【作者】 苗洁；

【导师】 贺立源；

【作者基本信息】 华中农业大学 ， 资源环境信息工程， 2007， 硕士

【摘要】 土地是不可再生资源，采用先进的技术手段，科学管理、可持续利用土地资源一直是各国政府和相关研究者关注的热点问题。耕地是土地中初级生产的最重要资源，耕地地力的好坏直接影响到农业生产的发展。随着我国改革开放深入，耕地面积与质量变化对粮食安全构成了严峻挑战，受到党和政府以及研究者的日益关注。本研究于2005年采用GIS技术对武汉市汉南区耕地土壤主要农化性状进行了调查，并与1980年的第二次土壤普查的结果进行比较和分析，对汉南区耕地土壤有效养分的变迁进行了总体评价，为合理施肥，保护耕地，提高粮食产量，确保粮食安全提供了科学依据。主要的研究结果有：1．查清了耕地质量现状研究采集了武汉市汉南区301个耕地土壤样品，通过对采样点土壤属性分析与评价，查清了该区土壤有效养分现状。研究发现，该区大部分耕地土壤呈中性偏碱，pH平均值7.3，其中处于7.5～8.0区间的微碱性土壤占调查总面积的46.8％，pH值在7.0～7.5之间的中性土壤占总面积的43.6％。速效钾介于80～120 mg／kg之间，占总调查面积的61.3％；有36.0％的耕地速效钾大于120 mg／kg；只有2.7％的耕地速效钾小于80 mg／kg；有效磷水平总体较低，80.6％的耕地有效磷含量小于10.0mg／kg，其中有14.0％低于5.0mg／kg；介于10.0～20.0mg／kg之间耕地占调查面积的18.5％；只有少量耕地有效磷大于20mg／kg。汉南区耕地土壤有机质总体水平中等偏上，平均值为22.56 g／kg。其中88.2％的耕地有机质含量在15 g／kg以上，其中大于20 g／kg，占调查面积的44.9％，只有11.8％的耕地有机质含量在10～15 g／kg之间。现状反映，该区耕地土壤总体上磷供应不足，地块之间磷含量差异大；钾水平中等偏高，地块之间变异较小；有机质含量比较丰富，地块之间差异也较小；大部分土壤仍然呈微碱性，少量呈强碱性。2．分析了变化趋势研究结果表明，汉南区土壤pH总体变化不大，但是呈现两头向中间发展的趋势，25年前土壤主要pH介于6.7～8.0之间，平均值为7.4；目前pH介于6.6～8.0之间，平均值为7.3。经过25年的耕作，汉南区土壤pH值介于7.0～7.5的面积增加了8个百分点，pH值介于6.5～7.0的面积减少2.4个百分点，而pH值大于7.5的土壤降低5.6个百分点。土壤速效钾显著降低，25年前土壤速效钾平均值为146.03mg／kg；现在平均值为108.08 mg／kg，平均下降近40 mg／kg，下降幅度达到27.4％。土壤有效磷略有上升，25年前汉南区土壤有效磷平均含量为7.37 mg／kg，现在土壤有效磷平均值为8.62 mg／kg，大部分土壤仍然缺磷。通过25年前后耕地土壤养分的历史变迁可以推测，汉南区钾肥投入相对不足，原本丰富的土壤钾素正大量被消耗，应引起注意；磷素匮乏和土壤pH值偏高一直是限制该区农业发展的重要障碍因子。要改善土壤磷营养状况，除了增施磷肥之外，必须同时改良碱性土壤。3．提出了推荐施肥原则通过对汉南区耕地土壤现状和25年间的变化趋势分析得出，汉南区耕地土壤有机质总体水平可观，适当补充有机肥，合理利用现有的有机肥资源；汉南区多数土壤属石灰性潮土，因此最好选用酸性肥料；普遍增加磷肥的用量，选择酸性较强的过磷酸钙或重过磷酸钙品种；汉南区多数土壤钾素水平已从25年前的丰富水平下降到目前的中等水平，部分甚至呈现潜在性缺乏状态。因此对这些耕地要适当补充施用钾肥，尤其要重视对棉、麻以及经济作物钾素的补充。该地区砂质土壤较多，DH值偏高，这些土壤的保肥供肥能力较差，容易导致多种元素的固定和损失，逐步推广磷含量较高的复混肥。因此，汉南区在今后几年内要继续补充有机肥，稳施氮肥，重施磷肥，适施钾肥，补施中、微量元素，在肥料品种中尽量选用酸性肥料，并配合其它措施改良碱性土壤。4．建立了空间数据库数字化了汉南区的土壤图和土地利用现状图，作为空间数据库的基础图件，对汉南区总的土壤分布和利用现状有了整体认识。研究结果通过10余幅专题地图展示，让结果更加直观。研究还建立了该区的耕地资源和有效养分空间数据库。为以后的进一步研究和应用奠定了基础。更多还原

【Abstract】 The land is the non-renewable resources, uses the advanced technical method and scientific management, sustainable using the land resource always is the hot topic which the various countries’ government and the correlation researcher pays attention. The farming is in the land the primary production most important resources, the farming soil fertility quality directly affects the agricultural production development. With our country reform and open policy thoroughly, the cultivated area and the mass variation safely constituted the stern challenge to the grain, receives the party and the government as well as researcher’s daily attention.This research used the GIS technology in 2005 the area farming soil main agriculture character to carry on the investigation to Hannan of Wuhan, and carried on the comparison and the analysis with 1980 second soil general survey result, area farming soil available nutrient vicissitude has carried on the overall appraisal to Hannan. In order to apply fertilizer rationally, protects the farming,enhances the grain yield, guarantees the grain security, produced thegreen product to provide the scientific basis. The main findings include:1 Investigated thoroughly the farming quality present situationThe research has gathered Hannan 301cultivated land soils sample, through to the sampling soil attributeanalysis and the appraisal, investigated thoroughly this area soil available nutrient present situation. The research discovered that, this area majority of farming soil assumes the neutral leaning alkali, The pH mean value 7.3, in which is in 7.5～8.0 sectors the alkalescency soil to account for the investigation total area 46.8%,the pH value accounts for the total area between the 7.0～7.5 neutral soil 43.6%. The available K is situated between 80～120 mg/kg,occupies 61.3% of total investigation area; Some 36.0% farming available K is bigger than 120 mg/kg;Some 2.7% fanning available K is only smaller than 80 mg/kg; The available P horizontal overall is lower, 80.6% cultivated land available P content is smaller than 10.0 mg/kg, including 14.0% to be lower than 5.0 mg/kg; between 10.0～20.0 mg/kg cultivated land occupies the investigation area 18.5%; Only has the few cultivated land available P to be bigger than 20 mg/kg.Farming soil organic matter aggregate level moderate to superior, the mean value is 22.56 g/kg. 88.2% farming organic matter content above 15 g/kg,in which is bigger than 20 g/kg, occupies the investigation area 44.9%, only some 11.8% farming organic matter content between 10～15 g/kg. Present situation reflection, in the area overall the P insufficient supply, Lacks the P the land parcel to be more, moreover between the different land parcel the P content difference is big. The K level medium is high, majority of land parcels K content richer, between the land parcel the variation is smaller. Organic matter content considerable, between the land parcel the difference is also smaller. The majority of soils still assumed the alkalescency, few assumed the alkalinity.2 Analysis of the trendThe findings indicated that, the area of Hannan soil pH overall change is not big, but presents two to the middle development tendency, 25 years ago soil main pH is situated between 6.7～8.0, the mean value is 7.4; At present pH is situated between 6.6～8.0,the mean value is 7.3. After 25 years cultivation, the area of Hannan soil pH value has situated between 7.0～7.5 the area to increase 8 percentage points,the pH value has been situated between 6.5～7.0 the area to reduce 2.4percentage points, but the pH value was bigger than 7.5 soils toreduce 5.6 percentage points. The soil available K remarkably reduces, 25 years ago the soil available K mean value is 146.03 mg/kg; Now the mean value is 108.08 mg/kg, equally drops nearly 40 mg/kg, the drop scope achieves 27.4%. The soil available P slightly has the rise, 25 years ago the area of Hannan soil available P average contentis 7.37 mg/kg, now the soil available P mean value is 8.62mg/kg, the majority of soils still lacked the phosphorus. It is extrapolation that farmland soil nutrient change through 25 years around, K fertilizer investment relative insufficiency, originally the rich soil K element massively is consumed,should bring to the attention; The P element deficient and the soil pH value is high always is limits this area agricultural development the important barrier factor. Must improve the soil P nutrition condition, besides increases executes the P fertilizer, must simultaneously improve the alkali soil.3 The principle of fertilizer recommendationsThrough obtains to the Hannan farming soil present situation and 25 years change trend analysis, the Hanana farming soil organic matter aggregate level considerable, add organic fertilizer Appropriately, use of the existing resources of organic fertilizer Reasonably; The wuhan most soils are the calcareous moisture soil, therefore best selects the acidic fertilizer; General increase in the amount of P fertilize, choice acidity stronger calcium superphosphate or double superphosphate variety; The Hannan most soils K element level dropped from 25 years agorich level to the present medium level, partially even presents the latent deficient condition. Therefore to these cultivated land must suitably supplement the K fertilizer, especially must take the cotton, the hemp as well as the industrial crop K element supplement.Sandy soils in the region more, pH value high, these soils preserve and supply fertility for fatability worse, is easy to cause the many kinds of elements fixed and the loss, gradually promote higher levels of phosphorus fertilizer. Therefore, Hannan will have to continue in next several year to add organic fertilizer, steadily will execute the N fertilizer, again will execute the P fertilizer, suitably will execute the K fertilizer, will make up middle element and trace element, will select the acidic fertilizer as far as possible in the fertilizer variety, and will coordinate other measure improvement alkali soils.4 Established a spatial databaseIt has Digitized the soil map and the present land-use map of Hannan as a spatial database of maps,also has took the whole understanding of soil distribution and using the present situation of Hannan.The findings demonstrated through 10 special maps show, let theresult be more direct-viewing. The research has also established this area farming resources and available nutrient the spatial database. Have laid the foundation for the later further research and the application.更多还原