In this study, the information needs of non-industrial private forest owners in Finland, after logging operations, were investigated. The study was carried out as an online survey in 2017. The survey was targeted at non-industrial private forest owners who had sold their timber during the previous 10 years (2008–2017) and whose email addresses were in the customer relationship management system of a large wood procurement company in Finland. A response link for the survey was successfully sent to 31,988 forest owners, of whom 3323 replied (response rate: 10.4%). The final study data included 3284 non-industrial private forest owners. The results of the study, which need to be interpreted cautiously due to the low response rate, showed that the forest owners want better-quality reporting after logging operations. Furthermore, the results suggested that gender, age, education, occupational status, place of living, size of, and access to, forest property, and length of, and objectives for, forest ownership have a significant effect on their information needs. Younger, highly-educated, female, urban-living and multi-objective forest owners with larger forest holdings and short forest ownership tenures desired more information. Particularly, the respondents conveyed that they would like more and better information about thinning harvesting result. The results also indicated that when different groups of forest owners call for certain information, there is a need for producing different types of reports after logging operations for different forest owner segments.
Coniferous trees growing in the boreal and temperate zones have a clear annual cycle of photosynthetic activity. A recent study demonstrated that the seasonal variation in photosynthetic capacity of Scots pine (Pinus sylvestris L.) could be attributed mainly to the light response curve of photosynthesis. The magnitude of the light response curve varied over the season while its shape remained constant, indicating that the two physiological parameters quantifying the curve-the quantum yield per unit internal carbon dioxide concentration and the corresponding light-saturated rate-remained proportional to each other. We now show, through modeling studies, that the quantum yield (and hence the light-saturated rate) is related to the annual cycle of temperature through a delayed dynamic response. The proposed model was tested by comparing model results with intensive measurements of photosynthesis and driving variables made from April to October in three shoots of Scots pine growing near the northern timberline. Photosynthetic capacity showed considerable acclimation during the growing season. A single model describing photosynthetic capacity as a reversible, first-order delay process driven by temperature explained most of the variation in photosynthetic capacity during the year. The proposed model is simpler but no less accurate than previous models of the annual cycle of photosynthetic capacity. 相似文献
Processes to develop criteria and indicators (C and I) for sustainableforest management are often expert driven. Although the long-termobjective of the Nepalese forest policy is sustainable forestmanagement, no national level C and I specifically for thishave been developed. However, the Ministry of Forests and SoilConservation awards an annual prize to successful communityforest user groups (CFUGs) based on evaluation according to10 criteria. This study explored local C and I for successfulforest management in Nepal through six meetings with CFUG members.A total of 14 local criteria and 52 indicators for awardinga prize to successful CFUGs were identified, and comparisonwith official C and I was undertaken. Most conspicuously, localC and I focus more on environmental and governance-related aspectsthan the official list, and the official list leaves much tothe discretion of the evaluator. The study concludes that developmentof a national level C and I for sustainable forest managementcould benefit from involvement of local forest users. 相似文献
Sea buckthorn (Hippopha? rhamnoides L.) is a rich source of flavonols, especially isorhamnetin. Most prospective cohort studies have indicated some degree of inverse association between flavonoid intake and coronary heart disease. Animal and human studies suggest that sea buckthorn flavonoids may scavenge free radicals, lower blood viscosity, and enhance cardiac function. The effects of flavonol aglycones derived from sea buckthorn on the risk factors of cardiovascular disease as well as their absorption were studied in humans. The flavonols, ingested with oatmeal porridge, did not have a significant effect on the levels of oxidized low-density lipoprotein, C-reactive protein, and homocysteine, on the plasma antioxidant potential, or on the paraoxonase activity. Flavonols at two dosages in oatmeal porridge were rapidly absorbed, and a relatively small amount of sea buckthorn oil added to the porridge seemed to have increased the bioavailability of sea buckthorn flavonols consumed at the higher dose. 相似文献
If the mean (integral) of a convex or concave function is estimated by evaluating the response function at the mean of the environmental variable, the estimate is necessarily biased. This study computes from empirical radiation data the errors obtained when mean photosynthesis is estimated using mean radiation. Furthermore, three different methods of estimating mean photosynthesis are compared in a case where the second power of the irradiance is also integrated and the variance is thus known. The smallest errors are obtained when the irradiance distribution is approximated by a two-point distribution: the bias is reduced to one-tenth and the root mean square error to one-third compared to the situation when only mean radiation is used. The results indicate that, if accurate estimates are needed for integrals of nonlinear responses, the second power of radiation or any other fluctuating environmental variable should also be measured. 相似文献
The fatty acid composition and contents of fat and fat-soluble vitamins of three salted products prepared from Icelandic herring were analyzed. The effects of storage on the products over their shelf life, 6 or 12 months, were investigated. The average oil content of salted, gutted herring and salted fillets in vacuum remained constant, 17 and 12% of wet weight, respectively. In the pickled product the oil content decreased during the 12 months of storage from 13 to 12%. The composition of the products was typical for herring, the most abundant fatty acids being oleic (18:1n-9), palmitic (16:0), cetoleic (22:1n-11), and gadoleic (20:1n-9) acids. Monounsaturated acids constituted clearly the main group with a proportion of >50% of all fatty acids. Eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) comprised together >12% of all fatty acids. During storage, some hydrolysis of triacylglycerol (TAG) occurred, causing a slight reduction in practically all esterified fatty acids. In none of the three products was the loss of polyunsaturated fatty acids from TAG greater than the loss of saturated ones, indicating that the loss of EPA and DHA was not due to oxidation. After packing, the average content of vitamins A, D, and E in the products varied between 27 and 87 microg/100 g (wet weight), between 17-28 microg/100 g (wet weight), and between 77-120 microg/100 g (wet weight), respectively. During storage, the level of vitamin A decreased significantly, whereas no loss of vitamin D was observed. The content of vitamin E was low in all products and showed wide variation. When compared to the recommended daily intake, it could be concluded that the products investigated were good and stable sources of long-chain n-3 fatty acids (EPA, DHA) and vitamin D. 相似文献