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111.
112.
研究了美国国际集团(AIG)注资新疆昌吉玛纳斯等3县开展温室气体减排项目的推进过程.这是在中国成功开展的第一例农业温室气体自愿减排项目,该项目共减排温室气体21×104t CO2当量.主要通过农户沼气推广、沙漠防沙林种植、农业滴灌灌溉等项目,达到温室气体减排、节约能源、防沙造林、改善当地的生态环境、增加农民收入等目的.... 相似文献
113.
荒漠交错带开发利用研究——以新疆于田绿洲为例 总被引:3,自引:0,他引:3
绿州—荒漠交错带是一个生态环境脆弱带 ,由于其自然系统发育的先天不足 ,加上人类的开发活动 ,经济发展与生态环境保护矛盾进一步加剧 ,已成为影响绿洲发展的一个重要方面。本文以于田绿洲为例 ,通过分析于田绿洲荒漠交错带的开发利用现状 ,提出相应的交错带生态环境建设的建议和保护措施。 相似文献
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115.
Evaluation of oasis ecosystem risk by reliability theory in an arid area: A case study in the Shiyang River Basin, China 总被引:2,自引:0,他引:2
Ecosystem risk is a new concept in understanding environmental problems. It is important to study and develop quantitative methods for regional ecosystem risk analysis. In this study, some new indicators and methods for measuring oasis ecosystem risk were established using reliability theory. These indicators are linked to water resource, which is the key restricting factor in arid area oasis ecosystems. They have clear meanings and can also be compared in different arid area oases. A case study in the Liangzhou oasis of the Shiyang River Basin in China shows how to calculate these ecosystem risk indicators. The results of the case study are as follows: the reliability indicator, risk indicator, stability indicator, and integrated loss indicator of the Liangzhou oasis are 0.686, 0.314, 0.743, and 0.301, respectively. This means that the reliability degree of the oasis's ecosystem safety is 68.6%; the degree of risk that it is unsafe is 31.4%; the stability degree is 74.3%; and 30.1% of the oasis's area is supported by over-exploiting underground water and damaging the lower reaches of the ecosystem. This result can be used as a guide in controlling and managing ecosystem risk in the research area. 相似文献
116.
Adaptation of Nitraria sphaerocarpa to wind-blown sand environments
at the edge of a desert oasis 总被引:1,自引:0,他引:1
This study addresses the adaptation of Nitraria sphaervcarpa to blown sand at the edge of a desert oasis with regard to the aspects of soil seed banks, seedlings, and population. Horizontally, the total number of seeds per unit area decreased from the shrub canopy center to intershrub areas, and most seeds were found under shrub canopies. Vertically, the highest proportion of seeds was found at depths of 5-10 cm. The emergence percentage, seedling mass, and seedling height, which were significantly affected by both burial depth and seed size, were highest at the optimal burial depth of 2 cm, and decreased with increasing burial depth in each seed size-class. Although seedling mass was usually greatest for large seeds and least for small seeds at each burial depth, little difference was observed in seedling height at shallow burial depths of 0-3 cm. The population shows a patchy and discontinuous distribution pattern. Population height increases with increasing sand depth. Also the density increases with increasing depth of sand in the desert; however, there is a steady decrease when the depth of sand is more than 100 cm. This result indicates that the depth of sand that is most suitable for the growth of Nitraria sphaervcarpa is 100 cm. The size of the population is significantly correlated with the sand depth, which increases with increasing depth in the desert. 相似文献
117.
Yiming Yang Zhongren Nan Zhuanjun Zhao Zhaowei Wang Shengli Wang Xia Wang Wangqiang Jin Cuicui Zhao 《环境科学学报(英文版)》2011,23(8):1368-1374
A pot experiment was conducted to study the bioaccumulation and translocation of cadmium (Cd) in cole (Brassica campestris L.)
and celery (Apium graveolens) grown in the Cd-polluted oasis soil, Northwest of China. The results showed that Cd in the unpolluted
oasis soil was mainly bound to carbonate fraction (F2) and Fe-Mn oxide fraction (F3). However, marked change of Cd fractions was
observed with increasing soil Cd concentrations, in which the concentration of Cd in F1 (exchangeable fraction), F2 and F3 increased
significantly (p < 0.001 for F1, F2 and F3). The growth of cole and celery could be facilitated by low concentrations of Cd, but inhibited
by high concentrations. The correlation analysis between the fraction distribution coefficient of Cd in the soil and Cd concentration
accumulated in the two vegetables showed that Cd in F1 in the soil made the greatest contribution on the accumulation of Cd in the
two vegetables. The high bio-concentration factor and the translocation factor of Cd in both cole and celery were observed, and Cd
had higher accumulation in the edible parts of the two vegetables. Therefore, both cole and celery grown in Cd-polluted oasis soil
have higher risk to human health. And the two vegetables are not suitable to be cultivated as vegetables consumed by human in the
Cd-polluted oasis soil. 相似文献
118.
119.
公路是促进社会经济发展的重要基础设施,在公路建设促进荒漠环境改善的同时,由于荒漠区生态环境脆弱,公路建设较湿润区易引起环境退化,且生态恢复十分困难。新疆地域辽阔,自然条件复杂,生态系统结构简单且稳定性差,属中国乃至世界上典型的生态环境脆弱区,是中国荒漠面积最大的省区,荒漠环境复杂和类型齐全。荒漠区公路建设的自然环境具有区域生态脆弱,水源短缺,路域土质复杂,环境保护问题多,道路病害较多等特点。公路建设引起的环境退化主要表现在:致使区域植被覆盖度降低,为灾害发生提供有利地貌条件,引起水、土理化性质变差,对路域大气环境造成污染,荒漠区野生动物生存环境变差等6方面。针对荒漠区自然环境特点与公路建设引起的环境退化及成因,提出在公路规划设计、施工、营运3阶段防治公路路域环境退化的17条措施,以保护荒漠区路域环境和保障交通畅通及区域可持续发展。 相似文献
120.
新疆阿尔泰成矿带可可塔勒花岗岩体锆石LA-ICP-MS U-Pb年龄及其地质意义 总被引:1,自引:0,他引:1
新疆阿尔泰成矿带花岗岩发育,其中很多花岗岩与成矿作用有着密切的联系,特别是400Ma左右的岩浆活动是阿尔泰地区一次重要的岩浆成矿活动,阿尔泰许多金属矿床与这一时期的岩浆构造作用有关。本次研究的出露于可可塔勒铅锌矿区的黑云母花岗岩体,其锆石LA-ICPMS U-Pb年龄为(401.8±1.5)Ma,表明可可塔勒花岗岩是阿尔泰成矿带400Ma左右发生的一次重要岩浆构造作用的产物,该黑云母花岗岩体侵入于矿区下泥盆统康布铁堡组火山岩地层中,岩体与围岩接触带附近的围岩蚀变明显,该黑云母花岗岩的侵入以及其后期的岩浆热液活动可能对区内成矿物质的活化、迁移、富集、成矿具有一定的贡献。 相似文献