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As human influences fragment native communities and ecosystems, remaining land must be better managed to conserve many elements
of biodiversity. Much of this land is privately held, yet traditional private land-use management practices often further
diminish biodiversity by promoting favored or edge-adapted species.
Today, private land stewards are increasingly aware of and concerned about biodiversity, but little guidance exists for them
to make land-use decisions incorporating principles and knowledge from conservation biology. Consequently, most management
strategies are highly subjective. This article addresses that problem by introducing current conservation wisdom to management
and use of private lands. The result is a model program for developing land management plans, with the goal of maintaining
viable populations and natural distributions of native species and communities from a landscape perspective.
The program establishes a protocol for classifying sites according to the importance of their species, communities, and other
elements to global and regional biodiversity. These site classifications are based on the management objectives necessary
to maintain important elements. Once managers classify a site, the program provides management standards, general stewardship
principles, examples of land management strategies, and basic monitoring and evaluation procedures. 相似文献
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Reed F. Noss 《Conservation biology》2003,17(5):1270-1275
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Correlation between Fitness and Genetic Diversity 总被引:39,自引:0,他引:39
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Yulong Wang Zhonghao Bai Libo Cao Matthew P. Reed Kurt Fischer Angelo Adler 《Traffic injury prevention》2015,16(4):S75-S83
Objective: Recent field data analyses have shown that the safety advantages of rear seats relative to the front seats have decreased in newer vehicles. Separately, the risks of certain injuries have been found to be higher for obese occupants. The objective of this study is to investigate the effects of advanced belt features on the protection of rear-seat occupants with a range of body mass index (BMI) in frontal crashes.Methods: Whole-body finite element human models with 4 BMI levels (25, 30, 35, and 40 kg/m2) developed previously were used in this study. A total of 52 frontal crash simulations were conducted, including 4 simulations with a standard rear-seat, 3-point belt and 48 simulations with advanced belt features. The parameters varied in the simulations included BMI, load limit, anchor pretensioner, and lap belt routing relative to the pelvis. The injury measurements analyzed in this study included head and hip excursions, normalized chest deflection, and torso angle (defined as the angle between the hip–shoulder line and the vertical direction). Analyses of covariance were used to test the significance (P <.05) of the results.Results: Higher BMI was associated with greater head and hip excursions and larger normalized chest deflection. Higher belt routing increased the hip excursion and torso angle, which indicates a higher submarining risk, whereas the anchor pretensioner reduced hip excursion and torso angle. Lower load limits decreased the normalized chest deflection but increased the head excursion. Normalized chest deflection had a positive correlation with maximum torso angle. Occupants with higher BMI have to use higher load limits to reach head excursions similar to those in lower BMI occupants.Discussion and Conclusion: The simulation results suggest that optimizing load limiter and adding pretensioner(s) can reduce injury risks associated with obesity, but conflicting effects on head and chest injuries were observed. This study demonstrated the feasibility and importance of using human models to investigate protection for occupants with various BMI levels. A seat belt system capable of adapting to occupant size and body shape will improve protection for obese occupants in rear seats. 相似文献
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