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1.
Recent studies have shown an increasing trend in hydroclimatic disturbances like droughts, which are anticipated to become more frequent and intense under global warming and climate change. Droughts adversely affect the vegetation growth and crop yield, which enhances the risks to food security for a country like India with over 1.2 billion people to feed. Here, we compared the response of terrestrial net primary productivity (NPP) to hydroclimatic disturbances in India at different scales (i.e., at river basins, land covers, and climate types) to examine the ecosystems’ resilience to such adverse conditions. The ecosystem water use efficiency (WUEe: NPP/Evapotranspiration) is an effective indicator of ecosystem productivity, linking carbon (C) and water cycles. We found a significant difference (p < .05) in WUEe across India at different scales. The ecosystem resilience analysis indicated that most of the river basins were not resilient enough to hydroclimatic disturbances. Drastic reduction in WUEe under dry conditions was observed for some basins, which highlighted the cross‐biome incapability to withstand such conditions. The ecosystem resilience at land cover and climate type scale did not completely relate to the basin‐scale ecosystem resilience, which indicated that ecosystem resilience at basin scale is controlled by some other ecohydrological processes. Our results facilitate the identification of the most sensitive regions in the country for ecosystem management and climate policy making, and highlight the need for taking sufficient adaptation measures to ensure sustainability of ecosystems.  相似文献   

2.
This paper examines how oil palm migrant farmers in Papua New Guinea are responding to shortages of land for food gardening. Despite rapid population growth and planting nearly all of their land to oil palm, virtually all families continue to grow sufficient food for their families. The paper outlines the diverse range of adaptive strategies that households have employed to maintain food security, involving both intensification and innovation in farming systems. While gains from intensification have been significant and built resilience, they have been incremental, whereas innovation has been transformative and led to large gains in resilience. The adoption of more flexible land access arrangements on state leasehold land that ‘revive’ and adapt indigenous systems of land sharing and exchange that operated through kinship networks on customary land are innovative; they have increased the supply of land for food gardening thereby reducing risk for individual households and the broader smallholder community. The paper highlights the value of understanding farmer-driven innovations and the role of indigenous institutions and cultural values in sustaining and enhancing household food security.  相似文献   

3.
A better understanding of common property resource management systems and institutions is important for conservation and development, as fortress-based approaches towards conservation are increasingly questioned. This paper examines how an indigenous resource management system has operated and supported the protection of an Afro-alpine area in the Central Highlands of Ethiopia. The community was mainly concerned to regulate their own use of natural resources, including collection of firewood and thatch, and grazing by livestock. The original common property resource management system operated under a previously undescribed indigenous institution known as the Qero system, which was enforced through sanctions and punishments imposed by the community. The Qero system was suspended following the Agrarian Reform in 1975, which resulted in the breakdown of the traditional land tenure and land rights systems within Ethiopia. In the Central Highlands, user rights and management responsibility shifted to include formerly marginalized groups. Nevertheless, the common property management system has shown sufficient resilience to withstand these changes and pressures, and is still functioning with defined user groups and byelaws to regulate resource use and manage the area. Nevertheless, attitudes to current and future management are polarized between former and present managers of the common property regime.  相似文献   

4.
Connection with ancestral land is a central tenet of indigenous identity claims. In a departure from constructivist approaches to the role ancestral land in identity politics, this article focuses on the discursive and experiential manifestations of Mapuche theories of emplacement, according to which land is actively involved in the making of selves. By drawing upon the notion of tuwün, a term roughly translatable as place of origin, I argue that ancestral land acts as a potentiality of selfhood through the articulation of sameness and otherness within Mapuche society and with canonical others (winka). The ethnographic analysis of the relation between landscape and memory will illustrate how ancestral land works to situate the present between two poles of alterity, namely past dwellers and winka. Such a focus allows us to acknowledge the significance of ancestral land without resorting to genealogical and essentialist interpretations of indigenous subjectivity.  相似文献   

5.
A fundamental assumption in nearly all research on social adaptation to environmental change is that there is a concomitant and inverse relationship between human communities’ dependence upon particular natural resources affected by environmental change and those communities or societies’ resilience to disturbances. However, recent theoretical and empirical developments suggest resilience is a dynamic social process determined, in part, by the ability of communities to act collectively and solve common problems. The interactional approach to community is utilized to develop a framework whereby various patterns of social interaction define the process of social resilience. Data come from multiple mixed methods case studies of forest dependent communities within Southern Appalachia. The findings reveal varied processes of social resilience can occur in communities with similar levels of resource dependence; a community’s composition of internal social ties and their cross-scale linkages to external agencies and organizations define these processes.  相似文献   

6.
This study questions the customary thesis according to which the dominant status of the ashkenazim (European Jews) over the mizrachim (Middle Eastern and North African Jews) in Israeli society is to be explained by the earlier arrival of the former in Palestine. It does so by demonstrating that an early wave of Yemenite Jews, who arrived in Palestine simultaneously with the founding fathers, remained in a subservient social position. Archival sources, memoirs, and contemporary newspapers are used to explain the low status of Yemenite Jews by reference to the broader context of the Jewish‐Arab conflict as it took shape in Palestine's labour and land markets.  相似文献   

7.
In Indonesia, with the recent eruption of local struggles over resources and now with the new decentralization reforms, there is renewed interest in the role of customary adat institutional arrangements in village government, land tenure, and forest management. On the basis of research carried out in one locality in Sumatra over 1996–99, this article considers the nature of local institutional arrangements, how they have evolved under various conditions, their complex interaction with the parallel State order, their response to economic fluctuations, and how particular institutional patterns lead to certain environmental outcomes. This article finds that as farmers adjust to the economic and political dynamics and the changing scarcity and value of different resources in this site, the adat arrangements are constantly renegotiated. Adat customary orders are tied to local notions of identity and associated notions of appropriateness, and as such constitute patterns of social ordering associated with both implicit deeply held social norms and more explicit rules. Considering the institutional pluralism characteristic of this area, this article concludes that, while the State and adat regimes often compete to control the direction of social change, they also constantly make accommodations, and in some respects need to be considered as mutually adjusting, intertwined orders.  相似文献   

8.
Aim The slowly dispersing Greek land snail species Isabellaria (Carinigera) pharsalica ( Nordsieck, 1974 ) can be readily distinguished from related species of the subgenus Carinigera on biogeographical grounds, i.e. by a separation of nearly 200 km. Nevertheless, I. pharsalica shows overlap in shell morphology with Isabellaria (Carinigera) buresi (A. J. Wagner, 1927). The aim of this paper is to study the interrelationships and phylogeography of I. pharsalica and selected I. buresi subspecies, in order to reconcile these apparently contradictory observations. Location Northern Greece, Macedonia, Serbia and southern Bulgaria. Methods Mitochondrial COI genealogical interrelationships were studied for specimens of I. pharsalica, selected I. buresi subspecies and other related Isabellaria species. Results COI sequences of I. pharsalica constitute a clade nested among sequences of I. buresi from north‐eastern Greece and adjacent Bulgaria. The genetic divergence among the I. pharsalica sequences is remarkably low compared to the divergence among the I. buresi sequences. Main conclusions I. pharsalica descended from specimens of I. buresi that dispersed into Thessaly, and it should therefore be classified as a subspecies within I. buresi. This find is in line with the conchological similarities between I. buresi pharsalica and other I. buresi subspecies. Given the low vagility of the snails in question and the c. 200‐km separation by land and sea between the ranges of I. buresi pharsalica and the combined range of the other I. buresi subspecies, passive dispersal of the I. pharsalica ancestors is most likely. Since the inferred area of origin of these hypothetical ancestors of I. buresi pharsalica nearly coincides with an ancient marble quarry, human‐aided dispersal during marble transport offers a possible explanation for I. buresi pharsalica's erratic distribution.  相似文献   

9.
Climate change is affecting the distribution of species and the functioning of ecosystems. For species that are slow growing and poorly dispersed, climate change can force a lag between the distributions of species and the geographic distributions of their climatic envelopes, exposing species to the risk of extinction. Climate also governs the resilience of species and ecosystems to disturbance, such as wildfire. Here we use species distribution modelling and palaeoecology to assess and test the impact of vegetation–climate disequilibrium on the resilience of an endangered fire‐sensitive rainforest community to fires. First, we modelled the probability of occurrence of Athrotaxis spp. and Nothofagus gunnii rainforest in Tasmania (hereon “montane rainforest”) as a function of climate. We then analysed three pollen and charcoal records spanning the last 7,500 cal year BP from within both high (n = 1) and low (n = 2) probability of occurrence areas. Our study indicates that climatic change between 3,000 and 4,000 cal year bp induced a disequilibrium between montane rainforests and climate that drove a loss of resilience of these communities. Current and future climate change are likely to shift the geographic distribution of the climatic envelopes of this plant community further, suggesting that current high‐resilience locations will face a reduction in resilience. Coupled with the forecast of increasing fire activity in southern temperate regions, this heralds a significant threat to this and other slow growing, poorly dispersed and fire sensitive forest systems that are common in the southern mid to high latitudes.  相似文献   

10.
This article concerns the use of narrative and genealogical frameworks among sertanejos, the inhabitants of the hinterlands (sertão) of Pernambuco in the Northeast of Brazil, in the process of grouping and differentiating families. It explores how accounts produced by different people are linked by shared memories of past conflicts – such as cangaço and questões de família (lit. ‘family issues’). Through conceived and lived relationships among relatives and the correlated concepts of ‘blood’ and ‘race’ current in this social formation, I look to identify the different meanings attributed to time and space, inscribed in the collective memory, and implicated in the moving configurations of ‘family’ in a cognatic universe.  相似文献   

11.
Summary The pallida gene of Antirrhinum majus governs anthocyanin production. The nature of the mutability displayed by its unstable allele pal-rec was dramatically altered following crosses between two pal-rec pal-rec lines with certain separately maintained lines. In both cases a minority of progeny in F1 or F2 revealed unprecedented infrequent mutability termed Low mutability. These Low plants and their sibs showed many areas of contrasting mutability superimposed on their initial mutability level. This frequent shifting and Low mutability persisted through several generations of offspring obtained by both selfing and crossing to a non-mutable tester line. Evidence is presented to suggest a hypothesis that the two features of altered mutability are two aspects of the same phenomenon caused by joint action of two independent factors J and k, one contributed by each parental line at the outcross.A separate gene, eosinea, governs anthocyanin type, eos eos plants having pelargonin in place of wild-type magenta cyanin. In addition to the previously known simple depression of pal-rec to Pal mutation frequency in eos eos plants, eos also influences the action of J and k when heterozygous (i.e. Eos eos), thus contributing a basal and a third tier of control influencing mutability of pal-rec.Three levels of control are thus identified, the middle tier being governed by the partnership of J and k producing not a simple change but a complex mutability of mutability.  相似文献   

12.
This paper examines the indigenous land and forest management systems of the community of seven Iban longhouses whose territories comprise the area of Batang Ai National Park in Sarawak, Malaysia. It also discusses the integrated conservation and development program (ICDP) at the park. This project is attempting to work within the existing system of customary law to build on traditional legislative infrastructure and management practices, in order to enlist the cooperation of local people and their leaders in implementing a new conservation strategy. In addition to reinforcing local authority, park planners recognize the need for local people to be given strong incentives to participate in co-management of the protected area. This paper argues that, despite a history of conflict with indigenous peoples, State officials have in this instance demonstrated a willingness to work with local people and community leaders. At the same time, they are encouraging community development, helping people to find alternatives to activities that threaten the park's wildlife.  相似文献   

13.
Summary A case of genetic variegation discovered at the opaque-2 locus of maize that includes a two-element system with a receptor and regulatory element is described. The somatic mutability depends on the existence of two genetic factors: a responsive allele (with receptor element), o2m(r), and a regulatory element, Bg, that induces mutability of o2m(r). In the absence of Bg, o2m(r) is indistiguishable from the recessive alleles of the O2 locus; in the presence of the regulatory element, o2m(r) mutates giving rise to sectors of flint-like endosperm in an opaque back-ground. The regulatory element Bg may be located independently or at the controlled locus. The genetic properties of the new system, somatic mutability, transposition, existence of different patterns of mutability, are apparently similar to those previously described in maize for the classical systems of controlling elements. In addition, the recovery of the o2 mutability from crosses between spontaneous o2 alleles suggests that transposable genetic elements may be involved in the origin of natural mutability.  相似文献   

14.
Coral reefs are increasingly threatened by various disturbances, and a critical challenge is to determine their ability for resistance and resilience. Coral assemblages in Moorea, French Polynesia, have been impacted by multiple disturbances (one cyclone and four bleaching events between 1991 and 2006). The 1991 disturbances caused large declines in coral cover (~51% to ~22%), and subsequent colonization by turf algae (~16% to ~49%), but this phase-shift from coral to algal dominance has not persisted. Instead, the composition of the coral community changed following the disturbances, notably favoring an increased cover of Porites, reduced cover of Montipora and Pocillopora, and a full return of Acropora; in this form, the reef returned to pre-disturbance coral cover within a decade. Thus, this coral assemblage is characterized by resilience in terms of coral cover, but plasticity in terms of community composition.  相似文献   

15.
Parallels exist between the academic theory of a dwelling approach to resilience and the Indigenous Stewardship Model developed on the Pine Ridge Indian Reservation in South Dakota. In both approaches, sustainable resource management depends on a practical environmentalism that creates linkages between local community members and their surrounding ecosystem. Research on the Pine Ridge Indian Reservation reveals that Lakota people possess a conservation ethic that stems from their physical connection to place. However, tribal, state, and federal land policies create structural barriers that reduce access of Lakota households to the land, which in turn reduces adaptability and resilience in their ecological practice. To overcome these barriers, Lakota households envision local stewardship of reservation lands and resources. Particular emphasis is placed on the intergenerational transfer of knowledge to Lakota youth, to transcend local and political conflict, and to reestablish social and cultural relationships with the reservation’s ecology.  相似文献   

16.
Identifying resilience mechanisms to recurrent ecosystem perturbations   总被引:1,自引:0,他引:1  
The complex nature of ecological systems limits the unambiguous determination of mechanisms that drive resilience to natural disturbance or anthropogenic stress. Using eight-year time series data from boreal lakes with and without bloom formation of an invasive alga (Gonyostomum semen, Raphidophyceae), we studied resilience of phytoplankton communities in relation to recurring bloom impacts. We first characterized phytoplankton community dynamics in both lake types using univariate metrics of community structure (evenness, species richness, biovolume and Simpson diversity). All metrics, except species richness, were substantially altered and showed an inherent stronger variability in bloom lakes relative to reference lakes. We assessed resilience mechanisms using a multivariate time series modelling technique. The models captured clear successional dynamics of the phytoplankton communities in all lakes, whereby different groups of species were substituted sequentially over the ice-free period. The models also identified that G. semen impacts in bloom lakes were only manifested within a single species group, not across species groups, highlighting the rapid renewal of the phytoplankton communities upon bloom collapse. These results provide empirical support of the cross-scale resilience model. Cross-scale resilience could provide an explanation for the paradox that similar species richnesses are seen in bloom-forming lakes and reference lakes despite the clear difference between the community features of the two different sets of lakes investigated.  相似文献   

17.
This study describes the unusual growth forms of Chara (Charales) in a natural terrestrial environment in a temperate region (southern Siberia). Chara vulgaris had a moss‐like habit and grew on wet soil in small compact turfs probably germinated from oospores. The upper branchlets were curved in a hook‐liked manner and convergent above the apex of the thallus. The lowest internode and branchlets of fertile plants were ecorticate, whereas all other parts were normally corticated; the completely ecorticate plants were sterile. The terrestrial growth of charophytes had an irregular appearance but was successfully maintained in culture, providing a potential model of the first steps of land colonization by the ancestors of embryophytes.  相似文献   

18.
ObjectiveTo assess the association between social determinants of health (SDH) and resilience in older people during the first period of confinement in the COVID-19 pandemic in Chile.Materials and methodsAn observational study with a cross-sectional design was conducted using a nationally representative survey data-set. In this survey, using a systematic randomization process, a subsample of people aged ≥60 years from the community were interviewed by telephone during the first wave of the COVID-19 pandemic in Chile. Resilience was assessed using the Brief Resilient Coping Scale (BRCS) and depressive symptoms using the Patient Health Questionnaire (PHQ-9) scale. The SDH considered were: age, sex, educational level, employment status, social isolation, loneliness, discontent with housing and health care needs.ResultsA total sample of 582 persons was obtained. The mean age was 71 years (SD: 7.64; 69% women). A significant association was obtained between low resilience and the following conditions: loneliness (OR: 1.776 [95% CI: 1.146–2.751]), high risk of social isolation (OR: 1.667 [95% CI: 1.149-2.419]), and depressive symptoms (OR: 2.602 [95% CI: 1.795-3.774]). Female gender was a protective factor (OR: 0.589 [95% CI: 0.406-0.855]).ConclusionThe SDH, such as loneliness and social isolation, are factors associated with low resilience in older people during the COVID-19 pandemic and may be taken into account in planning public health intervention strategies.  相似文献   

19.
Summary The presence of the histidine operator-constitutive mutationhis01242 increases UV-induced mutability within the histidine operon ofSalmonella typhimurium. The rate of reversion ofhisC andhisF ochre and frameshift mutants is increased 5- to 8-fold when these mutations are coupled withhis01242 which causes 15-fold derepression of the operon. The effect does not extend to the whole chromosome since the rate of UV-induced mutability at the unlinked streptomycin locus is the same in the strains carryinghis0 + orhis01242 alleles. The same phenomenon was observed in Hcr strains.  相似文献   

20.
This paper argues that due to the co-evolution of biological and cultural diversity, a meaningful study of biodiversity must be positioned within complex social-ecological systems. A complex systems framework is proposed for conceptualising the study of social-ecological systems. A case study approach is adopted whereby changes in biodiversity on the Causse Méjan, France, are linked with changes in society, land use, agricultural practices and policies. We argue that ecological and social resilience is linked through the dependence on ecosystems of communities, and in turn by the influence of institutional structures, including market forces, on the use of natural resources. Within a non-equilibrium evolutionary perspective, we highlight the difficulty of choosing a landscape and biodiversity of reference and postulating that it is in equilibrium with a type of social organisation. We conclude by exploring an ‘adaptive management’ approach to the management of the biodiverse landscape studied.  相似文献   

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