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51.
湖北省土地资源遥感调查与评价 总被引:4,自引:1,他引:3
根据1999年TM影像解译了湖北省土地利用现状,然后以土地利用现状图为基础,采用地理信息系统技术,结合湖北省的实际情况,选择土壤、地形、坡度等评价因子,对湖北省土地资源进行了适宜性评价,简要地将全省土地资源划分为九等。评价结果表明:湖北省水热条件好,土地适宜性广,宜农林牧业同时利用的土地广泛分布;但是该省的基本农田面积小,土地垦殖率高,低产田面积大,后备耕地资源严重不足;土地利用结构与土地资源的供给条件、利用要求不相适宜,利用效益末得到充分发挥。 相似文献
52.
On-going population growth and resulting domestic demand for water require rapid and effective decision-making as regards groundwater management and control of the various sources of salinization and pollution in Coastal aquifers. Sustainability of water resources for utilization by future generations must therefore be a high priority, not only for the purpose of fulfilling needs for water usage but also for bringing people into harmony with their ambient natural environment.The objective of this paper is to propose an empirical approach for prioritization of the needs involved for sustainable aquifer management. The approach involves a schematic format to:(1) develop a global understanding of an aquifer's hydrological and environmental properties in order to delineate appropriate eco-hydrological scenarios and recommend corresponding operational management activities; and(2) emphasize the importance of educating and increasing the awareness of the population involved as to the need for and viability of socially acceptable measures for sustainable management of groundwater and other resources.The psychologist Abraham Maslow utilized a pyramid to illustrate that until people's most basic needs were fulfilled, higher levels of needs would remain irrelevant. This paper postulates a comparable pyramid prioritizing hydrological needs required for progressing towards sustainable groundwater resources. Two sub-regions of Israel's Coastal aquifer in the Sharon region have been presented as representative areas, each characterized by different stress of exploitation. In assessing these sub-regions situation, specific measures have been recommended for achieving and/or maintaining sustainable groundwater resources in light of the ambient environment, and the level of the population on the pyramidal hierarchy of groundwater needs. 相似文献
53.
母岩的风化剥蚀速率与土壤允许流失量的关系 --以长江三峡坝区风化花岗岩土壤为例 总被引:5,自引:0,他引:5
土壤允许流失量的确定是一个非常复杂而又必须解决的问题,它关系到水土保持措施的布设和土壤的可持续利用。然而,发育在不同母质上的土壤,其土壤的最大允许流失量差异很大,确定这一值的依据也各不相同。在岩成土壤地区,母岩风化剥蚀速率的大小直接影响土壤的发育。是确定土壤允许流失量、分析人类加速水土流失的重要依据之一。选长江三峡黄陵背斜段风化花岗岩土壤为研究对象,根据剥蚀沉积相关原理,通过恢复古地理环境及时代,计算出新生代以来本区花岗岩的平均风化剥蚀速率为16.97mm/ka.最大剥蚀速率为49.56。又根据区内太平溪流域的泥沙资料,算出了当地现代的剥蚀速率,多年平均为297.7mm/ka,最小值为31.5mm/ka,而水利部颁布的当地土壤允许流失量为200t/km^2,a,折合为76.9mm/ka,二者相差近1.5—4.5倍。基于此。提出了确定土壤允许流失量必须参考母岩风化剥蚀速率的新观点。 相似文献
54.
长江三峡地区坡地发育初步研究 总被引:8,自引:2,他引:6
坡地发育是地貌学研究的基本问题之一。三峡地区坡地发育的研究对三峡库岸稳定性的评估和三峡移民的土地开发具有十分重要的意义。首先从概括坡地发育的研究进展,阐述科学家们对坡地发育的不同看法入手,引出三峡地区坡地发育的特殊性。初步研究三峡地区的坡地发育具有分段式分进的特点,包括中山峰陡坡的剥蚀后退过程,山顶缓坡的风化剥蚀夷平的过程,上段斜坡的片流坡地侵蚀过程,下段陡坡的剥坡后退过程,山麓堆积缓坡的剥蚀过程等。通过分析三峡地区坡地的五种坡段的成因、现状、发展趋势以及它们对三峡库区的稳定性和三峡移民的土地开发的影响,预测未来的三峡库岸,大部分为剥蚀陡坡,部分为崩塌滑坡陡坡,三峡沿岸城镇开发建设的重点将是库岸有坡地的防护工程。 相似文献
55.
生态社区综合评价指标体系的初步探讨 总被引:14,自引:0,他引:14
生态社区的出现和发展一直广受关注,建立生态社区综合评价指标体系对于生态社区的实践和发展具有重要的意义。本文通过对社区可持续发展理论,生态平衡理论以及生态社区本身系统特点的探讨,尝试建立一个综合评价指标体系,同时对评价指标体系应体现的功能,以及评价指标体系构建的原则做了初步探讨。 相似文献
56.
The main purpose of this study is to assess economic vulnerability of small island development regions as part of their sustainability constraints. By combining economic and environmental time series data, we assessed a composite index of economic vulnerability which is constructed from three exogenous variables, namely economic exposure, economic remoteness, and economic impact of environmental and natural disasters. We used the Amami Islands, Kagoshima Prefecture, Japan as the case studies for this paper.The results indicated that using a gross island products based valuation index, Kikaijima is the most vulnerable island in the Amami Islands with a composite economic vulnerability index (CEVI) value of 0.678, while by using a per capita based index, Okinoerabujima is considered the most vulnerable island with a CEVI value of 0.680. From the results we also revealed that smaller islands have relative higher vulnerability than the bigger one, which also confirms some previous country-level vulnerability studies.However, it is matter of fact that some islands that have relatively high vulnerability also have good economic performance as shown by their per capita income. In this regard, it can be argued that the success of these small islands could have been achieved in spite of and not because of their inherent vulnerability conditions as an indicator of sustainability constraint. Regarding these findings, we also examined a comparison between vulnerability results and the preliminary concept of an island's resilience in order to capture another perspective on sustainability assessment in a small island region. 相似文献
57.
Zhang Jing Feng Zhiming Yang Yanzhao 《中国人口.资源与环境(英文版)》2006,4(2):33-40
The article puts forward the process and means of regional water and land balance research, and then from two scenarios which are the balances under natural regulation and human intervention, calculated and analysed the balance between water and land on Ningxia Plain. For the balance under natural regulation named farmland water balance, using farmland water resource balance equation, the research estimated the monthly farmland" water balance of 8 major crops for all of the 12 counties on Ningxia Plain in the period of 1960-2001; for the balance under human intervention, the research estimated land-use water balance equation of the counties in 2000, and calculated the balance between land use and water resources including irrigating water of all the 12 counties on Ningxia Plain. Results showed that ①precipitation can not meet the water demand of the crops for growth and development on Ningxia Plain, and water shortage is the primary character of farmland water balance under natural regulation. ②the diversity of water and land balance of different counties is distinctly influenced by the crop structure, water quantity for irrigation and irrigation level. ③Irrigation water could meet the crop water demand on Ningxia Plain in 2000, but there was not much space to expand irrigating cultivated land. 相似文献
58.
Methodological Basis of Ecological Safety Standards for the Technogenic Impact of Mineral Resource Exploitation 总被引:1,自引:0,他引:1
A new methodological approach to the development of biological and technological safety standards for the impact of underground mining on the natural biota is proposed. 相似文献
59.
Whereas past research has treated co-management of common pool resources as if villagers and project implementing authorities
were the only relevant actors, numerous external factors beyond the control of these two partners create barriers to successful
co-management. This paper draws on discussions with Forest Department officials to examine the influence of these forces on
the outcomes of Joint Forest Management (JFM) in Tamil Nadu, India. An empirical inquiry into the operational aspects of JFM
indicates the important roles of political parties, powerful people, and other state institutions and functionaries as well
as the flow of foreign funding. Further, the strong demand by local people for socio-economic development interventions as
opposed to improvement of degraded forests belittles the role of the Forest Department relative to other departments. Numerous
other conditioning factors and relationships are explored. The authors call for reforms in public governance to allow better
participation of all the actors involved for this participatory management approach to succeed and sustain. 相似文献
60.
N. O. Kin 《Russian Journal of Ecology》2008,39(4):254-260
Heavy metal accumulation by plant communities has been studied in different zones of impact of gas field development. The contents of heavy metals in different blocks of plant communities has proved to depend not only on the location of phytocenosis but also on its species composition. Communities dominated by species of the family Poaceae contain smaller amounts of heavy metals than those dominated by species of the family Asteraceae, especially of the genus Artemisia. The order of precedence in the accumulation of heavy metals in different blocks of plant communities has been revealed. 相似文献