scholarly journals Land snail dispersal, abundance and diversity on green roofs

2019 ◽  
Author(s):  
Michael L. McKinney ◽  
Nicholas S. Gladstone ◽  
Jillian G. Lentz ◽  
Faith A. Jackson

AbstractWe present the first major systematic study of land snail diversity on green roofs. We surveyed 27 green roofs and the adjacent ground habitat in six major cities in the southeastern United States. We found a total of 18 species of land snails, with three considered to be non-native, invasive species. The majority of land snails encountered in surveys are widespread, generalist species, typically adapted to open habitats. Twelve of the land snails encountered are “greenhouse” species that are very commonly transported via the horticultural trade. Therefore, we infer that at least some land snail species are introduced to green roofs via initial green roof installation and associated landscaping. Additionally, some similarity between roof and ground populations indicates dispersal from nearby ground habitats. The major determinants of snail species diversity and community composition are largely derived from local environmental conditions that are significantly correlated to the quality of green roof maintenance regime and plant diversity. Roof area, height, and age are seemingly not significant characteristics that dictate land snail species richness.

2014 ◽  
Vol 20 (1) ◽  
pp. 94 ◽  
Author(s):  
Gilianne Brodie ◽  
Gary M Barker ◽  
Froseann Stevens ◽  
Monifa Fiu

In May 2012 Rotuma Island, the main island of the remote Rotuma Group (Fiji), was surveyed to document the composition of the non-native land snail fauna and to investigate if populations of previously recorded native land snail species persist. From sampling at nine locations, twenty-one land snail species from eleven gastropod families were found. Of these, eight species are non-native and two of these Parmarion martensi Simroth, 1893 and Quantula striata (Gray, 1834) (Ariophantidae) are new records for the Rotuma Group. Ten of the 13 species of native land snails found — including the endemic partulid Partula leefi E. A. Smith, 1897 and the rhytidid Delos gardineri (E. A. Smith, 1897) — were detected only as empty shells. The native Ouagapia perryi (E. A. Smith, 1897) and the endemic Succinea rotumana E. A. Smith, 1897 and Sinployea rotumana (E. A. Smith, 1897) remain undetected on Rotuma Island since their first collection in 1897. The non-native, invasive predatory flatworm, Platydemus manokwari, was also found and represents a major threat to the island’s land snail fauna. This non-native species appears to be absent in many other parts of the Fiji Island archipelago and thus a re-evaluation of existing quarantine measures is required to address its potential spread to non-invaded areas. Comparisons with earlier surveys indicate a shift in the structure of the Rotuman land snail fauna over a 115-year period, with declining native components and increasing prevalence of non-native species. Further sampling, focusing on residual native habitat in less accessible areas such as coastal cliffs and offshore islets, is urgently needed to establish the conservation status of Rotuman native land snails and determine the threat posed by both, non-native snails and P. manokwari.


2015 ◽  
Vol 282 (1804) ◽  
pp. 20143063 ◽  
Author(s):  
Kazuki Kimura ◽  
Satoshi Chiba

Several taxa of simultaneously hermaphroditic land snails exhibit a conspicuous mating behaviour, the so-called shooting of love darts. During mating, such land snail species transfer a specific secretion by stabbing a mating partner's body with the love dart. It has been shown that sperm donors benefit from this traumatic secretion transfer, because the secretions manipulate the physiology of a sperm recipient and increase the donors' fertilization success. However, it is unclear whether reception of dart shooting is costly to the recipients. Therefore, the effect of sexual conflict and antagonistic arms races on the evolution of traumatic secretion transfer in land snails is still controversial. To examine this effect, we compared lifetime fecundity and longevity between the individuals that received and did not receive dart shooting from mating partners in Bradybaena pellucida . Our experiments showed that the dart-receiving snails suffered reduction in lifetime fecundity and longevity. These results suggest that the costly mating behaviour, dart shooting, generates conflict between sperm donors and recipients and that sexually antagonistic arms races have contributed to the diversification of the morphological and behavioural traits relevant to dart shooting. Our findings also support theories suggesting a violent escalation of sexual conflict in hermaphroditic animals.


2019 ◽  
Vol 85 (3) ◽  
pp. 311-318
Author(s):  
Birte Wendebourg ◽  
Bernhard Hausdorf

Abstract We investigated the land snail fauna of the Panguana conservation area on the western rim of the Amazonas basin in Peru. A total of 2,322 individuals assigned to 65 land snail species were collected in 32 plots. Ten additional species were found in collections made on previous expeditions to Panguana. On the basis of available data, Panguana is the most species rich locality for land snails in South America. The species density of 75 land snail species in c. 2 km2 of rather homogeneous rainforest is also high on a global scale. The land snail fauna of Panguana is characterized by a very high proportion of species belonging to the carnivorous family Scolodontidae, many of which are likely to be new to science. The fauna includes seven species that are new records for Peru, and the species Hirtudiscus sp., Xenodiscula venezuelensis, Geostilbia aperta, Guppya gundlachii and Thysanophora plagioptycha represent genera not previously recorded from the country. The synanthropic species Allopeas gracile, Opeas hannense, Subulina octona, Geostilbia aperta and Gastrocopta servilis form an ecologically distinct group that occurs mainly in sites strongly modified by humans. The presence of these species on the margin of the Amazon rainforest is evidence of the ongoing homogenization of the global fauna.


2011 ◽  
Vol 493-494 ◽  
pp. 287-292 ◽  
Author(s):  
D. Kel ◽  
Hasan Gökçe ◽  
D. Bilgiç ◽  
D. Ağaoğulları ◽  
I. Duman ◽  
...  

There are thousands of land snail species, ranging in size from 1 mm to the Giant African Snail growing up to a foot long. Two species, known as escargot, helix aspersa and helix pomatia, are commercially important. Helix pomatia is abundant in Turkey. Those snails are exported usually without shells. Shells are damped to trash sites or used as substitute food for animals. The shell is rich in calcium carbonate and some other minor minerals. Thus, snails’ shells can be used as a source for bioceramic production. So far, in the literature there are lot of papers about converting calcite and aragonite structures to hydroxyapatite (HA), like corals, sea shells, sea urchin and other sea creatures. However, there is very limited information about converting land snail shells to HA and other bioceramic phases. The aim of this work was to produce various phases of bioceramic materials from land snails’ shells which are left as a residue waste after their export procedures. Empty local land snails’ shells (helix pomatia) were collected in Istanbul. They were washed, dried, crushed and ball milled until a powder of 100 µm particles size was obtained. Raw powders were stirred at 80°C for 15 min on a hotplate. A second part of the raw powder was stirred with an ultrasonic stirrer at 80°C for 15 min in an ultrasonic equipment. Equivalent amount of H3PO4 was added drop by drop into the solution. The reaction lasted for 8h. Then, to evaporate the liquid part, the mixtures were put into an incubator at 100°C for 24 h and the resultant dried sediments were collected. The produced powders were analyzed with X-ray diffraction, IR and scanning electron microscope (SEM). The experimental results confirmed the formation of various Ca-phosphates, specifically monetite, fluorapatite and some other minor calcium phosphate phases. Bioceramic production from land snail is a reliable and economic way comparing to other tedious methods of producing synthetic HA and other various bioceramics phases.


2019 ◽  
Vol 20 (1) ◽  
pp. 130-139 ◽  
Author(s):  
Xie Haowen ◽  
Wu Yawen ◽  
Wang Luping ◽  
Luo Weilin ◽  
Zhou Wenqi ◽  
...  

Abstract Green roofs are a sustainable, low-impact development technique. They can reduce peak stormwater runoff and runoff volume and improve the quality of runoff from individual buildings and developments, which can lower the risk of frequent urban flooding and improve the quality of receiving waters. Few studies have compared different types of green roof models under the same rainfall intensities; thus, in this study, the predictions of a non-linear storage reservoirs model, Storm Water Management Model (SWMM), and a physical process model (HYDRUS-1D) were discussed. Both models were compared against measured data obtained from a series of laboratory experiments, designed to represent different storm categories and rainfall events. It was concluded that the total runoff of the SWMM model is always less than that of HYDRUS-1D. The maximum flowrate of the SWMM model is more than that of HYDRUS-1D during all events.


2012 ◽  
Vol 81 (3) ◽  
pp. 167-S1 ◽  
Author(s):  
Xavier Santos ◽  
Vicenç Bros ◽  
Elisabet Ros

Land-use change is considered the main disturbance in landscape structure and composition, directly affecting faunal distribution and species richness worldwide. Wildfires and natural reforestation alter habitat structure in terms of vegetation cover and also in soil composition and moisture; these processes hence trigger habitat transformations that act as opposing forces at small spatial scales. We have explored the contrasting effects of wildfires and natural reforestation on two land-snail species of the genus Xerocrassa, which are endemic in the western Mediterranean. Snails were sampled in pine and Holm oak forest, stony bare slopes and burnt sites. Both species followed a similar pattern: they were present in more than 75% of the stony bare slope sites and around 50% of the burnt sites, but were almost absent in Holm oak forests. The comparison of aerial photographs from 1956 and 2003 showed that stony bare slopes were significantly larger in 1956, this indicating that the natural reforestation might close these habitats, and consequently threaten the viability of the Xerocrassa populations. Given their limited mobility, the presence of Xerocrassa at burnt sites suggests that these species live in small and cryptic populations within the forest, surviving fire and expanding their distribution due to the appearance of adequate habitats. Our study shows that natural reforestation and fire play opposing roles in conserving Xerocrassa populations. The preservation of stony bare slopes as well as other open areas is a key management guideline to maintain landscape mosaics and help future conservation of species of open habitats such as these vulnerable endemic gastropods.


Zoo Indonesia ◽  
2020 ◽  
Vol 28 (1) ◽  
Author(s):  
Ayu Savitri Nurinsiyah ◽  
Ita Faizah ◽  
Yogi Prasetio ◽  
Tedi Setiadi ◽  
Ristiyanti Marsetiowati Marwoto ◽  
...  

The land snail fauna of the largest tropical montane forest in Java, the Gunung Halimun Salak National Park (GHSNP), was surveyed during the dry season (June-July) in 2015, concentrating on four park’s resorts, i.e. Cikaniki, Mt. Botol, Cisarua (Halimun area) and Cidahu (Salak area). In total, 399 specimens representing 43 species were collected. Prior to the surveys, 48 land snail species were known from the GHSNP. Fifteen new records for the GHSNP were discovered so 63 species are now known to inhabit the Park. This number represent 25% of the total land snail fauna of Java. 21 of the species found in GHSNP are endemic to Java. The species richness of the plots in GHSNP was correlated with soil pH and the composition of the land snail communities was correlated with elevation, annual mean temperature, and amount of deadwood.


2021 ◽  
Author(s):  
Thomas Schatzmayr Welp Sá ◽  
Mohammad K Najjar ◽  
Ahmed W A Hammad ◽  
Elaine Garrido Vazquez ◽  
Assed Naked Haddad

Abstract The shortage of water worldwide is increasingly worrying. Studies in the field suggest that sustainable water resource management via water recycling is fundamental to alleviate the issue. The use of rainwater is an important alternative source that must be considered, mainly, in the water crisis facing the planet. When integrated with the concept of green roofs, the capturing and treatment of rainwater in these structures becomes an even more ecological and sustainable practice. The water drained by the roof can be used for non-potable uses, such as flushing toilet bowls. One of the main concerns when using rainwater, even for non-potable uses, is the quality of the water available, so as not to put users' health at risk. In this way, the present work proposes to experimentally analyze the quality of rainwater drained in a green roof prototype for reuse purposes. The green roof prototype was installed on an experimental bench. After each rain event (four in total), two water samples were collected in the following situations: rainwater captured directly by a container next to the bench, and rainwater drained by the green roof prototype, captured by a container through existing drains at the base of the prototype. The analyzes of the collected samples were carried out at the Environmental Engineering Laboratory (LEMA / UFRJ) and performed according to the Standard Methods for the Examination of Water and Wastewater. Specifically, the experiments examine physicochemical and biological parameters following a rain event on a green roof prototype for sanitary use. Experimental results that were observed and analyzed include color, turbidity, pH, ammonia nitrogen, nitrite, nitrate, orthophosphate, total coliforms, and thermotolerant coliforms to indicate the rainwater quality from green roofs. The majority of parameters assessed were within the value thresholds indicated by the Brazilian standards, while the results of orthophosphate, fecal coliforms, color, and turbidity were not. The greatest divergence is in the concentration of orthophosphate, where a concentration of 10.88mg/L was obtained in this experimental study while other authors present values ​​of 0.1 and 0.01mg/L. Total coliforms also presented high values, but within the expected range. Comparisons with technical documents and international references related to water quality to identify possibilities of the use of rainwater were also conducted. Results indicate that the water quality has the same order of quantity for turbidity, nitrite, and ammonia nitrogen parameters across the standards. Based on such observations, filtration and disinfection processes are therefore required in the green roof system for the use of rainwater for sanitary. Finally, the experimental study of rainwater quality on the green roof presented similar results comparing with international references. The use of green roofs combined with the use of rainwater demonstrates the potential and benefits as an alternative to face the water crisis.


Water ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 94
Author(s):  
Bernardo Rocha ◽  
Teresa A. Paço ◽  
Ana Catarina Luz ◽  
Paulo Palha ◽  
Sarah Milliken ◽  
...  

Green roofs can be an innovative and effective way of mitigating the environmental impact of urbanization by providing several important ecosystem services. However, it is known that the performance of green roofs varies depending on the type of vegetation and, in drier climates, without resorting to irrigation, these are limited to xerophytic plant species and biocrusts. The aim of this research was therefore to compare differently vegetated green roofs planted with this type of vegetation. A particular focus was their ability to hold water during intense stormwater events and also the quality of the harvested rainwater. Six test beds with different vegetation compositions were used on the roof of a building in Lisbon. Regarding stormwater retention, the results varied depending on the composition of the vegetation and the season. As for water quality, almost all the parameters tested were higher than the Drinking Water Directive from the European Union (EU) and Word Health Organization (WHO) guidelines for drinking-water quality standards for potable water. Based on our results, biocrusts and xerophytic vegetation are a viable green roof typology for slowing runoff during stormwater events.


Oryx ◽  
2021 ◽  
pp. 1-6
Author(s):  
Wallace M. Meyer ◽  
Lily M. Evans ◽  
Connor J.K. Kalahiki ◽  
John Slapcinsky ◽  
Tricia C. Goulding ◽  
...  

Abstract The Hawaiian archipelago was formerly home to one of the most species-rich land snail faunas (> 752 species), with levels of endemism > 99%. Many native Hawaiian land snail species are now extinct, and the remaining fauna is vulnerable. Unfortunately, lack of information on critical habitat requirements for Hawaiian land snails limits the development of effective conservation strategies. The purpose of this study was to examine the plant host preferences of native arboreal land snails in Puʻu Kukui Watershed, West Maui, Hawaiʻi, and compare these patterns to those from similar studies on the islands of Oʻahu and Hawaiʻi. Concordant with studies on other islands, we found that four species from three diverse families of snails in Puʻu Kukui Watershed had preferences for a few species of understorey plants. These were not the most abundant canopy or mid canopy species, indicating that forests without key understorey plants may not support the few remaining lineages of native snails. Preference for Broussaisia arguta among various island endemic snails across all studies indicates that this species is important for restoration to improve snail habitat. As studies examining host plant preferences are often incongruent with studies examining snail feeding, we suggest that we are in the infancy of defining what constitutes critical habitat for most Hawaiian arboreal snails. However, our results indicate that preserving diverse native plant assemblages, particularly understorey plant species, which facilitate key interactions, is critical to the goal of conserving the remaining threatened snail fauna.


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