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111.
This paper synthesizes information on the spatial and temporal dynamics of wood in small streams in the Pacific Northwest region of North America. The literature on this topic is somewhat confused due to a lack of an accepted definition of what constitutes “small” streams and what is the relative size of woody debris contained within the channel. This paper presents a matrix that defines woody debris relative to channel size and then discusses the components of a wood budget. Headwater streams are in close proximity to wood sources and, in steeplands, are often tightly constrained by steep hillslopes. Special consideration is given to ecosystem characteristics and to management practices that affect the wood dynamics in this context. Knowledge gaps and uncertainties that can be used to guide future research are identified. Very little is currently known about the role of mass wasting in wood recruitment and storage relative to other processes, such as bank erosion and mortality, in larger streams. Further, very little work has addressed the relative importance of different wood depletion processes, especially those associated with wood transport. The effect of other ecosystem variables on wood dynamics locally across a watershed (from valley bottom to mountaintop) and regionally across the landscape (from maritime to continental climates) is not addressed. Finally, the scientific community has only begun to deal with the effects of management practices on wood quantity, structure, and movement in small streams.  相似文献   
112.
Environment, Development and Sustainability - The study utilized the tree covers per cent, agroforestry suitability, present and future (2050) climate, agriculture vulnerability (2050), percentage...  相似文献   
113.
A total of two hundred and forty random samples were collected equally from mutton, liver and kidney of 40 local (Jordanian) and 40 imported Australian sheep (40 each sub sample). Fresh samples were collected from 12–18 m old sheep slaughtered in abattoirs in Jordan in 2002. Besides, 40 fresh mutton samples of imported Chinese sheep were collected from different markets. Atomic absorption spectrometry (AAS) was used to estimate the lead (Pb) content of the samples. Results indicated that Australian mutton had significantly higher (p < 0.05) mean of lead pollution than that of the local and Chinese muttons. The mean concentration of lead (mg/kg) in Australian, local and Chinese muttons was 4.30, 3.15 and 2.17, respectively. The mean concentration of lead in Australian sheep liver was significantly higher (p < 0.05) than that recorded in the local sheep liver. The mean concentration of Pb in Australian and local sheep liver was 5.69 and 4.52 mg/kg, respectively. The mean concentrations of Pb in the kidney of the Australian and local sheep were not significantly different (p > 0.05). They were 4.59 and 3.87 mg/kg, respectively.On the basis of the samples lead level, 85, 92 and 87.5% of local, Australian and Chinese mutton respectively, exceeded the international safe permissible limit of 1.0 mg/kg. Furthermore, the effect of Pb on animal and human health was discussed.  相似文献   
114.
Environmental Science and Pollution Research - Abandoning shredded waste tyre rubber (WTR) in cement-based mixes facilitates safe waste tyre disposal and conserves the natural resources used in...  相似文献   
115.
Environmental Science and Pollution Research - Microplastics (MP) pollution is an emerging threat to life and the environment. These particles are not restricted to human-inhabited lands but also...  相似文献   
116.
Environmental Science and Pollution Research - Economic growth in modern-day world get attention primarily through innovation and higher productivity, which places technology and knowledge at the...  相似文献   
117.
Environmental Science and Pollution Research - Cadmium is an important widely distributed heavy metal in the environment due to its several industrial uses, while milk thistle is an important herb...  相似文献   
118.
Environmental Science and Pollution Research - This research paper presents the results of an experimental investigation of the degradation of three different contaminants including progesterone...  相似文献   
119.
This study investigates for the first time the feasibility of isolating nanocellulose from several selected feedstocks via a novel Ni(II)-hydrolysis process, including lignocellulosic biomasses (oil palm trunk, banana peel and coconut husk) and processed biomasses (newspaper, tissue paper and cotton linter), with an obtained gravimetric yield ranging from 59.6 to 86.2%. The isolation of nanocellulose products from these selected feedstocks was verified by the successive removal of most of their non-cellulosic components (lignin and hemicellulose) and cellulose amorphous regions, the increase in the crystallinity index and the nanoscale of the individual crystals. Most importantly, the resultant nanocellulose products rendered better thermal stability than that of corresponding original sources, which are highly potential to be utilized as the new renewable sources of reinforcement materials with potential applications in bio-nanocomposites and thermoplastics. Therefore, this work proves the viability of direct production of nanocellulose from a variety of cellulosic sources by using Ni(II)-based transition metal salt catalyst. The results suggested that the concept of waste to wealth could be well executed from the obtained nanocellulose, which are greatly potential for various industrial applications.  相似文献   
120.
Environmental Science and Pollution Research - This study was designed to assess the gradual increase in the use of insecticides on vegetables and to familiarize the consumers regarding the...  相似文献   
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