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1.
Rangeland-based animal husbandry has been frequently exposed to the vagaries of weather. While the current rates of climate variability are unprecedented in arid and semiarid regions, climate change is expected to put further pressure on rangelands with medium- and poor-quality forages and increase the vulnerability of households who mainly depend on livestock production. Therefore, it is imperative to ensure that livestock producers increase their resilience to climate variability or change. However, few field-based studies have focused on simultaneous investigation of both vulnerability and adaptation of livestock keepers to climate-related risks. To fill this gap, a field-based research study was conducted in southwest Iran. A survey of 274 herder families, selected using a cluster sampling technique, revealed low, medium and high levels of vulnerability, which were principally distinguished by various degrees of exposure, sensitivity, and adaptive capacity. Further, this study identified the main adaptation strategies employed by the herders of this region (i.e., purchasing fodder; rotational grazing; raising a mixed-herd, on-farm occupation; and postharvest grazing). Results indicated that most herder families applied traditional adaptation strategies in response to climate variability. Findings revealed that herders had to reduce their livestock due to low adaptability. Loan term, purchasing insurance, level of exposure, income, experience, response efficacy, and knowledge were the major determinants of the herders’ adaptation decisions. To increase the resilience of livestock producers against climate change, restructuring traditional livestock production systems, producing participatory knowledge and information for sustainable management of rangelands, and designing or redesigning effective adaptation strategies are required.  相似文献   

2.
Recent climatic trends and climate model projections indicate that climate change will modify rangeland ecosystem functions and the services and livelihoods that they provision. Recent history has demonstrated that climatic variability has a strong influence on both ecological and social components of rangeland systems and that these systems possess substantial capacity to adapt to climatic variability. Specific objectives of this synthesis are to: 1) evaluate options to mitigate greenhouse gas emissions and future climate change; 2) survey actions that individuals, enterprises, and social organizations can use to adapt to climate change; and 3) assess options for system transformation when adaptation is no longer sufficient to contend with climate change. Mitigation for carbon sequestration does not appear economically viable, given the small and highly variable carbon dioxide fluxes of rangeland ecosystems and the high transaction costs that would be incurred. In contrast, adaptation strategies are numerous and provide a means to manage risks associated with climate change. Adaptation strategies are diverse, including altered risk perception by individuals, greater flexibility of production enterprises, and modifications to social organizations that emphasize climatic variability, rather than consistency. Many adaptations represent “no regrets” actions because their implementation can be justified without emphasis on pending climate change. Adaptations specific to livestock production systems can include flexible herd management, alternative livestock breeds or species, innovative pest management, modified enterprise structures, and geographic relocation. Social-ecological systems in which adaptation is insufficient to counter the adverse consequences of climate change might undergo transformative change to produce alternative ecosystem services, production enterprises, and livelihoods. The rangeland profession is in a pivotal position to provide leadership on this global challenge because it represents the intersection of management and scientific knowledge, includes diverse stakeholders who derive their livelihoods from rangelands, and interacts with organizations responsible for rangeland stewardship.  相似文献   

3.
There is rapidly growing national interest in grazing lands’ soil health, which has been motivated by the current soil health renaissance in cropland agriculture. In contrast to intensively managed croplands, soil health for grazing lands, especially rangelands, is tempered by limited scientific evidence clearly illustrating positive feedbacks between soil health and grazing land resilience, or sustainability. Opportunities exist for improving soil health on grazing lands with intensively managed plant communities (e.g., pasture systems) and formerly cultivated or degraded lands. Therefore, the goal of this paper is to provide direction and recommendations for incorporating soil health into grazing management considerations on grazing lands. We argue that the current soil health renaissance should not focus on improvement of soil health on grazing lands where potential is limited but rather forward science-based management for improving grazing lands’ resilience to environmental change via 1) refocusing grazing management on fundamental ecological processes (water and nutrient cycling and energy flow) rather than maximum short-term profit or livestock production; 2) emphasizing goal-based management with adaptive decision making informed by specific objectives incorporating maintenance of soil health at a minimum and directly relevant monitoring attributes; 3) advancing holistic and integrated approaches for soil health that highlight social-ecological-economic interdependencies of these systems, with particular emphasis on human dimensions; 4) building cross-institutional partnerships on grazing lands’ soil health to enhance technical capacities of students, land managers, and natural resource professionals; and 5) creating a cross-region, living laboratory network of case studies involving producers using soil health as part of their grazing land management. Collectively, these efforts could foster transformational changes by strengthening the link between natural resources stewardship and sustainable grazing lands management through management-science partnerships in a social-ecological systems framework.  相似文献   

4.
Rangelands are areas used primarily for grazing by domestic livestock; however, because they support native vegetation and fauna, their potential role in conservation should not be overlooked. Typically, “off-reserve” conservation in agricultural landscapes assumes a trade-off between maintaining the ecological processes that support biodiversity and successful food production and profitability. To evaluate this potential biodiversity trade-off in rangelands, we need to understand the effect of different livestock grazing strategies on biodiversity, in relation to their performance in terms of profitability and land condition. We monitored reptile community responses to four cattle-grazing strategies (heavy, moderate, and variable stocking rates and a rotational wet season spelling treatment) in a replicated, long-term grazing trial in north Queensland, Australia. Simultaneously, measures of profitability and land condition were collected for the different grazing strategies. Overall, reptile abundance was not negatively impacted by the more sustainably managed treatments (moderate, variable, and rotational) compared with heavy stocking, although the effect of grazing treatment alone was not significant. Profitability and land condition were also higher in these treatments compared with the heavy stocking rate treatment. As drought conditions worsened over the 3 yr, the negative impact of the heavy stocking treatment on both profitability and biodiversity became more pronounced. Heavy stocking negatively impacted reptiles and was also the least profitable grazing strategy over the long term, resulting in the worst land condition. This suggests that in this tropical savanna rangeland there was no trade-off between economic performance and reptile abundance and diversity. Grazing regimes with a moderate stocking rate or flexible management strategies were better able to buffer the effects of climate variability. The consequence was a more resilient reptile community and better economic outcomes in dry years.  相似文献   

5.
The past decade has seen a rapid rise in beaver-related stream restoration (BRR) using beavers and beaver dams (real or artificial) as a tool. Potential benefits of this low-cost, nature-based restoration approach include restoring aquatic and riparian habitat and recovering of threatened species dependent on it, improving water availability and stream flow regulation, reducing erosion and stream incision, and supporting climate change adaptation. Although the ecological restoration literature acknowledges the importance of addressing the human dimensions of restoration, there is a gap regarding the human dimensions of BRR. To help fill this gap we examined six projects involving riparian revegetation or artificial beaver dams to identify central elements of a supportive social environment for BRR on western rangelands. Our research questions examined how beavers, beaver dams, and BRR affect ranching operations and how ranchers view them; the policy context for BRR; and how BRR practitioners, regulatory agencies, ranchers, and partners work together for successful BRR. We synthesized our findings across cases and identified six social factors important for BRR: 1) ranchers who perceive the benefits of beavers, beaver dams, and BRR to outweigh the drawbacks; 2) education and assistance to help landowners adopt nonlethal mitigation techniques for nuisance beavers; 3) grazing practices compatible with BRR; 4) low harvest pressure on beavers; 5) a regulatory environment that enables experimentation, flexibility, and adaptive management; and 6) proponents, ranchers, and partners willing to take risks, innovate, be flexible, and stay committed.  相似文献   

6.
Rangeland ecosystems cover approximately one-third of the land area in the United States and half of the land area of California. This large land area, coupled with the propensity of grasses to allocate a considerable proportion of their photosynthate belowground, leads to high soil carbon (C) sequestration potential. Annual grasslands typical of the Mediterranean climates of the western United States differ in their life history strategies from the well-studied perennial grasslands of other regions and thus may also differ in their soil C pools and fluxes. In this study we use the literature to explore patterns in soil C storage in annual grass-dominated rangelands in California. We show that soil C is highly predictable with depth. Cumulative soil C content increased to 2–3-m depth in rangelands with a woody component and to at least 1-m depth in open rangelands. Soil C within a given depth varied widely, with C content in the top 1-m depth spanning almost 200 Mg C · ha?1 across sites. Soil C pools were not correlated with temperature or precipitation at a regional scale. The presence of woody plants increased C by an average of 40 Mg · ha?1 in the top meter of soil. Grazed annual grasslands had similar soil C content as ungrazed grassland at all depths examined, although few details on grazing management were available. Soil C pools were weakly positively correlated with clay content and peaked at intermediated levels of aboveground net primary production. Our results suggest that annual grasslands have similar soil C storage capacity as temperate perennial grasslands and offer an important resource for mitigation of greenhouse gas emissions and climate change.  相似文献   

7.
In this article we test the notion that adaptation to climate change in grazed rangelands requires little more effort than current approaches to risk management because the inherent climate variability that characterizes rangelands provides a management environment that is preadapted to climate change. We also examine the alternative hypothesis that rangeland ecosystems and the people they support are highly vulnerable to climate change. Past climate is likely to become an increasingly poor predictor of the future, so there is a risk in relying on adaptation approaches developed solely in response to existing variability. We find incremental, autonomous adaptation will be sufficient to deal with most of the challenges provided by the gradual expression of climate change in the next decade or two. However, projections of greater climate change in the future means that the responses required are qualitatively as well as quantitatively different and are beyond the existing suite of adaptation strategies and coping range. The proactive adaptation responses required go well beyond incremental on-farm or local actions. New policies will be needed to deal with transformational changes associated with land tenure issues and challenges of some displacement and migration of people in vulnerable parts of rangelands. Even where appropriate adaptation actions can be framed, issues of when to act and how much to act in a proactive way remain a challenge for research, management, and policy. Whether incremental or transformational involving system changes, a diversity of adaptation options will be required in different rangeland regions to enhance social and ecological resilience.  相似文献   

8.
草田是人类和动物等的食物资源和栖息环境,具有涵养水源、保护生态多样性、减缓气候变化和维持地区可持续发展等作用。目前气候变化、人口增加、水资源和能源资源短缺等对国际草田资源带来严重威胁。为了提高土地生产力,养活不断增加的人口,近几十年大部分国家将半自然状态草地转变农耕地,农耕地管理引起动生物多样性降低和植物群落栖息环境碎片化、退化和消失等。如果国际草田实施粮草轮作、粮草畜协同发展、科学放牧和饲养管理、粮草同等种植优惠政策等,不仅可以提高土地生产力,而且有利于保护生态环境和人类生存可持续发展。  相似文献   

9.
韩枫  张志涛  张鑫  王建浩  王浩 《草业学报》2022,31(9):220-232
通过文献梳理的方式阐明了美国公共牧草地法治化管理进程,并以立法节点为依据,划分为应对草地退化、确立多用途利用与联邦所有制、调整放牧费制度、修正立法及完善政策4个阶段,详述了各阶段的矛盾冲突、治理目标及政策手段,并总结特征。研究发现,草地经历严重退化后,联邦政府积极治理,以立法确立了公有制下的多用途使用原则。法治进程中,分类管理、放牧费制度、公有制、土地资源调查、市场化探索贯穿始终,法治管理手段不断完善,形成了稳定的治理格局。从现代产权制度看,草原资源公有制对资本主义私有制国家亦是一种有效的产权管理探索形式,在私有草原之外,形成了相对完善的法理体系和有效的法治治理基础。尽管中美两国政治经济体制、产权结构不同,但美国公共牧草地管理历程依然为中国提供了较为丰富的经验借鉴,研究认为,中国应在草原国有的公有制原则下,强化草原生态环境保护的法治化;清查草地资源,实施产责明晰的分类分级管理,同时开展生态与民生效益监测;将草原生态补偿及草原重点生态工程纳入常规化法治管理;充分发挥市场作用,实现生态产品多元化供给。  相似文献   

10.
Adapting what we currently know about ecosystems to a future where rangelands are changing is a new frontier in rangeland management. Current tools for knowledge discovery and application are limited because they cannot adequately judge ecological relevance of knowledge to specific situations. We propose development of integrated knowledge systems (KSs)—collections of resources (e.g., data, analytical tools, literature) drawn from disparate domains and organized around topics by process-based conceptual models. An integrated KS would define relevance by ecological attributes (e.g., soils, climate, vegetation) and location as a flexible mechanism for organizing, finding, and applying knowledge to rangeland management. A KS provides knowledge sources within a decision-making framework that defines what knowledge is needed and how it will be used to make decisions. Knowledge from a KS can identify appropriate spatial and temporal scales to address specific resource questions or objectives. Several factors currently limit KS development and implementation. These include limited interoperability of disparate information and knowledge systems; lack of consistent geographic referencing of knowledge; incomplete and inconsistent documentation of the origin, history and meaning of data and information; underexploited application of remote sensing products; limited ability to extrapolate and share local knowledge and unstructured information; and lack of training and education of professionals that can link ecological and technical fields of study. The proposed KS concept and recommendations present an opportunity to take advantage of emerging technologies and the collective knowledge of rangeland professionals to address changing ecosystems and evolving threats. If we keep on with a “business as usual” approach to finding and using information, we will struggle to meet our responsibilities as rangeland professionals.  相似文献   

11.
12.
Domestic livestock have the potential to function as ecosystem engineers in semiarid rangelands, but prevailing management practices largely emphasize livestock production and uniform use of vegetation. As a result, variation in vegetation structure might not occur at appropriate spatial and temporal scales to achieve some contemporary conservation objectives. Here, we introduce the utility of livestock as ecosystem engineers and address potential benefits and consequences associated with heterogeneity-based management practices for conservation grazing in the semiarid rangelands of the western North American Great Plains. To illustrate the potential value of this approach, we provide specific examples where engineering effects of livestock could alter vegetation heterogeneity at within-pasture (< 100 ha) and among-pasture (~100 ha to thousands of hectares) scales to improve habitat for declining native grassland birds. Experimental evaluations of the efficacy of livestock to achieve desired modifications to vegetation structure are needed, along with the economic aspects associated with implementing heterogeneity-based management practices. Using livestock as ecosystem engineers to alter vegetation structure for grassland bird habitat is feasible in terms of application by land managers within the context of current livestock operations, and provides land managers important tools to achieve desired contemporary objectives and outcomes in semiarid rangelands of the western North American Great Plains.  相似文献   

13.
Experiments investigating grazing systems have often excluded ranch-scale decision making, which has limited our understanding of the processes and consequences of adaptive management. We conducted interviews and vegetation monitoring on 17 ranches in eastern Colorado and eastern Wyoming to investigate rancher decision-making processes and the associated ecological consequences. Management variables investigated were grazing strategy, grazing intensity, planning style, and operation type. Ecological attributes included the relative abundance of plant functional groups and categories of ground cover. We examined the environmental and management correlates of plant species and functional group composition using nonmetric multidimensional scaling and linear mixed models. After accounting for environmental variation across the study region, species composition did not differ between grazing management strategy and planning style. Operation type was significantly correlated with plant community composition. Integrated cow-calf plus yearling operations had greater annual and less key perennial cool-season grass species cover relative to cow-calf  only operations. Integrated cow-calf plus yearling ranches were able to more rapidly restock following drought compared with cow-calf operations. Differences in types of livestock operations contributed to variability in plant species composition across the landscape that may support diverse native faunal species in these rangeland ecosystems. Three broad themes emerged from the interviews: 1) long-term goals, 2) flexibility, and 3) adaptive learning. Stocking-rate decisions appear to be slow, path-dependent choices that are shaped by broader social, economic, and political dynamics. Ranchers described having greater flexibility in altering grazing strategies than ranch-level, long-term, annual stocking rates. These results reflect the complexity of the social-ecological systems ranchers navigate in their adaptive decision-making processes. Ranch decision-making process diversity within these environments precludes development of a single “best” strategy to manage livestock grazing.  相似文献   

14.
We examine how the system of grazing management of cattle in savanna rangelands affects the herd response to drought. We have used long-term time series data to evaluate the effects of management on drought-induced cattle mortality using traditional livestock management practices. There was no control of stocking densities, as compared to a government ranch where stocking densities would be adjusted in accordance with available pasture. We tested the responses under two scenarios. Scenario 1: Response of cattle herds to inter-annual rainfall variability (IRV) under a regulated grazing management system; this provides more reliable predictions of cattle population and performance in terms of herd mortality and calving rates than does the communal land use system. Scenario 2: Regardless of the management system, similar trends in cattle populations will be observed in response to IRV. The results of the study showed that fluctuations in cattle numbers, herd mortality and calving rates were highly correlated with IRV, with stronger linear impacts in accordance with scenario 2. In both management systems, cattle herd sizes and calving rates declined during periods of drought, followed by slow recovery. Cattle populations in Borana rangelands in southern Ethiopia did not recover for a period of two decades. We conclude that a management system based on control of stocking densities did not improve herd survival, as compared with traditional drought management strategies. This contradicts common expectations. Increased drought frequencies aggravated cattle mortality and lowered calving rates. The implication of the findings is that regardless of adjusted stocking density, livestock populations in the arid savanna ecosystems of southern Ethiopia remain at risk from climate change.  相似文献   

15.
A comprehensive understanding of multipaddock, rotational grazing management on rangelands has been slow to develop, and the contribution of adaptive management (Briske et al. 2011) and sufficient scale (Teague and Barnes 2017) have been identified as key omissions. We designed an experiment to compare responses of vegetation and cattle in an adaptively managed, multipaddock, rotational system with that of a season-long, continuous system at scales comparable with those of a working ranch. We hypothesized that 1) year-long rest periods in the adaptively managed, rotational pastures would increase the density and productivity of perennial C3 graminoids compared with continuously grazed pastures and 2) adaptive management, supported with detailed monitoring data, would result in similar cattle performance in the rotational as in the continuously grazed pastures. However, we found little supporting evidence for grazing management effects on C3 graminoid abundance or production under either above-average or below-average precipitation conditions during the 5-yr experiment. Furthermore, adaptive rotational grazing resulted in a 12–16% reduction in total cattle weight gain relative to continuous grazing each year. Our work shows that the implementation of adaptive management by a stakeholder group provided with detailed vegetation and animal monitoring data was unable to fully mitigate the adverse consequences of high stock density on animal weight gain. Under adaptive rotational grazing, C3 perennial grass productivity and stocking rate both increased following above-average precipitation. But when adaptive rotational management was directly compared with continuous grazing with the same increase in stocking rate, continuous grazing achieved similar vegetation outcomes with greater cattle weight gains. We suggest that managers in semiarid rangelands strive to maintain cattle at stock densities low enough to allow for maximal cattle growth rates, while still providing spatiotemporal variability in grazing distribution to enhance rangeland heterogeneity and long-term sustainability of forage production.  相似文献   

16.
Wildlife conservationists and agencies have recommended managing rangelands for vegetation heterogeneity to improve wildlife habitat, particularly for many grassland birds. However, range management focuses on livestock production and associated practices and structural items (fences, water developments) that are applied to improve livestock distribution. This article assesses the occurrence of livestock distribution–oriented grazing management in the spending and applied practices of the Natural Resources Conservation Service (NRCS), the federal agency charged with assisting private landowners with implementation of US Department of Agriculture conservation programs. NRCS applied practices and spending both suggest an emphasis on livestock distribution and associated structures, with almost 20 million ha of prescribed grazing systems, 10 000 km of fence, and 127 000 water facilities implemented in 17 western states with assistance from NRCS programs between 2004 and 2007. Ninety percent of funding for 2005 Conservation Security Program grazing enhancements supported investments or management related to livestock distribution. We suggest that increasing the emphasis of NRCS conservation programs and financial assistance on maintaining or increasing compositional and structural heterogeneity of vegetation, rather than on livestock distribution, could be an approach that unifies livestock production and wildlife habitat objectives. In particular, including vegetation heterogeneity as a central goal for upland wildlife habitat management could be a key opportunity to increase incentives for heterogeneity-promoting management on privately owned rangeland.  相似文献   

17.
In rangelands, grazing management is a main driver of rangeland condition. Due to masking effects of seasonal climate fluctuations, little is known about (dis)similarity of management effects on rangeland condition and forage provision across major dryland biomes. Taking a macro-ecological perspective, we analysed if management effects differed between South Africa’s central grassland and Kalahari savanna biomes. We recorded proxies of forage provision (phytomass, vegetation cover and their ratio) over five seasons, annual rainfall to account for seasonal climate fluctuations, and rangeland condition (through relative abundances of increaser and decreaser species). Regarding forage provision, we found effects of management for the savanna, where, irrespective of rainfall, rotational grazing management resulted in higher phytomass and phytomass–cover ratios than management with continuous grazing. In the grassland, however, this difference was only discernible for phytomass–cover ratio in two years with above-average antecedent rainfall. This suggests that management effects are biome-dependent and that modulating effects of annual rainfall are stronger in the grassland. In either biome, management effects on the dominance of increaser and decreaser species were negligible, i.e. rangeland condition did not differ across management types in either biome. We conclude that investigations on management effects should account for interactions with biome and rainfall.  相似文献   

18.
A survey was conducted between April and July 2007 to generate information on dry season feeding management and livestock poisoning in the southern rangelands of Ethiopia. A total of 119 pastoralists were interviewed using a semi-structured questionnaire. Moreover, additional information was obtained through informal discussions. The study revealed that pastoralists have rich knowledge of natural resource management and utilization and employ various strategies such as migration, collection of grasses and pods, and cutting branches to overcome feed scarcity during dry/drought periods. Migration of livestock and people to areas with better grazing is the widely used strategy. However, the implementation of this strategy is diminishing as a result of changes such as bush encroachment, expansion of settlements, and crop cultivation in dry-season grazing lands. The respondents also indicated the presence of poisonous plants in the rangeland, and about 20 such plants were identified by the respondents. Various species and classes of livestock are reported to be affected by toxic plants particularly in the dry and early rainy seasons when feed is in short supply. A more extensive survey is required to document all poisonous plants in the rangelands and to identify the major toxic principles in the different species. Future development interventions should consider the prevailing constraints and potentials of the rangelands with active participation of the pastoralists.  相似文献   

19.
Livestock and animal health development projects have not always led to substantial increases in animal productivity or in farmers' welfare. Some have even resulted in unsustainable systems, when they were not based on an understanding of (livestock) production systems. The multipurpose functions of livestock and complex relationships between the biological, technical and social components require a systems approach, whereby nutrition, animal health, breeding, biotechnology knowhow, inputs and technologies are used to optimise resource use. The challenge for developed and developing countries is to reverse the current degradation of the environment, and arrive at sustainable increases in crop and livestock production to secure present and future food supplies. For rural development, governments should show long term commitment and political will to support the rural population in development programmes, because smallholders (including women and landless livestock keepers) represent a large labour force in developing countries. Different systems need different approaches. Pastoral systems must focus on effective management of grazing pressure of the rangelands. Communal rangelands management involves not only the development and application of technologies (e.g. feedlots, vaccination campaigns), but also land tenure policies, institutional development, economic return and a reduction in the number of people depending upon livestock. Smallholder mixed farms must aim at intensification of the total production system, in which external inputs are indispensable, but with the emphasis on optimum input-output relationships by reducing resource losses due to poor management. Resource-poor farming systems must aim at the improved management of the various livestock species in backyards and very small farms, and proper packages for cattle, buffaloes, sheep, goats, rabbits and poultry should be developed. Specialised commercial livestock farming systems (poultry, pigs, dairy or meat) can only be sustainable with adequate marketing, supply of quality feed, veterinary services, labour, management and control of pollution. Animal health programmes play a keyrole in the proposed system approach.  相似文献   

20.
We evaluated Arizona Cooperative Extension’s Rangeland Monitoring Program with the use of focus groups and a self-administered mail survey of grazing permittees and natural resource agency employees. Our primary objectives were to 1) determine whether Extension is reaching its target audience, 2) describe the monitoring practices and attitudes of permittees and agency staff, 3) determine whether there is a relationship between permittees’ exposure to Cooperative Extension and their monitoring and management practices, and 4) identify the monitoring information needs and preferences of permittees and natural resource agency staff. We found that Arizona’s rangeland monitoring Extension program has been effective in reaching a large part of its target audience, and a significant proportion of Arizona permittees monitor on public, private, and state-owned rangelands. However, overall monitoring adoption rates remain low. Extension contact is associated with use of monitoring and other beneficial management practices, and permittees and agency employees report that monitoring increased their knowledge and led to changes in management. Monitoring by permittees improves agency–permittee relationships in many cases. Most permittees and agency employees believe that their respective peers are the most reliable source of monitoring information and prefer to receive information from Extension through face-to-face contact at workshops or personalized on-site assistance. The evaluation revealed important social dimensions of rangeland monitoring. Extension agents play a key role in facilitating the social process of monitoring, as well as providing technical training in monitoring skills. Further study is needed to investigate whether permittee monitoring actually leads to better management, improved economic returns, or increased tenure security.  相似文献   

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