Guest editorial/gasskrywersrubriek: The role of the wildlife society in environmental conservation

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South African grassland ecology and its restoration

The aim of this study is to investigate how human related disturbances affect mesic grasslands. I identified what was lost from the system after a disturbance and what biological constraints ecologists and managers will face when approaching their restoration. I then investigated biological limitations to grassland restoration by attempting species reintroduction into secondary grasslands and exploring the interaction between grasses and forbs

Sustainable Practices in International Chain Hotels in Muscat, Sultanate of Oman

Purpose of the study The aims of the study were to analyze the sustainable practices adopted by international chain hotel brands in Muscat; to analyze and find out the extent of the sustainable practices affecting guest satisfaction in international chain hotels in Muscat and to determine the barriers and challenges faced by international hotel chain brands in Muscat. Design/Methodology/Approach Forty questionnaires were distributed to two chain hotels’ employees in different job positions. In-depth interviews were also used to gather qualitative information from human resources departments and corporate social responsibility specialists to discuss the current trends in sustainable practices in international chain hotel brands in Muscat.   The collected data was then analyzed using SPSS and Qualitative tools. Findings The study reveals that the hotels’ sustainability initiatives had an effective impact on cost savings and helps to reduce waste, and resource wastage. It was also found that guests are willing to pay more at the hotel to support their green initiatives and the guests were satisfied with the innovation towards the sustainability initiatives undertaken and felt their stay a memorable one. Research Implications It was observed that there is a strong relationship between sustainable green practices and guest satisfaction and so maintain the sustainable practices to raise up to the guest expectations. Some of the guests were not aware of the sustainable practices and the employees and the creation of awareness is a must. Practical Implications Awareness within the staff and the community can be raised only through proper education and training. Originality The study confines to international chain hotels located in Muscat, the capital of Sultanate of Oman. The study excludes the economic and social aspects of sustainability as the entire focus was on the environmental aspects of sustainable practices only

How successful is grassland restoration after removal of pine plantations on the eastern shores of Lake St Lucia?

The coastal grasslands that occur along the Eastern Shores of Lake St. Lucia are rich in plant species, including endemics. These grasslands in North KwaZulu-Natal, South Africa, are remnants of a severely threatened vegetation type. Large portions of the Eastern Shores have been utilized for commercial pine plantations over the last 50 years; however these have been removed over the last 17 years. It is therefore important that efforts to restore grasslands that have been previously afforested stands of pines are successful. These grassland systems are fire driven and therefore many plants have adapted to these conditions by having massive storage organs below the ground. Using several response variables I was able to assess the effects of plantations on alpha- and beta-diversity and functional traits of forb and other grassland species and attempted to determine whether these disturbed grassland were returning to their original state. A high level of community heterogeneity was found at both scales for natural vegetation, while more homogenous, species low patterns were seen in post-plantation sites. Most notable was the large number of missing resprouting species in pine sites and that, in contrast to forest rehabilitation studies, no evidence for succession was found. The implication of this is massive as grassland rehabilitation may be a lot harder than was previously thought. It is likely that the fire adapted forb species are bad colonizers and have struggled to return to disturbed sites. These grasslands are therefore susceptible to activities that remove or eliminate the considerable amount of below ground biomass from the soil, and these sorts of disturbances should be avoided. Active rehabilitation methods will be required if any progress is going to be made and until such methods are effective considerable effort should be made in conserving the remaining grasslands that we have left and promoting its pharmaceutical, horticultural and societal value

South Africa's spatial development initiatives : the case of the Lubombo SDI and the Greater St Lucia Wetland Park.

Thesis (M.T.R.P.)-University of KwaZulu-Natal, Durban, 2005A varied literature has emerged assessing the history and principles of the SDI programme and its individual initiatives. Within the literature, a widespread critique has developed that views the SDIs as falling short in two crucial areas. First, the SDIs have, in general, had limited developmental impacts . Second, many of the initiatives failed to develop adequate institutional responses to the specific conditions they faced in their various localities. The study describes the Lubombo SDI and its anchor project, the Greater St Lucia Wetland Park. It argues that the Lubombo SDI, from the outset, took institutions seriously with a long view of development. It did not seek to deliver large-scale investment in a short period. Rather, it focused on shifting the development fundamentals - including key aspects of the Lubombo region's institutional arrangements - and concentrating its resources on facilitating a major project capable of pulling the various agencies with a stake in the region's development onto a common platform. This concentration of effort, and the creation of a dedicated authority with a clear statutory mandate to promote development and conservation, has brought advances to an area where development was effectively blocked for many years. But the dynamic nature of the institutional environment remains a key challenge affecting the GSLWP and the execution of the Authority's mandate. The ability of the Authority to continue mediating the multiple tensions and complexities affecting the GSLWP will be crucial if the agenda first set by the Lubombo is to be carried forward in the coming years.Pagination (5-7)incorrec

Differential metamorphic effects on nitrogen isotopes in kerogen extracts and bulk rocks

This work was financially supported by a NASA Exobiology grant to RB (# NNX16AI37G), an NSF graduate student research fellowship to JZ, and a NASA postdoctoral fellowship to EES.The last decade has seen a steady rise in the number of publications on nitrogen isotopes in sedimentary rocks, which have become an established tool for investigating the evolution of life and environmental conditions. Nitrogen is contained in sedimentary rocks in two different phases: bound to kerogen or substituted in potassic minerals (mostly K-bearing phyllosilicates and feldspars). Isotopic measurements and interpretations typically focus either on kerogen extracts alone or on bulk rocks that include both phases. The community is split about which sample type more accurately captures the original composition of the biomass. To address this question, we combined nitrogen isotopes and carbon-to-nitrogen ratios with carbon-to-hydrogen ratios which act as an independent proxy for metamorphic alteration. Our results reveal that metamorphism drives kerogen-bound nitrogen isotopically lighter while silicate-bound nitrogen becomes heavier. For rocks up to greenschist facies, the isotopic effect of this internal partitioning (up to 3-4‰) is larger than the isotopic effect of metamorphic nitrogen loss from the system (up to 1-2‰). The opposite may be true for higher metamorphic grades. We conclude that for low-grade sedimentary rocks with more than 60% of their total nitrogen residing in the silicate phase the primary isotopic composition of the biomass is best approximated by the bulk rock measurement, whereas for high-grade rocks the kerogen extract may be the more accurate proxy. The isotopic difference between nitrogen phases can thus serve as a rough indicator of the degree of metamorphic alteration.PostprintPeer reviewe

Friedrich Heinrich Jacobi: O Spinozinu nauku u pismima Mosesu Mendelssohnu / Spisi o sporu o božanskim stvarima i njihovoj objavi

Understanding how and when Earth's surface became oxygenated is essential for understanding its biogeochemical evolution. Incipient oxygenation of Earth's surface environments before the Great Oxidation Event (GOE; 2.4 Ga) has been well-documented, but the nature of these redox changes, whether protracted or transient, is poorly understood. We present nitrogen isotope ratios, selenium abundances, and selenium isotope ratios from the Jeerinah Formation (2.66 Ga; Fortescue Group, Western Australia) that represent (i) high-resolution evidence of transient surface ocean oxygenation 260 My before the GOE, (ii) a possible muted pulse of oxidative continental weathering, and (iii) the oldest firm evidence for nitrification and denitrification metabolisms. These results, in concert with previous studies, highlight the variability in mechanisms and magnitudes of Neoarchean oxygen fluctuations.Many paleoredox proxies indicate low-level and dynamic incipient oxygenation of Earth's surface environments during the Neoarchean (2.8textendash2.5 Ga) before the Great Oxidation Event (GOE) at 2.4 Ga. The mode, tempo, and scale of these redox changes are poorly understood, because data from various locations and ages suggest both protracted and transient oxygenation. Here, we present bulk rock and kerogen-bound nitrogen isotope ratios as well as bulk rock selenium abundances and isotope ratios from drill cores sampled at high stratigraphic resolution through the Jeerinah Formation (2.66 Ga; Fortescue Group, Western Australia) to test for changes in the redox state of the surface environment. We find that both shallow and deep depositional facies in the Jeerinah Formation display episodes of positive primary δ15N values ranging from +4 to +6textperthousand, recording aerobic nitrogen cycling that requires free O2 in the upper water column. Moderate selenium enrichments up to 5.4 ppm in the near-shore core may indicate coincident oxidative weathering of sulfide minerals on land, although not to the extent seen in the younger Mt. McRae Shale that records a well-documented textquotedblleftwhifftextquotedblright of atmospheric oxygen at 2.5 Ga. Unlike the Mt. McRae Shale, Jeerinah selenium isotopes do not show a significant excursion concurrent with the positive δ15N values. Our data are thus most parsimoniously interpreted as evidence for transient surface ocean oxygenation lasting less than 50 My, extending over hundreds of kilometers, and occurring well before the GOE. The nitrogen isotope data clearly record nitrification and denitrification, providing the oldest firm evidence for these microbial metabolisms.PostprintPeer reviewe

Natural history of HFE simple heterozygosity for C282Y and H63D: A prospective 12-year study

Background and Aim - The risk of hemochromatosis-related morbidity for HFE simple heterozygosity for either the C282Y or H63D substitutions in the HFE protein was assessed using a prospective community-based cohort study. Methods - HFE genotypes were measured for 31 192 persons of northern European descent, aged between 40 and 69 years when recruited to the Melbourne Collaborative Cohort Study, and subjects were followed for an average of 12 years. For a random sample of 1438 participants stratified according to HFE genotype, two sets of biochemical iron indices performed 12 years apart and, at follow-up only, the presence/absence of six disease features associated with hereditary hemochromatosis were obtained. Summary data for 257 (139 female) C282Y simple heterozygotes and 123 (74 female) H63D simple heterozygotes were compared with 330 (181 female) controls with neither HFE mutation. Results - At baseline, mean transferrin saturation (TS) (95% confidence interval) and prevalence of TS > 55% were 35.14% (33.25, 37.04) and 3/112 (3%), 33.03% (29.9, 36.15) and 0/39 (0%), and 29.67% (27.93, 31.4) and 3/135 (2%) for C282Y, H63D and wild-type male participants, respectively. At follow-up, mean TS levels remained similar to baseline levels for both men and women irrespective of simple heterozygosity for either mutation. No HFE C282Y or H63D simple heterozygotes had documented iron overload (based on hepatic iron measures or serum ferritin greater than 1000 mg/L at baseline with documented therapeutic venesection). Conclusion - No documented iron overload was observed for HFE simple heterozygotes for either C282Y or H63D, and morbidity for both HFE simple heterozygote groups was similar to that of HFE wild-type participants

Development and Validation of an In Silico Decision Tool To Guide Optimization of Intravenous Artesunate Dosing Regimens for Severe Falciparum Malaria Patients

Most deaths from severe falciparum malaria occur within 24 h of presentation to a hospital. Intravenous (i.v.) artesunate is the first-line treatment for severe falciparum malaria, but its efficacy may be compromised by delayed parasitological responses. In patients with severe malaria, the life-saving benefit of the artemisinin derivatives is their ability to clear circulating parasites rapidly, before they can sequester and obstruct the microcirculation. To evaluate the dosing of i.v. artesunate for the treatment of artemisinin-sensitive and reduced ring stage sensitivity to artemisinin severe falciparum malaria infections, Bayesian pharmacokinetic-pharmacodynamic modeling of data from 94 patients with severe malaria (80 children from Africa and 14 adults from Southeast Asia) was performed. Assuming that delayed parasite clearance reflects a loss of ring stage sensitivity to artemisinin derivatives, the median (95% credible interval) percentage of patients clearing ≥99% of parasites within 24 h (PC24≥99%) for standard (2.4 mg/kg body weight i.v. artesunate at 0 and 12 h) and simplified (4 mg/kg i.v. artesunate at 0 h) regimens was 65% (52.5% to 74.5%) versus 44% (25% to 61.5%) for adults, 62% (51.5% to 74.5%) versus 39% (20.5% to 58.5%) for larger children (≥20 kg), and 60% (48.5% to 70%) versus 36% (20% to 53.5%) for smaller children (<20 kg). The upper limit of the credible intervals for all regimens was below a PC24≥99% of 80%, a threshold achieved on average in clinical studies of severe falciparum malaria infections. In severe falciparum malaria caused by parasites with reduced ring stage susceptibility to artemisinin, parasite clearance is predicted to be slower with both the currently recommended and proposed simplified i.v. artesunate dosing regimens