Size classes and major taxonomic groups of phytoplankton at two locations in the subarctic pacific ocean in May and August, 1984

In order to assess the relative importance of the pico- and nanoplankton fractions, the composition of entire phytoplankton communities at Weathership Station P (50°N; 145°W) and at 53°N; 145°W were studied in May and August, 1984, using epifluorescence, scanning electron, and inverted light microscopy. The biomass of major taxa within five size classes was estimated from cell volume and cell concentration. For both months, approximately twothirds of the total phytoplankton carbon were contributed by cells<5 m. In May, 16% of plant biomass was contributed by cells<2 m, and in August 39%. (In both months 90% of plant carbon<2 m was contributed by the bluegreen coccoid Synechococcus spp.) Cells 2 to 5 m contributed about 39% to total plant carbon; they were mostly flagellates in May and nonmotile coccoids in August. The remaining one-third of algal carbon was composed of dinoflagellates, cryptomonads, other flagellates and diatoms, all >5 m. Very little difference between taxa was observed with respect to vertical stratification. Small taxonomic changes were observed in the community between May and August, and within each month.Contribution No. 1694 of the School of Oceanography, University of Washington, Seattle, Washington 98195, USA     

Multi-decadal drought and amplified moisture variability drove rapid forest community change in a humid region

Climate variability, particularly the frequency of extreme events, is likely to increase in the coming decades, with poorly understood consequences for terrestrial ecosystems. Hydroclimatic variations of the Medieval Climate Anomaly (MCA) provide a setting for studying ecological responses to recent climate variability at magnitudes and timescales comparable to expectations of coming centuries. We examined forest response to the MCA in the humid western Great Lakes region of North America, using proxy records of vegetation, fire, and hydroclimate. Multi-decadal moisture variability during the MCA was associated with a widespread, episodic decline in Fagus grandifolia (beech) populations. Spatial patterns of drought and forest changes were coherent, with beech declining only in areas where proxy-climate records indicate that severe MCA droughts occurred. The occurrence of widespread, drought-induced ecological changes in the Great Lakes region indicates that ecosystems in humid regions are vulnerable to rapid changes in drought magnitude and frequency.     

Ontogeny of space use and diet of two temperate damselfish species, <Emphasis Type="Italic">Parma microlepis</Emphasis> and <Emphasis Type="Italic">Parma unifasciata</Emphasis>

Studies of reef fish herbivory have mainly focused on the impacts and behaviour of adults of tropical species. In this study, the ontogenetic shifts in home range, aggression, feeding rate, diet and gut morphology in juveniles and adults of two temperate territorial damselfishes, Parma microlepis and Parma unifasciata, were determined. Both P. microlepis and P. unifasciata juveniles under 80 mm TL exhibited no aggressive chases towards conspecifics or other species, while above 80 mm TL aggressive chase frequency increased in conjunction with an increase in home range, defended as a territory. Ontogenetic diet shifts, characterised by an increase in herbivory (P. unifasciata: juveniles: 64% plant material, adults: 95% plant material; P. microlepis: juveniles: 43% plant material, adults: 67% plant material) were observed for both species. The ratio of digestive tract length to body length, which often accompanies a switch to herbivory, increased significantly with ontogeny for both species. Compared to tropical confamilial grazers, these temperate damselfish species feeding rates were lower, and they had larger territories which were not as strongly defended (fewer aggressive chases).     

Measuring Plant Cover in Sagebrush Steppe Rangelands: A Comparison of Methods

Methods that are more cost-effective and objective are needed to detect important vegetation change within acceptable error rates. The objective of this research was to compare visual estimation to three new methods for determining vegetation cover in the sagebrush steppe. Fourteen management units at the US Sheep Experiment Station were identified for study. In each unit, 20 data collection points were selected for measuring plant cover using visual estimation, laser-point frame (LPF), 2 m above-ground-level (AGL) digital imagery, and 100-m AGL digital imagery. In 11 of 14 management units, determinations of vegetation cover differed (P < 0.05). However, when combined, overall determinations of vegetation cover did not differ. Standard deviation, corrected sums of squares, coefficient of variation, and standard error for the 100 m AGL method were half as large as for the LPF and less than the 2-m AGL and visual estimate. For the purpose of measuring plant cover, all three new methods are as good as or better than visual estimation for speed, standard deviation, and cost. The acquisition of a permanent image of a location is an important advantage of the 2 and 100 m AGL methods because vegetation can be reanalyzed using improved software or to answer different questions, and changes in vegetation over time can be more accurately determined. The reduction in cost per sample, the increased speed of sampling, and the smaller standard deviation associated with the 100-m AGL digital imagery are compelling arguments for adopting this vegetation sampling method.     

Shifting drivers and static baselines in environmental governance: challenges for improving and proving water quality outcomes

Understanding the conditions that enable or constrain success in environmental governance is crucial for developing effective interventions and adapting approaches. Efforts to achieve and assess success in environmental quality improvement are often impeded by changes in conditions that drive outcomes but lie outside the scope of intervention and monitoring. We document how long-term changes in land use, agriculture, and climate act as non-stationary, shifting drivers of change that combine to render water quality management interventions less effective and increasingly difficult to assess. Focusing on the Yahara River watershed of south-central Wisconsin, USA, we ask how baselines influence program modeling, monitoring, and evaluation, as well as adaptation in governance approach. Through historical trend, GIS, and policy and qualitative data analyses, we find that changes in long-term land use and precipitation pattern dynamics exert tremendous pressure on water quality outcomes but are not captured in snapshot baseline assessments used in management planning or evaluation. Specifically, agricultural sector change related to the intensification of milk and manure production is increasingly challenging to address through best management practices, and flashier precipitation associated with climate change makes it difficult to achieve goals and establish a causal connection between management interventions and outcomes. Analysis of shifting drivers demonstrates challenges facing environmental governance in the context of climatic and social–ecological change. We suggest that goal setting, program design, and evaluation incorporate new modes of analysis that address slowly changing and external determinants of success.     

An environmental justice analysis of caribou recovery planning, protection of an Indigenous culture, and coal mining development in northeast British Columbia, Canada

Environmental justice theory postulates that communities that predominately consist of minorities and those of a lower socioeconomic status are compelled to bear a disproportionate distribution of burdens resulting from land use decisions. In this article, we present a case study of West Moberly First Nations (an Indigenous group) in British Columbia, Canada, and their fight to protect a threatened herd of caribou from coal mining activities. We examine the role of caribou in maintaining the First Nations’ cultural integrity and the adverse effects of several decisions made by the Provincial Government of British Columbia that would allow a mining company to destroy the critical habitat of the species. Analysis shows that the decisions negate federal law, disregard the best available scientific and traditional knowledge, and fail to uphold the constitutional and treaty rights of the First Nation to meaningfully exercise its cultural practices and customs. A disproportionate share of environmental burdens was therefore placed onto the shoulders of the First Nation while the interests of the government and the mining industry were protected. We conclude that the decisions are a clear case of intentional environmental injustice on the part of the British Columbia government.     

Ground-Cover Measurements: Assessing Correlation Among Aerial and Ground-Based Methods

Wyoming’s Green Mountain Common Allotment is public land providing livestock forage, wildlife habitat, and unfenced solitude, amid other ecological services. It is also the center of ongoing debate over USDI Bureau of Land Management’s (BLM) adjudication of land uses. Monitoring resource use is a BLM responsibility, but conventional monitoring is inadequate for the vast areas encompassed in this and other public-land units. New monitoring methods are needed that will reduce monitoring costs. An understanding of data-set relationships among old and new methods is also needed. This study compared two conventional methods with two remote sensing methods using images captured from two meters and 100 meters above ground level from a camera stand (a ground, image-based method) and a light airplane (an aerial, image-based method). Image analysis used SamplePoint or VegMeasure software. Aerial methods allowed for increased sampling intensity at low cost relative to the time and travel required by ground methods. Costs to acquire the aerial imagery and measure ground cover on 162 aerial samples representing 9000 ha were less than $3000. The four highest correlations among data sets for bare ground—the ground-cover characteristic yielding the highest correlations (r)—ranged from 0.76 to 0.85 and included ground with ground, ground with aerial, and aerial with aerial data-set associations. We conclude that our aerial surveys are a cost-effective monitoring method, that ground with aerial data-set correlations can be equal to, or greater than those among ground-based data sets, and that bare ground should continue to be investigated and tested for use as a key indicator of rangeland health.     

Using PERT methodology in nuclear material safeguards and chemical process control

The loss of nuclear material into the environment by leakage or theft is a serious problem. The same is true for the loss of chemical reagents from a chemical production or purification process. The present article shows how the Program Evaluation and Review Technique (PERT) can be used by a facility manager to deal with these problems. It also provides a way to look at the overall production process rather than just at individual material balance areas, as has often been the case in the past.     

Monitoring Urban Streams: Strategies and Protocols for Humid-Region Lowland Systems

Governmental mandates and public awareness have forcedprogressively smaller and less sophisticated agencies andorganizations to initiate stream monitoring programs,particularly in urban and urbanizing areas. Yet many of thesemonitoring efforts lack either a coherent conceptual frameworkor appropriately chosen methods, and they rely on monitoringtechniques that are simply infeasible for these institutionalsettings. We propose a monitoring strategy, and specificexisting monitoring protocols, that will be useful for themanagement and rehabilitation of streams in urbanizing watersheds.A monitoring strategy must be developed by 1) identifying the management question(s) being addressed, 2) determining theinstitional level of effort required (and available) toeffectively make particular kinds of measurements, and 3) identifying what specific parameters should and can be measured.Only a limited set of parameters show much utility orfeasibility in addressing the most common management questionsbeing faced by municipalities in urbanizing, humid-area regionsof the United States. These include measures of riparian canopy,bank erosion and bank hardening, and in-stream large woodydebris. With some additional expertise useful data can also beincluded on channel gradient, substrate composition, and pools.Nearly all of the other myriad parameters that have beenmeasured historically on rivers and streams show little apparentvalue in these watershed and institutional settings.     

Water treatment control using the joint estimation outlier detection method

The loss of contaminated wastewater into the environment by leakage or other means is a serious problem. This problem is essentially the same as true of the loss of chemical reagents from a chemical production or purification process. The present article shows how the joint estimation method, an outlier detection method for time series analysis, can be used by a facility manager to deal with these problems.