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21.
Geospatial data and tools are key in locating lost or missing persons in as short a time as possible. In this study, we used a geographic information system (GIS) to analyze four years of search and rescue (SAR) mission data from Colorado to determine the appropriate use of GIS for volunteer-based SAR organizations with limited resources and GIS expertise. GIS can provide more sophisticated analyses of geospatial data than simple mapping technologies, but our findings indicated that complex spatial analysis might not be required on all missions, because the majority of missions were completed within six to ten hours. Instead, new technologies such as tablets with mapping software and online GIS systems that provide quick and easy access to up-to-date geospatial data such as imagery offer capabilities that could improve mission planning. Here we provide a framework in which SAR missions can apply geospatial technologies to aid with missions, identify critical “hotspots,” and enhance postanalysis and training. The work here is highly applicable for nonprofit SAR groups when deciding on what GIS technologies to consider for their areas. 相似文献
22.
Casey D. SULLIVAN CHEN Pengju Justine Shanti ALEXANDER BAI Defeng SHI Kun 《资源与生态学报(英文版)》2018,9(5):554-565
Human-wildlife conflict (HWC) is a global conservation issue of increasing concern, and understanding the factors driving conflict is crucial for preventing or mitigating it. In many parts of China, large human populations and increasing development has led to an escalation in HWC with both carnivore and prey species. In this paper we assess herder attitudes toward blue sheep (Pseudaois nayaur, Hodgson, 1833), white lipped deer (Carvus albirostris, Przewalski, 1883), red deer (Cervus elaphus, Linnaeus, 1758), and marmot (Marmota himalayana Hodgson, 1841) through interview-based surveys conducted in 46 households across 8 villages in Qilianshan National Nature Reserve, Gansu, China. We also examine the perceived impact of three ecological-restoration policies (anti-grazing, sustainable grazing, and grass-planting policies) on livelihoods, and how this affects attitudes toward wildlife. Herders reported neutral attitudes toward wildlife species in general, but reported negative attitudes towards blue sheep. Mixed-effects modeling revealed that herder attitudes toward the target species varied significantly across villages, but other socioeconomic variables had limited explanatory power for attitudes. Furthermore, we found that while policy implementation was negatively perceived by herders, anti-grazing policy implementation and total policy implementation were positively correlated with positive attitudes toward wildlife, highlighting a potential gap between perceived threats and actual threats. Finally, we show that the leading cause of reported livestock death is preventable disease, alleviation of which may help improve attitudes toward wildlife. 相似文献
23.
ZHANG Chengcheng WANG Jun Justine Shanti ALEXANDER DOU Zhigang WU Liji DONG Wantao Dabuxilite YANG Jucai SHI Kun 《资源与生态学报(英文版)》2018,9(5):566-574
Camera traps serve as an important tool for monitoring species diversity. We used data from camera traps set for capturing snow leopards (Panthera uncia) in the Yanchiwan National Nature Reserve, Gansu Province, China, to assess species richness with respect to mammal and birds species. We also assessed survey efficiency for species detection, and conducted an initial analysis of species interactions. The survey effort of 10, 171 camera workdays yielded 2, 868 suitable animal image events involving 17 mammal and 20 bird species. Among these, the dhole (Cuon alpinus) is considered to be Endangered, the snow leopard and white-lipped deer (Cervus albirostris) Vulnerable, and the Pallas’s cat (Feli smanul), mountain weasel (Mustela altaica), Himalayan griffon (Gyps himalayensis) and cinereous vulture (Aegypius monachus) Near Threatened under the IUCN red list. Fourteen species were also listed as key protected wild animals according to China national standards. Both the rarefaction curves and richness estimators suggested our sampling for mammal and pheasant species is sufficient, while more survey efforts are still needed to detect other bird species. With a focus on the dominant species Eurasian lynx (Lynx lynx), occupancy models were used to estimate site use and detection probability for selected species, and to investigate predator-prey relationships between lynx on the one hand and woolly hare (Lepus oiostolus), pika (Ochotona spp.) and Tibetan partridge (Perdix hodgsoniae) on the other. We give recommendations on how to increase efficiency in camera-based species inventory and biodiversity monitoring. 相似文献
24.
N. C. Hambly S. J. Smartt S. T. Hodgkin R. F. Jameson S. N. Kemp W. R. J. Rolleston I. A. Steele 《Monthly notices of the Royal Astronomical Society》1999,309(4):L33-L36
We present a parallax measurement for the very cool degenerate WD 0346+246, the serendipitous discovery of which was reported by Hambly et al. We find an absolute parallax of 36±5 mas, yielding a distance estimate of 28±4 pc. The resulting absolute visual magnitude of the object is M V =16.8±0.3, making it the second-lowest luminosity white dwarf currently known. We use the distance estimate and measured proper motion to show that the object has kinematics consistent with membership of the Galactic halo. WD 0346+246 is therefore by far the coolest and least luminous of only a handful of plausible halo white dwarf candidates. As such, the object has relevance to the ongoing debate concerning the results of microlensing experiments and the nature of any baryonic dark matter component to the Galactic halo residing in stellar remnants. 相似文献
25.
26.
A Nel BI Pletschke CLW Jones J Kemp G Robinson PJ Britz 《African Journal of Marine Science》2017,39(2):183-192
The effect of kelp Ecklonia maxima inclusion in formulated feeds on abalone growth and gut bacterial communities has not been previously investigated in South Africa. An eight-month on-farm growth trial was conducted with sub-adult Haliotis midae (~43 mm shell length) fed graded levels of kelp in formulated feeds. Kelp inclusion (0.44–3.54% of pellet dry mass) promoted faster growth (65.7–74.5% total mass gain), with better feed and protein conversions (apparent feed conversion ratio [FCR] 1.4–1.8, apparent protein efficiency ratio [PER] 2.3–2.7), as compared with the non-supplemented feed (52.3% total mass gain, FCR 2.1, PER 1.9; p < 0.001). Abalone-gut bacterial DNA was sequenced using 16S rRNA gene pyrosequencing and the sequences were clustered into operational taxonomic units (OTUs) at a 97% similarity level. A supplementary 16S rRNA gene denaturing gradient gel electrophoresis (DGGE) analysis was employed. The dominant OTUs differed in terms of their relative abundances, with an autochthonous Mycoplasma strain being significantly more abundant (p = 0.03) in the gut of abalone fed a kelp-supplemented feed. The DGGE band patterns displayed higher within-group variability for abalone fed the control diet, suggesting that dietary kelp inclusion promotes gut-bacteria homeostasis. This may contribute to better feed utilisation and growth in abalone fed kelp-supplemented feeds. 相似文献
27.
28.
This study describes the influence of submersed plant beds on spatial distributions of key water quality variables. An on-board
flow-through water sampling system was used to investigate patterns in turbidity, chlorophyll-a, temperature, dissolved oxygen, and pH across a robust stand of the submersed plant Stuckenia pectinata. Spatially interpolated maps show that water quality conditions were significantly altered within this plant bed, especially
during months of peak biomass, and that reduction of suspended particles focused at the bed’s edge. Comparison with a suite
of submersed plant beds indicated that patterns were related to canopy height, shoot density, and cross-shore bed width. Wide
and dense stands with tall canopies showed reduced turbidity and increased light penetration, while smaller sparser beds often
showed elevated within-bed turbidity. These results suggest that bed effects on water quality conditions vary seasonally with
plant canopy architecture and bed size, providing tentative guidelines for restoring self-sustaining beds. 相似文献
29.
To assess the potential impact of climate changes on pasture production in the North Island, New Zealand, eight climate scenarios
of increased temperature and increased (or decreased) rainfall were investigated by integrating a polynomial regression model
for pasture production with a Geographic Information System (GIS). The results indicated that the climate change scenarios
assuming an increase in temperature by 1–2°C and a rainfall change by −20 to +20% would have a very significant impact on
pasture production with a predicted pasture production variation from −46.2 to +51.9% compared with the normal climate from
1961–1990. Increased temperature would generally have a positive effect on pasture production in the south and southeast of
the North Island, and increased rainfall would have a positive effect in the central, south and southeast of the North Island
and a negative effect in the north of the North Island. The interaction of decreased rainfall and increased temperature would
have a negative impact for the whole North Island except some central areas with high rainfall. Relevant management practices
for coping with potential climate change are discussed. 相似文献
30.
W. M. Kemp W. R. Boynton J. J. Cunningham J. C. Stevenson T. W. Jones J. C. Means 《Marine environmental research》1985,16(4):255-280
Phytotoxicities of the herbicides, atrazine and linuron, were evaluated for two species of submersed vascular plants (Potamogeton perfoliatus, L. Myriophyllum spicatum, L.) which, until the late 1960s, had been abundant in Chesapeake Bay. Plants were grown in 50-liter laboratory microcosms, containing filtered estuarine water and sediments for a period of 5 weeks and then treated with atrazine or linuron at initial concentrations of 0, 5, 50, 100, 500 and 1000 gmg/liter. Plant responses were measured primarily in terms of apparent O2 production, P3, and above-ground biomass for 4 weeks post treatment. In general, at ≥ 50 gmg/liter there was a significant depression in Pa for both species and herbicides. However, M. spicatum appeared to be less sensitive, with a significant enhancement in Pa of this species at 5 gmg/liter, and linuron was slightly more effective than atrazine at reducing Pa for both species. Treatment effects on biomass generally paralleled those for Pa. In spite of relatively constant atrazine concentrations (84–89 % remaining at termination), both species exhibited evidence of photosynthetic recovery 2–3 weeks after treatment at concentrations ≤ 100 gmg/liter. Using an exponential dose-response model, I50 (concentration for 50 % photosynthetic inhibition), ranged from 45–117 gmg/liter for all experiments. In general, in situ concentrations of atrazine and linuron in Chesapeake Bay and its tributaries appear to be sufficient to result in small reductions in Pa (2–10%, estimated from dose-response model) during a typical growing season. While such effects may be important for the survival of otherwise stressed plant populations, they suggest that these herbicides, per se, were not the cause of the general decline in abundance of these plants. 相似文献