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911.
IAN G. JAMIESON 《Conservation biology》2011,25(1):115-123
Abstract: The number of individuals translocated and released as part of a reintroduction is often small, as is the final established population, because the reintroduction site is typically small. Small founder and small resulting populations can result in population bottlenecks, which are associated with increased rates of inbreeding and loss of genetic diversity, both of which can affect the long‐term viability of reintroduced populations. I used information derived from pedigrees of four monogamous bird species reintroduced onto two different islands (220 and 259 ha) in New Zealand to compare the pattern of inbreeding and loss of genetic diversity among the reintroduced populations. Although reintroduced populations founded with few individuals had higher levels of inbreeding, as predicted, other factors, including biased sex ratio and skewed breeding success, contributed to high levels of inbreeding and loss of genetic diversity. Of the 10–58 individuals released, 4–25 genetic founders contributed at least one living descendent and yielded approximately 3–11 founder–genome equivalents (number of genetic founders assuming an equal contribution of offspring and no random loss of alleles across generations) after seven breeding seasons. This range is much lower than the 20 founder–genome equivalents recommended for captive‐bred populations. Although the level of inbreeding in one reintroduced population initially reached three times that of a closely related species, the long‐term estimated rate of inbreeding of this one population was approximately one‐third that of the other species due to differences in carrying capacities of the respective reintroduction sites. The increasing number of reintroductions to suitable areas that are smaller than those I examined here suggests that it might be useful to develop long‐term strategies and guidelines for reintroduction programs, which would minimize inbreeding and maintain genetic diversity. 相似文献
912.
Yang Wang Wenjie Du Lianliang Chen Haoran Wang Ziyang Shan Zhengyang Zhou Wenwei Li 《环境科学学报(英文版)》2023,35(2):745-757
Air pollution is a major obstacle to future sustainability, and traffic pollution has become a large drag on the sustainable developments of future metropolises. Here, combined with the large volume of real-time monitoring data, we propose a deep learning model, iDeepAir, to predict surface-level PM2.5 concentration in Shanghai megacity and link with MEIC emission inventory creatively to decipher urban traffic impacts on air quality. Our model exhibits high-fidelity in reproducing pollutant concentrations and reduces the MAE from 25.355 µg/m3 to 12.283 µg/m3 compared with other models. And identifies the ranking of major factors, local meteorological conditions have become a nonnegligible factor. Layer-wise relevance propagation (LRP) is used here to enhance the interpretability of the model and we visualize and analyze the reasons for the different correlation between traffic density and PM2.5 concentration in various regions of Shanghai. Meanwhile, As the strict and effective industrial emission reduction measurements implementing in China, the contribution of urban traffic to PM2.5 formation calculated by combining MEIC emission inventory and LRP is gradually increasing from 18.03% in 2011 to 24.37% in 2017 in Shanghai, and the impact of traffic emissions would be ever-prominent in 2030 according to our prediction. We also infer that the promotion of vehicular electrification would achieve further alleviation of PM2.5 about 8.45% by 2030 gradually. These insights are of great significance to provide the decision-making basis for accurate and high-efficient traffic management and urban pollution control, and eventually benefit people's lives and high-quality sustainable developments of cities. 相似文献
913.
Heidi C. Pearson 《Behavioral ecology and sociobiology》2009,63(10):1437-1446
In societies characterized by a high degree of fission-fusion dynamics, individuals adjust their grouping patterns according
to the shifting balance of costs and benefits associated with grouping. This study examines influences on fission-fusion dynamics
for dusky dolphins (Lagenorhynchus obscurus) in Admiralty Bay, New Zealand. This area is an important foraging habitat for dusky dolphins during the winter and spring.
Admiralty Bay has little predation risk, but nearshore mussel farms may infringe on available habitat. I used generalized
estimating equations to determine the influences of coordinated foraging, predation risk, and presence of mussel farms on
party size, rate of fission-fusion, and behavioral state. I conducted 168 boat-based group focal follows totaling 168 h. The
proportion of individuals observed foraging was positively related to party size and rate of party fusion. Resting had no
effect on party size and did not vary according to location. Near mussel farms, traveling decreased, and rate of party fission
decreased. I conclude that (1) coordinated foraging strategies are a primary influence on fission-fusion dynamics within this
population, (2) dolphins may respond to decreased predation risk by not adjusting party size or location during resting, and
(3) areas near mussel farms are not used for traveling. 相似文献
914.
915.
KEVIN M. BROWN R. MICHAEL ERWIN MILO E. RICHMOND P. A. BUCKLEY JOHN T. TANACREDI DAVE AVRIN 《Environmental management》2001,28(2):207-224
During the 1980s, the exponential growth of laughing gull (Larus atricilla) colonies, from 15 to about 7600 nests in 1990, in the Jamaica Bay Wildlife Refuge and a correlated increase in the bird-strike
rate at nearby John F. Kennedy International Airport (New York City) led to a controversy between wildlife and airport managers
over the elimination of the colonies. In this paper, we review data to evaluate if: (1) the colonies have increased the level
of risk to the flying public; (2) on-colony population control would reduce the presence of gulls, and subsequently bird strikes,
at the airport; and (3) all on-airport management alternatives have been adequately implemented. Since 1979, most (2987, 87%)
of the 3444 bird strikes (number of aircraft struck) were actually bird carcasses found near runways (cause of death unknown
but assumed to be bird strikes by definition). Of the 457 pilot-reported strikes (mean = 23 ± 6 aircraft/yr, N= 20 years), 78 (17%) involved laughing gulls. Since a gull-shooting program was initiated on airport property in 1991, over
50,000 adult laughing gulls have been killed and the number of reported bird strikes involving laughing gulls has declined
from 6.9 ± 2.9 (1983–1990) to 2.6 ± 1.3 (1991–1998) aircraft/yr; nongull reported bird strikes, however, have more than doubled
(6.4 ± 2.6, 1983–1990; 14.9 ± 5.1, 1991–1998). We found no evidence to indicate that on-colony management would yield a reduction
of bird strikes at Kennedy Airport. Dietary and mark–recapture studies suggest that 60%–90% of the laughing gulls collected
on-airport were either failed breeders and/or nonbreeding birds. We argue that the Jamaica Bay laughing gull colonies, the
only ones in New York State, should not be managed at least until all on-airport management alternatives have been properly
implemented and demonstrated to be ineffective at reducing bird strikes, including habitat alterations and increasing the
capability of the bird control unit to eliminate bird flocks on-airport using nonlethal bird dispersal techniques. Because
the gull-shooting program may be resulting in a nonsustainable regional population of laughing gulls (>30% decline), we also
recommend that attempts be made to initiate an experimental colony elsewhere on Long Island to determine if colony relocation
is a feasible management option. 相似文献
916.
917.
钱资荡是金坛市目前直接饮用水源地,根据环境监测结果,它已处于中营养化后期。借鉴国内外先进的湖泊管理经验,运用系统工程的思想和方法提出了切实可行的金坛市饮用水源地保护方案。该方案由4个工程子系统组成,(1)截污工程:在岸丘桥和南州桥位置各筑一节制闸(而岸丘桥工程又是首选工程),以封住湖泊两头入流,杜绝污染物进入水源地的截污工程;(2)引水工程:是截污工程的配套工程,利用一游长荡 湖来补充水量,并对3个引水工程设想进行了系统分析,推荐涵管方案,同时将长荡湖作为该市战略水源地一并纳入保护体系中;(3)湿地生态处理工程:对进入荡区前的芦苇区进行综合整治,发展以芦苇为主的湿地生态处理工程;(4)环湖绿色自然保护带工程:包括建设围湖芦苇荡、环湖林带、绿色食品基地以及污泥处置。最后还提出了三级水域保护区范围、水域行政管理体系建设以及工程方案分步实施计划。 相似文献
918.
Farmer models of socio-ecologic systems: Application of causal mapping across multiple locations 总被引:1,自引:0,他引:1
John Fairweather 《Ecological modelling》2010,221(3):555-562
Modelling ecological or environmental problems has potential to provide understanding of the causes of such problems and to indicate how to better manage them. Özesmi and Özesmi (2004) showed that cognitive or causal mapping can be used to develop maps of socio-ecological systems but these maps were based on stakeholders concerned with one ecosystem. This article shows how maps from a number of different dairy farmers in different locations, but each considering his or her own farm, can be used in meta analysis to make maps that represent how farmers think their farm ecosystem works. It also shows that the combination of causal mapping with the additional technique of Q method provides a useful solution to the practical problem of selecting from a sufficiently broad range of factors with potential to use in a map. Causal mapping in single or multiple locations contributes to the goal of using peoples’ knowledge of ecosystems to improve our understanding of socio-ecological systems. 相似文献
919.
Abstract It is the major purpose of the paper to present the urban land-banking planning and its functions of promoting the urban land-banking system and land use administration. The urban land-banking system has the potential attribute of acting as an irreplaceable role in urban land administration, but its unexpected function-deviation has impacted its implementation effect in China. A few city governments are attempting to deal with the problem by the urban land-banking planning which is expected to contribute to the extension of urban function, optimization of urban patterns, promotion of urban core competitiveness and overall construction of the urban value chain. In this paper, we primarily discuss the necessity, functions, purposes and main contents of the urban land-banking planning. Subsequently, the implementing situation of the urban land-banking system in Nanjing is analyzed, including its integrated mode, spatio-temporal quantitative distribution and main characteristics. Finally, the background and targets including total, compositions, space, and regulation points are gradually introduced to present the Nanjing land-banking planning version 2. 相似文献
920.
《Environmental Communication: A Journal of Nature and Culture》2013,7(3):302-319
Modern technological disasters and their human and environmental consequences often defy the imagination in their immensity and complexity. As such, their rhetorical constructions often lack tangibility and a sense of material reality for those not directly involved. These amorphous constructions are consolidated into a view of technological disaster and threats of disaster in which the rhetorical dimensions are analogous to those of ghosts portrayed in popular literature and film—a view the author terms the “technospecter.” Drawing on the public discourse surrounding a tragic pipeline explosion near Carlsbad, New Mexico, this study identifies the rhetorical dimensions of the technospecter and discusses how the construction of the specter reinforces the meta-narratives that constrain pro-environmental action. 相似文献