Ecological mechanisms linking protected areas to surrounding lands

Ecology Department, Montana State University, Bozeman, Montana 59717-3460, USA.
Ecological Applications (Impact Factor: 4.09). 07/2007; 17(4):974-88. DOI: 10.1890/05-1098
Source: PubMed


Land use is expanding and intensifying in the unprotected lands surrounding many of the world's protected areas. The influence of this land use change on ecological processes is poorly understood. The goal of this paper is to draw on ecological theory to provide a synthetic framework for understanding how land use change around protected areas may alter ecological processes and biodiversity within protected areas and to provide a basis for identifying scientifically based management alternatives. We first present a conceptual model of protected areas embedded within larger ecosystems that often include surrounding human land use. Drawing on case studies in this Invited Feature, we then explore a comprehensive set of ecological mechanisms by which land use on surrounding lands may influence ecological processes and biodiversity within reserves. These mechanisms involve changes in ecosystem size, with implications for minimum dynamic area, species-area effect, and trophic structure; altered flows of materials and disturbances into and out of reserves; effects on crucial habitats for seasonal and migration movements and population source/sink dynamics; and exposure to humans through hunting, poaching, exotics species, and disease. These ecological mechanisms provide a basis for assessing the vulnerability of protected areas to land use. They also suggest criteria for designing regional management to sustain protected areas in the context of surrounding human land use. These design criteria include maximizing the area of functional habitats, identifying and maintaining ecological process zones, maintaining key migration and source habitats, and managing human proximity and edge effects.

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Available from: Ruth S. Defries, Oct 24, 2014
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    • "Whilst the goals of on-farm conservation programmes are diverse, including preservation of genetic diversity of crop varieties (Maxted et al., 2002), a major focus of these programmes is conserving native flora and fauna (Joppa et al., 2008). Factors that make on-farm programmes particularly attractive for conservation include: shrinking conservation budgets, the high management costs of protected areas, rising land acquisition costs (James et al., 1999), the need to minimize disturbances to protected areas from adjacent land uses (Hansen and DeFries, 2007), and the higher cost of managing small conservation areas relative to larger ones (Bruner et al., 2004). Moreover, much biodiversity, and many "
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    ABSTRACT: On-farm conservation programs require land managers to pursue both market and non-market objectives (outcomes). If one can identify objectives that are complementary (co-benefits) and competitive (trade-offs) so that co-benefits can be pursued and trade-offs avoided, one may be able to lower the costs to land managers of on-farm conservation programs. We used data from farms in northern Australia to identify potential trade-offs and co-benefits between market and non-market objectives. We used Data Envelopment Analysis (DEA) to assess the relationship between farm ‘inputs’ (e.g. land, labour, capital) and both market and non-market outcomes (e.g. value of on-farm production, turtle biodiversity). The DEA analysis generated an ‘efficiency score’ for each farm; the best scores were associated with properties that used fewest inputs and had the ‘best’ outcome(s). We then looked for statistically significant relationships between those scores and other variables known to influence outcomes. After controlling for biophysical factors (e.g. rainfall, soil type, presence/absence of water), we found little evidence of trade-offs between market and non-market outcomes. We found that farms with many weeds had poor market efficiency scores, suggesting that weed-reduction programs could generate substantive co-benefits for agriculture and biodiversity. Properties managed by people who preferred a small steady income (over a large uncertain income) had higher non-market efficiency scores, suggesting a link between conservation and attitudes to risk. Our results also suggest that encouraging on-farm agricultural diversification, the adoption of environmentally focused land-management plans, and a generally more positive attitude towards conservation could improve environmental outcomes without compromising market outcomes.
    Biological Conservation 07/2015; In press. DOI:10.1016/j.biocon.2015.07.032 · 3.76 Impact Factor
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    • "Several studies on the effectiveness of human embedded protected areas in conserving biodiversity have recommend to look beyond the protected boundaries to develop management framework coupled with the socio-economic dynamics of the surrounding landscapes (Grumbine, 1994; Hansen and DeFries, 2007; Nagendra et al., 2010a; DeFries et al., 2010). As a result, an integrated approach to landscape management where the protected areas are part of a wide regional landscape has been suggested. "
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    ABSTRACT: High-biodiversity landscapes around the globe are under immense pressure due to the expansion of human activities. To ensure effective monitoring and management of such landscapes, it is necessary to integrate landscape composition and the associated socio-economic processes in the conservation schemes. Artificial Night-Time Light (ANTL) pollution is a recent but striking environmental alteration due to human interventions. It is a major threat for species and communities which co-evolved with invariant natural light patterns over geological times. In spite of its potential key role in re-shaping natural systems, ANTL is seldom considered in macroecology. Remote sensing provides a unique set of tools to integrate ANTL in macroecological studies. In this work, we used remote sensing data of night-time lights along with Enhanced Vegetation Index (EVI) to study the effects and extent of ANTL in the night-time landscape (nightscape) of two protected areas in Italy. Our results showed that a considerable number of semi-natural vegetated patches suffer from ANTL pollution with varying magnitude. We observed a decline in highly suitable patches for biodiversity while the remaining patches were found concentrated in the innermost part of the parks. By simulating an exponential decrease in ANTL we showed that a moderate reduction in ANTL pollution would result in regaining a substantial amount of highly suitable patches for biodiversity. The decline in homogeneous dark patches in vegetated landscapes has negative impacts on biodiversity as well as on the ecosystem services it provides. Therefore, it is high time that the scientific community and the policy-makers increase their efforts to monitor and mitigate the ecological impacts of ANTL on ecosystems. The integration of light pollution in landscape ecology could combine remote sensing with other aspects of light pollution like indirect propagation and spectral composition.
    Ecological Complexity 06/2015; 22:109-120. DOI:10.1016/j.ecocom.2015.02.008 · 1.93 Impact Factor
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    • "In addition, buffer zones and ecological corridors protect the Protected Areas (PAs) from the negative effects of human impact (Brasil, 2004). Despite these laws, little attention has been given to the planning and management of regions surrounding Protected Areas (Andrew and Defries, 2007; Perelló et al., 2012; Wallace et al., 2005). In Brazil, additional guidelines should include the zones surrounding the Protected Areas in biodiversity conservation policies and specific regulations are required to establish the boundaries of buffer zones (Perelló et al., 2012). "
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    ABSTRACT: Changes in the structure of natural habitats surrounding Protected Areas interfere with biodiversity conservation measures. The goals of this research were to analyze the fragmentation and loss of vegetation in three landscape levels surrounding Passo Fundo National Forest, RS, Brazil, in 1986, 1997, and 2011, and to identify the degree of isolation/connectivity of these patches. These analyses were based on landscape metrics, in levels of classes and patches. The area occupied by vegetation increased for three landscape levels, from 1986 to 2011, accompanied by a reduction of the distances between remnants of the forest. Forest coverage was higher in the Protected Area in the other two levels of landscape. This scenario suggests a reduction of agricultural expansion in the region and an attenuation in the process of habitat loss and fragmentation. However, the current proportion (19%) of vegetation outside the Protected Area is still critical for many species.
    Natureza & conservaç~ao revista brasileira de conservaç~ao da natureza 05/2015; 71(1). DOI:10.1016/j.ncon.2015.05.001 · 1.33 Impact Factor
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