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991.
Because lack of data impedes the assessment of the conservation of medicinal plants, ethno-medicinal studies are important to fill this gap. This study considered the traditional use of plants for health care by the rural communities in two forested and non-forested regions of Bangladesh. A total of 230 respondents were interviewed accompanied by field observation and voucher specimen collection. Altogether, 68 species of medicinal plants belonging to 38 families distributing over 58 genera were recorded, of which 22 species were common in both regions. Trees were the most commonly utilized growth form and leaves were the most commonly used plant part. Forests and homesteads were the major sources of medicinal plants in forested and non-forested regions, respectively. High use versatility (Relative Importance >1) was represented by 14 species; Emblica officinale L. and Allium sativum L. were the most versatile species. Forty-one individual ailments were treated with the medicinal plants recorded. The ailment categories ‘respiratory problems’ and ‘sexual problems’ received the highest score from the calculation of informants’ consensus factor (F ic) in forested and non-forested regions, respectively. The findings could contribute in the pharmaceutical sector by directing further investigation of bio-active compounds in medicinal plants. Secondly, results could inform the clues for conservation strategies of forest resources in that region.  相似文献   
992.
This paper examines the historical phases of Finnish forest planning from the 1960s to the present day in support of the rational future development of forest planning for family-owned forest holdings. The ‘historical types’ of work—craft work, mass production, process enhancement, and mass customization have been recognized in the Finnish planning discourse to date. Indications of mass customization are typical in the present developmental discussion of forest planning. There are some signals in the current planning debate that are calling for the next activity principle, co-configuration. A forthcoming type of forestry extension activity, labelled adaptive planning, is described in this paper to explicate the demands imposed by a future planning system. The present analysis informs also other contexts outside of Finland, where public and private institutions that support family forest owners face post-industrial challenges.  相似文献   
993.
The potential of veterinary antibiotics (VAs) to impact human and environmental health requires the development and evaluation of land management practices that mitigate VA loss from manure-treated agroecosystems. Vegetative buffer strips (VBS) are postulated to be one management tool that can reduce VA transport to surface water resources. The objectives of this study were to (1) investigate oxytetracycline (OTC) and sulfadimethoxine (SDT) sorption to agroforestry buffer, grass buffer, and cropland soils, (2) evaluate differences in VA sorption to soils collected from different vegetative management and soil series, and (3) elucidate relationships between soil properties and VA sorption. Sorption/extraction isotherms for OTC were well-fitted by the Freundlich isotherm model (r 2 > 0.86). OTC was strongly adsorbed by all soils and the VA was not readily extractable. OTC and SDT solid to solution partition coefficients (K d) values are significantly greater for soils planted to VBS relative to grain crops. Significant differences in OTC and SDT K d values were also noted among the soil series studied. Linear regression analyses indicate that clay content and pH were the most important soil properties controlling OTC and SDT adsorption, respectively. Results from this study suggest that agroforestry and grass buffer strips may effectively mitigate antibiotic loss from agroecosystems, in part, due to enhanced antibiotic sorption properties.  相似文献   
994.
Red flour beetle Tribolium castaneum (Herbst) and rice weevil Sitophilus oryzae (L.) are considered to be the major insect pests in storage. Essential oils from aromatic plants are recognized as proper alternatives to fumigants. Thymus persicus (Ronniger ex Rech. f.) is one of these plants that have medicinal properties and is indigenous to Iran. The essential oil was obtained from aerial parts of the plant and analyzed by GC and GC–MS. Carvacrol (44.69%) and thymol (11.05%) were the major constituents of the oil extracted. In this experiment, fumigant toxicity of the essential oil was studied against T. castaneum, S. oryzae at 27 ± 1°C and 60 ± 5% RH in dark condition. The adult insects were exposed to the concentrations of 51.9, 111.1, 207.4 and 370.4 μl/l air to estimate median lethal time (LT50) values. The fumigant toxicity was increased in response to increased essential oil concentrations. The LT50 values at the lowest and the highest concentrations tested were ranged from 28.09 to 13.47 h for T. castaneum, and 3.86 to 2.30 h for S. oryzae. It was found that S. oryzae adults were much more susceptible to the oil than T. castaneum. After 24 h of exposure, the LC50 values (95% fiducial limit) for T. castaneum and S. oryzae were estimated to be 236.9 (186.27–292.81) and 3.34 (2.62–4.28) μl/l air, respectively. These results suggest that T. persicus essential oil merits further study as potential fumigant for the management of these stored-product insects.  相似文献   
995.
Acorn production patterns and the annual evolution of water relations parameters of Quercus ilex ssp. ballota (Desf.) Samp. in a dehesa (an open woodland forest) subject to various soil treatments (ploughing, ploughing + sowing, control) were studied in southwest Spain from June 2006 to December 2008. The effects of soil water holding capacity and effective soil depth on soil and plant water status and acorn production were also investigated. Water parameters showed significant differences between the ploughing treatment and the control, and there were also significant temporal differences. Xylem water potential ranged from −3.4 ± 0.1 to −0.7 ± 0.2 MPa, and cuticular transpiration was 62.4–192.9 mmol H2O kg−1 s−1. Acorn production did not differ significantly according to soil treatment, and showed large intra-specific variability. Individual values ranged from 0 to 1,220 g m−2 (fresh weight). Positive relationships were found between xylem water potential, cuticular transpiration and relative water content measured at midsummer, and acorn production during the three studied years. These results suggest that climatic conditions and soil water availability have a strong influence on plant water status, and therefore on acorn development during summer. The results also reflect the ability of this species to adapt to the Mediterranean climate by preserving water during dry periods, which to a large extent can be attributed to stomatal closure at high relative water content levels, and low cuticular transpiration during these periods.  相似文献   
996.
The purpose of this research was to study the influence of the vegetation on the soil C pool of forests of pines (Pinus sylvestris) and oaks (Quercus pyrenaica), located in Central-Western Spain. Horizons from selected soils located in these forests were sampled, and the soil organic C (SOC) was determined. In addition, in vitro incubation experiments were carried out, under controlled conditions, to monitor the stability of SOC against the microbial activity. Soil humus fractions were isolated following a classical procedure of chemical fractionation using alkaline solutions, before and after the incubation experiment. A deeper O horizon was found under the pine forest than under oak one; however, higher SOC content was found in the oak site than that under pine one. During the in vitro mineralization process, a lower CO2 production by the soil sample from pine forest was observed, in relation to that emitted by the oak soil. In addition, a lower humification degree was estimated for the soil humus under pines than for that under oaks. In conclusion, replacement of oaks by pines produced a decrease in SOC accumulation and a lower quality of humus in the forest soils.  相似文献   
997.
Post-thinning stump sprout response was assessed in a coast redwood [Sequoia sempervirens (D. Don) Endl.] stand from 5 to 9 years after five treatments were initiated. Nine years after treatment, leaf area index (LAI) ranged from 5.9 to 14.1 and the percent above canopy light (PACL) ranged from 0.8 to 3.9. Sprout responses included rapid self-thinning in all treatments with complete sprout mortality at low light regimes. Self-thinning of clumps increased with greater overstory LAI and poorer light regimes. Leaf area of individual sprout clumps also declined in low light regimes. The probability of sprout survival declined rapidly below 10 PACL and coincided with declining leaf area in sprout clumps. A conceptual model is presented that shows the sensitivity of redwood sprouts to light regime. Results have implications for management of multiaged stands and indicate these redwood coppice systems require relatively severe overstory treatments to provide sufficient light for sprout vigor and growth.  相似文献   
998.
–  • We combined stem volume increment analysis with dendroecological tools to address two unresolved issues concerning oak dieback in Mediterranean areas: early detection of changes in stand growth, and identification of mechanisms for observed growth declines.  相似文献   
999.
–  • The Spanish fir (Abies pinsapo Boiss.) is a conifer endemic to southern Spain and belongs to a Mediterranean basin group of firs considered to be relict. Megagametophyte storage proteins are a useful tool for the evaluation of genetic variability due to the haploid nature of megagametophytes in conifers.  相似文献   
1000.
–  • Studies on wood density variations are necessary for estimating the forest carbon pool. Further, they can help predict the technological properties of wooden end-products. While there have been frequent reports on the relationships between wood density, cambial age, and ring width, there is little information about the historical trend in wood density for the last century, particularly in the context of global climate change.  相似文献   
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