【作者】 赵小勇；

【导师】 田军仓；

【作者基本信息】 宁夏大学 ， 水利水电工程， 2015， 博士

【摘要】 生产潜力作为土地最基本的功能,受气候、土壤、植物自身等多因子影响,关系到一个区域的社会经济发展方向,是区域开发和生态环境建设的重要基础条件,因此一直是农学、土壤、地理等多学科的研究热点。宁夏压砂地位于宁夏中部干旱带,多年平均降雨量200～400mm左右,压砂地分布在沙坡头区、中宁县、海原县部分区域。目前建成中卫环香山压砂瓜产业带,面积约达6.67万ha,逐步建设为中国压砂瓜生产基地。因地处宁夏中部干旱地,降水资源条件对产量影响非常大。水分不足是旱地农业发展的主要限制因素,如何有效地利用有限降水在干旱地区尤为重要。因此,对于压砂地这一特殊种植模式来讲,研究压砂地生产潜力问题,挖掘旱地自然降水生产潜力,提高自然降水利用效率,解决当地农业生产问题具有非常重要的意义。本文基于作物机理经验模型研究,通过对国内外大量文献研究,运用衰减法原理,选取压砂分布的一区两县,先后从理论分析、试验研究、运用GIS技术方法细化到乡镇,由于资料缺失原因,从中选取11个乡镇对宁夏压砂地生产潜力问题展开研究。理论分析是开展工作的基础。依据三个地区的48a气象数据,基于衰减法原理,逐次对光合潜力、光温潜力、降水生产潜力(气候生产潜力)、土地生产潜力进行系数订正,其中降水生产潜力按不同年份进行划分,同时考虑砂地休闲期降水保墒作用订正水分系数,以便掌握生产潜力的阈值,土地潜力则对土壤有效系数的9个影响因素进行综合订正。结果表明,自然降水还有一定开发潜力;通过分析得出影响压砂地生产潜力的关键因素依次为水分、土壤、温度,其相对影响系数排序为:水分(2.91)>土壤(0.77)>温度(0.46)。试验研究依据多年降雨量数据,运用降水频率分析方法,划分为干旱年、平水年、丰水年,并结合压砂年限分为新、老、中砂地,按照三个降水水平分别在课题试验区实施田间研究,得出了降水条件是干旱区影响产量的第一因素一般性结论。研究还总结出压砂年限久,产量衰减的规律;另外还总结出在不同降水条件下,新砂地可开发的生产潜力分别为13.1%、21.8%和43.1%;中砂地为30.7%、35.5%和44.6%;老砂地为50.6%、59.1%和66%,计算结果表明压砂地尚待开发的生产潜力较大,并提出老砂地改良仍是一大难题,应对老压砂地实施科学改良措施。试验结果表明,试验数据基本符合理论分析结论。为解决各乡镇无气象实测数据的问题,依据地域垂直分布分异规律,运用GIS空间内插法,模拟各乡镇太阳辐射、温度、降水量、蒸发量等关键因素取值,依据理论分析部分采用的衰减法原理过程,对压砂地区11个乡镇进行潜力估算,得出从空间上将压砂区域划分为三个潜力值区,呈现由南向北逐步递增的趋势;影响因素影响程度依次为水分、土壤、温度;通过空间GIS技术方法对农业产业布局具有一定参考价值。本文是对压砂地生产潜力的尝试研究,还有许多问题需要进一步细化,提高预测可靠程度。更多还原

【Abstract】 Land potential productivity is the basic function of land,affected by climate,soil,plants and other factors,related to the social and economic development of a region,is an important foundation for development and ecological environment construction area,so it is always research hotspots in agronomy,soil,geograpHy and other subjects.Gravel-mulched land located in the arid area in the middle of Ningxia,the average annual rainfall has about 200-400mm,gravel-mulched land area includes Shapotou District,Zhongning County,Haiyuan County.Gravel-mulched land watermelon zone is covering an area of about 66700 ha,gradually building to Chinese watermelon base.Located in the central arid,precipitation resources shortage is the main limiting factor for the development of dryland agriculture,how to effectively use the limited rainfall is especially important in arid area.For this special gravel-mulched planting pattern,studing potential productivity problems,mining potential precipitation productivity of dryland,improving the use efficiency of natural rainfall are very important to solve the problems of local agricultural productivity.This paper studies on crop mechanism model based on a lot of domestic and foreign literature researches,using the attenuation method principle,select gravel-mulched land areas in three counties,according to the theoretical analysis,experimental research,using the GIS method to different area.Due to lack of data,11 villages and towns of Ningxia gravel-mulched land are selected as objects to study potential productivity.The theoretical analysis is the basis of the work.On the basis of 48a meteorological data in the three areas,used the principle of attenuation method,calculated pHotosynthetic potential,light and temperature potential,rainfall potential productivity(climate production potential of land production potential)and corrected coefficient.Potential productivity of rainfall in different years were divided,considering effecttion of the sand leisure time precipitation and soil conservation moisture and correcting coefficient of moisture to know potential productivity,a comprehensive revision of land potential of the soil effective coefficient of 9 factors.The results show that,the natural precipitation has certain development potential;through the analysis of the main factors affecting the gravel-mulched land potential productivity in water,soil,temperature,the relative influence coefficient order:water(2.91)>soil(0.77)>temperature(0.46).Experimental research on rainfall data many years,use the analysis method of rainfall frequency,divided into dry,flat water years,wet years,combined with age limit of the gravel-mulched land is divided into three types.According to the three rainfall levels respectively in the test area of land,research results show that the rainfall is the first factor yield in arid area.The study also summarizes the gravel-mulched land years is longer,production will be declined faster;also summarized in different rainfall conditions,the new land can be developed potential is respectively 13.1%,21.8%and 43.1%;middle-year sand in 30.7%,35.5%and 44.6%;old sand was 50.6%,59.1%and 66%,the calculated results show that the sand has production potential to be improved,and put forward the improvement of old sand is still a big problem,deal with the old gravel-mulched field implementation of scientific improvement measures.Experimental results show that the theory analysis conclusion is consistent with experimental data.In order to solve the problem of no actual meteorological data for different towns,according to different vertical distribution law of regional division,using GIS spatial interpolation method,simulation of the township of solar radiation,temperature,precipitation,evaporation and other key factors,estimating potential productivity of 11 villages and towns sand area based on the theoretical analysis of the attenuation law principle part.Gravel-mulched land is divided into three potential value area from the space,presented from south to north gradually increasing trend;influences factors order is soil moisture,temperature;results has a certain reference value for agricultural industry layout through the method of spatial GIS technology.This paper is an attempt to study the gravel-mulched land potential productivity,there are many problems to be researched,and improve the prediction reliability in the future.更多还原