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1.
多功能性评价是土地多功能利用研究的重要问题。通过构建基于生产、生活、生态的土地多功能识别体系,采用全排列多边形综合图示指标法测度了1990年、2000年、2010年湖南省土地多功能状态及其变化。研究表明:(1)全排列多边形图示指标法可用于土地多功能性评价,模型系统整合了评价对象的多种因素,减少了主观因素的影响,提高了评价的客观性和科学性;(2)研究期间,湖南省土地总功能由1990年的0.10提高至2000年、2010年的0.22,0.40。重心由农业生产功能转变为经济生产功能、生活功能等,功能之间协调性逐步下降;(3)单项功能方面,除农业生产功能有所降低外,经济生产、交通保障、社会保障、就业支撑、居住家园以及生态功能均有不同程度提升。建议今后土地利用中应稳定和提高生态功能,提升土地的农业生产、就业支撑、社会保障等功能,并加强功能间的协调发展。 相似文献
2.
中国已经进入城市化发展的加速阶段,快速的城市化过程加大了对土地的高需求,土地集约利用直接影响到武汉城市圈土地利用和管理效果,关系到城市圈的城镇化进程。采用全排列多边形综合图示指标法对武汉城市圈2001—2010年间土地集约利用变化进行了量化评价。研究表明:(1) 全排列多边形图示指标法可用于土地集约利用的评价,该方法系统整合了评价对象的多种因素,并减少了主观因素的影响,使评价更为客观科学;(2) 单项指标显示,10 a间,武汉城市圈土地投入强度、土地利用强度、土地产出效益和土地环境质量均有明显提高;(3) 武汉城市圈土地集约利用综合指数总体呈增长态势,且前阶段的增长速度慢于后阶段,经济增长方式发生改变。因此,武汉城市圈在未来一段时间应把握住发展契机,通过增强土地利用的投资强度和产出绩效,不断提高土地集约利用水平;同时注重土地环境质量改善,优化城乡建设用地结构,提高土地的集约利用水平。 相似文献
3.
[目的]探究湖南省耕地多功能综合强度与协调度,为该省提高耕地多功能管理水平提供科学参考.[方法]采用全排列多边形图示法和系统聚类方法对2018年湖南省各县(区)的耕地多功能强度和协调度进行测算.[结果]①湖南省各县(区)耕地多功能综合强度由湘西北部向湘中部、湘东南部弱化,多功能协调度由湘西部到湘中部再到湘东部先增强后减... 相似文献
4.
从经济状态、环境状态、社会状态3个方面建立了水库生态安全评价指标体系,应用全排列多边形图示指标法构建评价模型,对福建省山仔水库2000-2003年生态安全状况进行了评价。结果表明:2000-2003年期间,山仔水库经济状态、环境状态、社会状态总体上呈上升趋势,但仍然处于较差水平;综合考虑经济状态指数、环境状态指数、社会状态指数后,山仔水库生态安全状况优劣顺序为:2002年〉2003年〉2001年〉2000年。评价结果较为客观地反映了该区域生态环境安全状况,对于生态安全薄弱区的生态环境保护、资源利用和可持续发展具有指导意义。 相似文献
5.
阐述了土壤肥力的概念,分析了土壤肥力评价的指标选取和方法选择,提出了科学合理的综合性评价指标体系和评价方法。 相似文献
6.
水土保持林作为保持水土、防止土壤侵蚀的特有林种,对于提高土壤肥力具有重要作用。常见的评价土壤肥力的指标有土壤酶活性、土壤有机质含量、土壤有机-无机复合体和微团聚体、土壤颗粒组成、土壤微生物数量以及土壤的其它理化性状等。通过分析不同水土保持林的土壤酶活性和土壤有机质含量。对其土壤肥力进行了评价。结果表明,有林地土壤肥力高于无林地;油松-阔叶树混交林土壤肥力比油松纯林更高;同一林分随着林龄的增长,土壤 相似文献
7.
水土保持林作为保持水土、防止土壤侵蚀的特有林种,对于提高土壤肥力具有重要作用.常见的评价土壤肥力的指标有土壤酶活性、土壤有机质含量、土壤有机-无机复合体和微团聚体、土壤颗粒组成、土壤微生物数量以及土壤的其它理化性状等.通过分析不同水土保持林的土壤酶活性和土壤有机质含量,对其土壤肥力进行了评价.结果表明,有林地土壤肥力高于无林地;油松-阔叶树混交林土壤肥力比油松纯林更高;同一林分随着林龄的增长,土壤肥力也在增加;各地类土壤的肥力水平均表现为表层最高,中层次之,下层最低. 相似文献
8.
碳排放的不断增加导致了全球变暖等诸多气候问题,土地是碳排放的载体,土地利用方式对碳排放量有着重要的影响。运用文献分析法查找有关土地适宜性评价的相关研究,将碳平衡引入土地适宜性评价中,建立了城市圈土地碳平衡适宜性评价指标体系。应用全排列多边形图示指标法,分别从碳源和碳汇两个角度对武汉城市圈各城市的土地适宜性进行了评价,研究发现,碳汇适宜性较高的城市有咸宁市、黄冈市和孝感市,碳源适宜性较高的城市有仙桃市、潜江市、天门市,通过图示可以直观地发现各城市的优势和不足。以土地利用结构和土地碳排放当量为依据估算各城市碳源碳汇总量,通过计算平衡因子、碳源碳汇比例等综合指标分析各城市土地碳平衡潜力,结果显示,各城市碳平衡潜力差异显著,工业较发达地区在碳平衡方面一般处于劣势。在城市圈发展中,区域整体的碳平衡更有利于实现城市圈的协同发展。 相似文献
9.
水稻土作为典型的水耕人为土,其土壤肥力是水稻优质高产的重要基础,肥力评价是稻田培肥和管理的重要内容之一。然而,稻田肥力评价指标和方法的选择存在较大不确定性。通过分析不同土壤肥力评价方法特点,土壤肥力指标的影响因素和变化特征,对我国水稻土肥力评价的现状进行了总结。在选择评价方法时应最大程度地减少人为的主观性,同时,如何将作物产量纳入土壤肥力综合评价值得进一步探讨。在对稻田土壤肥力进行综合评价时,土壤容重、总孔隙度、土壤团聚体和黏粒含量可作为土壤物理肥力指标的主要因子;土壤化学肥力指标随着施肥、耕作模式和稻作区域的差异应各有侧重;众多的土壤生物学指标中,微生物量碳氮、酶活性和微生物群落结构等需重点关注。下一步应制定一套针对不同稻作区典型施肥和耕作模式下比较完整和有代表性的评价指标体系,以及客观又简单实用的评价方法,为以水稻高产优质为目标的土壤培肥技术提供参考。 相似文献
10.
[目的]以河南省新乡市赵固二矿煤粮复合区为典型案例区,对该区土地利用多功能性进行研究,为其区域功能发展提供支撑。[方法]基于研究时序统计年鉴等基础数据,从"三生"功能(生产功能、生活功能、生态功能)角度择选出符合不同子功能的15个指标因子,构建出适用于煤粮复合区的评价指标体系。运用全排列多边形综合图示法对研究区2009—2015年间土地利用功能演变进行量化评价。[结果](1)全排列多边形综合图示法评价结果直观、准确、涉及面广且主观随意性低,适用于区域土地利用功能评价;(2)单项指标显示,2009—2015年间,各子功能的指标偏向侧重度均有所改变,但其主导障碍因子稳定不变;(3)7a间,研究区均以生产功能作为区域主导功能,受区域煤炭开采影响土地集约利用综合指数以2012年为分界点总体先增加后减少,变化速率为快—缓—快。[结论]煤炭开采活动对煤粮复合区土地功能利用有重要影响,区域土地"三生"功能变化及区域土地集约利用程度与区域煤炭事业的发展变化联系紧密。 相似文献
11.
通过大量样品分析和数据收集,研究了最近20年来东北典型黑土地区土壤肥力质量主要指标——pH、有机质、速效磷、速效钾和黏粒的变化情况,并在地理信息系统和地统计分析的辅助下,研究了该5项肥力指标以及综合肥力指数的时空变异规律。结果表明:20年中该地区土壤pH、有机质和速效钾平均含量明显降低,速效磷平均含量有较大增加;速效磷的变异系数变化最大,pH变化最小;20世纪80年代该地区土壤肥力综合指数以一、二级为主(80%以上),但21世纪初土壤肥力质量几乎被二、三级地所占据(98%以上)。该地区土壤肥力质量明显降低可能与长期以来重种轻养有关。 相似文献
12.
对26个20多年长期定位试验的褐土土壤肥力质量和产量变化进行了分析。结果表明,从1986年到2006年,褐土区土壤有机质含量由11.50 g/kg上升到15.75 g/kg; 全氮由0.73 g/kg上升到1.07 g/kg; 碱解氮含量由73.5 mg/kg 上升到94.6 mg/kg,20年增加了21.1 mg/kg; 有效磷含量1998~2006年增加幅度较大,由18.1 mg/kg上升到28.7 mg/kg,年增加1.3 mg/kg; 速效钾含量也随时间呈一定的增加趋势。总之,褐土肥力总体呈稳中有升的趋势。土壤有机质、全氮、碱解氮和有效磷含量的上升趋势较土壤速效钾明显,土壤酸碱度保持基本稳定,作物产量也呈现了一定上升趋势。 相似文献
13.
To ameliorate degraded red soils and restore their productivity, it is necessary to quantitatively assess the effects of different land uses on soil fertility. In this study, surface soil samples (0–20 cm) under different land uses were collected from an 18-year ameliorative experiment site of a eroded red soil in Lanxi county, Zhejiang province of southern China. The status of surface soil fertility was quantified with a ryegrass growth test in the greenhouse and by numerical analysis of twelve important fertility indexes. The soil fertility indexes were grouped into three major factors using a factor analysis, i.e., organic matter-nitrogen-structure, acidity and phosphate. By means of principal component analysis and cluster analysis of these fertility factors, the fertility of the eroded red soil as a function of land use patterns had the following decreased order: vegetable land>paddy field, cropping arable land and ryegrass land>tea garden>citrus garden>forestland>wasteland. The result suggested that organic matter, total N, available N, and water-stable aggregates were the main characteristics for fertility restoration of the eroded red soil. Soil fertility was most rapidly restored where the soil had been used as vegetable land, and least restored when left as wasteland. The results indicated that land use strongly affected the fertility restoration of eroded red soils because of its effect on the input of nutrients and energy, thus determining the speed and direction of soil fertility evolution. 相似文献
14.
针对目前黄淮海平原盐渍土改良区存在的土壤盐渍障碍问题,以该区域典型县域禹城市为研究对象,综合运用GIS和非参数地质统计学的指示克立格法,对县级和镇级两个采样尺度下0~20 cm耕层土壤盐分的空间变异性进行了分析,并给出了土壤盐分满足一定条件的概率分布图.结果表明,两个采样尺度下土壤盐分均不符合正态分布且都存在特异值,但... 相似文献
15.
The distribution and growing conditions of Cupressus chengiana forests along with the physical and chemical properties of soils in Northwest Sichuan were studied in 2002 to investigate the conditions and characteristics of soil fertility of C. chengiana and to compare and investigate differences of soil fertility for six C. chengiana populations and their relationships with vegetation, climate and disturbance. The results of the study at 0-20 cm soil depth showed that 1) significant differences (P〈0.05) existed among populations for soil bulk density, soil total porosity, capillary porosity, maximum water-holding capacity, capillary water-holding capacity and topsoil natural water content; 2) chemical characteristics of soil organic matter, total N, total P, alkali-hydrolyzable N, available P, available K and cation exchange capacity were significantly different among the populations; and 3) based on the significant effect of soil fertility factors on forest growth, soil physical and chemical characteristics could be selected as an integrated fertility index (IFI) for evaluation of different C. chengiana populations. Principal component and cluster analyses showed significant differences probably due to the difference of vegetation conditions, management measurements, human-induced disturbances and environmental factors. In order to protect the soil ecological functions in fragile ecological regions, C. chengiana could be used in programs enclosing the hill for natural afforestation, natural forest protection programs, and programs replacing agriculture with afforestation measures. 相似文献
16.
长期定位试验研究化肥与有机肥配施对砂姜黑土土壤肥力和作物产量的影响结果表明 ,长期施肥可提高土壤碱解氮、速效磷及有机质含量 ,不同肥料组合间差异较大 ,以有机肥与化肥配施处理效果最佳 (但同时必须重视K素的投入 ) ,土壤速效钾仅全部施用有机肥处理有所增加 ,单施N、P化肥处理下降最多 ,至 15年后下降2 5 .8%。长期未施肥处理 (对照 )碱解氮变化最大 ,较试验前下降 2 6 .5 % ,其他养分指标变化较小。有机肥与化肥配施处理产量前期不及单施化肥处理 ,中后期则反之。砂姜黑土基本生产力随种植时间延长而渐降 ,土壤对秋粮大豆或玉米的供肥能力高于小麦。 相似文献
17.
Structure is an important physical feature of the soil that is associated with water movement, the soil atmosphere, microorganism activity and nutrient uptake. A soil without any obvious organisation of its components is known as apedal and this state can have marked effects on several soil processes. Accurate maps of topsoil and subsoil structure are desirable for a wide range of models that aim to predict erosion, solute transport, or flow of water through the soil. Also such maps would be useful to precision farmers when deciding how to apply nutrients and pesticides in a site-specific way, and to target subsoiling and soil structure stabilization procedures. Typically, soil structure is inferred from bulk density or penetrometer resistance measurements and more recently from soil resistivity and conductivity surveys. To measure the former is both time-consuming and costly, whereas observations made by the latter methods can be made automatically and swiftly using a vehicle-mounted penetrometer or resistivity and conductivity sensors. The results of each of these methods, however, are affected by other soil properties, in particular moisture content at the time of sampling, texture, and the presence of stones. Traditional methods of observing soil structure identify the type of ped and its degree of development. Methods of ranking such observations from good to poor for different soil textures have been developed. Indicator variograms can be computed for each category or rank of structure and these can be summed to give the sum of indicator variograms (SIV). Observations of the topsoil and subsoil structure were made at four field sites where the soil had developed on different parent materials. The observations were ranked by four methods and indicator and the sum of indicator variograms were computed and modelled for each method of ranking. The individual indicators were then kriged with the parameters of the appropriate indicator variogram model to map the probability of encountering soil with the structure represented by that indicator. The model parameters of the SIVs for each ranking system were used with the data to krige the soil structure classes, and the results are compared with those for the individual indicators. The relations between maps of soil structure and selected wavebands from aerial photographs are examined as basis for planning surveys of soil structure. 相似文献
18.
试验研究有机、生物、化学肥料组合施肥技术及其对土壤肥力、籽实产量和经济效益的作用结果表明,连续2年试验各处理的土壤肥力、籽实产量和经济效益之间呈正相关,施用组合肥实较单施化肥土壤有机质增加0.01%-0.3%,籽实产量提高10%-16.9%,将增收932.6-1496.6元/hm^2。 相似文献
19.
2004年通过调查与第2次土壤普查(1982年)相对应地块的土壤性状,对太湖流域江苏省武进地区典型水稻土土壤肥力变化趋势及原因进行分析.结果表明:从1982年到2004年,该研究区主要的6类水稻土共198个取样点的有机质、全氮、速效磷、速效钾显著上升,而pH和CEC显著下降.各亚类水稻土,除小粉土和沙土肥力质量指数有较大幅度提高外,其他类型水稻土肥力质量指数增加不大.各亚类水稻土土壤肥力单因子质量指数变化趋向一致,即1982年各亚类土壤速效钾的单因子质量为最低,其中速效钾单质量指数最小的小粉土为1.48;2004年pH值的质量指数则为最小值,其中pH质量指数最小的白土仅为1.73;同时,各水稻土CEC单质量指数由第2次土壤普查时的2.91~3.0显著下降为2004年的2.14~2.93.因此土壤酸化并伴随盐基离子的淋失是限制研究区水稻土土壤肥力质量的关键因素. 相似文献
20.
China's northeastern Black Soil Region, one of the country's most important crop production areas, has been seriously affected by soil erosion. This study evaluated the effects of soil erosion on the long-term productivity of this region. We used a modified productivity index (MPI) model (MPI is a number between 0 and 1, with 1 indicating highest productivity) to assess the current effects of soil erosion on soil productivity, as well as to predict long-term change in productivity. Samples from 21 black soil profiles yielded varying MPI values, although most MPI values were indicative of moderate productivity. Organic matter content and available water capacity impact MPI values in the region, whereas soil clay content and pH were less important. Overall, organic matter content and available water capacity of soil profiles decreased consistently as depth of erosion increased. Modeling indicated that MPI in the region will decrease by 0.0052 for each centimeter of topsoil eroded; this rate represents 1% of the current average MPI for the study area. The model predicts a 9.6% productivity reduction over 100 years and a 48.3% reduction over 500 years. 相似文献
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