Neil Pelkey

Juniata College · Department of Environmental Sciences

Recent studies have documented changes in vegetation cover due to invasive herbivores in the Andaman Islands. In this study we demonstrate that the change is large enough and rapid enough to be detected by remotely sensed data. Using the freely available Nor-malised Difference Vegetation Index (NDVI) imagery, we examined changes in vegetation cover...

Watershed development (WSD) is an important and expensive rural development initiative in India. Proponents of the approach contend that treating watersheds will increase agricultural and overall biomass productivity, which in turn will reduce rural poverty. We used satellite-measured normalized differenced vegetation index as a proxy for land prod...

We analyse the suitability of Government of India’s 2003 and 2008 common guidelines for prioritising micro-watersheds for restoration. These guidelines attempt to balance the need for improved hydraulic function with poverty alleviation and agricultural productivity. To do so, they provide a set of sub-criteria for prioritising micro-watersheds for...

Das and Vincent (1) conclude that mangroves reduced the death toll from storm surge in the Orissa Super Cyclone. However, it is unclear from their analyses whether or not this effect occurs independently over and above that of other variables known to affect inundation by long-period waves, such as distance from the coast and topography (2). Furthe...

Richness is shown by rarefaction curves which describe how the number of species changes with the number of individuals sampled, thus controlling for both sampling effort and bird density. Thick lines indicate means of rarefaction curves calculated for each transect and thin lines indicate 95% confidence intervals. (0.12 MB TIF)

Two numbers are listed for each species in each habitat. The first is the proportion of points in that habitat in which the species was detected. The second is the number of birds of each species detected within 50 m per point for each habitat class divided by the number of counts and the area of the 50 m radius circle. Note that these indices are...

Means and SE are presented. Habitat classes with the same letter are not significantly different from one another in a Tukey HSD multiple means comparison. (E = early pine plantation, M = mid-aged pine plantation, L = late pine plantation, N = native forest, X = Exurban areas, T = thinned native forest.) (0.10 MB TIF)

Evenness is shown by the probability of interspecific encounter (PIE). Thick lines indicate means of rarefaction curves calculated for each transect and thin lines indicate 95% confidence intervals. PIE controls for both sampling effort and bird density, and uses repeated re-sampling of the data to calculate the probability that the next bird sampl...

Each point represents the position in ordination space of the bird community detected at one point count. The two axes show the relative position of each point count in the multi-dimensional space defined by the species found at each point count. Thus point counts with similar bird communities cluster together on the graph. The first axis (DCA 1) i...

Results are presented for birds detected within 50m of the count center and for all birds detected regardless of distance from count center. Note that these indices are affected by differential detectability in each habitat and true density will therefore differ from these indices (see Caveats section of the Discussion for further details on detect...

Native forests are shrinking worldwide, causing a loss of biological diversity. Our ability to prioritize forest conservation actions is hampered by a lack of information about the relative impacts of different types of forest loss on biodiversity. In particular, we lack rigorous comparisons of the effects of clearing forests for tree plantations a...

In this chapter we examine three frameworks that have been used to explain the success of a variety of policymaking institutions: Institutional Rational Choice, Social Capital, and the Advocacy Coalition Framework.

Over the past two decades, forests in the southeastern United States have undergone dramatic changes as the result of urban sprawl and conversion to intensively managed pine plantations. The Cumberland Plateau, an important ecoregion in the southeastern United States, contains some of the largest remaining tracts of privately owned, native hardwood...

Studies assessing temporal changes in vegetation using satellite imagery are complicated by: (1) high interseasonal and interannual variation in phenology that make vegetation comparisons difficult; (2) anthropogenic pressures on the habitats that vary by geographic region and habitat type; and (3) spatial resolution and processing characteristics...

Public policymaking and implementation in the United States are increasingly handled through local, consensus-seeking partnerships involving most affected stakeholders. This paper formalizes the concept of a stakeholder partnership, and proposes techniques for using interviews, surveys, and documents to measure each of six evaluation criteria. Then...

Two main goals are achieved in this review of the empirical literature on factors affecting conflict resolution in watershed partnerships. The first is an assessment of two public policy theories relevant to partnership structure and function. The second is a set of practical suggestions for designing successful partnerships. The 37 available studi...

Using normalized difference vegetation index (NDVI) imagery, we examined changes in vegetative cover across Tanzania and found that overall greenness increased over 13 years from 1982 to 1994. We then assigned 8 km pixels to different habitat types using a vegetation map compiled from Landsat satellite imagery between 1978 and 1982. We found that w...

Watershed management in the United States is increasingly handled through decentralized, consensus-seeking partnerships involving multiple levels of government plus most affected stakeholders. Systematic measures of partnership success are necessary to keep local decisionmakers accountable, and to enable research on factors that influence partnersh...

Populations of leopards and tigers in the Kalakad-Mundanthurai Tiger Reserve, India, appear to be declining. To identify the cause of this decline, we examined the diets and the relative densities of leopards and tigers, comparing scat from this park with that from the Mudumalai Wildlife Sanctuary, a park known to have high leopard and tiger densit...

We examined the effects of protection from human activities and effects of tourist hunting on densities of 21 large mammal species in Tanzania. Aerial censuses revealed that mammal biomass per km2 was highest in National Parks. Densities of nine ungulate species were significantly higher in National Parks and Game Reserves than in areas that permit...

In Tanzania, where tourist hunting is employed as a conservation tool for habitat protection, information on population sizes and hunting offtake was used to assess the impact of tourist hunting on mammal densities. In general, tourist hunting pressure was unrelated to local population sizes, but for most species, animals were removed at a level of...

"The Cauvery River and its tributaries form definitely the most contentious , if not the most important, watershed in southern India. About half of the watershed exists in Karnataka, the rest is in Tamil Nadu. The Cauvery, like her multi-state and multinational cousins --the Mekong (Southeast Asia), the Colorado (Western U.S.), and the Okavango (so...

Models of policymaking by regulatory agencies need (1) to avoid focusing on a single causal factor, and (2) include analyses of the costs and efficacy of a variety of instruments—law, budgetary review, appointments, direct participation, evaluative studies—by which external actors can influence agency policy. The article proposes a conceptual frame...

"Hall and Bawa (1993) warn that using Non-Timber Forest Products (NTFP's) as an alternative source of income in eco-development schemes may lead to the same over-harvesting problems that tradition timber products have suffered in the last century in the tropics. They suggest that careful monitoring and management may be necessary to avoid biologica...