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[en] The giant panda Ailuropoda melanoleuca is one of the most iconic mammals in the world. The species has experienced declines in its habitat and population due to human disturbance. To protect this species, we investigated the relationship between giant panda habitat use intensity and human disturbance density in the Daxiangling Mountains. The results indicated that, among multiple kinds of disturbances, roads affected the giant panda habitat use significantly. In addition, roads caused the giant panda habitat use intensity to decline sharply. The giant panda nearly stopped using the habitat when road density was more than 0.4 km/km2. Thus, road density should be considered in the protection program. Furthermore, in areas inhabited by giant pandas, we recommend to optimizing and enhancing increased regulations to minimize the expansion and impact of roads. (author)
[en] This paper describes the development and implementation of two ecological restoration projects at the Fernald Preserve that are funded through a CERCLA natural resource damage settlement. The Paddys Run Tributary Project involves creation of vernal pool wetland habitat with adjacent forest restoration. The Triangle Area Project is a mesic tall-grass prairie establishment, similar to other efforts at the Fernald Preserve. The goal of the Fernald Natural Resource Trustees is to establish habitat for Ambystomatid salamander species, as well as grassland birds. Planning and implementation of on-property ecological restoration projects is one component of compensation for natural resource injury. As with the rest of the Fernald Preserve, ecological restoration has helped turn a DOE liability into a community asset. (authors)
[en] Data on the N and C isotopic composition are presented for the Lower Triassic claystones of the Abrek section of southern Primorye (Far East). The results showed five N isotopic intervals and several negative C isotopic excursions of the Induan–lower Olenekian stages of the Abrek section.
[en] A river channel survey was completed along three reaches (totalling 14.3km), i.e. an unregulated stretch and two regulated reaches (with reduced flows) of the Soca River to assess the spatial pattern of CGU type, size, hydraulics and distribution. In addition, one regulated reach was re-surveyed at different discharges to investigate the dynamics of CGUs and their relationship with flow. CGUs were classified and mapped using visual assessment and physical measurements of the hydraulic characteristics (velocity and depth) in each CGU. The effect of flow regulation on the hydraulic character of the river becomes apparent by highlighting differences in the types of CGUs present between the regulated and unregulated reaches. Reduced flows from river regulation also significantly reduces the size of CGUs, alters their hydraulic character, and affects the longitudinal distribution of types by creating greater habitat fragmentation. Hydraulic preferences for spawning habitat of marble trout (Salmo marmoratus) were obtained from previous research. The hydraulic character of CGUs were analysed at different discharges and combined with the hydraulic preferences of the species to evaluate the impact of flow regulation on habitat availability. Analysis shows that intermediate measured flow provides increased spawning habitat availability in the chosen reach for this target species.
[en] Systems that allow users to store and retrieve spatial data, provide for analyses of spatial data, and offer highly detailed display of spatial data are referred to as geographic information systems, or more typically, GIS. Since their initial usage in the 1960s, GISs have evolved as a means of assembling and analyzing diverse data pertaining to specific geographical areas, with spatial locations of the data serving as the organizational basis for the information systems. The structure of GISs is built around spatial identifiers and the methods used to encode data for storage and manipulation. This paper examines how GIS has been used in typical environmental assessment, its use for cumulative impact assessment, and explores litigation that occurred in the United States Federal court system where GIS was used in some aspect of cumulative effects. The paper also summarizes fifteen case studies that range from area wide transportation planning to wildlife and habitat impacts, and draws together a few lessons learned from this review of literature and litigation.
[en] Bioinspired design approaches seek to exploit nature in order to construct optimal solutions for engineering problems as uniform temperature control in multizone systems. The ideal free distribution (IFD) is a concept from behavioural ecology, which describes the arrangement of individuals in different habitats such that at equilibrium, all habitats are equally suitable. Here, we relax the IFD's main assumptions using the standing-crop idea to introduce dynamics into the supplies of each habitat. Then, we make an analogy with a multizone thermal system to propose a controller based on the replicator dynamics model, in order to obtain a maximum uniform temperature subject to constant power injection. Besides, we analytically show that the equilibrium point of the controlled system is asymptotically stable. Finally, some practical results obtained with a testbed and comparisons with the theoretical results are presented.
[en] The Albeni Falls Interagency Work Group was actively involved in implementing wildlife mitigation activities in 2000. The Work Group met each quarter to discuss management and budget issues affecting Albeni Falls wildlife mitigation. Members of the Work Group protected a total of 1,242 acres of wetland habitat in 2000. The total amount of wildlife habitat protected for Albeni Falls mitigation is approximately 4,190 acres (4,630 Habitat Units). Approximately 16% of the total wildlife habitat lost has been mitigated. Land management activities were limited in 2000 as protection opportunities took up most staff time. Administrative activities increased in 2000 as funding was more evenly distributed among Work Group members. As a result, implementation is expected to continue to increase in the coming year. Land management and monitoring and evaluation activities will increase in 2001 as site-specific management plans are completed and implemented
[en] In this paper, we discussed some major issues that hinder giant panda protection, such as diverse and mixed threats, habitat fragmentation, as well as the survey method to be improved, and some new protection actions appeared, such as the pilot program for the giant panda national park system and the administration of the giant panda national park was established. These information could provide important information for giant panda protection.
[en] Insects are the most diverse organisms on earth consisting of more than 900 thousand species. However, only few of them are considered agricultural pests. Life history traits such as high fecundity, fast population growth, and high dispersal ability have been used to characterize agricultural pest insects. However, many other non-pest insects also share these traits, which indicates that there has not been a decisive condition characterizing agricultural pest insects. Agricultural habitats are risky and ephemeral to pests because of pest control and harvesting. The usual arithmetic mean fitness cannot be used to measure the persistence of these pests, because the maximal mean fitness is achieved only when they exhibit no dispersal, but that leads to immediate extinction. Using a geometric mean fitness model, we propose a quantitative measure of long-term reproductive success for agricultural pest insects. By using this approach, we can evaluate the trade-off between long-distance dispersal and high reproduction correctly and estimate the condition for the long-term persistence of pest insects in agricultural habitats. We discuss some general perspectives of pest control from the proposed characterization.