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1.
Sci Total Environ ; 897: 165433, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37437641

RESUMO

Conflicts between economic development and conservation are increasingly hampering efforts to restore imperiled wildlife populations. Public opinion can influence how these conflicts translate into conservation actions, encouraging stakeholders to express their views through various public channels. The outcome of these campaigns typically remains unknown. Via an online survey, we collected to the opinion of 1000 citizens of Québec, Canada, regarding the ongoing conflict between logging and the conservation of at-risk caribou populations (Rangifer tarandus). We found that people expect conservation actions that are sufficient to recover caribou populations, even if millions of government investment are required and jobs are lost in the process. When respondents learned that academic caribou researchers indicated that the two management strategies being studied by government would be insufficient for population recovery, one-third withdrew their support for either strategy. Age, gender and education all explain variation in public opinion, but it was the region of residence that most consistently explained variation in opinion. Residents of caribou-inhabited regions were less concerned about caribou conservation and more supportive of forestry than residents of other regions, reflecting regional differences in expected economic impacts of conservation, not negative interactions with caribou. In fact, most people supported strong conservation actions for the recovery of caribou populations, regardless of their socio-demographics. Our analysis provides general insights into how public opinion on the trade-off between conservation and economy is influenced by socio-demographics and scientific conclusions. We found that current government conservation actions (or lack thereof) are not in line with mainstream public opinion. Moreover, we show that making species at-risk lists does not ensure that the species will benefit from strong conservation actions without lengthy delays, even for a high-profile, flagship species like caribou. This observation echoes concerns about the fate of less charismatic, at-risk species, and thus about future biodiversity conservation efforts.


Assuntos
Rena , Humanos , Animais , Conservação dos Recursos Naturais , Taiga , Opinião Pública , Animais Selvagens , Ecossistema
2.
Ambio ; 52(4): 757-768, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36759433

RESUMO

Although biodiversity is crucial for Sustainable Development Goals (SDGs), following the current trajectory, we risk failing SDG 15. Using a new indicator quantifying the loss of functional habitat (habitat that is simultaneously suitable and well-connected), we show that the real impact of renewable energy is far larger than previously assumed. Specifically, we estimate that the construction of hydropower reservoirs in south Norway caused a loss of ca. 222 km2 of functional habitat for wild reindeer (Rangifer tarandus)-which is far larger than assumed based on land inundation indices (110 km2). Fully mitigating these impacts is challenging: scenario analyses reveal that the measures proposed by societal actors would yield only a fraction of the habitat lost (2-12 km2) and could cause trade-off risks with other SDGs. Using indices of functional connectivity is crucial for environmental impact assessments, as entire ecological networks for several species can be affected far beyond the reservoirs.


Assuntos
Rena , Desenvolvimento Sustentável , Animais , Ecossistema , Biodiversidade , Noruega
3.
Scand J Public Health ; 51(7): 1009-1015, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35603548

RESUMO

AIMS: This study aimed to compare the concentrations of heavy metals in reindeer and cow meat and offal originating from the Nenets Autonomous Okrug, Northwestern Russia, and to assess the risk to the health of the indigenous population associated with heavy metal intake due to the consumption of reindeer and cow. METHODS: Lead, cadmium, mercury, and arsenic concentrations were measured in 39 muscle, 15 liver, and 14 kidney samples from reindeer and 33, 18, and 12 corresponding samples from cow in 2014-2016 using atomic absorption spectrometry. Estimated daily intake of investigated heavy metals, hazard quotient, hazard index and cancer risk were calculated. RESULTS: Mean cadmium and mercury concentrations in reindeer liver and kidney exceeded the maximum permissible levels for bovine animals. However, the estimated daily intakes of heavy metals through consumption of reindeer and cow meat and offal were lower than tolerable daily intakes. Hazard quotient and hazard index values for heavy metals in reindeer and cow samples were <1. Hazard index values were in descending order: reindeer kidney (0.389)>reindeer muscle (0.382)>cow muscle (0.088)>reindeer liver (0.051)>cow kidney (0.012)>cow liver (0.004). The cancer risk related to the consumption of reindeer and cow meat and offal did not exceed acceptable levels. CONCLUSIONS: There is no human health risk associated with heavy metal intake due to the consumption of reindeer and cow meat and offal originating from the Nenets Autonomous Okrug.


Assuntos
Mercúrio , Metais Pesados , Neoplasias , Rena , Feminino , Humanos , Bovinos , Animais , Cádmio/análise , Metais Pesados/análise , Mercúrio/análise , Medição de Risco , Carne/análise , Contaminação de Alimentos/análise
4.
Ecol Appl ; 33(1): e2719, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36380453

RESUMO

Wild and semidomesticated reindeer are one of the key species in Arctic and subarctic areas, and their population dynamics are closely tied to winter conditions. Difficult snow conditions have been found to decrease the calving success and survivability of reindeer, but the economic effects of variation in winter conditions on reindeer husbandry have not been studied. In this study, we combine state-of-the-art economic-ecological modeling with the analysis of annual reindeer management reports from Finland. These contain local knowledge of herding communities. We quantify the occurrence probabilities of different types of winters from annual management reports and analyze the effects of this variation in winter conditions on reindeer husbandry using an age- and sex-structured bioeconomic reindeer-lichen model. Our results show that difficult winters decrease the net revenues of reindeer husbandry. However, they also protect lichen pastures from grazing, thereby increasing future net revenues. Nonetheless, our solutions show that the variability of winter conditions overall decrease the net income of herders compared to constant winter conditions. Low lichen biomass appears to make reindeer management more sensitive to the effects of difficult winter conditions. We also found that it is economically sensible to use supplementary feeding during difficult winters, but the net revenues still decrease compared to average winters because of the high feeding costs. Overall, our analysis suggests that the increasing variability of winter conditions due to climate change will decrease net revenues in reindeer husbandry. This decrease will still occur even if the most extreme effects of climate change do not occur. This study shows that combining a state-of-the-art bioeconomic model and practitioner knowledge can bring compatible insights, ideas, results, and a bottom-up perspective to the discussion.


Assuntos
Mudança Climática , Rena , Animais , Finlândia , Líquens , Estações do Ano , Neve , Criação de Animais Domésticos/economia , Criação de Animais Domésticos/normas
5.
Nat Hum Behav ; 6(12): 1723-1730, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36203052

RESUMO

The success and failure of past cultures across the Arctic was tightly coupled to the ability of past peoples to exploit the full range of resources available to them. There is substantial evidence for the hunting of birds, caribou and seals in prehistoric Greenland. However, the extent to which these communities relied on fish and cetaceans is understudied because of taphonomic processes that affect how these taxa are presented in the archaeological record. To address this, we analyse DNA from bulk bone samples from 12 archaeological middens across Greenland covering the Palaeo-Inuit, Norse and Neo-Inuit culture. We identify an assemblage of 42 species, including nine fish species and five whale species, of which the bowhead whale (Balaena mysticetus) was the most commonly detected. Furthermore, we identify a new haplotype in caribou (Rangifer tarandus), suggesting the presence of a distinct lineage of (now extinct) dwarfed caribou in Greenland 3,000 years ago.


Assuntos
DNA Antigo , Rena , Animais , DNA Antigo/análise , Groenlândia , Arqueologia
6.
Biometrics ; 78(1): 286-299, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33270218

RESUMO

This article presents a new method for modelling collective movement in continuous time with behavioural switching, motivated by simultaneous tracking of wild or semi-domesticated animals. Each individual in the group is at times attracted to a unobserved leading point. However, the behavioural state of each individual can switch between 'following' and 'independent'. The 'following' movement is modelled through a linear stochastic differential equation, while the 'independent' movement is modelled as Brownian motion. The movement of the leading point is modelled either as an Ornstein-Uhlenbeck (OU) process or as Brownian motion (BM), which makes the whole system a higher-dimensional Ornstein-Uhlenbeck process, possibly an intrinsic non-stationary version. An inhomogeneous Kalman filter Markov chain Monte Carlo algorithm is developed to estimate the diffusion and switching parameters and the behaviour states of each individual at a given time point. The method successfully recovers the true behavioural states in simulated data sets , and is also applied to model a group of simultaneously tracked reindeer (Rangifer tarandus).


Assuntos
Movimento , Rena , Algoritmos , Animais , Cadeias de Markov , Método de Monte Carlo
7.
J Anim Ecol ; 91(1): 61-73, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34543441

RESUMO

The cost of reproduction on demographic rates is often assumed to operate through changing body condition. Several studies have found that reproduction depresses body mass more if the current conditions are severe, such as high population densities or adverse weather, than under benign environmental conditions. However, few studies have investigated the association between the fitness components and body mass costs of reproduction. Using 25 years of individual-based capture-recapture data from Svalbard reindeer Rangifer tarandus platyrhynchus, we built a novel Bayesian state-space model that jointly estimated interannual change in mass, annual reproductive success and survival, while accounting for incomplete observations. The model allowed us to partition the differential effects of intrinsic and extrinsic factors on both non-reproductive mass change and the body mass cost of reproduction, and to quantify their consequences on demographic rates. Contrary to our expectation, the body mass cost of reproduction (mean = -5.8 kg) varied little between years (CV = 0.08), whereas the between-year variation in body mass changes, that were independent of the previous year's reproductive state, varied substantially (CV = 0.4) in relation to autumn temperature and the amount of rain-on-snow in winter. This body mass loss led to a cost of reproduction on the next reproduction, which was amplified by the same environmental covariates, from a 10% reduction in reproductive success in benign years, to a 50% reduction in harsh years. The reproductive mass loss also resulted in a small reduction in survival. Our results show how demographic costs of reproduction, driven by interannual fluctuations in individual body condition, result from the balance between body mass costs of reproduction and body mass changes that are independent of previous reproductive state. We illustrate how a strong context-dependent fitness cost of reproduction can occur, despite a relatively fixed body mass cost of reproduction. This suggests that female reindeer display a very conservative energy allocation strategy, either aborting their reproductive attempt at an early stage or weaning at a relatively constant cost. Such a strategy might be common in species living in a highly stochastic and food limited environment.


Assuntos
Herbivoria , Rena , Animais , Regiões Árticas , Teorema de Bayes , Feminino , Reprodução , Estações do Ano
8.
Am J Hum Biol ; 34(4): e23676, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34520587

RESUMO

OBJECTIVE: High levels of total energy expenditure (TEE, kcal/day) have been documented among numerous human populations such as tropical climate horticulturalists and high-altitude agriculturalists. However, less work has been conducted among highly physically active cold climate populations. METHODS: In October 2018, TEE was measured using the doubly labeled water (TEEDLW , N = 10) and flex-heart rate methods (TEEHR , N = 24) for 6-14 days among reindeer herders (20-62 years) in northern Finland during an especially physically demanding, but not seasonally representative, period of the year for herders-the annual reindeer herd roundup. Self-reported dietary intake was also collected during TEE measurement periods. TEE was then compared to that of hunter gatherer, farming, and market economies. RESULTS: During the herd roundup, herders expended a mean of 4183 ± 949 kcal/day as measured by the DLW method, which was not significantly different from TEEHR . Mean caloric intake was 1718 ± 709 kcal/day, and was significantly lower than TEEDLW and TEEHR (p < .001). Herder TEEDLW was significantly higher than that of hunter gatherer (p = .0014) and market (p < .0014) economy populations; however, herder TEEDLW was not different from that of farming populations (p = .91). CONCLUSION: High TEE and low caloric intake among herders reflect the extreme demands placed on herders during the annual herd round up. Although TEEDLW was similar between cold climate herders and hot climate farming populations, there are likely differences in how that TEE is comprised, reflecting the local ecologies of these populations.


Assuntos
Rena , Animais , Ingestão de Energia , Metabolismo Energético/fisiologia , Finlândia , Humanos , Água
9.
Ecol Appl ; 30(6): e02132, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32297391

RESUMO

Some species are valued for their direct usefulness to society, through immediate financial returns from market activities such as harvesting or ecotourism. But many are valued for their passive usefulness, i.e., their mere existence contributes to supporting, regulating or cultural environmental services that support human well-being. Hence, there is inherent social value to conserving such species as natural assets. However, such species are seldom priced as natural assets, and thus not accounted for in sustainability wealth measures because deriving non-market prices is challenging. We overcome this limitation by presenting a new approach for natural asset pricing of species with passive value that can be incorporated into national sustainability wealth accounting. We explicitly consider the relationship between prevailing institutions, species interactions, and ecosystem dynamics. Our approach is illustrated with the case of threatened woodland caribou in the Alberta Oil Sands. We show that conservation can be considered an investment while destructive activities can lead to a loss or conservation debt; and forgoing destructive activities can be considered a capital gain, increasing future wealth. Our approach reveals that caribou conservation in Alberta is leading to a conservation debt on the order of CA$800 million.


Assuntos
Ecossistema , Rena , Alberta , Animais , Conservação dos Recursos Naturais , Humanos , Campos de Petróleo e Gás
10.
PLoS One ; 15(3): e0229555, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32160207

RESUMO

A significant challenge of conservation biology is to preserve species in places where their critical habitat also attracts significant economic interest. The problem is compounded when species distributions occur across large spatial extents. Threatened boreal caribou (Rangifer tarandus caribou) epitomize this problem: their critical habitat encompasses a vast expanse of forest that also supplies much of Canada's merchantable timber. Boreal caribou were protected under the Canada Species at Risk Act in 2003. We investigated putative drivers of reduced disturbance for caribou habitat since then. Where the cumulative logging footprint slowed within caribou habitat, this has resulted neither from decreases in annual allowable cut of timber nor the creation or expansion of protected areas. Rather, it has fluctuated with the American economy relative to that of Canada. For each $0.05 US lost over the $CAD, 129 km2 of caribou habitat was not disturbed by logging in a given year. Recent population declines have been occurring even though logging typically remained at <70% of allowed levels. Our study raises concerns about how caribou are functionally being conserved under the current application of existing legislation. In this globalized world, the economy of foreign nations is increasingly likely to govern national conservation objectives.


Assuntos
Conservação dos Recursos Naturais/economia , Espécies em Perigo de Extinção/economia , Cooperação Internacional/legislação & jurisprudência , Animais , Canadá , Conservação dos Recursos Naturais/métodos , Ecossistema , Florestas , Dinâmica Populacional , Rena , Estados Unidos
11.
Oecologia ; 189(3): 601-609, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30725371

RESUMO

The costs of reproduction are important in shaping individual life histories, and hence population dynamics, but the mechanistic pathways of such costs are often unknown. Female reindeer have evolved antlers possibly due to interference competition on winter-feeding grounds. Here, we investigate if variation in antler size explains part of the cost of reproduction in late winter mass of female reindeer. We captured 440 individual Svalbard reindeer a total of 1426 times over 16 years and measured antler size and body mass in late winter, while presence of a 'calf-at-heel' was observed in summer. We found that reproductive females grew smaller antlers and weighed 4.3 kg less than non-reproductive females. Path analyses revealed that 14% of this cost of reproduction in body mass was caused by the reduced antler size. Our study is therefore consistent with the hypothesis that antlers in female Rangifer have evolved due to interference competition and provides evidence for antler growth as a cost of reproduction in females. Antler growth was constrained more by life history events than by variation in the environment, which contrasts markedly with studies on male antlers and horns, and hence increases our understanding of constraints on ornamentation and life history trade-offs.


Assuntos
Chifres de Veado , Cervos , Cornos , Rena , Animais , Feminino , Masculino , Reprodução , Svalbard
12.
Ambio ; 48(6): 649-660, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30182248

RESUMO

The socioeconomic causes of land use change are complex. They are highly context dependent, but most often studied through case studies. Here, we use a quasi-experimental paired block design to investigate whether better access to wage income leads to more visible land use around 28 settlements in six regions of the circumpolar Arctic. We mapped visible land use on high-resolution satellite images taken both close to the settlements, and in a more remote area of extensive land use, and payed special attention to tracks of off-road vehicles (ORV). Despite considerable differences among regions, there was an overall positive relationship between better access to wage income and land use. Reindeer herding was also associated with more visible use, in particular ORV tracks. These results suggest that access to wage income in the mixed subsistence-cash communities of the Arctic could lead to more local use related to harvesting and reindeer herding.


Assuntos
Desenvolvimento Econômico , Rena , Animais , Regiões Árticas
13.
J Environ Manage ; 218: 103-117, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29674158

RESUMO

Tradeoffs between cost and recovery targets for boreal caribou herds, threatened species in Alberta, Canada, are examined using a dynamic cost minimization model. Unlike most approaches used for minimizing costs of achieving threatened species targets, we incorporate opportunity costs of surface (forests) and subsurface resources (energy) as well as direct costs of conservation (habitat restoration and direct predator control), into a forward looking model of species protection. Opportunity costs of conservation over time are minimized with an explicit target date for meeting species recovery targets; defined as the number of self-sustaining caribou herds, which requires that both habitat and population targets are met by a set date. The model was run under various scenarios including three species recovery criteria, two oil and gas price regimes, and targets for the number of herds to recover from 1 to 12. The derived cost curve follows a typical pattern as costs of recovery per herd increase as the number of herds targeted for recovery increases. The results also show that the opportunity costs for direct predator control are small compared to habitat restoration and protection costs. However, direct predator control is essential for meeting caribou population targets and reducing the risk of extirpation while habitat is recovered over time.


Assuntos
Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Rena , Alberta , Animais , Ecossistema , Florestas
14.
Ambio ; 46(6): 644-654, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28361495

RESUMO

This paper studies the practice of semi-domestic reindeer (Rangifer t. tarandus) herding in Finnmark county in northern Norway. In this area, the Saami reindeer herders compete for space and grazing areas and keep large herds, while at the same time, the reindeer population is heavily exposed to carnivore predation by the lynx (Lynx lynx), the wolverine (Gulo gulo), and the golden eagle (Aquila chrysaetos). It is demonstrated that predation actually may improve the economic lot of livestock holders in this unmanaged local common setting. There are ecological as well as economic reasons as to why this happens. The ecological reason is that predation compensates for natural mortality; that is, increased predation reduces natural mortality, indicating that the net loss due to predation actually may be quite small. When predation reduces livestock density, the feeding conditions of the animals will improve, resulting in increased livestock weight and higher per animal slaughter value. At the same time, a smaller stock reduces the operating costs of the herders.


Assuntos
Gado , Rena , Animais , Economia , Feminino , Noruega
15.
J Toxicol Environ Health A ; 79(16-17): 762-97, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27556568

RESUMO

Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy (TSE) found in both farmed and wild deer, elk, and moose in the United States and Canada. Surveillance efforts in North America identified the geographical distribution of the disease and mechanisms underlying distribution, although the possibility of transmission to other cervids, including caribou, and noncervids, including humans, is not well understood. Because of the documented importance of caribou (Rangifer tarandus) to human populations in the northern regions of Canada, a risk-management strategy for CWD requires an understanding of the extent of potential dietary exposure to CWD. Secondary 24-h dietary recalls conducted among Inuvialuit and Inuit in 4 communities in the Northwest Territories and Nunavut were employed in this study. Econometric demand systems were estimated to model the impacts of individual- and community-level socioeconomic characteristics on expenditures on caribou and other foods, in order to examine the households' ability to consume other foods in response to changing levels of caribou consumption. Thirty-five percent of respondents reported consuming caribou in the survey period, and caribou comprised, on average, 26% of daily dietary intake by weight, or approximately 65 g/d, across individuals in the 4 communities. Consuming caribou was also shown to exert positive impacts on dietary quality, as measured by calorie intake and dietary diversity. Communities with less access to employment, income and food stores are predicted to be constrained in their ability to obtain an adequate diet in the event of scarcity of caribou meat.


Assuntos
Dieta , Rena , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Econômicos , Territórios do Noroeste , Nunavut , Risco , Doença de Emaciação Crônica/transmissão , Adulto Jovem , Yukon
16.
Biometrics ; 72(2): 315-24, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26812666

RESUMO

This article presents a new approach to modeling group animal movement in continuous time. The movement of a group of animals is modeled as a multivariate Ornstein Uhlenbeck diffusion process in a high-dimensional space. Each individual of the group is attracted to a leading point which is generally unobserved, and the movement of the leading point is also an Ornstein Uhlenbeck process attracted to an unknown attractor. The Ornstein Uhlenbeck bridge is applied to reconstruct the location of the leading point. All movement parameters are estimated using Markov chain Monte Carlo sampling, specifically a Metropolis Hastings algorithm. We apply the method to a small group of simultaneously tracked reindeer, Rangifer tarandus tarandus, showing that the method detects dependency in movement between individuals.


Assuntos
Modelos Biológicos , Movimento , Algoritmos , Animais , Ciências Biocomportamentais , Simulação por Computador , Cadeias de Markov , Método de Monte Carlo , Rena
17.
Environ Manage ; 57(4): 770-83, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26645074

RESUMO

In the management of natural resources, conflicting interests and objectives among different stakeholders often need to be considered. Here, we examine how two contrasting management scenarios of boreal forests in northern Sweden differ in their consequences on forest structural composition and the economic gains at harvest. Management strategies prioritize either (i) forest characteristics that promote grazing resources for reindeer herded by the indigenous Sámi, or (ii) timber production as practiced in Sweden today. When prioritizing reindeer grazing, forest stands develop a higher abundance of older age classes with larger trees and lower stem density, which reduces harvest and revenue levels by approximately 20% over a 100-year period. The differences between these strategies illustrate the complexity in finding a trade-off for coexistence between industrial land users and other livelihoods that share the same landscape. Political support and institutional solutions are necessary to initiate changes in policy in finding such trade-offs in the management of environmental resources and thereby influence the optimal distribution of costs and benefits between different actors.


Assuntos
Conservação dos Recursos Naturais , Agricultura Florestal , Rena , Criação de Animais Domésticos , Animais , Conflito Psicológico , Análise Custo-Benefício , Suécia
18.
PLoS One ; 10(6): e0127586, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26061003

RESUMO

The winter diet of barren-ground caribou may affect adult survival, timing of parturition, neonatal survival, and postpartum mass. We used microhistological analyses and hormone levels in feces to determine sex-specific late-winter diets, pregnancy rates, group composition, and endocrine-based measures of physiological and nutritional stress. Lichens, which are highly digestible but contain little protein, dominated the diet (> 68%) but were less prevalent in the diets of pregnant females as compared to non-pregnant females and males. The amount of lichens in the diets of pregnant females decreased at higher latitudes and as winter progressed. Pregnancy rates (82.1%, 95% CI = 76.0 - 88.1%) of adult cows were within the expected range for a declining herd, while pregnancy status was not associated with lichen abundance in the diet. Most groups (80%) were of mixed sex. Male: female ratios (62:100) were not skewed enough to affect the decline. Levels of hormones indicating nutritional stress were detected in areas of low habitat quality and at higher latitudes. Levels of hormones indicated that physiological stress was greatest for pregnant cows, which faced the increasing demands of gestation in late winter. These fecal-based measures of diet and stress provided contextual information for the potential mechanisms of the ongoing decline. Non-invasive techniques, such as monitoring diets, pregnancy rates, sex ratios and stress levels from fecal samples, will become increasingly important as monitoring tools as the industrial footprint continues to expand in the Arctic.


Assuntos
Dieta , Taxa de Gravidez , Rena/fisiologia , Estresse Fisiológico , Animais , Fezes/química , Feminino , Hormônios/análise , Masculino , Dinâmica Populacional , Gravidez , Estações do Ano
19.
Ambio ; 44(3): 239-48, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25155194

RESUMO

Carl Linnaeus' work on the 'economy of nature' was a major early development in what became the modern field of ecology. This analysis suggests that a key subject of this work that has been ignored or misunderstood for 250 years is the rural livelihoods, especially swidden (or slash-and-burn) agriculture, which Linnaeus studied during his expeditions through rural Sweden. Rereading his reports in the light of modern work on swiddens, political ecology, and the history of science affords a new appreciation of Linnaeus' insights into traditional systems of resource exploitation. The logic of nutrient cycling in swidden agriculture and its utilization of natural dynamics to serve human ends exemplify the principles of the 'economy of nature', and gave Linnaeus a philosophical basis for understanding and defending this system of agriculture as well as other rural resource use systems in Sweden. This analysis sheds new light on Linnaeus' ethnographic work, his view of folk environmental knowledge, and his often derided identification with Sweden's ethnic peoples.


Assuntos
Agricultura/história , Conservação dos Recursos Naturais , Ecossistema , Criação de Animais Domésticos , Animais , Antropologia Cultural , História do Século XVIII , Rena , Suécia
20.
Conserv Biol ; 27(6): 1313-23, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23869724

RESUMO

The commonly expressed goal of biodiversity offsets is to achieve no net loss of specific biological features affected by development. However, strict equivalency requirements may complicate trading of offset credits, increase costs due to restricted offset placement options, and force offset activities to focus on features that may not represent regional conservation priorities. Using the oil sands industry of Alberta, Canada, as a case study, we evaluated the economic and ecological performance of alternative offset systems targeting either ecologically equivalent areas (vegetation types) or regional conservation priorities (caribou and the Dry Mixedwood natural subregion). Exchanging dissimilar biodiversity elements requires assessment via a generalized metric; we used an empirically derived index of biodiversity intactness to link offsets with losses incurred by development. We considered 2 offset activities: land protection, with costs estimated as the net present value of profits of petroleum and timber resources to be paid as compensation to resource tenure holders, and restoration of anthropogenic footprint, with costs estimated from existing restoration projects. We used the spatial optimization tool MARXAN to develop hypothetical offset networks that met either the equivalent-vegetation or conservation-priority targets. Networks that required offsetting equivalent vegetation cost 2-17 times more than priority-focused networks. This finding calls into question the prudence of equivalency-based systems, particularly in relatively undeveloped jurisdictions, where conservation focuses on limiting and directing future losses. Priority-focused offsets may offer benefits to industry and environmental stakeholders by allowing for lower-cost conservation of valued ecological features and may invite discussion on what land-use trade-offs are acceptable when trading biodiversity via offsets. Resultados Económicos y Ecológicos de Sistemas de Compensación de Biodiversidad Flexible Habib et al.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Alberta , Animais , Simulação por Computador , Mineração , Rena/fisiologia , Software , Árvores
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