It is better to be ignorant of our moral enhancement: A reply to Zambrano

In a recent issue of Bioethics, I argued that compulsory moral bioenhancement should be administered covertly. Alexander Zambrano has criticized this argument on two fronts. First, contrary to my claim, Zambrano claims that the prevention of ultimate harm by covert moral bioenhancement fails to meet conditions for permissible liberty-restricting public health interventions. Second, contrary to my claim, Zambrano claims that covert moral bioenhancement undermines autonomy to a greater degree than does overt moral bioenhancement. In this paper, I rebut both of these arguments, then finish by noting important avenues of research that Zambrano’s arguments motivate.     

Stand height and cover type complement forest age structure as a biodiversity indicator in boreal and northern temperate forest management

Forest age structure is one of the main indicators of biodiversity in temperate and boreal forests worldwide. This indicator was mainly chosen for the conservation of a subset of rare or sensitive species related to the oldest age classes, not to capture variability across the entire biodiversity spectrum, but is often considered as such. In this study, we analysed alpha and beta diversity in temporary plots of western Quebec, Canada, to consider biodiversity indicators complementary to existing forest age structure targets. Our analysis revealed that considered individually, stand characteristics such as cover type and height are better predictors of changes in site-level contribution to tree beta diversity than age. We also show that plots belonging to different age classes can be similar in terms of tree alpha diversity. Height class was found to have a more significant impact on tree alpha diversity than expected: height was more important than age in coniferous forests, and in deciduous and mixedwood stands it frequently complemented age in explaining the observed diversity patterns. Our results suggest that forest age structure target levels should not be used as the sole indicator of ecosystem sustainability, and that some mature secondary stands can provide significant contributions to biodiversity. We propose that more efficient trade-offs between forest exploitation, ecosystem functioning and environmental conservation can be attained if: (i) forest age structure targets are complemented by cover type and stand height; or (ii) complementary biodiversity indicators of ecosystem sustainability are implemented.     

Risk assessment of heavy metal and metalloid toxicity through a contaminated vegetable (Cucurbita maxima) from wastewater irrigated area: A case study for a site-specific risk assessment in Jhang,Pakistan

The present research was conducted in district Jhang, Pakistan, to evaluate the concentration of metals/metalloids in soil and pumpkin (Cucurbita maxima) irrigated with domestic wastewater. Data revealed that the levels of metals and metalloids in soil samples from two different sites were below the safe limits except Cd, whereas, in the vegetable, the concentrations of As, Se, Ni, Mo, Pb, Mn, and Cu were above the safe limits. The levels of 12 metals and metalloids in the soil were ranged between 0.14 to 22.76 mg/kg at site-I and 0.16 to 22.13 mg/kg at site-II. The levels of these metals in the vegetable were found 0.35 to 61.13 mg/kg at site-I and 0.31 to 53.63 mg/kg at site-II. The transfer factor at both sites was highest for As and Co. The pollution load index recorded for Se, Cu, Cd, Mo, Pb, and Co was greater than 1. The daily intake of As, Mn, and Mo was above the oral reference dose, which reflects that the intake of pumpkin is not safe for the inhabitants of the selected sites. The control measures should be taken to phytoextract heavy metals and metalloids from polluted sites so as to reduce the health risks.     

Stronger dung removal in forests compared with grassland is driven by trait composition and biomass of dung beetles

1. Ecosystem processes depend on the biomass of the involved organisms, but their functional diversity may play an additional role. In particular, the exclusion of key functional groups through habitat disturbance may lead to the breakdown of ecosystem functions. Dung removal is an important process contributing to nutrient cycling and thus productivity in grazed ecosystems. 2. This study investigated the role of different functional groups of dung beetles in dung removal in different habitats within a wood-pasture in two different seasons. An experimental setting with 12 blocks and 108 dung pads was used to investigate short-term dung removal over 1 week of exposure. 3. Dung removal was most strongly affected by habitat type, with almost 40% lower levels in grassland than in adjacent forest and forest gaps. Of all assemblage characteristics, total biomass of tunneller species was the strongest predictor of dung removal, whereas functional diversity showed no significant effect. In accordance with the dung removal pattern at habitat type level, densities of large tunnellers were suppressed in grassland compared with forest. 4. It is concluded that dung removal is habitat-specific and large tunnellers play a disproportionate role in this important ecosystem function in temperate forests.     

A bacteriological survey of an oyster-growing area: The Oualidia Lagoon,Morocco

A 3-year bacteriological survey of an oyster-growing area in Morocco, where the Japanese oyster (Crassostrea gigas) is grown, showed that the contamination of this lagunar ecosystem was not continuous but intermittent and that animal manure and human recreational activities were important sources of pollution. The major source of contamination was of animal origin, except during the summer, when human contamination prevailed.     

主养青鱼池塘生态系统能量转换率的研究

1985—1987年对苏州市郊区主养青鱼池塘生态系统的能量转换率进行了分析。结果表明,主养青鱼净产7.5、11.25、15t/ha 3个产量级型池塘青鲤团头鲂产出能占养鱼总产出能的比例分别为82.49、78.03、79.34％;总投入能(太阳辐射能+辅助能)转移到鱼的总产出能转换率分别为0.19、0.24、0.31％;太阳辐射能转移到毛和净初级生产力的能量转换率分别为0.76、0.90、0.96％和0.61、0.72、0.77％;净初级生产力转移到滤食性鱼净产量的能量转换率分别为4.02、4.63、5.27％;辅助能转移到鱼净产量的能量转换率分别为12.20、11.33。11.74％。在3个产量级型池塘中,以15t/ha产量级的能量转换率为最佳型。     

The nitrogen cycle in lodgepole pine forests,southeastern Wyoming

Storage and flux of nitrogen were studied in several contrasting lodgepole pine (Pinus contorta spp.latifolia) forests in southeastern Wyoming. The mineral soil contained most of the N in these ecosystems (range of 315–860 g · m^–2), with aboveground detritus (37.5–48.8g · m^–2) and living biomass (19.5–24.0 g · m^–2) storing much smaller amounts. About 60–70% of the total N in vegetation was aboveground, and N concentrations in plant tissues were unusually low (foliage = 0.7% N), as were N input via wet precipitation (0.25 g · m^–2 · yr^–1), and biological fixation of atmospheric N (<0.03 g · m^–2 · yr^–1, except locally in some stands at low elevations where symbiotic fixation by the leguminous herbLupinus argenteus probably exceeded 0.1 g · m^–2 · yr^–1).Because of low concentrations in litterfall and limited opportunity for leaching, N accumulated in decaying leaves for 6–7 yr following leaf fall. This process represented an annual flux of about 0.5g · m^–2 to the 01 horizon. Only 20% of this flux was provided by throughfall, with the remaining 0.4g · m^–2 · yr^–1 apparently added from layers below. Low mineralization and small amounts of N uptake from the 02 are likely because of minimal rooting in the forest floor (as defined herein) and negligible mineral N (< 0.05 mg · L^–1) in 02 leachate. A critical transport process was solubilization of organic N, mostly fulvic acids. Most of the organic N from the forest floor was retained within the major tree rooting zone (0–40 cm), and mineralization of soil organic N provided NH₄ for tree uptake. Nitrate was at trace levels in soil solutions, and a long lag in nitrification was always observed under disturbed conditions. Total root nitrogen uptake was calculated to be 1.25 gN · m^–2 · yr^–1 with estimated root turnover of 0.37-gN · m^–2 · yr^–1, and the soil horizons appeared to be nearly in balance with respect to N. The high demand for mineralized N and the precipitation of fulvic acid in the mineral soil resulted in minimal deep leaching in most stands (< 0.02 g · m^–2 · yr^–1). These forests provide an extreme example of nitrogen behavior in dry, infertile forests.     

Dust and ammonia in horse stalls with different ventilation rates and bedding

Airborne particles and ammonia were monitored in horse stalls managed under four conditions. Two ventilation rates, high (27 air changes per h) and low (5 air changes per h) and two bedding types, paper and straw, were employed. At both ventilation rates, the number of airborne particles generated while the stalls were mucked out was higher with straw than with paper. Particles were more efficiently cleared at the higher ventilation rate in both the straw and paper stalls. Ammonia measurements reflected an accumulation over time. In the stalls with low ventilation, ammonia levels were significantly higher than in those stalls with high ventilation regardless of bedding type. Management decisions and their relationships to respiratory disorders are discussed.     

Vesicular-arbuscular mycorrhizal inoculum potential affects the growth of Stryphnodendron microstachyum seedlings in a Costa Rican human tropical lowland

This study used a plant bioassay to investigate the vesicular-arbuscular mycorrhizal (VAM) inoculum potential of soil from three vegetation types (fern, secondary forest, and grass) in an abandoned pasture in the tropical humid lowlands at La Selva, in northeastern Costa Rica. Growth, measured as seedling height, number of leaves, and total (above- and belowground) biomass, of Stryphnodendron microstachyum Poepp. et Endl. (Synon. S. excelsum Harms) seedlings was significantly lower when grown in soil inoculum from the fern areas than in soil inoculum from the forest and grass areas. However, S. microstachyum seedlings grown in the fern inoculum had significantly greater VAM colonization than seedlings grown in the forest and grass inoculum. In addition, roots collected from a dominant plant species from each of the three vegetation types showed that the fern (Nephrolepsis biserrata) had significantly greater mycorrhizal colonization than the tree (Pentaclethra macroloba (Willd.) Kuntze or the grass (Brachiaria spp.). The results of this study suggest that differences in mycorrhizal inoculum potential among vegetation types and its effects on seedling growth may have important implications for the restoration and management of degraded lands.     

Radiological evaluation of bone status in the jaw and in the vertebral column in a group of women

Vertebral bone mineral content was determined in a group of 56 women, ages 30–62. These measurements were compared with the status of supporting bone in the jaws (alveolar, molar and bicuspid) and with gingival health. There was a significant decline in vertebral bone mineral content from the pre- to post-menopausal group. Molar and bicuspid measurements were highly correlated. There was some association between lumbar bone mineral content and molar bone status for postmenopausal women. For postmenopausal women, the cases of greatest percent bone loss in alveolar crest were associated with lower lumbar bone mineral content. Gingival health did not confound the bone status measurements. The 56 subjects did not exhibit the degree of reduction in bone density that is observed in the general population. Further investigation using these radiographic techniques may reveal a link between substantial bone loss in the jaw and moderate to severe bone loss in the lumbar vertebrae.