Decomposition and arthropod succession on buried remains during winter and summer in central South Africa: forensic implications and predictive analyses

English: While burial is utilised by criminals as a means of disposing of a body, knowledge of the impact it has on arthropod succession and decomposition within South Africa is currently lacking. The study was conducted within a 24 hectare grassland field, located on the University of the Free State grounds. A total of seven pig carcasses (Sus scrofa Linnaeus) were utilised for each of the two seasonal trials, with six of them being buried in randomly spaced graves at depths of 60cm and one placed above-ground as a control. Each of the graves was excavated on predetermined days over each 60 day trial to minimise disturbance and evaluate the impact of differing time periods on decomposition and arthropod succession. After its initial excavation, grave one was excavated every third day until the conclusion of the trial to determine the impact of disturbance on buried remains. Decomposition and biomass loss progressed faster on buried carcasses compared to aboveground during the winter season. A faster rate of decomposition and biomass loss was seen for the above-ground carcass versus the below-ground carcass during the summer season, mainly due to heavy rainfall causing waterlogging of the graves. Between the two seasons, a higher decomposition and biomass loss rate was recorded on the summer buried carcasses compared to those buried in winter. Dipteran species were seen to dominate on the summer control carcass, while, during the winter trial, the coleopteran species, Dermestes maculatus De Geer (Dermestidae), was noted to extensively colonise and outcompete present dipteran individuals. With cold, dry climatic conditions leading to the winter control carcass undergoing a form of mummification, adult D. maculatus individuals were seen to congregate on the carcass and reproduce, leading to larval aggregation during the active decay stage. During the trials, only dipteran species were found to colonise the winter buried carcasses, whereas the summer buried carcasses w
Afrikaans: Alhoewel misdadigers dikwels van „n liggaam ontslae raak deur dit te begrawe, is relatief min bekend oor die impak daarvan op arthropoodsuksessie en die ontbindingsproses in Suid- Afrika.. Die studie het plaasgevind op „n 24-hektaar grasland op die gronde van die Universiteit van die Vrystaat. Sewe varkkarkasse (Sus scrofta Linnaeus) is gedurende elk van die twee seisoenale proefperiodes gebruik, waarvan ses op „n diepte van 60cm op ewewydige afstande van mekaar begrawe is en een bogronds gelos is as die kontrole. Begraafte karkasse is opgegrawe op spesifieke voorafbepaalde tye oor die 60 dae van die proeftydperke en sodoende is verseker dat versteuring tot „n minimum beperk is terwyl die impak van „n grafomgewing op arthropoodsuksessie en ontbinding vasgestel is. Na die aanvanklike opgrawing van die eerste graf, was die graf vervolgens elke derde dag opgegrawe tot aan die einde van die proefperiode om die impak van versteuring te evalueer. Ontbinding en biomassa-verlies het „n vinniger tempo getoon vir karkasse wat begrawe was, teenoor die bo-grondse karkas gedurende winter. „n Vinniger tempo van ontbinding en biomassa-verlies was vir die bo-grondse karkas getoon in vergelyking met die begraafde karkasse gedurende die somer, hoofsaaklik as gevolg van die swaar reën wat veroorsaak het dat die grafte deurdrenk geraak het. Vir die twee seisoene was „n vinniger tempo van ontbinding en biomassa-verlies gedurende die winter vir die begraafde karkasse ondervind. Diptera-spesies was, getalle gewys, in die meerderheid op die kontrole-karkas tydens die somer, maar gedurende die winter het „n Coleoptera-spesie, Dermestes maculatus De Geer (Dermestidae) tot so „n mate oorheers dat die besetting deur Diptera-spesies minimaal was. As gevolg van die koue, droë klimaatstoestande wat daartoe aanleiding gegee het dat die winter kontrole-karkas „n vorm van mummifikasie ondergaan het, is volwasse D. maculatus indivudië na die karkas aangetrek en voortplanting het tot larwal