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1.
We identify autoecological traits of bird species that influence the accuracy of predictive models of species distribution based on census data obtained from stratified sampling. These models would serve as a complementary approach to the development of regional bird atlases. We model the winter bird abundance of 64 terrestrial bird species in 77 census plots in Central Spain (Madrid province), using regression tree analyses. The predicted distribution of species density derived from statistical models (birds/10 ha) was compared with the published relative abundances depicted by a very accurate regional atlas of wintering birds (birds observed per 10 h). Statistical models explained an average of 41.7% of the original deviance observed in the local bird distribution (range 19.6–79.3%). Significant associations between observed relative abundances (atlas data) and predicted average densities in 1×1 km squares within 10×10 km UTMs were attained for 44 out of 64 species. Interspecific discrepancies between predicted and observed distribution maps decreased with between-year constancy in regional bird distribution and the degree of ecological specialization of species. Therefore, statistical modeling using census localities allowed us to depict geographical variations in bird abundance that were similar to those in the quantitative atlas maps. Nevertheless, bird distributions derived from statistical models are less reproducible in some species than in others, depending on their autoecological traits.  相似文献   

2.
We evaluated the diversity, social, and economic aspects of nontimber forest product (NTFP) collection in the Nilgiri Biosphere Reserve (NBR), in southern India. The NBR is a region known for its floral andfaunal diversity, as well as an area with increasing human pressure. Fifty to 75% of the households (HH) in rural areas gather a diversity of forest products. Dominant NTFPs contributed 25–60% of the average annual per capita household income from NTFPs. The mean annual per capita household income from NTFPs ranges between Rs. 134 and Rs. 4955. The mean annual income per hectare ranges from Rs. 93 in the montane zone to Rs. 3780 in the moist deciduous. NTFPs contribute 15–50% of the annual per capita income of rural households. Ethnicity plays an important role in the collection of NTFPs and ethnic tribes derive a large proportion of their annual per capita income from NTFPs.  相似文献   

3.
In studies of wild animals, one frequently encounters both census and mark-recapture-recovery data. We show how a state-space model for census data in combination with the usual multinomial-based models for ring-recovery data provide estimates of productivity not available from either type of data alone. The approach is illustrated on two British bird species. For the lapwing, we calibrate how its recent decline could be due to a decrease in productivity. For the heron, there is no evidence for a decline in productivity, and the combined analysis increases significantly the strength of logistic regressions of survival on winter severity.  相似文献   

4.
长株潭地区生态可持续性   总被引:7,自引:0,他引:7  
戴亚南  贺新光 《生态学报》2013,33(2):595-602
基于长株潭地区被批准为“全国资源节约型和环境友好型社会建设综合配套改革试验区”的背景,针对生态足迹方法的产量因子参数进行改进,利用区域产量因子代替全球产量因子,对长株潭地区1986-2005年生态足迹和生态承载力进行核算,在此基础上,着重采用两种预测方法对该地区2007-2015年生态足迹和生态容量进行预测.两种预测方法分别是二项式曲线预测模型和灰色GM(1,1)模型,对长株潭地区1986-2005年20a的人均生态足迹与时间关系进行了拟合,得出二项式曲线预测模型具有更高的预测精度;用两种预测模型预测了长株潭地区的人均生态容量,GM(1,1)模型的预测精度更高.选取精度最高的模型分别预测研究区未来10a人均生态足迹和生态容量.未来10a人均生态容量增长平缓(年平均增长率1.8%),人均生态足迹增长快(年平均增长率达16%),相应的人均生态赤字增长快.  相似文献   

5.
何威风  阎建忠  周洪  李秀彬 《生态学报》2016,36(5):1369-1379
农户薪柴消费变化对室内空气质量、农村生态环境建设影响重大,论文构建了山区农户薪柴消费的理论模型,以重庆市典型区1015份农户调查数据为例,运用Tobit模型分析了农户人均薪柴消费量的影响因素。研究表明:农户家庭能源消费中,商品能源和新能源的比重逐步增大,但薪柴依旧是农户普遍使用的能源类型,且消费量占总能源消费量的比重高;通过降低农业劳动力比重和提高非农工资水平两种途径,非农就业能显著降低农户人均薪柴消费量;家庭电器数量增多、其他收入(政府补贴、亲戚帮扶等)增加、及替代能源(液化气、沼气、煤炭等)可获得性增强也能显著降低农户人均薪柴消费量,而户主年龄大、人均牲畜数量多及房屋离集市距离远的农户家庭的人均薪柴消费量高。提出了加快薪柴替代的措施。  相似文献   

6.
食品源氮消费是人居环境养分流动的重要环节,中国食品源氮消费产生的环境排放受城乡二元结构影响在时空变化上呈现显著分异。基于物质流分析方法,从中国城乡食品消费后产物不同处理过程及其对氮代谢的影响出发,模拟氮物质代谢过程,构建了一套氮素环境排放计算模型,借以研究中国近20年来城乡食品源氮消费环境排放趋势变化及其差异。研究结果发现1993—2012年间,我国城乡居民人均食品源氮排变化轨迹迥异。同时,城乡食品源氮消费在其所造成的水体、土壤、大气环境负荷中扮演的角色各不相同:在水体环境负荷中,农村水体氮排占据主导地位,但城乡间差异正逐步缩小;在土壤环境负荷中,城市土壤氮排主导优势明显;2010年以前全国食品源氮消费大气环境负荷主要受农村气体氮排的影响,而2010年以后,城市大气氮排成为影响全国大气氮负荷的主导因素。引入社会经济因素分析后发现,城镇居民人均可支配收入水平对城镇居民人均食品源氮排起显著促进作用;而农村食品价格指数对农村居民人均食品源环境氮排呈显著抑制作用。通过情景预测分析发现:随着我国城镇化进程的加快,未来全国居民人均食品源氮排将以更快速度继续增长。  相似文献   

7.
Building stock constitutes a huge repository of construction materials in a city and a potential source for replacing primary resources in the future. This article describes the application of a methodological approach for analyzing the material stock (MS) in buildings and its spatial distribution at a city‐wide scale. A young Latin‐American city, the city of Chiclayo in Peru, was analyzed by combining geographical information systems (GIS) data, census information, and data collected from different sources. Application of the methodology yielded specific indicators for the physical size of buildings (i.e., gross floor area and number of stories) and their material composition. The overall MS in buildings, in 2007, was estimated at 24.4 million tonnes (Mt), or 47 tonnes per capita. This mass is primarily composed of mineral materials (97.7%), mainly concrete (14.1 Mt), while organic materials (e.g., 0.15 Mt of wood) and metals (e.g., 0.40 Mt of steel) constitute the remaining share (2.3%). Moreover, historical census data and projections were used to evaluate the changes in the MS from 1981 to 2017; showing a 360% increase of the MS in the last 36 years. This study provides essential supporting information for urban planners, helping to provide a better understanding of the availability of resources in the city and its future potential supply for recycling as well as to develop strategies for the management of construction and demolition waste.  相似文献   

8.
Blood lactate has been used to determine the aerobic capacity and long distance performance. Recently, a new methodology has been suggested to supplant the invasive blood lactate techniques. Salivary lactate has received attention because it shows high correlation to blood lactate in progressive overload test. We evaluated the correlation between salivary and blood lactate during a long distance run and assessed possible changes in salivary lactate concentration. Fifteen expert marathon racers ran 30 km as fast as possible. Saliva and 25 muL of blood were collected at rest and at each 6 km for lactate determination. Blood lactate concentration increased in the 6th km and then remained constant until the end of the race. Salivary lactate increased after 18 km in relation to basal. We found high correlations between blood and saliva absolute lactate (r=0.772, p<0.05) and the blood lactate relative concentration corrected by protein (r=0.718, p<0.05). The highest correlation found between absolute and relative salivary lactate was r=0.994 (p<0.001). Our results show that it is possible to use salivary lactate with absolute values or relative protein concentration. In addition, salivary lactate showed a high correlation with blood lactate in endurance events.  相似文献   

9.
In a case control study we evaluated the effects of socioeconomic and some other factors on the risk of Rheumatic Fever (RF) occurrence. We compared 148 patients, with RF first attack, with 444 controls individually matched to the patients for age, sex, and place of residence. The unemployment of parents was found to be the most closely related to RF, the estimated relative risk (RR) being 10.37 (95 per cent confidence limits 5.31 to 20.24). Among other socioeconomic factors, the following were found to be significantly related to RF: low education of mother, the RR being 2.58 (CL 1.38 to 4.83), change of place of residence during last 5 years, the RR being 5.00 (CL 1.52 to 7.93) and poor living conditions, that is, deteriorated condition of dwellings, the RR being 1.83 (CL 1.12 to 2.98), home dampness, with the RR of 2.48 (CL 1.34 to 4.61) and home crowding expressed as more then 2 persons per room, the RR being 1.72 (CL 1.08 to 2.72), less then 5 m2 of living space per capita, with the RR of 2.83 (CL 1.19 to 6.71) and sleeping in bed with other person, giving the RR of 1.65 (CL 1.02 to 2.66). Out of other factors observed, that were the subject matter of the study, history of frequent sore throat and family history positive on RF were found to be significantly more frequent in patients then in their controls, with corresponding RR of 2.01 (CL 1.41 to 2.89) and 2.81 (CL 1.68 to 4.69) respectively.  相似文献   

10.
Capture-recapture studies are frequently used to monitor the status and trends of wildlife populations. Detection histories from individual animals are used to estimate probability of detection and abundance or density. The accuracy of abundance and density estimates depends on the ability to model factors affecting detection probability. Non-spatial capture-recapture models have recently evolved into spatial capture-recapture models that directly include the effect of distances between an animal’s home range centre and trap locations on detection probability. Most studies comparing non-spatial and spatial capture-recapture biases focussed on single year models and no studies have compared the accuracy of demographic parameter estimates from open population models. We applied open population non-spatial and spatial capture-recapture models to three years of grizzly bear DNA-based data from Banff National Park and simulated data sets. The two models produced similar estimates of grizzly bear apparent survival, per capita recruitment, and population growth rates but the spatial capture-recapture models had better fit. Simulations showed that spatial capture-recapture models produced more accurate parameter estimates with better credible interval coverage than non-spatial capture-recapture models. Non-spatial capture-recapture models produced negatively biased estimates of apparent survival and positively biased estimates of per capita recruitment. The spatial capture-recapture grizzly bear population growth rates and 95% highest posterior density averaged across the three years were 0.925 (0.786–1.071) for females, 0.844 (0.703–0.975) for males, and 0.882 (0.779–0.981) for females and males combined. The non-spatial capture-recapture population growth rates were 0.894 (0.758–1.024) for females, 0.825 (0.700–0.948) for males, and 0.863 (0.771–0.957) for both sexes. The combination of low densities, low reproductive rates, and predominantly negative population growth rates suggest that Banff National Park’s population of grizzly bears requires continued conservation-oriented management actions.  相似文献   

11.
Marine birds and mammals move between various habitats during the day as they engage in behaviors related to resting, sleeping, preening, feeding, and breeding. The per capita rates of movement between these habitats, and hence the habitat occupancy dynamics, often are functions of environmental variables such as tide height, solar elevation, wind speed, and temperature. If the system recovers rapidly after disturbance, differential equation models of occupancy dynamics can be reduced to algebraic equations on two time scales. Identification of environmental factors that influence movement between habitats requires time series census data collected in both the absence and presence of disturbance.  相似文献   

12.
Projections of climate change impacts on coral reefs produced at the coarse resolution (~1°) of Global Climate Models (GCMs) have informed debate but have not helped target local management actions. Here, projections of the onset of annual coral bleaching conditions in the Caribbean under Representative Concentration Pathway (RCP) 8.5 are produced using an ensemble of 33 Coupled Model Intercomparison Project phase‐5 models and via dynamical and statistical downscaling. A high‐resolution (~11 km) regional ocean model (MOM4.1) is used for the dynamical downscaling. For statistical downscaling, sea surface temperature (SST) means and annual cycles in all the GCMs are replaced with observed data from the ~4‐km NOAA Pathfinder SST dataset. Spatial patterns in all three projections are broadly similar; the average year for the onset of annual severe bleaching is 2040–2043 for all projections. However, downscaled projections show many locations where the onset of annual severe bleaching (ASB) varies 10 or more years within a single GCM grid cell. Managers in locations where this applies (e.g., Florida, Turks and Caicos, Puerto Rico, and the Dominican Republic, among others) can identify locations that represent relative albeit temporary refugia. Both downscaled projections are different for the Bahamas compared to the GCM projections. The dynamically downscaled projections suggest an earlier onset of ASB linked to projected changes in regional currents, a feature not resolved in GCMs. This result demonstrates the value of dynamical downscaling for this application and means statistically downscaled projections have to be interpreted with caution. However, aside from west of Andros Island, the projections for the two types of downscaling are mostly aligned; projected onset of ASB is within ±10 years for 72% of the reef locations.  相似文献   

13.
The magnitude of a population's per capita death rate depends on the maximum age at death and the intensity or schedule of mortality of its members. Knowing the maximum possible lifespan that an animal can achieve when raised under defined conditions makes it possible to calculate the component of per capita death rate due to longevity alone. This component is most important to slow-growing populations of animals with relatively short lifespans. Life-table experiments with two rotifer species and a cladoceran indicate that the short lifespans of these animals account for moderate proportions (up to 37.2%) of their population death rates. Decomposing per capita death rates into two components, one due to maximum length of life and another due to differential mortality of animals of different ages, may therefore be a useful way to examine how deleterious processes, such as predation and starvation, limit growth of zooplankton populations.  相似文献   

14.
We studied intestinal absorption of vitamin E in rats with experimental renal failure (RF) and in sham-operated normal and pair-fed controls using in vivo perfusion and in vitro everted sacs. The in vivo absorption rates per unit of intestine length were significantly reduced in RF and pair-fed groups. Expression of data per unit of intestine weight gave normal values in the pair-fed but depressed values in the RF animals. Vitamin E uptake in vitro was significantly increased in RF animals, suggesting enhanced permeability. We conclude: (i) vitamin E absorption in vivo is impaired in experimental RF; (ii) this is in part due to reduced nutrient intake; and (iii) disparity between in vivo and in vitro results suggests the presence of some inhibitory influence(s) in intact animals with RF.  相似文献   

15.
This research establishes a residential indirect carbon emissions model through input–output structure decomposition analysis (IO-SDA) and LMDI, analyses the influencing factors affecting urban and rural residential carbon emissions indicators in Beijing through input–output tables from 2000 to 2010, and calculates the direct carbon emissions from residential consumption. As the results suggest, the total carbon emissions from residential consumption in Beijing showed volatility. Growing rural and urban differences in direct emissions, and for indirect emissions, mean that urban greatly exceeds rural in this regard. Rising per capita GDP and population, as well as intermediate demand and sectoral emissions intensity change induce growth in indirect emissions in both urban and rural settings: of which, per capita GDP contributes the most. Declining energy intensity contributes the most to emission reductions, followed by residential consumption rates, the rural to urban consumption ratio and consumption structure effects are much smaller.  相似文献   

16.
In order to investigate the association between mean inbreeding coefficient (α) and healthy life expectancy at birth (HALE; years) the present ecological study on 63 countries was done. Statistical analysis showed that HALE negatively and positively correlated with log(10)α and log(10)GNI per capita, respectively (p<0.001). It should be noted that log(10)α and log(10)GNI per capita were significantly correlated with each other (p<0.001). After controlling for log(10)GNI per capita, significant negative correlations between log(10)α and HALE were observed. The countries were stratified according to their GNI per capita into low- and high-income countries. In countries with high income, after controlling for log(10)GNI per capita, the correlation between HALE at birth and log(10)α was significant (for males r=-0.399, df=32, p=0.001; for females r=-0.683, df=32, p<0.001). In high-income Asian and African countries, where consanguineous marriage is common, after controlling for log(10)GNI per capita, the correlation between HALE at birth and log(10)α was significant (for males r=-0.819, df=8, p=0.004; for females r=-0.936, df=8, p<0.001). It seems that consanguinity influences HALE independent of country income.  相似文献   

17.
Realistic, individual-based models based on detailed census data are increasingly used to study disease transmission. Whether the rich structure of such models improves predictions is debated. This is studied here for the spread of varicella, a childhood disease, in a realistic population of children where infection occurs in the household, at school, or in the community at large. A methodology is first presented for simulating households with births and aging. Transmission probabilities were fitted for schools and community, which reproduced the overall cumulative incidence of varicella over the age range of 0-11 years old.Moreover, the individual-based model structure allowed us to reproduce several observed features of VZV epidemiology which were not included as hypotheses in the model: the age at varicella in first-born children was older than in other children, in accordance with observation; the same was true for children residing in rural areas. Model predicted incidence was comparable to observed incidence over time. These results show that models based on detailed census data on a small scale provide valid small scale prediction. By simulating several scenarios, we evaluate how varicella epidemiology is shaped by policies, such as age at first school enrolment, and school eviction. This supports the use of such models for investigating outcomes of public health measures.  相似文献   

18.
Recent studies suggest that species distribution models (SDMs) based on fine‐scale climate data may provide markedly different estimates of climate‐change impacts than coarse‐scale models. However, these studies disagree in their conclusions of how scale influences projected species distributions. In rugged terrain, coarse‐scale climate grids may not capture topographically controlled climate variation at the scale that constitutes microhabitat or refugia for some species. Although finer scale data are therefore considered to better reflect climatic conditions experienced by species, there have been few formal analyses of how modeled distributions differ with scale. We modeled distributions for 52 plant species endemic to the California Floristic Province of different life forms and range sizes under recent and future climate across a 2000‐fold range of spatial scales (0.008–16 km2). We produced unique current and future climate datasets by separately downscaling 4 km climate models to three finer resolutions based on 800, 270, and 90 m digital elevation models and deriving bioclimatic predictors from them. As climate‐data resolution became coarser, SDMs predicted larger habitat area with diminishing spatial congruence between fine‐ and coarse‐scale predictions. These trends were most pronounced at the coarsest resolutions and depended on climate scenario and species' range size. On average, SDMs projected onto 4 km climate data predicted 42% more stable habitat (the amount of spatial overlap between predicted current and future climatically suitable habitat) compared with 800 m data. We found only modest agreement between areas predicted to be stable by 90 m models generalized to 4 km grids compared with areas classified as stable based on 4 km models, suggesting that some climate refugia captured at finer scales may be missed using coarser scale data. These differences in projected locations of habitat change may have more serious implications than net habitat area when predictive maps form the basis of conservation decision making.  相似文献   

19.
Taking parity as the main analytic variable, the objective of this study is to investigate whether the patterns of response to national census questions in Brazil differ when Indigenous and non-Indigenous women are compared, taking into consideration whether the information was provided by the women directly or by a proxy respondent (another household member or a non-resident). We use data on children ever born to Indigenous and non-Indigenous women from two Brazilian regions, the Northeast and the North. Data on the number of household members, total household rooms, interviewee’s color/race, educational attainment, age, parity, and type of respondent were obtained from the 2010 Brazilian census. The relation between color/race and reported parity, as well as the impact of the type of respondent on this association were assessed with the Zero-inflated Negative Binomial regression, stratified by region (North and Northeast) and urban/rural status. Just over half of census interviewees answered directly the census questions (51.2% in the North and 54.4% in the Northeast). Indigenous women in the North region had the highest percentage of interviews carried out with a non-resident (12.7% total; 15.0% and 3.0% in rural and urban areas, respectively). Regardless of color/race, parity means were considerably higher when the question was answered by the woman directly (93.5%-101.4% and 15.6%-21.7% higher, compared co-resident and non-resident based answers, respectively). Parity underreporting was particularly strong in Indigenous women living in the rural North (16.0% less in comparison to White women). Proxy respondents tend to underestimate the count of children, particularly among Indigenous women from the North. The implementation of certain methodological alternatives in the Brazilian national censuses, such as the selection and training of census takers to work specifically in Indigenous territories, might be a productive means to improve data collection.  相似文献   

20.
Contemporary cycles for copper and zinc are coanalyzed with the tools of exploratory data analysis. One-year analyses (circa 1994) are performed at three discrete spatial levels-country (52 countries that comprise essentially all anthropogenic stocks and flows of the two metals), eight world regions, and the planet as a whole-and are completed both in absolute magnitude and in per capita terms. This work constitutes, to our knowledge, the first multiscale, multilevel analysis of anthropogenic resources throughout their life cycles. The results demonstrate that (1) A high degree of correlation exists between country-level copper and country-level zinc rates of fabrication and manufacturing, entry into use, net addition to in-use stocks, discard, and landfilling; (2) Regional-level rates for copper and zinc cycle parameters show the same correlations as exist at country level; (3) On a per capita basis, countries add to in-use stock almost 50% more copper than zinc; (4) The predominant discard streams for copper and zinc at the global level are different for the two metals, and relative rates of different loss processes differ geographically, so that resource recovery policies must be designed from metalspecific and location-specific perspectives; (5)When absolute magnitudes of life-cycle flows are considered, the standard deviations of the data sets decrease from country level to regional level for both copper and zinc, which is not the case for the per capita data sets, where the statistical properties of the data sets for both metals approach being independent of spatial level, thus providing a basis for predicting unmeasured per capita metal flow behavior.  相似文献   

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