may use Massachusetts Bay as a conduit to Cape Cod Bay in the spring and as they move between the Gulf of Maine and waters to the south in September through December. Although it is unclear how dependent right whales are on the bay, the discovery of their widespread presence in Massachusetts Bay throughout the year suggests this region may need to be managed to reduce the probability of collisions with ships and entanglement in fishing gear.  相似文献   
64.
This paper presents a Business Recovery Assessment Framework (BRAF) to help researchers and practitioners design robust, repeatable, and comparable studies of business recovery in various post‐disruption contexts. Studies assessing business recovery without adequately considering the research aims, recovery definitions, and indicators can produce misleading findings. The BRAF is composed of a series of steps that guide the decisions that researchers need to make to ensure: (i) that recovery is indeed being measured; (ii) that the indicators of recovery that are selected align with the objectives of the study and the definition of recovery; and, where necessary, (iii) that appropriate comparative control variables are in place. The paper draws on a large dataset of business surveys collected following the earthquakes in Canterbury, New Zealand, on 4 September 2010 and 22 February 2011 to demonstrate the varied conclusions that different recovery indicators can produce and to justify the need for a systematic approach to business recovery assessments.  相似文献   
65.
We tracked the long-term movements of 70 parrotfishes, surgeonfishes and goatfishes captured inside a small (1.3 km2) marine protected area (MPA: Kealakekua Bay Marine Life Conservation District, Hawaii) by implanting them with small transmitters and deploying underwater monitoring devices inside the bay and along 100 km of the adjacent west Hawaii coastline. Individual fish were detected inside Kealakekua Bay for up to 612 days but many were detected for much shorter periods (median = 52 days). There were species-specific differences in the scale of movements and habitats used, but most fish utilized between 0.2 and 1.6 km of coastline, and individuals of each species showed some degree of diel habitat shift. A wide variety of reef fishes captured inside the MPA swam back and forth across an MPA boundary intersecting continuous reef (i.e., this boundary was porous to reef fish movements), but only 1 of 11 species tagged crossed a wide sandy channel inside Kealakekua Bay suggesting that this feature may function as a natural barrier to movements. Results indicate relatively small MPAs (<2 km of coastline) could provide effective, long-term protection for multi-species assemblages of reef fishes provided that boundaries are situated along major habitat breaks (e.g., large sand channels between reefs) that may serve as natural barriers to reef fish movements. It is crucial that a multi-species approach be used when assessing MPA effectiveness.  相似文献   
66.
Adaptive governance is advanced as a potent means of addressing institutional fit of natural resource systems with prevailing modes of political–administrative management. Its advocates also argue that it enhances participatory and learning opportunities for stakeholders over time. Yet an increasing number of studies demonstrate real difficulties in implementing adaptive governance ‘solutions’. This paper builds on these debates by examining the introduction of adaptive governance to water management in Chiang Mai province, north-west Thailand. The paper considers, first, the limitations of current water governance modes at the provincial scale, and the rationale for implementation of an adaptive approach. The new approach is then critically examined, with its initial performance and likely future success evaluated by (i) analysis of water stakeholders’ opinions of its first year of operation; and (ii) comparison of its governance attributes against recent empirical accounts of implementation difficulty and failure of adaptive governance of natural resource management more generally. The analysis confirms the potentially significant role that the new approach can play in brokering and resolving the underlying differences in stakeholder representation and knowledge construction at the heart of the prevailing water governance modes in north-west Thailand.  相似文献   
67.
The purpose of this paper is to conceptualize the hitherto separate domains of Cyberspace and International Relations into an integrated socio-technical system that we jointly call the cyber International Relations (Cyber-IR) system and to identify and analyze its emergent properties utilizing the methods common to science and engineering systems adapted here for the social sciences. Our work is an exploration in both theory and methodology. This paper (a) identifies the actors and functions in the core systems, Cyberspace, and IR, (b) disambiguates system boundary, (c) creates a design structure matrix (DSM), a matrix of the interdependencies among functions of actors, (d) analyzes DSM qualitatively to show multiple interdependent and heterogeneous Cyber-IR properties, and (e) analyzes quantitatively the differential importance of core functions as well as the impact of actor attributes on influence in Cyber-IR. This work forms a baseline for further understanding of the nature of the heterogeneous influences of the various actors and the various outcomes that could result from it.  相似文献   
68.
Canadian and US marine conservation law, and other related law, was analyzed to determine if it reflected ecological criteria needed to implement connectivity among marine protected areas of the northeast Pacific in the proposed trilateral Baja to Bering Sea (B2B) initiative. The analysis included both nations’ federal laws and those of California, Oregon, Washington, Alaska, and British Columbia. While legal provisions exist already to implement marine protected areas for varying reasons, there is little capacity in most laws to create connectivity among them for conservation purposes. Only California's legislation contained explicit provisions for all the criteria. Other federal, state, and provincial laws, while containing provisions for species at risk and vulnerable habitats, generally lacked explicit provisions for the vital criteria, size of area, migratory patterns, and recruitment patterns. Implementation, future management, and protection of the proposed B2B marine network would be facilitated by amendment of both Canadian and US laws. Some of the ecological criteria are already implied implicitly or vaguely, but they need to be made explicit in the amended law. The legislative model of California could serve as a template for amending the laws of other jurisdictions in the B2B venture.  相似文献   
69.
The environmental sciences/studies movement, with more than 1000 programs at colleges and universities in the United States and Canada, is unified by a common interest??ameliorating environmental problems through empirical enquiry and analytic judgment. Unfortunately, environmental programs have struggled in their efforts to integrate knowledge across disciplines and educate students to become sound problem solvers and leaders. We examine the environmental program movement as a policy problem, looking at overall goals, mapping trends in relation to those goals, identifying the underlying factors contributing to trends, and projecting the future. We argue that despite its shared common interest, the environmental program movement is disparate and fragmented by goal ambiguity, positivistic disciplinary approaches, and poorly rationalized curricula, pedagogies, and educational philosophies. We discuss these challenges and the nature of the changes that are needed in order to overcome them. In a subsequent article (Part 2) we propose specific strategies for improvement.  相似文献   
70.
Animal color patterns often reflect a compromise between natural selection for crypsis or inconspicuousness to predators and sexual selection for conspicuousness to potential mates. In leaf litter-dwelling wolf spider species like Schizocosa ocreata, body coloration often closely matches the background coloration of a generally brown environment. However, body parts used in communication should exhibit high contrast against background coloration. We used spectral analysis to examine male and female S. ocreata for matching and contrasting coloration against leaf litter. Values were plotted in multivariate color space, based on reflectivity in different frequency ranges. When viewed from above, colors of both males and females overlap with values for dead brown leaf litter and soil, suggesting cryptic coloration when viewed by potential predators. However, when viewed from a lateral perspective, both males and females show color values that are polar opposites of litter backgrounds, suggesting higher contrast when viewed by other spiders. Moreover, male secondary characters used in visual signaling by S. ocreata (tibia brushes) show the highest level of background contrast. These findings suggest that S. ocreata wolf spiders have color patterns that provide both crypsis and background contrast at the same time, depending on receiver viewing perspective.  相似文献   
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