Permanent Water Sources Research Articles

Late Pleistocene hominin settlement patterns and population dynamics in the Zagros Mountains: Kermanshah region

The Middle and Upper Palaeolithic artifacts of the Zagros Mountains are relatively better understood than those in other parts of the Iranian Plateau. However, settlement systems, land use and Palaeolithic population dynamics for this region have received less attention. Here we present research on the study of human behavior that contributes to a better understanding of the early human colonization of Eurasia. Specifically, we focus on the Kermanshah region of the west-central Zagros to evaluate hominin dispersal and adaptation by investigating hominin settlement patterns and behavioral responses to the new and diverse environments and topography of this part of the Zagros region. Our survey in Kermanshah documented over 260 new Palaeolithic localities, enabled us to draw Middle and Upper Palaeolithic site distribution patterns and population dynamics which reveal that this part of the Zagros was intensively populated in both the Middle and Upper Palaeolithic. This research demonstrates that the Zagros in general, and the Kermanshah area in particular, were by no means impassable but include intermountain plains connected to each other by valleys associated with permanent water and raw material sources. Middle Palaeolithic settlements are most abundant in areas with high topographic contrast that contain high mountains, flat plains, and diverse resources. Eventually, the Zagros was one of a handful of important interglacial refugia in south-western Asia for hominins during the Upper Pleistocene and may have served as a core area from which colonizations and recolonizations of Eurasia occurred during multiple dispersals.

Archaeobotany of Aboriginal plant foods during the Holocene at Riwi, south central Kimberley, Western Australia

Riwi, a limestone cave located in the south central Kimberley, northwest Western Australia, has one of the most accurately dated archaeological sequences in Australia, with human occupation beginning between 46,400 and 44,600 cal bp. Macrobotanical remains are well preserved at the site, particularly in upper stratigraphic units 1 and 2 dated to the late and mid-Holocene, respectively. Macrobotanical materials (excluding wood charcoal) are uncommon in Pleistocene contexts, and direct dating of some of the macrobotanical remains recovered from Pleistocene hearths suggest that they derive from the directly superposed Holocene layers. Analysis of the macrobotanical remains from the Holocene layers reveals a pattern where Aboriginal groups occupying Riwi intermittently between 7,000 years ago and the present principally exploited monsoon rainforest ecosystems for food plants, especially Vitex cf. glabrata. Fruiting times of dominant monsoon rainforest taxa indicate that the site was occupied seasonally, corresponding with periods of rainfall when people were able to move away from rivers and other permanent water sources. Results demonstrate a strong cultural preference for fruits associated with monsoon rainforest—a vegetation type restricted in distribution—highlighting the importance of moisture retaining limestone outcrops in foragers’ subsistence organisation in the south central Kimberley.

Landscape‐scale habitat response of African elephants shows strong selection for foraging opportunities in a human dominated ecosystem

Balancing trade‐offs between foraging and risk factors is a fundamental behavior that structures the spatial distribution of species. For African elephantsLoxodonta africana, human pressures from poaching and conflict are primary drivers of species decline, but little is known about how elephants structure their spatial behavior in the face of human occupancy and predation. We seek to understand how elephants balance trade‐offs between resource access, human presence and human predatory risk factors (poaching and conflict killing) in an unfenced, dynamic ecosystem where elephants persist primarily outside protected areas in community rangelands. We used tracking data from 101 elephants collected between 2001 and 2016. We investigated elephant behavior in response to landcover, topography, productivity, water, human features and human predation risk using third‐order resource selection functions. We extended this analysis by employing a mixed‐effects multinomial regression to identify temporal shifts in habitat use, and evaluated temporal shifts in movement patterns by estimating mean squared displacement across different productivity periods. Across periods, elephants displayed strong selection for productive areas and areas near water. Temporal shifts in habitat use showed that, during the dry period, elephants were clustered around permanent water sources where humans also congregated. At the onset of the wet period, a shift occurred where elephants moved away from permanent water and from permanent settlements towards seasonal water sources and seasonal settlements. Our findings indicate that foraging and water access are important limiting factors affecting elephants that potentially restrain their spatial responses to humans at the scale of our analysis. Given that pastoralists and elephants rely on the same resources, increasing human and livestock populations enhance pressure on shared resources and space in Africa's drylands. The long‐term conservation of elephants will require approaches that reduce poaching as well as landscape level planning to prevent negative impacts from increasing competition for preferred resources.

The land malacofauna from Vesuvius National Park and neighbouring areas (Naples, Southern Italy): Preliminary results

The faunistic data on the recent land molluscs of Vesuvius National Park (Naples, Southern Italy) and neighbouring areas sampled during field surveys from 2005 to 2006 are reported here. The data were obtained through a careful research on museum collections and literature and were supplemented with observations from field surveys. Up to now, only 23 land snails species were known from the Vesuvius National Park through bibliographical data. The faunistic research, carried out in 25 stations of different environment typologies, allowed us to discriminate 31 species: 15 of these species are reported here for the first time for the study area. The presence of 16 species was confirmed by other field investigations. Other 19 taxa are reported in the literature, but not confirmed in our research - Helix turriculatella O. G. Costa, 1839 (obsolete nomenclature), Trochoidea trochoides Poiret, 1789, Hygromia cinctella (Draparnaud, 1801), Campylaea planospira (Lamarck, 1822), Vitrea sp. (cf. contracta (Westerlund, 1871)), Cecilioides acicula (O. F. Müller, 1774), Cochlicella acuta (O. F. Müller, 1774), Theba pisana O. F. Müller, 1774). Another 12 taxa are highly doubtful, because of possibilities for confusion with species living in other European or Italian regions, as well as previous misidentifications (Deroceras agreste (Linnaeus, 1758), Monacha gregaria (Rossmässler, 1839), Cochlicella barbara (Linnaeus, 1758), Monachoides incarnatus (O. F. Müller, 1774),Cernuella (Cernuella) cisalpina (Rossmässler, 1837), Cernuella aradasii (Pirajno, 1842), Oxychilus cellarius (O. F. Müller, 1774), O. alliarius (J. S. Miller, 1822), Zonitoides nitidus (O.F. Müller, 1774), Hyalina pseudohydatina, Ferussacia lubrica, Aegopinella nitens (Michaud, 1831); it was impossible in these cases to refer to their current specific name. Eobania vermiculata (O. F. Müller, 1774), Rumina decollata (Linnaeus, 1758), Papillifera papillaris (O. F. Müller, 1774) appear to be the most common species. Interesting are the records of Marmorana muralis (O.F. Müller, 1774), Helix cf. ligata (O.F. Müller, 1774) and Charpentiera gibbula gibbula (Rossmässler, 1836). Charpentieria gibbula honii (Tiberi, 1878) needs genetic investigations in order to confirm its taxonomic status. One allochthonous species (Paralaoma servilis (Shuttleworth, 1852)) was surveyed for the first time in the study area. A Red List of Threatened Species is proposed and the species are classified according to the IUCN criteria (Version 2019-2.1). The malacofauna of Vesuvius - Somma Mountain Complex is composed by 38 land mollusc species and represents 36.2% of the total species present in Campania (about 105 species, personal data) and 12.8% of the Italian fauna (about 530 species of land molluscs extrapolated from the list of Bank (2017). It is assumed that the poor biodiversity of the Vesuvian land malacofauna can be attributed essentially to the scarcity of calcareous substrates and the absence of permanent water sources.

Ecological constraints associated with genome size across salamander lineages.

Salamanders have some of the largest, and most variable, genome sizes among the vertebrates. Larger genomes have been associated with larger cell sizes, lower metabolic rates, and longer embryonic and larval durations in many different taxonomic groups. These life-history traits are often important for dictating fitness under different environmental conditions, suggesting that a species' genome size may have the potential to constrain its ecological distribution. We test how genome size varies with the ephemerality of larval habitat across the salamanders, predicting that species with larger genomes will be constrained to more permanent habitats that permit slower development, while species with smaller genomes will be more broadly distributed across the gradient of habitat ephemerality. We found that salamanders with larger genomes are almost exclusively associated with permanent aquatic habitats. In addition, the evolutionary transition rate between permanent and ephemeral larval habitats is much higher in salamander lineages with smaller genome sizes. These patterns suggest that genome size may act as an evolutionary constraint on the ecological habitats of salamanders, restricting those species with large genomes and slower development to habitats with permanent sources of water.

Overlapping landscape utilization by elephants and people in the Western Okavango Panhandle: implications for conflict and conservation

Many wildlife populations exist outside of protected areas, and it is necessary to understand how these animals use a landscape mosaic that includes humans. Patterns of landscape use in space and time can help inform strategies to mitigate negative interactions between people and wildlife. We aimed to estimate the landscape utilization of elephants where they ranged through a mosaic of human-modified land-use and undisturbed habitat to better understand spatial implications for human-wildlife interactions. We studied locations and utilization distributions of ten bull elephants in the Western Okavango Panhandle region of Botswana. We calculated utilization distributions, patterns of landscape use, and daily movement relative to permanent water and human land-use. The annual distributions of the monitored elephants ranged from 1220 to 3446 km2 and showed seasonal variation, with wet season distributions being significantly larger than dry season distributions. On average 49.4% of elephants’ core distributions in the dry season and 12.3% in the wet season fell within 5 km of human land-use. Elephants ranged increasingly farther from permanent water sources as the wet season progressed, while in the same time frame elephants moved closer on average to human land-use. Elephants were more likely to be near human land-use during the night than they were during the day. Diel patterns of elephant proximity to human land-use did not match patterns of proximity to water. Conservation and management efforts must consider the diel and seasonal patterns of elephant movement in order to fully address the issue of human-elephant interactions.

Peritidal stromatolites as indicators of stepping-stone freshwater resources on the Palaeo-Agulhas Plain landscape

Natural sources of freshwater are a limiting feature to the distribution of terrestrial species that rely on regular hydration, especially in coastal environments. Early modern humans would similarly be restricted by water supply and likely would have congregated or settled in close proximity to permanent water bodies such as beyond the estuarine extent of large rivers. However, along the modern south coast of southern Africa, for example, distances between freshwater from rivers can exceed what would be convenient daily walking limits. In the absence of alternative water supply, or a means of water storage, these distances would preclude human settlement beyond river borders. Recent discovery of living peritidal stromatolites forming along the southern South African coastline suggests a potential alternative water source. These unique ecosystems form only at locations where groundwater rich in calcium carbonate meets periodic marine intrusion along the coastal margin. Calcium carbonate is precipitated by cyanobacteria and sediment is trapped by diatoms, primarily, to form layered deposits that preserve into the fossil record. Critical to the formation and growth of these stromatolites is a fresh, uninterrupted supply of groundwater. During their growth, the peritidal stromatolites accumulate and retain this freshwater through the formation of rimstone dams and barrage pools at the seaward margin of neocoastal geological outcrops. Recognising the presence of permanent water sources other than rivers for early humans is challenging; however, these stromatolites provide a clear signature of an alternative water resource. Here we review the modern prevalence of peritidal stromatolites in this region, of which approximately 540 are known along a 200 km stretch of South Africa's southern coastline featuring only 11 estuaries. This is linked to features (cf. rimstone dams and barrage pools) resembling peritidal stromatolites in the adjacent Palaeo-Agulhas Plain landscape using multibeam echosounder and side-scan sonar data and contextualised as a possible water resource for early modern humans.

Occupancy dynamics of semi‐aquatic herbivores in riparian systems in Illinois, USA

AbstractStreams and local riparian habitats are a product of the landscapes they drain. Consequently, aspects of the landscape, as well as local stream morphology, are likely to affect riparian and stream communities, including occupancy of semi‐aquatic mammals. To gain a better understanding of how changing landscapes may affect the occupancy of semi‐aquatic mammals, we sought to identify aspects of the riparian system and stream structure at multiple scales that relate to the presence of beaver (Castor canadensis) and muskrat (Ondatra zibethicus), including their interactions with mink (Neovison vison) and river otter (Lontra canadensis). We estimated multi‐season occupancy using 103 sites sampled over six seasons (2012–2014) in southern Illinois, USA. We hypothesized beaver and muskrat occupancy was related to multiple aspects of landscape and local habitat including land‐cover, water availability, human disturbance, stream characteristics, and the presence of other semi‐aquatic mammals. Beaver occupancy varied over time and was predicted by stream size, stream density, and land‐cover at the landscape scale. Muskrat occupancy also varied over time and was related to local aspects of habitat including percentage of forest in the riparian area, channel incision, land‐cover, and aspects of sediment chemistry. Our results indicate the importance of spatial and temporal variation, scale, and food and water availability for these semi‐aquatic species. Beaver and muskrat are most likely to be affected by changes to water regimes including availability of permanent water sources due to changing landscapes.

Seasonal patterns of gas exchange and water relations in juveniles of two Neotropical savanna tree species differing in leaf phenology

Ecophysiological studies on Neotropical savanna trees have shown that there is a resistance gradient of seasonal water stress in deciduous and evergreen species. Some species perform like drought avoiders, characterized by high transpiration rates during the wet season that can be sustained by evergreen deep rooted species during the dry season. Nevertheless, water deficit in superficial soil layers, fire damages and nutritional requirements could differentially affect juveniles of both phenological types determining their spatial patterns of distribution (evergreen species sparse in open grasslands and deciduous species gathered in groves). This study examined seasonal variations in water relations and photosynthesis in juveniles of two tree species differing in leaf phenology: Curatella americana (evergreen) and Cochlospermum vitifolium (deciduous). We wanted to test the hypothesis that the improved ability of evergreen deep rooted species like C. americana to colonize open savannas is related to drought tolerance and a conservative gas exchange pattern in juveniles that photosynthesize even during the dry season, while one might expect a water spender and avoider character in propagules of deciduous species like C. vitifolium that are active mostly during the rainy season. The studied species showed high transpiration rates during the rainy period, indicating little water availability limitations on surface soil layers. Even so, both species exhibited a distinctive decrease in stomatal conductance towards the end of the rainy season, an indication of water availability restrictions and/or a response to higher air evaporative demands in the shallow rooted juveniles. At the peak of the dry season, C. americana presented comparable transpiration rates with wet season measurements, indicating that the studied juveniles had reached more permanent (or stable) water sources at soil depths of 30 cm (approximate maximum root lengths measured). Yet, C. americana showed a significant decrease in water potentials from wet to dry seasons, and osmotic adjustment as a drought tolerance mechanism. Overall, the evergreen functional type (juvenile plants of C. americana) showed tolerance to water deficit, maintaining functional leaves in the dry season. On the other hand, in absence of a water deficit, juveniles of C. vitifolium showed higher photosynthetic rates that could be translated into high growth rates in wet habitats. However, the low water deficit tolerance of the juveniles of C. vitifolium seems to be the main handicap for its colonization potential of the open savanna environment. In conclusion, as predicted, the greater tolerance to water deficit of the evergreen studied species suggests that resistance to water stress determines the observed distribution pattern of tree species in the study area, where only the evergreen ones colonize the open savanna, acting in its adult stages as a focus for the recruitment of woody species.

Water relations of an insular pit viper

Colonization of novel habitats often requires plasticity or adaptation to local conditions. There is a critical need to maintain hydration in terrestrial environments having limited water. Atypical populations of Florida cottonmouth snakes, Agkistrodon conanti, inhabit continental islands with no permanent sources of fresh water. Here, we report investigations related to how these insular snakes maintain water balance considering the mainland conspecifics are semi-aquatic and typically associate with freshwater mesic habitats. We tested three hypotheses related to water relations of insular populations of cottonmouth snakes compared with those on the mainland. (1) Voluntary drinking of fresh water in free-ranging insular snakes should reflect a relationship to recency of rainfall more strongly than in mainland snakes. (2) Insular snakes will tolerate greater dehydration before drinking than will mainland snakes. (3) Insular snakes will avoid drinking seawater more strongly than will those from the mainland. Between 2001 and 2018, we quantitatively estimated the hydration status of 337 individual cottonmouth snakes from insular populations and 30 cottonmouth snakes from mainland Florida, as judged by the tendency of wild-caught snakes to drink fresh water immediately following capture. We found that insular cottonmouth snakes had a higher incidence of dehydration than did mainland cottonmouth snakes (64% versus 23%), and the hydration status of the insular snakes correlated with patterns of precipitation. We also determined experimentally the dehydration threshold for drinking fresh water in insular (mean±s.d. -5.64±4.3%, n=34) and mainland cottonmouth snakes (-5.74±4.5%, n=21), and these were not significantly different. Discrimination tests for drinking serially from a graded series of brackish water showed that mainland snakes did not discriminate against the highest brackish value (10.5ppt or 30% seawater), whereas insular snakes showed a preference for <15% seawater. Naive neonates from insular and mainland cohorts behaved similarly. The preference of insular snakes for fresh water represents an important aspect of the maintenance of water balance that differs from the mainland conspecifics and is likely a habituated or adaptive response to dependence on rainfall.

A novel solar photovoltaic system with pumped-water storage for continuous power at constant voltage

A novel off-grid small power generation system using locally available sources is proposed in this paper for the areas, where the open-wells or the permanent sources of water are available. Although, the system can be installed anywhere, but its installation in remote and rural areas, where there is no access of electricity, can be an interesting application. The proposed system comprises of a solar photovoltaic (SPV) system, solar water pump, pico-hydro turbine-generator and pumped-hydro energy storage system. Its operation is quite different from all other existing SPV power generating systems. In this paper, an innovative power generation technique is developed, due to which the output power of the proposed system is absolutely unaffected by the changes that occur in solar irradiation. The proposed system does not require the use of batteries, inverter, transformer, and charging or controlling circuits at all. The attractive features of the system are simplicity, reliability and ability to generate continuous power at constant voltage irrespective of variations or absence of solar irradiation. The mathematical model of the proposed system has been developed in the paper. The simulation is carried out using real solar irradiation for performance evaluation of the proposed model.

Imperial resource management at the ancient Maya city of Tikal: A resilience model of sustainability and collapse

Over the time span of more than a millennium, the ancient Maya polity of Tikal went through periods of growth, reorganization and adaptive cycles of various connected scales. Recent data show that following the reorganization of the Late Preclassic period, Tikal experienced an extended period of technological innovation and population growth that eventually stretched the carrying capacity of the available landscape. A hydraulic system was constructed that provided water for the community during the dry seasons: a powerful development in an area without a permanent water source. Agriculture was intensified using a combination of root crop agriculture, irrigated fields, arboriculture, household gardens, short fallow cropping systems and bajo margin cultivation. The net product of these diverse production activities helped to underwrite an enormous amassing of economic and political capital during the Late Classic period. Ultimately, in the mid-9th century CE, expansive growth combined with multiple system disturbances led to a collapse of the city’s social structure followed by abandonment of the site. The application of resilience theory as a conceptual framework is useful in helping to interpret the complex web of the underlying social and ecological domains that contributed to Tikal’s demise.

Precipitation patterns and hydration status of a unique insular snake population.

Water is essential to survival, and thus invasion of habitats having limitations of water necessitates adaptations to maintain water balance. Climate change is expected to alter precipitation patterns worldwide. A unique population of Florida cottonmouth, Agkistrodon conanti, inhabits Seahorse Key (SHK) near coastal Levy County, Florida where they are entirely terrestrial, scavenge fish carrion, and are without permanent sources of fresh water. Insofar as cottonmouths are generally associated with freshwater habitats, this insular population of snakes is likely to exhibit adaptations for living with limited resources, especially water. Our objective is to measure the hydration status in free‐ranging snakes to better understand the possible stresses related to dehydration. We hypothesize that hydration status of cottonmouths on SHK will follow patterns of precipitation. We tested dehydration and drinking behavior of cottonmouth snakes inhabiting SHK from 2001–2017. Snakes were captured and tested for thirst immediately following capture. They were provided access to fresh water for at least 12 hours while we noted drinking and weighed snakes before and after. Mass gains reflected drinking and therefore hydration status. These data were compared to satellite data for date of last rainfall event (peak &gt;2.5 mm/hr) preceding capture (NASA TRMM &amp; GPM). The percentage of captured cottonmouths found to drink was found to increase with an increase in the number of days since a rainfall event. Results support the prediction that hydration status of cottonmouths on SHK correlates with rainfall patterns, suggesting that snakes rely on periodic rainfall to remain hydrated. Insular cottonmouth populations are of conservation concern as annual precipitation rates have declined over the past century and may continue to decline due to climate change.Support or Funding InformationU.S. Fish &amp; Wildlife Service, Sigma Xi, Chicago Herpetological Society, &amp; SSARThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Access to Water and Awareness about the Unsafe Water in Rural Bangladesh

Introduction: Access to drinking water is a fundamental concern for many countries, including Bangladesh. Drinking of unsafe water might result to cause diseases and illness which heightens the economic burden for every one by increasing the treatment costs and work days lost. In Bangladesh, rural households coupled with the lack of safe water, also faces water-contamination with arsenic and other pollutants. Objective: This study explores the status of the rural people in accessing the water for households. It also determines their knowledge regarding the contaminated water. Methodology: The current study used retrospective data from Bangladesh Rural Advancement Committee’s (BRAC) Research and Evaluation Division’s baseline survey which was initiated under the ‘water, sanitation and hygiene’ program. Data was taken from 16,052 households between November 2006 and June 2007. Descriptive statistics were used to report the study findings. Results: Approximately 67% of the households had a permanent water source and majority had their deep tube well. A major proportion of the household respondent (70%) identified the method properly to purify polluted water. About 41% households used tube well as a source of water for daily purposes, i.e., drinking, cooking, washing utensils, and bathing. Majority (85%) of the households were found to pay willingly for a good source of water. Households with the non-governmental organization (NGO) membership were willing to pay even more for the safe water as compared to households without NGO membership. Conclusion: Respondents had considerable knowledge and awareness concerning the contaminated water. The association of NGO membership and level of awareness presented in this study should be of particular interest to the policy makers. Keywords: Health, Awareness, Knowledge, Rural Bangladesh.

Stone Age landscape use in the Olifants River Valley, Clanwilliam, Western Cape, South Africa

ABSTRACTStone Age surface assemblages are all too often neglected in favour of stratified, datable cave sequences, thus overlooking important insights into changing behavioural patterns at a broader scale. The Olifants River Valley (Clanwilliam, Western Cape Province, South Africa) presents a rich surface lithic record alongside excavated rockshelter occupations from the early Middle Stone Age (MSA) to the Later Stone Age (LSA). Surface surveys in the Olifants River Valley mapped temporally diagnostic artefacts and their association with different topographic features in order to investigate past landscape use. Our approach refers to a hypothesis proposed by Hilary Deacon, framing the MSA within the context of earlier and later patterns of behaviour. Based on observations from sites across South Africa, Deacon described Earlier Stone Age (ESA) landscape use as ‘stenotopic’, with a narrow focus on permanent water sources, and LSA landscape use as ‘eurytopic’, using a much broader range of habitats but specifically occupying rockshelters as domestic sites. Deacon suggested that the intervening MSA, in its later stages, shows a pattern that anticipated LSA landscape use. We apply Deacon's model to the study area, observing distinctive preferences for certain locations and raw materials and approaching changing patterns of artefact discard from a technological perspective.

An empirical test of the role of learning in translocation

AbstractTranslocation centers on the introducing, reintroducing, or augmenting populations by moving individuals from existing wild source populations to different locations with purportedly suitable habitat. Despite much research in and application of translocation, this technique is often marred by low success rates. While many possible factors could contribute to low translocation success, outcomes are often improved when researchers engage in a soft release, which provides the animals with the opportunity for extra time to acclimate to their release site, indicating that aspects of learning may play an important role in translocation success. To test the importance of the time available for learning in translocation success, we performed hard and soft releases into an existing population of Eastern painted turtles Chrysemys picta that has experienced seasonal ephemeral water sources and in which resident turtles navigate to new permanent sources of water with extreme precision (±3.5 m) using specific routes known to be facilitated by learning. Translocated adult turtles in both hard‐ and soft‐release groups failed to successfully negotiate upland habitat, even when given 3 months to prospect and learn (the maximum time possible in our system). Likewise, turtles in both groups moved more slowly, stopped more frequently, and were slower to restart movement than resident adults. Finally, both translocated groups exhibited significant drops in body mass and elevated rates of predation. In contrast, juveniles from the same donor population navigated to alternative water successfully, with movements and mortality rates not different from resident animals. These results indicate that complex aspects of cognition beyond time to learn can influence translocation success and highlight the importance of considering how and when animals learn.

Spatial refuges buffer landscapes against homogenisation and degradation by large herbivore populations and facilitate vegetation heterogeneity

Environmental heterogeneity across savanna landscapes, including different seasonal resources at different distances to water, may play a critical role in maintaining the size and diversity of wildlife populations and the sustainability of their resource base. We investigated whether extensive landscapes with functionally diverse seasonal resources and large waterless regions can mediate the effect of herbivory on plant composition, structure and diversity. Vegetation composition, structure and richness in two different vegetation types (mopane and sandveld woodland) at three distance zones (0 km – 5 km, 10 km – 15 km and &gt; 20 km) from the permanent water of the Okavango Delta and Linyanti Swamps were surveyed. We modelled vegetation response of the most abundant species to herbivory in relation to distance from permanent water, and included fire frequency as a covariate. Trees favoured by elephants during the dry season occurred typically as immature, pollarded populations within 5 km of permanent water sources while mature tall populations of these species were found far from water (&gt; 10 km – 15 km). Similarly, short high-quality grazing grasses were higher in abundance within 5 km of permanent water, whereas taller high-quality perennial grasses peaked in abundance beyond 20 km from permanent water. Trends in herbaceous richness with distance from water were contingent upon vegetation type, while tree richness did not change with distance from water. Spatial refuges in waterless regions of landscapes facilitate the creation of heterogeneity of vegetation structure, composition and richness by large herds of mammalian herbivores. Therefore, the extension of herbivore dry season foraging range, for example, by the creation of artificial water points (AWP) in backcountry woodlands, could seriously undermine the resilience of landscapes to herbivory by reducing the availability of spatial refuges. Consequently, it reduces the resilience of herbivore and predator populations that depend on these spatial refuges. We strongly advise that future scientific work, and management and policy actions should be focused on the identification and sustaining of these spatial refuges in wildlife areas.Conservation implications: Management and policy actions should be focused on the identification and sustainability of spatial refuges in wildlife areas. Too many AWP in backcountry woodlands could undermine the resilience of landscapes to herbivory by reducing the proportion of landscapes beyond 15 km from permanent water.

Online appendix 1:Spatial refuges buffer landscapes against homogenisation and degradation by large herbivore populations and facilitate vegetation heterogeneity

Environmental heterogeneity across savanna landscapes, including different seasonal resources at different distances to water, may play a critical role in maintaining the size and diversity of wildlife populations and the sustainability of their resource base. We investigated whether extensive landscapes with functionally diverse seasonal resources and large waterless regions can mediate the effect of herbivory on plant composition, structure and diversity. Vegetation composition, structure and richness in two different vegetation types (mopane and sandveld woodland) at three distance zones (0 km – 5 km, 10 km – 15 km and &gt; 20 km) from the permanent water of the Okavango Delta and Linyanti Swamps were surveyed. We modelled vegetation response of the most abundant species to herbivory in relation to distance from permanent water, and included fire frequency as a covariate. Trees favoured by elephants during the dry season occurred typically as immature, pollarded populations within 5 km of permanent water sources while mature tall populations of these species were found far from water (&gt; 10 km – 15 km). Similarly, short high-quality grazing grasses were higher in abundance within 5 km of permanent water, whereas taller high-quality perennial grasses peaked in abundance beyond 20 km from permanent water. Trends in herbaceous richness with distance from water were contingent upon vegetation type, while tree richness did not change with distance from water. Spatial refuges in waterless regions of landscapes facilitate the creation of heterogeneity of vegetation structure, composition and richness by large herds of mammalian herbivores. Therefore, the extension of herbivore dry season foraging range, for example, by the creation of artificial water points (AWP) in backcountry woodlands, could seriously undermine the resilience of landscapes to herbivory by reducing the availability of spatial refuges. Consequently, it reduces the resilience of herbivore and predator populations that depend on these spatial refuges. We strongly advise that future scientific work, and management and policy actions should be focused on the identification and sustaining of these spatial refuges in wildlife areas.Conservation implications: Management and policy actions should be focused on the identification and sustainability of spatial refuges in wildlife areas. Too many AWP in backcountry woodlands could undermine the resilience of landscapes to herbivory by reducing the proportion of landscapes beyond 15 km from permanent water.

Aspects of the home range ecology of the leopard tortoise in the semi-arid central Karoo: An area threatened with fracking

Whilst fracking is used globally, impact studies on wildlife are limited. The semi-arid Karoo, South Africa, a large ecosystem with a high degree of endemism, is targeted for fracking. We investigated how adult leopard tortoises (Stigmochelys pardalis) use their environment by determining individual and seasonal variation in home range and effects of weather factors on these pre-fracking. Data were obtained from Global Positioning System (GPS) transmitters placed on leopard tortoises (n = 11) on private livestock farms near Beaufort West, South Africa for a year. Kernel density estimation (KDE) was used to estimate home range. Individuals had a mean (±SE) home range of 121.86 ± 28.12 ha, (range 40.53–258.52 ha) with a core area of 76.55 ± 17.33 ha (range 21.22–83.89 ha). No difference was found between annual male and female home ranges. Two telemetered individuals were excluded from analysis because they exhibited apparent nomadic behaviour. Several individuals did not visit permanent water sources, possibly suggesting that dietary water intake was sufficient. Generalised Linear Mixed Models were used to explain monthly home range estimates (95% KDEhref) in regards to biologically significant predictor variables. A single top model (ΔAICc < 2) was produced, indicating importance of individual variability (sex, body mass) and weather (temperature, rainfall) variables. Our results provide baseline data pre-fracking in the region, and as such, should be repeated following commencement of fracking.

Metals, heavy metals and microorganism removal from spent filter backwash water by hybrid coagulation-UF processes

Abstract Spent filter backwash water (SFBW) reuse has attracted particular attention, especially in countries that experience water scarcity. It can act as a permanent water source until the water treatment plant is working. In this study, the concentrations of Fe, Al, Pb, As, and Cd with total and fecal coliform (TC/FC) were investigated in raw and treated SFBW by hybrid coagulation-UF processes. The pilot plant consisted of pre-sedimentation, coagulation, flocculation, clarification, and ultrafiltration (UF) units. Poly-aluminum ferric chloride (PAFCL) and ferric chloride (FeCl3) were used as pretreatment. The results showed that, at the optimum dose of PAFCl, the average removal of TC and FC was 88 and 79% and with PAFCl-UF process, it reached 100 and 100%, respectively. For FeCl3, removal efficiency of TC and FC were 81 and 72% and by applying FeCl3-UF process, it reached 100 and 100%, respectively. In comparison with FeCl3, PAFCl showed better removal efficiency for Fe, Pb, As, and Cd, except residual Al concentration. Coagulation-UF process could treat SFBW efficiently and treated SFBW could meet the US-EPA drinking water standard. Health risk index values of Fe, AL, Pb, AS, and Cd in treated SFBW indicate no risk of exposure to the use of this water.