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Sample records for mamey pouteria sapota

  1. Characterization of Mamey Sapote (Pouteria sapota [Jacq.] H.E. Moore & Stearn.) germplasm at the USDA-ARS Tropical Agriculture Research Station

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mamey sapote (Pouteria sapota [Jacq.] H.E. Moore & Stearn) is a tropical tree fruit in the Sapotaceae, which is native to Central America and southern Mexico. The tree is used for timber and shade; however it is the sweet, nutrient and vitamin rich fruit that is eaten out of hand, in milkshakes...

  2. Isolation of β-Cryptoxanthin-epoxides, Precursors of Cryptocapsin and 3'-Deoxycapsanthin, from Red Mamey (Pouteria sapota).

    PubMed

    Turcsi, Erika; Murillo, Enrique; Kurtán, Tibor; Szappanos, Ádám; Illyés, Tünde-Zita; Gulyás-Fekete, Gergely; Agócs, Attila; Avar, Péter; Deli, József

    2015-07-01

    From an extract of red mamey (Pouteria sapota) β-cryptoxanthin-5,6-epoxide, β-cryptoxanthin-5',6'-epoxide, 3'-deoxycapsanthin, and cryptocapsin were isolated and characterized by UV-vis spectroscopy, electronic circular dichroism (ECD), nuclear magnetic resonance (NMR) spectroscopy, and mass spectrometry (MS). Epoxidation of β-cryptoxanthin delivered the β-(5'R,6'S)- and (5'S,6'R)-cryptoxanthin-5',6'-epoxides, which were identified by HPLC-ECD analysis. These carotenoids among others are quite common in the fruits of Central America, and as they are natural provitamins A, they should play an important role in the diet of the mostly vitamin A deficient population of this region. PMID:26057604

  3. Deposition Form and Bioaccessibility of Keto-carotenoids from Mamey Sapote (Pouteria sapota), Red Bell Pepper (Capsicum annuum), and Sockeye Salmon (Oncorhynchus nerka) Filet.

    PubMed

    Chacón-Ordóñez, Tania; Esquivel, Patricia; Jiménez, Víctor M; Carle, Reinhold; Schweiggert, Ralf M

    2016-03-01

    The ultrastructure and carotenoid-bearing structures of mamey sapote (Pouteria sapota) chromoplasts were elucidated using light and transmission electron microscopy and compared to carotenoid deposition forms in red bell pepper (Capsicum annuum) and sockeye salmon (Oncorhynchus nerka). Globular-tubular chromoplasts of sapote contained numerous lipid globules and tubules embodying unique provitamin A keto-carotenoids in a lipid-dissolved and presumably liquid-crystalline form, respectively. Bioaccessibility of sapotexanthin and cryptocapsin was compared to that of structurally related keto-carotenoids from red bell pepper and salmon. Capsanthin from bell pepper was the most bioaccessible pigment, followed by sapotexanthin and cryptocapsin esters from mamey sapote. In contrast, astaxanthin from salmon was the least bioaccessible keto-carotenoid. Thermal treatment and fat addition consistently enhanced bioaccessibility, except for astaxanthin from naturally lipid-rich salmon, which remained unaffected. Although the provitamin A keto-carotenoids from sapote were highly bioaccessible, their qualitative and quantitative in vivo bioavailability and their conversion to vitamin A remains to be confirmed. PMID:26888016

  4. Molecular markers developed for Pouteria sapota

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The tropical plant Pouteria sapota (Jacq.) is known for its edible fruits that contain unique carotenoids, and for the chemicals extracted from its bark, leaves and roots having fungitoxic, insecticidal, anti-inflamatory, anti-oxidant and tyrosinase inhibitory activities. We reported high throughpu...

  5. Development of a Large Set of Microsatellite Markers in Zapote Mamey (Pouteria sapota (Jacq.) H.E. Moore & Stearn) and Their Potential Use in the Study of the Species.

    PubMed

    Arias, Renée S; Martínez-Castillo, Jaime; Sobolev, Victor S; Blancarte-Jasso, Nasib H; Simpson, Sheron A; Ballard, Linda L; Duke, Mary V; Liu, Xiaofen F; Irish, Brian M; Scheffler, Brian E

    2015-01-01

    Pouteria sapota is known for its edible fruits that contain unique carotenoids, as well as for its fungitoxic, anti-inflammatory and anti-oxidant activity. However, its genetics is mostly unknown, including aspects about its genetic diversity and domestication process. We did high-throughput sequencing of microsatellite-enriched libraries of P. sapota, generated 5223 contig DNA sequences, 1.8 Mbp, developed 368 microsatellites markers and tested them on 29 individuals from 10 populations (seven wild, three cultivated) from Mexico, its putative domestication center. Gene ontology BLAST analysis of the DNA sequences containing microsatellites showed potential association to physiological functions. Genetic diversity was slightly higher in cultivated than in the wild gene pool (HE = 0.41 and HE = 0.35, respectively), although modified Garza-Williamson Index and Bottleneck software showed evidence for a reduction in genetic diversity for the cultivated one. Neighbor Joining, 3D Principal Coordinates Analysis and assignment tests grouped most individuals according to their geographic origin but no clear separation was observed between wild or cultivated gene pools due to, perhaps, the existence of several admixed populations. The developed microsatellites have a great potential in genetic population and domestication studies of P. sapota but additional sampling will be necessary to better understand how the domestication process has impacted the genetic diversity of this fruit crop. PMID:26111173

  6. Genetic diversity and structure in Mamey [P. sapota (Jacq.) H.E. Moore & Stearn] by using microsatellite markers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The tropical plant Pouteria sapota (Jacq.) is known for its edible fruits that contain unique carotenoids, as well as for the fungitoxic, anti-inflamatory and anti-oxidant activity of extracts from its bark, leaves and roots, though its genetics is unknown. We did high-throughput sequencing of micr...

  7. Yield and fruit quality traits of mamey sapote grown at two locations in Puerto Rico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Six mamey sapote (Pouteria sapota) cultivars grown on an Oxisol and Ultisol were evaluated for four years under intensive management at Isabela and Corozal, Puerto Rico, respectively. There were significant differences in number and weight of fruit per hectare between locations and years. Signific...

  8. EFFECT OF DEFOLIATION AND ROOT-FEEDING ON MAMEY SAPOTE YIELD

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mamey sapote, Pouteria sapota (Sapotaceae), is a valuable fruit crop that grows well in Puerto Rico. Unfortunately it is a preferred host of Phyllophaga vandinei (Coleoptera: Scarabaeidae). The adults of this beetle can defoliate trees and the larvae feed on the roots, in some cases resulting in the...

  9. Development of a large set of microsatellite markers in Zapote Maney (Pouteria sapota (Jacq.) (H.E. Moore & Stearn) and their potential use in the study of the species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The tropical plant Pouteria sapota (Jacq.) is known for its edible fruits that contain unique carotenoids, and for the chemicals extracted from its bark, leaves and roots having fungitoxic, insecticidal, anti-inflamatory, anti-oxidant and tyrosinase inhibitory activities. Currently, there is no gen...

  10. Analysis of polyphenolic antioxidants from the fruits of three pouteria species by selected ion monitoring liquid chromatography-mass spectrometry.

    PubMed

    Ma, Jun; Yang, Hui; Basile, Margaret J; Kennelly, Edward J

    2004-09-22

    Pouteria campechiana, Pouteria sapota, and Pouteria viridis are tropical plants in the Sapotaceae family that bear edible fruits. The fresh fruits of these three Pouteria species were each extracted, and activity-guided fractionations were performed to identify the antioxidant constituents. Seven polyphenolic antioxidants, gallic acid (1), (+)-gallocatechin (2), (+)-catechin (3), (-)-epicatechin (4), dihydromyricetin (5), (+)-catechin-3-O-gallate (6), and myricitrin (7), were isolated and identified. Extracts of the three Pouteria fruits were analyzed by a selected ion monitoring liquid chromatography-mass spectrometry method to quantify their polyphenolic antioxidants. The highest level of the seven measured polyphenols was found in P. sapota, the second highest in P. viridis, and the lowest in P. campechiana. The levels of the seven polyphenols corresponded with the results of the 1,1-diphenyl-2-picrylhydrazyl assay, by which P. sapota had the highest antioxidant activity, P. viridis the second highest, and P. campechiana the lowest. PMID:15366835

  11. Yield and Fruit Quality Traits of Mamey Sapote Cultivars Grown at two Locations in Puerto Rico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The demand for tropical fruits has increased significantly during the last decade as consumers seek healthy and more diverse food products. There is a lack of formal experimentation to determine yield performance and fruit quality traits of mamey sapote cultivars. Six mamey sapote cultivars (Copan...

  12. Acute Toxicity and Dermal and Eye Irritation of the Aqueous and Hydroalcoholic Extracts of the Seeds of “Zapote” Pouteria mammosa (L.) Cronquist

    PubMed Central

    Dutok, Carlos M. S.; Berenguer-Rivas, Clara Azalea; Rodríguez-Leblanch, Elizabeth; Pérez-Jackson, Liliana; Chil-Nuñez, Idelsy; Escalona-Arranz, Julio César; Reyes-Tur, Bernardo; Queiroz, Margareth M. C.

    2015-01-01

    The common use of Pouteria mammosa (L.) Cronquist, “Mamey or Zapote,” in food and ethnobotanic medicine shows its low or absent toxicity as fruit extracts prepared from seeds. However, it is essential to conduct security trials to scientifically support their use in drug therapy. This study evaluated the aqueous and hydroalcoholic extract (25%) Acute Oral Toxicity, obtained from the seeds of P. mammosa, in Sprague Dawley rats and dermal and eye irritability in New Zealand rabbits. The 404 and 405 acute dermal and eye irritation/corrosion guidelines were used, as well as the 423 Acute Oral Toxicity guideline, Acute Toxic Class Method of the Organization for Economic Cooperation and Development (OECD). The aqueous extract was located in the following category: not classified as toxic (CTA 5), while hydroalcoholic extract at 25% was classified as dangerous (CTA 4). Both extracts can be used without side reaction that irritates the skin which permitted classification as potentially not irritant. P. mammosa in the two extracts caused mild and reversible eye irritation, and it was classified as slightly irritating. PMID:26273696

  13. Acute Toxicity and Dermal and Eye Irritation of the Aqueous and Hydroalcoholic Extracts of the Seeds of "Zapote" Pouteria mammosa (L.) Cronquist.

    PubMed

    Dutok, Carlos M S; Berenguer-Rivas, Clara Azalea; Rodríguez-Leblanch, Elizabeth; Pérez-Jackson, Liliana; Chil-Nuñez, Idelsy; Escalona-Arranz, Julio César; Reyes-Tur, Bernardo; Queiroz, Margareth M C

    2015-01-01

    The common use of Pouteria mammosa (L.) Cronquist, "Mamey or Zapote," in food and ethnobotanic medicine shows its low or absent toxicity as fruit extracts prepared from seeds. However, it is essential to conduct security trials to scientifically support their use in drug therapy. This study evaluated the aqueous and hydroalcoholic extract (25%) Acute Oral Toxicity, obtained from the seeds of P. mammosa, in Sprague Dawley rats and dermal and eye irritability in New Zealand rabbits. The 404 and 405 acute dermal and eye irritation/corrosion guidelines were used, as well as the 423 Acute Oral Toxicity guideline, Acute Toxic Class Method of the Organization for Economic Cooperation and Development (OECD). The aqueous extract was located in the following category: not classified as toxic (CTA 5), while hydroalcoholic extract at 25% was classified as dangerous (CTA 4). Both extracts can be used without side reaction that irritates the skin which permitted classification as potentially not irritant. P. mammosa in the two extracts caused mild and reversible eye irritation, and it was classified as slightly irritating. PMID:26273696

  14. Acute toxicity of seeds of the sapodilla (Achras sapota L.).

    PubMed

    Singh, P D; Simon, W R; West, M E

    1984-01-01

    An aqueous extract of the sapodilla seed (Achras sapota L.) was acutely toxic to mice and rats (i.p. LD50 = 190 and 250 mg/kg, respectively) with symptoms of dyspnoea, apnoea and convulsions. Soxhlet extraction and chromatographic separation of the seed constituents yielded a brown amorphous solid containing saponin. This was heat-stable and toxic by the i.p. route (LD50 = 30-50 mg/kg) but non-toxic by the oral route in mice and rats. It is proposed that the toxicity of the sapodilla seed is due mainly to the saponin content. PMID:6719472

  15. Sapodilla plum (Achras sapota) induces apoptosis in cancer cell lines and inhibits tumor progression in mice.

    PubMed

    Srivastava, Mrinal; Hegde, Mahesh; Chiruvella, Kishore K; Koroth, Jinsha; Bhattacharya, Souvari; Choudhary, Bibha; Raghavan, Sathees C

    2014-01-01

    Intake of fruits rich in antioxidants in daily diet is suggested to be cancer preventive. Sapota is a tropical fruit grown and consumed extensively in several countries including India and Mexico. Here we show that methanolic extracts of Sapota fruit (MESF) induces cytotoxicity in a dose-dependent manner in cancer cell lines. Cell cycle analysis suggested activation of apoptosis, without arresting cell cycle progression. Annexin V-propidium iodide double-staining demonstrated that Sapota fruit extracts potentiate apoptosis rather than necrosis in cancer cells. Loss of mitochondrial membrane potential, upregulation of proapoptotic proteins, activation of MCL-1, PARP-1, and Caspase 9 suggest that MESF treatment leads to activation of mitochondrial pathway of apoptosis. More importantly, we show that MESF treatment leads to significant inhibition of tumor growth and a 3-fold increase in the life span of tumor bearing animals compared to untreated tumor mice. PMID:25142835

  16. Sapodilla Plum (Achras sapota) Induces Apoptosis in Cancer Cell Lines and Inhibits Tumor Progression in Mice

    PubMed Central

    Srivastava, Mrinal; Hegde, Mahesh; Chiruvella, Kishore K.; Koroth, Jinsha; Bhattacharya, Souvari; Choudhary, Bibha; Raghavan, Sathees C.

    2014-01-01

    Intake of fruits rich in antioxidants in daily diet is suggested to be cancer preventive. Sapota is a tropical fruit grown and consumed extensively in several countries including India and Mexico. Here we show that methanolic extracts of Sapota fruit (MESF) induces cytotoxicity in a dose-dependent manner in cancer cell lines. Cell cycle analysis suggested activation of apoptosis, without arresting cell cycle progression. Annexin V-propidium iodide double-staining demonstrated that Sapota fruit extracts potentiate apoptosis rather than necrosis in cancer cells. Loss of mitochondrial membrane potential, upregulation of proapoptotic proteins, activation of MCL-1, PARP-1, and Caspase 9 suggest that MESF treatment leads to activation of mitochondrial pathway of apoptosis. More importantly, we show that MESF treatment leads to significant inhibition of tumor growth and a 3-fold increase in the life span of tumor bearing animals compared to untreated tumor mice. PMID:25142835

  17. Wound-healing properties of nut oil from Pouteria lucuma

    PubMed Central

    Rojo, Leonel E; Villano, Caren M; Joseph, Gili; Schmidt, Barbara; Shulaev, Vladimir; Shuman, Joel L; Lila, Mary Ann; Raskin, Ilya

    2014-01-01

    Summary Background Cell migration, angiogenesis, inflammation, and extracellular matrix remodeling are key events in wound healing. Natural products, including fatty acids (FAs), can accelerate wound healing by modulating the aforementioned events. Aims This study aims to evaluate the effect of lucuma (Pouteria lucuma O Kezte) nut oil (LNO) on fibroblasts migration, angiogenesis, inflammation, bacterial and fungal growth, and wound healing. Methods GC–MS analysis of FAs methyl esters (FAMES) was used for chemical characterization of LNO. In vitro studies were carried out with LNO investigating the induction of cell migration, cytoskeleton remodeling of human fibroblasts, inhibition of LPS-induced nitric oxide production in macrophages, and antibacterial and antifungal effects. Two in vivo studies were carried out to study LNO’s effect on angiogenesis and wound healing: (i) tail fin regeneration in transgenic zebrafish larvae expressing enhanced green fluorescent protein (EGFP) in vascular endothelial cells was used to study vessel sprouting and wound healing and (ii) the closure of wounds was evaluated in CD-1 mice after topical applications of LNO-containing formulations. Results Lucuma nut oil is a mixture of FAs, 99.7% of which were characterized. Major components of LNO (w/w) are linoleic acid (38.9%), oleic acid (27.9%), palmitic acid (18.6%), stearic acid (8.9%), and γ linolenic acid (2.9%). In vitro studies showed that LNO significantly promoted migration and vinculin expression in human fibroblasts. LNO decreased LPS-induced nitric oxide production and did not display significant antibacterial or antifungal effects. LNO induced tail fin regeneration in transgenic zebrafish larvae 48 h after tail fin amputation and significantly accelerated cutaneous wound closure in CD-1 mice. Conclusions Natural FAs from P. lucuma nut promote skin regeneration and, thus, may have applications in medicine and skin care. PMID:20883291

  18. Response of different maturity stages of sapota (Manilkara achras Mill.) cv. Kallipatti to in-package ethylene absorbent.

    PubMed

    Bhutia, Wangdup; Pal, R K; Sen, Sangita; Jha, S K

    2011-12-01

    Sapota fruits are highly perishable due to their climacteric nature. The rapid softening of fruits is primarily due to high activity of many oxidative enzymes and liberation of ethylene. Harvest maturity plays a crucial role in deciding the marketability of climacteric fruits in general. Attempt has been made to evaluate the response of ethylene absorbent on variable maturity groups of harvested Sapota cv. Kallipatti with the objective to delay the ripening during transit and extend its marketability during storage at ambient condition (27-32 °C & 65-75% R.H.). Harvested fruits having three different degree of ripeness (as maturity indices viz. mature, half-ripe and ripe) were packed with or without ethylene absorbent sachets (Bioconservación, France) in 10 kg CFB boxes and transported from Dahnu to Delhi covering a distant of approximately 2500 KM by truck on road along with conventional packaging as control. The fruits were evaluated immediately on arrival at Delhi and subsequently during storage for various physical, physiological, biochemical and decay parameters. Mature fruits with ethylene absorbent exhibited maximum delay in ripening, low ethylene liberation, weight loss and high fruit firmness. The response of ethylene absorbent to extend the marketability of ripe fruit was not significant. PMID:23572819

  19. Weathering processes in the Rio Icacos and Rio Mameyes watersheds in Eastern Puerto Rico: Chapter I in Water quality and landscape processes of four watersheds in eastern Puerto Rico

    USGS Publications Warehouse

    Buss, Heather L.; White, Arthur F.

    2012-01-01

    Streams draining watersheds of the two dominant lithologies (quartz diorite and volcaniclastic rock) in the Luquillo Experimental Forest of eastern Puerto Rico have very high fluxes of bedrock weathering products. The Río Blanco quartz diorite in the Icacos watershed and the Fajardo volcaniclastic rocks in the Mameyes watershed have some of the fastest documented rates of chemical weathering of siliceous rocks in the world. Rapid weathering produces thick, highly leached saprolites in both watersheds that lie just below the soil and largely isolate subsurface biogeochemical and hydrologic processes from those in the soil. The quartz diorite bedrock in the Icacos watershed weathers spheroidally, leaving large, relatively unweathered corestones that are enveloped by slightly weathered rock layers called rindlets. The rindlets wrap around the corestones like an onionskin. Within the corestones, biotite oxidation is thought to induce the spheroidal fracturing that leads to development of rindlets; plagioclase in the rindlets dissolves, creating additional pore spaces. Near the rindlet-saprolite interface, the remaining plagioclase dissolves, hornblende dissolves to completion, and precipitation of kaolinite, gibbsite, and goethite becomes pervasive. In the saprolite, biotite weathers to kaolinite and quartz begins to dissolve. In the soil layer, both quartz and kaolinite dissolve. The volcaniclastic bedrock of the Mameyes watershed weathers even faster than the quartz diorite bedrock of the Icacos watershed, leaving thicker saprolites that are devoid of all primary minerals except quartz. The quartz content of volcaniclastic bedrock may help to control watershed geomorphology; high-quartz rocks form thick saprolites that blanket ridges. Hydrologic flow paths within the weathering profiles vary with total fluid flux, and they influence the chemistry of streams. Under low-flow conditions, the Río Icacos and its tributaries are fed by rainfall and by groundwater from

  20. Flavonoid Detection in Hydroethanolic Extract of Pouteria torta (Sapotaceae) Leaves by HPLC-DAD and the Determination of Its Mutagenic Activity

    PubMed Central

    Costa, Daryne L.M.G.; Rinaldo, Daniel; Varanda, Eliana A.; de Sousa, Juliana F.; Nasser, Ana L.M.; Silva, Ana C.Z.; Baldoqui, Débora C.; Vilegas, Wagner

    2014-01-01

    Abstract It is well known that phytotherapy has grown in popularity in recent years. Because a drug cannot be administered without ensuring its effectiveness and safety, the standardization and regulation of phytotherapeutic drugs are required by the global market and governmental authorities. This article describes a simple and reliable high-performance liquid chromatography–diode array detection analysis method for the simultaneous detection of myricetin-3-O-β-D-galactopyranoside, myricetin-3-O-α-L-arabinopyranoside, and myricetin-3-O-α-L-rhaminopyranoside present in the hydroethanolic extract (ethanol/H2O, 7:3, v/v) of Pouteria torta. The mutagenic activity of the extract was evaluated on Salmonella typhimurium and by an in vivo micronucleus test on the peripheral blood cells of Swiss mice. The linearity, sensitivity, selectivity, repeatability, accuracy, and precision of the assay were evaluated. The analytical curves were linear and exhibited good repeatability (with a deviation of less than 5%) and demonstrated good recovery (within the 83–107% range). The results demonstrate that the hydroethanolic extract exhibited a mutagenic activity in both assays, suggesting caution in the use of this plant in folk medicine. PMID:25055245

  1. Characterization of main primary and secondary metabolites and in vitro antioxidant and antihyperglycemic properties in the mesocarp of three biotypes of Pouteria lucuma.

    PubMed

    Fuentealba, Claudia; Gálvez, Lena; Cobos, Ariel; Olaeta, José Antonio; Defilippi, Bruno G; Chirinos, Rosana; Campos, David; Pedreschi, Romina

    2016-01-01

    Pouteria lucuma is an Andean fruit from pre-Incas' times highly appreciated due to its characteristic flavor and taste in its homeland. We characterized the primary (e.g., sugars and organic acids), and secondary (e.g., phenolics and carotenoids) and in vitro antioxidant and antihyperglycemic properties of Rosalia, Montero and Leiva 1 lucuma biotypes. Significant differences were found in these metabolites and functional properties related to biotype and ripeness stage. Results showed significant amounts of sugars (119.4-344 mg total sugars g(-1)DW) and organic acids (44.4-30.0 mg g(-1)DW) and functional associated compounds such as ascorbic acid (0.35-1.07 mg g(-1)DW), total phenolics (0.7-61.6 mg GAE g(-1)DW) and total carotenoids (0.22-0.50 mg β-carotene g(-1)DW). Important in vitro antioxidant and antihyperglycemic properties were found and provide the base for the standardization of lucuma harvest and postharvest focused not only on the enhancement of sensory but functional properties. PMID:26212989

  2. A SURVEY OF ROOT-FEEDING PESTS ON TROPICAL FRUIT TREES IN PUERTO RICO

    Technology Transfer Automated Retrieval System (TEKTRAN)

    From March 2003 to December 2005 traps were used to monitor the abundance of Diaprepes abbreviatus and Phyllophaga spp. adults emerging from the soil at the base of several exotic tropical fruit trees (Pouteria sapota, Manilkara zapota, Litchi chinensis, and Nephelium lappaceum) at three different s...

  3. [Fruit flies (Diptera: Tephritidae) and their parasitoids (Hymenoptera: Braconidae) associated to host plants in the southern region of Bahia State].

    PubMed

    Bittencourt, M A L; da Silva, A C M; Silva, V E S; Bomfim, Z V; Guimarães, J A; de Souza Filho, M F; Araujo, E L

    2011-01-01

    The association among Anastrepha species, braconid parasitoids and host fruits in southern Bahia is recorded. Doryctobracon areolatus (Szépligeti) was associated with A. serpentina (Wied.) in Pouteria caimito, A. bahiensis Lima in Helicostylis tomentosa, A. sororcula Zucchi in Eugenia uniflora, and A. obliqua (Macquart) in Spondias purpurea. Anatrepha obliqua was unique in fruits of Averrhoa carambola, but associated with D. areolatus, Asobara anastrephae (Muesebeck) and Utetes anastrephae (Viereck). In Achras sapota, A. serpentina was associated with A. anastrephae and D. areolatus, while in Psidium guajava, A. fraterculus (Wied.) and A. sororcula were associated with D. areolatus and U. anastrephae. PMID:21710038

  4. Interactions between terrestrial mammals and the fruits of two neotropical rainforest tree species

    NASA Astrophysics Data System (ADS)

    Camargo-Sanabria, Angela A.; Mendoza, Eduardo

    2016-05-01

    Mammalian frugivory is a distinctive biotic interaction of tropical forests; however, most efforts in the Neotropics have focused on cases of animals foraging in the forest canopy, in particular primates and bats. In contrast much less is known about this interaction when it involves fruits deposited on the forest floor and terrestrial mammals. We conducted a camera-trapping survey to analyze the characteristics of the mammalian ensembles visiting fruits of Licania platypus and Pouteria sapota deposited on the forest floor in a well preserved tropical rainforest of Mexico. Both tree species produce large fruits but contrast in their population densities and fruit chemical composition. In particular, we expected that more species of terrestrial mammals would consume P. sapota fruits due to its higher pulp:seed ratio, lower availability and greater carbohydrate content. We monitored fruits at the base of 13 trees (P. sapota, n = 4 and L. platypus, n = 9) using camera-traps. We recorded 13 mammal species from which we had evidence of 8 consuming or removing fruits. These eight species accounted for 70% of the species of mammalian frugivores active in the forest floor of our study area. The ensemble of frugivores associated with L. platypus (6 spp.) was a subset of that associated with P. sapota (8 spp). Large body-sized species such as Tapirus bairdii, Pecari tajacu and Cuniculus paca were the mammals more frequently interacting with fruits of the focal species. Our results further our understanding of the characteristics of the interaction between terrestrial mammalian frugivores and large-sized fruits, helping to gain a more balanced view of its importance across different tropical forests and providing a baseline to compare against defaunated forests.

  5. SPATIAL DISTRIBUTION OF PHYLLOPHAGA VANDINEI (COLEOPTERA: SCARABAEIDAE)EMERGENCE WITHIN AND AROUND A MAMEY SAPOTE ORCHARD

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A method of accurately monitoring Phyllophaga vandinei, an important pest of fruit trees in Puerto Rico, is urgently needed. Cone emergence cages have been used, but it has been unclear how effective they are. This study demonstrates that deployment and placement of the traps has a great impact on t...

  6. Medicinal plants used for dogs in Trinidad and Tobago.

    PubMed

    Lans, C; Harper, T; Georges, K; Bridgewater, E

    2000-06-12

    This paper documents ethnoveterinary medicines used to treat dogs in Trinidad and Tobago. In 1995, a 4-stage process was used to conduct the research and document the ethnoveterinary practices. Twenty-eight ethnoveterinary respondents were identified using the school-essay method, which is a modified rapid rural appraisal (RRA) technique. Semi-structured interviews were held with these respondents as well as with 30 veterinarians, 27 extension officers and 19 animal-health assistants and/or agricultural officers, and the seven key respondents that they identified. The final step involved hosting four participatory workshops with 55 of the respondents interviewed to discuss the ethnoveterinary data generated from the interviews and to determine dosages for some of the plants mentioned. Supplementary interviews were conducted in 1997 and 1998. Seeds of Carica papaya, and leaves of Cassia alata, Azadirachta indica, Gossypium spp., Cajanus cajan and Chenopodium ambrosiodes are used as anthelmintics. The anthelmintics Gossypium spp. and Chenopodium ambrosiodes are the most frequently used species. Crescentia cujete pulp, Musa spp. stem exudate, the inside of the pods of Bixa orellana, leaves of Cordia curassavica and Eclipta alba plant tops are used for skin diseases. Musa spp. stem exudate, seeds of Manilkara zapota, Pouteria sapota and Mammea americana and leaves of Cordia curassavica, Scoparia dulcis and Nicotiana tabacum are used to control ectoparasites. Dogs are groomed with the leaves of Cordia curassavica, Bambusa vulgaris and Scoparia dulcis. Psidium guajava buds and leaves and the bark of Anacardium occidentale are used for diarrhoea. Owners attempt to achieve milk let-down with a decoction of the leaves of Stachytarpheta jamaicensis. The plant uses parallel those practised in human folk medicine in other Caribbean countries and in other tropical countries. PMID:10821961

  7. Anastrepha ludens and Anastrepha serpentina (Diptera: Tephritidae) do not infest Psidium guajava (Myrtaceae), but Anastrepha obliqua occasionally shares this resource with Anastrepha striata in nature.

    PubMed

    Birke, Andrea; Aluja, Martin

    2011-08-01

    This study examined whether economically important fruit fly species Anastrepha ludens (Loew), Anastrepha serpentina (Wiedemann), and Anastrepha obliqua (Macquart) (Diptera: Tephritidae) may opportunistically exploit guavas, Psidium guajava L. (Myrtaceae), growing near preferred natural hosts. We collected 3,459 kg of guavas and 895 kg of other known host species [sour orange, Citrus aurantium L.; grapefruit, Citrus paradisi Macfadyen; mango, Mangifera indica L.; white sapote, Casimiroa edulis La Llave and Lex.; sapote, Pouteria sapota (Jacq.); sapodilla, Manilkara zapota L.; and wild plum, Spondias purpurea L. and Spondias mombin L.] along an altitudinal gradient over a 4-yr period (2006-2009). Plants were growing in sympatry in 23 localities where the guavas are usually infested in the state of Veracruz, M6xico. The guava samples yielded 20,341 Anastrepha spp. pupae in total (overall mean, 5.88 pupae per kg of fruit). Confirming previous reports, Anastrepha fraterculus (Wiedemann) and Anastrepha striata (Schiner) were found heavily infesting guavas in Veracruz. Importantly, although we did not find evidence that A. ludens and A. serpentina are able to attack this valuable commodity, we document for the first time in the agriculturally important state of Veracruz that P. guajava is an alternative natural host plant of A. obliqua. We recovered two fruit in the mango-growing locality of la Vibora, Tlalixcoyan, that harbored larvae of A. striata and A. obliqua. This finding has important practical implications for management of A. obliqua. Over the entire altitudinal gradient, when individual fruit infestation was examined, a dynamic pattern of species dominance was unveiled with guavas growing below 800 m above sea level mainly attacked by A. striata and a progressive replacement with increasing altitude by A. fraterculus. Interestingly, most individual fruit examined (97%) harbored a single species of fruit fly, a finding that may be taken as evidence of

  8. [Biological evaluation of Cuban plants VI].

    PubMed

    Jiménez Misas, C A; Rojas Hernández, N M; López Abraham, A M

    1979-01-01

    The study of the antibacterial activity of plants growing in Cuba is pursued. Aqueous, alcoholic and ketonic extracts were prepared from five species, and it was found that the best inhibitions corresponded to the species Hamelia patens, Nephrolepis acuminata, Calocarpum sapota and Colocasia antiquorum. PMID:382282

  9. 40 CFR 180.532 - Cyprodinil; tolerances for residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Register citations affecting § 180.532, see the List of CFR Sections Affected, which appears in the Finding... 1.2 Sapote, mamey 1.2 Spanish lime 2.0 Star apple 1.2 Turnip, greens 10.0 Vegetable, cucurbit,...

  10. 40 CFR 180.532 - Cyprodinil; tolerances for residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Register citations affecting § 180.532, see the List of CFR Sections Affected, which appears in the Finding... 1.2 Sapote, mamey 1.2 Spanish lime 2.0 Star apple 1.2 Turnip, greens 10.0 Vegetable, cucurbit,...

  11. 77 FR 8861 - Pesticide Products; Receipt of Applications To Register New Uses

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-15

    ... the use of special characters, any form of encryption, and be free of any defects or viruses. Docket...: Avocado, sapote, black, canistel, sapote, mamey, mango, papaya, sapodilla, star apple, bean, snap, and tea... for pesticide products containing currently registered active ingredients, pursuant to the...

  12. 75 FR 28009 - Notice of Receipt of Several Pesticide Petitions Filed for Residues of Pesticide Chemicals in or...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-19

    ... the use of special characters, any form of encryption, and be free of any defects or viruses. Docket..., papaya, star apple, black sapote, mango, sapodilla, canistel, and mamey sapote at 0.20 ppm; and tea at 15...) under 40 CFR 180.920 when used as a pesticide inert ingredient in pesticide formulations. A...

  13. Healthful and nutritional components in select Florida tropical fruits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fourteen tropical fruits from south Florida (red guava, white guava, carambola, red pitaya (red dragon), white pitaya (white dragon), mamey, sapodilla, lychee, longan, green mango, ripe mango, green papaya and ripe papaya) were evaluated for phenolic compounds, antioxidant activity, ascorbic acid (v...

  14. Placement of cone emergence cages and its impact on monitoring of Phyllophaga vandinei (Coleoptera: Scarabaeidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cone emergence cages were used to monitor the emergence of may beetles, Phyllophaga vandinei, in an orchard of mamey sapote in Isabela, P.R. More adult beetles emerged in traps placed to the west of the tree than traps placed to the east of a tree, between trees within rows or in the field adjacent ...

  15. Salt tolerances of some mainland tree species select as through nursery screening.

    PubMed

    Miah, Md Abdul Quddus

    2013-09-15

    A study of salt tolerance was carried out on germination, survival and height growth performance of important mesophytic species such as Acacia auriculiformis, Acacia hybrid, Artocarpus heterophyllus, Albizia procera, Albizia lebbeck, Acacia nilotica, Achras sapota, Casuarina equisetifolaia, Emblica officinalis, Leucaena leucocephala, Samania saman, Swetenia macrophylla, Terminalia arjuna, Tamarindus indica, Terminalia bellirica and Thespesia populnea in nursery stage using fresh water and salt (NaCl) solutions of 10, 15 and 20 ppm. Effect of salt on germination, survival performance and height growth performance were examined in this condition. Based on the observation, salt tolerance of these species has been determined Acacia auriculiformis, Acacia hybrid, Achras sapota, Casuarina equisetifolia, Leucaena leucocephala and Tamarindus indica has showed the best capacity to perform in different salinity conditions. Acacia nilotica, Emblica officinalis, Thespesia populnea has performed better. Albizia procera, Samania saman and Terminalia bellirica, germination and height performance showed good but when salinity increases survivability were decreases. PMID:24502152

  16. Inhibitory activity of α-amylase and α-glucosidase by plant extracts from the Brazilian cerrado.

    PubMed

    Souza, Paula Monteiro de; Sales, Paloma Michelle de; Simeoni, Luiz Alberto; Silva, Elton Clementino; Silveira, Dâmaris; Magalhães, Pérola de Oliveira

    2012-03-01

    Diabetes mellitus is the most common disease in the world. One therapeutic approach for treating diabetes is inhibition of α-amylase and α-glucosidase activities to reduce postprandial blood glucose levels. In vitro tests showed that several plant extracts from Brazilian cerrado species can inhibit the activity of α-amylase and α-glucosidase. The extracts of Eugenia dysenterica, Stryphnodendron adstringens, Pouteria caimito, Pouteria ramiflora, and Pouteria torta showed strong α-amylase and α-glucosidase inhibitory activity. Eugenia dysenterica, P. caimito, P. ramiflora, and P. torta aqueous extracts exerted the highest activity against α-amylase (IC₅₀) values of 14.93, 13.6, 7.08, and 5.67 µg/mL, respectively) and α-glucosidase (IC₅₀ values of 0.46, 2.58, 0.35, and 0.22 µg/mL, respectively). Stryphnodendron adstringens ethanol extract also exhibited inhibitory activity against both enzymes (IC₅₀) 1.86 µg/mL against α-amylase and 0.61 µg/mL against α-glucosidase). The results suggest that the activity of these cerrado plants on α-amylase and α-glucosidase represents a potential tool for development of new strategies for treatment of diabetes. PMID:22134849

  17. Plants from Brazilian Cerrado with Potent Tyrosinase Inhibitory Activity

    PubMed Central

    Souza, Paula Monteiro; Elias, Silvia Taveira; Simeoni, Luiz Alberto; de Paula, José Elias; Gomes, Sueli Maria; Guerra, Eliete Neves Silva; Fonseca, Yris Maria; Silva, Elton Clementino; Silveira, Dâmaris; Magalhães, Pérola Oliveira

    2012-01-01

    The increased amount of melanin leads to skin disorders such as age spots, freckles, melasma and malignant melanoma. Tyrosinase is known to be the key enzyme in melanin production. Plants and their extracts are inexpensive and rich resources of active compounds that can be utilized to inhibit tyrosinase as well as can be used for the treatment of dermatological disorders associated with melanin hyperpigmentation. Using in vitro tyrosinase inhibitory activity assay, extracts from 13 plant species from Brazilian Cerrado were evaluated. The results showed that Pouteria torta and Eugenia dysenterica extracts presented potent in vitro tyrosinase inhibition compared to positive control kojic acid. Ethanol extract of Eugenia dysenterica leaves showed significant (p<0.05) tyrosinase inhibitory activity exhibiting the IC50 value of 11.88 µg/mL, compared to kojic acid (IC50 value of 13.14 µg/mL). Pouteria torta aqueous extract leaves also showed significant inhibitory activity with IC50 value of 30.01 µg/mL. These results indicate that Pouteria torta and Eugenia dysenterica extracts and their isolated constituents are promising agents for skin-whitening or antimelanogenesis formulations. PMID:23173036

  18. Antioxidant, anti-collagenase and anti-elastase activities of Phyllanthus emblica, Manilkara zapota and silymarin: an in vitro comparative study for anti-aging applications.

    PubMed

    Pientaweeratch, Sirinya; Panapisal, Vipaporn; Tansirikongkol, Anyarporn

    2016-09-01

    Context Phyllanthus emblica L. (Euphorbiaceae) (amla), Manilkara zapota L.P. Royen (Sapotaceae) (sapota) and silymarin are reported to contain antioxidant effects. However, information on other biological activities relating to the anti-aging properties is limited. Objective To compare in vitro antioxidants, anti-collagenase (MMP-1 and MMP-2) and anti-elastase properties as well as the phenolic and flavonoid contents of amla, sapota and silymarin as potential anti-aging ingredients. Materials and methods The ethanol amla and sapota fruit extracts were prepared by three cycles of maceration with 24 h duration each. The total phenolic (TPC) and flavonoid (TFC) contents were determined. The antioxidant capacity was evaluated by DPPH and ABTS assays. The effects of MMP-1, MMP-2 and elastase inhibitions were determined by using the EnzChek® assay kits (Molecular-Probes, Eugene, OR). Results Amla exhibited the highest in TPC (362.43 ± 11.2 mg GAE/g) while silymarin showed the highest in TFC (21.04 ± 0.67 mg QE/g). Results of antioxidant activity by DPPH and ABTS methods showed that amla possessed the most potent capacity with IC50 values of 1.70 ± 0.07 and 4.45 ± 0.10 μg/mL, respectively. Highest inhibitions against MMP-1, MMP-2 and elastase were detected for sapota with IC50 values of 89.61 ± 0.96, 86.47 ± 3.04 and 35.73 ± 0.61 μg/mL, respectively. Discussion and conclusion Test extracts offered anti-aging properties in different mechanisms. Amla showed the highest phenolic content and antioxidant property with moderate anti-collagenase. Silymarin exhibited measurable flavonoid content with anti-elastase effect. Sapota showed the highest collagenase and elastase inhibitions with moderate antioxidant effect. Thus, extracts might be added as a mixture to gain the overall anti-aging effects. PMID:26912420

  19. Draft Genome Sequence of a Strictly Anaerobic Dichloromethane-Degrading Bacterium.

    PubMed

    Kleindienst, Sara; Higgins, Steven A; Tsementzi, Despina; Konstantinidis, Konstantinos T; Mack, E Erin; Löffler, Frank E

    2016-01-01

    An anaerobic, dichloromethane-degrading bacterium affiliated with novel Peptococcaceae was maintained in a microbial consortium. The organism originated from pristine freshwater sediment collected from Rio Mameyes in Luquillo, Puerto Rico, in October 2009 (latitude 18°21'43.9″, longitude -65°46'8.4″). The draft genome sequence is 2.1 Mb and has a G+C content of 43.5%. PMID:26941136

  20. 40 CFR 180.593 - Etoxazole; tolerances for residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ....5 Canistel 0.20 Cattle, fat 0.02 Cattle, liver 0.01 Corn, field, forage 0.80 Corn, field, grain 0.01....02 Goat, liver 0.01 Grape, raisin 1.5 Hop, dried cones 7.0 Horse, fat 0.02 Horse, liver 0.01 Mango 0... Sapodilla 0.20 Sapote, black 0.20 Sapote, mamey 0.20 Sheep, fat 0.02 Sheep, liver 0.01 Spearmint, oil...

  1. 40 CFR 180.364 - Glyphosate; tolerances for residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...: For Federal Register citations affecting § 180.364, see the List of CFR Sections Affected, which... 0.2 Ginger, white, flower 0.2 Gourd, buffalo, seed 0.1 Governor's plum 0.2 Gow kee, leaves 0.2 Grain... Mamey apple 0.2 Mango 0.2 Mangosteen 0.2 Marmaladebox 0.2 Mioga, flower 0.2 Noni 0.20 Nut, pine 1.0...

  2. 40 CFR 180.364 - Glyphosate; tolerances for residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... residues. Editorial Note: For Federal Register citations affecting § 180.364, see the List of CFR Sections... Galangal, roots 0.2 Ginger, white, flower 0.2 Gourd, buffalo, seed 0.1 Governor's plum 0.2 Gow kee, leaves... Longan 0.2 Lychee 0.2 Mamey apple 0.2 Mango 0.2 Mangosteen 0.2 Marmaladebox 0.2 Mioga, flower 0.2 Noni...

  3. Draft Genome Sequence of a Strictly Anaerobic Dichloromethane-Degrading Bacterium

    PubMed Central

    Higgins, Steven A.; Tsementzi, Despina; Konstantinidis, Konstantinos T.; Mack, E. Erin

    2016-01-01

    An anaerobic, dichloromethane-degrading bacterium affiliated with novel Peptococcaceae was maintained in a microbial consortium. The organism originated from pristine freshwater sediment collected from Rio Mameyes in Luquillo, Puerto Rico, in October 2009 (latitude 18°21′43.9″, longitude −65°46′8.4″). The draft genome sequence is 2.1 Mb and has a G+C content of 43.5%. PMID:26941136

  4. Total antioxidant activity and fiber content of select Florida-grown tropical fruits.

    PubMed

    Mahattanatawee, Kanjana; Manthey, John A; Luzio, Gary; Talcott, Stephen T; Goodner, Kevin; Baldwin, Elizabeth A

    2006-09-20

    Fourteen tropical fruits from south Florida (red guava, white guava, carambola, red pitaya (red dragon), white pitaya (white dragon), mamey sapote, sapodilla, lychee, longan, green mango, ripe mango, green papaya, and ripe papaya) were evaluated for antioxidant activity, total soluble phenolics (TSP), total ascorbic acid (TAA), total dietary fiber (TDF), and pectin. ORAC (oxygen radical absorbance capacity) and DPPH (1,1-diphenyl-2-picrylhydrazyl, radical scavenging activity) assays were used to determine antioxidant activity. The TSP, ORAC, and DPPH ranged from 205.4 to 2316.7 g gallic acid equiv/g puree, <0.1 to 16.7 micromol Trolox equiv/g puree, and 2.1 to 620.2 microg gallic acid equiv/g puree, respectively. The TAA, TDF, and pectin ranged from 7.5 to 188.8 mg/100 g, 0.9 to 7.2 g/100 g, and 0.20 to 1.04 g/100 g, respectively. The antioxidant activities, TSP, TAA, TDF, and pectin were influenced by cultivar (papaya, guava, and dragon fruit) and ripening stage (papaya and/or mango). Antioxidant activity showed high correlations with levels of TSP compounds (r = 0.96) but low correlations with levels of ascorbic acid (r = 0.35 and 0.23 for ORAC and DPPH data, respectively). The antioxidant activities evaluated by both ORAC and DPPH showed similar trends where red guava and carambola exhibited the highest and sapodilla and green papaya exhibited the lowest levels. Guava and mamey sapote exhibited the highest TDF and pectin levels. Many of the tropical fruits were shown to contain an abundance of hydrolyzable tannins, ellagic acid conjugates, and flavone glycosides. Preliminary descriptions are given of the phenols in red/white pitaya (dragonfruit), lychee, and mamey sapote, these fruit being thus far uncharacterized in the literature. PMID:16968105

  5. Seasonal variation and processing of vascular plant organic matter in tropical montane catchments as reflected by riverine DOC compositions

    NASA Astrophysics Data System (ADS)

    Hernes, P.; Dyda, R. Y.; McDowell, W. H.

    2015-12-01

    Tropical rivers are responsible for two thirds of global fluxes of terrigenous organic matter to the oceans, yet because of their remote locations relative to most industrialized countries, they are poorly studied compared to temperate and even Arctic rivers. This study measured lignin biomarkers on weekly samples from two Puerto Rican rivers, the Mameyes and the Rio Icacos, over the course of ~9 months in order to investigate watershed controls on organic matter export via rivers. In both rivers, carbon-normalized yields of lignin increased with discharge, indicating higher organic matter contributions from vascular plants and lower contributions from microbial sources. Lignin biomarkers can be used to distinguish between conifer and deciduous trees as well as woody and nonwoody tissues, and the source signatures of the two rivers were essentially the same, indicating similar vegetation and sources of organic materials to both rivers. Thus, differences in diagenetic lignin parameters can be attributed to differences in processing within the two watersheds. For example, the Rio Icacos is a much flashier system with much higher sediment loads during storm events, which can lead to significant exchange of organic matter between the dissolved and particulate phase. Acid to aldehyde ratios for vanillyl and syringyl lignin phenols, (Ad:Al)v and (Ad:Al)s, are commonly used indicators of degradation. Plots of (Ad:Al)s vs. (Ad:Al)v for the two rivers reveal a significantly steeper slope for the Mameyes, which could reflect differences in the mineralogy between the systems, as the Mameyes watershed is underlain by volcaniclastic materials while the Rio Icacos is underlain by granodiorite. It is a commonly held assumption that base materials and soils should exert a strong influence on riverine organic matter compositions, but paired watershed studies are comparatively rare even in temperate climates. Hence, measureable differences between the two systems studied here

  6. A capture-recapture model of amphidromous fish dispersal.

    PubMed

    Smith, W E; Kwak, T J

    2014-04-01

    Adult movement scale was quantified for two tropical Caribbean diadromous fishes, bigmouth sleeper Gobiomorus dormitor and mountain mullet Agonostomus monticola, using passive integrated transponders (PITs) and radio-telemetry. Large numbers of fishes were tagged in Río Mameyes, Puerto Rico, U.S.A., with PITs and monitored at three fixed locations over a 2·5 year period to estimate transition probabilities between upper and lower elevations and survival probabilities with a multistate Cormack-Jolly-Seber model. A sub-set of fishes were tagged with radio-transmitters and tracked at weekly intervals to estimate fine-scale dispersal. Changes in spatial and temporal distributions of tagged fishes indicated that neither G. dormitor nor A. monticola moved into the lowest, estuarine reaches of Río Mameyes during two consecutive reproductive periods, thus demonstrating that both species follow an amphidromous, rather than catadromous, migratory strategy. Further, both species were relatively sedentary, with restricted linear ranges. While substantial dispersal of these species occurs at the larval stage during recruitment to fresh water, the results indicate minimal dispersal in spawning adults. Successful conservation of diadromous fauna on tropical islands requires management at both broad basin and localized spatial scales. PMID:24673127

  7. A capture-recapture model of amphidromous fish dispersal

    USGS Publications Warehouse

    Smith, W.; Kwak, Thomas J.

    2014-01-01

    Adult movement scale was quantified for two tropical Caribbean diadromous fishes, bigmouth sleeper Gobiomorus dormitor and mountain mullet Agonostomus monticola, using passive integrated transponders (PITs) and radio-telemetry. Large numbers of fishes were tagged in Rio Mameyes, Puerto Rico, U.S.A., with PITs and monitored at three fixed locations over a 2-5 year period to estimate transition probabilities between upper and lower elevations and survival probabilities with a multistate Cormack-Jolly-Seber model. A sub-set of fishes were tagged with radio-transmitters and tracked at weekly intervals to estimate fine-scale dispersal. Changes in spatial and temporal distributions of tagged fishes indicated that neither G. dormitor nor A. monticola moved into the lowest, estuarine reaches of Rio Mameyes during two consecutive reproductive periods, thus demonstrating that both species follow an amphidromous, rather than catadromous, migratory strategy. Further, both species were relatively sedentary, with restricted linear ranges. While substantial dispersal of these species occurs at the larval stage during recruitment to fresh water, the results indicate minimal dispersal in spawning adults. Successful conservation of diadromous fauna on tropical islands requires management at both broad basin and localized spatial scales.

  8. Radiation preservation of foods of plant origin. Part VI. Mushrooms, tomatoes, minor fruits and vegetables, dried fruits, and nuts

    SciTech Connect

    Thomas, P.

    1988-01-01

    In this concluding article in the series on the technological feasibility of ionizing radiation treatment for shelf life improvement of fruits and vegetables, the present status of research on several commodities that have not been dealt with earlier is discussed. The commodities include mushrooms, tomatoes, pineapples, lychees, longans, rambutans, mangostenes, guavas, sapotas, loquats, ber, soursops, passion fruits, persimmons, figs, melons, cucumbers, aubergines, globe artichokes, endives, lettuce, ginger, carrots, beet roots, turnips, olives, dates, chestnuts, almonds, pistachios, and other dried fruits and nuts. Changes induced by irradiation on metabolism, chemical constituents, and organoleptic qualities are considered while evaluating the shelf life. The commodities have been grouped into those showing potential benefits and those not showing any clear advantages from radiation treatment. Shelf life improvement of mushrooms and insect disinfestation in dried fruits, nuts, and certain fresh fruits appears to have immediate potential for commercial application. 194 references.

  9. Guatemalan plants extracts as virucides against HIV-1 infection.

    PubMed

    Bedoya, Luis M; Alvarez, Amparo; Bermejo, Mercedes; González, Nuria; Beltrán, Manuela; Sánchez-Palomino, Sonsoles; Cruz, Sully M; Gaitán, Isabel; del Olmo, Esther; Escarcena, Ricardo; García, Pablo A; Cáceres, Armando; San Feliciano, Arturo; Alcamí, José

    2008-06-01

    Prevention methods to avoid transmission of pathogens, including HIV, are crucial in the control of infectious diseases, not only to block epidemic spread but to avoid long-term treatments leading to emergence of resistances and drug associated side effects. Together with vaccine development, the discovery of new virucidal agents represents a research priority in this setting. In the screening of new compounds with antiviral activity, three Guatemalan plant extracts from Justicia reptans, Neurolaena lobata and Pouteria viridis were evaluated with a classic antiviral assay and were found to inhibit HIV replication. This activity was corroborated by an original recombinant virus assay, leading us to perform a deeper study of the virucidal activity. Active fractions were non-toxic in vitro and also inhibited other enveloped viruses. Moreover, these fractions were able to inhibit the transfer of HIV from dendritic cells (DCs) to lymphocytes, that represents the main way of HIV spread in vivo. PMID:18068962

  10. Phenolic constituents and antioxidant capacity of four underutilized fruits from the Amazon region.

    PubMed

    Gordon, Andre; Jungfer, Elvira; da Silva, Bruno Alexandre; Maia, Jose Guilherme S; Marx, Friedhelm

    2011-07-27

    The Amazon region comprises a plethora of fruit-bearing species of which a large number are still agriculturally unimportant. Because fruit consumption has been attributed to an enhanced physical well-being, interest in the knowledge of the chemical composition of underexplored exotic fruits has increased during recent years. This paper provides a comprehensive identification of the polyphenolic constituents of four underutilized fruits from the Amazon region by HPLC/DAD-ESI-MS(n). Araçá ( Psidium guineense ), jambolão ( Syzygium cumini ), muruci ( Byrsonima crassifolia ), and cutite ( Pouteria macrophylla ) turned out to be primarily good sources of hydrolyzable tannins and/or flavonols. Additionally, different flavanonols and proanthocyanidins were identified in some fruits. The antioxidant capacity was determined by using the total oxidant scavenging capacity (TOSC) assay. Cutite showed the highest antioxidant capacity followed by jambolão, araçá, and muruci. PMID:21662239

  11. Influence of Soil Erosion and Landslide Occurrence on Soil Organic Carbon Storage and Loss in the Luquillo Critical Zone Observatory, Puerto Rico

    NASA Astrophysics Data System (ADS)

    Dialynas, Y. G.; Bastola, S.; Bras, R. L.; Marin-Spiotta, E.; Silver, W. L.; Arnone, E.; Noto, L. V.

    2015-12-01

    Tropical rainforests play a significant role in the global carbon (C) cycle. The Luquillo Critical Zone Observatory (LCZO) in Puerto Rico is characterized by intense erosion and landslide occurrence, which have been historically influenced by human activity and land use change, and drive the redistribution and burial of soil organic C (SOC) across the landscape. Estimates of regional C budgets do not systematically account for linkages between hydrological, geomorphological, and biogeochemical processes, which control the fate of eroded SOC. We quantify the impacts of erosion and rainfall-triggered landslides on SOC oxidation and accumulation at the Mameyes and Icacos watersheds. We developed and calibrated a spatially-explicit model of SOC dynamics, i.e. tRIBS-ECO (Triangulated Irregular Network-based Real-time Integrated Basin Simulator-Erosion and Carbon Oxidation), based on a coupled physically-based hydro-geomorphic model. The model inputs we used include measurements of SOC content at different horizons, and SOC oxidation and production rates derived from SOC turnover characteristics. We demonstrate the extent to which depth-dependent SOC oxidation and production are altered at eroding hillslopes and at landslide locations, and how this is being moderated by management practices. We estimated the SOC deposition rates at the floodplains of Mameyes and Icacos rivers, part of which is fluvially transported out of the system. The contrasting lithology of the two watersheds leads to different hydro-geomorphological behavior which controls the redistribution and storage of SOC. Results showed that topography and heterogeneity of tropical vegetation lead to significant spatial variability of the erosion-induced soil CO2 flux to the atmosphere. We highlight the importance of the representation of SOC redistribution driven by local variation in lithological and geomorphological characteristics and hydroclimatic conditions in attempts to quantify watershed-scale soil C

  12. Stable isotope (δ18O and δ2H) data for precipitation, stream water, and groundwater in Puerto Rico

    USGS Publications Warehouse

    Scholl, Martha A.; Torres-Sanchez, Angel; Rosario-Torres, Manuel

    2014-01-01

    Puerto Rico is located in the northeastern Caribbean Sea (18.2 °N, 66.3 °W), with the Atlantic Ocean on its northern coast. The U.S. Geological Survey’s Water, Energy, and Biogeochemical Budgets (WEBB) program study area in which most of these data were collected comprises the El Yunque National Forest and surrounding area of eastern Puerto Rico. Samples were collected in two forested watersheds, the Rio Mameyes and the Rio Icacos/Rio Blanco, on opposite sides of a ridge in the Luquillo Mountains on the eastern end of the island (fig. 1). Elevation in both watersheds ranges from sea level to approximately 1,000 meters (m). Near sea level, land use is mixed pasture, moist forest, and residential, grading to completely forested within the boundaries of El Yunque National Forest. Forest type changes with elevation from tabonuco to palo colorado to sierra palm to cloud forest above approximately 950 m (Murphy and others, 2012). The Rio Mameyes watershed is oriented north-northeast, and the basin is underlain by volcaniclastic bedrock (basaltic to andesitic volcanic sandstone/mudstone/conglomerate/breccia). The Rio Icacos/Rio Blanco watershed is oriented south-southeast. The Rio Icacos is one of the headwaters of the Rio Blanco and is underlain by quartz diorite. The lower Rio Blanco basin is underlain by andesitic volcaniclastic bedrock. This report also contains a long-term rain isotope dataset from the San Agustin site, in north-central Puerto Rico (fig. 1). Puerto Rico has a tropical climate dominated by easterly trade winds, and seasonal climate patterns affect the hydrology of the study area. The summer wet season is characterized by convective precipitation from tropical easterly waves, troughs, and cyclonic low-pressure systems, including tropical storms and hurricanes; in contrast, the drier winter season is characterized by trade-wind showers and frontal systems. The highest single-event rainfall totals tend to be associated with tropical storms

  13. Evaluation of antihyperglycemia and antihypertension potential of native Peruvian fruits using in vitro models.

    PubMed

    Pinto, Marcia Da Silva; Ranilla, Lena Galvez; Apostolidis, Emmanouil; Lajolo, Franco Maria; Genovese, Maria Inés; Shetty, Kalidas

    2009-04-01

    Local food diversity and traditional crops are essential for cost-effective management of the global epidemic of type 2 diabetes and associated complications of hypertension. Water and 12% ethanol extracts of native Peruvian fruits such as Lucuma (Pouteria lucuma), Pacae (Inga feuille), Papayita arequipeña (Carica pubescens), Capuli (Prunus capuli), Aguaymanto (Physalis peruviana), and Algarrobo (Prosopis pallida) were evaluated for total phenolics, antioxidant activity based on 2, 2-diphenyl-1-picrylhydrazyl radical scavenging assay, and functionality such as in vitro inhibition of alpha-amylase, alpha-glucosidase, and angiotensin I-converting enzyme (ACE) relevant for potential management of hyperglycemia and hypertension linked to type 2 diabetes. The total phenolic content ranged from 3.2 (Aguaymanto) to 11.4 (Lucuma fruit) mg/g of sample dry weight. A significant positive correlation was found between total phenolic content and antioxidant activity for the ethanolic extracts. No phenolic compound was detected in Lucuma (fruit and powder) and Pacae. Aqueous extracts from Lucuma and Algarrobo had the highest alpha-glucosidase inhibitory activities. Papayita arequipeña and Algarrobo had significant ACE inhibitory activities reflecting antihypertensive potential. These in vitro results point to the excellent potential of Peruvian fruits for food-based strategies for complementing effective antidiabetes and antihypertension solutions based on further animal and clinical studies. PMID:19459727

  14. Determination of some physicochemical characteristics, bioactive compounds and antioxidant activity of tropical fruits from Yucatan, Mexico.

    PubMed

    Moo-Huchin, Víctor M; Estrada-Mota, Iván; Estrada-León, Raciel; Cuevas-Glory, Luis; Ortiz-Vázquez, Elizabeth; Vargas y Vargas, María de Lourdes; Betancur-Ancona, David; Sauri-Duch, Enrique

    2014-01-01

    The aim to the study was to determine the physicochemical composition, bioactive compounds and antioxidant activity of fruits from Yucatan, Mexico such as star apple, cashew, mombin, mamey sapote, white sapote, sugar apple, sapodilla, dragon fruit, nance, ilama, custard apple, mamoncillo and black sapote. The physicochemical characteristics were different between fruits and were good sources of bioactive compounds. The edible part with the highest values of antioxidant activity were mamoncillo, star apple, mombin, cashew, white sapote, ilama, custard apple, sugar apple, and nance. Total soluble phenols content showed a correlation with antioxidant activity by ABTS (R=0.52, P⩽0.05) and DPPH (R=0.43, P⩽0.05). A high correlation was obtained between the two assays (ABTS and DPPH) used to measure antioxidant activity in the tropical fruit species under study (R=0.82, P⩽0.05). The results show promising perspectives for the exploitation and use of tropical fruits studied with significant levels of nutrients and antioxidant activity. PMID:24444968

  15. Antioxidant activity, ascorbic acid and total phenol of exotic fruits occurring in Brazil.

    PubMed

    de Assis, Sandra Aparecida; Vellosa, José Carlos Rebuglio; Brunetti, Iguatemy Lourenço; Khalil, Najeh Maissar; Leite, Kátia Maria da Silva Cerqueira; Martins, Antonio Baldo Geraldo; Oliveira, Olga Maria Mascarenhas de Faria

    2009-08-01

    The antioxidant activity, ascorbic acid and phenolic content were studied in 10 exotic fruits from Brazil: abiu, acerola, wax jambu, cashew, mamey sapote, carambola or star fruit, Surinam cherry, longan, sapodilla and jaboticaba. The ascorbic acid was determined by 2,6-dichloroindophenol titrimetic methods and total phenols were measured colorimetrically using the Folin-Ciocalteu reagent. The antioxidant activity was investigated with three different methods: hypochlorous acid scavenging activity, 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation decolorization assay, and 2,2-diphenyl-1-picrylhydrazyl radical scavenging method. The highest content of vitamin C (1,525.00 mg/100 g pulp) occurred in acerola. The total phenol content was higher in abiu, acerola, Surinam cherry and sapodilla. In relation to antioxidant activity, acerola has showed the great values in all three different methods tested. It was found that the fruits have a significant antioxidant effect when tested by each method, respectively, and these antioxidant capacities are promising. The sample concentration also influenced its antioxidant power. PMID:18785051

  16. Road and stream network connectivity and potential: northeastern Puerto Rico, an exploratory analysis

    NASA Astrophysics Data System (ADS)

    Sherrill, K. R.; Laituri, M. J.; Helmer, E. H.; Ramirez, J. A.; Blanco, J. F.; Hein, K.; Pike, A. S.

    2008-07-01

    Interactions between road and stream networks are complex and are influenced by a range of environmental and road design characteristics. These interactions are not clearly understood and are the subjects of current research. To increase understanding of these interactions we explore the concepts of Road and Stream Network Connectivity (R/S Connectivity) and Road and Stream Network Connectivity Potential (RSNCP). Lastly we provide a methodology for study and analysis of R/S connectivity. This study focuses on road induced alterations to sediment and water flow processes, which are important road effects of R/S connectivity. For 25 river road crossings (RRC) in the Rio Mameyes and Rio Espiritu watersheds of Northeastern Puerto Rico, a multi-scale Geographic Information Systems (GIS) database measuring environmental and road characteristic variables was developed specifically to measure variables influencing sediment and water flow. Multivariate analysis methods were used to select the environmental and road characteristic variables which were used in multiple linear regression models for three biota variables (Decapod Richness, Adult Fish Richness, and Total Richness), and four stream habitat geomorphology variables (Median Channel Grain Size, Active Channel Maximum Depth, Pool Volume, and Active Channel Width). Explained variance (R2) from modeling results ranged from 0.22 to 0.86, demonstrating that the GIS derived variables can successfully be used to model important stream biota and geomorphology response variables.

  17. Modelling of Rainfall Induced Landslides in Puerto Rico

    NASA Astrophysics Data System (ADS)

    Lepore, C.; Arnone, E.; Sivandran, G.; Noto, L. V.; Bras, R. L.

    2010-12-01

    We performed an island-wide determination of static landslide susceptibility and hazard assessment as well as dynamic modeling of rainfall-induced shallow landslides in a particular hydrologic basin. Based on statistical analysis of past landslides, we determined that reliable prediction of the susceptibility to landslides is strongly dependent on the resolution of the digital elevation model (DEM) employed and the reliability of the rainfall data. A distributed hydrology model, Triangulated Irregular Network (TIN)-based Real-time Integrated Basin Simulator with VEGetation Generator for Interactive Evolution (tRIBS-VEGGIE), tRIBS-VEGGIE, has been implemented for the first time in a humid tropical environment like Puerto Rico and validated against in-situ measurements. A slope-failure module has been added to tRIBS-VEGGIE’s framework, after analyzing several failure criterions to identify the most suitable for our application; the module is used to predict the location and timing of landsliding events. The Mameyes basin, located in the Luquillo Experimental Forest in Puerto Rico, was selected for modeling based on the availability of soil, vegetation, topographical, meteorological and historic landslide data. Application of the model yields a temporal and spatial distribution of predicted rainfall-induced landslides.

  18. Neuritogenic and neuroprotective activities of fruit residues.

    PubMed

    Tadtong, Sarin; Kanlayavattanakul, Mayuree; Lourith, Nattaya

    2013-11-01

    Neuritogenic and neuroprotective activities of litchi (Litchi chinensis Sonn., Sapindaceae) and salacca (Salacca edulis Reinw., Arecaceae) pericarp, and sapodilla (Achras sapota L., Sapotaceae) and tamarind Srichompu cultivar (Tamarindus indica L., Caesalpiniaceae) seed coat extracts were evaluated on cultured cholinergic P19-derived neurons. All the extracts, at a very low concentration (1 ng/mL of litchi and salacca pericarp extracts, 10 ng/mL of sapodilla and 100 ng/mL of tamarind seed coat extracts), enhanced the survival of cultured neurons (% viability more than 100%) by XTT reduction assay. The extracts were further evaluated for their neuritogenicity by observing cell morphology by phase-contrast microscopy and neuroprotective activity in serum deprivation and pre- and co-administration of hydrogen peroxide models. The phase-contrast micrographs displayed that all of the extracts possessed neurogenic activity by promoting the neurite outgrowth of the cultured neurons. Moreover, these extracts can protect neurons from oxidative stress-caused cell death in a serum deprivation model, and prevent and protect neuron cells from the toxicity of hydrogen peroxide. In this study we assured that the neuritogenic and neuroprotective activities of these extracts derived from the phenolic components and flavonoids contained in the extracts by acting as signaling molecules to enhance neuron survival and promote neurite outgrowth. These results suggest that all of the extracts are potentially sources of neuritogenic and neuroprotective components which might be used either as pharmaceutical products or dietary supplements for neurodegenerative disorder patients, for example, those suffering from Alzheimer's disease. PMID:24427947

  19. Performance of seedlings of a shade-tolerant tropical tree species after moderate addition of N and P

    NASA Astrophysics Data System (ADS)

    Cárate Tandalla, Daisy; Leuschner, Christoph; Homeier, Jürgen

    2015-12-01

    Nitrogen deposition to tropical forests is predicted to increase in future in many regions due to agricultural intensification. We conducted a seedling transplantation experiment in a tropical premontane forest in Ecuador with a locally abundant late-successional tree species (Pouteria torta, Sapotaceae) aimed at detecting species-specific responses to moderate N and P addition and to understand how increasing nutrient availability will affect regeneration. From locally collected seeds, 320 seedlings were produced and transplanted to the plots of the Ecuadorian Nutrient Manipulation Experiment (NUMEX) with three treatments (moderate N addition: 50 kg N ha-1 yr-1, moderate P addition: 10 kg P ha-1 yr-1 and combined N and P addition) and a control (80 plants per treatment). After 12 months, mortality, relative growth rate, leaf nutrient content and leaf herbivory rate were measured. N and NP addition significantly increased the mortality rate (70 % vs. 54 % in the control). However, N and P addition also increased the diameter growth rate of the surviving seedlings. N and P addition did not alter foliar nutrient concentrations and leaf N:P ratio, but N addition decreased the leaf C:N ratio and increased SLA. P addition (but not N addition) resulted in higher leaf area loss to herbivore consumption and also shifted carbon allocation to root growth. This fertilization experiment with a common rainforest tree species conducted in old-growth forest shows that already moderate doses of added N and P are affecting seedling performance which most likely will have consequences for the competitive strength in the understory and the recruitment success of P. torta. Simultaneous increases in growth, herbivory and mortality rates make it difficult to assess the species' overall performance and predict how a future increase in nutrient deposition will alter the abundance of this species in the Andean tropical montane forests.

  20. Integration of a Physically based Distributed Hydrological Model with a Model of Carbon and Nitrogen Cycling: A Case Study at the Luquillo Critical Zone Observatory, Puerto Rico

    NASA Astrophysics Data System (ADS)

    Bastola, S.; Dialynas, Y. G.; Bras, R. L.; Arnone, E.; Noto, L. V.

    2015-12-01

    The dynamics of carbon and nitrogen cycles, increasingly influenced by human activities, are the key to the functioning of ecosystems. These cycles are influenced by the composition of the substrate, availability of nitrogen, the population of microorganisms, and by environmental factors. Therefore, land management and use, climate change, and nitrogen deposition patterns influence the dynamics of these macronutrients at the landscape scale. In this work a physically based distributed hydrological model, the tRIBS model, is coupled with a process-based multi-compartment model of the biogeochemical cycle to simulate the dynamics of carbon and nitrogen (CN) in the Mameyes River basin, Puerto Rico. The model includes a wide range of processes that influence the movement, production, alteration of nutrients in the landscape and factors that affect the CN cycling. The tRIBS integrates geomorphological and climatic factors that influence the cycling of CN in soil. Implementing the decomposition module into tRIBS makes the model a powerful complement to a biogeochemical observation system and a forecast tool able to analyze the influences of future changes on ecosystem services. The soil hydrologic parameters of the model were obtained using ranges of published parameters and observed streamflow data at the outlet. The parameters of the decomposition module are based on previously published data from studies conducted in the Luquillio CZO (budgets of soil organic matter and CN ratio for each of the dominant vegetation types across the landscape). Hydrological fluxes, wet depositon of nitrogen, litter fall and its corresponding CN ratio drive the decomposition model. The simulation results demonstrate a strong influence of soil moisture dynamics on the spatiotemporal distribution of nutrients at the landscape level. The carbon in the litter pool and the nitrate and ammonia pool respond quickly to soil moisture content. Moreover, the CN ratios of the plant litter have

  1. Assessment of Concentrations of Heavy Metals and Phthalates in Two Urban Rivers of the Northeast of Puerto Rico

    PubMed Central

    Ortiz-Colón, Ana I; Piñero-Santiago, Luis E; Rivera, Nilsa M; Sosa, María A

    2016-01-01

    Urbanization adjacent to rivers has increased in recent years and is considered a source of environmental contamination. The resulting increase in number of urban rivers in highly populated areas, such as the Caribbean island of Puerto Rico, has led to the appearance of synthetic as well as naturally occurring chemicals not previously observed nor regularly monitored in freshwater habitats. Some of these chemicals, such as heavy metals and plasticizers, have been shown to affect endocrine, respiratory, and nervous system function in animals and humans, even at relatively low concentrations. The purpose of this study was to measure concentrations of such emergent contaminants on rivers of urbanized areas on the northeast of Puerto Rico, as one element in the assessment of the impact of urbanism on water quality in these communities. To accomplish this, we used Inductively Coupled Plasma and Gas Chromatography Mass Spectrometry to measure amounts of heavy metals and phthalates, respectively, in superficial water of three rivers of Puerto Rico: Mameyes (non-urban), Río Piedras (urban river without a dam), and La Plata (urban river with a dam). The urban rivers had significantly higher concentrations of heavy metals arsenic, barium, cadmium, manganese, and antimony, when compared with the reference non-urban river. Manganese was the only metal found in concentrations higher than limits established by the EPA for drinking water. Of eight phthalates amenable to measurement with the chosen protocol and instrumentation, only dibutyl phthalate was detected, only in the La Plata river, and at concentrations ranging from 3 to 8 parts-per-billion. These findings suggest that urbanism close to rivers of Puerto Rico is likely having an impact on water quality and thus further study to identify the potential sources, as well as the inclusion of these emergent contaminants on the list of chemicals regularly monitored by government agencies is justified. PMID:27148470

  2. Latin American food sources of carotenoids.

    PubMed

    Rodriguez-Amaya, D B

    1999-09-01

    Latin America has a wide variety of carotenogenic foods, notable for the diversity and high levels of carotenoids. A part of this natural wealth has been analyzed. Carrot, red palm oil and some cultivars of squash and pumpkin are sources of both beta-carotene and alpha-carotene. beta-carotene is the principal carotenoid of the palm fruits burití, tucumã and bocaiuva, other fruits such as loquat, marolo and West Indian cherry, and sweet potato. Buriti also has high amounts of alpha-carotene and gamma-carotene. beta-Cryptoxanthin is the major carotenoid in caja, nectarine, orange-fleshed papaya, orange, peach, tangerine and the tree tomato. Lycopene predominates in tomato, red-fleshed papaya, guava, pitanga and watermelon. Pitanga also has substantial amounts of beta-cryptoxanthin, gamma-carotene and rubixanthin. Zeaxanthin, principal carotenoid of corn, is also predominant only in piquí. delta-Carotene is the main carotenoid of the peach palm and zeta-carotene of passion fruit. Lutein and beta-carotene, in high concentrations, are encountered in the numerous leafy vegetables of the region, as well as in other green vegetables and in some varieties of squash and pumpkin. Violaxanthin is the principal carotenoid of mango and mamey and is also found in appreciable amounts in green vegetables. Quantitative, in some cases also qualitative, differences exist among cultivars of the same food. Generally, carotenoids are in greater concentrations in the peel than in the pulp, increase considerably during ripening and are in higher levels in foods produced in hot places. Other Latin America indigenous carotenogenic foods must be investigated before they are supplanted by introduced crops, which are often poorer sources of carotenoids. PMID:10971848

  3. Droplets to Deluges: Combining Stable-Isotope and Meteorological Data to Resolve Climate Controls on Recharge and Runoff in Tropical Watersheds

    NASA Astrophysics Data System (ADS)

    Scholl, M. A.

    2015-12-01

    Determining which rain-producing weather patterns contribute most to water supply is important in areas where climate change is expected to influence large-scale atmospheric parameters controlling precipitation. Tropical mountain watersheds receive high rainfall, but their resilience to drought conditions is not well understood. Their hydrology may include extremely frequent small precipitation events as well as infrequent events with extreme amounts. Isotope hydrology studies in the Luquillo Mountains, Puerto Rico (LUQ) and the Hawaiian Islands compared rain, cloud water, stream and groundwater measurements to build understanding of the climate patterns that contribute to recharge and baseflow. Despite small annual fluctuation in land surface temperature, precipitation stable isotope composition varied seasonally, had a large range (δ 18O = -0.73 to -20.4‰, δ 2H = +12 to -154‰) and correlated with cloud altitude (atmospheric temperature) and storm history in both places. Permeability, storage capacity and antecedent moisture control how rainfall is partitioned into overland flow, plant-available soil moisture, and shallow and deep groundwater pathways on its way to the stream channel. In LUQ, orographic rain and cloud water were more important than convective rainfall in maintaining baseflow; a significant proportion of convective rainfall became runoff. In contrast, stream isotopic composition showed that a large storm supplied baseflow for 18 months in Hawaiian volcanic terrane. Over 3 years in LUQ, seasonal variation in deuterium excess indicated runoff in the 1780 ha Mameyes basin was about 25% quickflow (transit time < 7 days) and 75% groundwater. In a 1.5 ha headwater catchment, nightly cloud water deposition sustained stream water levels, and cloud water contribution to streamflow was evident in isotopic samples. Further research linking weather patterns, precipitation, and subsurface flow partitioning will help with water management in a changing

  4. River Suspended Sediment and Particulate Organic Carbon Transport in Two Montane Catchments in the Luquillo Critical Zone Observatory of Puerto Rico over 25 years: 1989 to 2014

    NASA Astrophysics Data System (ADS)

    Clark, K. E.; Plante, A. F.; Willenbring, J. K.; Jerolmack, D. J.; Gonzalez, G.; Stallard, R. F.; Murphy, S. F.; Vann, D. R.; Leon, M.; McDowell, W. H.

    2015-12-01

    Physical erosion in mountain catchments mobilizes large amounts of sediment, while exporting carbon and nutrients from forest ecosystems. This study expands from previous studies quantifying river suspended sediment and particulate organic carbon loads in the Luquillo Critical Zone Observatory, in Puerto Rico. We evaluate the influences on river suspended load due to i) underlying basin geology, ii) hillslope debris and biomass supply, and iii) hurricanes and large storms. In the Mameyes and Icacos catchments of the Luquillo Mountains, we estimate suspended sediment and particulate organic carbon yields over a 25-year period using streamflow discharge determined from stage measurements at 15-intervals, with estimates of discharge replacing gaps in data, and over 3000 suspended sediment samples. We estimate variation in suspended sediment loads over time, and examine variation in particulate organic carbon loads. Mass spectrometry was used to determine organic carbon concentrations. We confirm that higher suspended sediment fluxes occurred i) in the highly weathered quartz diorite catchment rather than the predominantly volcaniclastic catchment, ii) on the rising limb of the hydrograph once a threshold discharge had been reached, and iii) during hurricanes and other storm events, and we explore these influences on particulate organic carbon transport. Transport of suspended sediment and particulate organic carbon in the rivers shows considerable hysteresis, and we evaluate the extent to which hysteresis affects particulate fluxes over time and between catchments. Because particulate organic carbon is derived from the critical zone and transported during high flow, our research highlights the role of major tropical storms in controlling carbon storage in the critical zone and the coastal ocean.

  5. Decomposition dynamics of mixed litter in a seasonally flooded forest near the Orinoco river

    NASA Astrophysics Data System (ADS)

    Bastianoni, Alessia; Chacón, Noemí; Méndez, Carlos L.; Flores, Saúl

    2015-04-01

    We evaluated the decomposition of a litter mixture in the seasonally flooded forest of a tributary of the Orinoco river. This mixture was prepared using three litter species, based on the litter fall rate observed over a complete hydro-period (2012-2013). The mixture loading ratio was 0.46 of Pouteria orinocoensis (Sapotaceae), 0.38 of Alibertia latifolia (Rubiaceae) and 0.16 of Acosmium nitens (Fabaceae). The initial chemical composition of each single litter species was also determined. Litterbags (20 × 20 cm, 2 mm opening) containing either each single species or the mixture, were deployed on the flooded forest soil and sampled after 30, 240, 270, 300 and 330 days. There were differences in initial total N and P concentrations, with A. nitens (AN) showing the highest nutrient concentrations (%NAN = 1.86 ± 0.19; %PAN = 0.058 ± 0.008) and P. orinocoensis (PO) and A. latifolia (AL) the lowest (%NPO = 0.92 ± 0.06; %NAL = 1.04 ± 0.04; %PPO = 0.029 ± 0.005; %PAL = 0.032 ± 0.001). Litter from AN showed the greatest mass loss (55%) and fastest decomposition rate (k = 0.00185 ± 0.00028) while litter from AL and the mixture showed the smallest mass loss (24% and 27% respectively) and the slowest decomposition rate (kAL = 0.00078 ± 0.00012 and kMIX = 0.00077 ± 0.00006). Decomposition rates were significantly and positively correlated with initial N (r = 0.556, p < 0.05) and P concentrations (r = 0.482, p < 0.05). Nevertheless, there were no significant differences between the expected decomposition rate and the observed decomposition rate of the mixture (additive response). To test the nature of the additivity, an enhancement factor (f) on decomposition rates for each single species was calculated. The species with the highest and smallest value of f were AN and AL, respectively. The fact that two out of the three species had values significantly different from 1, suggests that the additivity detected in our mixture was a consequence of the counterbalancing of

  6. Exchange fluxes of NO2 and O3 at soil and leaf surfaces in an Amazonian rain forest

    NASA Astrophysics Data System (ADS)

    Gut, A.; Scheibe, M.; Rottenberger, S.; Rummel, U.; Welling, M.; Ammann, C.; Kirkman, G. A.; Kuhn, U.; Meixner, F. X.; Kesselmeier, J.; Lehmann, B. E.; Schmidt, W.; Müller, E.; Piedade, M. T. F.

    2002-10-01

    Trace gas exchange of NO2 and O3 at the soil surface of the primary rain forest in Reserva Biológica Jarú (Rondônia, Brazil) was investigated by chamber and gradient methods. The ground resistance to NO2 and O3 deposition to soil was quantified for dry and wet surface conditions using dynamic chambers and was found to be fairly constant at 340 ± 110 and 190 ± 70 s m-1, respectively. For clear-sky conditions, the thermal stratification of the air in the first meter from the forest floor was stable during daytime and unstable during nighttime. The aerodynamic resistance to NO2 and O3 deposition to the ground in the first meter above the forest floor was determined by measurements of 220Rn and CO2 concentration gradients and CO2 surface fluxes. The aerodynamic resistance of the 1-m layer above the ground was 1700 s m-1 during daytime and 600 s m-1 during nighttime. The deposition flux of O3 and NO2 was quantified for clear-sky conditions from the measured concentrations and the quantified resistances. For both trace gases, deposition to the soil was generally observed. The O3 deposition flux to the soil was only significantly different from zero during daytime. The maximum of -1.2 nmol m-2 s-1 was observed at about 1800 and the mean daytime flux was -0.5 nmol m-2 s-1. The mean NO2 deposition flux during daytime was -1.6 ng N m-2 s-1 and during nighttime -2.2 ng N m-2 s-1. The NOx budget at the soil surface yielded net emission day and night. The NO2 deposition flux was 74% of the soil NO emission flux during nighttime and 34% during daytime. The plant uptake of NO2 and O3 by the leaves of Laetia corymbulosa and Pouteria glomerata, two typical plant species for the Amazon rain forest, was investigated in a greenhouse in Oldenburg (Germany) using branch cuvettes. The uptake of O3 was found to be completely under stomatal control. The uptake of NO2 was also controlled by the stomatal resistance but an additional mesophyll resistance of the same order of magnitude as

  7. The Imbert Formation of northern Hispaniola: a tectono-sedimentary record of arc-continent collision and ophiolite emplacement in the northern Caribbean subduction-accretionary prism

    NASA Astrophysics Data System (ADS)

    Escuder-Viruete, J.; Suárez-Rodríguez, A.; Gabites, J.; Pérez-Estaún, A.

    2015-06-01

    In northern Hispaniola, the Imbert Formation (Fm) has been interpreted as an orogenic "mélange" originally deposited as trench-fill sediments, an accretionary (subduction) complex formed above a SW-dipping subduction zone, or the sedimentary result of the early oblique collision of the Caribbean plate with the Bahama Platform in the middle Eocene. However, new stratigraphical, structural, geochemical and geochronological data from northern Hispaniola indicate that the Imbert Fm constitutes a coarsening-upward stratigraphic sequence that records the transition of the sedimentation from a pre-collisional forearc to a syn-collisional piggy-back basin. This piggy-back basin was transported on top of the Puerto Plata ophiolitic complex slab and structurally underlying accreted units of the Rio San Juan complex, as it was emplaced onto the North America continental margin units. The Imbert Fm unconformably overlies different structural levels of the Caribbean subduction-accretionary prism, including a supra-subduction zone ophiolite, and consists of three laterally discontinuous units that record the exhumation of the underlying basement. The distal turbiditic lower unit includes the latest volcanic activity of the Caribbean island arc; the more proximal turbiditic intermediate unit is moderately affected by syn-sedimentary faulting; and the upper unit is a (caotic) olistostromic unit, composed of serpentinite-rich polymictic breccias, conglomerates and sandstones, strongly deformed by syn-sedimentary faulting, slumping and sliding processes. The Imbert Fm is followed by subsidence and turbiditic deposition of the overlying El Mamey Group. The 40Ar / 39Ar plagioclase plateau ages obtained in gabbroic rocks from the Puerto Plata ophiolitic complex indicate its exhumation at ∼ 45-40 Ma (lower-to-middle Eocene), contemporaneously to the sedimentation of the overlying Imbert Fm. These cooling ages imply the uplift to the surface and submarine erosion of the complex to

  8. The Imbert Formation of northern Hispaniola: a tectono-sedimentary record of arc-continent collision and ophiolite emplacement in the northern Caribbean subduction-accretionary prism

    NASA Astrophysics Data System (ADS)

    Escuder-Viruete, J.; Suárez-Rodríguez, Á.; Gabites, J.; Pérez-Estaún, A.

    2016-01-01

    In northern Hispaniola, the Imbert Formation (Fm) has been interpreted as an orogenic "mélange" originally deposited as trench-fill sediments, an accretionary (subduction) complex formed above a SW-dipping subduction zone, or the sedimentary result of the early oblique collision of the Caribbean plate with the Bahama Platform in the middle Eocene. However, new stratigraphical, structural, geochemical and geochronological data from northern Hispaniola indicate that the Imbert Fm constitutes a coarsening-upward stratigraphic sequence that records the transition of the sedimentation from a pre-collisional forearc to a syn-collisional basin. This basin was transported on top of the Puerto Plata ophiolitic complex slab and structurally underlying accreted units of the Rio San Juan complex, as it was emplaced onto the North America continental margin units.

    The Imbert Fm unconformably overlies different structural levels of the Caribbean subduction-accretionary prism, including a supra-subduction zone ophiolite, and consists of three laterally discontinuous units that record the exhumation of the underlying basement. The distal turbiditic lower unit includes the latest volcanic activity of the Caribbean island arc; the more proximal turbiditic intermediate unit is moderately affected by syn-sedimentary faulting; and the upper unit is a (chaotic) olistostromic unit, composed of serpentinite-rich polymictic breccias, conglomerates and sandstones, strongly deformed by syn-sedimentary faulting, slumping and sliding processes. The Imbert Fm is followed by subsidence and turbiditic deposition of the overlying El Mamey Group.

    The 40Ar / 39Ar plagioclase plateau ages obtained in gabbroic rocks from the Puerto Plata ophiolitic complex indicate its exhumation at ˜ 45-40 Ma (lower-to-middle Eocene), contemporaneously to the sedimentation of the overlying Imbert Fm. These cooling ages imply the uplift to the surface and submarine erosion of the complex to

  9. Approaches to stream solute load estimation for solutes with varying dynamics from five diverse small watershed

    USGS Publications Warehouse

    Aulenbach, Brent T.; Burns, Douglas A.; Shanley, James B.; Yanai, Ruth D.; Bae, Kikang; Wild, Adam; Yang, Yang; Yi, Dong

    2016-01-01

    Estimating streamwater solute loads is a central objective of many water-quality monitoring and research studies, as loads are used to compare with atmospheric inputs, to infer biogeochemical processes, and to assess whether water quality is improving or degrading. In this study, we evaluate loads and associated errors to determine the best load estimation technique among three methods (a period-weighted approach, the regression-model method, and the composite method) based on a solute's concentration dynamics and sampling frequency. We evaluated a broad range of varying concentration dynamics with stream flow and season using four dissolved solutes (sulfate, silica, nitrate, and dissolved organic carbon) at five diverse small watersheds (Sleepers River Research Watershed, VT; Hubbard Brook Experimental Forest, NH; Biscuit Brook Watershed, NY; Panola Mountain Research Watershed, GA; and Río Mameyes Watershed, PR) with fairly high-frequency sampling during a 10- to 11-yr period. Data sets with three different sampling frequencies were derived from the full data set at each site (weekly plus storm/snowmelt events, weekly, and monthly) and errors in loads were assessed for the study period, annually, and monthly. For solutes that had a moderate to strong concentration–discharge relation, the composite method performed best, unless the autocorrelation of the model residuals was <0.2, in which case the regression-model method was most appropriate. For solutes that had a nonexistent or weak concentration–discharge relation (modelR2 < about 0.3), the period-weighted approach was most appropriate. The lowest errors in loads were achieved for solutes with the strongest concentration–discharge relations. Sample and regression model diagnostics could be used to approximate overall accuracies and annual precisions. For the period-weighed approach, errors were lower when the variance in concentrations was lower, the degree of autocorrelation in the concentrations was

  10. Quantification soil production and erosion using isotopic techniques

    NASA Astrophysics Data System (ADS)

    Dosseto, Anthony; Suresh, P. O.

    2010-05-01

    Soil is a critical resource, especially in the context of a rapidly growing world's population. Thus, it is crucial to be able to quantify how soil resources evolve with time and how fast they become depleted. Over the past few years, the application of cosmogenic isotopes has permitted to constrain rates of soil denudation. By assuming constant soil thickness, it is also possible to use these denudation rates to infer soil production rates (Heimsath et al. 1997). However, in this case, it is not possible to discuss any imbalance between erosion and production, which is the core question when interested in soil resource sustainability. Recently, the measurement of uranium-series isotopes in soils has been used to quantify the residence time of soil material in the weathering profile and to infer soil production rates (Dequincey et al. 2002; Dosseto et al. 2008). Thus, the combination of U-series and cosmogenic isotopes can be used to discuss how soil resources evolve with time, whether they are depleting, increasing or in steady-state. Recent work has been undertaken in temperate southeastern Australia where a several meters thick saprolite is developed over a graniodioritc bedrock and underlains a meter or less of soil (Dosseto et al., 2008) and in tropical Puerto Rico, also in a granitic catchment. Results show that in an environment where human activity is minimal, soil and saprolite are renewed as fast as they are destroyed through denudation. Further work is investigating these processes at other sites in southeastern Australia (Frogs Hollow; Heimsath et al. 2001) and Puerto Rico (Rio Mameyes catchment; andesitic bedrock). Results will be presented and a review of the quantification of the rates of soil evolution using isotopic techniques will be given. Dequincey, O., F. Chabaux, et al. (2002). Chemical mobilizations in laterites: Evidence from trace elements and 238U-234U-230Th disequilibria. Geochim. Cosmochim. Acta 66(7): 1197-1210. Dosseto, A., S. P

  11. The Relative Importance of Convective and Trade-wind Orographic Precipitation to Streamflow in the Luquillo Mountains, Eastern Puerto Rico

    NASA Astrophysics Data System (ADS)

    Scholl, M. A.; Shanley, J. B.; Occhi, M.; Scatena, F. N.

    2012-12-01

    Like many mountainous areas in the tropics, watersheds in the Luquillo Mountains of Puerto Rico (18.3° N) have abundant rainfall and stream discharge, but relatively little storage capacity. Therefore, the water supply is vulnerable to drought and water availability may be affected by projected changes in regional temperature and atmospheric dynamics due to global warming. To help determine the links between climate and water availability, precipitation patterns were analyzed, and stable-isotope signatures of precipitation from different seasonal weather systems were established to identify those that are most important in maintaining streamflow and groundwater recharge. Stable isotope data include cloud water, rainfall, throughfall, streamflow, and groundwater from the Rio Mameyes and Rio Icacos/ Rio Blanco watersheds. Precipitation inputs have a wide range of stable isotope values, from fog/cloud water with δ2H and δ18O averaging +3.2‰, -1.74‰ respectively, to tropical storm rain with values as low as -154‰, -20.4‰. Spatial and temporal patterns of water isotopic values on this Caribbean island are different than higher latitude, continental watersheds. The data exhibit a 'reverse seasonality', with higher isotopic values in winter and lower values in summer; and stable isotope values of stream water do not decrease as expected with increasing altitude, because of cloud water input. Rain isotopic values vary predictably with local and mesoscale weather patterns and correlate strongly with cloud altitude. This correlation allows us to assign isotopic signatures to different sources of precipitation, and to investigate which climate patterns contribute to streamflow and groundwater recharge. At a measurement site at 615 m in the Luquillo Mountains, the average length of time between rain events was 15 h, and 45% of the rain events were <2 mm, reflecting the frequent small rain events of the trade-wind orographic rainfall weather pattern. Long

  12. Stable Isotopes (δ18O and δ2H) Help to Delineate Flow Paths and the Importance of Different Climate Patterns in Watersheds of the Luquillo Mountains, Puerto Rico

    NASA Astrophysics Data System (ADS)

    Scholl, M. A.; Shanley, J. B.; Scatena, F. N.

    2009-12-01

    altitudes in the Icacos and Mameyes watersheds suggests that the low-intensity trade-wind showers contribute a greater proportion of stream baseflow than do high-intensity rain events. High-intensity rain events run off quickly and may not effectively infiltrate the saturated tropical soils. The seasonal cycle of rain isotopic composition is also reflected in the streams and can be utilized to estimate contributions from shallow and deep flow paths for both watersheds.

  13. Field evidence of two-phase abrasion process

    NASA Astrophysics Data System (ADS)

    Miller, K. L.; Szabo, T.; Jerolmack, D. J.; Domokos, G.

    2013-12-01

    The rounded shape of river rocks is clear evidence that abrasion due to bed load transport is a significant agent for mass loss. Its contribution to downstream fining, however, is typically assumed to be negligible - as diminution trends may be explained solely by size-selective transport. A recent theory has predicted that pebble abrasion occurs in two well separated phases: in Phase 1, an intially-polyhedral pebble rounds to the shape of an inscribed ellipsoid without any change in axis dimensions; in Phase II, axis dimensions are slowly reduced. Importantly, Phase I abrasion means that an initially-blocky pebble may lose up to half its mass without any apparent change in 'size', which is only measured as the length of a single pebble axis by most field researchers. We hypothesize that field studies have significantly underestimated the importance of abrasion because they do not quantify pebble shape, and we set out to demonstrate that two-phase abrasion occurs in a natural stream. Our study examines downstream trends in pebble size and shape along a 10-km stretch of the Rio Mameyes within the Luquillo Critical Zone observatory, where volcaniclastic cobbles and boulders are transported by bed load at slopes up to 10%. The upper reaches of the stream consist of alluviated bedrock valleys that preclude sediment storage and thus minimize size-selective transport, which allows us to isolate the effects of abrasion. The lower 5 km is an alluvial river in which size-selective transport becomes operative. We quantified the shape and size of thousands of pebbles along the profile using hand and image-based techniques. The data provide the first field validation of two-phase abrasion; in the bedrock reaches, pebbles clearly evolve toward ellipsoids without any significant change in axis dimensions (rounding), while in the lower reaches pebbles slowly reduce their axis dimensions with little or no change in roundness. Results also show that shape metrics determined from

  14. Particle mobility over flood and annual timescales in mountain streams of the Luquillo Critical Zone Observatory

    NASA Astrophysics Data System (ADS)

    Phillips, C. B.; Jerolmack, D. J.

    2011-12-01

    Linking the mechanics of fluvial and hillslope processes is critical for understanding how landscapes are sculpted. Over short timescales, the rate of bed load transport in mountain streams is determined by transport mechanics: channel hydraulics, bed configuration, and the intensity of flow events. At larger timescales, the rate of bed load transport represents the supply of coarse-grained sediment from hillslopes. Linking the mechanics of event-scale bed load transport to longer duration bed load transport rates is necessary for understanding mountain stream dynamics. We present a unique dataset using passive integrated transponder radio frequency identification (PIT RFID) tagged tracer particles in three streams in the humid tropical region of Northeast Puerto Rico. This region receives an average of four meters of precipitation per year. Importantly, precipitation occurs in short duration, high intensity events that are capable of mobilizing coarse sediment multiple times per year. Although landslides and debris flows are active in the area, most river reaches show strong evidence of being organized by bed load transport. The high frequency of cobble/boulder transport makes Luquillo an ideal location to study bed load transport in mountain streams. Tracer particles (375 total) were placed during the summers of 2010 and 2011 in three reaches within the Mameyes river catchment with slopes and drainage areas ranging from .007-.09 and .028-24.2 km2 respectively. Grain size distributions of the median grain diameter for the three study reaches range from 2-1100 mm. Grain size distributions of the tracer particles were picked to match that of the study reach grain size distribution greater than 50 mm. Hydrodynamic forcing was parameterized using a time series of Shields stress, estimated for each reach from nearby USGS stream gaging stations. Tracer particle transport distances were recorded following single events, and on a yearly basis. At the single-flood scale

  15. Deterministic and stochastic dynamics of bed load tracer particles in a coarse grained river

    NASA Astrophysics Data System (ADS)

    Phillips, C. B.; Martin, R. L.; Jerolmack, D. J.

    2012-12-01

    Understanding the mechanics of a single coarse sediment particle, and the mechanics of sediment transport at the flood scale, is critical to linking event scale bed load transport rates to annual bed load fluxes. We present research on the dynamics of coarse sediment tracer particles tagged with passive radio transponder tags, observing motion resulting from individual floods and the cumulative transport over many floods spanning two years, in the Mameyes River in the Luquillo Mountains of Puerto Rico. This region presents an ideal study area due to the high frequency of coarse sediment mobilizing events, which allows us to field test the applicability of recently-proposed deterministic and stochastic theories for particle motion. Data for each flood are composed of (1) measured 'flight' lengths for each transported particle, (2) the fraction of tagged particles mobilized, and (3) high-resolution river stage measurements. At the single flood scale, measured tracer particle flight lengths are exponentially distributed, and modal flight lengths scale linearly with excess shear velocity. This is in quantitative agreement with recent theory and laboratory experiments, suggesting that moving particles' velocity is determined by momentum balance with the fluid. The fraction of mobile particles per event increases rapidly with flood stage, creating a logistic-like curve whose inflection point is used to empirically define the threshold of motion. This finding is in contrast to the linear relation observed in small-scale experiments and predicted from momentum balance between sediment and fluid; we use a particle Stokes number argument to suggest that a collision cascade from grain-grain interactions is responsible for the nonlinear relation between mobile fraction and fluid stress, in dynamical equivalence with aeolian sand transport. To examine particle dispersion and relate it to transport mechanics, it is necessary to remove the time over which the fluid stress is

  16. Filtering mountain landscapes and hydrology through sediment transport

    NASA Astrophysics Data System (ADS)

    Phillips, C. B.; Jerolmack, D. J.

    2013-12-01

    Long-term denudation of landscapes is balanced, and sometimes limited by, the sediment mass flux leaving the system through rivers. Suspended sediment represents the largest fraction of mass exiting the landscape, however coarse bed load transport may be the rate-limiting process of landscape denudation through its control on bedrock channel erosion and incision. We present research linking particle mechanics for a coarse alluvial gravel stream at the flood scale to particle dynamics at the annual timescale, and examine the implications of these results on channel geometry and the hydrology of mountain rivers. We examine the transport dynamics of individual cobbles tagged with passive radio transponder tags from the Mameyes River in the Luquillo Mountains of Puerto Rico, in both bedrock and alluvial stretches. These data are composed of measured 'flight' lengths for each transported particle, the fraction of tagged particles mobilized, and high-resolution river stage measurements. At the single flood scale, measured tracer particle flight lengths are exponentially distributed, and modal flight lengths scale linearly with excess shear velocity (U*-U*c). This is in quantitative agreement with recent theory and laboratory experiments, suggesting that moving particles' velocity is determined by momentum balance with the fluid. Examining tracer displacement at long timescales we use a dimensionless impulse (I*) - obtained by integrating the cumulative excess shear velocity over the duration of a flood (normalized by grain size) - and find that the mean travel distance collapses onto a linear relationship. Data show that partial bed load transport with intermittent motion is the dominant mode for the duration of record. Examining flood statistics, we find that the frequency-magnitude distribution of shear velocity is a power law; however, this scaling is truncated at the threshold of motion, beyond which it displays exponential scaling. The thin-tailed scaling of (U

  17. Nitrate and Phosphate Concentration Trends in Selected Puerto Rico Rivers over the Past Four Decades--The Impact of Human Activity on Tropical Island Landscapes and Water Quality

    NASA Astrophysics Data System (ADS)

    Troester, J. W.

    2001-12-01

    For more than four decades, the U.S. Geological Survey (USGS) has collected riverine nutrient concentration data in Puerto Rico, a mountainous Caribbean tropical island. During the last forty years the population of this 9043 square km island has increased from about 2.4 to 3.8 million people. Much of the island has been developed for agriculture, and later for industry and urbanization. Data from gaging stations located within four of the larger, mixed land-use drainage basins of Puerto Rico were compiled and analyzed. The stations selected were the Rio Grande de Manati at Highway 2 (Station 50038100), Rio de la Plata at Highway 2 (Station 50046000), Rio Grande de Patillas near Patillas (Station 50092000), and Rio Grande de Anasco near San Sebastian (Station 50144000). Analytical results were compared with a shorter-term data set from smaller forested watersheds (that are part of the USGS Water, Energy, and Biogeochemical Budgets (WEBB) Program) to evaluate the impact of human activity on the water quality. During the 1960's, discharge weighted average concentrations (DWAC) of dissolved nitrate-nitrogen (nitrate-N) ranged from 0.10 to 0.51 mg/L in the four rivers. DWAC of nitrate-N increased and peaked in the 1970's and 1980's (range of 0.35 to 1.00 mg/L), and have subsequently decreased (range of 0.30 to 0.95 mg/L). DWAC of nitrate-N declined, even though the average nitrate-N concentration continued to increase in three of these rivers. The decrease in DWAC of nitrate-N may reflect the changes in land use from the 1960's to present, which includes an increase in forest and a decrease in cropland throughout much of Puerto Rico. However, the largest decrease (from 0.77 to 0.34 mg/L) occurred in the Rio de la Plata after it was dammed in 1974. DWAC of nitrate-N in the four rivers were several times higher than the total nitrate-N observed at gaging stations in undisturbed forested watersheds, such as at the Rio Mameyes near Sabana (Station 50065500) and the Rio