{"title":"Genetic analysis of Panicum coloratum var. makarikariense caryopsis retention","authors":"María FM Lirusso, F. Pozzi, G. Pratta, S. Felitti","doi":"10.2989/10220119.2021.1990127","DOIUrl":"https://doi.org/10.2989/10220119.2021.1990127","url":null,"abstract":"Panicum coloratum is a species of C4 type grass native to South Africa. In Argentina, it is valued for its production of good quality forage in environments where resources are limiting, although it is infrequently cultivated in livestock systems. The purpose of this study was to estimate the narrow sense heritability (h 2) of the caryopses fall character using the Progeny-Parent Regression method and characterise molecular diversity using ISSR-type markers. The only significant value obtained was in week five, which gives an indication of the existence of additive genetic variance and also its stability. The ISSR markers allowed confirming the existence of genetic variability between cultivars and within individuals of the same cultivar through bands and unique alleles per genotype. The individuals of the Kapivera cultivar have been able to genetically differentiate themselves from the individuals of the Bambatsi cultivar by detecting loci and alleles that differentiate both cultivars. These markers proved to be effective for the distinction of the cultivars analysed and a wide variability has been observed in the species. The characterisation of the genetic diversity within the cultivars of P. coloratum var. makarikariense constitutes a fundamental step for its potential incorporation into breeding programs developed in the species.","PeriodicalId":50841,"journal":{"name":"African Journal of Range & Forage Science","volume":"72 1","pages":"173 - 180"},"PeriodicalIF":1.4,"publicationDate":"2021-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80123832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Natural Resource Management Reimagined: Using the Systems Ecology Paradigm","authors":"P. Scogings","doi":"10.2989/10220119.2021.2002410","DOIUrl":"https://doi.org/10.2989/10220119.2021.2002410","url":null,"abstract":"","PeriodicalId":50841,"journal":{"name":"African Journal of Range & Forage Science","volume":"9 1","pages":"298 - 299"},"PeriodicalIF":1.4,"publicationDate":"2021-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75310897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. L. Raubenheimer, Kimberley J. Simpson, Richard Carkeek, B. Ripley
{"title":"Could CO2-induced changes to C4 grass flammability aggravate savanna woody encroachment?","authors":"S. L. Raubenheimer, Kimberley J. Simpson, Richard Carkeek, B. Ripley","doi":"10.2989/10220119.2021.1986131","DOIUrl":"https://doi.org/10.2989/10220119.2021.1986131","url":null,"abstract":"Fire plays an important role in maintaining the savanna tree-grass balance by limiting the recruitment of heat-sensitive tree seedlings. However, fire behaviour may change under increasing CO2 concentrations, due to altered flammability of the grassy layer. Here, we determined the effect of predicted future CO2 concentrations, and how it interacts with water-availability, on grass flammability and traits influential to flammability, and uncovered the physiological mechanisms underpinning these responses. Using the widespread C4 savanna grass, Themeda triandra, as a model, we found that improved water-use efficiency under elevated CO2 (800 ppm) resulted in a larger (greater aboveground biomass), but wetter (higher moisture content) grass fuel load, that cured at a slower rate under drought conditions. These changes were associated with increased time to ignition, reduced flaming times and reduced predicted rate of spread. We modelled the effect of altered grass flammability on fire behaviour at a national level (South Africa), finding large-scale reductions in fire spread under elevated CO2, mitigating the converse effects of predicted increases in aridity, and marginal increases in fireline intensity. CO2-induced reductions in fire frequency, spread or intensity could have serious implications for savanna vegetation dynamics, possibly exacerbating the woody encroachment already seen in these ecosystems across the world.","PeriodicalId":50841,"journal":{"name":"African Journal of Range & Forage Science","volume":"47 1","pages":"82 - 95"},"PeriodicalIF":1.4,"publicationDate":"2021-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90591231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
I. Smit, M. Joubert, Kyle Smith, Nicola J. van Wilgen, T. Strydom, J. Baard, M. Herbst
{"title":"Fire as friend or foe: the role of scientists in balancing media coverage of fires in National Parks","authors":"I. Smit, M. Joubert, Kyle Smith, Nicola J. van Wilgen, T. Strydom, J. Baard, M. Herbst","doi":"10.2989/10220119.2021.1991473","DOIUrl":"https://doi.org/10.2989/10220119.2021.1991473","url":null,"abstract":"Fire can destroy infrastructure and livelihoods, and claim lives. Yet, fire is inevitable and plays several vital ecological roles that have shaped ecosystems over millennia. Planned fires also serve human needs. Critical media content analysis of 390 media reports (print, online and broadcast) on fires in South African National Parks over a three-year period were used to investigate the portrayal of fire by the mass media. We found a strong emphasis on reactive fire suppression along with a predominantly negative sentiment towards fire (93.9% of total media reach) focussing primarily on losses, destruction and the threat of fires to infrastructure, human health or lives and vegetation. In the few cases where scientists were involved (2.3% of total reach), the narrative, sentiment and images provided a more nuanced perspective of fire as having both detrimental and beneficial consequences (63.6%), imparting key fire ecology concepts to understand fire behaviour better and highlighting the importance of proactive fire-risk reduction measures. Given the influence of the mass media on the views and opinions of the public and policymakers, and its socio-political and management consequences, we conclude that scientists and journalists should do more to engage with one another. We provide pathways and tips to scientists on how to increase their media footprint to promote a more balanced media portrayal of fire. GRAPHICAL ABSTRACT","PeriodicalId":50841,"journal":{"name":"African Journal of Range & Forage Science","volume":"10 1","pages":"136 - 147"},"PeriodicalIF":1.4,"publicationDate":"2021-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85347144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A laissez-faire management approach in a grassland landscape results in a fine-scale, spatio-temporally heterogeneous fire pattern","authors":"M. Stalmans, E. Witkowski, K. Balkwill","doi":"10.2989/10220119.2021.1987321","DOIUrl":"https://doi.org/10.2989/10220119.2021.1987321","url":null,"abstract":"What are the spatio-temporal characteristics of a fire pattern that is allowed to develop over time across a species- rich, predominantly grassy landscape? More than 1 300 fires were documented over 13 years in the 48 000 ha Songimvelo Game Reserve in the Barberton Mountainland, South Africa. Most fires were set by pastoralists and were uncontrolled. Lightning fires and prescribed burns made up <2% and <8% respectively of the total area burnt. Median and mean burn areas in the 31 700 ha game-fenced section were 35 and 187 ha respectively with a fire return period of 2.9 years. In the less-grazed 14 000 ha section that receives a higher annual rainfall, median and mean fire sizes were 124 and 501 ha and the return period was 1.5 years. These fire return periods are in line with generally accepted management prescriptions for grasslands. The annual number of fires, individual patches and different fire histories occurring in a moving window across the landscape were consistently higher, compared with those resulting from a small-scale or large-scale fixed fire regime. This laissez-faire approach thus resulted in a fine-scale, dynamic fire pattern with high landscape indices that could be conducive to maintaining biodiversity.","PeriodicalId":50841,"journal":{"name":"African Journal of Range & Forage Science","volume":"52 1","pages":"175 - 188"},"PeriodicalIF":1.4,"publicationDate":"2021-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90985522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Fire and herbivory shape belowground bud banks in a semi-arid African savanna","authors":"A. Bombo, F. Siebert, A. Fidelis","doi":"10.2989/10220119.2021.1982004","DOIUrl":"https://doi.org/10.2989/10220119.2021.1982004","url":null,"abstract":"Fire and herbivory are major drivers in tropical savanna ecosystems and they selected a flora composed of species able to cope with recurrent aboveground biomass removal. Renewal of the herbaceous stratum is made possible by resprouting, mostly through a belowground bud bank. Evaluating the impacts of disturbances on the bud bank can assist in predicting post-disturbance responses and system resilience. In a semi-arid savanna, we aimed to verify whether lower fire frequency, fire and herbivory exclusion could affect belowground bud bank and organs diversity and consequently, the resprouting potential. Lower fire frequency or suppression and absence of herbivory were expected to reduce the bud bank density, which was confirmed by our results. If the fire is suppressed or fire frequency is reduced, the total, graminoid and the shrub bud bank decreased, whereas herbivory exclusion resulted in total and a forb bud bank of lower densities. Belowground buds were identified in non-woody and woody rhizomes, stolons, root crowns, and bulbs or corms. Despite having bud banks of lower density, disturbance exclusion promoted belowground biomass accumulation. Our results indicated the importance of maintaining the endogenous disturbances to the preservation of the belowground community and regeneration strategy, guaranteeing resilience in semi-arid savanna communities.","PeriodicalId":50841,"journal":{"name":"African Journal of Range & Forage Science","volume":"18 1","pages":"16 - 26"},"PeriodicalIF":1.4,"publicationDate":"2021-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75350936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Nutritional quality of Calobota sericea fodders. A preliminary assessment","authors":"F. Müller, Clement F Cupido, M. I. Samuels","doi":"10.2989/10220119.2021.1989722","DOIUrl":"https://doi.org/10.2989/10220119.2021.1989722","url":null,"abstract":"This study aimed to provide preliminary information regarding the nutritional quality of Calobota sericea, a preferred perennial legume forage species from the water-limited rangelands of South Africa. Calobota sericea plant samples were collected from the Namaqualand rangelands in the wet and dry season and analysed for secondary compounds, fibre, protein and mineral nutrient content. The results from the fibre analyses were used to determine the digestibility and energy content of fodders. Preliminary results indicate that C. sericea fodders are of better nutritional quality in the wet season and that protein content, digestibility and energy content is sufficient for maintenance of lambs and dry ewes. The energy content, however, was not sufficient for maintenance of pregnant and lactating ewes. Furthermore, certain mineral nutrients (Na, P and K) were not found in sufficient concentrations in this species, and it was thus suggested that further investigation is needed into whether fertilisation could potentially improve the protein, digestibility and mineral nutrient content of C. sericea fodders.","PeriodicalId":50841,"journal":{"name":"African Journal of Range & Forage Science","volume":"71 1","pages":"S94 - S97"},"PeriodicalIF":1.4,"publicationDate":"2021-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86381543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Takudzwa Charambira, S. M. Kagande, I. Chakoma, Gwinyai Chibaira, P. Mugabe
{"title":"Goat feeds and feeding practises in a semi-arid smallholder farming system in Zimbabwe","authors":"Takudzwa Charambira, S. M. Kagande, I. Chakoma, Gwinyai Chibaira, P. Mugabe","doi":"10.2989/10220119.2021.1981444","DOIUrl":"https://doi.org/10.2989/10220119.2021.1981444","url":null,"abstract":"This study was conducted to identify the available goat feed resources for smallholder farmers in the semi-arid region of Zimbabwe. An ecological rangeland assessment was combined with participatory research methods to determine the diversity of feed resources in two wards of the Beitbridge District, namely Chamunangana and Joko. One hundred and twenty households were surveyed. All farmers depended on rangeland as the main feed resource. Some 87% of the respondents indicated that rangeland was not adequate, yet only 54% practiced supplementation. Participants predominantly used crop residues (40%), browse tree foliage (28%) and commercial feeds (22%) as supplements. Of the 46% who did not apply supplements, 53% attributed this to unavailability of feeding material and 29% were not aware of the importance, whereas the rest thought it unnecessary. Farmers in Chamunangana and those who milked their goats were more likely to supplement feed (p < 0.05). Respondents who supplemented had received training in goat husbandry (p < 0.05). The Shannon–Wiener diversity index (H′) was higher in Chamunangana (1.29), compared with Joko (1.19). There was no difference in biomass production between the study sites (p > 0.05). Improved goat nutrition could be achieved through farmer trainings in goat husbandry and incorporating available feeds into balanced rations.","PeriodicalId":50841,"journal":{"name":"African Journal of Range & Forage Science","volume":"5 1","pages":"S90 - S93"},"PeriodicalIF":1.4,"publicationDate":"2021-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82874415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Louhaichi, Rajabov Toshpulot, H. Moyo, A. Belgacem
{"title":"Effect of slope aspect on vegetation characteristics in mountain rangelands of Tajikistan: considerations for future ecological management and restoration","authors":"M. Louhaichi, Rajabov Toshpulot, H. Moyo, A. Belgacem","doi":"10.2989/10220119.2021.1951840","DOIUrl":"https://doi.org/10.2989/10220119.2021.1951840","url":null,"abstract":"Tajikistan’s rangelands are mostly mountainous and consist of summer and winter pastures. Vegetation structure and composition in these diverse landscapes are generally influenced by environmental factors. The objective of this study was to assess the effects of aspect on vegetation characteristics of two mountainous pastures (summer and winter) over two seasons (autumn and spring) in Tajikistan. A three-way ANOVA was conducted using GLM procedures to test the main effects and interactions of these factors on vegetation attributes. The biomass production (kg DM ha−1) was significantly greater on the north-facing aspects for both summer and winter pastures in spring (483.4, 326.1) and autumn (57.2, 143.9), compared with south-facing aspects (57.2, 143.9 in spring and 18.5, 48.2 in autumn, respectively). Plant cover and plant density were also greater on north than south-facing slopes for summer and winter pastures in spring and autumn. Aspect significantly affected species diversity, botanic composition, and plant life forms of both pastures mainly for grasses and geophytes. There were greater vegetation responses on north than south-facing slopes, implying that aspect is important when designing mountain rangeland restoration. Given this complexity, land managers should thoroughly assess the conditions of the target site before defining restoration objectives and interventions.","PeriodicalId":50841,"journal":{"name":"African Journal of Range & Forage Science","volume":"9 1","pages":"320 - 328"},"PeriodicalIF":1.4,"publicationDate":"2021-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75172963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}