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凉州区农业生态系统可持续性动态演化研究

Dynamical Evolution on Sustainability of the Liangzhou District Agro-ecosystem

【作者】 颉鹏

【导师】 蔺海明;

【作者基本信息】 甘肃农业大学 , 作物栽培学与耕作学, 2003, 硕士

【摘要】 可持续发展的定量评估是可持续发展研究的关键领域,其核心是确定人类生存是否处于生态承载力的范围之内。本文通过对甘肃省凉州区农业生态系统的可持续性,以大量统计资料和调查资料为基础,采用能学分析、生态足迹及环境资产负债等研究模型和分析方法,全面系统地研究了凉州区农业生态系统的能量运转规律、生态足迹及环境资产负债的动态变化,进一步提出凉州区农业可持续发展的战略。通过研究得出以下结论: 1.凉州区农业生态系统能量运转及演变规律表明该区农业生产出现以无机能投入为主的特点。农业生态系统投能水平逐年增加,2000年已达到102.85×1010J/hm2.a。但仍在投能适宜区间之内,为投能适宜区间上限的57.6%,表明凉州区农业生态系统仍具有增加投能的空间。无机投能和有机投能逐年上升,2000年较1949年增长了50.85倍,有机投能增加了80.54%,投能结构发生了根本性变化,由有机投能为主演变为以无机投能为主,转换拐点基本上出现在1970年。2000年产出能较1949年增加3.26倍,产投比由2.394下降到1.205,趋于合理。 2.凉州区生态足迹与生态承载力表现出阶段性发展趋势。1949年—1980年段呈稳中有升的发展态势;1980年—1985年段为快速增长阶段,且二者迅速上升至峰值,人均生态足迹为2.506hm2,人均生态承载力为2.614hm2;1985年—2000年段呈波动式下降趋势。生态盈余与生态赤字的拐点出现在1975年,且赤字呈负增长趋势,生态赤字的出现表明凉州区农业生态系统处于不可持续的状态。依据可持续性评价标准,凉州区从1949年—1970年段属于地方可持续性类型,20世纪70年代以后,基本上属于地方非可持续性类型。 3.凉州区环境资产呈阶段性发展趋势,1949年—1975年段为急速下降阶段,1975年以后为波动式增长阶段;环境负债自1949年以来,一直呈负增长趋势,2000年较1949年负增长了69.75倍;环境净资产自1949年以来呈下降趋势,2000年较1949年负增长了3.77倍,而且转换时期出现在1975年,生态净资产出现负值表明凉州区农业生态系统处于不可持续的状态。依据可持续性评价标准,凉州区农业生态系统从1949年—1970年段属于一级生态水平,20世纪70年代以后属于二级生态水平。 4.提出了凉州区农业可持续发展思路:实施生态工程,改善生态环境,调整农业产业结构,发展资源效益型、智能密集型的农业,在种植业内部逐步形成粮、经、饲三元结构,重点发展高产、优质、高效及名、优、特、稀农产品:在能量投入方面,应采用以有机能为主或有机-无机相结合的原则,加强农业生态系统物质和能量的循环,实现物质与能量的多级利用,提高利用效率;实施农业节水工程,开展农田水利建设,建立节水灌溉农业体系,推广滴灌和(微)喷灌技术,提高保灌率和水资源利用率;在退耕还林还草方面,宜林则林,宜牧则牧;控制人口增长,重视基础教育,积极推进经济增长方式的转变,提高经济增长的质量,走可持续发展的道路。

【Abstract】 Quantitative evaluation is a key field of the sustainable development and a judgment whether man’s activity has been in its ecological carrying capacity. Making a thorough study to find out development strategy of the Liangzhou district has an important scientific and practical significance. Based on many statistical and finding data, a systematic research has focused on the energy flow and its transformation, ecological footprint and environment asset and liability through applying such research modes and analyzing methods like energy analysis, ecological footprint and environment asset and liability etc. Based on the research, the conclusions drawn are as follows:1.Conclusions drawn on the basis of the study on energy characteristic and developing law of Liangzhou district agro-ecosystem have shown that the agricultural production in this area has the character with inorganic energy input. The energy input level has been gradually increasing annually and reached 112.85X1010 J/hm2.a in 2000, but it was just still within an appropriate range, only reached the maximum energy input value of 57.6%. This means, there are still spaces for energy input in this area. Meanwhile, the inorganic energy input was increased by 50.85 times compared with -that in 1955, while the organic energy input at the same period was increased by 80.54%. The structures of energy input also changed radically, from an organic energy input dependant pattern to an inorganic energy input dependant one. The period of transformation had come being in 1970.The ratio between the total amounts of energy input between inorganic and organic in 1949 was 1:12.94, and was 2.29:1 in 2000. The energy output capacity in 2000 wasincreased by 3.26 times compared with that in 1955.But the proportion between output and input at the same period decreased from 2.394 to 1.205.2. Research on the ecological footprint in Liangzhou district has shown that the ecological footprint and ecological carrying capacity had a trend of periodic increment. The ecological carrying capacity was on the remainder stage from 1949 to 1980, both the ecological carrying capacity and footprint were on a low growth stage at the same period. From 1980 to 1985, they both were on a rapid growth stage, which showed a relative balance for a short period. From 1985 to 2000, the ecological carrying capacity was on deficit stage, both the ecological carrying capacity and footprint assumed a decline tendency. The transformation period between ecological remainder and deficit was in 1975, and the deficits had negative increment with acceleration in recent years. These deficits have shown that the agricultural development in Liangzhou district has deviated far away from a sustainable one. Viewed the sustainable conception, agricultural development in Liangzhou district can be sustainable from 1949 to 1970 and can’t be sustainable since 1970.3.Study on environmental asset and liability in Liangzhou district has shown that the environmental assets have been reducing continually. Changed by stages into assumed a decreasing tendency during 1949 to 1975. Then it somewhat rose since 1975. The environmental liabilities also have been decreasing, and it was increased by -69.75 times in 2000 compared with that in 1949. The environmental net assets assumed a decline tendency from 1949 to 2000 and it was increased by -3.77 times in 2000 compared with that in 1949. The transformation period between the environmental assets and liabilities was 1975. These negative net assets have shownthat the agricultural development in this area has deviated far away from a sustainable one.The agricultural development in Liangzhou district can be in the first ecological level from 1949 to 1970 and be in the second ecological level since 1970.4. A general train of thought for the sustainable development of the Liangzhou district agro-ecosystem has been put forward: some ecological engineering should be implemented, ecological environment should be improved, agricultural and industrial structure s

  • 【分类号】S181
  • 【被引频次】2
  • 【下载频次】229
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