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热区山地轮歇垦殖与替代技术的初步探讨 被引量:1
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作者 李一鲲 李荣春 《云南热作科技》 1995年第3期19-25,共7页
热区山地轮歇垦殖与替代技术的初步探讨李一鲲,李荣春(云南省农垦总局科技处)生态系统中生物生存、生长所需的光、热、气、水、肥各因素,除日光、大气直接影响生物外,各因素均受土壤状况的影响或制约,从而土壤成为生态系统中重要... 热区山地轮歇垦殖与替代技术的初步探讨李一鲲,李荣春(云南省农垦总局科技处)生态系统中生物生存、生长所需的光、热、气、水、肥各因素,除日光、大气直接影响生物外,各因素均受土壤状况的影响或制约,从而土壤成为生态系统中重要的物质基础,是生态系统中物质能量循... 展开更多
关键词 热区山地 轮歇垦殖 耕作制度
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云南热区山地资源可持续开发利用的探讨
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作者 李一鲲 《热带农业科技》 2004年第2期21-25,共5页
论述了云南热区“轮歇垦殖”与种植橡胶树对山地资源和生态环境的影响,提出热区山地资源开发利用应以经济林或混农林业为主,既利用又保护,使生态与经济效益最佳结合,促进可持续发展。
关键词 热区山地 资源利用 云南
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云南热区农业生态环境与山地型农业生产体系建设的探讨 被引量:1
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作者 李一鲲 洪龙汉 《云南热作科技》 1999年第3期18-22,共5页
以“现代集约持续农业”为指导思想,以保土、保肥为关键,开发与保护并重,在云南热区山地建立经济林或混农林业为主体的山地型农业生产体系。为实现这一目标,必须加强领导,深入调查资源现状,统一规划,提高人的素质,加强农业生产... 以“现代集约持续农业”为指导思想,以保土、保肥为关键,开发与保护并重,在云南热区山地建立经济林或混农林业为主体的山地型农业生产体系。为实现这一目标,必须加强领导,深入调查资源现状,统一规划,提高人的素质,加强农业生产社会服务体系建设,制订稳定的经济政策和增加建设资金,总结经验。 展开更多
关键词 热区山地 农业生产体系 云南
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Land cover change and carbon stores in a tropical montane cloud forest in the Sierra Madre Oriental,Mexico 被引量:4
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作者 Edgar G.LEIJA-LOREDO Numa P.PAVóN +2 位作者 Arturo SáNCHEZ-GONZáLEZ Rodrigo RODRIGUEZ-LAGUNA GregorioáNGELES-PéREZ 《Journal of Mountain Science》 SCIE CSCD 2018年第10期2136-2147,共12页
Tropical montane cloud forest is one of the ecosystems with the highest biomass worldwide, representing an important carbon store. Globally its deforestation index is –1.1%, but in Mexico it is higher than –3%. Carb... Tropical montane cloud forest is one of the ecosystems with the highest biomass worldwide, representing an important carbon store. Globally its deforestation index is –1.1%, but in Mexico it is higher than –3%. Carbon estimates are scarce globally, particularly in Mexico. The objective of this study was to simulate future land-cover scenarios for the Sierra Madre Oriental in Mexico, by analyzing past forest cover changes. Another objective was to estimate stored carbon in the two study areas. These objectives involve the generation of information that could be useful inputs to anti-deforestation public policy such as the REDD+ strategy. Remote sensing was used to measure land cover change and estimate carbon stocks. Satellite images from 2015, 2000 and 1986 were used, and Dinamica EGO freeware generatedmodels of future projections. Between 1986 and 2015, 5171 ha of forest were converted to pasture. The annual deforestation rates were –1.5% for Tlanchinol and –1.3% for the San Bartolo Tutotepec sites. Distance to roads and marginalization were highly correlated with deforestation. By 2030, an estimated 3608 ha of forest in these sites will have been converted to pasture. Stored carbon was estimated at 16.35 Mg C ha-1 for the Tlanchinol site and 12.7 Mg C ha-1 for the San Bartolo site. In the Sierra Madre Oriental deforestation due to land cover change(–1.4%) is higher than levels reported worldwide. Besides having high values of stored carbon(14.5 Mg C ha-1), these forests have high biodiversity. The models' outputs show that the deforestation process will continue if action is not taken to avoid the expansion of livestock pasturing. This can be done by paying incentives for forest conservation to the owners of the land. The results suggest that REDD+ is currently the most viable strategy for reducing deforestation rates in tropical montane cloud forests in Sierra Madre Oriental. 展开更多
关键词 Cloud forest Carbon stores C mitigation Climate change Dinamica EGO Forest management Remote sensing.
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Distribution of Soil Nutrients in Arable Land of Tropical Hilly and Mountainous Area
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作者 刘存法 王汀忠 《Agricultural Science & Technology》 CAS 2016年第7期1648-1650,1653,共4页
[Objective] The aim was to explore spatial distribution characters of soil nutrients in arable lands of Hainan mountainous areas and provide references for soil nutrient management in tropical mountainous areas. [Meth... [Objective] The aim was to explore spatial distribution characters of soil nutrients in arable lands of Hainan mountainous areas and provide references for soil nutrient management in tropical mountainous areas. [Method] The research took arable lands in Wuzhishan City as an example by field survey, sampling and lab analysis and investigated soil nutrients and distributions based on analysis of soil nutrient contents. [Result] The soils were dominated by acid soils, with pH of 5.1; soil nutrients were distributed in a non-uniform manner; contents of soil organic matter, available phosphorus, available potassium, as well as medium elements kept lower or moderate levels; effective copper and available zinc were rich. Local spe- cial climate, uneven distribution of parent material and non-uniform fertilization con- tributed to acid soils and unbalanced distribution of soil nutrients in Wuzhishan. [Conclusion] It is recommended to facilitate soil nutrient balance by promoting re- turning straws to farmlands and technical specification of balanced fertilization by soil testing as per nutrient distribution of arable lands in Wuzhishan City. 展开更多
关键词 Tropical area Arable land Soil nutrients Hilly and mountainous area
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Changes in Streamflow Regime Due to Anthropogenic Regulations in the Humid Tropical Western Ghats, Kerala State, India
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作者 ABE George ERINJERY JOSEPH James 《Journal of Mountain Science》 SCIE CSCD 2015年第2期456-470,共15页
Regulation of streamflow by a reservoir creates a flow regime much different from the preimpoundment period flow regime. Hydro-Electric Projects(HEPs) commissioned in the Western Ghat regions of the Kerala State, Indi... Regulation of streamflow by a reservoir creates a flow regime much different from the preimpoundment period flow regime. Hydro-Electric Projects(HEPs) commissioned in the Western Ghat regions of the Kerala State, India during the last four decades caused considerable changes in the flow regimes of the rivers of the Kerala State in southwest India. In this paper, the Indicators of Hydrologic Alteration(IHA) approach proposed by Richter et al.(1996) is used to analyze flow regime changes in the Periyar and Muvattupuzha Rivers, due to the construction of the Idukki(1976), Idamalayar(1987) and Lower Periyar(1997) HEPs in the high ranges of the Western Ghats. Normal rainfall years(annual rainfall values within mean ± 0.75 standard deviation limits) are only considered in the analysis to focus on hydrologic alterations due to human activities. The mean hydrologic alteration in the Periyar River(deviation from the pre-development hydrologic indicator values) after commissioning of three HEPs is 35%. Inter-basin water transfer after power generation from the Idukki HEP resulted in a higher discharge in the adjacent Muvattupuzha River, leading to considerable changes in the hydroenvironment(mean hydrologic alterations varying between 57 to 63%). IHA parameters showing hydrologic alterations above the 67 th Percentile werefurther analyzed. For each of the pre-construction hydrologic parameters ± 1 standard deviation from the mean is set as the upper and lower management target limits. The values of each IHA parameter beyond these targets are considered as nonattainment. Considerable hydrologic alterations are observed, especially for low flows in both basins. Inter-basin transfer induced larger changes in flow parameters compared to intra-basin regulations. The study shows that under a proper water release and diversion scheme, the non-attainment of IHA parameters(values fall beyond the target limits) can be reduced. The findings of the study will be greatly beneficial to regional water management and restoration of an eco-environmental system in the humid tropical region. 展开更多
关键词 Range variability approach Hydroelectric projects Humid tropics Flow regime changes Inter-basin regulation Intra-basin regulation
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