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1.
We determined the contribution of ligneous species to the diet of cattle, sheep and goats across three agro-ecological zones of Burkina Faso, and assessed their ethno-veterinary uses by livestock keepers. Regular observation and GPS-tracking of one cattle, one sheep and one goat herd each in three villages served the investigation of browsing activities on pasture. Livestock keepers (25 per village) were interviewed on the use of ligneous plants by livestock and for disease treatment, and on changes in use over the past two decades.Across the three zones 75 species were of importance. Cattle preferred Afzelia africana, Pterocarpus erinaceus and Piliostigma sp., while small ruminants primarily fed on Balanites aegyptiaca, Ziziphus mauritiana and Acacia sp. Contribution of browsing to daily eating time was highest for goats across seasons and zones; for sheep and cattle browsing was important during the hot dry season with no differences between zones. Livestock keepers reported increasing browse use by their animals, while browse species use for traditional animal health care has decreased. The combination of anthropogenic pressures and climate change affect survival and regeneration of the most preferred trees and shrubs, and threaten livestock keepers' current management practices; this needs to be counteracted adequately.  相似文献   

2.
Michael Campbell 《Area》2009,41(2):139-148
Animal behaviour is vital for livestock choices, but is less researched in West Africa than economic considerations. An animal geography framework is applied to the socio-economic context of livestock behaviour in coastal Ghana, assessing the shared 'actant' behaviour of people and animals, and the contribution of such a study to animal geography and agricultural knowledge. Data were gathered on cattle, sheep and goat behaviour and the impact of these on human livelihoods, perceptions and the socio-environmental context. Animal behaviour was more important in the choice of livestock species, but economic considerations were more important in the decision to acquire animals. Goats had more incidents with people in village centres than sheep and cattle. Cattle had more incidents in farmland and grassland than goats and sheep. Women and young people were more affected by livestock behaviour. These findings increase the understanding of livestock zoogeography and livelihood decisionmaking, and contribute to animal geography by documenting the relevance of individualised gender- and age-based human behaviour, as well as intra- and inter-species animal behaviour to a shared actancy perspective, and a more dynamic zoogeography.  相似文献   

3.
In order to assess the effect of controlled seasonal breeding on survival performance of pastoral goat flocks, a systematic breeding programme was initiated in a herd of small East African goats over a period of 4 years in Isiolo District, northern Kenya. This papers presents an analysis of survival rates observed in six different mating seasons. The statistical analysis is based on modelling hazard functions parametrically over time using logistic regression and polynomial spline functions. With respect to kid survival, litter size and parity of dam failed to reach statistical significance after adjustment was made for the effects of birth weight and milk yield until weaning. Highly significant interactions were found between time factors and the effect of mating season, indicating non-proportionality of death risks across mating seasons. Confining mating to the period between June and November is likely to confer a distinctive advantage in terms of young livestock survival. In contrast, joining does during the short dry season leads to kid mortality rates of about 50%, and should therefore be avoided. Doe survival was evaluated in terms of mating season, production cycle, parity, and reproductive status. The ranking of mating season groups with respect to doe survival was similar to that observed in kids, although the differences were much smaller and non-significant. The lowest annual mortality rate was observed when breeding females were mated during the long dry season. It is concluded that confining breeding to the long dry season can be an effective management intervention to reduce mortality rates in pastoral goat flocks.  相似文献   

4.
The aim of this study was to determine the effect of drought on grazing patterns of livestock in a communal rangeland in Namaqualand. Water points were the foci of almost all grazing routes even after the drought, and the areas away from the water points were less heavily utilized. The mountains could be regarded as key resource areas for livestock since the grazing intensity was higher in the elevated areas of the rangeland than on the surrounding low lying areas during and immediately after drought. Spatial patterns of resource use by livestock on the commons did not differ during the drought and post-drought period. The lengths of the daily grazing routes were similar for both periods. This may be a consequence of the weakness of animals during the drought when forage was scarce which prevented them from walking further. The size of home ranges of the herds did not change during the two monitoring periods. We attribute this to social reasons because herders try to avoid the mixing of herds. In the commons of Namaqualand, herders are also spatially constrained and this restricts their options to adapt to drought, and hence many animals died.  相似文献   

5.
Previous studies conducted in the semiarid thornscrub of the Biosphere Reserve of Tehuacán-Cuicatlán have reported a high consumption of cactus and legume fruits by domestic goats. To test the hypothesis that goats may effectively disperse seed, we collected domestic goat feces from different microhabitats (bare ground, under shrub or under tree). The area occupied by each microhabitat was measured in the field. We then quantified the presence of viable seeds in goat feces and their deposition in microhabitats suitable for seedling establishment. We collected 209 seeds and using a seed reference collection, we identified these as belonging to three endemic cactus species, two legumes and several unidentified species. A high proportion of the cactus seeds germinated. Although most of the feces were found in open areas, more than 30% were recorded beneath the canopies of perennial plants, a suitable microhabitat for seedling establishment and survival. Contrary to the general assumption that goats cause only degradation of vegetation, these findings show that goats can effectively disperse viable seeds of diverse species. Studies that evaluate the ecological role of goats as important elements of biotic interactions are needed in order to generate an adequate management program for livestock.  相似文献   

6.
Monitoring cattle inflows and outflows over time is a good indicator of herd productivity. In this study, ninety households were monitored for a year to determine the effect of season, rangeland type and herd size on births, purchases, sales, deaths, off-take, cattle production potential (CPP) and cattle production efficiency (CPE) in the sweet and sour rangelands of South Africa. Most births were recorded in large herds in the sour rangelands during the hot-wet season (P < 0.05). Farmers with large herd sizes purchased significantly more cattle compared to those with small herd sizes. Cattle sales were significantly high in the large herds in the cool-dry season. Mortality was significantly high in the hot-wet season in the sour rangeland and was mainly caused by gall-sickness (24%) and redwater (20%). The highest mortalities were observed in cows (45%). Households owning small herds in the sweet rangeland had the lowest CPP in the cool-dry season (P < 0.05). The CPE was significantly high in the households owning large herds in the sweet rangeland. It was concluded that, although the CPP was low in the sweet rangeland, households in these areas had higher CPE compared to those in the sour rangelands.  相似文献   

7.
This article reviews and analyzes the available information on range and livestock production in the Monte Desert. Cow–calf operations, goats for meat, and sheep for wool are the dominant production systems under continuous grazing. Rest-rotational grazing systems improved the efficiency of the current cow–calf production. Forage resources are primarily composed of perennial grasses and woody species. Rain-use efficiency for the total vegetation ranged from 3.9 to 4.8 kg DM ha?1 year?1 mm?1. Carrying capacity showed a broad range: 18.7, 4.5–64.5, and 21.6–89.3 ha AU?1 in the north, central, and south portions of the Monte, respectively. Mean crude protein (CP) content of grasses varied from 8.4 to 10.3 (wet season) and 7.1–3.7% DM (dry season) in the central west and Patagonia, respectively. Grasses predominated in the cattle diet, while the sheep diet was highly diverse because they ate most of the available plant species, and there was no unanimity as to the fact that goats are strictly browsers. Livestock diseases have lower prevalence indices than those recorded in other areas of the country. The high variability in carrying capacity values could be attributed to differences in rangeland condition and to the different methods used for its estimation. The CP levels in forage could meet cattle requirements provided that a proper-stocking rate were used. The most promising species for land rehabilitation are Opuntia, Atriplex spp., Eragrostis curvula and Cenchrus ciliaris. Priorities for future research should include topics such as assessment of the carrying capacity for most of the areas and nutrient content of the components of livestock diet, the livestock intake values, the economic feasibility of the use of complementary feeds and the development of seeding technology for valuable forage resources as Trichloris crinita, among others.  相似文献   

8.
Pastoral production around artificial watering points in semi-arid environments affects the density and composition of plant communities. In the Kalahari desert of southwestern Africa, bush encroachment is often regarded as the major form of land degradation resulting from pastoral production around watering points. We investigated the OvaHerero pastoralists’ perceptions of the extent of vegetation change since the establishment of artificial watering points in the northern Kalahari desert of Namibia, and related this to ecological data on vegetation change. We determined the utility of woody vegetation to pastoralists’ livelihoods in terms of provision of construction material, fuel wood and browse. We quantified local knowledge of cattle browse consumption and correlated this with field data. We also assessed the purposes for which major livestock types were used. Our results showed that: (1) pastoral knowledge of bush encroachment and browse consumption was consistent with concurrently collected field data, (2) the current level of bush encroachment was perceived to be beneficial for pastoral production, and (3) cattle played an important role in the production of milk and milk by-products for domestic use, and served as a source of cash income, while sheep and goats were primarily kept for meat consumption. This result contrasts with historical studies that mainly portray cattle as a symbol of social status among OvaHerero pastoralists.  相似文献   

9.
Extensive herding is an important activity in northern Cameroon, in terms of both the local social economy and local land management. However, this activity is strongly linked to the availability and accessibility of fodder resources. Due to territorial processes, such as land clearance and wood harvesting, this resource is receding and pasturelands are becoming fragmented. Herders are facing new challenges to secure their livelihoods, and, in this context, fodder trees are emerging as a key resource, allowing herds to subsist up to the end of the dry season. Increasingly, trees are playing a significant part in the herders' strategies to feed their herds in time and space and to 'root' their activities to particular lands. This trend requires an analysis of the importance of fodder trees in the definition of territorial strategies operated by herders in northern Cameroon, in the context of various herding systems (nomadic herding, agro herding using transhumance, and settled agro herding). A discussion of herding strategies needed to address the decreasing access to fodder resources highlights the problems of current extensive herding systems and leads to proposed alternatives.  相似文献   

10.
Wild mammalian herbivores and cattle are fundamental drivers of African savanna ecosystems and have strong impacts on woody vegetation. However, few experimental studies have investigated the separate and combined influences of different large herbivores on spatial vegetation patterning. In East Africa, temporary cattle corrals (bomas) develop after abandonment into productive, treeless ‘glades’ that attract both domestic and wild herbivores. Edges of glades exhibit unusually high densities of large trees. We used a long-term, broad-scale manipulative experiment to test whether megaherbivores (elephants and giraffes), wild meso-herbivores (15–1000 kg), or cattle caused shifts in woody plant abundances in glade edges. We also examined cascading effects of megaherbivore and cattle exclusion on symbiotic Acacia ants and wild meso-herbivores in glade edges. Megaherbivore exclusion resulted in increased densities of tall trees, reproductive trees, and non-aggressive Acacia ant species in glade edges. Cattle presence reduced meso-herbivore use inside and away from glades, but not in glade edges. Our results suggest that megaherbivores and cattle can dampen the magnitude of spatial patterns associated with glades and glade edges. These findings provide insight into the development and maintenance of spatial heterogeneity in savannas, and emphasize that land use change and mammalian extinctions have complex, cascading ecological consequences.  相似文献   

11.
Faidherbia albida and Acacia erioloba (Mimosoideae) are important fodder trees for livestock and wildlife along the westward flowing ephemeral rivers of the Namib Desert. Together with other, mainly woody vegetation, F. albida and A. erioloba line these rivers and present a linear oasis in a resource poor environment. For centuries nomadic to semi-nomadic inhabitants seasonally utilised the resources of these ephemeral rivers to survive in the otherwise harsh desert environment. In the past decades, more permanent settlements were established along these rivers, with small stock subsistence farmers making a living from the available resources. Livestock (mainly goats) usually moves freely around, feeding on the available vegetation.This study investigated the influence of free moving animals on the regeneration and recruitment of F. albida and A. erioloba along the Kuiseb ephemeral river. It was found that a large numbers of recently emerged seedlings were removed soon after germination. In addition, tree densities of adult versus juvenile individuals differed in areas with large numbers of livestock. The overall height increase and health of juvenile plants were influenced negatively by browsing livestock. In general, browsing pressure differed spatially and was higher close to the main water channel.  相似文献   

12.
Mongolian herders are transhumant and therefore follow a specific land use pattern. To understand their movements through a case study, we mapped and superimposed their seasonal camps on a vegetation map and a digital elevation model. We also questioned them about the reasons justifying the locations of their camps, and how they use the surrounding land. It appears that vegetation quality may play a role only in summer, whereas topography is a key driver during 3 seasons. In winter, herders seek shelter against cold winds in rugged places exposed to the south, while in spring and summer, they seek flat places. In spring, to have a clear view of their newborns and in summer, to allow wind to reduce the insect discomfort. Moreover, most of the livestock species stay within a certain distance of the camps depending on the season, but which never exceeds 5.1 km. This leads to a land use pattern where livestock is restrained to specific areas according to the season. Interestingly, during the growing season, when plants are most sensitive to defoliation, most livestock is concentrated on 30.92% of the site surface. Such information is important for range scientists working on grazing impacts at large scales.  相似文献   

13.
Through surveys and participatory rural appraisal methods, the study documents the traditional cattle-husbandry systems in both the mixed crop–livestock system in the highlands and the pastoral system in the lowlands in Eritrea. Herding, grazing, breeding strategies, heat detection, milking letdown, food habits, marketing, housing and traditional veterinary practices are described in each system. The pastoral system is based on large, mobile, predominantly female herds that go for long-range grazing and cattle are mainly kept for milk and milk products. In the highland farming communities, cattle are sedentary, relatively fewer, predominantly male and are mainly kept to provide energy for agricultural purposes.  相似文献   

14.
Botanical composition of cattle seasonal diets (faecal sampling with microhistological analysis) was determined in a four-pasture, one-herd grazing system during a 3-year period. Diets were classified using cluster analysis. Three diet groups were identified: beginning of rainy season (spring), peak of rainy season (summer) and dry season (fall and winter). Contribution of grasses and woody species to these diet groups was significantly different (p< 0·001). Grasses were the most important component of cattle diets throughout the rainy season, while shrubs and trees were important in the dry season. The major shifts in diets occurred in response to changes in grass phenology.  相似文献   

15.
In South Africa, interventions in communal rangelands proposed by most agriculture-sector institutions are still dominated by the belief that communal herders have little technical skills and by the tenets of “the tragedy of the Commons”, assuming that individual livestock keepers are selfish, norm free, and aiming at maximising short-term offtake and that there is no consistent management of the commons. In this study we show that practices of a diversity of livestock keepers on the Leliefontein Commons of Namaqualand are at odds with this viewpoint: access to rangeland and its use are structured by collective norms and concerns regarding both the sharing of resources and their long-term sustainability. We also show that part of the management of the commons relies on grazing practices which involve tacit and formalised technical knowledge that can be described and modelled. Livestock keepers assess the heterogeneity of the grazing quality of the commons. They are aware of the toxicity and unpalatability of some plants, of the way this differs according to the amount ingested and the availability of other forage, and of the variations of these two factors over seasons of grazing. They classify grazing areas and decide on daily grazing routes according to a complex set of criteria. Carrying capacity of each area is not considered as a fixed parameter but rather as a variable dependant on rainfall. Seasonal movements between areas are designed accordingly. These findings offer a new perspective for research agendas on technical models and extension measures for communal rangeland management particularly in arid and semi-arid areas.  相似文献   

16.
Understanding pastoral mobility: the case of Senegalese Fulani   总被引:2,自引:0,他引:2  
Based on a case study from Sahelian Senegal, this paper analyses how various actors perceive the importance of pastoral mobility and presents issues of importance for understanding the use of mobility among Fulani of Ferlo. One knowledge system is a scientific one, the 'new rangeland paradigm'. According to this, pastoral mobility is a means to balance variability in dryland resources; hence, 'nature' is the point of departure. Another knowledge system is local pastoral knowledge. For the pastoralists, the well-being of their animals is the point of departure and mobility is used to ensure that the livestock are in good condition. The paper shows that it is important to distinguish between mobility of pastoralists and of their herd; even though the pastoralists of northern Senegal have become semi-sedentary, their herds are still quite mobile. The pastoralists are willing to move around within a small territory, which they consider their place, but are unwilling to employ large-scale mobility themselves. Mobility is not of importance for their ethnic identity and some use paid herders to care for their livestock. By looking at both knowledge systems, we achieve a better understanding of pastoral mobility and how this may change in the future.  相似文献   

17.
科尔沁沙地优势固沙灌木叶片凋落物分解的主场效应   总被引:2,自引:1,他引:1  
在气候变化和人类活动的影响下,科尔沁沙质草地中灌木植物种增加,导致沙质草地逐渐向灌木地转变。选取该地区优势固沙灌木差不嘎蒿(Artemisia halodendron)和小叶锦鸡儿叶(Caragana microphylla)凋落物及其混合凋落物开展交互移置培养试验,分析了培养过程中CO2释放和干物质损失量以及混合凋落物CO2释放量实测值与预测值的差异,辨析主场效应产生的原因及其驱动机制,以期为将主场效应纳入到凋落物分解模型提供理论基础。结果表明:与高质量的小叶锦鸡儿叶凋落物相比,质量较低的差不嘎蒿叶凋落物分解具有更强的主场效应;其次,引起叶凋落物分解的主场效应归因于土壤微生物的特化作用,而不是土壤动物的搬运或贮藏行为。此外,混合凋落物主场效应与其分解生境中长期输入的凋落物的质量相似性紧密相关,质量相似性越大,主场效应越强,这也是本研究中混合凋落物分解在差不嘎蒿灌丛土壤下具有较强主场效应的原因。  相似文献   

18.
The proliferation of woody plant species on savanna rangelands (i.e. bush encroachment) degrades rangeland quality, thereby threatening the biodiversity conservation effort as well as pastoral farming. Hyperspectral remote sensing offers possibilities for discriminating encroaching bush species in support of management of semi-arid savanna rangelands. As a preliminary step towards establishing a spectral library of common encroaching species on savanna rangelands, the effect of canopy leaf cover, background dry soil and grass on the spectral profiles of the common encroaching species Acacia karroo, Acacia mellifera, Acacia tortilis and Dichrostachys cinerea was analysed. A sample of healthy mature plants in prime, full leaf condition was utilised at an encroached rangeland in Mokopane, South Africa. The spectral signatures were collected in-situ, using a field spectrometer pointed above the sample specimen canopies. The canopy and canopy background variables tended to modify the reflectance of the encroaching bush species in the near infrared (800–1300 nm) in which they were spectrally most separable. Canopy background dry grass tended to increase near infrared reflectance, while dry soil tended to reduce the spectral contrast among the species. These effects were reduced by high leaf content. In a thicket canopy structure, the overall reflectance tended towards the spectral profile of the more dominant species.  相似文献   

19.
对福建省三明市格氏栲天然林及在其采伐迹地上营造的33年生格氏栲人工林和杉木人工林这3种林分的枯枝落叶层及粗木质残体物质化学组成进行研究.结果表明:在分解过程中3种林分枯叶和枯枝水溶性物质和纤维素含量不断下降,而枯枝中苯醇溶性物质和粗蛋白质含量有所上升.除半纤维素和纤维素外,3种林分粗木质残体水溶性物质、木质素和粗蛋白质含量均为L层〉F层,而苯醇溶性物质含量为L层〈F层.格氏栲天然林枯叶和枯枝水溶性物质、木质素、粗蛋白质、半纤维素和纤维素总贮量最高,而苯醇溶性物质总贮量以格氏栲人工林的最高.3种林分F层枯叶和枯枝有机物质的总贮量高于L层.与2种人工林相比,格氏栲天然林粗木质残体中各种有机物质贮量均最高.  相似文献   

20.
甘肃省摩天岭北坡木本植物叶性状变异及关联   总被引:1,自引:0,他引:1  
李宗杰  田青  宋玲玲 《中国沙漠》2018,38(1):149-156
调查了摩天岭北坡以常绿阔叶林带与落叶阔叶混交林为主的低海拔区(700~1 500m)和针阔叶混交林与亚高山针叶林为主的高海拔区(2 100~3 400m)的21个木本植物群落组成,测定了104种植物的比叶面积(SLA)、叶干物质含量(LDMC)、叶片全磷含量(TPC)、叶片全氮含量(TNC)、叶片全碳含量(TCC)以及叶片厚度(LT)等6个植物功能性状。采用相关性分析对6个植物功能性状的变异和关联进行分析。结果表明:(1)SLA、LT和TCC在高海拔区明显高于低海拔区,而LDMC和TNC表现出高海拔区低于低海拔区;(2)SLA均随海拔的升高表现出降低的趋势,而LDMC和LT都随海拔的升高呈现增加的趋势。低海拔区TCC和高海拔区TCC都随海拔的升高呈增加的趋势;低海拔区TNC和TPC随海拔的变化与高海拔区相反,TNC和TPC在低海拔区随着海拔的升高表现出增加的趋势,而在高海拔区随海拔的增加呈现降低的趋势。(3)在高、低海拔区,SLA与LDMC、LT和TCC均呈极显著的负相关关系(P<0.01),LDMC与LT和TCC呈极显著的正相关关系(P<0.01)。摩天岭北坡不同海拔区木本植物叶片功能性状与海拔的关系,反映了该区域木本植物的不同叶片功能性状对海拔决定的环境异质性的协同响应和适应。  相似文献   

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