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1996年是我国“九五”计划的第一年.这一年,国家提出了农业产业化的要求;人民治黄赢得了50年安澜的成就;《水土保持法》颁布5周年纪念;中国工农红军到达陕北60周年。这些具有历史意义的事件对黄河中游沙棘资源开发利用产生了影响,促进了沙棘事业的发展。1 沙棘资源建设的新进展1996年黄河中游沙棘资源建设的成就得到了中央领导和部委领导的重视,提出了一些新的指示和意见,从而推动了沙棘资源建设的发展。1.11996年迎来了人民治黄50年安澜的巨大成就,但是,黄河防御大洪水的能力继续处在较低的水平。1996年8月郑州花园口站发生7600m~3/s的洪水,相应水位94.78m,比1958年花园口站2230m~3/s相应水位高出0.92m。据考证和调查,1996年8月洪水是100多年来出现的最高洪水位。1996年全国水灾直接经济损失达2200亿元人民币,大江大河的水患仍然是中华民族的心腹之患。治理黄河的泥沙水患得到中央政府的特别重视,沙棘又一次被国家总理提到了治理黄河的议事日程上。《中国水 相似文献
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试论黄土高原地区沙棘能源林的建立及利用 总被引:6,自引:3,他引:6
黄土高原地区能源资源丰富,但农村生活用能却比较紧缺,区内有140个县属于能源资源缺乏区,一年有3~6个月的缺柴期,该地区农村生活用能的解决必须采取综合措施,因地制宜,先易后难,分步实施。从现阶段来看,营造沙棘能源林是一条简单易行、投入少、见效快、符合当地实际情况的途径,具有经济、生产和生态方面的合理性,将有可能成为整治黄土高原地区生态环境的一个突破口,营造沙棘能源林要适地适树、提高整地、采取合理密植、灌草混交和截干造林等技术,开发利用周期以5~7年为宜。 相似文献
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黄河中游生态环境现状分析 总被引:1,自引:0,他引:1
黄河中游地区是我国经济欠发达区域之一,恶劣的生态环境严重影响了当地经济发展。本文就黄河中游水蚀、风蚀和环境污染给本地区及下游造成的不良影响进行了分析 相似文献
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黄河中游的生境与林业生态工程 总被引:2,自引:0,他引:2
本文分析了黄河中游地区的生态环境现状,认为其生境的恶化主要与植被破坏及资源的不合理利用有关。由此提出在未来的林业生态工程建设中应采取的一些对策,供决策部门参考。 相似文献
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初论我国沙棘资源建设区划 总被引:1,自引:0,他引:1
沙棘有相对较广的生态适应性,在我国西部和北部有大量适宜种植沙棘的土地。为使沙棘种植建立在科学的基础上。发挥沙棘的生态和经济效益,必须研究沙棘的种植区域,制定种植区划,指导沙棘资源建设。本文在总结以往研究的基础上,依据相关区划和沙棘的特性,采用温度、水分等自然因子和水土保持、农村经济等经济社会因子将我国适宜发展沙棘的区域划分为6个一级沙棘种植区:松辽河沙棘经济林种植区,海河水系上中游沙棘生态经济林种植区,黄河中上游(黄土高原)沙棘生态经济林种植区,长江上游沙棘生态经济林种植区,蒙新及内陆河沙棘生态林种植区和青藏高原沙棘种质资源保护区。 相似文献
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Impact of vegetation restoration on hydrological processes in the middle reaches of the Yellow River, China 总被引:1,自引:0,他引:1
Sediment discharge from the Yellow River originates mainly from the drainage area between Hekouzhen and Longmen, i.e., the Helong area. Spatial-temporal variations of the vegetation cover in this area during the 1981–2007 period have been investigated using GIMMS and SPOT VGT NDVI data. We have also analyzed the interannual variations in vegetation cover and changes in annual runoff and sediment discharge, the consequences from precipitation change and the Grain for Green Project (GGP). The results show that vegetation cover of the Helong area has increased during the 1981–2007 period. The northwestern part the Helong area, where the flat sandy lands are covered by grass, has experienced the largest increase. The region where the vegetation cover has declined is largely found in the southern and southeastern Helong area, which is a gullied hilly area or forested. Although precipita-tion was relatively low during the 1999–2007 period, the vegetation cover showed a significant increase in the Helong area, due to the implementation of the GGP. During this period, the most significant improvement in the vegetation cover occurred mainly in the gullied hilly areas of the Loess Plateau, such as the drainage basins of the Kuyehe and Tuweihe rivers and the middle and lower reaches of the Wudinghe and Yanhe rivers. A comparison of the average annual maximum NDVI between the earlier (1998–2002) stage and the next five years (2003–2007) of the GGP indicates that the areas with increases of 10% and 20% in NDVI account for 72.5% and 36.4% of the total area, respectively. Interannual variation of annual runoff and sediment discharge shows a declining trend, especially since the 1980s, when the decrease became very obvious. Compared with the 1950–1969 period, the average runoff during the 1980–2007 period was reduced by 34.8×108 m3 and the sediment discharge by 6.4×108 t, accounting for 49.4% and 64.9% of that in the 1950–1969 period, respectively. There is a positive correlation between the annual maximum NDVI and annual runoff and sediment discharge. This correlation was reversed since the implementation of the GGP in 1999 and vegetation cover in the He-long area has increased, associated with the decrease in runoff and sediment discharge. Less precipitation has been an important fac-tor driving the decrease in runoff and sediment discharge during 1999–2007. However, restoration and improvement of the vegetation cover may also have played a significant role in accelerating the decrease in annual runoff and sediment discharge by enhancing evapotranspiration and alleviating soil erosion. 相似文献
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黄河中上游防护林工程现状及发展对策 总被引:3,自引:0,他引:3
通过对黄河中上游防护林工程建设取得显著成效和各地治黄典型经验的总结和分析 ,指出了工程建设所面临的问题 ,并据此提出了保证黄河中上游防护林工程建设顺利发展的 7条对策 相似文献
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在森林资源分类经营的背景下,由于商品林和生态林的经营目的不同,在长江中下游区域松毛虫危害松树对两类林分所产生的后遗效果相反。本文分析认为:松毛虫对于商品林会造成灾害,而对于生态林则有利于生态系统的发育成熟。 相似文献
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青海省互助土族自治县台子乡大菜子沟村,自20世纪50年代选择沙棘作为先锋树种造林,至今近50年,森林覆盖率达32.7%,有效地控制了当地的水土流失,改善了生态环境,促进了农牧业生产的发展,增加了群众收入,改善了群众生活。 相似文献
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黄土丘陵区沙棘优良品种引种试验研究 总被引:10,自引:0,他引:10
1993~2004年在黄土高原半干旱区的陕西吴旗,安塞县进行了沙棘优良品种引种试验研究。通过引种国内不同地理种源20余种优良沙棘类型,引进10余种俄罗斯优良沙棘品种,采用家系选择法,初步筛选出生态经济型5种沙棘类型,经济型3种类型。前者生长迅速、树冠好、根系发达、郁闭快、水土保持效益好,且果实较大(果径0.8~0.9cm,百果重22~31g),单株产量2~3.5kg,V-C含量较高,其生态、经济性状较当地野生沙棘为好。此种类型沙棘适于在黄土丘陵区大面积荒沟、荒坡种植。通过引种俄罗斯大果、无刺沙棘优良品种与本地野生中国沙棘对比分析看出,其适应性、抗性较中国沙棘差,经济性状较好。通过试验筛选出3种优良类型,果径为0.9~1.3cm,百果重46~52g,单株产量2~5kg,无刺或少刺。俄罗斯沙棘与中国沙棘杂交种,效果较好。此项研究为在半干旱黄土丘陵区大面积荒山、荒沟建造高产、优质沙棘林,高效、持续发展沙棘产业具重要意义。在引种试验中必须掌握好其关键技术,建立好采穗圃、种子园,并建立一定面积的集约经营高产、优质沙棘园及良种繁育基地,掌握水、肥等项抚育管理技术。 相似文献