2018年土地科学研究重点进展评述及2019年展望 ——土地工程与信息技术分报告

研究目的：归纳分析2018年国内外土地工程与信息技术领域的研究进展，展望2019年国内研究趋势。研究方法：文献法。研究结果：2018年国内研究重点主要集中在耕地后备资源开发、生态整治、村庄整理、充填复垦技术、植物与钝化剂修复、无人机摄影测量与遥感技术在土地信息采集中的广泛应用及3S技术尤其是合成孔径雷达干涉测量技术在土地动态监测中的广泛应用；国外研究侧重于降低开发密度、土地整理有限领域选择、土地复垦碳排放问题、联合修复技术、土地信息处理方法的革新及多源遥感技术在土地动态监测中的应用。研究结论：2018年土地工程与信息技术，随着生态文明体制的改革、乡村振兴战略的提出及3S技术的迅猛发展，在土地生态整治、土地复垦技术、土地修复方法、动态监测技术等方面有所发展。2019年，将继续推进土地生态建设、进一步提升复垦土壤质量、优化复垦技术、改进污染土地修复方法，发展土地信息技术，在以解决生态环境问题和坚决打好污染防治攻坚战的前提下，推动生态文明迈上新台阶。     

基于行为—结果—反馈的粤西北山区“十二五”高标准农田建设绩效评价及低效因子诊断

[目的]弥补现有绩效观的不足,提出并解析了基于行为—结果—反馈的土地整治绩效评价内涵,开展粤西北山区"十二五"高标准农田建设绩效评价及低效因子诊断。[方法]从实施行为、效益结果、调查反馈3个方面建立指标体系,采用熵权改进的TOPSIS法和障碍度模型量化评估绩效水平并诊断低效因子。[结果]粤西北山区各县市在组织实施、综合效益和调查反馈方面各有不足,"十二五"高标准农田建设绩效水平总体有待进一步提高,绩效评价结果具有显著的区域差异,罗定市绩效值最高,绩效水平为良好;英德市、蕉岭县、南雄市、仁化县的绩效水平为中级;郁南县、龙川县、始兴县、云安县的绩效水平为低级;对于粤西北山区大多数县(市),实施行为作为首位低效因子,对高标准农田建设绩效的贡献度最小。[结论]基于行为—结果—反馈的绩效观,采用熵权改进的TOPSIS法和障碍度模型的绩效评价,能够客观衡量研究区高标准农田建设绩效水平。增加田间道路建设、提高土地流转面积、加强专项工作经费落实对于提高粤西北山区高标准农田建设水平具有普适性。     

连续梁墩梁固结研究——以二七长江大桥上跨铁路工程为例

结合武汉市二七长江大桥上跨铁路工程施工过程,采用模拟计算墩梁固结临时墩的受力,结合监控资料,得出其荷载的合理取值,并总结归纳墩梁固结的多种形式,分析优缺点,提出各种形式的适用范围。     

农田污染对粮食生产的影响研究——以四川为例

作为农业生产的根本,农田质量对于粮食生产而言至关重要,因此农田污染的相关防治已经成为我国农业可持续发展、农产品安全以及我国生态环境保护的重要措施。目前我国农田污染主要特征为农田污染物成分复杂,农田污染程度不断扩大。同时由于农田污染导致土壤肥力下降进而导致相关农作物的产量以及品质不断下降。文章以四川省为例,探究农田污染对粮食生产的影响,结果发现,目前四川省农田污染主要来源于农药化肥的不合理使用,水体以及土壤受工业废水污染严重,畜牧业废弃物污染等。农田污染导致可耕种土地面积不断减少,粮食生产受到严重影响。基于此,该文针对四川省农田污染现状提出农田污染综合立体防控策略,并在此基础上通过合理规划农业生产,减少农药化肥使用量,提高生物防治在病虫害防治当中的比例等措施减少农田污染对粮食生产的影响,以期为我国农田保护以及粮食生产提供一定的理论以及政策依据。     

The influence of risk preferences,knowledge, land consolidation,and landscape diversification on pesticide use

Researchers have spent substantial effort to identify factors influencing pesticide use intensity. However, few studies have compared the relative importance of these factors. This study examines four categories of factors that potentially influence farmers’ pesticide use decisions by evaluating incentivized experiment data, farm survey data, and remote sensing data in China. Our results suggest that land diversification has the largest effect on farmers’ pesticide use. Compared with the most rice-intensive landscape type, less rice-intensive systems cause farmers to spray less on middle rice. Heavy pesticide use intensity is associated with land fragmentation as small-scale farms still dominate crop production. Farmers’ integrated pest management knowledge has significant effects on pesticide use. We also find that loss and ambiguity preferences, rather than risk preferences, are more likely to affect pesticide use intensity.     

铁离子、亚铁离子变化对工业锅炉酸洗的影响

介绍工业锅炉酸洗中铁离子的来源,并以实例说明酸洗中应强化对铁离子、亚铁离子(Fe3+、Fe2+)的化学监测,使锅炉酸洗安全进行,及终点的判断。     

Co-ordination of land exploitation,exploitable farmland reserves and national planning in China

Land exploitation, as an important strategy to mitigate farmland loss and stabilize grain production, has been adopted to compensate farmland loss due to rapid urbanization in China. Bounded by the limited capacity and obvious spatial variations of national farmland reserves, it is essential to arrange land exploitation activities timely and reasonably. In this study, we propose an indicator for the status of regional land exploitation, the Exploitation Degree, to facilitate an overview of land exploitation programs in China at both provincial and prefectural levels based on project data from 2006 to 2012. To further our understanding of the regional features of land exploitation activities, we employ the Lasso model to identify and quantitatively assess influencing factors on land exploitation. Our study shows that: (1) contemporary land exploitation practices in China are significantly inconsistent across exploitable farmland reserves. Some areas are greatly over-exploited and such irrational land exploitation has been persistent; (2) related national land plans designed to guide land exploitation efforts centered on resource-rich regions and critical areas do not function as intended. Therefore, we suggest that China⿿s land exploitation policy shall be improved by reconsidering the orientation of land exploitation policy, coordinating land exploitation activities with productivity improvements and eco-system protection, and enhancing the power and scope of the plans in controlling and guiding land resource management.     

Land consolidation,customary lands,and Ghana's Northern Savannah Ecological Zone: An evaluation of the possibilities and pitfalls

Land fragmentation has been identified to greatly undermine crop production in many countries. In the case of Ghana’s customary tenure system, household farmlands are relatively small and are highly fragmented. Recent agricultural drives, however, have focused on farm level interventions that are ad hoc with short-term benefits. A sustainable long-term application of land consolidation which reorganises farmlands may improve yields, reduce the cost of production and improve the incomes of farmers. The successful implementation of land consolidation depends greatly on the suitability of local conditions with respect to land tenure and land use. However, in Ghana’s customary lands, the alignment between the requirements for land consolidation and existing conditions remains unexplored. This study investigated the feasibility of land consolidation within the customary tenure by juxtaposing the local conditions of the study areas with the baseline conditions for land consolidation outlined in literature. Using both qualitative and spatial data, the study revealed some traits of convergence and divergence with respect to the baseline conditions in the study areas. For example, conditions such as the existence of land fragmentation, suitable topography and soil distribution were fully met. Conditions such as the existence of a land bank, technical expertise, and infrastructure and supportive legal frameworks were partially met. The remaining conditions such as the willingness to participate, availability of a land information system and favorable land ownership structure were non-existent. The circumstances surrounding these unmet conditions are deeply embedded in customs and traditions that hardly yield to change. Since these conditions are fundamental for land consolidation, their absence negates the feasibility of land consolidation under the current tenure system of the study areas.     

耕地质量影响因素区域差异分析及提升途径研究——以河南省新郑市为例

研究目的:分析研究影响耕地质量的主要障碍因素及其区域差异,明确不同区域耕地质量提升的主要途径和重点建设内容,以提高耕地质量提升工程建设的针对性和实效性。研究方法:相关分析法,主成分分析法,聚类分析法。研究结果:(1)土壤质地、有机质、全氮、速效磷、速效钾、灌溉率是影响耕地质量的主要因素,与粮食单产间均呈线性正相关关系,影响因素相互间也有影响,存在着显著的相关关系;(2)单产影响因素的重要性存在明显差异,其重要性序次为:灌溉率、速效磷、全氮、有机质、速效钾、土壤质地,重要性系数分别依次为0.188、0.179、0.173、0.167、0.156、0.136;(3)新郑市的耕地可划分为3种类型的整治区,不同类型区的耕地质量及其影响因素差异明显,丘岗地区的耕地质量最差,是农田整治的重点区,主要障碍因素是灌溉率低、土壤肥力差。研究结论:新郑市不同区域耕地质量提升的主要途径不同,丘岗地区和砂土平原区主要是提高农田灌溉率和培肥土壤,山前平原区主要是提高土壤磷肥肥力。     

旅游业上市公司多元化经营能够降低公司风险吗？——基于2004—2012年A股上市公司数据的实证研究

我国的旅游业上市公司普遍存在进入房地产业、高新技术产业等行业的多元化经营现象。国内外学者对多元化经营与公司风险之间的关系展开了一系列的研究,但是没有得出一致的结论。截至目前,对旅游类企业多元化经营能否降低公司风险的研究仍较为欠缺。因此,文章以2004—2012年国内23家A股旅游业上市公司1的184个截面数据为样本,利用多元回归分析法检验了旅游业上市公司多元化经营对其公司风险的影响。旅游行业自身的行业特征及其多元化特点使得针对旅游业上市公司多元化经营行为的分行业研究产生了与以往整体层面的研究截然不同的结论：旅游业上市公司多元化经营能够降低公司的财务风险,但无法降低公司的经营风险。进一步对多元化类型进行区分后发现：旅游业上市公司相关多元化水平的提升可以显著地降低公司的财务风险,但无法显著地降低公司的经营风险;而非相关多元化水平的提升无法显著地降低公司的财务风险与经营风险。基于上述研究成果,文章从促进融资体系多元化、完善主业发挥自身优势、谨慎选择多元化行业3个角度对旅游业上市公司的多元化发展提出了建议。