Jim A. Perry

Drift and benthic invertebrate responses to stepwise and abrupt increases in non-scouring flow

We conducted two experiments to assess drift and benthic invertebrate responses to stepwise and abrupt changes in non-scouring flow in gravel-bed experimental streams. Intuitively, a stepwise flow increase should allow aquatic invertebrates more time to seek refuges than would an abrupt increase. We hypothesized that abrupt flow increases would result in larger increases in taxon richness and in the number of invertebrates in the drift, and a larger decrease in benthic density than would stepwise flow increases. Two kinds of drift response to flow increases were observed in the stepwise experiment: (1) no response (e.g. Caenissp. [Ephemeroptera] and Sphaeriidae [Pelecypoda]); (2) threshold response of some aquatic (e.g. Crangonyx pseudogracilis[Amphipoda]) and semiaquatic (e.g. Ormosiasp. [Diptera]) taxa. Drift richness and drift density in both experiments declined after reaching a peak. The peak was reached almost immediately in the abrupt treatment and later in the stepwise treatment. Maximum richness of taxa and taxon composition in the drift were similar in both experiments. Despite significant increases in drift, stepwise and abrupt increases in flow did not have a significant effect on benthic density. However, relative to reference streams, the percentage of total benthic invertebrates in the drift increased 10× in the stepwise experiment and 33× in the abrupt experiment. These non-scouring increases in flow were non-trivial. Our results suggest that several high flow events of the same magnitude (i.e. 2.5–3.0 fold increases) may cause considerable losses of benthic populations to the drift. The rate of increases in flow appears to be important: abrupt increases in flow had a stronger effect on invertebrate drift than did stepwise increases.

Relation of Instream Habitat and Physical Conditions to Fish Communities of Agricultural Streams in the Northern Midwest

Abstract Fish, instream habitat, and physical stream conditions were surveyed in 29 agricultural streams in the Red River of the North basin during summer 1994 and the Minnesota River basin during summer 1997. Our goal was to determine which instream habitat and physical conditions should be considered for stream restoration. Principle components analysis identified six axes that explained 79% of the total variability in instream habitat and physical conditions. Percent run, percent boulder, percent woody debris, percent overhanging vegetation, percent sand, and frequency of erosion were the variables best associated with these axes. Multiple linear regression analysis of the instream habitat and physical conditions explained 14–50% of the variability in fish community composition. Managers of agricultural warmwater streams in the northern Midwest should emphasize these six instream habitat and physical conditions, and the factors that influence them, during stream restoration.

Management of diffuse pollution in agricultural watersheds : Lessons from the Minnesota river basin

The Minnesota River (Minnesota, USA) receives large non-point source pollutant loads. Complex interactions between agricultural, state agency, environmental groups, and issues of scale make watershed management difficult. Subdividing the basins 12 major watersheds into agro-ecoregions based on soil type, geology, steepness, and climate enhances predictability of stream water quality parameters. An eight-step framework for agricultural watershed management is presented.

The environmental audit. I. Concepts

Extensive criticism of water quality monitoring programs has developed as costs are compared with the benefits produced by monitoring efforts. Collecting water quality data while developing understanding of the functional character of the environment will improve water quality monitoring data utility in environmental management. The “environmental audit” characterizes the attributes of the natural environment (that is, attribute type, intensity, and variability), providing a theoretical as well as practical foundation for data interpretation. In the view proposed here, traditional monitoring means the very narrow activity of collecting samples and perhaps analyzing them and storing the analyses. In the environmental audit, these activities are a mechanism to systematically improve environmental monitoring and assessment by improving the design and implementation of environmental programs. Major reasons why existing programs fail to meet the needs of legislators, regulators, and conservationists are identified.

World Heritage hot spots: a global model identifies the 16 natural heritage properties on the World Heritage List most at risk from climate change

UNESCO’s 207 natural heritage World Heritage Properties are at risk from climate change, but risk varies widely among properties. I offer a global model based on multi-model general circulation model (GCM) ensembles, vulnerability and Human Influence (HII), producing the World Heritage Vulnerability Index (WHVI), a measure of relative risk among properties. Nineteen properties are most at risk (i.e. WHVI > mean + 1 SD). Those include islands (i.e. Vallée de Mai, Aldabra, East Rennell, Teide, Laurisilva of Maderia, Isole Eloie, Pitons Management Area, Morne Trois Pitons and Galapagos Islands), coastal properties (i.e. Everglades, Desembarco del Granma, High Coast and Kvarken Archipelago, Doñana, Brazilian Atlantic Islands, Ichkeul and the Sunderbans) and mountainous properties (i.e. the Pyrenees Mont Pérdu, Nanda Devi and the Valley of Flowers, and Mount Kinabalu). Three properties (i.e. Teide, Isole Eloie and the Pitons Management Area) are geologic, apparently relatively resistant to short-term climactic changes. The remaining 16 are likely to respond to climactic changes in the next 40 years; those changes may threaten their World Heritage status. Those properties are where society could most effectively invest in adaptation. I identify adaptive strategies and next steps for proactive climate change adaptation in the 16 natural heritage properties on the World Heritage List most at risk.

Physical integrity: the missing link in biological monitoring and TMDLs

The Clean Water Act mandates that the chemical, physical, and biological integrity of our nation’s waters be maintained and restored. Physical integrity has often been defined as physical habitat integrity, and as such, data collected during biological monitoring programs focus primarily on habitat quality. However, we argue that channel stability is a more appropriate measure of physical integrity and that channel stability is a foundational element of physical habitat integrity in low-gradient alluvial streams. We highlight assessment tools that could supplement stream assessments and the Total Maximum Daily Load stressor identification process: field surveys of bankfull cross-sections; longitudinal thalweg profiles; particle size distribution; and regionally calibrated, visual, stream stability assessments. Benefits of measuring channel stability include a more informed selection of reference or best attainable stream condition for an Index of Biotic Integrity, establishment of a baseline for monitoring changes in present and future condition, and indication of channel stability for investigations of chemical and biological impairments associated with sediment discontinuity and loss of habitat quality.

Challenges to Using Neem (Azadirachta Indica Var. Sianensis Valenton) in Thailand

The use of botanical insecticides based on the neem seed (Azadirachta indica var.siamensis Valeton) shows strong potential in the fight against important agricultural pests. Unfortunately, its use in rural Thailand is extremely limited. This study examines the efficacy of neem extracts processed under rural conditions; identifies factors that influence local farmers’ adoption of neem products; and proposes recommendations to promote the use of neem insecticides. The principal findings are: in field trials conducted under typical rural conditions, neem did not adequately control major pests of yard-long beans (Vigna sesquipedalis); and intensity of vegetable production, knowledge of neem insecticides and availability and accessibility of neem products strongly influence farmers’ adoption of neem products for pest control.ResumenShows starkes Potential im Kampf gegen wichtige landwirtschaftliche Schädlinge. Leider wird seine Verwendung in ländlichem Thailand sehr beschränkt. Dieses Studium untersucht die Wirksamkeit von neem-Auszügen, die unter ländlichen Bedingungen verarbeitet wird; identifiziert Faktoren, die örtliche Bauern Adoption von neem-Produkten beeinflussen; und schlägt Empfehlungen vor, die Verwendung von neem-Insektengiften zu fördern. Der Haupt Tatbestand ist: in Feld-Versuchen, die unter typischen ländlichen Bedingungen durchgeführt werden, kontrollierten neem keine bedeutende Schädlinge Yard-langer Bohnen hinreichend (Vigna sesquipedalis); und Intensität Pflanzen Produktion, Wissen von neem-Insektengiften und Erhältlichkeit und Zugänglichkeit von neem-Produkten beeinfluβt Bauern stark’ Adoption von neem-Produkten für Schädlingsbekämpfung.

The Dillon Hypothesis of Titular Colonicity: An empirical test from the ecologic

The Dillion Hypothesis of Titular Colonicity has been proposed as the primary correlate of scholarly character in journal publication. The Hypothesis was developed and tested in the fields of education, psychology, and literary criticism; its geographical strengths have been tested in a study of the same fields from New Zealand. In this paper, The Hypothesis is tested across disciplinary lines. Data from 21,000 titles in six journals of ecology and aquatic sciences are examined. Titular colonicity has increased dramatically over the last 15 years. Striking differences are found between theoretical and applied sub‐fields (with theoretical papers being an order of magnitude more scholarly) and between the papers presented at international scientific congresses and those published in peer‐reviewed journals (the latter are more scholarly). No significant differences in scholarly character between aquatic and terrestrial ecology were detectable. A comparison of findings from available studies reveals that more theoretic research in biology is significantly more scholarly than that in psychology. In general, the results of this study support the Dillon Hypothesis of Titular Colonicity.

Survey of state water quality monitoring programs

Budget changes, whether positive or negative, in water quality management agencies often mean a change in resources available for water quality monitoring. Many state agencies are currently facing monitoring budget cuts and, as a result, are reevaluating their monitoring programs. Such evaluations make use of a number of information sources, not the least of which are monitoring activities in other states. This article reports results of a survey of all fifty state water quality monitoring programs. Twenty questions were asked in the general areas of fixed-station monitoring, special studies, and biological monitoring. Each state was contacted by telephone at least twice during the survey. Fixed-station monitoring is conducted by 48 of 50 states. An average of 75 stations per state are sampled, generally on a monthly basis. There is a large variation in the way data are analyzed by the states; water quality indices and plots of concentration or loading over time are the most common methods. All but three states conduct special studies, but only seven repeat the studies on a regular basis. Special studies are generally problem specific as opposed to basin oriented. Biological monitoring is performed by 33 states; however, this is an area in which budget cuts are having a noticeable impact. In some cases, biological monitoring is being completely eliminated or suspended. Macroinvertebrate sampling is performed quarterly to biannualiy by 50% of the states; 75% of the states that sample macroinvertebrates do so annually. Periphyton sampling is performed by 33% of the states. Over 50% of the states are in the process of revising, or have revised, their monitoring program during the past five years. However, only four states had a detailed rationale and operating procedure for the entire monitoring system. Results of the survey are, therefore, averages of existing monitoring programs. Average results do not necessarily represent ideal situations, but do give an indication of how states are coping with their monitoring responsibilities.

The future of heritage as climates change: Loss, adaptation and creativity

In the past decade, the threat of climate change has received increasing attention in official heritage discourse. Holistic studies on the relationship between climate change and heritage are therefore still few and far between. From the vantage point of archaeologists and heritage professionals, David Harvey and Jim Perry’s edited volume, The Future of Heritage as Climates Change: Loss, Adaptation and Creativity, is an essential read that provides an innovative theoretical framework and applied case studies to fill the knowledge gap in understanding this nexus. Rodney Harrison’s (2012) dialogical model of heritage sets the premise for the book; that is, heritage is a dynamic process where cultural and natural processes—or humanity’s impacts on nature and vice versa—are deeply connected and must be understood for successful conservation and reflection of societal values. In this vein, the loss and uncertainty that climate change poses need not be negative, but an element to consider when adapting heritage.