Incorporating connectivity into conservation planning for the optimal representation of multiple species and ecosystem services

Conservation planning tends to focus on protecting species’ ranges or landscape connectivity but seldom both—particularly in the case of diverse taxonomic assemblages and multiple planning goals. Therefore, information on potential trade-offs between maintaining landscape connectivity and achieving other conservation objectives is lacking. We developed an optimization approach to prioritize the maximal protection of species’ ranges, ecosystem types, and forest carbon stocks, while also including habitat connectivity for range-shifting species and dispersal corridors to link protected area. We applied our approach to Sabah, Malaysia, where the state government mandated an increase in protected-area coverage of approximately 305,000 ha but did not specify where new protected areas should be. Compared with a conservation planning approach that did not incorporate the 2 connectivity features, our approach increased the protection of dispersal corridors and elevational connectivity by 13% and 21%, respectively. Coverage of vertebrate and plant species’ ranges and forest types were the same whether connectivity was included or excluded. Our approach protected 2% less forest carbon and 3% less butterfly range than when connectivity features were not included. Hence, the inclusion of connectivity into conservation planning can generate large increases in the protection of landscape connectivity with minimal loss of representation of other conservation targets.     

Book reviews

Earth Politics. Ernst Ulrich von Weizsacker, 1994, London, Zed Books, 234 pp. ISBN 1 85649 174 9, pb £14.95; hb £36.95

Greening Your Local Authority. Janice Morphet (Ed.), 1994, London, Pitman Publishing (originally Harlow, Longman), 144 pp. ISBN 0582 229 065, pb £32.50

Ecology and Society: an introduction. Luke Martell, 1994 London, Polity Press, 250 pp. ISBN 0 7456 1022 6, hb £39.50, ISBN 0 7456 1023 4, pb £11.95

The Politics of the Environment. Robert E. Goodin, 1994. Cheltenham, Edward Elgar, 599 pp. ISBN 1 85278 872 0, hb £115.00

Introduction to Environmental Impact Assessment John Glasson, Riki Therivel &; Andrew Chadwick, 1994, London, UCL Press, 352 pp. ISBN 1 85728 117 9, hb £45.00, ISBN 1 85728 118 7, pb £14.95

Planning for the Planet: sustainable development strategies for local and strategic plans. Friends of the Earth, 1994, London, FoE, 104 pp. ISBN 1 85750 224 8, £12.00

Environmental Strategy and Sustainable Development: the corporate challenge for the 21st century. Richard Welford, 1995, London, Routledge, 240 pp. ISBN 0 415 10551 X, hb £40.00, ISBN 0 415 10552 8, pb £12.99

Housing and the Environment: a new agenda. Mark Bhatti, Jane Brooke &; Mike Gibson (Eds), 1994, Foreword by Jonathon Porritt, Coventry, Chartered Institute of Housing, 210 pp. ISBN 0 901 607 738, £14.95     

Vehicles driven by teenagers in their first year of licensure

OBJECTIVE: to determine access to vehicles, vehicle ownership and its correlates, and types of vehicles driven by teenagers during their first year of licensure. METHODS: About 3,500 Connecticut teenagers and their parents recruited at DMV offices participated in a study aimed at persuading parents to impose and maintain driving restrictions on their sons and daughters. Telephone interviews with teens and parents, which included questions on vehicles driven, were conducted upon licensure and at intervals throughout the year. RESULTS: The majority of both male and female teens owned vehicles immediately upon licensure. Family income and number of vehicles in the family were associated with early ownership. A year later 74% owned vehicles. Small cars, which provide inferior crash protection, were the most popular vehicle; the percent driving small cars increased from 36% to 42% over the year. About 25% were driving SUVs, pickups, or sports cars, which may increase crash risk for young beginners. One year after licensure, only 35% of teens were driving midsize or large passenger cars, the types of vehicles recommended for them, and about one-third of these vehicles were 10 or more years old. Owners were more likely than non-owners to drive older and smaller vehicles, to drive more miles, do more risky driving, and to have more traffic violations and crashes. DISCUSSION: Many teenagers in Connecticut were driving vehicles that rank low in crash protection or may increase crash risk. Attention to the young driver problem has been focused primarily on managing driving risks through graduated licensing systems. More attention needs to be given to the vehicles teens drive, and how decisions about vehicle type and ownership are made. Parents exert control over what vehicles their sons and daughters drive, and may benefit from information on how to make choices that better balance cost, safety, and other factors that go into these decisions.     

Feeding responses to selected alkaloids by gypsy moth larvae, Lymantria dispar (L.)

Deterrent compounds are important in influencing the food selection of many phytophagous insects. Plants containing deterrents, such as alkaloids, are generally unfavored and typically avoided by many polyphagous lepidopteran species, including the gypsy moth Lymantria dispar (L.) (Lepidoptera: Lymantriidae). We tested the deterrent effects of eight alkaloids using two-choice feeding bioassays. Each alkaloid was applied at biologically relevant concentrations to glass fiber disks and leaf disks from red oak trees (Quercus rubra) (L.), a plant species highly favored by these larvae. All eight alkaloids tested on glass fiber disks were deterrent to varying degrees. When these alkaloids were applied to leaf disks, only seven were still deterrent. Of these seven, five were less deterrent on leaf disks compared with glass fiber disks, indicating that their potency was dramatically reduced when they were applied to leaf disks. The reduction in deterrency may be attributed to the phagostimulatory effect of red oak leaves in suppressing the negative deterrent effect of these alkaloids, suggesting that individual alkaloids may confer context-dependent deterrent effects in plants in which they occur. This study provides novel insights into the feeding behavioral responses of insect larvae, such as L. dispar, to selected deterrent alkaloids when applied to natural vs artificial substrates and has the potential to suggest deterrent alkaloids as possible candidates for agricultural use.     

The impact of invasive grasses on the population growth of Anemone patens, a long-lived native forb

Negative impacts of invasive plants on natives have been well documented, but much less is known about whether invasive plants can cause population level declines. We used demographic models to investigate the effects of two invasive grasses on the demography and population growth of Anemone patens, a long-lived native perennial of North American grasslands. Demographic data of A. patens growing in patches characterized by Bromus inermis, Poa pratensis, or native grasses were used to parameterize integral projection models. Models based on both average conditions and those allowing for environmental stochasticity indicate that A. patens is slowly increasing in patches of native grass (lambda = 1.02) and declining in patches of invasive grasses, particularly those dominated by B. inermis (lambda = 0.93). Extinction probabilities indicate that A. patens should persist in native grass patches, but has a much higher probability of extinction in Bromus patches compared to Poa patches. While sensitivity analyses showed that survival had the biggest effect on population growth rates in all habitats, results of a Life Table Response Experiment (LTRE) revealed that slower individual growth rates in patches of invasive grasses contributed the most to the observed reduction in population growth. These results suggest that invasive grasses may cause slow declines in A. patens, despite short-term coexistence, and that controlling B. inermis only would not be sufficient to ensure A. patens persistence.     

Evaluating spectroscopic and chromatographic techniques to resolve dissolved organic matter via end member mixing analysis

Real-time or near real-time in-situ monitoring of dissolved organic matter (DOM) composition in natural waters and engineered treatment systems provides critical information to water quality scientists and engineers, particularly when the monitoring techniques can provide some information about the chemical nature of DOM. The efficacy of various indices derived from rapid, low-cost spectroscopic and chromatographic techniques to discriminate DOM composition was tested for samples prepared from well-defined mixtures of purified Aldrich humic acid (PAHA) and Suwannee River fulvic acid (SRFA). Sensitivities of the discrimination indices were examined by comparing (1) the differences between measured values and those predicted based from mass balance and the end member characteristics, and (2) the linear correlations between index values and mass ratios of the DOM mixtures. Size exclusion chromatography (SEC) results revealed that the weight-average molecular weight (MW(w)) may be a useful approach for tracking DOM mixing processes, although the number-average molecular weight (MW(n)) may be better for distinguishing different DOM compositions. Specific ultraviolet absorbance measured at 254 nm (SUVA(254)) performed better as a discrimination index than did two previously recommended absorbance ratios, both in terms of making better predictions of intermediate compositions and in exhibiting a more linear correlation with PAHA mass ratio. Several well-defined peaks in the derivative absorption spectra (301 and 314 nm for the first derivative, 217 nm for the third derivative, and 211 and 224 nm for the fourth derivative) also were found to be promising potential DOM discrimination indices. Finally, a fluorescence ratio based on humic- versus fulvic-like fluorescence proved to be a superior DOM discrimination index for the two DOM end members studied here. In general, this study illustrates the evaluation process that should be followed to develop rapid, low-cost discrimination indices to monitor DOM compositions based on end member mixing analyses.     

Effects of Information on the Social Acceptability of Alternatives to Clearfelling in Australian Wet Eucalypt Forests

The effects of viewing different types of information were investigated in people judging the social acceptability of alternative forest harvest systems. Approximately 500 Tasmanians were shown still-simulated images of four harvest systems (a clearfell system, two aggregated retention systems, and a selective system) and were asked to judge their acceptability. Individual interviews were conducted with 12 of the participants. It was anticipated that people holding different beliefs about the consequences of harvesting would have different responses to information. Cluster analysis was used to group participants according to these beliefs. Responses to still images were compared with responses to two other types of information: information about consequences of the harvest systems in the form of indicator symbols, and information about regeneration over time, presented as visual animations. The effects of information differed across both harvest system and belief cluster groups of participants. The largest effects of information occurred in people who held a mix of beliefs about consequences. Within this group, participants who viewed the indicators rated a 30% aggregated retention system higher and selective harvesting lower, than those who did not view the indicators. Viewing animated sequences led to slightly higher ratings of the more intensive harvest systems and significantly lower ratings of the selective harvest system than those based on the still images. The interview data provided examples of interviewees viewing information critically against their own values and beliefs. Only some interviewees appeared to use it in judging social acceptability     

Solid-Phase Microextraction As A Tool for Studying Volatile Compounds in Frog Skin

Solid-phase microextraction (SPME) is an effective technique for studying frog volatile secretions. Its primary advantage is in its application to sampling live animals. the ability to sample an organism over an extended period allows changes in an individual's chemical signature to be determined. the presence of eucalyptol in the skin secretion of Ewing's tree frog, Litoria ewingi, was used to assess the effectiveness of SPME in sampling frog volatiles. Rapid sample times coupled with the polydimethylsiloxane/divinylbenzene (PDMS/DVB) fibre provided the best signal/noise ratio for the majority of frog volatiles analysed, and importantly resulted in the least amount of stress to the animals involved.     

Diffusion of US army chemical weapons disposal technologies: public perception of technology attributes

This study was conducted to identify factors that influence individuals' acceptance of environmental management technologies for cleaning up hazardous materials. The study sample consisted of approximately 2600 residents living within emergency response zones surrounding eight US Army's Chemical Weapons Stockpile sites. The findings suggest that residents perceive clear differences between the desirable characteristics of the two technologies: incineration and neutralization. In a relative comparison, the majority of positive technological attributes were associated with incineration. Positive perceptions toward incineration were associated with individuals who trust the Army, who perceive that the media have made them more trusting of weapons disposal activities, who are ready to participate, and who are male. Unlike incineration, there was insufficient evidence that individual factors influence variations in perceptions toward neutralization. No community factor was related to perceptions toward either incineration or neutralization.