17,522 research outputs found
Desktop Method to Map and Assess Environmental Impacts of Formal and Informal Mountain Biking Trails in an Urban National Park
No full textRecreational trails, including informal trails created by visitors, have a range of ecological impacts, but mapping and assessing these impacts can be expensive and time-consuming. It is increasingly possible to harness publicly available data posted by park visitors to fitness platforms and combine it with other spatial and field data to help prioritise management actions and enhance conservation and visitor experiences. Here we outline and then apply such a desktop methodology to assess the extensive network of formal and informal mountain biking trails in a popular urban national park in Australia. Across Nerang National Park on the Gold Coast, 31.4 km of formal and 36.2 km of informal mountain bike trails were identified and assessed using data from the popular fitness platform Trailforks and existing trail records from managers. Informal mountain biking trails were mostly in the higher and more remote parts of the Park on steeper slopes and were generally less popular than the formal trails closer to the main entrance. The informal trails have resulted in the loss of 0.8% of vegetation, increased fragmentation and potentially disturb wildlife across 13% of the Park, with some informal trails traversing an important wetland catchment. The results demonstrate the scale and nature of potential impacts of informal trails, which have doubled the area of trails in Nerang National Park. They highlight the need for specific management actions, such as closing and restoring informal trails, particularly when poorly designed and in areas of high conservation value.Full Tex
Why are some animals popular with wildlife tourists: insights from South Africa
No full textWildlife tourism is an important type of ecotourism including in South Africa. We considered how the aesthetic value theory can be applied to wildlife tourism by assessing the relative popularity of species with tourists in South Africa and which traits predicted popularity. When data from six published visitor surveys across seven protected areas were combined, we found that only 26 species out of 299 mammals and 850 + birds were selected by 2245 tourists. Elephant (48%), black and white rhinos (36%), lion (36%), cheetah (35%) and giraffe (34%) were the most popular in these visitor surveys with similar results reported in data from destination marketing and social media, but not wildlife auctions. When 13 species traits were assessed using ordinations and Generalised Linear Models, traits associated with specific aesthetics were important as large mammals that use open vegetation, with highly contrasting coat colours and/or are fluffy were most popular. Given the diversity of animals in South Africa, those responsible for wildlife tourism opportunities could diversify the types of species used in marketing to better match animals likely to be encountered in the wild, enhancing repeat visitor experiences while promoting the conservation of more species in the region.No Full Tex
Pickering Emülsiyonlarının Üretimi İçin Karıştırmalı Tank Tasarımı
No full textBu proje kapsamında gerçekleştirilen çalışmanın amacı Pickering emülsiyonlarının üretimi için
en uygun tank ve karıştırıcı geometrisinin belirlenmesi ve hidrodinamiğin emülsiyon kararlılığı
üzerine etkilerinin incelenmesidir. Hidrofilik özellikte küresel cam tozu kullanılarak su
içerisinde yağ Pickering emülsiyonu üretilmiştir. Silikon yağı dağılan faz olarak, saf su ise ana
faz olarak seçilmiştir. Pickering emülsiyonlarının üretimi engelli ve engelsiz tanklarda
yapılmıştır. Engelli tanklarda şaft her zaman merkezde, engelsiz tanklarda ise şaft üç ayrı
konumda olacak şekilde karıştırma yapılmıştır. İki ayrı karıştırıcı tipi kullanılmıştır: Rushton
türbini (RT) ve aşağı yönlü akış sağlayan eğimli bıçaklı karıştırıcı ucu (PBTD-pitched blade
turbine). Bu iki karıştırıcı türü iki farklı boyutta kullanılmıştır: T/2 ve T/3 (T tank iç çapını ifade
etmektedir). Sabit enerji dağılımı (P/?V), Reynolds sayısı, karıştırıcı ucu hızı (?ND) ve Weber
sayısı gibi hidrodinamik parametreler değiştirilerek farklı hidrodinamik koşullar
oluşturulmuştur. Bu farklı hidrodinamik koşulların Pickering emülsiyonu üretimi üzerindeki
etkileri damlacık çapı analizi ile belirlenmiştir. Analiz için Malvern Mastersizer 3000 cihazı
kullanılmıştır. Bu analiz sonuçlarına göre, engelli tanklarda üretilen Pickering emülsiyonu için
RT T/2 karıştırıcı ucunun en küçük damlacıkları ürettiği gözlemlenmiştir. Engelsiz tanklarda
üretilen Pickering emülsiyonu için ise RT T/3 karıştırıcı ucu tipi ile şaftın merkezden 2 cm
uzakta olduğu durumda en iyi sonuç elde edilmiştir.The aim of this project was to determine the optimum tank and impeller geometry for the
production of Pickering emulsions and to investigate the effect of hydrodynamics on emulsion
stability. Oil-in-water type Pickering emulsion was produced using hydrophilic solid glass
beads. Silicone oil was chosen as the dispersed phase and distilled water was chosen as the
continuous phase. Production of Pickering emulsions was done in baffled and unbaffled tanks.
In baffled tanks the shaft was positioned at the center of the tank, but in unbaffled tanks shaft
was positioned at three different positions. Two different types of impeller were used: Rushton
turbine (RT) and down pumping pitched blade turbine (PBTD). These two impellers were used
in two different sizes: T/2 and T/3 (where T is the inner tank diameter). Different hydrodynamic
conditions were generated by changing the hydrodynamic parameters such as power per mass
(P/ρV), Reynolds number, impeller tip speed (πND) and Weber number. The effect of these
different hydrodynamic conditions on the Pickering emulsion production was determined by
droplet size analysis. The Malvern Mastersizer 3000 equipment was used for measurements.
According to results of these analyses, it was observed that the RT T/2 impeller produced the
smallest droplets in baffled tanks. In unbaffled tanks, the best results were obtained when the
shaft was 2 cm away from the center with the RT T/3 impeller
Temporal dynamics in alpine snowpatch plants along a snowmelt gradient explained by functional traits and strategies
No full textAlpine snowpatches are characterised by persistent snow cover, short growing seasons and periglacial processes, which has resulted in highly specialised plant communities. Hence, these snowpatch communities are among the most threatened from climate change. However, temporal dynamics in snowpatch microclimate and plant composition are rarely explored, especially in the marginal alpine environments of Australia. Seven snowpatches were categorised into early, mid and late snowmelt zones based on growing season length, with soil temperatures recorded from 2003 to 2020 and plant composition surveyed in 84 1 m2 quadrats in 2007, 2013 and 2020. Microclimate, species diversity, plant cover and composition, along with community-weighted trait means and plant strategies were assessed to understand snowpatch dynamics in response to climate change. We found that growing season length and temperatures have increased in late melt zones, while changes were less consistent in early and mid melt zones. There were few changes in species diversity, but increases in graminoids and declines in snowpatch specialists in mid and late melt zones. Community-weighted plant height, leaf area and leaf weight also increased, particularly in mid and late melt zones, while plant strategies shifted from compositions of ruderal-tolerant to stress-tolerant. Here, we show that snowpatch communities are rapidly changing in response to longer growing seasons and warmer temperatures, with the greatest changes occurring where snow persists the longest. The results highlight the climate-induced loss of defining biotic and abiotic characteristics of snowpatches, as temporal convergence of compositions along snowmelt gradients threatens the distinctiveness of snowpatch plant communities.No Full Tex
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