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1.
Non‐Timber Forest Products like palm fruits are fundamental in the livelihood of Amerindian groups. For the last 10 years the fruits of wild palm species, like Euterpe precatoria and Mauritia flexuosa, have been entering into global markets. These species are mostly harvested felling the adults, a practice that may have a disproportionate impact in the conservation of the populations. We studied the demography of E. precatoria and M. flexuosa, two important palms of the Amazon, using integral projection models, to characterize the population dynamics and project impact of different fruit harvest methods: adult felling and direct fruit harvest. We followed over 1400 individuals from populations with low harvest intensities in the Tikuna community of Amacayacu, Amazonas, Colombia from 2011 to 2013, establishing four plots for E. precatoria in seasonally inundated forests and two for M. flexuosa in swamps. The population growth in E. precatoria was slightly declining, whereas M. flexuosa was stable. As expected, the simulations of adult felling diminished λ and the number of available adults under any scenario for either species. On the contrary, the simulations support existing information that climbing and other non‐destructive harvest methods would probably allow a sustainable management, satisfying the demand and preserving wild populations.  相似文献   

2.
The ungurahua palm (Oenocarpus bataua subsp.bataua) is widely used throughout the Amazon Basin for its thatch, fibers, wood, and edible fruits. The fruits of this species are especially important to indigenous peoples and yield a high quality oil. This study examines the use of this species by the Siona people of the Ecuadorian Amazon in the Cuyabeno Faunistic Reserve. The reproductive phenology, fruit production, and relationship between vegetative characteristics and fruit production is explored here. Fruit production varies greatly from palm to palm with a range of approximately 500–7000 fruits biennially. This amounts to approximately 700 kg/ha every two years. Height, diameter breast height (dbh), and number of leaves on an individual are poor predictors of tree productivity. Reproductive histories of individual palms are examined. The economic potential of this species and the implications of overharvesting are discussed.  相似文献   

3.
K Ottewell  E Grey  F Castillo  J Karubian 《Heredity》2012,109(6):332-339
Pollen dispersal shapes the local genetic structure of plant populations and determines the opportunity for local selection and genetic drift, but has been well studied in few animal-pollinated plants in tropical rainforests. Here, we characterise pollen movement for an insect-pollinated Neotropical canopy palm, Oenocarpus bataua, and relate these data to adult mating system and population genetic structure. The study covers a 130-ha parcel in which all adult trees (n=185) were mapped and genotyped at 12 microsatellite loci, allowing us to positively identify the source tree for 90% of pollination events (n=287 of 318 events). Mating system analysis showed O. bataua was effectively outcrossed (tm=1.02) with little biparental inbreeding (tmts=−0.005) and an average of 5.4 effective pollen donors (Nep) per female. Dispersal distances were relatively large for an insect-pollinated species (mean=303 m, max=1263 m), and far exceeded nearest-neighbour distances. Dispersal kernel modelling indicated a thin-tailed Weibull distribution offered the best fit to the genetic data, which contrasts with the fat-tailed kernels typically reported for pollen dispersal in trees. Preliminary analyses suggest that our findings may be explained, at least in part, by a relatively diffuse spatial and temporal distribution of flowering trees. Comparison with previously reported estimates of seed movement for O. bataua suggests that pollen and seed dispersal distances may be similar. These findings add to the growing body of information on dispersal in insect-pollinated trees, but underscore the need for continued research on tropical systems in general, and palms in particular.  相似文献   

4.
We used palm knowledge to understand the interaction between people and the rainforests and the factors that influence this dynamic process. We interviewed 278 informants in 12 villages in the Pastaza and Madidi areas of the western Amazon basin. Together they used 38 different palm species for 38 different uses in six use-categories (food, construction, utensils, ritual, medicine, commercial). Euterpe precatoria, Iriartea deltoidea, and Oenocarpus bataua were best known and were mentioned as useful by 76–72% of the informants in the 12 villages. There was a great variation in number of uses and in how widespread the uses were and five of the 38 useful palms were mentioned by only one informant. Among the socioeconomic factors analyzed, the residence village influenced the informants’ knowledge of palms and their uses more than any other factor. Length of education, prosperity and for how long the informant had lived in the village were also positively correlated to how many palms and palm uses were known. Gender differences in informants’ knowledge of palm uses were not observed in our data. We suggest, that the high importance of forest products to the livelihood of the villagers, the great variation in the knowledge they possess, and the fact that the differences between villages is so great, are important elements to consider when developing management plans for the sustainable use of the rainforest resources in the western Amazon.  相似文献   

5.
We report the isolation of 23 microsatellite loci obtained from a (GA)n‐enriched genomic library of Oenocarpus bataua var. bataua. The average number of alleles per locus, the mean observed and expected heterozygosities for these microsatellite loci revealed a high level of variability. The transferability of the developed markers to other Oenocarpus species and other genera within the Euterpeae tribe was high, except for the Hyospathe genus.  相似文献   

6.
Andean orogenesis has driven the development of very high plant diversity in the Neotropics through its impact on landscape evolution and climate. The analysis of the intraspecific patterns of genetic structure in plants would permit inferring the effects of Andean uplift on the evolution and diversification of Neotropical flora. In this study, using microsatellite markers and Bayesian clustering analyses, we report the presence of four genetic clusters for the palm Oenocarpus bataua var. bataua which are located within four biogeographic regions in northwestern South America: (a) Chocó rain forest, (b) Amotape‐Huancabamba Zone, (c) northwestern Amazonian rain forest, and (d) southwestern Amazonian rain forest. We hypothesize that these clusters developed following three genetic diversification events mainly promoted by Andean orogenic events. Additionally, the distinct current climate dynamics among northwestern and southwestern Amazonia may maintain the genetic diversification detected in the western Amazon basin. Genetic exchange was identified between the clusters, including across the Andes region, discarding the possibility of any cluster to diversify as a distinct intraspecific variety. We identified a hot spot of genetic diversity in the northern Peruvian Amazon around the locality of Iquitos. We also detected a decrease in diversity with distance from this area in westward and southward direction within the Amazon basin and the eastern Andean foothills. Additionally, we confirmed the existence and divergence of O. bataua var. bataua from var. oligocarpus in northern South America, possibly expanding the distributional range of the latter variety beyond eastern Venezuela, to the central and eastern Andean cordilleras of Colombia. Based on our results, we suggest that Andean orogenesis is the main driver of genetic structuring and diversification in O. bataua within northwestern South America.  相似文献   

7.
A review of palm remains recorded at archaeological sites throughout the New World is presented. Remains have been found at 130 sites from the southern United States to southern Uruguay. They are of four kinds: carbonized or dry endocarps or seeds, phytoliths, pollen, and implements. Twenty-nine genera and at least 50 species of palms (i.e., about 9% of all American species) have been recorded. The oldest record dates back to 14,700b.p. for carbonized endocarp fragments of an unidentified palm in Rondônia, Brazil. The use of palms, as recorded from remains, was particularly widespread after 9000b.p. The predominant remains are endocarps ofAcrocomia, Attalea s.l.,Astrocaryum, Bactris, Syagrus, Elaeis, andOenocarpus, all of which are important sources of edible oils or edible fruits and are still widely used by aboriginal peoples. The review supports the hypothesis that human groups have played an important role in the dispersal of some palm species in the neotropics. Humanaided dispersal ofAcrocomia aculeata from South America into Central America, and ofOenocarpus bataua from northwestern Amazonia to other areas, is postulated. Archaeological remains support the hypothesis that pejibaye (Bactris gasipaes) was domesticated in the inter-Andean valleys or on the adjacent Pacific lowlands of Colombia and later introduced into the Amazon Basin.  相似文献   

8.
We used destructive sampling to assess 14C-calibrated age and growth of five individuals of Oenocarpus bataua from 7.35 to 21.6 m of total height. The largest individual was 59-year-old. Age decreased from the collar to the top of the aboveground stem and was positively correlated with number of leaf-scars and height.  相似文献   

9.
The plant-to-plant movement of insects in one of the factors determining the distribution of individuals in insect populations. In this report the movement of barley aphids was analyzed by a statistical model. The model is represented as the convolution of three probability functions:
  1. The probability that s individuals are found on a plant at time t0:Q(s);
  2. The probability that i individuals leave the plant and remain on the ground from time t0 to t1:sCipiqs−i and p+q=1, where p and q are the proportions of individuals which do not leave a plant and which leave it once or more, respectively;
  3. The probability that j individuals climb a plant between time t0 to t1 and stay there at time t1:e−λλj!, where λ is the mean of the individuals.
The probability that l individuals are located on a plant at time t1 is represented by the following equation It was shown by simple experiments that the experimental populations were well fitted to the model.  相似文献   

10.
Amazonian forest plots are used to quantify biodiversity and carbon sequestration, and provide the foundation for much of what is known about tropical ecology. Many plots are assumed to be undisturbed, but recent work suggests that past fire, forest openings, and cultivation created vegetation changes that have persisted for decades to centuries (ecological legacies). The Yasuní Forest Dynamics plot is one of the most biodiverse places on earth, yet its human history remains unknown. Here, we use charcoal and phytolith analysis to investigate the fire and vegetation history of the Yasuní forest plot, and compare results with nearby forest plots in Colombia (Amacayacu) and Peru (Medio Putumayo-Algodón [MPA]) to explore the spatial variability of past disturbances and ecological legacies in northwestern Amazonia. Three 14C dated charcoal fragments provided evidence for a modern (1956 CE) and a past fire event ca. 750 years ago at Yasuní, compared with fire ages of 1000–1600 years ago documented at Amacayacu and MPA. Small-scale disturbances and localized canopy openings also occurred in the Yasuní plot. Phytolith assemblages from Yasuní and Amacayacu showed more variability in past vegetation change than MPA. Low-intensity, non-continuous disturbances occurred at all three plots in the past, and our results highlight the variability of past human activities both in space and time in northwestern Amazonia. Our data also suggest that post-Columbian human disturbances from the Rubber Boom (AD 1850–1920) and subsequent oil exploration have likely left stronger ecological legacies than those left by pre-Columbian peoples in our studied regions.  相似文献   

11.
We reviewed information on management of useful palms in South America. We documented management for 96 species, from incidental activities intended to increase populations of wild palms to the inclusion of palms in complex agroforestry systems. Two species, Bactris gasipaes and Parajubaea cocoides, are domesticated. Managed species are remarkably fewer than species used in the region, which suggests that harvesters often disregard the fate of the species they use. The best way of managing palms is to employ harvest methods that do not decimate the populations. Although a variety of harvesting techniques have been documented, overharvest is common, and mismanagement prevails – unnecessary felling of palms in order to harvest leaves or fruits is a widespread practice. Research should focus on assessing production in response to management practices, but eradicating the habit of destructive harvest is an obvious priority. Research on palm management must be combined with actions addressed to all stakeholders of the palm/humans system.  相似文献   

12.
Understanding the relative effects of the many factors that may influence recruitment of ungulates is fundamental to managing their populations. Over the last 4 decades, average recruitment in some populations of elk (Cervus elaphus) in Oregon, USA declined from >50 to <20 juveniles per 100 females, and several competing hypotheses address these declines. We developed a priori models and constructed covariates spanning 1977–2005 from hunter-killed elk, elk population estimates, cougar harvest, and weather statistics to evaluate abiotic, bottom-up, and top-down factors that may explain annual variation and long-term trends of pregnancy, juveniles-at-heel in late autumn, and recruitment of juvenile elk in spring. In models of pregnancy status, August precipitation, age, and cougar index had positive effects, whereas previous year (t − 1) winter severity or winter precipitation(t−1) and elk density had negative effects. In models of juvenile-at-heel in late autumn, August precipitation, August precipitation(t−1), cougar index × elk density(t−1), and age had positive effects, whereas cougar index, elk density(t−1), and winter precipitation(t−1) had negative effects. Juvenile recruitment was best explained by positive effects of August precipitation(t−1), lactation rate, and cougar index × elk density(t−1) and negative effects of cougar index and elk density(t−1). Winter severity, precipitation, and temperature were not significant in explaining variation in elk recruitment. Annual variation in pregnancy, juvenile-at-heel, and recruitment was most influenced by August precipitation, whereas long-term trends in recruitment were most influenced by cougar densities with relatively weak effects of elk density. These results provide insight into causes of year-to-year and long-term trends of elk recruitment and provide a basis for more rigorous evaluation of factors affecting recruitment of elk. © 2012 The Wildlife Society.  相似文献   

13.
The spear leaves of the palms Astrocaryum chambira and A. standleyanum have been traditionally used by Colombian indigenous communities as a source of fiber for handicraft production. Traditional management practices, including destructive harvest, have reduced population sizes of both species. We monitored a population of A. chambira in the Amazon, and one of A. standleyanum at the Pacific lowlands of Colombia. We then constructed integral projection models (IPM) to evaluate the transient population dynamics of populations under different exploitation regimes. Our results show that during the next 50 years the population of A. standleyanum will grow at an annual rate of 2.0 percent, and that of A. chambira at a rate of 0.8 percent. However, projected population growth is highly sensitive to harvest in both species: a destructive harvest of 5 percent of all usable individuals (subadults and adults) would cease population growth, while a 10 percent harvest intensity would cause populations to decrease by 0.5–0.6 percent annually. Our simulations further indicate that management practices associated with indigenous slash‐and‐burn agriculture would reduce fiber production, whereas caring for seedlings would increase population growth and fiber production in the coming decades. In order to sustain viable populations of both species and maintain a steady fiber supply, it is vital to prevent destructive harvest practices, and to leave some forest areas untouched, where populations can regenerate and act as a source of seedlings for intervened areas.  相似文献   

14.
The productivity of the final larval and adult populations of a large sized diplopod, Japonaria laminata armigera were studied at a warm temperate ever-green broad leaf forest in Chiba Japan. The population density was about 200/m2 in May 1962, and 7/m2 in May 1966, the former being about 30 times as much as the latter. A remarkable growth of animals was seen from June to November, and the growth pattern of individuals in both populations was very similar. The growth and mortality were calculated by the following formulae, where G is growth, M mortality, Nt number at the time t,Wt−1 mean body weight of animals at the time t−1, ΔN decrease in number during the period of time from t−1 to t, ΔW growth in mean body weight during the time from t−1 to t. The constant b in the formula R=aWb representing the relation between body weight and oxygen consumption of Japonaria laminata was determined at 0.81, and Q10 was estimated at about 2. The amounts of growth and assimilation were calculated. The pattern of dynamics in terms of productivity of the population in the two periods were very similar. But, the amounts of assimilation were computed at 57.8 kcal/m2/from May 1962 to April 1963, and 3.01 kcal from May 1966 to April 1967. The former is 20 times as much as the latter. The growth or ecological efficiencies for the populations were similar.  相似文献   

15.
《农业工程》2019,39(6):451-455
In order to harvest potential yield of eggplant and to find a suitable sowing time and phosphorus level for eggplant, an experiment was conducted at Ornamental Nursery, Department of Horticulture, The University of Agriculture Peshawar in February 2013. The experiment was laid out in randomized complete block (RCB) design with split plot arrangements. There were two factors i.e. Phosphorus levels and dates of Sowing. Phosphorus levels were assigned to the main plot while sowing dates were kept in the subplot. The data on Number of branches plant−1, Days to flowering, Days to fruiting, Number of fruits plant−1 and Yield Plot−1were significantly affected by phosphorus level and date of sowing. While the data on plant height was not significant, and overall results showed that early sowing date (February 25) produced significantly good results as compared to the rest of the sowing dates. Moreover, phosphorus level was also significantly affected the experimental parameters. Phosphorus level (70 kg ha−1) produced significantly best results in all the parameters followed by Phosphorus level (100 kg ha−1) in almost all the parameters. Thus it is concluded that early sowing of bringel (eggplants) is recommended with phosphorus level (70 & 100 kg ha−1).  相似文献   

16.
Autotrophic respiration involves the use of fixed carbon by plants for their own metabolism, resulting in the release of carbon dioxide as a by‐product. Little is known of how autotrophic respiration components vary across environmental gradients, particularly in tropical ecosystems. Here, we present stem CO2 efflux data measured across an elevation transect spanning ca. 2800 m in the Peruvian Amazon and Andes. Forest plots from five elevations were studied: 194, 210, 1000, 1500, and 3025 m asl Stem CO2 efflux (Rs) values from each plot were extrapolated to the 1‐ha plot level. Mean Rs per unit stem surface area declined significantly with elevation, from 1.14±0.12 at 210 m elevation to 0.62±0.09 μmol C m−2 s−1 at 3025 m elevation. When adjusted for changing forest structure with elevation, this is equivalent to 6.45±1.12 Mg C ha−1 yr−1 at 210 m elevation to 2.94±0.19 Mg C ha−1 yr−1 at 3025 m elevation. We attempted to partition stem respiration into growth and maintenance respiration components for each site. Both growth and maintenance respiration rates per unit stem showed similar, moderately significant absolute declines with elevation, but the proportional decline in growth respiration rates was much greater. Stem area index (SAI) showed little trend along the transect, with declining tree stature at higher elevations being offset by an increased number of small trees. This trend in SAI is sensitive to changes in forest stature or size structure. In the context of rapid regional warming over the 21st century, such indirect, ecosystem‐level temperature responses are likely to be as important as the direct effects of temperature on maintenance respiration rates.  相似文献   

17.
A clone of Synechococcus isolated from Lake Huron and natural populations of Synechococcus from lakes Huron and Michigan were studied in 1989 to examine the diel division cycle and to provide estimates of the in situ growth rate based on the frequency of dividing cells (FDC) method. Cultured populations of Synechococcus exhibited a consistent diel division pattern with a midday/afternoon (1100–1800 h) peak in the percent of dividing cells. The maximum percent of dividing cells varied among cultures (8-27%) and was related to the growth rate. A small fraction of dividing cells (3-5%) remained throughout the dark period, suggesting that some cells were arrested in the doublet stage prior to division. The duration of division (td) ranged from 2.6-4.9 h, with a 3.7 h mean for cultures with growth rates ≥0.34 d−1 but increased to 8 h at a lower growth rate of 0.20 d−1. The diel division pattern for natural populations was very similar to the laboratory clone; an afternoon peak (1400-2100 h) in dividing cells and a small fraction of dividing cells (2-5%) remained during the dark period. The maximum percent of dividing cells for natural populations ranged from 6-10%. In situ growth rates, determined from the FDC and assuming a constant td of 3.7 h, ranged from 0.30-0.42 d−1. The FDC method may provide accurate estimates of in situ growth, particularly in environments where the growth rate is >0.34 d−1, but in lakes Huron and Michigan where growth rates can be lower and td values may increase, FDC-growth rates must be viewed with caution.  相似文献   

18.
Forest harvesting and wildfire were widespread in the upper Great Lakes region of North America during the early 20th century. We examined how long this legacy of disturbance constrains forest carbon (C) storage rates by quantifying C pools and fluxes after harvest and fire in a mixed deciduous forest chronosequence in northern lower Michigan, USA. Study plots ranged in age from 6 to 68 years and were created following experimental clear‐cut harvesting and fire disturbance. Annual C storage was estimated biometrically from measurements of wood, leaf, fine root, and woody debris mass, mass losses to herbivory, soil C content, and soil respiration. Maximum annual C storage in stands that were disturbed by harvest and fire twice was 26% less than a reference stand receiving the same disturbance only once. The mechanism for this reduction in annual C storage was a long‐lasting decrease in site quality that endured over the 62‐year timeframe examined. However, during regrowth the harvested and burned forest rapidly became a net C sink, storing 0.53 Mg C ha−1 yr−1 after 6 years. Maximum net ecosystem production (1.35 Mg C ha−1 yr−1) and annual C increment (0.95 Mg C ha−1 yr−1) were recorded in the 24‐ and 50‐year‐old stands, respectively. Net primary production averaged 5.19 Mg C ha−1 yr−1 in experimental stands, increasing by < 10% from 6 to 50 years. Soil heterotrophic respiration was more variable across stand ages, ranging from 3.85 Mg C ha−1 yr−1 in the 6‐year‐old stand to 4.56 Mg C ha−1 yr−1 in the 68‐year‐old stand. These results suggest that harvesting and fire disturbances broadly distributed across the region decades ago caused changes in site quality and successional status that continue to limit forest C storage rates.  相似文献   

19.
Current agricultural realities dictate that crops be developed which can be grown with fewer petroleum inputs and on marginal croplands. A palm tree native to the Amazon Valley,Jessenia bataua, found in both swamplands and upland forests has been studied. The fruits of this tree have long been exploited by indigenous peoples as a source of oil and a milk-like drink. Chemical analyses of the oil show it to be similar to olive oil. Chemical and biological assays of the mesocarp pulp protein reveal its quality to be comparable to that of good animal protein and considerably better than most grain and legume proteins. Rats fed diets containingJessenia bataua mesocarp oil and pulp showed normal weight gains when compared to those fed diets with similar quanities of corn oil and casein.Jessenia bataua is an example of a little-known wild plant that could provide a new source of food protein and oil for combating world hunger.  相似文献   

20.
Frugivorous animals frequently generate clumped distributions of seeds away from source trees, but genetic consequences of this phenomenon remain poorly resolved. Seed dispersal of the palm Oenocarpus bataua by long-wattled umbrellabirds Cephalopterus penduliger generates high seed densities in leks (i.e., multi-male display sites), providing a suitable venue to investigate how dispersal by this frugivore may influence seed source diversity and genetic structure at local and landscape levels. We found moderate levels of maternal seed source diversity in primary seed rain across five leks in northwest Ecuador (unweighted mean alpha diversity α = 9.52, weighted mean αr = 3.52), with considerable variation among leks (αr range: 1.81–24.55). Qualitatively similar findings were obtained for allelic diversity and heterozygosity. Higher densities of O. bataua adults around leks were associated with higher values of αr and heterozygosity (non-significant trends) and allelic diversity (significant correlation). Seed source overlap between different leks was not common but did occur at low frequency, providing evidence for long-distance seed dispersal by umbrellabirds into leks. Our findings are consistent with the idea that seed pool diversity within leks may be shaped by the interaction between density of local trees, which can vary considerably between leks, and umbrellabird foraging ecology, particularly a lack of territorial defense of fruiting trees. Taken as a whole, this work adds to our growing appreciation of the ways resource distribution and associated frugivore foraging behaviors mechanistically shape seed dispersal outcomes and the distribution of plant genotypes across the landscape.  相似文献   

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