【作者】 孟庆香；

【导师】 常庆瑞；

【作者基本信息】 西北农林科技大学 ， 土壤学， 2003， 硕士

【摘要】 当前，人口、资源、环境矛盾十分突出，土地生产潜力及人口承载量研究日益为人们所重视。陕北农牧交错带自然环境恶劣，生态系统脆弱，长期以来，粮食不能自给。随着人口不断增长，人地关系日趋紧张，食物生产同食物消费成为困扰区域经济发展的重大问题。因此，研究该区土地生产潜力及人口承载量，对于促进粮食生产、协调人地关系和社会经济持续发展均具有重要的战略意义。本项目在野外考察和资料收集的基础上，对陕北农牧交错带土地生产潜力及人口承载量进行了系统的分析研究，得到以下主要结论和成果： 1 采用逐步订正法估算作物生产潜力。陕北农牧交错带作物光合生产潜力、光温生产潜力、气候生产潜力和土壤生产潜力分别为22290kg／hm~2、14536kg／hm~2、5510kg／hm~2和1774kg／hm~2，降水和土壤肥力是作物生长的主要限制因子。7县区气候生产潜力从高到低排序为：府谷＞佳县＞靖边＞榆阳＞神木＞横山＞定边，土壤生产潜力排序为：定边＞神木＞府谷＞横山＞榆阳＞佳县＞靖边。提高土地生产潜力一方面要调控降水，加强基本农田建设，兴修水利，应用集流节水技术，发展灌溉农业；另一方面要改良土壤，培肥地力。 2 运用迈阿密模型对天然草地自然生产力进行估算。草地热量生产力远远大于水分生产力，根据李比希最小因子定律选择水分生产力作为天然草地的第一性生产力，全区天然草地自然生产力为7027kg／hm~2，7县区从高到低排序为：府谷＞神木＞佳县＞榆阳＞横山＞靖边＞定边。当前天然草地可食鲜草潜在产量2164kg／hm~2，仅为自然生产力的30.80％，还有很大的潜力可以挖掘。 3 耕地现实生产能力为707.51kg／hm~2，仅占土壤生产潜力的39.88％，气候生产潜力的12.84％，不到光温生产潜力的5％。人均粮食占有量为285kg／a，未达到温饱消费标准，粮食难以自给。1996年可承载牲畜213.01万只羊单位，实际年底存栏量254.73万只羊单位，超载19.59％。 4 采用一元非线性回归模型对耕地进行预测，2005年耕地面积下降到79.59万hm~2，2015年降为76.79万hm~2，2030年将降至72.57万hm~2，是现有耕地面积的88.0％。同期复种指数分别是1.06、1.08、1.10，并对作物种植结构进行优化调整。运用灰色关联法对人工要素投入与耕地产出进行分析预测，到2005、2015和2030年，耕地生产力分别为884kg／hm~2、1110kg／hm~2和1269kg／hm~2。以1996年为基础，估算2005、2015和2030年饲草载畜能力分别达到255.13、312.63和384.53万只羊单位，较现状提高19.78％、46.77％和80.52％。 5 该区生物生理性人口承载量1214.77万人，订正后的生物生理性人口承载量为913.99万人，理想人口承载量为621.17万人。由于短期内土地最大生产力无法达到，生物生理性人口承载量和理想人口承载量近期内难以实现。根据不同时段投入下土地生产能力和人口发展预测，从现在到2030年，区域人口一直处于严重超载状况。 6协调人地关系，提高区域人口承载力的主要对策是:实行计划生育，严格控制人口增长;大力发展教育，提高人口素质;强化科技意识，推广先进技术;增加投入，提高土地生产能力:提高植被覆盖度，控制土地荒漠化，改善生产环境。更多还原

【Abstract】 With population expanding, resources shortness, environmental deterioration and food deficiency, more and more eyes were fixed on land production potentiality and land carrying capacity. The agriculture and pasturage zone of Northern Shaanxi is an important area in China for its geography and environment, its food can not carry the population. Study on land production potentiality and land carry capacity has strategic significance for the zone. Based on field review and data collection, we study the land production potentiality and land carrying capacity in the zone. The main conclusions are as follows.1 The research estimates the cropland production potentiality by step correct method. It is surveyed that in this region the light production potentiality is 22290 kg/hm2, the thermal production potentiality is 14536 kg/hm2, the climate production potentiality is 5510 kg/hm2 and the soil production potentiality is 1774 kg/hm2, water and soil are limiting factors. The order of the climate production potentiality is: Fugu>Jiaxian>Jingbian>Yuyang>Shenmu> Hengshan>Dingbian, and the order soil production potentiality is: Dingbian>Shenmu>Fugu >Hengshan>Yuyang>Jiaxian>Jingbian. At the same time, this paper describes the guiding suggestions to improve the cropland production potentiality.2 The research calculates the grassland production potentiality as well as the cropland, which is according to the fact of the zone where agriculture and herd are both important. The paper calculates the crude grassland production potentiality by Miami Model, it is 7027 kg/hm2,the order of 7 counties is: Fugu>Shenmu>Jiaxian>Yuyang>Hengshan> Jingbian>Dingbian but the edible grass is 2164 kg/hm2, which is only 30.8% of production potentiality in 1996. There has great potential to exploit.3 The land actual production is 707.51 kg/hm2, which is just 39.88% of the soil production potentiality, 12.84% of the climate production potentiality, not enough 5% of the thermal production potentiality. Grain per capita in hand is just 285 kg/hm2 every year, it is lower than the lowest consumption standard of China and has a greater gap with the consumption standard in the world. The grassland actual production is low too. It can carry2130. thousand sheep but there are 2547 thousand sheep in 1996, the overloading rate is 19.59%..4 The paper estimates the land production potentiality dynamically and statically to make the result having more forecasting signification. In the DPS (data processing system), with non-linear regression analysis, we forecast the cropland will decline to 795.9 thousand hm2 in 2005, 767.9 thousand hm2 in 2015 and 725.7 thousand hm2 in 2030. With the gray relational grade method, the research calculates the production potentiality at different year and cost, we concludes 884 kg/hm2, 1110 kg/hm2 and 1269 kg/hm2 in 2005, 2015 and 2030. We forecasts the livestock carrying capacity is 2551 thousand sheep in 2005, 3126 thousand sheep in 2015 and 3845 thousand sheep in 2030. We draw the concluding that the livestock carrying capacity will increase 19.78%, 46.77% and 80.52% in 2005, 2015 and 2030.5 Energy statistical method is used to research land carrying capacity, which is according to the trend, convenient for comparing during different zone and substitute for different kinds of food. The land limited carrying capacity is 12148 thousand persons in the agriculture and pasturage zone of Northern Shaanxi, and the corrected land most carrying capacity is 9140 thousand persons, and the ideal carrying capacity is 6212 thousand persons. In possible cost, overloading is in all the counties.6 The research analyses the status and trend of human-land relationship in the zone. Countermeasures to control the relationship conclude: family planning to control population; consolidating education for population diathesis; intensifying realize to generalize science and technology; adding agriculture cost; more vegetation to control desertification.更多还原