bluuebunny/crossref_metadata_2025 huggingface dataset:
Pigmented spleens in C57BL mice
Authors: Veninga T. S. , Wieringa R. A. , Morse H.
Published: June 2007

Approximately 15% of our highly inbred C57BL/6 mice show a spleen with a pigmented cranial part. Microscopically, abundant aggregates of pigment granules are observed primarily scattered between cells of the red pulp. They give a positive reaction with Perls' Prussian blue and stain heavily with silver-methenamine. Most of the granules are stored in macrophages. In some cases a number of granules are surrounded by a membrane. This abnormality may be designated haemosiderosis. In the present study we demonstrate that it is not related to the consumption of iron within the range normally found in laboratory animal diets. This suggests a genetic origin, although confirmation would require further research. If so, comparison with human idiopathic haemochromatosis is tempting. However, contrary to the human condition, organs other than the spleen are not affected, with exception of the liver. This organ contains minor deposits of pigment granules. Nor do affected animals appear to show any ill effects. Nevertheless, it seems worthwhile to investigate whether this phenomenon in C57BL mice could serve as a model for the human disease provided that a practical criterium becomes available for detection in the intact animal.
A lobster claw abnormality in the common marmoset (Callithrix jacchus)
Authors: Cooper J. E. , Purton P. , Poswillo D. E.
Published: June 2007

A congenital abnormality of the digits, similar to the 'lobster claw' deformity of humans, was observed in 8 common marmosets. The condition varied in severity and in effect on the animals; it appeared to be due to a single autosomal recessive trait.
Evaluation of vitamin E requirement and food palatability in rabbits fed a purified diet with a high fish oil content
Authors: Verschuren P. M. , Houtsmuller U. M. T. , Zevenbergen J. L.
Published: June 2007

The vitamin E requirement of rabbits fed a semi-synthetic diet containing high amounts of fish oil was studied. Three groups of 5 rabbits were fed fish oil diets containing, respectively, 50, 100 and 500 mg/kg vitamin E. Moreover diet palatability was evaluated by using different levels of grass meal: 0·5, 1 and 2%, respectively. Incorporation of 1% grass meal in the diet was sufficient to achieve acceptance of the fish oil diet. Increased vitamin E intake resulted in a dose-related rise in vitamin E levels in serum, blood platelets, liver and adipose tissue. The higher vitamin E intake was reflected by a twofold increase of vitamin E in serum, platelets and adipose tissue, and a tenfold increase in the liver. The adipose tissue revealed histopathological changes of yellow fat disease, mainly in the low-dose vitamin E group. In the liver microgranulomas of lipofuscin-laden macrophages were seen. Vitamin E was found to decrease but not to prevent the formation of these lesions. The results indicate that protection of marine oils against in vivo oxidation is problematic in the rabbit. It is questionable whether in this animal vitamin E is an adequate biological anti-oxidant for very long chain n-3 fatty acids.
Sequential bronchoalveolar lavages by endotracheal intubation in guineapigs
Authors: Tremblay Guy , Gagnon Louis , Cormier Yvon
Published: June 2007

We examined the feasibility of performing repeated bronchoalveolar lavage (BAL) on guineapigs. We also determined the influence of lavage volume on cell recovery in these animals, verified if the free cell populations were altered by repeated lavage, and compared the results with those obtained after euthanasia. Live animals were intubated orotracheally by direct vision laryngoscopy and lavaged, except for the last BAL which was done on isolated lungs after euthanasia. Each animal was lavaged weekly for 8 weeks: weeks 1–5 lavages were done with 5 aliquots of 2 ml of normal saline, week 6 with 3 aliquots of 1 ml, week 7 with 3 aliquots of 2 ml, and week 8 with 5 aliquots of 2 ml after euthanasia. The first 5 BAL gave similar results in volumes recovered, total number of cells, cell viability and differentials. The total cell yield of lavages 6 and 7 was less than that of the first 5 BAL and BAL 8; cell differentials with these smaller lavages were similar except for the percentage of neutrophils which was slightly higher than with the 10 ml lavage at week 3. The final lavage gave similar results as the first 5 BAL in terms of total cells recovered, cell viability, and differentials. We conclude that repeated BAL is feasible in live guineapigs, and that it gives a similar cells yield as lung lavage obtained after euthanasia.
Computerized ordering of experimental animals and test authorization
Authors: Maerki Ulrich , Walther Albert , Rossbach Walter
Published: June 2007

The authorization procedure required by law in Switzerland and the internal set-up at Roche for acquiring experimental animals has made a computerized system for monitoring authorizations and animal deliveries essential. The INQUIRE software program, which can be run on the central computer, was used to set-up databases with information on all personnel who place orders and perform experiments (PERI), authorization matters (BEWI), orders (ORDR), deliveries (SPED), animal species (SPEC), animal strains (STRE), populations (POPU) and the management of various data (BARA).

The authorizations database (BEWI) permits sequential searches on specific questions. The animals ordered in the ORDR database are constantly updated in BEWI, thus ensuring that the authorized animal quotas are not exceeded. Expiry of an authorization or an unregistered experimenter will come to light in the course of the plausibility study. Through ORDR the experimenter has a good overview of the animals that he has ordered or have been ordered for him, and he can select the most appropriate strain or population for his studies in STRE or POPU, which contain data on the genetic and physiological characteristics as well as the breeding and keeping of all sublines and stocks.

Realization of the IFIS project has made it a simple matter to keep a check on the legal requirements pertaining to animal experimentation and to update the information and evaluate the entire stock of data at any time.
A modified technique for the production of an arterio-venous shunt in sheep, allowing a comparison of biocompatibility of synthetic materials
Authors: Stertmann W. A. , Scheld H. H. , Kubicek J. , Fitz H. , Lukas H. , Schulze H.
Published: June 2007

Polytetrafluorethylene (PTFE) prostheses were implanted in 12 sheep as a shunt between the carotid artery and the jugular vein using an end-to-side anastomosis technique. This technique allows repeated tests of the pharmacological and toxicological safety of artificial kidney units after both single and multiple administration. Further-more, it enables the investigation of detoxification of compounds via dialysis, thus contributing to drug safety.

Implantation of the prosthesis was uncomplicated. Connection to the extracorporeal circulation was achieved via catheters and maintained using a pump with an output of up to 300 ml/min. This enabled maintenance of extracorporeal circulation for several hours without clinical impairment to the animals. The AV-shunts remained functional for between 8 and 253 days (mean 112·3 days).
A method for perfusion of the isolated rabbit liver through the portal vein and the hepatic artery in a recirculating system
Authors: Meijer G. W. , Geelen M. J. H. , Van Herck H. , Mullink J. W. M. A. , Van Zutphen L. F. M. , Beynen A. C.
Published: June 2007

We describe a method for the isolation and recirculating perfusion of rabbit livers. Livers were perfused simultaneously through the portal vein and the hepatic artery. Precise descriptions of the surgical preparation, perfusion apparatus and perfusion method are given. The viability of rabbit livers was assessed with the use of physiological, biochemical and histological parameters. We conclude that the isolated perfused rabbit livers are sufficiently viable to study their short-term metabolism.
A third component causing random variability beside environment and genotype. A reason for the limited success of a 30 year long effort to standardize laboratory animals?
Authors: Gärtner Klaus
Published: June 2007

This paper is a review of experiments, performed in our laboratory during the past 20 years, designed to analyse the significance of different components of random variability in quantitative traits in laboratory rats and mice. Reduction of genetic variability by using inbred strains and reduction of environmental variability by highly standardized husbandry in laboratory animals did not remarkably reduce the range of random variability in quantitative biological traits. Neither did a tremendous increase of the environmental variability (i.e., living in a natural setting) increase it. Therefore, the postnatal environment cannot be that important as the source of random variability.

Utilizing methods established in twin research, only 20–30% of the range of the body weight in inbred mice were directly estimated to be of environmental origin. The remaining 70–80% were due to a third component creating biological random variability, in addition to the genetic and environmental influences. This third component is effective at or before fertilization and may originate from ooplasmic differences. It is the most important component of the phenotypic random variability, fixing its range and dominating the genetic and the environmental component.

The Gaussian distribution of the body weights observed, even in inbred animals, seems to be an arrangement supporting natural selection rather than the consequence of heterogeneous environmental influences. In a group of inbred rats, the males with the highest chance of parenting the next generation were gathered in the central classes of the distribution of the body weight.
Adrenal cortical response in clinically normal dogs before and after adaptation to a housing environment
Authors: Garnier F. , Benoit E. , Virat M. , Ochoa R. , Delatour P.
Published: June 2007

58 dogs (29 males and 29 females) selected as healthy on clinical and biochemical evaluations were subjected to an ACTH adrenal function test 2 days after their admission to a veterinary hospital ( t+0). Basal female serum cortisol concentrations were significantly higher than concentrations in males (77 nmol/l versus 43 nmol/l; P<0·01). Concentrations post stimulation were not statistically different ( P>0·05) between males and females: 306 (±69) nmol/l versus 291 (±73) nmol/l, respectively. Twelve dogs (6 males and 6 females), randomly selected from the 58, were subjected to the same test 5 weeks later ( t+5) and 12 weeks later ( t+12). Basal cortisol concentrations were lower at t+5 or at t+12 than at t+0. Post stimulation mean cortisol concentrations were lower in males than in females at t+5 (162 versus 232 nmol/l; P<0·05) but not at t+0 (262 versus 320 nmol/l; P>0·5) and t+12 (188 versus 233 nmol/l; P>0·05). These findings are indicating an increased susceptibility of bitches to environmental stress.
Directional apraxia: A unitary account of mirror writing following brain injury or as found in normal young children
Authors: Della Sala Sergio , Cubelli Roberto
Published: June 2007

Mirror writing refers to the production of individual letters, whole words or sentences in reverse direction. Unintentional mirror writing has been observed in young children and brain‐damaged people and interpreted as the manifestation of different cognitive impairments. We report on a mirror writing patient following left hemisphere stroke and the mirror writing phenomena in one sample of children learning to write. We propose a unitary account of mirror writing as the unavailability of the appropriate movement direction representation, either because the right configuration has yet to be specified fully (children learning to write) or because of its damage (acquired brain injury). For this reason, we propose that the lack of directional information relevant to writing be labelled ‘directional apraxia’.
Dynamic size‐change of peri‐hand space through tool‐use: Spatial extension or shift of the multi‐sensory area
Authors: Bonifazi S. , Farnè A. , Rinaldesi L. , Làdavas E.
Published: June 2007

Several studies in humans and non‐human primates have shown that tool‐use can expand near peripersonal space (Farnè & Làdavas, 2000;Iriki, Tanaka, & Iwamura, 1996). In humans, the extension of the near peripersonal space is revealed by an increase in the severity of cross‐modal extinction caused by visual stimulation at the distal edge of a rake after its use as a reaching tool. The crucial question addressed here concerns whether the dynamic re‐sizing of the peri‐hand space in humans constitutes a real spatial expansion of visual‐tactile peri‐hand area along the tool axis. Alternatively, it could constitute a shift of the integrative area from the hand towards the distal edge of the tool, or the formation of a novel visual‐tactile integrative area at the same distal location (Holmes, Calvert, & Spence, 2004). We contrasted the alternative predictions made by these hypotheses in a group of RBD patients by probing, at different locations along the tool axis, the changes induced by tool‐use on cross‐modal extinction. By assessing the visual‐tactile extinction near the hand, midway along the tool, and at the distal edge of the tool we found an increase in visual‐tactile extinction after tool‐use both at the middle and the distal location along the tool axis. In contrast, no change intervened at the hand proximity. These findings support the view that the tool‐use dependent re‐mapping of peri‐hand space in humans consists of a continuous elongation of visual‐tactile peri‐hand area from the hand towards the tip of the tool.
Public Satisfaction With Police: Using Procedural Justice to Improve Police Legitimacy
Authors: Hinds Lyn , Murphy Kristina
Published: June 2007

Policing research and theory emphasises the importance of supportive relationships between police and the communities they serve in increasing police effectiveness in reducing crime and disorder. A key reason people support police is that they view police as legitimate. The existing research literature, primarily from the United States, indicates that the most important factor in public assessments of police legitimacy is procedural justice. The present study is the first in an Australian jurisdiction to examine the effect of procedural justice and police legitimacy on public satisfaction with police. Using responses to a large postal survey (n = 2611), findings show that people who believe police use procedural justice when they exercise their authority are more likely to view police as legitimate, and in turn are more satisfied with police services. This study differs to US-based research in the greater importance of people's evaluations of instrumental factors in judgments of police legitimacy. The findings are important as they confirm that people's assessments of fair and effective policing in Australia will be enhanced by policing strategies that emphasise the use of procedural justice in encounters with the public.
Crime Prevention in Australia: Beyond ‘What Works?’
Authors: Cherney Adrian , Sutton Adam
Published: June 2007

Recent decades have seen governments around Australia launch crime prevention policies to much fanfare. Often, however, achievements have fallen well short of expectations. A key problem is that too many attempts to develop and implement crime prevention have not thought through and articulated what relevant strategies might signify and hope to achieve. In the absence of a basic understanding of, and agreement about, the overall enterprise in which central and local players are engaged, program sustainability and drift problems prevail. Attempts to overcome these difficulties simply by maintaining that polices must be based on ‘what works?’ principles are not helpful. This article works through the implications of the above observations for the way crime prevention strategies should be designed and administered. It argues that commitment to flexible problem identification and solving in the context of a clearly articulated crime prevention planning process is critical to success. However, for crime prevention to emerge and be sustained, governments must see it as consisting of a dialogue between central and local levels. This will only be achieved if strategies developed by the centre are informed by, and reaffirm, a clear political vision and sense of mission.
Nominale: flektiert und unflektiert / Nominals: inflected and uninflected
Authors: Fuhrhop Nanna
Published: June 2007

German is, of course, an inflectional language. Some parts of speech are normally inflected: verbs, adjectives, nouns, pronouns and articles, to name the most predominate ones. This introduction asks whether it makes sense to even mention uninflected forms of inflectional word classes. It is a well-known fact that adjectives are only inflected in one special position – as an attribute preceding a noun. In other syntactic functions adjectives are used in their simple form. Verbal infinitives can be described as partly uninflected as they are not inflected for person and number. Finite and infinite forms have totally different syntactic functions: finite verbs are predicates and infinite verbs are everything else. Now we must ask ourselves if we can also find uninflected, i.e. undeclined nouns? We can also find undeclined forms among pronouns and articles. On the other hand, perhaps there are inflected prepositions and conjunctions. This introduction produces more questions than answers, but it presents the framework for the articles found in this volume.
Unflektierte Substantive sind nicht infinit / Uninflected substantives are not infinite
Authors: Thieroff Rolf
Published: June 2007

After a short look on traditional paradigms of the German noun and after a look on paradigms with so-called underspecified forms, this paper first addresses the question of how paradigms of German nouns would look like if periphrastic noun forms (consisting of a determiner and a noun) were taken into consideration. Since nonperiphrastic noun forms co-exist with such hypothesized periphrastic noun forms, the traditional German noun paradigm with 8 positions would have to be enlarged to paradigms with up to 14 different forms, which is considered to be a severe argument against the hypothesis of periphrastic nouns. Next, starting out from the forms of the verb, the notions finite and non-finite are discussed and it is shown that with the verb there are clear formal differences between finite and non-finite forms which correspond to as clear functional differences between these two different sets of forms. As for the adjective, it is shown that, though similar differences are less straightforward than in the verb, a distinction between finite and non-finite forms still could be made. Finally, two different concepts of non-finite nouns are discussed and it is argued that neither concept leads to a convincing notion of non-finite noun. In conclusion, the idea of non-finite nouns is rejected.
Computerlinguistik im Internet / Computer linguistics on the Internet
Authors: Schmitz Ulrich
Published: June 2007

Erwartungsgemäß gehörten ComputerlinguistInnen zu den ersten und aktivsten Wissenschaftlern, die im Web präsent waren. Bis heute verfügen sie über besonders umfangreiche Angebote. Das gilt auch dann, wenn man – wie hier – Computerlinguistik im engeren Sinne versteht als eine gleichermaßen theoretisch wie anwendungstechnisch orientierte Disziplin, die sprachliche Gesetzmäßigkeiten möglichst explizit formulieren will, um auf dieser Grundlage Rechnersysteme zu bauen, die natürliche (menschliche) Sprache analysieren, bearbeiten, ,verstehen‘ und erzeugen können. (Davon zu unterscheiden sind allgemeine computergestützte Werkzeuge für Sprachwissenschaftler wie elektronische Wörterbücher, Online-Korpora und linguistische Lernsoftware; sie wurden in anderen Ausgaben dieser ZGL-Rubrik „Linguistik im Internet“ vorgestellt.) Wegen der großen Menge computer-linguistischer Materialien im WWW konzentriert sich dieser Bericht aufzwei Arten von Wegweisern. Einerseits werden einige ausgewählte einzelne Adressen vorgestellt, die vor allem Germanisten einen gewissen Querschnitt durch die Vielfalt des Angebots geben mögen. Andererseits werden besonders ergiebige Linklisten genannt, über die man die zahlreichen und vielfältigen Angebote zur CL im Netz bestens erschließen kann.
Predictive Morphometric Relationships for Estimating Fecundity of Sea Lampreys from Lake Champlain and Other Landlocked Populations
Authors: Smith Stephen J. , Marsden J. Ellen
Published: June 2007

Landlocked populations of sea lamprey Petromyzon marinus are a nuisance in the Great Lakes and other lakes in the northeastern United States. In an effort to optimize control efforts, recent research has focused on creating population models to test various control scenarios. Accurate population parameters, such as fecundity, are an important component of these models. To determine the fecundity of sea lampreys in Lake Champlain, we sampled 29 female sea lampreys (mean length = 456 mm [range = 364–550 mm]; mean total wet weight = 173.8 g [range = 96.5–321.4 g]). The estimated fecundity of our sample was 67,660 ± 6,870 eggs/female (95% confidence interval around the mean). To determine the best morphometric indices to estimate fecundity, we examined the relationships between fecundity and length, weight, length and gonadosomatic index (GSI), weight and GSI, and several additional morphological measures. Regression analyses were also conducted on length, weight, and GSI data from previously published studies on sea lamprey fecundity in other landlocked populations. The wet weight of the female was a significant predictor of fecundity in all cases. The predictive ability of a model based on wet weight was improved with the addition of GSI. The addition of nine other morphometric measures did not improve the fit of the model based on wet weight alone.
The Sandbar Shark Summer Nursery within Bays and Lagoons of the Eastern Shore of Virginia
Authors: Conrath Christina L. , Musick John A.
Published: June 2007

We sought to examine the spatial use of coastal bays and lagoons associated with the Eastern Shore of Virginia (i.e., the Atlantic shoreline north of the mouth of the Chesapeake Bay) as nursery habitat for sandbar sharks Carcharhinus plumbeus. Generalized linear mixed models were used to examine the relationship between physical factors and the abundance of neonate and juvenile sandbar sharks within the study area. Neonates, small juveniles, and large juveniles were present throughout the sampling area in relatively high abundance throughout the months of June‐September. Abundances of neonates and small juveniles were correlated with sampling distance from the inlet; larger fractions of these groups were captured as distance from the inlet increased. Large‐juvenile abundance was not significantly correlated with any physical factor. The catch rates of neonate and juvenile sandbar sharks within this area were comparable with those observed in nearby Chesapeake Bay, although a larger number of juveniles greater than 100 cm total length were caught within the Eastern Shore lagoons. The bays and lagoons we examined function as an important primary and secondary nursery ground for this species and fit the criteria to be included in future management measures as a habitat area of particular concern.
NATURAL DISTURBANCES AND DIRECTIONAL REPLACEMENT OF SPECIES
Authors: Platt William J. , Connell Joseph H.
Published: June 2007

The original concept of succession emphasized directional changes in species composition occurring over time on “blank slates” (new substrates or those that followed catastrophic disturbances). In this paper, we explore relationships between different effects of disturbances on residents and the initiation of directional species replacement on sites in a landscape. We present a conceptual model involving recurrent natural disturbances of sites in a landscape containing two species, one of which arrives at sites early and the other arrives late following disturbance. We predict effects of recurrent catastrophic disturbances (no survivors) and non‐catastrophic disturbances (some survivors) on the initiation of directional species replacement, assuming temporal gradients in environmental conditions on sites after disturbance. We predict that directional species replacement will be initiated by catastrophic disturbances, and by non‐catastrophic disturbances when the early species does not survive, but reinvades. Most natural disturbances tend to leave survivors and do not remove early species preferentially. As a result, many post‐disturbance changes are possible on sites; directional species replacement is only one change, and often may not be the most common. One important consequence of the low likelihood that disturbances will initiate directional species replacements should be the precarious existence of early species dependent on disturbances that open sites for colonization. We examined constraints on disturbances, sites, and life histories that might increase colonization by early species. We explored how refuges and life history characteristics might reduce the likelihood of replacement of early species by late species, and we consider how spatial and temporal variation in disturbance effects might influence persistence of early species. In this way, we propose relationships between effects of non‐catastrophic disturbance and the dynamic relationships between species that may be applicable across different ecological systems.

Corresponding Editor: S. T. Jackson
MARINE RESERVES: RATES AND PATTERNS OF RECOVERY AND DECLINE OF PREDATORY FISH, 1983–2000
Authors: Russ Garry R. , Alcala Angel C.
Published: June 2007

The application of no‐take marine‐reserve status to an area is expected to increase spawning‐stock biomass of species targeted by fisheries, and to help sustain fisheries external to the reserve. However, empirical evidence on rates and patterns of increase of density and biomass of target species following closures to fishing, and of decrease when reserve status is removed, remains rare. We have monitored density and biomass of large predatory coral‐reef fish (Serranidae [Epinephelinae], Lutjanidae, Lethrinidae, and Carangidae, as a group) visually in two small no‐take marine reserves and at two control (open to fishing) sites in the Philippines from 1983 to 2000. At Sumilon reserve a complex history of management allowed 13 measurements of density and biomass at durations of reserve protection of −3 yr (i.e., fished for 3 years after reserve status removed) to 9 yr. At Apo reserve 13 measurements were taken at durations of protection of 1–18 yr. We recorded 11 significant (P < 0.05) changes in density at the four sites over the 17 years, three declines and eight increases. All three significant declines occurred when reserve protection was removed. Four of the eight significant increases occurred when reserve status was applied. This represents some of the best evidence currently available that application of marine‐reserve status causes increases in abundance of target species. Three of the four significant increases in density required 4–6 yr of protection. Significant positive linear correlations of mean density of large predators against years of reserve protection were observed at both reserves. The pattern of increase of mean biomass against years of reserve protection was exponential, with biomass initially increasing more slowly than density. Density and biomass increased by factors of 12.2 and 17.3, respectively, during 18 yr of continuous protection in Apo reserve. At Sumilon Island three bouts of unregulated fishing of 1.5–3 yr duration eliminated density and biomass gains accumulated over 5–9 yr of marine reserve protection.
USING LARVAL TREMATODES THAT PARASITIZE SNAILS TO EVALUATE A SALTMARSH RESTORATION PROJECT
Authors: Huspeni Todd C. , Lafferty Kevin D.
Published: June 2007

We conducted a Before‐After‐Control‐Impact (BACI) study using larval digeneans infecting the California horn snail,Cerithidea californica, to evaluate the success of an ecological restoration project at Carpinteria Salt Marsh in California, USA. Digenean trematodes are parasites with complex life cycles requiring birds and other vertebrates as final hosts. We tested two hypotheses for prevalence and species richness of larval trematodes inC. californica: (1) prior to the restoration, sites to be restored would have lower trematode prevalence and species richness relative to unimpacted control sites, and (2) that these differences would diminish after restoration. The sites to be restored were initially degraded for trematode species. They had a mean trematode prevalence (12%) and species richness (4.5 species) that were lower than control sites (28% trematode prevalence and 7 species). Despite the differences in prevalence, the proportional representation of each trematode species in the total community was similar between sites to be restored and control sites. Over the six years following restoration, trematode prevalence nearly quadrupled at restored sites (43%) while the prevalence at control sites (26%) remained unchanged. In addition, species richness at restored sites doubled (9 species), while species richness at the control sites (7.8 species) did not change. Immediately after restoration, the relative abundance of trematode species using fishes as second intermediate hosts declined while those using molluscs as second intermediate hosts increased. Trematode communities at restored and control sites gradually returned to being similar. We interpret the increase in trematode prevalence and species richness at restored sites to be a direct consequence of changes in bird use of the restored habitat. This study demonstrates a new comparative technique for assessing wetlands, and while it does not supplant biotic surveys, it informs such taxonomic lists. Most importantly, it provides a synthetic quantification of the linkages among species in wetland food webs.
POLLUTION‐INDUCED NUTRITIONAL STRESS IN BIRDS: AN EXPERIMENTAL STUDY OF DIRECT AND INDIRECT EFFECTS
Authors: Eeva Tapio , Lehikoinen Esa , Nikinmaa Mikko
Published: June 2007

We tested the hypothesis that pollution‐related reduction in the amount of invertebrate food would explain the lower breeding success of an insectivorous bird, the Great Tit (Parus major), around a point source of heavy metals (copper smelter), where invertebrate densities are known to be depressed. We provided additional food (mealworms and fat) to randomly selected territories near the smelter (<2 km, polluted area) and in the more distant sites (>4 km, control area). Additional food resulted in higher nestling growth and survival in both areas. Exposure of nestlings to heavy metals was estimated by measuring fecal concentrations of copper and lead. In the polluted area, extra food benefited most those broods that would have accumulated the highest lead concentrations. Nestlings in the polluted area exhibited higher asymmetry of primaries, suggesting that they experienced higher stress, but stress hormone (corticosterone) concentrations and metabolic rates (oxygen consumption) did not differ between the polluted and control areas. Contrary to our expectation, the positive effect of additional food on breeding success was greater in the unpolluted area. The results suggest that different amounts of invertebrate food (biomass) in the two areas cannot wholly explain differences in the breeding success of P. major.
A BEHAVIORAL MODEL OF LANDSCAPE CHANGE IN THE AMAZON BASIN: THE COLONIST CASE
Authors: Walker Robert , Drzyzga Scott A. , Li Yali , Qi Jiaguo , Caldas Marcellus , Arima Eugenio , Vergara Dante
Published: June 2007

This paper presents the prototype of a predictive model capable of describing both magnitudes of deforestation and its spatial articulation into patterns of forest fragmentation. In a departure from other landscape models, it establishes an explicit behavioral foundation for algorithm development, predicated on notions of the peasant economy and on household production theory. It takes a “bottom‐up” approach, generating the process of land‐cover change occurring at lot level together with the geography of a transportation system to describe regional landscape change. In other words, it translates the decentralized decisions of individual households into a collective, spatial impact. In so doing, the model unites the richness of survey research on farm households with the analytical rigor of spatial analysis enabled by geographic information systems (GIS). The paper describes earlier efforts at spatial modeling, provides a critique of the so‐called spatially explicit model, and elaborates a behavioral foundation by considering farm practices of colonists in the Amazon basin. It then uses insight from the behavioral statement to motivate a GIS‐based model architecture. The model is implemented for a long‐standing colonization frontier in the eastern sector of the basin, along the Trans‐Amazon Highway in the State of Pará, Brazil. Results are subjected to both sensitivity analysis and error assessment, and suggestions are made about how the model could be improved.
MODELING BIOMASS BURNING EMISSIONS FOR AMAZON FOREST AND PASTURES IN RONDÔNIA, BRAZIL
Authors: Guild Liane S. , Kauffman J. Boone , Cohen Warren B. , Hlavka Christine A. , Ward Darold E.
Published: June 2007

As a source of atmospheric carbon, biomass burning emissions associated with deforestation in the Amazon are globally significant. Once deforested, these lands continue to be sources of substantial burning emissions for many years due to frequent pasture burning. The objective of this research was to quantify biomass‐burning emissions at a local scale. We estimated carbon emissions from three sources: fires associated with primary forest slash, regenerating forest slash, and pastures. The study was conducted on a 94 370‐ha section of land surrounding Jamari, Rondônia, Brazil. In the emissions computation, we integrated site‐specific, ground‐based data (biomass, emission factors for flaming and smoldering combustion, and combustion factors for land‐cover types) with a Landsat TM land cover change map of the study area for 1984–1992. This map was used to ascertain changes in land cover based on TM image dates during a period of early colonization and rapid deforestation in Rondônia. Emissions of CO, CO2, CH4, and other hydrocarbon trace gases were calculated. Between 1984 and 1992, we found CO2 emissions generated by primary forest slash burning were 694 379 Mg C (920 kg C·ha−1·yr−1) and regenerating forest slash burning contributed 23 436 Mg C (31 kg C·ha−1·yr−1), whereas cumulative pasture burning produced 238 180 Mg C (316 kg C·ha−1·yr−1). CO and CH4 followed the same trends by land cover type. Primary forest slash burns contributed 73% of the total C emissions whereas burning regenerating forest slash and pasture produced 2% and 25%, respectively. The major finding of this work is the identification of pasture burning as a potentially important source of pyrogenic emissions, but better data on biomass and combustion efficiency could confirm this finding. Further we demonstrated a novel method for estimating area burned that links land cover type and change to burn frequency.
RIVERINE ORGANIC MATTER COMPOSITION AS A FUNCTION OF LAND USE CHANGES, SOUTHWEST AMAZON
Authors: Bernardes Marcelo C. , Martinelli Luiz A. , Krusche Alex V. , Gudeman Jack , Moreira Marcelo , Victoria Reynaldo L. , Ometto Jean P. H. B. , Ballester Maria V. R. , Aufdenkampe Anthony K. , Richey Jeffrey E. , Hedges John I.
Published: June 2007

We investigated the forms and composition of dissolved and particulate organic matter in rivers of the Ji‐Paraná Basin, which is situated at the southern limit of the Amazon lowlands and has experienced extensive deforestation in the last three decades (∼35 000 km2). Our objective was to investigate how extensive land‐use changes, from forest to cattle pasture, have affected river biogeochemistry. We measured a series of chemical, biochemical, and isotopic tracers in three size classes of organic matter within five sites along Ji‐Paraná River and eight more sites in six tributaries. The results were compared with C4 leaf and pasture soils end members in order to test for a pasture‐derived signal in the riverine organic matter. The coarse size fraction was least degraded and derived primarily from fresh leaves in lowland forests. The fine fraction was mostly associated with a mineral soil phase, but its ultimate source appeared to be leaves from forests; this fraction was the most enriched in nitrogen. The ultrafiltered dissolved organic matter (UDOM) appeared to have the same source as the coarse fraction, but it was the most extensively degraded of the three fractions. In contrast to Amazon white‐water rivers, rivers of the Ji‐Paraná Basin had lower concentrations of suspended solids with a higher carbon and nitrogen content in the three size fractions. However, principal component analyses showed a correlation between areas covered with pasture and the δ13C values of the three size fractions. The highest δ13C values were observed in the ultrafiltered dissolved organic matter of the Rolim‐de‐Moura and Jarú rivers, which have the highest areas covered with pasture. The lower the order of the streams and the higher the pasture area, the greater is the possibility that the C4‐derived organic matter signal will be detected first in the faster‐cycling fraction (UDOM). The large change in land use in the Ji‐Paraná Basin, replacement of primary forests by C4 pastures for cattle feeding, that has taken place in the last 30–40 yr, has already changed the characteristics of the composition of the riverine organic matter.
TREE AGE ESTIMATION FOR THE TROPICS: A TEST FROM THE SOUTHERN APPALACHIANS
Authors: Baker Patrick J.
Published: June 2007

The lack of annual growth rings in the majority of tropical tree species greatly limits our understanding of the long‐term dynamics of tropical forests. To address this problem, several methods have been developed to estimate the age of tropical trees from diameter growth data. These past approaches, however, suffer from two major flaws: (1) they assume a deterministic age–size relationship for a tree species, and (2) they have not been verified with independently derived age data. In this paper, I present a new approach that uses diameter growth rates, independent of tree size, that are stratified by crown class to estimate the age of individual trees. Past approaches have assumed that when present‐day canopy trees were juveniles they grew at rates similar to conspecifics currently in the understory. In contrast, the crown class model assumes that present‐day canopy trees have grown at rates similar to conspecifics in the same crown class, irrespective of size, throughout ontogeny.

The crown class model was compared to a periodic annual increment (PAI) model typical of past approaches in mixed oak‐hardwood forest in the southern Appalachians, USA. Tree ages were obtained independently from tree cores from three stands of differing age structure. Comparisons between the two models were made for species' population age structures (independent of stands) and stand age structures (independent of species).

Age estimation errors for the crown class model were lowest for relatively shade‐intolerant species such as yellow poplar (Liriodendron tulipifera) and chestnut oak (Quercus prinus), but increased with the increasing shade tolerance of the species. The PAI model followed the opposite pattern, providing the most accurate age estimates for shade‐tolerant species. These results were consistent with the underlying ecological assumptions of each model.

When predicted age distributions for individual stands were compared to the true age distributions, the PAI approach had higher estimation errors than the crown class model in almost every case. In addition, the PAI model had a strong tendency to overestimate tree ages. A mixed model that used crown class age estimates for shade‐intolerant species and PAI model age estimates for shade‐tolerant species generated the most accurate estimates of stand age distribution. The results of this study suggest new opportunities for the study of long‐term dynamics in tropical forests and underscore the importance and utility of validating models with independent data.
EVALUATING THE IMPACT OF POLICY OPTIONS ON AGRICULTURAL LANDSCAPES: AN ALTERNATIVE‐FUTURES APPROACH
Authors: Berger Patricia A. , Bolte John P.
Published: June 2007

Alternative‐futures analysis was used to analyze different scenarios of future growth patterns and attendant resource allocations on the agricultural system of Oregon's Willamette River Basin. A stakeholder group formulated three policy alternatives: a continuation of current trends, an increased reliance on market forces to determine land use, and an increased emphasis on environmental restoration programs. To model the alternative scenarios first required the development of a spatial representation of the current agricultural system. Next, rules and constraints based on the three policy scenarios were formulated. Then a spatially explicit, multi‐attribute, decision‐making model was used to model changes in agricultural land cover and land use. This procedure generated three future landscapes, each depicting an alternative state of the agricultural system in the year 2050. Finally, the agronomic and environmental condition of each agricultural system was evaluated by using landscape metrics and screening models. The results show that the type and amount of farmland conversion were the scenario elements that most distinguished the future agricultural landscapes. By continuing current land use policies, nearly all of the existing farmland was conserved for future agricultural use, while both the market‐driven and environmental restoration scenarios converted 15% or more of the agricultural land to other uses. The use of farmland for vegetation restoration activities was particularly successful in improving riparian habitat, while habitat quality over the region showed widespread improvement. The patterns of crop selection in each future followed general trends, but with variations among scenarios as crop selection decisions adapted to changing field and basin conditions.
LITTER INVERTEBRATE RESPONSES TO VARIABLE DENSITY THINNING IN WESTERN WASHINGTON FOREST
Authors: Schowalter T. D. , Zhang Y. L. , Rykken J. J.
Published: June 2007

We evaluated the response of forest floor invertebrates to variable density thinning (VDT) of the Douglas‐fir (Pseudotsuga menziesii(Mirb.) Franco) forest overstory at Ft. Lewis, Washington, during 2000 and 2001 (7–8 years post‐thinning). We placed pitfall traps at 8–12 random grid points in each of four thinned units and four control (unthinned) units in each of two sites (blocks) representing different management histories. Most taxa showed significant seasonal trends, with peak abundances during summer. ANOVA indicated strongly significant effects of site for 9 of 39 species and combined taxa, probably reflecting factors associated with management history; only two taxa showed significant responses to the thinning treatment or to block × treatment interactions. Indicator analysis revealed three spider species as potential indicators of thinning treatment. Detrended correspondence analysis (DCA) and cluster analysis for 85 species indicated that the thinning treatments altered the invertebrate assemblage in different ways, depending on initial structure. Multiresponse permutation procedure (MRPP) confirmed that species assemblages, but not combined taxa or functional groups, in treated units differed significantly from those in control units and from each other. Therefore, VDT affected forest floor invertebrates in the short term, but the effect was strongly modified by site (block) factors, especially management history. These results indicated that previous management history is an important determinant of treatment effect and that compensatory shifts in relative importance among species within functional groups may maintain ecological function during environmental changes.
VARIABILITY AND DYNAMICS OF A DESERT STREAM COMMUNITY
Authors: Eby Lisa A. , Fagan William F. , Minckley Wendell L.
Published: June 2007

Communities can be highly variable over a few years, but remain fairly constant over the long term. Evaluating measures and examining the variability associated with long‐term change is useful because it increases our understanding of and our ability to predict responses to disturbances. We used long‐term fish community data from Aravaipa Creek, Arizona, USA, a Sonoran Desert stream, to determine whether there had been long‐term changes in the community composition, what measures best describe these shifts, and what environmental factors are correlated with the changes. Aravaipa Creek is an intrinsically variable system and one of the few remaining desert streams to support its complete historical assemblage of native fishes. Multivariate analyses illustrated important changes in composition of the native fish community that were not described by traditional measures of persistence and stability. In the early 1980s, changes in community composition were correlated with alterations in base flow, while more recent changes are likely associated with the presence of exotic species. Changes in stream morphology, hydrology, and climate have decreased flow variability, thereby increasing the likelihood of exotic establishment, and may have increased the downstream connection between Aravaipa Creek and the San Pedro River thus increasing the likelihood of repeated invasions by nonnative species. These results support previous research in intrinsically variable desert systems, which conclude that retention of high flow variability is important to conservation of the native fish community. In addition, although connectivity in aquatic lotic systems is important, isolation from large river systems teaming with exotics may be important in preserving these remnant native fish assemblages.
ASSESSING RARITY OF SPECIES WITH LOW DETECTABILITY: LICHENS IN PACIFIC NORTHWEST FORESTS
Authors: Edwards Thomas C. , Cutler D. Richard , Geiser Linda , Alegria Jim , McKenzie Dan
Published: June 2007

We show how simple statistical analyses of systematically collected inventory data can be used to provide reliable information about the distribution and habitat associations of rare species. Using an existing design‐based sampling grid on which epiphytic macrolichens had been inventoried in the Northwest Forest Plan area of the U.S. Pacific Northwest, we (1) estimate frequencies and standard errors for each of 25 lichen species having special management designation (i.e., Survey and Manage), (2) assess the probability that individual species were associated with specific land allocation and forest stand age classifications, and (3) provide estimates of sample sizes necessary to ensure sufficient detections for these analyses. We conclude with a discussion of management and conservation information needs that extant data can satisfy and identify advantages and limitations of random vs. nonrandom sampling strategies. Combining design‐assisted and model‐assisted approaches can overcome some of the limitations of either single strategy.