In situ agrobiodiversity conservation: Examples from Nepal,Turkey and Switzerland in the first decade of the convention on Biological Diversity

Applications of in situ agrobiodiversity conservation practices within agricultural production systems have the potential to reduce the risks of agricultural modernisation and enhance sustainable development. The aims and approaches for in situ conservation differ according to the requirements of communities and nations. Approaches to in situ conservation in the decade after the Convention of Biological Diversity are reviewed within the contexts of marginal agricultural systems in Nepal, Turkey and Switzerland. Numerous approaches are currently utilised, including: the informal de facto retention of agrobiodiversity; the provision of state assistance; the marketing of agrobiodiversity products; the use of technological innovations to develop local diversity; the establishment of conservation reserves; community assistance programmes and the raising of awareness of the issue amongst all sectors of societies. Emerging complementary in situ approaches applicable in the rural margins suggest a framework for effectively conserving agrobiodiversity by working with local people.     

COMPARISON OF PROCESS‐BASED AND ARTIFICIAL NEURAL NETWORK APPROACHES FOR STREAMFLOW MODELING IN AN AGRICULTURAL WATERSHED1

ABSTRACT: The performance of the Soil and Water Assessment Tool (SWAT) and artificial neural network (ANN) models in simulating hydrologic response was assessed in an agricultural watershed in southeastern Pennsylvania. All of the performance evaluation measures including Nash‐Sutcliffe coefficient of efficiency (E) and coefficient of determination (R²) suggest that the ANN monthly predictions were closer to the observed flows than the monthly predictions from the SWAT model. More specifically, monthly streamflow E and R² were 0.54 and 0.57, respectively, for the SWAT model calibration period, and 0.71 and 0.75, respectively, for the ANN model training period. For the validation period, these values were ?0.17 and 0.34 for the SWAT and 0.43 and 0.45 for the ANN model. SWAT model performance was affected by snowmelt events during winter months and by the model's inability to adequately simulate base flows. Even though this and other studies using ANN models suggest that these models provide a viable alternative approach for hydrologic and water quality modeling, ANN models in their current form are not spatially distributed watershed modeling systems. However, considering the promising performance of the simple ANN model, this study suggests that the ANN approach warrants further development to explicitly address the spatial distribution of hydrologic/water quality processes within watersheds.     

The use of Littorina littorea for tributyltin (TBT) effect monitoring - Results from the German TBT survey 1994/1995 and laboratory experiments

Field investigations and laboratory experiments were performed to test the applicability of the intersex phenomenon in Littorina littorea for biological TBT-effect monitoring and to give further insights into toxicological aspects of intersex development. The intensity of the phenomenon is correlated with the degree of TBT contamination in the environment. Statistically highly significant correlations of biological indices and TBT concentrations in tissue and sediment exist. Intersex can be induced only in juvenile and sexually immature females and its intensity depends on the ontogenetic stage of development during TBT exposure. For the first time, malformations in male periwinkles closely related to the TBT contamination can be described; the reduction of male mamilliform penial glands shows highly significant correlations to TBT concentrations in tissues. The intersex phenomenon in Littorina littorea is proposed for a biological TBT-effect monitoring in those areas where the dogwhelk Nucella lapillus, as the more sensitive species in European surveys, is absent. The intersex index (ISI) as the mean value of the intersex stages in a sample should be used as the most sensitive biological parameter for the assessment of the TBT contamination in Littorina littorea.     

Lead in the diet and body tissues of dunlins, Calidris alpina, from the Bristol Channel, UK

Lead concentrations were determined in the organs of a shorebird, the dunlin, in its main invertebrate prey, and in sediments collected from five sites in the Bristol Channel. The highest sediment concentrations were found in the Taff Estuary (97 microg g(-1) dry mass). The highest concentrations in invertebrates were found in the upper Severn Estuary (45 microg g(-1) dry mass in Nereis diversicolor). In dunlins, the highest concentrations were found in the sternum (25 microg g(-1) dry mass in males), followed by the beak, legs, kidney, liver and pectoral muscle. Adult males contained significantly higher concentrations (ca 20%) than adult females, and in some cases adults had significantly higher concentrations than first year birds (36% higher in the case of the sternum). Lead concentrations tended to increase throughout the winter, being 37-115% higher in the spring. Birds were able to purge themselves of a substantial portion of their body lead burdens, probably during the autumn moult.     

The uptake of particulates by an urban woodland: site description and particulate composition

Woodlands may improve local air quality by increasing the uptake rates of gaseous, particulate and aerosol pollutants from the atmosphere and can also act as relatively permanent sinks for some pollutants. Rough Wood, Walsall was selected for a study of the material which accumulates on tree foliage because of its location in a densely populated urban area, and its proximity to a motorway with high traffic flow (the M6) and to other pollutant sources. Methods were developed for leaf washing to allow determination of the quantity of dust and the identification of the dust particles present on oak leaves. Elemental analysis of particles was also undertaken using scanning electron microscopy coupled with electron probe microanalysis. A large proportion of particles were organic in origin. Of the inorganic particles, the majority contained silicon and aluminium in varying proportions suggesting that they were soil derived. Some particles were clearly identified as the products of combustion, and sea or road salt was present on leaf surfaces. Some particles contained copper, tin and titanium which may reflect the proximity of Rough Wood to local metal workings. The number of particles counted on leaf surfaces decreased as distance from the motorway increased.     

Cu accumulation in the earthworm Dendrobaena veneta in a heavy metal (Cu, Pb, Zn) contaminated site compared to Cu accumulation in laboratory experiments

Earthworms (Dendrobaena veneta) were exposed to heavy metal contaminated soil from a field site under both laboratory and field conditions. In the laboratory study, D. veneta were analysed for Cu after 2 weeks' exposure. The tissue Cu concentration (Cu(W)) increased proportionally with the total extractable soil Cu content (Cu(T)) in soils that contained less than 150 mg Cu kg(-1). In D. veneta exposed to soils containing more than Cu(T) = 150 mg kg(-1), however, we observed no further increase in Cu(W). In a 64-m(2) field plot at a contaminated site, 81 soil samples were taken and analysed for Cu, Pb, Zn and pH. In June 1994, 1000 D. veneta were homogeneously distributed in the plot and sampled after 1, 2 and 5 weeks to analyse for Cu. Additionally, 2000 D. veneta were introduced in September 1994 and sampled after 1, 2 and 4 weeks. At locations where earthworms were removed, the soil Cu content was estimated by disjunctive kriging. Cu concentration factors (ratio of Cu(W) to Cu(T)) in the field experiment were in excellent agreement with those of the laboratory experiment. This indicates that, with a sufficiently high sampling density, it may be feasible to predict earthworm Cu accumulation in the field using a concentration factor determined in the laboratory.     

Age and growth of the alfonsino Beryx splendens over the seamounts off New Caledonia

Age and growth of the alfonsino Beryx splendens from New Caledonia seamounts were determined by examination of whole and sectioned otoliths. One growth-ring (annulus) in the otoliths appears to be laid down each year. It consists of one opaque (summer, fast-growing) zone and one hyaline (winter, slowgrowing) zone. Thin-sections of otoliths revealed daily rings which allowed us to estimate that the formation of the nucleus takes 10 mo. The first annulus following the nucleus is incomplete. Females have a higher growth rate than males. Sexual maturity is reached at the age of 7 to 8 yr for males and 6 yr for females. Maximum age attained would be 20 yr for alfonsino >50 cm in fork length. the results are compared with those from the few other studies on the growth of alfonsino.     

Particle capture in the musselMytilus edulis: The role of latero-frontal cirri

Microscope video graphs of particle paths near one-filament-thick mussel gill preparations, stimulated with a nerve transmitter (10^–6 M serotonin which restores normal ciliary activity), were used to disclose the capture of 6 m algal cells. Suspended algal cells carried with the water were stopped for a while at the entrance to the interfilament gap by the action of the latero-frontal cirri (Ifc), and transferred to the frontal side of the filament to be transported towards the marginal food groove. The event of transfer took place during approximately a time interval of 1150 to 1/25 s. To gain a better understanding of the capture mechanism and retention efficiency versus particle size, the flow through and around the Ifc was theoretically estimated. Normally beating Ifc create periodic, unsteady, three-dimensional flows at the entrance to the interfilament canal. During the active beat most of the water is deflected to flow around the branching cilia of the Ifc while some of the water is strained by these. Large particles (> 4 m) are stopped and transferred to the frontal current, whereas smaller particles either follow the flow around the Ifc and escape or they are stopped by the branching cilia.     

RESOLUTION OF ENDANGERED SPECIES ACT ISSUES IN PERMITTING TILE PLATEAU CREEK PIPELINE1

ABSTRACT: This paper describes how a hydrologic model proved to be a valuable tool to help interested parties understand impacts to four threatened and endangered fish species in the Upper Colorado River. In 1994, the Ute Water Conservancy District initiated permitting and design of the Plateau Creek pipeline replacement. The project was considered a major Federal action and therefore subject to the National Environmental Policy Act. Under Section 7 of the Endangered Species Act, the U.S. Fish and Wildlife Service (USFWS) entered the process to develop a Biological Opinion (BO) and determined that the project could potentially impact the endangered fish in the 15‐mile reach of the Colorado River. The Section 7 consultation was directed by a Core Committee comprised of stakeholders in the Upper Colorado River watershed. Hydrologic modeling became the evaluation tool for comparing flow reductions to USFWS target recovery flows and defining make‐up flow requirements to meet those targets. The Colorado River Recovery Implementation Program was designated to provide the make‐up flows. The USFWS released a final BO in December 1997, approving diversions through 2015. An Environmental Impact Statement for the project was completed and the Record of Decision was issued by the Bureau of Land Management in early 1998.     

An evaluation of three empirical air-to-leaf models for polychlorinated dibenzo-p-dioxins and dibenzofurans

Three empirical air-to-leaf models for estimating grass concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (abbreviated dioxins and furans) from air concentrations of these compounds are described and tested against two field data sets. All are empirical in that they are founded on simplistic bioconcentration and related approaches which rely on field data for their parameterization. One of the models, identified as the EPA Model, partitions the total air concentration into vapor and particle phases, and separately models the impact of both. A second model addresses only the vapor phase; grass concentrations are modeled as a function of vapor deposition. For the third model, it is assumed that the grass plants "scavenge" a fixed volume of air of dioxins, and hence grass concentrations are modeled as a simple product of total air concentration and a constant scavenging coefficient. Field data from two sites, a rural and an industrial site in the United Kingdom, included concurrent measurements of dioxins in air and field grass, and dioxin and furan depositions, for one 6-week sampling period. Principal findings include: (1) the EPA Model underpredicted grass concentrations at the rural field site by a factor of 2, while the Scavenging Model underpredicted grass concentrations by a factor of 3.8, and the Vapor Deposition Model significantly underpredicted grass concentrations (by a factor greater than 10), (2) the presence of high soil concentrations for some of the dioxins and furans at the industrial site appears to have caused higher grass concentrations and confounded the air-to-plant modeling exercise, (3) the Scavenging Model could be calibrated to the data set; however, a key premise of this model that vapor and particle phase dioxins equally impact the plants, is not supported by the field data, (4) measured depositions are highly correlated to but systematically lower than modeled depositions, which could be due to modeling assumptions or a systematic measurement bias.