Lemurs and the Regeneration of Dry Deciduous Forest in Madagascar

Abstract: We sought to assess the role of lemurs for seed dispersal in the dry deciduous forest of western Madagascar and the possible consequences of the demise of lemurs for forest regeneration. Forest regeneration was studied in eight plots in two large blocks of primary forest and in seven fragments of primary forest (1 plot per fragment). In 4 of the 15 study plots, the abundance of saplings was negatively and significantly correlated ( p < 0.05) with the abundance of mature individuals of the same tree species. In another 10 study plots there were negative correlations, although these were not significant on the community level. Second-order statistics were significant with p < 0.001 and indicated that seed dispersal away from the parent trees was important for successful establishment of saplings. Apart from possibly the bush pig ( Potamochoerus larvatus ), only one vertebrate species of the dry forest, the brown lemur ( Eulemur fulvus ), ingested seeds> 11 mm long and passed them through its digestive tract unharmed. These results for lemurs were based on direct observations and fecal analyses. To evaluate the role of E. fulvus , we compared regeneration in forest plots with and without E. fulvus . In forest fragments without E. fulvus , fewer lemur-dispersed tree species regenerated than would be expected based on the presence of mature tree species that are lemur-dispersed ( p < 0.05). No such effect was seen in primary forests with E. fulvus or for trees whose seeds can also be dispersed by other vertebrates. Thus, regeneration of the dry deciduous forest of western Madagascar with the complete set of primary forest tree species seems to depend upon the presence of E. fulvus .     

Efficiency of energy delivery systems: III. Assessing potential energy savings of a comprehensive insulation program

It is possible to develop large quantities of energy by installing a comprehensive regional insulation program. This paper develops a computer model for examining the quantity of energy that may be saved in a region if such a program is undertaken. The program requires data on: number of houses, type of houses and present degree of insulation. The results indicate that in the region under consideration it is possible to make available more energy, far cheaper, through insulation than by the alternative of constructing a large power plant.     

Metals in tern eggs in a New Jersey estuary: A decade of change

We compared levels of eight heavy metals in common tern eggs collected in 1982 (n=24) from coastal New Jersey with archived specimens collected from the same colonies in 1971 (N=9). Levels of all metals, except cobalt, showed a significant decrease over the 11 year period, with lead and nickel showing the greatest decline. Mercury levels declined over 50% based on geometric means. Cadmium and mercury showed the lowest levels in both years. Pair-wise correlation coefficients on log-transformed data revealed lower correlations in 1971, whereas most metal pairs showed significant correlations in 1982. Mercury levels showed significant positive correlations with cobalt, cadmium, and nickel in 1971, but were not correlated with levels of any other metal in 1982.     

Cadmium and lead in common terns (Aves: Sterna hirundo): Relationship between levels in parents and eggs

We analyzed cadmium and lead levels in feathers of mated pairs of common terns (Sterna hirundo) and in their eggs to determine if metal levels in eggs correlated with female levels, and whether there were intrapair and intermetal correlations. Eggs had significantly lower lead levels (89 ng g^-1) and cadmium levels (4.0 ng g^-1) than adult feathers (500 and 50 ng g^-1 respectively). Adult females had higher metal levels than males. Cadmium and lead levels were correlated across families for females, males and eggs. Lead, but not cadmium, levels were correlated in females and their eggs.     

Mercury bioaccumulation in organisms from three Puerto Rican estuaries

We analyzed mercury levels in shrimp (Palaemonetes sp.), Blue Crabs (Callinectes sp.), fish (Tarpon Megalops atlantica and Tilapia Tilapia mossambica), lizards (Ameiva exsul), Cattle Egret (Bubulcus ibis) and Moorhen (Gallinula chloropus) in three estuaries in Puerto Rico in 1988. There were no quantifiable concentrations greater than the method detection limit of mercury in shrimp, crabs and lizards from any site. Mercury levels were also below detection limits in Tilapia, except for specimens collected at Frontera Creek, allegedly contaminated with mercury. However, mercury levels ranged from 92–238 g/kg (wet weight) in Tarpon, a predaceous fish that feeds on smaller fish. Few of the birds had detectable levels of mercury. Our results indicate relatively low concentrations of mercury in biota collected in all of the three estuaries at most trophic levels, although 10 of 12 Tarpon fillet samples from Frontera had detectable mercury compared to 3 of 12 fillet samples for the other two lagoons.This project was partially funded by an EPA consent decree (Dynamac, Inc.) and NIEHS grant (ESO 5022) to EOSHI.     

Distribution and speciation of metals in annual rings of black willow

Information on the spatial distribution and speciation of metals in nonhyperaccumulator plants is lacking. This study used synchrotron X-ray fluorescence (SXRF) compositional imaging to investigate the spatial distribution of Ni, Mn, Cu, Zn, and Fe in annual rings of black willow (Salix nigra L.) collected from a metal-contaminated area, and used X-ray absorption spectroscopy (XAS) to investigate Ni and Mn speciation in regions of the annual rings with elevated Ni concentrations. Annual rings were recollected in early 2003 from an individual known to be enriched with Ni from previous studies. Compositional imaging showed Ni and associated co-contaminants conservatively located in an annual ring. When compared with a corresponding photomicrograph, SXRF compositional images showed that metals were sharply constrained by the boundaries of the annual ring, indicating a sudden onset and cessation of uptake, and a lack of post-growth mobility of the metals. There was a particularly strong correlation between Ni and Mn in the metal-enriched annual ring (r = 0.8822), which suggested similar transport and binding behavior of these elements. X-ray absorption spectroscopy showed Ni and Mn to be present in the 2+ oxidation state. X-ray absorption near edge structure spectroscopy (XANES) fingerprinting of localized, highly Ni-enriched regions within the lumen of willow xylem vessels found similarities with Ni-pectic acid complexes, Ni-histidine, and NiSO4.     

An ecologically oriented database to guide remediation and reuse of contaminated sites

This article presents a database developed to determine the potential reuse of contaminated sites for primarily ecologically and culturally based activities. The database consists of 172 quantitative and qualitative measures of on‐site land suitability, ecological, cultural, and recreational value, and off‐site suitability, economic, and demographic information. Using sites owned by the U.S. Department of Energy (DOE) as a case study, the article evaluates the quality of available data and suggests ways of using it for planning ecologically sensitive remediation activities and future land use. This type of database can be developed and used by anyone who needs to select, review, or evaluate site remediation and future land use options. Also discussed are the challenges associated with compiling and using data that has been generated by many sources over several years. © 2003 Wiley Periodicals, Inc.     

Choosing remediation and waste management options at hazardous and radioactive waste sites

This article discusses a process for finding insights that will allow federal agencies and environmental professionals to more effectively manage contaminated sites. The process is built around what Etzioni (1968) called mixed‐scanning, that is, perpetually doing both comprehensive and detailed analyses and periodically re‐scanning for new circumstances that change the decision‐making environment. The article offers a checklist of 127 items, which is one part of the multiple‐stage scanning process. The checklist includes questions about technology; public, worker, and ecological health; economic cost and benefits; social impacts; and legal issues. While developed for a DOE high‐level radioactive waste application, the decision‐making framework and specific questions can be used for other large‐scale remediation and management projects. © 2002 Wiley Periodicals, Inc.     

Incorporating ecology and ecological risk into long‐term stewardship on contaminated sites

The long‐term management of environmental contamination will be a major activity at many sites in the foreseeable future. While human health issues often drive decisions about cleanup, restoration, and long‐term stewardship, ecological considerations are also major driving forces and are of paramount importance to the public. Incorporation of ecological considerations into decisions about environmental protection, both short term and long term, requires (1) understanding public perceptions of ecological values, including aesthetics and existence values, (2) understanding contamination issues within a context of the structure and functioning of ecosystems, (3) developing bioindicators of ecological health (including human), (4) developing indicators of ecosystem functioning, and (5) developing and implementing a biomonitoring plan before, during, and after remediation so that adverse effects can be ascertained before they become irreversible. Both remediation/restoration and long‐term stewardship goals must be informed by public policy mandates that include public participation and healthy human and ecological systems. This article examines these issues as they relate to cost‐effective, long‐term protection of human and ecological health on contaminated lands. © 2002 Wiley Periodicals, Inc.