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101.
关于进一步发展蛟河市旅游业的思考 总被引:1,自引:0,他引:1
近年来,蛟河市森林旅游发展快,形势育人,特别是1995年成立拉法山国家森林公园以来,根据当地特点,在旅游开发、在旅游开发、促销、接待旅游团体等方面下了很大功夫,建立了有特色的民俗村、渡假村等,已基本形成了四大景区十个景点,总投资额达5600多万元,从业人员达2800多人,总产值达12000多万元。 相似文献
102.
Francisco J. Escobedo David J. Nowak John E. Wagner Carmen Luz De la Maza Manuel Rodríguez Daniel E. Crane Jaime Hernndez 《Urban Forestry & Urban Greening》2006,4(3-4):105-114
Santiago, Chile's semi-arid climate and urbanized environment poses a severe limitation for the establishment and maintenance of urban forests. Municipalities, or comunas, are the main stakeholders in the management of Santiago's public urban forests. A tenable hypothesis would be that as the socioeconomic level of a comuna increases, the better the condition of a comuna's urban forest. Unfortunately, there is little comprehensive information on management, public expenditure, and structure of Santiago's public and private urban forests. To examine this hypothesis, Santiago was divided into socioeconomic strata, then using air photo interpretation and stratified field sampling, urban forest structures were quantified by socioeconomic strata. In addition, interview surveys were used to determine municipal urban forest management and expenditures for different public urban forests based on socioeconomic strata. Urban forests in the high socioeconomic strata had fewer public trees, greater tree cover, tree and leaf area density, and leaf area index than lower socioeconomic strata. The percentage of total municipal budget allocated to public urban forest management was consistent among strata, but the total public urban forest budgets were greater in the high socioeconomic strata. Public urban forest structure is related to the socioeconomic strata of Santiago's different comunas. 相似文献
103.
Frauke Ecke Pernilla Christensen Per Sandström Birger Hörnfeldt 《Landscape Ecology》2006,21(4):485-497
Several studies indicate a long-term decline in numbers of different species of voles in northern Fennoscandia. In boreal Sweden, the long-term decline is most pronounced in the grey-sided vole (Clethrionomys rufocanus). Altered forest landscape structure has been suggested as a possible cause of the decline. However, habitat responses of grey-sided voles at the landscape scale have never been studied. We analyzed such responses of this species in lowland forests in Västerbotten, northern Sweden. Cumulated spring densities representing 22 local time series from 1980–1999 were obtained by a landscape sampling design and were related to the surrounding landscape structure of 2.5×2.5 km plots centred on each of the 22 1-ha trapping plots. In accordance with general knowledge on local habitat preferences of grey-sided voles, our study supported the importance of habitat variables such as boulder fields and old-growth pine forest at the landscape scale. Densities were negatively related to clear cuts. Habitat associations were primarily those of landscape structure related to habitat fragmentation, distance between habitat patches and patch interspersion rather than habitat patch type quantity. Local densities of the grey-sided vole were positively and exponentially correlated with spatial contiguity (measured with the fragmentation index) of old-growth pine forest, indicating critical forest fragmentation thresholds. Our results indicate that altered land use might be involved in the long-term decline of the grey-sided vole in managed forest areas of Fennoscandia. We propose two further approaches to reveal and test responses of this species to changes in landscape structure. 相似文献
104.
Urban forests are unique and highly valued resources. However, trees in urban forests are often under greater stress than those in rural or undeveloped areas due to soil compaction, restricted growing spaces, high temperatures, and exposure to air and water pollution. In addition, conditions change more quickly in urban as opposed to rural and undeveloped settings. Subsequently, proactive management of urban forests can be challenging and requires the availability of current and comprehensive information. Geospatial tools, such as, geographic information systems (GIS), global positioning systems (GPS) and remote sensing, work extremely well together for gathering, analyzing, and reporting information. Many urban forest management questions could be quickly and effectively addressed using geospatial methods and tools. The geospatial tools can provide timely and extensive spatial data from which urban forest attributes can be derived, such as land cover, forest structure, species composition and condition, heat island effects, and carbon storage. Emerging geospatial tools that could be adapted for urban forest applications include data fusion, virtual reality, three-dimensional visualization, Internet delivery, modeling, and emergency response. 相似文献
105.
农牧交错带小流域防护林水源涵养功能研究 总被引:2,自引:0,他引:2
文中以内蒙古赤峰市敖汉旗大五家流域内防护林为研究对象,重点研究该流域内不同防护林涵养水源功能的现状,旨在评价不同植被类型水源涵养功能的差异,同时探寻低功能涵养水源型防护林更新改造途径。研究结果表明:不同防护林的土壤理化性质以及涵养水源功能差异明显,华北落叶松白榆混交、杨树柠条混交枯落物的现存量为3.4695~4.8536 t/hm2,最大持水量为64.225~66.125mm;华北落叶松白榆混交的植被类型具有良好的涵养水源能力,为164.563 t/hm2;灌木纯林和灌木混交林在实际调查中表现较差,在今后的森林经营中应考虑营造针阔混交林。 相似文献
106.
107.
壳斗科植物具有丰富花蜜和花粉.2007年4~7月,对云南哀牢山中山湿性常绿阔叶林壳斗科蜜源植物开发利用的潜力进行了初步研究.在该季节,中华蜜蜂可利用的壳斗科植物主要有木果石栎、景东石栎和腾冲栲.3种植物的花期均为50天左右.放置在原始森林林缘蜂群的取蜜量明显高于放置在原始森林内和附近次生林的蜂群.一群放置在林缘、群势为5标准框的中华蜜蜂蜂群,一个花期可以取蜂蜜约5 kg. 相似文献
108.
Nitrogen (N) has great ecological importance, but the biogeographic pattern across forest biomes in China has only recently been explored. Here we conducted a systematic census of leaf C and N following the same protocol to explore the variations of leaf traits, and their possible responses to plant functional types (PFTs) and environmental factors. Results showed that leaf traits varied substantially across biomes, and the relationships of PFTs to climatic factors were stronger than those of PFTs versus soil nutrient proxies, indicating that plant species composition might be a better predictor of plant species distribution with climate than leaf traits. Soil nutrient proxies explained more variation of leaf traits than climate, which demonstrates that leaf traits reflect important aspects of plant responses to soil nutrients. Importantly, partial general linear models analyses found that PFTs showed the greatest direct influence for leaf traits, and climate and soil affected leaf traits mainly through the change in plant species composition rather than having direct impacts. Hence, we concluded that leaf traits were largely controlled by PFTs rather than climate or soil at the biome scale. The results favored the species composition hypothesis, indicating that leaf nutrient concentration is mainly determined by PFTs. 相似文献
109.
按木论自然保护区森林植被分布状况及相应海拔高度设置代表性的土壤剖面(0-80 cm土层),按国颁标准采集样品与测定土壤理化特性。结果表明:(1)土壤容重为0.86-1.38 g.cm-3;土壤总孔隙度为27.66%-44.14%,其中土壤非毛管孔隙度为4.98%-13.22%;土壤通气度为4.67%-13.08%。(2)土壤pH值为6.03-7.45;有机质含量为13.9-120.3g.kg-1;全N为0.81-3.74 g.kg-1;全P为0.21-0.78 g.kg-1;全K为11.62-22.54 g.kg-1。以上表明,广西木论自然保护区森林土壤疏松、通气性能良好;土壤中N、P、K主要养分含量丰富。 相似文献
110.
Yeon Soo Chung Jae Won Song Dae Ho Kim Sook Shin Young Kyung Park Soo Jin Yang Suk Kyung Lim Kun Taek Park Yong Ho Park 《Journal of veterinary science (Suw?n-si, Korea)》2016,17(2):199-206
Limited information is available regarding horse-associated antimicrobial resistant (AR) Escherichia (E.) coli. This study was designed to evaluate the frequency and characterize the pattern of AR E. coli from healthy horse-associated samples. A total of 143 E. coli (4.6%) were isolated from 3,078 samples collected from three national racetracks and 14 private horse-riding courses in Korea. Thirty of the E. coli isolates (21%) showed antimicrobial resistance to at least one antimicrobial agent, and four of the AR E. coli (13.3%) were defined as multi-drug resistance. Most of the AR E. coli harbored AR genes corresponding to their antimicrobial resistance phenotypes. Four of the AR E. coli carried class 1 integrase gene (intI1), a gene associated with multi-drug resistance. Pulsed-field gel electrophoretic analysis showed no genetic relatedness among AR E. coli isolated from different facilities; however, cross-transmissions between horses or horses and environments were detected in two facilities. Although cross-transmission of AR E. coli in horses and their environments was generally low, our study suggests a risk of transmission of AR bacteria between horses and humans. Further studies are needed to evaluate the risk of possible transmission of horse-associated AR bacteria to human communities through horse riders and horse-care workers. 相似文献