ISSN:1061-2971    

DOI:10.1111/j.1526-100X.1994.tb00036.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractTo evaluate reclamation success on the Wooley Valley phosphate mine in southeastern Idaho, we compared vegetation structure and soil physical, chemical, and elemental properties of several different reclamation treatments with those of a nearby reference area (a nativeArtemisia tridentata vaseyana/Festuca idahoensisassociation) after 14 years. Vegetation data had been collected four years after reclamation, and we were able to compare differences in biomass and species composition between dates on the reclaimed area. Four years after reclamation there were no differences in total biomass between topsoil or spoil or between seed only, seed + mulch, or control treatments on the different soil types. Most treatments were dominated by seeded perennial grasses. Fourteen years after reclamation there were no differences in biomass or cover between spoil and topsoil plots, but on spoil plots the seeded and mulched treatment had higher total biomass and vegetation cover than on control or seed‐only treatments. The seeded perennial legumeMedicago sativawas codominant with the seeded forage grasses on all of the treatments. High initial fertilization rates probably facilitated the early establishment and dominance of the forage grasses; once nutrient levels, especially nitrogen, began to decline, the legume increased in abundance. Similarity between the reclaimed area and the reference or native area was low. Reclaimed treatments had higher biomass but lower species richness. The topsoil and spoil plots had similar soil texture, bulk density, pH, cation exchange capacity, electrical conductivity, and phosphorus. Differences in organic carbon, total nitrogen, carbon: nitrogen ratios, and available moisture were related more to treatments than to soil type. High biomass and, thus, litter input on the seed + mulch treatment on spoil plots resulted in both higher OC and TN than any on other soil/treatment combination. The reclaimed area had lower OC, TN, and available moisture than did the reference area on all but seed + mulch spoil plots. Bulk density was higher on reclaimed plots. The long‐term differences observed between the reclaimed and reference areas parallel those obtained for other western reclamation sites. Although successional trajectories depend on the attribute measured, similarity to native reference areas depends on the initial reclamation methods. We discuss reclamation methods that would increase the structural and functional similarity of reclaimed and reference areas on the Wooley Valley phosphate m

ISSN:1061-2971    

DOI:10.1111/j.1526-100X.1994.tb00037.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractWithin an urban park in southern California, the relationship between the structure and floristics of vegetation and the distribution, abundance, and behavior of wildlife was studied in relatively undisturbed areas (San Luis Rey) and in contiguous areas (Guajome Park) in need of restoration. These data were used to develop recommendations for the enhancement of native animal species in the park. The abundance of amphibians and reptiles was highest in native upland scrub and willow (Salix)‐riparian vegetation types, and lowest in dry, disturbed sites. Western fence lizards (Sceloporus occidentalis) were the most abundant reptile throughout both study areas. Overall, bullfrogs (Rana catesbiana), an exotic species, were the dominant amphibians; the native Pacific treefrog (Hyla regilla) was rare throughout. At both study areas, the small mammal community was dominated by western harvest mice (Reithrodontomys megalotis) and deer mice (Peromyscus maniculatus) and, to a lesser extent, by brush mice (P. boylii) and exotic house mice (Mus musculus). Negative correlations in abundance existed between house mice and harvest mice, and between house mice abundance and overall small mammal abundance. In riparian sites, cottonwood (Populus fremontii) and various height classes of willow were the dominant factors in the majority of bird abundance–habitat‘correlations and where foraging activities were concentrated. Recommendations for enhancing native animal species include reduction of marsh sedimentation, removal of feral species, and development of connections between the park and nearby natural areas. A corridor of native riparian vegetation (primarily cottonwood‐willow) should be developed to replace the existing agricultural fields, thereby linking Guajome with the San Luis Re

ISSN:1061-2971    

DOI:10.1111/j.1526-100X.1994.tb00038.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractRestoration of an abandoned 16‐ha Nike missile base site located on a former wetland in the lower Detroit River (Michigan, U.S.A.) was investigated with an emphasis on wetland restoration. The site included a 2.7‐ha abandoned missile base, a 1.3‐ha lake, 10.4 ha of emergent and submersed wetlands, and 1.8 ha of uplands. Aquatic beds in the shallow bay connected to the river supported floating leaved and submersed aquatics includingNymphaea tiiberosa, Vallisneria antericana, Elodea canadensis, andHeteranthera dubia, with mats of green, filamentous algae. A 10‐ha diked wetland adjacent to the site was dominated byTyphaspp.,Salixspp.,Nymphaea tuberosa, Myriophyllum spicatum, Elodea canadensis, Charasp., andJuncus effusus.Restoration objectives included a nature preserve, an outdoor recreation area, an experimental wetland complex, and an environmental education center. Ten alternative designs were suggested, including four with wetlands open to the bay, three with diked wetlands, and the rest involving island construction, a reconstructed upland site, or a wetland research facility. Alternatives were evaluated for their contribution to local ecology, research, education and wildlife, ease of maintenance, and probability of success. Construction of a wetland resembling conditions before construction of the base was recommended for its low maintenance and opportunity for research on non diked wetland design and construction in protected bays in the Laurentian Great Lakes. Recreational and educational opportunities were also recommended as part of the site rest

ISSN:1061-2971    

DOI:10.1111/j.1526-100X.1994.tb00039.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractEight individual rock iguanas (Iguana pinguis) from Anegada Island were relocated to Guana Island by Lazell, 1984–1987, in order to establish a second population reservoir for this endangered species. The species may have originally occupied the entire Puerto Rico Bank. The relocation has been successful and, in the area currently providing the best habitat, we estimate a density of 9 or 12 animals of various age classes per 19 ha. The optimal area contains a sheep exclosure with relatively dense understory vegetation and numerous exotic as well as native species of plants. Iguana activity is concentrated on east facing slopes and ridge‐tops that get morning sun. Outside the exclosure most edible ground cover and shrubs have been eaten by sheep, leaving toxic or noxious species, such asCrotonorLantana, in the understory whereI. pinguisadults generally forage. Removal of sheep may be critical to continued population growth of these reptiles. Views on relocation or repatriation of other endangered AntilleanIguanaspecies are advanced, with some ideas on minimum viable population sizes and a possible explanation for the extirpation ofI. pinguisfrom much of its former ra

ISSN:1061-2971    

DOI:10.1111/j.1526-100X.1994.tb00040.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractIn land restoration it is imperative to study the potential role of disturbances, biotic or abiotic, that may provide sites for colonization by specific plants. Disturbances can alter community composition by removing species or allowing others to become established. In communities where animal‐generated disturbances open sites for seedling establishment, animals may have important indirect effects on several aspects of plant community structure. Animal disturbances inQuercus havardiicommunities of western Texas appear to open sites for colonization by herbaceous species. These animal disturbances vary in spatial distribution, density, and abiotic and biotic characteristics. The abundance of herbaceous plant seedlings is positively related to bare ground and the number of distinct disturbances. Thus, the density and the spatial distribution of these disturbances may be expected to have an important influence on the abundance and dispersion of plant species. Therefore, successful restoration efforts of sand shinnery oak communities and other similar habitats must consider the effects of animal disturbances and the role of plant‐animal and plant‐soil microbe interactions on plant community composition and the maintenance of plant species dive

ISSN:1061-2971    

DOI:10.1111/j.1526-100X.1994.tb00041.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractThe rates of seston elimination by zooplankton and primary production were measured in Funada‐ike Pond, typical of human‐made impoundments in Japan, from April to September in order to evaluate various treatments of the pond aimed at improving water quality by reducing seston abundance. The treatments included draining the pond water, dredging the bottom mud, eliminating the wastewater inflow, and biomanipulation through removal of all fish. After the treatment, seston abundance was reduced from more than 10 to 0.4–2.5 mg C/liter, and large daphnid species,Daphnia similisandD. magna, occurred and predominated in the zooplankton community. Seston abundance remained at a relatively low level from June to August but increased markedly in late August, while the biomass of zooplankton became high from June to mid‐August and then decreased. A decrease in seston abundance was found when the elimination rate exceeded the primary production rate. The results indicate that the development of daphnid populations was effective in keeping seston abundance at a low level. The relationship between the rate of primary production and the zoo‐plankton biomass required to offset this rate, however, suggests that biomanipulation aimed at increasing zooplankton biomass alone is less effective in a pond with a high primary production. The success in improving water quality in this pond seems to depend not only on the increase in biomass of large daphnid species that resulted mainly from the removal of fish, but also on the decrease in nutrient load that was realized by the other t

ISSN:1061-2971    

DOI:10.1111/j.1526-100X.1994.tb00042.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

Books reviewed in this article:Functions of Nature Evaluation of Nature in Environmental Planning, Management and Decision Making. Rudolf S. de GrootLandscape Restorastion HandbookD. Harker, S. Evans, M. Evans, and K. Harker

ISSN:1061-2971    

DOI:10.1111/j.1526-100X.1994.tb00043.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY