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961.
刘璨 Maxim Lobovikov Daniel Murdiyarso Hiroyasu Oka Yeo-Chang Youn Keith Barney Makoto Inoue Hariadi Kartodihardjo Pia Katila Tetsuya Saito Bintang Simangunsong Yasuhiro Yokota 吕金芝 林海燕 《绿色中国(A版)》2005,52(22):33-36
在过去的20年里,亚洲林业经历了引人注目的转型,包括从计划经济到市场经济的转变,从天然林供给木材到人工林供给木材的转变,木材替代品与非木质林产品的增加,地方分权与当地群众的参与,生态时代的发展与生态系统管理。在促进亚洲可持续森林资源管理中,市场工具、社区参与和环境服务都得到了应用。亚洲林业的转型表现出多样化,其森林、社会与环境之间的联系是丰富多彩的。 相似文献
962.
In order to study the changes of plant species diversity along the biotope gradient and its influencing factors in a wetland-arid
grassland ecosystem in the arid and semi-arid regions of northwest China, four transect lines were set along the biotope gradient
in four directions: east, northeast, west and northwest, and altogether 123 sample plots were investigated on species composition,
density, foliage cover, height and biomass (calculated in fresh weight). The whole study area was divided into the wetland
zone, the ecotone and the arid grassland zone in terms of habitat characteristics and vegetation types. In this paper, we
analyzed and compared the species diversity in the ecotone of a wetland-dry grassland ecosystem in Yanchi County, Ningxia
Hui Autonomous Region, with the help of biodiversity software BioDiversity Pro and statistical software Microcal Origin, as
well as the combined measurement of species diversity indices. The results revealed distinct differences between those three
vegetation zones along each transect line. The ecotone had the highest richness indices (R) and comprehensive diversity indices (Y), reflecting the edge effect. The greatest evenness indices (E) were found in the arid grassland zones. This result agreed with the phenomenon of desertification reversion, vegetation
restoration and dominant communities’ formation. As for the four transect lines, the east and the northeast scored higher
in each diversity index than the others due to less human disturbance, gentler topography uplift and more intercepted materials
and energies. The highest Simpson index value was found in the northeast transect line, which was 39.9% higher than the lowest
in the Northwest.
Translated from Journal of Beijing Forestry University, 2006, 28(5): 12–17 [译自: 北京林业大学学报] 相似文献
963.
Growth,carbon sequestration,and management of native tree plantations in humid regions of Costa Rica
Alvaro Redondo-Brenes 《New Forests》2007,34(3):253-268
The Costa Rican government has provided incentives for reforestation programs since 1986 and initiated a Payment for Environmental
Services program in 1996. These incentives yielded native species reforestation programs throughout the country. This research
aims to provide information about growth, carbon sequestration, and management of seven native tree species (Vochysia guatemalensis, Vochysia ferruginea, Hyeronima alchorneoides, Calophyllum brasiliense, Terminalia amazonia, Virola
koschnyi, and Dipteryx panamensis) growing in small and medium-sized plantations in the Caribbean and Northern lowlands of Costa Rica. A total of 179 plots
were evaluated in 32 farms. Overall, I found that V. guatemalensis, V. ferruginea, H. alchorneoides, and T. amazonia were the species with the fastest diameter, total height, and volume growth; and T. amazonia and D. panamensis sequestered more carbon. Moreover, I found that the plantations that had been thinned before this assessment had the best growth. The results of the
present research enhance the criteria elaborated in previous research findings to improve species choices for reforestation
and silvicultural management in Costa Rica and in other regions with similar ecological features. Furthermore, they support
the concept that tropical plantations can serve diverse economic, social, and ecological functions that may ultimately help
reduce atmospheric CO2 accumulation. 相似文献
964.
965.
全球变化样带研究是IGBP的研究热点.生态系统定位研究站是进行样带研究的基础和依托.本文从样带理念出发,在国内首次将长江流域25°~35° N范围定义为中国南部东西样带(WETSC),并探讨了中国南部东西样带(WETSC)范围内森林生态站的构建和布局模式;同时引进国外定位研究中先进的从Station到Site的理论,在江西省赣江流域提出了从南亚热带向中亚热带过渡区到中亚热带向北亚热带过渡区的九连山-井冈山-大岗山-庐山小样带;在新疆维吾尔族自治区北部提出了从北向南建立阿尔泰山-额尔齐斯河-准噶尔盆地-天山小样带;同时从大城市群生态系统服务功能出发,在广东省珠江三角洲内提出了广州-番禺-中山-珠海-澳门和广州-东莞-深圳-香港的三角形小样带. 相似文献
966.
S. H. R. Sadeghi T. Mizuyama S. Miyata T. Gomi K. Kosugi S. Mizugaki Y. Onda 《Journal of Forest Research》2007,12(4):270-277
The reforested headwater watersheds in Japan are very important from the points of view of commercial and environmental aspects.
At the present time, much and varied research is running to assess and understand the hydrologic behavior of these watersheds.
The present study was conducted to evaluate the applicability of the deterministic model MUSLE in the Mie small steeply reforested
watershed. The model was tested and calibrated using accurate continuous suspended sediment data collected during eight storm
events in 2004. Results of the original model simulations for storm-wise sediment yield did not match the observed data, while
the revised version of the model could imitate the observed values well. The results of the study approved the efficient application
of the revised MUSLE in estimating storm-wise sediment yield in the study area with a high level of agreement of beyond 88%,
an acceptable estimation error of some 14% and non-significant difference in mean values. 相似文献
967.
森林生态体系的建立,是发挥森林生态效益的必要物质条件,是调节人类生存环境的载体和加湿器。笔者以太原市森林资源的数量和质量统计数据为基础,从森林类型、树种组成、龄组组成、森林起源、林种组成5个方面进行统计分析,提出了森林经营及森林生态体系构建的措施。 相似文献
968.
本文通过逻辑推论,提出了一个计算森林生态系统蒸发散的理论公式。经过初步检验,证明这一公式是可行的,适于对不同土地利用类型进行蒸发散的计算。 相似文献
969.
以天津设施种植业为例,在实地调研和问卷调查的基础上,运用二项逻辑斯谛回归模型分析了都市农业农户对科技信息服务需求意愿的影响因素。研究结果表明:农户对科技信息服务的需求大,同时,农户特征因素(学历)、技术诱导因素(家庭收入、设施类型、长期种植人数)、信息来源因素(信息渠道多样性、参加培训讲座次数)、农户主观因素(废物处理技术关注度、优质化肥农药关注度)均对农户科技信息服务需求有显著影响。据此提出组建多元化的农业科技信息服务队伍,兼顾信息服务内容的实用性与前瞻性,创新多层、多维的信息服务模式等对策建议。 相似文献
970.
Ecosystem services imply the natural environmental conditions and their effectiveness formed and sustained by ecosystems and ecological processes. From the view of city planning, in this paper, the evolution of the conception of ecological service-value and the relationship between the ecological service-value and city planning are reviewed. At the same time, it raised a conception about ecological space service value and negative ecological effect and an innovation proposal on city planning is presented. 相似文献