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Forest roads often increase runoff and sediment loss, thus greatly impacting hydrological processes in mountainous watersheds. While there has been previous investigation on best management practices (BMPs) to reduce soil erosion from forest roads, few studies have attempted to optimize BMPs based on how much they can decrease sediment connectivity between forest roads and streams. To close this gap in knowledge, we analyzed the spatial relationship between forest roads and streams, presented the spatial distribution of sediment connectivity by integrating the forest roads into the calculation of the index of connectivity (IC), determined how sediment connectivity would respond to additional BMPs through simulating scenarios, and used these data to optimize the BMPs so they would intercept the greatest sediment loads. We found that forest roads and streams in the Xiangchagou watershed in the Dabie Mountain area of China tend to occur within 180 m of each other; however, within the same buffer zones, streams are more often accompanied by forest roads. IC was greatest near road–stream crossings but smaller near streams and forest roads, and it tended to decrease as the buffer distance increased. Furthermore, we found that sediment connectivity was decreased through running a variety of scenarios that used sediment basin and riparian buffers as BMPs between forest roads and streams. Specifically, within this watershed, riparian buffers should be 64 m wide, and there should be 30 sediment basins with a minimum upslope drainage area of 2 ha. At these quantities, the BMPs in this watershed would significantly affect sediment connectivity. By contrast, beyond these thresholds, increasing the width of riparian buffers or the number of sediment basins does not lead to meaningful sediment reductions. In this way, we were able to use the mean change point method to determine the optimal sediment basin quantity (30 with corresponding minimum upslope drainage area of 2 ha) and the optimal riparian buffer width (64 m) for the Xiangchagou watershed. While these results are a first approximation in a novel research area, they can guide forest managers and stakeholders to design and optimize BMPs that control the delivery of eroded sediments associated with forest roads. [ABSTRACT FROM AUTHOR]

Ecosystem management in the face of uncertain disturbances has triggered increasing practices of resilience thinking. A multiscale probabilistic simulation-optimization framework is developed based on the nested nature of watersheds to inform decision robustness for Best Management Practices (BMPs). We presented a novel approach using hybrid Bayesian Networks (BNs) as interpretable and probabilistic emulators of process-based models. The hybrid BNs established at the scale of Hydrologic Response Units (HRUs) are embedded into simulation-optimization, whereby we analyze the cost-effectiveness-robustness of candidate BMP strategies at the subbasin scale. The optimal strategy is identified in compliance with water quality standards using watershed-scale integer programming. We apply the approaches in a typical intensively cultivated plateau watershed adjacent to Lake Dianchi, one of the three most eutrophic lakes in China. Our findings suggest that the hybrid BNs, incorporating both quantitative and qualitative information, are reliable emulators of the Soil and Water Assessment Tool (SWAT) in capturing critical pathways of diffuse phosphorus. Tradeoffs among cost, effectiveness, and robustness follow the law of diminishing marginal benefits. The optimum BMP strategies vary with policymakers' preference toward robustness levels. Our findings indicate that robustness should be accounted for as an additional decision attribute besides costs and pollution mitigation. The benefits of the modeling framework are to (i) reduce over 99% computation complexity and support efficient decision-making under multifaceted uncertainties; (ii) improve interpretability and reliability of machine learning emulators; and (iii) inform policymakers of robustness with the probability of water quality restoration success. [Display omitted] • A novel multiscale probabilistic simulation-optimization framework is presented. • The success probability of mitigation efforts is informed as decision robustness. • We use hybrid BNs as emulators of process-based models to improve interpretability. • The model effectively reduces computational budget whilst preserving model accuracy. [ABSTRACT FROM AUTHOR]

Best management practices (BMPs) have been widely used in managing agricultural nonpoint source pollution (ANSP) at the watershed level. Most BMPs are related to land use, tillage management, and fertilizer levels. In total, seven BMP scenarios (Reforest1, Reforest2, No Tillage, Contour tillage, and fertilizer level 1-4) that are related to these three factors were estimated in this study. The objectives were to investigate the effectiveness and cost-benefit of these BMPs on ANSP reduction in a large tributary of the Three Gorges Reservoir (TGR) in China, which are based on the simulation results of the Soil and Water Assessment Tool (SWAT) model. The results indicated that reforestation was the most economically efficient of all BMPs, and its net benefits were up to CNY 4.36×10 years (about USD 7.08×10 years). Regarding tillage practices, no tillage practice was more environmentally friendly than other tillage practices, and contour tillage was more economically efficient. Reducing the local fertilizer level to 0.8-fold less than that of 2010 can yield a satisfactory environmental and economic efficiency. Reforestation and fertilizer management were more effective in reducing total phosphorus (TP), whereas tillage management was more effective in reducing total nitrogen (TN). When CNY 10,000 (about USD 162) was applied to reforestation, no tillage, contour tillage, and an 0.8-fold reduction in the fertilizer level, then annual TN load can be reduced by 0.08, 0.16, 0.11, and 0.04 t and annual TP load can be reduced by 0.04, 0.02, 0.01 and 0.03 t, respectively. The cost-benefit (CB) ratios of the BMPs were as follows: reforestation (207 %) > contour tillage (129 %) > no tillage (114 %) > fertilizer management (96 and 89 %). The most economical and effective BMPs can be designated as follows: BMP1 (returning arable land with slopes greater than 25° to forests and those lands with slopes of 15-25° to orchards), BMP2 (implementing no tillage on arable land with slopes less than 15°), and BMP5 (0.8-fold less than that of 2010). [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to evaluate the effect of different mechanical forces on the expansion of the palatine suture using transsutural distraction osteogenesis. Methods: A total of 48 dogs were used in this study. The experimental groups were treated with a custom-designed internal distractor. Bone regeneration was determined with x-rays and histology. The computed values underwent statistical analyses using analysis of variance. Results: The maxillary complex was most noticeably advanced with an applied mechanical force of 600 g (20.15 ± 1.36 mm), compared with forces of 400 g (19.88 ± 1.41 mm) and 800 g (2.24 ± 0.93 mm). Immunohistochemical staining showed that the expression of bone morphogenetic protein-2 and bone morphogenetic protein-4 fluctuated with different mechanical forces. These changes were statistically significant when 600 g of force was applied within 30 days of distraction (P < .05). Conclusions: Transsutural distraction osteogenesis in the growing dog should be safe and well tolerated in inducing bony lengthening of the maxilla, and the optimal force is 600 × g. Bone morphogenetic protein-2 and bone morphogenetic protein-4 may play an important roles in the signaling pathways that link mechanical forces and biological responses. [ABSTRACT FROM AUTHOR]

As a signaling molecule, bone morphogenetic protein 8B (BMP8B) plays an essential role in bone metabolism and is able to regulate thermogenesis and energy balance, which suggests that BMP8B gene may be a new candidate for growth traits. Here, to characterize the effects of BMP8B gene on growth traits, we first used three Chinese indigenous cattle breeds (n=845) to detect single nucleotide polymorphisms (SNPs). Five novel SNPs of BMP8B gene (g.-242C>T, g.2164C>T, g.2639T>C, g.2900C>G and g.10817C>T) were identified by DNA pool sequencing and forced PCR-RFLP. And then we associated the five SNPs with four growth traits (body weight, body length, heart girth, and hucklebone width). Results from association analysis showed that the SNPs 1, 2, and 3 affected growth trait(s) markedly (P<0.05). Further, 6 combined haplotypes were constructed to guarantee the reliability of analysis results. There were also significant differences in body length, heart girth and body weight between the 6 combined haplotypes (P<0.05), but not in hucklebone width (P>0.05). Collectively, our results suggest a modulatory role of BMP8B gene in cattle growth and development, and 3 SNPs could be used as molecular markers in early marker assisted selection (MAS) in beef cattle breeding program., (© 2013 Elsevier B.V. All rights reserved.)