Conservation impacts of commercial cultivation of endangered and overharvested plants

Overharvesting is one of the greatest threats to species survival. Farming overharvested species is a conservation strategy that can meet growing market demand and conserve wild populations of the target species. This strategy is compatible with the international community's desire to uphold the right of local communities to use biological resources to support their livelihoods. However, studies investigating whether farming can alleviate poaching pressure have focused almost exclusively on animals. To address the shortfall in plant-focused studies, we compiled information on commercial cultivation of threatened plants to assess its conservation benefits. Because China's rising middle class has rapidly intensified demand for wildlife products, we searched the scientific literature published in Chinese (China National Knowledge Infrastructure and Baidu) and in English. We found 32 reports that contained data on 193 internationally or nationally threatened plant species that were under commercial cultivation. These reports showed that cultivations of 82% of the 193 species were sustained by collecting whole plants from the wild periodically or continuously. Although based on a small sample size, species that were maintained in cultivation only through artificial propagation or seeds collected in the wild were likely associated with a reported reduction in wild harvesting of whole plants. Even so, results of correlation analyses suggested that production system, scale, and when a species began being cultivated had little effect on conservation status of the species, either globally or in China. However, species brought into cultivation relatively recently and on a smaller scale were more likely to have undergone a reduction in collecting pressure. Farming of nonmedicinal plants was most problematic for species conservation because wild plants were laundered (i.e., sold as cultivated plants). For effective conservation, policy to guide cultivation operations based on the target species’ biological characteristics, cultural significance, market demand, and conservation status is needed.     

Sonographic features of ileal duplication cyst at 12 weeks

Enteric duplication cyst is a congenital abnormality that is believed to arise from abnormal recanalization of the bowel during embryogenesis. Previous reports suggest that the condition may be suspected prenatally by sonographic demonstration of an intra-abdominal cystic mass in the second and third trimesters. We present the sonographic features of a fetus with ileal duplication cyst at 12 weeks of gestation, which show that the condition may present in the first trimester of pregnancy. Copyright © 2002 John Wiley & Sons, Ltd.     

Generation rates and emission factors of particulate matter and particle-bound polycyclic aromatic hydrocarbons of incense sticks

The generation rates and emission factors of particulate matter and associated polycyclic aromatic hydrocarbons (PAHs) from incense burning were assessed in a laboratory setting. The differences among different segments of the same stick, among different sticks of the same kind of incense, and between two kinds of manually made Chih-Chen incense sticks (A and B) were evaluated. Joss sticks were burned inside a 44 cm long elutriator; personal environmental monitors fitted into the top of the elutriator were used to take PM2.5 and PM10 samples of incense smoke. Samples were analyzed for PAHs by gas chromatography-flame ionization Detector. It was found that particle and associated PAHs were generated approximately at 561 microg/min (geometric standard deviation (GSD) = 1.1) and 0.56 microg/min (GSD = 1.1) from Incense A, and at 661 microg/min (GSD = 1.7) and 0.46 microg/min (GSD = 1.3) from Incense B, respectively. One gram of Incense A emitted about 19.8 mg (GSD = 1.1) particulate matter and 17.1 microg (GSD = 1.2) particulate-phase PAHs, while one gram of Incense B produced around 43.6 mg (GSD = 1.1) of particles and 25.2 microg (GSD = 1.2) of particle-bound PAHs. There were significant differences in emissions between Incenses A and B, although they belong to the same class of incense. A 10-20% variability in emissions was observed in the main part of the manually produced stick, and a larger variation was found at both tips of the combustible part.     

Comparisons of the dust/smoke particulate that settled inside the surrounding buildings and outside on the streets of southern New York City after the collapse of the World Trade Center, September 11, 2001

The collapse of the World Trade Center (WTC) on September 11, 2001, generated large amounts of dust and smoke that settled in the surrounding indoor and outdoor environments in southern Manhattan. Sixteen dust samples were collected from undisturbed locations inside two uncleaned buildings that were adjacent to Ground Zero. These samples were analyzed for morphology, metals, and organic compounds, and the results were compared with the previously reported outdoor WTC dust/smoke results. We also analyzed seven additional dust samples provided by residents in the local neighborhoods. The morphologic analyses showed that the indoor WTC dust/smoke samples were similar to the outdoor WTC dust/smoke samples in composition and characteristics but with more than 50% mass in the <53-microm size fraction. This was in contrast to the outdoor samples that contained >50% of mass above >53 microm. Elemental analyses also showed the similarities, but at lower concentrations. Organic compounds present in the outdoor samples were also detected in the indoor samples. Conversely, the resident-provided convenience dust samples were different from either the WTC indoor or outdoor samples in composition and pH, indicating that they were not WTC-affected locations. In summary, the indoor dust/smoke was similar in concentration to the outdoor dust/smoke but had a greater percentage of mass <53 microm in diameter.     

重力作用下尘粒运动的数值解法

提出了重力作用下尘粒运动的数值解法。依据尘粒的重力、浮力及所受到的阻力推出了尘粒自然沉降时的运动方程。当尘粒的运动在斯托克斯领域内时采用理论公式求解其运动轨迹,当尘粒的运动进入非斯托克斯领域内时,提出了修正斯托克斯公式的方法以达到用理论公式来近似模拟该领域内的尘粒自然沉降运动     

The efficiency of the multi-walled carbon nanotubes used for antibiotics removal from wastewaters generated by animal farms

Environmental Science and Pollution Research - In the recent years, residual antibiotics are considered to be emerging environmental pollutants due to their continuous input and persistence into...     

Evaluating the air quality impacts of the 2008 Beijing Olympic Games: On-road emission factors and black carbon profiles

The aggressive traffic interventions and emission control measures implemented to improve air quality during the 2008 Beijing Olympic Games created a valuable case study to evaluate the effectiveness of these measures on mitigating air pollution and protecting public health. In this paper, we report the results from our field campaign in summer 2008 on the on-road emission factors of carbon monoxide, black carbon (BC) and ultrafine particles (UFP) as well as the ambient BC concentrations. The fleet average emission factors for light-duty gasoline vehicles (LDGV) showed considerable reduction in the Olympic year (2008) compared to the pre-Olympic year (2007). Our measurement of Black Carbon (BC), a primary pollutant, at different elevations at the ambient site suggests consistent decrease in BC concentrations as the height increased near the ground level, which indicates that the nearby ground level sources, probably dominated by traffic, contributed to a large portion of BC concentrations in the lower atmospheric layer in Beijing during summertime. These observations indicate that people living in near ground levels experience higher exposures than those living in higher floors in Beijing. The BC diurnal patterns on days when traffic control were in place during the Olympic Games were compared to those on non-traffic-control days in both 2007 and in 2008. These patterns strongly suggest that diesel trucks are a major source of summertime BC in Beijing. The median BC concentration on Olympic days was 3.7 μg m⁻³, which was dramatically lower than the value on non-traffic-control days, indicating the effectiveness of traffic control regulations in BC reduction in Beijing.     

Nomogram for Relating Particle and Particle Cloud Parameters

Three concentration units, i.e., mass density, number density, and surface area, often are alternatively used to describe an aerosol cloud. While most aerosol clouds are composed of poly-disperse particles, the nomogram based upon monodisperse spherical particles (Figure 1) has been found useful for relating these different concentration values.     

Carbonyl emissions from commercial cooking sources in Hong Kong

Cooking fumes are an important carbonyl emission source, especially in a highly urbanized city, such as Hong Kong. Cooking exhaust from 15 commercial kitchens of a variety of cooking styles was sampled and analyzed for a suite of 13 carbonyl compounds. Carbonyl compositions were varied among the different cooking styles. Formaldehyde was generally the most abundant carbonyl, and its contribution to the total carbonyl amount on a molar basis ranged from 12 to 60%. Acrolein was also found to be an abundant carbonyl in the cooking exhaust. The highest contribution by acrolein to the total carbonyls was found to be 30% in the exhaust of a western-style steak restaurant. Long-chain saturated carbonyls, that is, heptanal, octanal, and nonanal, accounted for a significant fraction (> 40%) of the total carbonyls in kitchens that always used heated cooking oils. Two dicarbonyls, glyoxal and methylglyoxal, had a various presence in the cooking emissions, ranging from negligible to 10%. The presence of benzaldehyde and tolualdehyde was mostly negligible in the sampled kitchen exhaust. Annual emission rates of both individual carbonyls and total carbonyls were estimated for various types of commercial kitchens. Local-style fast-food shops contributed the highest total carbonyl emissions per year mainly because of the large number of this kind of restaurant in Hong Kong. The citywide annual emission rates of the three most toxic carbonyls, formaldehyde, acetaldehyde, and acrolein, were estimated assuming that the limited number of sampled restaurants were representative of the average restaurants. Such estimates of carbonyl emission rates were comparable to the estimated carbonyl emissions from vehicular sources, suggesting the importance of commercial cooking as a source for carbonyls in Hong Kong.     

气浮/曝气生物滤池/多级过滤/离子交换工艺在印染中水回用中的应用

以宁波某印染企业印染中水回用工程为例,对已建工程进行了具体介绍和分析,探讨了气浮/曝气生物滤池(BAF)/多级过滤/离子交换工艺在印染中水回用中的应用.结果表明,在染色机清污分流的基础上,气浮/BAF/多级过滤/离子交换工艺可以成功应用于印染中水回用,同时具有良好的环境效益和经济效益.