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121.
Lisa Groshong Sonja Wilhelm Stanis Mark Morgan Christine Jie Li 《Environmental management》2020,65(1):98-110
This study examined the role of place attachment in determining visitors’ willingness to engage in climate friendly behavior in parks and support for management actions to minimize climate-change impacts. The sample consisted of visitors to Missouri State Parks (n = 1775). Place attachment was measured using 12 items of place identity, place dependence, and social bonding. Exploratory factor analysis of climate friendly behavior items revealed two dimensions: Visit based (i.e., short-term, immediate actions individuals could take during their visit) and Big Picture (i.e., advocacy actions that suggest a long-term engagement with parks). A path analysis demonstrated that the dimensions of place attachment predict climate friendly behavior and support for climate friendly management action in different ways. Specifically, place identity increased climate friendly behavior (big picture) and place dependence increased both climate friendly behavior (visit based) and support for climate friendly management action. Findings from this study provided evidence for the importance of place attachment as a means for engaging visitors in climate-related actions both in and beyond the park setting. 相似文献
122.
Matthew J. Ashton Raymond P. Morgan II Scott Stranko 《Environmental monitoring and assessment》2014,186(2):1167-1182
In an ongoing effort to propose biologically protective nutrient criteria, we examined how total nitrogen (TN) and its forms were associated with macroinvertebrate communities in wadeable streams of Maryland. Taxonomic and functional metrics of an index of biological integrity (IBI) were significantly associated with multiple nutrient measures; however, the highest correlations with nutrients were for ammonia-N and nitrite-N and among macroinvertebrate measures were for Beck’s Biotic Index and its metrics. Since IBI metrics showed comparatively less association, we evaluated how macroinvertebrate taxa related to proposed nutrient criteria previously derived for those same streams instead of developing nutrient–biology thresholds. We identified one tolerant and three intolerant taxa whose occurrence appeared related to a TN benchmark. Individually, these taxa poorly indicated whether streams exceeded the benchmark, but combining taxa notably improved classification rates. We then extracted major physiochemical gradients using principal components analysis to develop models that assessed their influence on nutrient indicator taxa. The response of intolerant taxa was predominantly influenced by a nutrient-forest cover gradient. In contrast, habitat quality had a greater effect on tolerant taxa. When taxa were aggregated into a nutrient sensitive index, the response was primarily influenced by the nutrient-forest gradient. Multiple lines of evidence highlight the effects of excessive nutrients in streams on macroinvertebrate communities and taxa in Maryland, whose loss may not be reflected in metrics that form the basis of biological criteria. Refinement of indicator taxa and a nutrient-sensitive index is warranted before thresholds in aquatic life to water quality are quantified. 相似文献
123.
Most agricultural information is reported by government sources on a state or county basis. The purpose of this study was
to demonstrate use of geospatial data, the 2002 Agricultural Cropland Data Layer (CDL) for the mid-Atlantic region, to characterize
agricultural, environmental, and other scientific parameters for the Chincoteague Bay subbasin using geographic information
systems. This study demonstrated that agriculture can be characterized accurately on subbasin and subwatershed bases, thus
complimenting various assessment technologies. Approximately 28% of the dry land of the subbasin was cropland. Field corn
was the largest crop. Soybeans, either singly or double-cropped with wheat, were the second most predominant crop. Although
the subbasin is relatively small, cropping practices in the northern part were different from those in the southern portion.
Other crops, such as fresh vegetables and vegetables grown for processing, were less than 10% of the total cropland. A conservative
approximation of the total pesticide usage in the subbasin in 2002 was over 277,000 lbs of active ingredients. Herbicides
represented the most frequently used pesticides in the subbasin, both in number (17) and in total active ingredients (over
261,000 lbs). Ten insecticides predominated in the watershed, while only small quantities of three fungicides were used. Total
pesticide usage and intensity were estimated using the CDL. Nutrient inputs to cropland from animal manure, chemical fertilizer,
and atmospheric deposition were modeled at over 30 million pounds of nitrogen and over 7 million pounds of phosphorous. Crops
under conservation tillage had the largest input of both nutrients. 相似文献
124.
Regional Environmental Change - Land degradation in many Pacific Island Countries (PICs) has become an emerging concern in recent years. The causes of land degradation in PICs include:... 相似文献
125.
Jennifer R. Ovenden Jess A. T. Morgan Raewyn Street Andrew Tobin Colin Simpfendorfer William Macbeth David Welch 《Marine Biology》2011,158(7):1497-1509
Biodiversity of sharks in the tropical Indo-Pacific is high, but species-specific information to assist sustainable resource
exploitation is scarce. The null hypothesis of population genetic homogeneity was tested for scalloped hammerhead shark (Sphyrna lewini, n = 237) and the milk shark (Rhizoprionodon acutus, n = 207) from northern and eastern Australia, using nuclear (S. lewini, eight microsatellite loci; R. acutus, six loci) and mitochondrial gene markers (873 base pairs of NADH dehydrogenase subunit 4). We were unable to reject genetic
homogeneity for S. lewini, which was as expected based on previous studies of this species. Less expected were similar results for R. acutus, which is more benthic and less vagile than S. lewini. These features are probably driving the genetic break found between Australian and central Indonesian R. acutus (F-statistics; mtDNA, 0.751–0.903, respectively; microsatellite loci, 0.038–0.047 respectively). Our results support the spatially
homogeneous monitoring and management plan for shark species in Queensland, Australia. 相似文献
126.
Lauren J. OliverByron J.T. Morgan Sarah M. DurantNathalie Pettorelli 《Ecological modelling》2011,222(3):776-784
Accurate estimates of demographic parameters are key for understanding and predicting population dynamics and for providing insights for effective wildlife management. Up until recently, no suitable methodology has been available to estimate survival probabilities of species with asynchronous reproduction and a high level of individual variation in capture probabilities. The present work develops a capture-mark-recapture model for cheetahs in the Serengeti National Park, Tanzania, which (a) deals with continuous reproduction, (b) takes into account the high level of individual heterogeneity in capture probabilities and (c) is spatially explicit. Results show that (1) our approach, which is an extensive modification of the Cormack-Jolly-Seber model, provides a lower female adult survival estimate and a higher male adolescent survival estimate than previous approaches to estimate cheetah survival in the area, (2) using sighting location alone is not sufficient to capture the individual variation in resighting probabilities for both sexes, and (3) precision in estimated survival probabilities is generally increased. Species which are individually recognizable, wide-ranging and/or where individuals differ substantially in sightability are particularly appropriate to our modelling approach, and our methodology would thus be appropriate for a wide number of species to provide more accurate estimates of survival. 相似文献
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130.
Gnathiid isopods were collected from Heron and Lizard Islands, Great Barrier Reef, Australia. The presence of three species
was inferred using ribosomal DNA internal transcribed spacer 2 (ITS2) sequences from both adult and juvenile stages. Having
matched DNA sequences from all stages of one of the species' life cycles, we can now identify those individuals based purely
on their morphology. The level of variation between species ranged from 38.5 to 43% compared to within-species variation levels
of <1%.
Received: 30 June 1999 / Accepted: 3 December 1999 相似文献