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41.
环境伦理与区域可持续发展(英文)   总被引:2,自引:1,他引:1  
The scientific environmental ethics plays a key role in the recognition of the human-environment interactions. Modern environmental ethics is the philosophical re-thinking of modern human race environmental behavior. The development of environmental ethics theory, as well as its application in reality, determines the viewpoints of environmental ethics. Sustainable development implies harmony on human-environment interactions and inter-generation responsibility, with emphasis on a harmonious relationship among population, resources, environment and development, so as to lay a sustainable and healthy foundation of resources and environment for future generations. The harmonious society construction in China that is raised by the Chinese central government should be covered by environmental ethics. The connotation of open environmental ethics includes a respect for nature, care for the individual human race, and respect for the development of future generations, which means giving consideration to natural values, individual and human race benefits and welfare across generations. The role of environmental ethics in regional development consists of cognition, criticism, education, inspiration, adjusting, legislation and promoting environmental regulations. The major problems in regional development are extensive resource exploration, fast population growth, irrational industrial structure, unfair welfare distribution and the twofold effects of science and technology development. The formulation of environmental ethics that aims at regional sustainable development, can not only harmonize the relationship of population, resource, environment and economic development, but also guide behavior selection, push social and political system transformation, strengthen the legal system, and raise environmental awareness of the public.  相似文献   
42.
China’s southwestern special terrain pattern as parallel arrangement between longitudinal towering mountains and deep valleys has significant effects on the differentiation of local natural environment and eco-geographical pattern in this region.The 1:50,000 Digital Elevation Model(DEM) data of Longitudinal Range-Gorge Region(LRGR),meteorological observation data from the station establishment to 2010,hydrological observation data,Normalized Difference Vegetation Index(NDVI) and Net Primary Productivity(NPP) products of MOD13 and MOD17 as well as 1:1,000,000 vegetation type data were used.Moisture indices including surface atmospheric vapor content,precipitation,aridity/humidity index,surface runoff,and temperature indices including average temperature,annual accumulated temperature,total solar radiation were selected.Based on ANUSPLIN spline function,GIS spatial analysis,wavelet analysis and landscape pattern analysis,regional differentiation characteristics and main-control factors of hydrothermal pattern,ecosystem structure and function in this region were analyzed to reveal the effects of terrain pattern on regional differentiation of eco-geographical elements.The results show that:influenced by terrain pattern,moisture,temperature and heat in LRGR have shown significant distribution characteristics as intermittent weft differences and continuous warp extension.Longitudinal mountains and valleys not only have a north-south corridor function and diffusion effect on the transfer of major surface materials and energy,but also have east-west barrier function and blocking effect.Special topographic pattern has important influences on vegetation landscape diversity and spatial pattern of ecosystem structure and function,which is the main-control factor on vegetation landscape diversity and spatial distribution of ecosystem.Wavelet variance analysis reflects the spatial anisotropy of environmental factors,NDVI and NPP,while wavelet consistency analysis reveals the control factors on spatial distribution of NDVI and NPP as well as the quantitative relationship with control degree.Special terrain pattern in LRGR is the major influencing factor on eco-geographical regional differentiation in this region.Under the combined effect of zonality and non-zonality laws with "corridor-barrier" function as the main characteristic,special spatial characteristics of eco-geographical regional system in LRGR is formed.  相似文献   
43.
有益组份及有害元素含量的多寡,是进行矿床經济地質評价的主要依据。而能否真实地反映这一客观情况,又主要取决于化学取样及化学分析的合理性和正确性。“地質与勘探”1958年第三期与本期連續发表了五篇化学取样方面的文章,分別就化学取样方法的选择、样品的合併等问题进行了探討,并介绍了有关单位的实际经驗,我們認为这是必要的。几年来,随着地質勘探水平的提高,化学取样工作也有了很大的改进与提高,为評价矿床,圈定矿体,划分儲量級別和計算儲量提供了有力的依据,保证了儲量报告的完整性。但是,在化学取样工作中也还存在一些问题。例如,有的单位的化学取样工作沒有根据不同矿床的特性,合理地选择取样方法,尽量采用更簡易、更經济的方法达到取样的目的;有的在规格和间距方面,缺乏系統地試驗研究,还有的取样的目的性不明确,在佈置样品时不够慎重,使许多样品失去了实际作用。此外,由于样品管理不善,人为的造成返工补课,造成浪  相似文献   
44.
岩心鑽探的目的是要了解鑽进地段的地質或矿层的情况,探明矿床及圍岩的構造、厚度及其質量变化情况。因此鑽探除了要获得各个地层或矿体的岩心資料外,还必須正确地提供其存在的空间位置,只有这样才能保证儲量計算的准确性。显然,每一个鑽孔的傾角和方位角是否符合地質設計要求,这和岩矿心采取率的高  相似文献   
45.
The Forest Landscape Model(FLM) is an efficiency tool of quantified expression of forest ecosystem’s structure and function. This paper, on the basis of identifying FLM, according to the stage of development, summarizes the development characteristics of the model, which includes the theoretical foundation of mathematical model, FLM of stand-scale, primary development of spatial landscape model, rapid development of ecosystem process model as the priority, and developing period of structure and process driven by multi-factor. According to the characteristics of different FLMs, this paper classifies the existing FLM in terms of mechanism, property and application, and elaborates the identifications, advantages and disadvantages of different types of models. It summarizes and evaluates the main application fields of existing models from two aspects which are the changes of spatial pattern and ecological process. Eventually, this paper presents FLM’s challenges and directions of development in the future, including:(1) more prominent service on the practical strategy of forest management’s objectives;(2) construction of multi-modules and multi-plugin to satisfy landscape research demand in various conditions;(3) adoption of high resolution’s spatial-temporal data;(4) structural construction of multi-version module;(5) improving the spatial suitability of model application.  相似文献   
46.
以土地利用变化和气候变化为特征的全球和区域环境变化及其影响已经成为国际社会和公众关注的焦点,同时也是土地科学、全球变化科学和全球生态学关注的关键问题。由于土地、气候和森林生态系统之间存在着复杂而密切的关系,土地利用变化和气候变化将不可避免地对森林结构和功能产生重要影响。如何采用合理的适应措施降低这些变化可能带来的损失,是目前全球变化研究亟待解决的问题之一。因此,研究土地利用和气候变化对森林的单独及综合影响具有重要的科学意义。本文综合利用基于主体的土地利用模型(ABM/LUCC)、生态系统过程模型(PnET-II)以及森林景观动态模型(LANDIS-II)构建了综合模拟研究框架,选择森林类型多样且具有长期观测数据积累的江西省泰和县为研究区,模拟并对比了土地利用和气候变化组合情景下未来森林地上总生物量的变化差异。结果表明:① 土地利用变化对泰和县森林地上总生物量的影响比气候变化所带来的影响更加显著。研究区森林地上总生物量在有土地利用变化干扰的情景下与RCP 2.6、RCP 4.5和RCP 8.5单独的气候情景下相比分别减少33.13%、32.92%和32.42%;② 尽管未来气候变化可能有利于森林地上总生物量的积累,但土地利用变化将使森林地上总生物量显著减少,并将抵消气候变化带来的正效应;③ 本文提出的综合模拟研究框架可以很好地模拟土地利用和气候变化对森林生态系统的影响,可为提升和优化人工林结构和功能、开展可持续森林管理提供科学建议。  相似文献   
47.
过去50年气候变化下中国潜在植被NPP的脆弱性评价   总被引:4,自引:1,他引:3  
借助动态植被模型IBIS,首先模拟了过去50年(1961-2010年)气候变化下中国潜在植被NPP的动态变化,然后采用IPCC第五次评估报告选定的标准气候态时段(1986-2005年)平均气候状态作为“标准年气候”,并将该气候条件下的潜在植被NPP作为评价基准。通过与基准进行比较,计算每一年潜在植被NPP的波动情况,进而评价该年的气候条件是否使潜在植被“不适应”以及“不适应”的程度,最后根据过去50年的“不适应”次数和程度综合判断气候变化下潜在植被NPP的脆弱性。评价结果显示:在过去50年的气候变化下,天山以南的暖温带荒漠生态系统、北方温带草原生态系统以及青藏高原西部的高寒草原生态系统更容易受到气候变化的不利影响,NPP呈现出较高的脆弱性;而大部分以森林为主的生态系统则不容易受到气候变化的影响,NPP脆弱性较低,其中以常绿阔叶林和针叶林为主的生态系统NPP脆弱性更低。此外,天山以北的温带荒漠生态系统以及青藏高原中部和东部的高寒草原草甸生态系统NPP也呈现出较低的脆弱性。  相似文献   
48.
The tradeoffs and optimizations of ecosystem services are the key research fields of ecology and geography.It is necessary to maximize the overall benefit of timber production and carbon storage for forest ecological development in China.We selected the Huitong National Research Station of Forest Ecosystem as our study area,and used In VEST model to evaluate timber production and carbon storage quantitatively.The results showed that:(1)While timber production increased with harvesting intensity over the planning horizon,carbon storage decreased.There were tradeoffs between timber production and carbon storage according to the significant negative relationship.(2)While the overall benefit of timber production and carbon storage increased with harvesting intensity,the value of tradeoffs decreased.T1 and T2 scenarios,with harvesting intensity of 10%–20% every 10 years,are the optimum management regimes for the two ecosystem services to gain more benefit and less tradeoffs.(3)The current harvesting intensity in Huitong County was slightly higher than the optimum harvesting intensity.On practical dimension,these findings suggested that obvious objectives are needed to formulate the corresponding countermeasures of tradeoffs,in order to realize the improvement of ecosystem services and the optimization of ecosystem structures.  相似文献   
49.
吴卓  戴尔阜  林媚珍 《地理研究》2018,37(11):2141-2152
在全球气候变化和人类活动的影响下,森林生态系统结构、功能以及空间格局都将发生不同程度的变化。明晰景观尺度上未来森林的动态变化,对森林可持续发展具有重要意义。选择江西省泰和县为研究区,综合利用土地利用模型(CA-Markov)和森林景观动态模型(LANDIS-II),并结合生态系统过程模型(PnET-II),模拟气候变化、土地利用、采伐以及综合情景下未来40年(2010-2050年)阔叶林、针叶林的面积及生物量变化。结果表明:① 气候变化对森林面积影响较小,采伐使森林面积显著减少,土地利用变化使森林面积的变化更加剧烈;② 针叶林和阔叶林对不同干扰方式的响应表现出较强差异,针叶林对采伐的响应更加剧烈;③ 多模型综合模拟方法有助于区域森林管理,为南方红壤丘陵区森林结构优化和功能提升提供科学建议。  相似文献   
50.
土地系统多主体模型的理论与应用   总被引:1,自引:0,他引:1  
戴尔阜  马良  杨微石  王亚慧  尹乐  童苗 《地理学报》2019,74(11):2260-2272
土地变化科学是理解人类—自然耦合系统的交叉学科研究方向。多主体模型(ABM)作为过程导向模型,对揭示土地变化驱动力,理解土地变化过程有重要作用。本文从理论、应用与建模框架三方面出发,总结了ABM理论基础和相关概念;阐述了ABM在城市和农业土地系统两方面的应用与发展,进一步介绍了横断山区退耕还林ABM研究案例;在梳理ABM建模协议的基础上,提出了主体视角的土地系统ABM建模框架和实施流程。在城市土地利用方面,ABM研究从最初基于景观研究城市扩张,到研究城市内部居住分隔,规划分区,生态功能等多方面;在农业土地利用方面,ABM应用则呈现出更加多样化和个性化的特征,包括农民行为、农户决策、种植系统、农业政策等。相比于传统模型,ABM因其依靠本地知识与数据而使得其构建更为复杂,且不易推广;但因其独特的自下而上模型构架,在探究土地变化驱动力、刻画人类行为对自然环境影响等方面具有不可或缺的作用。  相似文献   
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