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51.
This paper analyzes how sustained yield (SY) forestry is defined and implemented in Sweden and Russia, two countries with different forest-industrial regimes. We first compare definitions of SY forestry in national legislation and policies. Then we study forest management planning in two large forest management units with respect to: delivered forest products and values, how the harvest level of timber is defined, where the harvest takes place, and what treatments are used to sustain desired forest products and values. In Sweden SY forestry is maximum yield based on high-input forest management, and in Russia it is forestry based on natural regeneration with minimum investments in silviculture. We conclude that how SY forestry contributes to SFM depends on the context. Finally, we discuss the consequences of SY forestry as performed in Sweden and Russia related to its ability to support diverse forest functions, as envisioned in sustainable forest management policy.  相似文献   
52.
Trisomy of the short arm of chromosome 4 is a well-known syndrome, and several observations have been made in the last 30 years. Herein, we report a new observation of trisomy 4p in a fetus with a semi-lobar holoprosencephaly (HPE), dysmorphic features and multiple malformations. The diagnosis of HPE was made, at 33 weeks' gestation, on the fetus of a healthy G1P0 woman. Amniocentesis was performed for chromosome analysis and additional material was found on a chromosome 22. The couple elected to terminate the pregnancy and fetal examination was realized. Conventional and molecular cytogenetic studies were performed on the fetus and the parents, which showed that the additional material found on one chromosome 22 corresponded to the short arm of chromosome 4 and therefore led us to establish a diagnosis of trisomy 4p inherited from the malsegregation of a paternal translocation t(4;22)(q12;q11.1). The etiology of HPE is very heterogeneous; it includes non-genetic factors such as maternal diabetes and genetic causes. HPE cases have been described in association with many chromosomal anomalies, trisomy 13 being the most frequent. However, to our knowledge, HPE has never been previously reported in association with a trisomy involving solely the short arm of chromosome 4. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
53.
3 are damaged annually by snow and wind, roughly corresponding to a value of US$150 million, and in Europe, the damage amounts to hundreds of millions of US dollars each year. To help to reduce these losses, tools for risk assessment within forest management have been developed. Predictions were developed of the risk of damage from snow and wind to Scots pine (Pinus sylvestris L.), Norway spruce [Picea abies (L.) Karst.] and Birch (Betula spp. L.) plots using tree, stand, and site characteristics. The data were obtained from 6756 permanent sample plots within the Swedish National Forest Inventory, which were inventoried twice at five-year intervals between 1983 and 1992. Input data for model development used measurements from the first inventory of tree characteristics for the largest sample tree, stand, and site data, and records of snow and wind damage from the second inventory. Models were developed for three different regions for pine- and spruce-dominated sites, while models for the whole country were developed for birch sites. In general the estimated proportion of damaged plots was highly overestimated (31.7%–56.2%), compared with the observed proportion of 3.4%–11.9%. The models for Norway spruce comprising tree, stand, and site data show the best predictability of damaged plots, with 60.6%–67.6% of plots correctly classified. It is concluded that the models developed can be used to detect sites with a high probability of damage from snow and wind, and thus be used as tools to reduce future damage and costs in practical forestry.  相似文献   
54.
Environmental Chemistry Letters - The anthraquinone dye Remazol Brilliant Blue R is largely used in the textile industry. However, its removal from wastewaters is costly and complex. Many methods...  相似文献   
55.
Regional Environmental Change - The dry forests of Latin America are among the most dynamic deforestation frontiers in the world and are important carbon and biodiversity reservoirs. Our knowledge...  相似文献   
56.
Mitigation and Adaptation Strategies for Global Change - Industrial processes cause significant emissions of greenhouse gases (GHGs) to the atmosphere and, therefore, have high mitigation and...  相似文献   
57.
Viruses from contaminant sources can be transported through porous media to drinking water wells. The objective of this study was to investigate inactivation and sorption of viruses during saturated and unsaturated transport in different soils. Bacteriophages phiX174 and MS-2, and Br- tracer in a phosphate-buffered saline solution were introduced into saturated and unsaturated soil columns as a step function under constant flow rate and hydraulic conditions. Results showed that significantly greater virus removal occurred in the unsaturated columns than in the saturated columns in the two soils containing high metal oxides content. However, the increase in virus retention under unsaturated conditions was not significant in two other soils having high phosphorus and calcium contents and high pH, and in another soil with high organic matter content. The results imply that the extent of water content effect on inactivation and sorption of viruses can range from significant to minimal depending on the properties of the transport medium. We found that the presence of in situ metal oxides was a significant factor responsible for virus sorption and inactivation. Therefore, soils with high metal oxides content may have the potential to be used as hydrological barriers in preventing microbial contamination in the subsurface environments. We also found that the water content effect on virus removal and inactivation strongly depended on solid properties of the testing medium.  相似文献   
58.
Regional Environmental Change - Understanding popular attitudes to climate change can be important in developing effective climate adaptation responses. However, in the Pacific region, which is at...  相似文献   
59.
Strategies are needed to increase the sustainability of phosphorus (P) fertiliser management in agriculture. This paper reports on the potential of pyrolysis treatment to recycle P from renewable materials previously regarded as wastes. The study used K-edge X-ray absorption near-edge structure (XANES) spectroscopy to examine chemical forms of P in the waste feedstock materials and corresponding biochars (pyrolysis at 480–500 °C) of four ligno-cellulosic, plant-based residues and five relatively P-rich livestock and water-treatment by-products, to acquire information on changes in potential P fertiliser value. Pyrolysis enriched P in the biochars by factors of 1.3–4.3, thus offering wide-ranging P fertiliser potential. XANES spectroscopy revealed hydroxyapatite (HAP) as one of the dominant chemical P compounds in the feedstocks, ranging from 14% (rice husks) to 98% (animal bone) of total P. For most materials, pyrolysis increased the proportion of HAP, and pyrophosphates were generated in several cases. These alterations possibly lead to diversity in the P solubility characteristics of the biochars if used as soil amendments; this is an important property of environmentally sound P fertilisers.  相似文献   
60.
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