Catchment characteristics and soil and water chemistry of the San Francisco basin and subbasins, Ecuador

In this study, the Mean Transit Time and Mixing Model Analysis methods are combined to unravel the runoff generation process of the San Francisco River basin (73.5 km**2) situated on the Amazonian side of the Cordillera Real in the southernmost Andes of Ecuador. The montane basin is covered with cloud forest, sub-páramo, pasture and ferns. Nested sampling was applied for the collection of streamwater samples and discharge measurements in the main tributaries and outlet of the basin, and for the collection of soil and rock water samples. Weekly to biweekly water grab samples were taken at all stations in the period April 2007-November 2008. Hydrometric data, Mean Transit Time and Mixing Model Analysis allowed preliminary evaluation of the processes controlling the runoff in the San Francisco River basin. Results suggest that flow during dry conditions mainly consists of lateral flow through the C-horizon and cracks in the top weathered bedrock layer, and that all subcatchments have an important contribution of this deep water to runoff, no matter whether pristine or deforested. During normal to low precipitation intensities, when antecedent soil moisture conditions favour water infiltration, vertical flow paths to deeper soil horizons with subsequent lateral subsurface flow contribute most to streamflow. Under wet conditions in forested catchments, streamflow is controlled by near surface lateral flow through the organic horizon. Exceptionally, saturation excess overland flow occurs. By absence of the litter layer in pasture, streamflow under wet conditions originates from the A horizon, and overland flow.

Mémoires sur la famille des fougères,

Vol. 10 photostat copy (positive)

Reports upon the botanical collections made in portions of Nevada, Utah, California, Colorado, New Mexico and Arizona, during the years, 1871, 1872, 1873, 1874, and 1875.

Mode of access: Internet.

The fern bulletin.

"A quarterly devoted to ferns."

Fernwort papers presented at a meeting of fern students, held in New York city, June 27, 1900, under the auspices of the Linnaean fern chapter ... .

Cover title.

Les fougères, choix des espèces les plus remarquables pour la décoration des serres, parcs, jardins et salons, précédé de leur histoire botanique & horticole.

Tome 2 has title: Les fougères, nouveaux choix des espèces les plus remarquables pour la décoration des serres, parcs, jardins et salons publi é sous la direction de J. Rothschld, suivi de l'histoire botanique et horticole des sélaginelles par E. Roze.

Papers presented at the Boston meeting, under the auspices of the Linnaean Fern Chapter, August 24, 1898.

Cover title.

Taxonomy of specimens of the Pennsylvanian age Marattialean fern Psaronius from Ohio and Illinois/

Bibliography: p. 61-64.

Filicum species in Horto regio botanico berolinensi cultae /

Stafleu and Cowan (2nd ed.)

Olai Swartz, Synopsis filicum : earum genera et species systematice complectens /

Mode of access: Internet.

Études sur la fronde des Zygoptéridées,

"Bibliographie": p. 281-284.

The fern world.

Mode of access: Internet.

Field identification cards /

A set of individual identification cards for rare and sensitive plant species found in the southeastern United States including Puerto Rico. Categories include forbs, shrubs, ferns, and trees. Each card has a color picture on one side and a description and map on the reverse. The description includes: family, flowering date, habitat, and identifying characteristics.

Fern Valley Trail guide /

"March 1986"--P. 15.

Intake rates and the functional response in shorebirds (Charadriiformes) eating macro-invertebrates

As field determinations take much effort, it would be useful to be able to predict easily the coefficients describing the functional response of free-living predators, the function relating food intake rate to the abundance of food organisms in the environment. As a means easily to parameterise an individual-based model of shorebird Charadriiformes populations, we attempted this for shorebirds eating macro-invertebrates. Intake rate is measured as the ash-free dry mass (AFDM) per second of active foraging; i.e. excluding time spent on digestive pauses and other activities, such as preening. The present and previous studies show that the general shape of the functional response in shorebirds eating approximately the same size of prey across the full range of prey density is a decelerating rise to a plateau, thus approximating the Holling type 11 ('disc equation') formulation. But field studies confirmed that the asymptote was not set by handling time, as assumed by the disc equation, because only about half the foraging time was spent in successfully or unsuccessfully attacking and handling prey, the rest being devoted to searching. A review of 30 functional responses showed that intake rate in free-living shorebirds varied independently of prey density over a wide range, with the asymptote being reached at very low prey densities (< 150/m(-2)). Accordingly, most of the many studies of shorebird intake rate have probably been conducted at or near the asymptote of the functional response, suggesting that equations that predict intake rate should also predict the asymptote. A multivariate analysis of 468 'spot' estimates of intake rates from 26 shorebirds identified ten variables, representing prey and shorebird characteristics, that accounted for 81 % of the variance in logarithm-transformed intake rate. But four-variables accounted for almost as much (77.3 %), these being bird size, prey size, whether the bird was an oystercatcher Haematopus ostralegus eating mussels Mytilus edulis, or breeding. The four variable equation under-predicted, on average, the observed 30 estimates of the asymptote by 11.6%, but this discrepancy was reduced to 0.2% when two suspect estimates from one early study in the 1960s were removed. The equation therefore predicted the observed asymptote very successfully in 93 % of cases. We conclude that the asymptote can be reliably predicted from just four easily measured variables. Indeed, if the birds are not breeding and are not oystercatchers eating mussels, reliable predictions can be obtained using just two variables, bird and prey sizes. A multivariate analysis of 23 estimates of the half-asymptote constant suggested they were smaller when prey were small but greater when the birds were large, especially in oystercatchers. The resulting equation could be used to predict the half-asymptote constant, but its predictive power has yet to be tested. As well as predicting the asymptote of the functional response, the equations will enable research workers engaged in many areas of shorebird ecology and behaviour to estimate intake rate without the need for conventional time-consuming field studies, including species for which it has not yet proved possible to measure intake rate in the field.