Ecology

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Anthropogenic impacts on forest mammals in the Southern Mistbelt Forests in the Midlands of KwaZulu-Natal, South Africa = Imithelela ye-Anthropogenic Ezilwaneni Ezincelisayo Ehlathini Emahlathini Anezinkungu Angaseningizimu Maphakathi neKwaZulu-Natali, ENingizimu Afrikha
(2023) Cordier, Craig Paul.; Downs, Colleen Thelma.; Ehlers Smith, David Alan.; Ehlers Smith, Yvette Cathrine.
Habitat loss worldwide is a major threat to biodiversity. Forest loss is affected by numerous factors, including natural climate change and anthropogenic disturbances (e.g., logging, habitat conversion or increased fire activity). Forest fragmentation results in reduced patch sizes, increased edge effects, and connectivity between patches negatively impacted. Forest fragmentation effects on species differ, with some considerably more sensitive to these changes than others, often resulting in their local extinction. By monitoring biodiversity, effective conservation measures can be implemented to conserve the biodiversity in these forests. Remote camera traps have become an increasingly popular tool to study wildlife in a reliable, non-invasive way. Firstly, the use of camera traps as a research tool in Africa using a systematic review was determined. This highlighted the countries with studies that used camera traps the most, as well as determined the terrestrial wildlife and habitat types receiving the most focus. The findings from assessing camera trap research in Africa revealed that most studies were conducted in South Africa, with most studies focusing on the occupancy of mammals, with a particular focus being on large carnivores, the majority of which were leopard Panthera pardus. Most studies were conducted in forests, followed by savannah/bushveld. Secondly, the presence of forest mammalian species was assessed in the Southern Mistbelt forests in the Midlands of KwaZulu-Natal, South Africa. These forests are fragmented because of both natural and anthropogenic factors. An extensive camera trapping survey was conducted between October 2020 and April 2021 (wet season), and between May 2021 and September 2021 (dry season), with 14 indigenous forest patches being sampled. A total of 339 camera trap stations were deployed in this study, with microhabitat conditions, in a 20 m radius around each camera trap, collected to determine their impact on bushbuck Tragelaphus scriptus, a diurnal forest specialist, and Cape porcupine Hystrix africaeaustralis, a nocturnal generalist, and how the microhabitat conditions potentially impacted their occupancy between the austral wet and dry seasons. Bushbuck were the most recorded mammalian species recorded during both seasons. Cape porcupine presence was recorded more during the dry season, with various microhabitat variables influencing their occupancy. Cape porcupines, as generalists, likely use the forest food resources during the dry season. Bushbuck presence was lower in state-owned forests, likely because of the hunting activities observed in these forests. Thirdly, data collected from the camera trapping surveys were used to determine the influence of landscape factors, including patch size, landscape configuration (number of neighbouring patches), and patch isolation (distance from mainland patch), on forest mammalian species diversity in forest patches, between the wet and dry seasons. Patch size strongly influenced forest mammalian species richness, which was relatively low, with more species occupying larger patches than smaller patches. Similarly, landscape configuration affected species richness and was generally higher in those forests surrounded by multiple forest patches. Forest isolation, however, did not seem to be particularly impactful in determining forest mammalian species diversity. Overall, this research showed the value of camera traps as a research tool and their effectiveness in studying rare and elusive mammalian species in Africa. Effects of anthropogenic disturbances on various forest mammalian species were highlighted, with activities such as hunting and uncontrolled resource harvesting, such as collection of fuelwood, medicinal plants and building materials by the local communities, impacting the presence of various forest mammalian species, particularly forest specialist species, such as the blue duiker Philantomba monticola. The importance of maintaining small forest patches, often considered of low conservation value, was highlighted. These act as essential ‘stepping stones’ between forest patches, allowing species to traverse a landscape mosaic. The need for conservation measures not to disregard the importance of these small forest patches is emphasised, as they are vital assets to maintain species richness in landscape mosaics with forest patches. Iqoqa. Ukuphela kwamahlathi kubangwa izimo eziningi, okubalwa kuzo ukuguquka kwesimo sezulu okuyimvelo kanye nokuphazamiseka ngenxa yezimo ezidalwa ngabantu. Ngokwengamela impiliswanomvelo, ukubhekana nokugcineka okuyimpumelelo kungasetshenziswa ukugcina impiliswanomvelo kula mahlathi. Izicupho zesithwebuli esikude seziphenduke ithuluzi elidume kakhulu ukucwaninga izilwane zasendle ngendlela eyethembekile, enganyakazi yonke indawo. Okokuqala, ukusebenzisa izicupho zesithwebuli njengethuluzi lokucwaninga e-Afrikha kusetshenziswa ukubuyekezwa okuhlelekile kwatholakala. Imiphumela yaveza ukuthi ucwaningo lwesicupho sesithwebuli lwenziwa eNingizimu Afrikha, nocwaningo oluningi lugxile ekuhlalisekeni kwezilwane esincelisayo, nokugxila okuqondile ezilwaneni ezinkulu ezidla inyama. Ucwaningo oluningi lwenziwa emahlathini, lulandelwa olwenziwa ehlane/enkangala. Okwesibili, ukuba khona kwezinhlobo zezilwane ezincelisayo kwahlolwa Emahlathini Anezinkungu Angaseningizimu Maphakathi neKwaZulu-Natali, eNingizimu Afrikha. La mahlathi ahlukene phakathi ngenxa yezimo zemvelo kanye nezimo ezidalwa ngabantu. Iseveyi yesicupho sesithwebuli yenziwa ngesikhathi semvula kanye nesikhathi sokoma kwezulu, ngokusampula izichibi zamahlathi endabuko eziyi-14. Inani elingama-339 lezindawo zesicupho sesithwebuli zafakwa kulolu cwaningo, nezimo zezindawana zokuhlala ezizungeze isicupho sesithwebuli ngasinye kwaqoqwa ukuthola umthelela wazo kwi-Tragelaphus scriptus yenkangala, abahlali jikelele bansukuzonke, kanye nengungumbane yaseKapa i-Hystrix africaeaustralis, abahlali jikelele basebusuku, kanye nokuthi lezi zimo zingaba namthelela muni ekuhlalekeni kwazo phakathi kwezikhathi zonyaka. Unkonka waba uhlobo lwesilwane esincelisayo esaqoshwa kakhulu ngezikhathi zombili zonyaka. Ubukhona bengungumbane yaseKapa kwaqoshwa kakhulu ngesikhathi sonyaka sokoma kwezulu, ngamavarebhuli ezindawana zokuhlala ehlukene anomthelele ekuhlaleni kwazo. Izingungumbane zaseKapa, ngengabahlali jikelele, anokusebenzisa izidlo zehlathi ngezikhathi zokoma kwezulu. Ubukhona bukankonka kwakuphansi emahlathini abanikazi bawo kunguhulumeni, njengokuthi kungenxa yokuzingela okwenzekayo lapho. Okwesithathu, imininingo eyaqoqwa kumaseveyi esicupho sesithwebuli yasetshenziswa ukuthola umthelela wezimo zendawo, okubalwa kuzo ubungako bezichibi, phakathi kwezikhathi zonyaka zemvula kanye nezomile. Ubungako besichibi baba nomthelela omkhulu ekudlondobaleni kohlobo lwezilwane ezincelisayo, ngezinhlobo eziningi ezihlala ezichibini ezinkulu zehlathi. Ngokufanayo, umklamo wendawo onomthelelea ekudlondlobaleni lwezinhlobo zezilwane futhi wabe uphezulu kulawo mahlathi azungezwe izichibi eziningana zehlathi. Ukuzimela kwehlathi, noma kunjalo, akubonakalanga kunomthelela omkhulu ekutholeni umehluko wezinhlobo zezilwane zasehlathini ezincelisayo.
Community diversity and composition of ground-dwelling arthropods in major habitat types of the KwaZulu-Natal Sandstone Sourveld.
(2023) Mhlongo, Nokukhanya.; Tsvuura, Zivanai.; Munyai, Thinandavha Caswell.
Grasslands constitute over 25% of the global land surface and close to one-third of southern Africa. Natural and semi-natural grasslands are recognized globally for their high biodiversity value and their important contribution to the provision of ecosystem services, including provisioning services such as carbon sequestration, water catchments, and grazing for livestock and wildlife. Nonetheless, grasslands are consistently reduced and threatened by anthropogenic activities and invasive alien plants. Invasive alien plants may hinder the growth of natural vegetation by overconsumption of resources. The impact of invasive alien plants on natural vegetation may indirectly affect plant-to-animal interactions such as specialized pollination and seed dispersal syndromes which may ultimately disturb ecosystem processes. The Sandstone Sourveld in KwaZulu-Natal province of South Africa is a threatened grassland ecosystem as a result of various anthropogenic disturbances. Knowledge of arthropod response to differences in habitat types may be essential for an improved understanding of the structure and functioning of ecosystems, which is relevant for informing conservation practice. The aim of this study was to investigate the composition and diversity patterns of ground-dwelling arthropods (ants, beetles, Orthopterans, and spiders) in three habitat types (forest, intact grassland, and disturbed grassland) at Springside and Tanglewood Nature Reserves, which occur in the KwaZulu-Natal Sandstone Sourveld (KZNSS). The objectives were: (i) to document the response of the ground-dwelling arthropod community in different habitat types, (ii) to determine the impacts of seasonal change on the abundance and richness of ground-dwelling arthropods at the two sites, and (iii) to determine the correlation between the distribution of ground-dwelling arthropods and soil characteristics in the KZNSS. Ground-dwelling arthropods were sampled in Springside and Tanglewood Nature Reserves using pitfall traps in each habitat type. Soil parameters in the habitats were also assessed. Analysis of variance was used to test for differences in arthropod morphospecies richness and abundance viii across the habitat types and between seasons. The Shannon-Weiner diversity index was computed and used to compare the diversity of ground-dwelling arthropods between the two sites and among habitat types. Ground-dwelling arthropods showed varying patterns in response to habitat characteristics and the disturbance gradient at Springside and Tanglewood. Intact grassland was the most diverse habitat in both Springside and Tanglewood. In Tanglewood, the abundance of ants was greater in disturbed grassland which consisted of a variety of alien invasive shrubs, the high abundance was explained by the “intermediate disturbance hypothesis”. However, alien invasion showed more negative than positive impacts on the abundance and composition of ground-dwelling arthropods when there was a significant decrease in the abundance and composition of ants, beetles and spiders. Species richness of ants and beetles was higher in the wet than dry season whereas Orthopterans and spiders showed no significant difference between seasons. In all arthropod groups, a greater number of species were correlated to soil potassium, soil pH, and soil bulk density. Overall, the intact grassland had the highest species richness and abundance followed by the forest and lastly the disturbed grassland. The greater abundance of ants, beetles, and spiders in the pristine grasslands of KZNSS shows that there is still a need to conserve the remnants of the KZNSS vegetation. Therefore, the conservancy management is urged to consider the eradication of alien invasive plants. Future studies are recommended to consider the volant and vegetation canopy arthropods as they are all interdependent with ground-dwelling arthropods to form a whole community of arthropods in an ecosystem.
Effects of landscape and forest structural characteristics on the avian communities in Southern Mistbelt Forests, Midlands of KwaZulu-Natal, South Africa = Imithelela yesimo sendawo kanye nezici zesakhiwo sehlathi emiphakathini yezinyoni e-Mahlathini Ezinkungu aseNingizimu, Maphakathi neKwaZulu-Natali, ENingizimu Afrikha.
(2023) Bitani, Nasiphi.; Downs, Colleen Thelma.; Ehlers Smith, David Alan.; Ehlers Smith, Yvette Cathrine.
Globally forest ecosystems are under threat from land-use changes threatening biodiversity. Biodiversity conservation in forest systems has become a major concern as these impacts affect ecosystem functioning. Habitat destruction results in highly fragmented forest patches with reduced habitat quality. Therefore, it is essential to assess species' responses to these changes for conservation. Like other parts of the world, South African forests are threatened by destruction, mainly habitat conversion to exotic commercial tree plantations. Forest bird species within this system have been reported to be declining. Considering these impacts, it is important to understand the main drivers at different spatial scales. This study aimed to assess local and landscape drivers of avian communities in the Southern Mistbelt Forests in the Midlands of KwaZulu-Natal, South Africa. The objectives were to assess (1) the local scale drivers and influences on bird species richness, use and functional diversity, (2) microhabitat requirements and occupancy of understorey forest specialist bird species using camera traps, and (3) landscape attributes influencing bird species richness, habitat use and functional groups. Firstly, the influence of forest structure and composition on bird species richness, habitat use and functional diversity in 14 selected Southern Mistbelt Forest patches of KwaZulu-Natal were assessed. The bird species were surveyed using point count surveys. Functional diversity for each surveyed patch was quantified using three indices: functional richness, functional evenness and functional divergence. Species-specific responses were assessed by focusing on three forest specialists, orange ground-thrush Geokichla gurneyi, forest canary Crithagra scotops, and Cape parrot Poicephalus robustus. Bird community and forest bird specialists' responses to forest structure and tree species diversity varied. Forest structural complexity, canopy cover, and tree species richness were the main structural characteristics influencing bird functional diversity. Also, forest composition and structure are important for bird species and functional richness. Secondly, the microhabitat requirements of forest specialist bird species using camera surveys in the selected 14 Southern Mistbelt Forests were assessed. The results showed that the microhabitat requirements of the understorey forest specialist species are specific. Occupancy models showed that forest specialist understorey birds are mainly influenced by tree species richness, understorey cover of leaf litter and water. Lastly, the bird species richness, habitat use and functional groups’responses to selective logging history, livestock grazing and adjacent matrix type were assessed. The bird communities were surveyed using point-counts. Functional diversity was quantified using functional richness, functional divergence and functional evenness estimated using bird functional traits. The disturbance did not affect bird species richness. Forest specialists' responses to disturbance were species-specific depending on the type of disturbance and intensity. The orange ground-thrush and forest canary were affected by livestock grazing, while the Cape parrot was influenced by forest logging history. Functional richness for all functional groups was high in disturbed forests, while functional evenness for forest specialists and insectivores was low in disturbed sites. The results of this study provide insight into the local and landscape drivers of avian species richness and diversity. Forest patches with high tree species diversity and structural complexity should be maintained to conserve forest specialists, bird species richness and functional richness. Also, to maintain the persistence of the understorey forest specialists, forest structures within 5 m of the forest floor should be maintained. It is recommended to use functional diversity indices with taxonomic indices to understand bird species responses to disturbance better. Iqoqa Emhlabeni wonke imvelo yamahlathi isengozini ngenxa yezinguquko zokusetshenziswa komhlaba ezisongela izinhlobonhlobo zezinto eziphilayo. Ukongiwa kwezinhlobonhlobo zezinto eziphilayo ezinhlelweni zamahlathi sekuyinkinga enkulu njengoba le mithelela ithinta ukusebenza kwe-ecosystem. Ukucekelwa phansi kwezindawo zokuhlala kubangela ukuba iziqephu zehlathi ezihlukene kakhulu ezinekhwalithi encishisiwe yendawo yokuhlala. Ngakho-ke, kubalulekile ukuhlola izimpendulo zezilwane kulezi zinguquko ukuze zilondolozwe. Njengezinye izingxenye zomhlaba, amahlathi aseNingizimu Afrikha asongelwa ukucekelwa phansi, ikakhulukazi ukuguqulwa kwezindawo zokuhlala zibe amasimu ezihlahla zentengiso ezingavamile. Izinhlobo zezinyoni zasehlathini kulesi simiso kuye kwabikwa ukuthi ziyancipha. Ngokucabangela le mithelela, kubalulekile ukuqonda abashayeli abakhulu ezilinganisweni ezahlukene zendawo. Lolu cwaningo beluhlose ukuhlola abashayeli bendawo kanye nemvelo bemiphakathi yezinyoni e-Southern Mistbelt Forests eMidlands KwaZulu-Natal, eNingizimu Afrikha. Izinjongo kwakuwukuhlola (Okokuqala) abashayeli bezinga lendawo kanye nomthelela ekunotheni kwezinhlobo zezinyoni, ukusetshenziswa kanye nokuhlukahluka kokusebenza, (Okwesibili) izimfuneko ze-microhabitat kanye nokuhlala kwezinhlobo zezinyoni ezichwepheshile zamahlathi angaphansi kusetshenziswa izicupho zamakhamera, kanye (Okwesithathu) nezici zezwe ezithonya izinhlobo zezinyoni. ukunotha, ukusetshenziswa kwendawo kanye namaqembu asebenzayo. Okokuqala, umthelela wesakhiwo samahlathi kanye nokwakheka kwawo ekunotheni kwezinhlobo zezinyoni, ukusetshenziswa kwezindawo zokuhlala kanye nokuhlukahluka kokusebenza kweziqephu eziyi-14 ezikhethiwe ze-Southern Mistbelt Forest KwaZulu-Natal. Izinhlobo zezinyoni zahlolwa kusetshenziswa inhlolovo yokubala amaphuzu. Ukwehlukahlukana kokusebenza kwesiqephu ngasinye esihloliwe kwalinganiswa kusetshenziswa izinkomba ezintathu: ukunotha kokusebenza, ukulingana kokusebenza kanye nokwehluka kokusebenza. Izimpendulo eziqondene nezinhlobo ezithile ziye zahlolwa ngokugxila kochwepheshe abathathu bamahlathi, i-orange ground-thrush i-Geokichla gurneyi, i-canary Crithagra scotops, kanye ne-Cape Parrot Poicephalus robustus. Izimpendulo zomphakathi wezinyoni kanye nezingcweti zezinyoni zasehlathini ezakhiweni zehlathi kanye nezinhlobonhlobo zezinhlobo zezihlahla ziye zahlukahluka. Ubunkimbinkimbi besakhiwo sehlathi, ukumboza kombhede, nokunotha kwezinhlobo zezihlahla kwakuyizici eziyinhloko zesakhiwo ezithonya ukuhlukahluka kokusebenza kwezinyoni. Futhi, ukwakheka kwehlathi nokwakheka kubalulekile ezinhlotsheni zezinyoni nokunotha kokusebenza. Okwesibili, izidingo ze-microhabitat zezinhlobo zezinyoni ezingochwepheshe behlathi ezisebenzisa izinhlolovo zamakhamera ku-14 Southern Mistbelt Forests ezikhethiwe zahlolwa. Imiphumela yabonisa ukuthi izidingo ze-microhabitat zezinhlobo zezingcweti zamahlathi angaphansi ziqondile. Amamodeli okuhlala abonise ukuthi izinyoni ezingochwepheshe bamahlathi zithonywa kakhulu ukunotha kwezinhlobo zezihlahla, ikhava engaphansi yodoti wamaqabunga namanzi. Okokugcina, ukunotha kwezinhlobo zezinyoni, ukusetshenziswa kwendawo yokuhlala kanye nezimpendulo zamaqembu asebenzayo emlandweni wokugawulwa kwemithi, ukudlelwa kwemfuyo kanye nohlobo lwe-matrix eseduze kwahlolwa. Imiphakathi yezinyoni yahlolwa kusetshenziswa ukubala amaphuzu. Ukwehluka kokusebenza kukalwe kusetshenziswa ukunotha kokusebenza, ukwehluka kokusebenza kanye nokulingana kokusebenza okulinganiselwe kusetshenziswa izici zokusebenza kwezinyoni. Ukuphazamiseka akuzange kuthinte ukunotha kwezinhlobo zezinyoni. Izimpendulo zochwepheshe bamahlathi ekuphazanyisweni zaziqondene nezinhlobo ezithile kuye ngokuthi hlobo luni lokuphazamiseka namandla. I-ground-thrush ewolintshi kanye ne-canary yasehlathini yaphazanyiswa ukudla kwemfuyo, kanti i-parrot yaseKapa yathonywa umlando wokugawulwa kwamahlathi. Ukunotha okusebenzayo kwawo wonke amaqembu asebenzayo kwakuphezulu emahlathini aphazamisekile, kuyilapho ukusebenza ngokulingana kochwepheshe bamahlathi kanye nezinambuzane kwakuphansi ezindaweni eziphazamisekile. Imiphumela yalolu cwaningo inikeza ukuqonda mayelana nabashayeli bendawo kanye nezwe lokunotha kwezinhlobo zezinyoni kanye nokwehlukahlukana. Iziqephu zehlathi ezinokwehlukahlukana kwezihlahla eziphakeme kanye nobunkimbinkimbi besakhiwo kufanele kugcinwe ukuze kugcinwe ongoti bamahlathi, ukunotha kwezinhlobo zezinyoni kanye nokunotha kokusebenza. Futhi, ukuze kugcinwe ukuphikelela kochwepheshe bamahlathi angaphansi kwesitezi, izakhiwo zehlathi ngaphakathi kwamamitha ama-5 ukusuka phansi kwehlathi kufanele zigcinwe. Kunconywa ukusebenzisa izinkomba zokuhlukahluka okusebenzayo ngezinkomba ze-taxonomic ukuze uqonde kangcono izimpendulo zezinhlobo zezinyoni ekuphazanyisweni.
Population assessment and conservation status of African lions (Panthera leo) = Ukuhlolwa kweqoqo lokuphilayo nesimo sokongiwa kwamabhubesi ase-Afrika (Panthera leo).
(2024) Nicholson, Samantha Karin.; Slotow, Robert Hugh.; Bauer, Hans.; Roxburgh, Lizanne.
For several decades, the lion (Panthera leo) has undergone significant population decline across its range. The aim of this dissertation was to critically assess the current conservation status of Africa’s most iconic carnivore. This included determining methods used to survey them, the conservation status of the global population, how fragile lion subpopulations are, and the perceived threats to the species across their African range. As with most carnivores, several survey methods have been developed to estimate lion population abundance. To assess the current state of lion survey methodologies, I conducted a systematic literature review of peer reviewed scientific publications. The strengths and weaknesses of each method were considered, as well as their reliability and applicability in determining abundance and distribution. Building on from how lions are surveyed, I used current data that are available to assess the current population and distribution of lions to produce the updated IUCN Red List Assessment (RLA). RLAs provide a standardised and comprehensive tool to evaluate the status of species, prioritise conservation efforts, and drive informed decision-making at the global, national, and local levels. Extant lion range was estimated to be ~1,571,296 km² - an estimated 36 % range decline since 2002 (three lion generations). Based on this significant decline in range, which is synonymous with a decline in population size and abundance, a 36 % decline in population numbers for the lions was suspected. Therefore, the species met the requirements for a Vulnerable listing (Red List criteria A2abcd). As effective species conservation is about more than just understanding how many there are, I, in collaboration with other experts in large carnivore conservation, examined the socio-political and ecological fragility (hereafter fragility: defined as a species vulnerability to extinction) of known lion populations. By combining ecological and socio-political metrics, an overall fragility index demonstrated which lion populations were more vulnerable to extinction. The analysis revealed several populations were highly fragile and lion populations in Somalia were the most fragile while those in Botswana are the least. Populations that had the highest fragility included Bush-Bush (Somalia) and Maze National Park (Ethiopia). As the RLA indicated that populations are declining, I sought to determine the severity of the existing anthropogenic threats to lions driving these declines. To do this, I conducted an online questionnaire of experts across lion range. A threat severity index was developed for each subpopulation, and I assessed how this varied between subpopulations and across regions. A resource availability index was also developed to identify lion subpopulations which are not sufficiently resourced (e.g., funding, anti-poaching equipment, vehicles). This allowed me to highlight populations that are perceived as highly threatened and that are under-equipped. I found the total threat index differed significantly among regions, being highest (i.e. most severe) in Central Africa and lowest (i.e. least severe) in southern Africa. Perceived resource availability was highest in Rwanda, Chad and Benin and lowest in six countries including Angola, Burkina Faso, Niger, South Sudan, Sudan and Uganda. This analysis identified how specific threats differ between regions. I offer valuable insights into the species' status and provide innovative recommendations that could enhance the management of lions across their range. This includes conservation interventions that target specific threats while incorporating socio-political and ecological factors which contribute to a population’s fragility. As lions remain listed as Vulnerable, and lion populations continue to decline, I recommend that the regional strategies be updated based on improved data and information available. To ensure that population data gathered and reliable and robust, harmonised survey methods need to be developed and implemented across the species range, especially in areas where survey data are poor or lacking. In a world where we are losing species at an unprecedented rate, effective and targeted conservation is needed, that is guided by the best available data, to ensure that the lion isn’t one of those species that disappears. Iqoqa. Emashumini ambalwa eminyaka, siye sehla kakhulu isibalo samabhubesi (iPanthera leo) kulona lonke uhlu lwezinhlobo. Inhloso yalolu cwaningo ukuhlola bekuwukuhlola ngokuhlaziya isimo samanje sokongiwa kwalezi zlwane ezidla inyama ezidume kakhulu e-Afrika. Lokhu kwakufaka ukuza nezindlela ezisetshenziswayo ukwenza uhlolo, isimo sokongiwa kwesibalo samabhubesi emhlabeni wonke, ukuthi amabhubesi antekenteke kangakanani, kanye nezinkinga ezicatshangwayo ezinhlobonhlobo kulona lonke uhlobo lwase-Afrika. Njengezilwane eziningi ezidla inyama, kuye kwasungulwa izindlela ezimbalwa zokuhlola ukulinganisa isibalo samabhubesi. Ukucwaninga ngesimo samanje sezindlela zokwenza uhlolo ngebhubesi, ngenze ukubuyekezwa kwemibhalo eyahlukahlukene ebhalwe ngabacwaningi abahlukene. Amandla nobuthaka bendlela ngayinye kwabhekwa, kanye nokwethembeka kanye nokusebenza kwezindlela lezo ekuhloleni ukwanda kanye nokusabalaliswa kwamabhubesi. Ukuqhubekela phambili endleleni amabhubesi ahlolwa ngayo, ngisebenzise imininingo yamanje ekhiqiziwe ukuze ngihlole isibalo samanje samabhubesi kanye nokusatshalaliswa kwawo ukuze kuvezwe izibalo eziqinisekisiwe ze-IUCN Red List Assessment (RLA). I-RLA ihlinzeka ngensizakusebenza evamisiwe nephelele yokuhlola isimo sezinhlobo zezinto eziphilayo, ukubeka kuqala imizamo yokongiwa kwemvelo, futhi aqhubekisele phambili ukuthathwa kwezinqumo okunolwazi emazingeni omhlaba, kazwelonke, nawendawo. Izinhlobo eziphilayo zamabhubesi zilinganiselwa e-1,571,296 km² - ukwehla okulinganiselwa kumaphesenti angama-36 kusukela ngonyaka wezi-2002 (ezizukulwaneni ezintathu zamabhubesi). Ngenxa yezibalo ezinkulu zokwehla kwesibalo samabhubesi, okufana nokwehla kwesibalo samabhubesi kanye nobuningi, kwaphawuleka ukwehla okungamaphesenti angama-36 kwezibalo zamabhubesi. Ngakho-ke, lolu hlobo lwamabhubesi lungathathwa njengolusengcupheni yokuphela (Kusetshenziswa indlela yokukala, i-A2abcd). Njengoba ukongiwa kwezilwane ngempumelelo kungaphezu nje kokuqonda ukuthi zingaki, mina, ngokubambisana nabanye ochwepheshe kwezokongiwa kwezilwane ezinkulu, ngahlola ubuthakathaka bezenhlalo nezombusazwe kanye nemvelo (ubuthakathaka obulandelayo: buchazwa njengendawo yokuba sengcupheni yokushabalala) kohlobo lwebhubesi olwaziwayo. Ngokubheka isimo senhlalo nesepolitiki, inkomba yengcuphe iyonke ibonise ukuthi yimaphi amabhubesi asengozini yokushabalala. Ucwaningo luveza ukuthi isibalo esimbalwa samabhubesi sisengcupheni kakhulu kanti amabhubesi eSomalia asengcupheni kakhulu uma eqhathaniswa nawaseBotswana. Izinhlobo ezisengcupheni enkulu kufaka iBush-Bush (eSomalia) kanye neMaze National Park (e-Ethiopia). Njengoba i-RLA ibonise ukuthi isibalo samabhubesi siyehla, ngazama ukuthola ubukhulu benkinga bokwehla kwesibalo samabhubesi nokuthi idalwa yini. Ukwenza lokhu, ngenze uhlu lwemibuzo olwathunyelwa ngezobuchwepheshe ukuthola ulwazi kulabo abangochwephese ngezinhlobo ezahlukene zamabhubesi. Uhlu lwezinkinga ngohlobo ngalinye lwamabhubesi lwenziwa futhi ngahlola ukuthi lokhu kwehluka kanjani phakathi kwezinhlobo ezahlukene kanye nasezifundeni ezahlukene. Uhlu ngokutholakala kwezinsiza nalo lwenziwa ukuze kuhlonzwe isibalo esincane sezindawo zamabhubesi anganazo izinsiza ezanele (isb., uxhaso lwezimali, izinto zokulwa nokuzingela ngokungemthetho, izimoto). Lokhu kungisizile ukuveza isibalo samabhubesi asengcupheni kakhulu futhi anganakekelwa ngendlela efanele. Ngithole ukuthi ubungcuphe obubhekene namabhubesi abufani ngokwezifunda, iphakeme kakhulu (okungukuthi inkinga inkulu kakhulu) e-Afrika eMaphakathi futhi iphansi kakhulu (okungukuthi, ayiyimbi kakhulu) eNingizimu ye-Afrika. Ukutholakala kwezinsiza kubonakala kukuhle kakhulu eRwanda, eChad naseBenin futhi kuphansi kakhulu emazweni ayisithupha ahlanganisa i-Angola, iBurkina Faso, iNiger, iSudan eseNingizimu, iSudan kanye ne-Uganda. Lokhu kuhlaziya kukhombise ukuthi izifunda zinezinkinga ezingafani. Ngiqhamuka nolwazi olusha mayelana nesimo sezinhlobo zamabhubesi futhi ngethula neziphakamiso ezintsha ezingaletha usintsho ekulawulweni kwamabhubesi ezifundeni ezahlukene. Njengoba amabhubesi ehlala esohlwini lokushabalala, futhi isibalo samabhubesi siqhubeka nokuncipha, ngiphakambisa ukuthi izindlela ezisetshenziswayo ezifundeni zibuyekezwe kubhekwe imininingo evezwe yilolu cwaningo nemiphumela yalo. Ukuqinisekisa ukuthi imininingo ekhiqiziwe ngesibalo samabhubesi inokwethembeka futhi iqinile, izindlela zokuhlola ezinokuvumelana zidinga ukuthuthukiswa futhi zisetshenziswe ezinhlotsheni ezahlukene zezilwane, ikakhulukazi ezindaweni lapho imininingo igqoza khona noma ingenele. Emhlabeni lapho esilahlekelwa khona izinhlobo zezilwane ngezinga elingakaze libonwe, ukulondolozwa nokunakekelwa kwezilwane kuyadingeka, futhi kuqondiswe imininingo yocwaningo, ukuze kuqinisekiswe ukuthi ibhubesi alubi yingxenye yohlobo lwezilwane ezigcina ngokuphela.
The impact of land-use change on arthropod diversity along an arid elevational gradient.
(2022) Mkhungo, S'phesihle.; Munyai, Thinandavha Caswell.; Foord, Stefan Hendrik.
Land-use change is a major threat to global biodiversity. The rapid growth of the human population has resulted in increased landscape modifications and habitat loss. The impact includes reduced species diversity, ecosystem instability, altered species interactions and altered food webs. Land-use has increased drastically in mountainous areas, mainly through agriculture and human settlements. Mountains support approximately one-third of the terrestrial diversity and host half of the global biodiversity hotspots. The high variation in habitat structure and microclimates, within short distances allows mountains to support high species diversity. This study aimed to investigate the impact of increasing land-use change, elevation, and season on selected arthropod diversity, and community composition along the Western Soutpansberg mountain range in Limpopo province of South Africa. The objectives of the study were to determine spider and ant diversity patterns along the mountain. Secondly, to determine the role of land-use, elevation, and season in structuring the diversity of both taxa. Lastly, to compare the composition of spider and ant assemblages across the various sites and identify indicator species for monitoring land-use change in the study area. A standardized pitfall trap survey was used to sample ants and spiders along an elevational transect that stretches across the southern and northern aspects of the mountain. The elevational transect (800 m a. s. l – 1700 m a. s. l) was made up of 18 sites, some of which have undergone human transformation mainly through agriculture and settlements. Sampling took place during the dry season (September 2019) and wet season (January 2020). Generalized linear mixed models with Poisson error distributions were used to determine the impact of land-use, elevation, season on spider and ant species richness and activity. Community composition was analyzed using NMDS (non-metric multidimensional scaling), PERMANOVA and ANOSIM analyses. Land-use had a positive effect on spider and ant diversity as the transformed sites had significantly higher species richness and activity for both taxa, particularly the agricultural sites and human settlement. However, species evenness was significantly lower in the transformed sites and higher in the natural sites. Species richness and activities for both taxa were highest at the low elevations. Spider diversity was higher in the dry season, but ants peaked in the wet season. Spider and ant assemblages were highly distinct between the land-use types and elevations. Ant assemblages remained similar between the seasons, while spider composition was slightly different across the two seasons. Spider and ant assemblages in the transformed sites were highly uneven which indicates a large disproportion in the number of individuals within the species found in transformed sites. It also indicates high species dominance, which is driven by the disturbance-tolerant species. One spider species, Copa flavoplumosa, was identified as an indicator species for the Eucalyptus plantations. All land-use types had an ant indicator species, which was either Monomorium damarense and/or Lepisiota sp.02 (spinosior gp.). High species dominance displayed by spider and ant assemblages in the modified habitats might have adverse effects on native and endemic communities. Because dominant and disturbance-tolerant species are likely to increase if more natural land is converted. This study was the first to investigate the impact of land-use changes at the Soutpansberg mountain range. The results indicate that landuse change had a positive effect on arthropod species richness and activity. However, species evenness was negatively affected. Although the land-use changes at Soutpansberg can increase the diversity of certain species, the potential to sustain the populations over the long term is unknown. Therefore, further assessments and monitoring of diversity in the region is recommended to understand the long-term impact of land-use and for informed decision making and strategy in conservation efforts.

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