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991.
FLORES, the Forest Land Oriented Resource Envisioning System, is a framework to facilitate quantitative modelling of ecological,
economic and social issues at the landscape scale. This issue ofSmall-scale Forest Economics, Management and Policy describes the evolution of FLORES from a concept to a series of models calibrated for diverse locations, and documents the
lessons learned.
The idea to construct and use landscape-scale models of the forest frontier, based on simulating household decisions and land
use at a spatial scale close to the field level, arose from a desire to add rigour to land-use policy research at CIFOR, the
Center for International Forestry Research (Vanclay 1995). This simulation modelling approach to addressing interdisciplinary
issues, where people are strongly interacting with forest resources, became known as FLORES, the Forest Land Oriented Resource
Envisioning System (Vanclay 1998). Muetzelfeldtet al. (1998) constructed a simple prototype of a FLORES model to illustrate the concept and demonstrate the ability of a system-dynamics
modelling environment to animate such a model (Muetzelfeldt and Taylor 1997, 2001, Muetzelfeldt and Massheder 2003). In 1999,
FLORES became a reality, when 50 scientists from diverse disciplines met in Bukittinggi, Indonesia to construct the first
FLORES model styled on this prototype (CIFOR 1999, Vanclayet al. 2003).
The research reported in this special issue was made possible by generous financial support from the Department for International
Development (UK), the European Community, the Asian Development Bank (under RETA 5812) and the Center for International Forestry
Research. The views expressed herein are those of the authors alone. We would like to thank the following people who have
assisted in the production of this special issue by acting as anonymous referees for these and other papers: Andy Warner,
Brendan Moran, Bruno Verbist, Chris Dake, Chris Legg, Doug Sheil, Euan Mason, Francois Bousquet, Frank Vanclay, Geoff Slaughter,
James Gambiza, John Herbohn, John Poulsen, Jungho Suh, Mike Spilsbury, Paul Phillips, Paul van Gardingen, Phil Norman, Philip
Nyhus, Roger Wheate, Ross Sigley, Steve Harrison and Tom Evans. Thanks also to the editorial staff, especially Steve Harrison,
John Herbohn and Jungho Suh, for making this special issue possible. 相似文献
992.
Conjugation of δ-endotoxin from Bacillus thuringiensis with abamectin, a toxin of Streptomyces avermitilis, was carried out to form a new type of biocide, GCSC-BtA based on “Germany-China Scientific Cooperation” research, for the control of agricultural insect pests. The strategy for biochemical linkage was designed by conjugating an amino group in B.t. protoxin with a carboxyl group in carboxylated abamectin under the treatment of conjugator EDC [1-Ethyl-3-(3-dimethylaminopropyl carbodiimide Hydrochloride)]. The formation of B.t. protoxin was processed by solubilizing B.t. crystal in 25?mM dithiothreitol (DTT) at 37?°C for 2?h. The carboxylated abamectin was formed by carboxylating the NaH-activated abamectin with 10?mg/ml butyric anhydride at 111?°C in a water-circumfluent condensation device for 2?h. The conjugating reaction, consisting of 5?mg/ml B.t. protoxin, 10?mg/ml carboxylated abamectin and 19.17?mg/ml EDC, was successfully conducted at room temperature for 24?h. Significant differences were found between pure abamectin, carboxylated abamectin and the conjugated BtA by means of UV-photo absorptions recorded at wavelengths 354, 438, 518, 600?nm (P?<?0.01). LT50 of the conjugated GCSC-BtA to the 3rd instar larvae of Plutella xylostella (L.) (Lep., Plutellidae) was 35.27 μg a.i./ml, about 62?% and 76?% of that caused by the B.t. protoxin and the caxboxylated abamectin, respectively. The conjugated GCSC-BtA caused 87.14?% mortalities in larvae of P. xylostella, 93.75?% in adult Myzus persicae (Sulzer) (Hom., Aphididae) and 89.33?% in adult Phyllotreta vittata Fabricius (Col., Chrysomelidae) as compared to 48.33?% by the B.t. crystal only in P. xylostella. The symptoms caused by conjugated GCSC-BtA in the 3rd instar of P. xylostella were black color in the head part and white-yellow in the abdomen of dead larvae, which differed from the black color or the white-yellow all along the body caused by either the B.t. crystal or the abamectin, respectively. It was concluded that the conjugated GCSC-BtA biocide had a broader host spectrum and a faster killing speed than either the B.t. crystal or abamectin alone for the control of agricultural pests. 相似文献
993.
A survey of forestry practices and attitudes was undertaken in four communities in Leyte, the Philippines, to improve understanding
of the social and economic factors affecting small-scale forestry development. The survey had three main data collection activities
— initial focus group discussions (FGDs), household interviews, and reporting and validation FGDs. A team of enumerators was
selected for household interviews which consisted of both males and females, to avoid potential problems of unwillingness
of people to talk with those of the opposite gender. The interviewers were also required to be able to speak local dialects
(Cebuano and Waray Waray), the survey questionnaires being administered in these dialects. Various methods were used to gain
the support and assistance of local government units and barangay captains. Some difficulty was experienced by the survey
team in the first community due to barangay elections at the time of the survey, and the requirement by the University of
Queensland Ethics Committee that respondents sign a consent form. This requirement was found to be not culturally appropriate
for the Leyte smallholder communities. Offering goods at the end of the interview was found to be of limited value for encouraging
participation in the survey. Provision of food and drinks were found to encourage FGD participants to express their views,
but too much alcohol had a negative effect. The importance of providing comprehensive feedback to respondents and involving
them and other stakeholders in development of policy recommendations was apparent. These survey experiences provide valuable
insights which are not generally available in textbooks on sample surveys, and provide lessons for planning and conducting
smallholder community survey into natural resource management issues. 相似文献
994.
Forest commons are regarded as a means to support local development and sustainable forest conditions. To evaluate the development
impact of Swedish forest commons, comparative surveys have been undertaken in three regions, and the differences in forest
condition and management between categories of commons as well as their relation to other forest ownerships have been assessed.
Regional differences between the by-laws, historical development and geographical conditions are apparent. It is concluded
that two of three regions have an overly restrictive harvesting policy given the purpose of the forest commons and the official
forest policy. The study results underline the importance of evaluation of the performance of forest management in relation
to management objectives, to ownership alternatives and to the impact of local variations in preconditions. 相似文献
995.
LIZhao-hua MikioKOBAYASHI 《林业研究》2004,15(3):233-242
In the past, utilization of bamboo resources in China has been traditionally dominated by direct consumption of local farmers as minor forest products with weak linkage with market. In recent years, the over-supply of grains and rapid degradation of agricultural environment call for alternative crops that can be developed through integrating the environmental plantation with the market demands. Closely associated with forestry and agriculture, bamboo is able to deal with the new challenges which China‘s agriculture is facing. Of 534 documented bamboo species in China, 153 species produce edibleshoots and of which 56 species are recommended for agricultural plantation; 139 species provide timbers and of which 58 species recommended; 116 species can be splited as good strips for weaving and of which 22 species recommended; 88 species are considered as garden bamboos and of which 34 species recommended; 45 species are able to produce paper pulp and of which 18 species recommended. 相似文献
996.
A new isoflavonol triglycoside, biochanin A 7-O-beta-D-apiofuranosyl-(1-->5)-beta-D-apiofuranosyl-(1-->6 )-beta-D- glucopyranoside (1), was isolated from Andira inermis roots in addition to the known compounds genistein 7-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside and lanceolarin. 相似文献
997.
We evaluated differences between the forest floors and the establishment and growth of coniferous seedlings in fenced (13 years)
and unfenced plots on Mt Ohdaigahara where the sika deer (Cervus nippon) population density is high. Large coniferous seedlings (height > 0.05 m) were less abundant in the unfenced plot, as a result
of deer browsing. Small coniferous seedlings (height < 0.05 m), however, were more abundant in the unfenced plot, where most
seedlings of Abies homolepis were found on bare ground and those of Picea jezoensis var. hondoensis were found on buttresses and fallen logs. The large area of bare ground in the unfenced plot was caused by deer browsing.
Deer therefore have an indirect effect on the emergence and growth of small coniferous seedlings by modifying the forest floor. 相似文献
998.
In order to develop a fireproof wooden material, the synergic effect of fire-retardant chemicals and wood coatings was studied.
The fire performance was evaluated by cone calorimeter. Impregnation of fire retardants including polyphosphatic carbamate,
and ceramic coatings including alkoxy metal salt improved the fire performance of wooden materials. This treatment made it
possible to meet the guidelines for fire performance of noncombustible materials in Japan. In addition to the vacuum-pressure
impregnation treatment, hot-and-cold-bath impregnation treatment is an effective way to develop fire-retardant wood by impregnating
fire retardant and ceramic coating. The weatherability of the developed material was also investigated. The ceramic coating
was resistant to light and moisture.
Part of this report was presented at 54th Annual Meeting (Sapporo, August 2004) and the 55th Annual Meeting (Kyoto, March
2005) of the Japan Wood Research Society 相似文献
999.
This study is part of an effort to improve the quality of dried shiitake mushrooms (Lentinula edodes) in accordance with consumer preference. Results are presented of a trend survey that examined the preferences of consumers
using questionnaires combined with sensory evaluation. From the original preference (OP) survey, the distributions of OP divided
by age class (AC) were statistically equal to the results obtained in 2000. The medians of OP for teenagers and twenties were
“neutral” and “slightly like,” respectively. A firm preference change occurred between teenagers and those in their twenties.
It is empirically realized that sensory intensity (SI) scores that were too high or too low led to a low hedonic preference
(HP) score. The same tendency was seen for “neutralists” and “likers.” In addition, almost all distributions concerned with
HP had no significant difference between 2000 and 2005; for example, that of SI divided by AC. These results showed that the
preference for dried shiitake mushroom has been unaffected by the passage of the past 5 years. Dried shiitake mushrooms have
been used from ancient times and for many dishes; therefore, the overall preference appears to have remained unchanged. 相似文献
1000.
世界贸易组织(简称WTO),作为处理世界自由贸易机制的国际组织,允许为可持续发展和保护自由贸易和环境选择利用世界自然资源。中国作为世界贸易组织成员国,签定入世议定书,入世后中国在林业的可持续发展方面受到世界贸易组织的条约和原则的制约和挑战。中国的林业资源应当作为基础资源加以保护,政府的行政管理职能在世界贸易组织的原则下加以改革。因此,中国林业的可持续发展的目.标是优先处理环境保护和经济发展的关系。在入世条件下,按照世界惯例,中国林业资源可持续发展问题瞄准中国林业体制改革,以便适用中国天然林业战略,依靠科技进步依法保护中国环境,特别是在中国林业保护和处理环境和自然资源等关系方面。依据世界贸易组织的协议和规则,建立林业的生态化体系,尤其是GATT20条的规定,保护中国林业可持续发展,为中国林业创建国际环境。表1参21。 相似文献