Integrated use of GIS, remote sensing and multi-criteria decision analysis to assess ecological land suitability in multi-functional forestry

The Zagros forests are a treasure of valuable oak forests, but they have been severely degraded from long-term misuse. Geographic information systems （GIS） and multi-criteria decision analysis （MCDA） have been increasingly used to improve the management of vulnerable ecosystems to prevent further degradation and increase the sustainability of land use. This study presents a methodology to assess land suitability using remote sensing （RS） to obtain wall-to-wall data for the calculations, GIS to analyze the data, and MCDA to rank alternative land uses. The criteria and subcriteria affecting the suitability of land for different uses were identified and weighted using an analytic hierarchy process. Variables used as subcriteria were assessed using satellite data and other sources of information such as existing maps and field surveys. Numerical values for the subcriteria were classified, and each class was given a priority rating according to expert judgments. Based on the ratings and weights of the subcriteria, a priority map was created for each land use using the weighted linear combination method. The priority maps for different land uses were overlaid to obtain a preliminary land use map, which often indicated several simultaneous land uses for the same location. The preliminary map was further edited by removing unrealistic, mutually exclusive land-use combinations. The study tested and demonstrated the potential of integrating RS, G1S and MCDA techniques for solving complicated land allocation problems in forested regions using a scientifically sound and practical approach for efficient and sustainable allocation of forestland for different uses.

Review on simulation of land-surface processes on the Tibetan Plateau

The Tibetan Plateau(TP) has powerful dynamics and thermal effects, which makes the interaction between its land and atmosphere significantly affect climate and environment in the regional or global area. By retrospecting the latest research progress in the simulation of land-surface processes(LSPs) over the past 20 years, this study discusses both the simulation ability of land-surface models(LSMs) and the modification of parameterization schemes from two perspectives, the models' applicability and improved parameterization schemes. Our review suggests that different LSMs can well capture the spatiotemporal variations of the physical quantities of LSPs; but none of them can be fully applied to the plateau, meaning that all need to be revised according to the characteristics specific to the TP. Avoiding the unstable iterative computation and determining the freeze-thaw critical temperature according to the thermodynamic equilibrium equation, the unreasonable freeze-thaw parameterization scheme can be improved. Due to the complex underlying surface of the TP, no parameterization scheme of roughness length can well simulate the various characteristics of the turbulent flux over the TP at different temporal scales. The uniform soil thermodynamic and hydraulic parameterization scheme is unreasonable when it is applied to the plateau, as a result of the strong soil heterogeneity. There is little research on the snow-cover process so far,and the improved scheme has no advantage over the original one due to the lack of some related physical processes. The constant interaction among subprocesses of LSPs makes the improvement of a multiparameterization scheme yield better simulation results. According to the review of existing research, adding high-quality observation stations, developing a parameterization scheme suitable for the special LSPs of the TP, and adjusting the model structures can be helpful to the simulation of LSPs on the TP.

Study of Swine Leukocyte Antigen Class I-3 (SLA-3) Gene for Inbreeding Wuzhishan Pig

To elucidate the structure of SLA-3 alleles on inbred line of Wuzhishan pig （WZSP） population, we examined the partial exon 1, completed exon 2, and partial exon 3 of SLA-3 loci using the reverse transcription-polymerase chain reaction （RT- PCR） and the sequencing-based method in 32 WZSPs. According to pedigree and amplification results, PCR products of 8 WZSPs were selected to clone and sequence. Nine different nucleotide sequences were obtained. After comparing the DNA and protein sequences of the WZSPs SLA-3 alleles with the published GenBank SLA sequences, it was found that the SLA-3 alleles in WZSPs were all novel, but there were very few variations among them. Comparision of SLA-3 and HLA-A protein sequences indicated that there was more sequence homology. Meanwhile, the construction of a phylogenetic tree using the nucleotide sequences of 23 SLA-3 alleles and 1 HLA-A allele represented that the WZSP population owns its unique genetics resource. In this study, the alleles of SLA-3 on WZSP group were successfully detected and analyzed, which provided the firm basis on the genotype of SLA-3 for breeding specific haplotypes WZSPs.

Spatial-temporal variation of the land surface temperature field and present-day tectonic activity

This study attempts to acquire information on tectonic activity in western China from land surface temperature （LST） field data. On the basis of the established relationship between heat and strain, we analyzed the LSTdistribution in western China using the satellite data product MODIS/Terra. Our results show that： 1. There are departures from annual changes of LSTin some areas, and that these changes are associated with the activity of some active tectonic zones. 2. When annual-change background values caused by climate factors are removed, the long-period component （LSTLow） of temperature residual （AT） of the LSTis able to serve as an indicator for tectonic activity. We have found that a major earthquake can produce different effects on the/ST fields of surrounding areas. These effects are characterized by both rises and drops in temperature. For example, there was a noteworthy temperature decline associated with the Sumatran M9 earthquake of 2004 in the Bayan Har-Songpan block of central Tibetan Plateau. 3. On the other hand, the LST field of a single area may respond differently to major shocks occurring in different areas in the regions surrounding China. For instance, the Kun- lun M 8.1 event made the LSTon the Longmen Mountains fault zone increase, whereas the Zaisan Lake M 7.9 quake of 2003, and the Sumatran M 9 event of 2004, caused decreases in the same area＇s LST. 4. The variations of land surface temperature （LST） over time are different in different tectonic areas. These phenomena may provide clues for the study of tectonic deformation processes. On the basis of these phenomena, we use a combi- nation of temperature data obtained at varied depths, regional seismicity and strain results obtained with GPS measurements, to test the information related to tectonic activity derived from variations of the LST field, and discuss its implications to the creation of models of regional tectonic deformation.

基于GIS的华北-辽南土地潜力区土地适宜性评价

以华北-辽南土地潜力区为案例区,研究了GIS技术支持下基于多要素空间数据进行土地适宜性评价的方法与技术,评价对象包括土地限制因子、土地限制型、土地质量等和土地适宜类。根据研究区的自然地理和土地资源系统特征,选取气候、地形、灌排水、土壤和植被等五大类10个指标为评价因子;应用基于栅格数据模型的空间分析技术在1km2尺度建立评价因子基础数据库,并将评价原则用地图代数语言加以表达,形成了“要素数据”、“原则标准”与“分析技术”相结合的、逐级递进的评价技术流程。案例区实证研究表明:评价方法与技术切实可行,高质量的基础数据、合理的评价方法和有效的分析技术共同保证了评价过程的准确与高效;案例区的土地限制因子以土壤质地、水文与排水条件、坡度和灌溉条件为主,而土地适宜类则以宜农类、宜林牧类和宜农林牧类为主。

美国赠地院校迈向世界一流农业大学的路径分析——基于2011-ARWU数据

由农业教育起家的美国赠地院校,在政治、经济和社会等多重矛盾的相互妥协中产生,经历了艰难困顿的初创时期,在适应与创新的相互作用中成长,其发展路径有注重公益性社会服务、关注教育民主、均衡与卓越相协调的学科布局、"有限自主与充分自治相结合"的管理架构以及科学统计与分析支持下的战略规划等特点,对中国高校在办学理念、学科建设、机制创新和制度完善等方面有较好的借鉴意义。

基于MSVM-CA模型的区域土地利用演变模拟

研究目的:探索一种基于多类支持向量机自动获取地理元胞自动机非线性转换规则的方法(MSVM-CA),并将其用来模拟复杂的土地利用动态演化。研究方法:以长江口北岸启东市2002—2007年的土地利用演变模拟为例,采用1-A-1方法在每两类样本数据间训练一个分类器,将模拟土地利用变化的主要特征变量映射到Hilbert空间,通过多类支持向量机建立最优分割超平面,运用决策函数计算元胞到最优分割超平面的距离,并转换为元胞土地利用类型的转换概率。然后利用蒙特卡罗方法,确定元胞的转化状态,循环完成土地利用演变模拟,最后对模拟结果进行精度分析。研究结果:对照2007年遥感影像分类得到的实际土地利用分类图,实验模拟结果数量上正确率平均达到88.99%,模拟结果的总体分类精度为86.75%,Kappa系数为0.85。研究结论:基于多类支持向量机的非线性元胞自动机方法具有较高的模拟精度,可以应用于模拟多类土地利用类型之间的演变。

土改后的农民经济(1951-1954)

通过土改和财产的再分配,使以往无地少地的农民成为独立的自耕农,从而具有从事农业再生产的能力,提高了他们的生产积极性。加之国家力量的援助,土改后的黔南农民经济保持了一个较长时间的稳定增长。具体到每一个阶层,其农户经济和劳动心理又有很大差别。实际上,甚至每个小农的形势判断和行为选择都是根据其所处的客观环境作出,在政治安全、经济利益、社区道义等诸多因素中进行权衡。

陆面过程模式CLASS径流模拟的改进和应用

针对陆面过程模式CLASS(Canadian Land Surface Scheme)产流模拟方面的不足,提出考虑壤中流产流机制的产流模拟方案。利用淮河流域能量和水分循环试验(HUBEX)资料,在史灌河流域对改进前后的模型进行了对比试验。结果表明,产流模拟改进方案大大提高了CLASS的径流模拟能力,同时改善了模式对土壤含水量的模拟。

基于OBE-CDIO融合理念的土地资源学课程改革探索

针对土地资源学教学中的短板,在国家一流本科专业建设背景下,融入OBE-CDIO理念,增添思政元素,从加强多学科知识交叉融合、搭建课程信息平台、加强土地资源类竞赛、建立多元化课程考核体系等维度进行改革探索。按照以学生为主体,成果为导向,梳理土地资源利用全过程,塑造学生工程项目思维为目标的课程改革,实现复合型人才培养目标。

Culm characteristics and volume-weight relationship of a forest bamboo(Melocanna baccifera(Roxb.) Kurz) from northeast India

Culm characteristics of Melocanna baccifera, locally ＇muli＇, culms at five different culm ages of 11 girth classes （5-6 to 15-16 cm） were studied from Cachar Dis- trict of southern Assam, northeast India. We recorded internode length, internode diameter, number of internodes per culm, total culm height, total culm green weight and total culm volume of all five culm age classes. Data were gathered on 165 culms, each culm age class containing 33 culms with 3 culms per girth class. Culm height ranged from 3.2 to 15.3 m with highest mean of 9.15 m （in threeyear old culms） and maximum culm height was recorded in four-year old culms. Highest mean and maximum internode length （27.45 and 54.2 cm, respectively）, internode diameter （3.12 and 4.75 cm, respectively） and total culm green weight （5.42 and 12.87 kg/culm, respectively） were recorded in three-year old culms and lowest in current-year culms. Best fitted regression models for all parameters were developed. Significant linear relationships between culm green weight and culm solid volume were documented for all five culm age classes. Their corresponding best-fit regression models were also developed.

基于Landsat8遥感影像的六安市土地利用分类研究

利用遥感数据波段融合技术与图像分类技术,采用Landsat8遥感影像,通过ArcGIS平台,经过数据裁剪、融合、样本管理与在线分类学习,展开六安市部分区域的土地利用分类研究。通过研究,以期为六安市的土地利用分类提供一种科学的监测方法。

Timberland Investing and Private Property Rights in the United States of America

Investments in rural land for agriculture, timber, and other natural resource purposes occur frequently and globally. Fundamental principles of liberty and property found in the United States of America’s (“US”) legal system, from its origins to recent US Supreme Court decisions, continue to positively benefit holders of real estate in the Southern US, through a deep-rooted public policy of supporting private property rights and rural economic development. This stable rule of law enhances the long-term adaptability and sustainability of timberland as an asset class. This article is a commentary. It combines legal research methodology with the observations and conclusions of the authors. Its purpose is to demonstrate that the existence of alienable, documentable ownership, and related property rights create inherent stability and security. These principles form the basis of a culture that is defined by the rule of law and is “open for business.” This business mindset is particularly prevalent in the Southern US.

Computer-aided Pattern Design of Multi-bar Warp Knitted Fabrics

To meet the development trend of multi-bar warp knit-ting machine towards high-speed,advanced technologyand computer control and the requirements of variousproducts with small quantity,there are many researcheson the computer-aided pattern design of multi-barwarp knitted fabrics.In terms of the special propertiesof the computer-aided pattern design of multi-barwarp knitted fabrics,the Object Oriented Program(OOP)programming-Object Windows class Library(OWL)programming is selected.According to thecharacters of the OWL programming,various functionsare defined.Pattern design and technical parameters canbe output,which offers a great convenience for the fac-tory.

用于高分辨率遥感影像地类识别的Deeplabv3+改进模型

在高分辨率遥感影像地类识别上,语义分割网络Deeplabv3+表现优异,但是所需参数非常多,训练时间久。遥感影像中的地类与普通RGB图片中的对象相比颗粒度非常大,其具有更显著的特征以及更少的类别,并不需要过深过大的网络。因此,文中提出了一种基于轻量级网络的语义分割模型(Thin-Deeplabv3+),对Deeplabv3+的编码器进行了改进,利用轻量级膨胀网络(Light and Dilated Network,LDNet)提取输入遥感影像的特征,然后利用膨胀系数分别为2、12、24和36的空洞空间金字塔池化(Atrous Spatial Pyramid Pooling,ASPP)模块加强特征提取。在高分遥感影像数据集(Gaofen Image Dataset,GID)以及DeepGlobe土地覆盖分类挑战数据集(DeepGlobe Land Cover Classification Challenge,DLCCC)上的实验结果表明,Thin-Deeplabv3+的识别精度高于Deeplabv3+,并且所需参数仅约为Deeplabv3+的1/10。

我国南方典型红壤区景观格局对崩岗侵蚀的影响

崩岗是地质构造、地貌条件、气象水文、植被、人类活动等综合作用下形成的一种复合侵蚀地貌,崩岗的形成与发展已严重制约了当地农业生产和社会经济发展。通过调整土地利用结构方式、优化景观格局是防治红壤区崩岗侵蚀的重要手段。如何从斑块类型水平揭示景观格局与崩岗侵蚀的关系,对于控制崩岗侵蚀、提高生态环境效益具有重要意义。以福建省安溪县为例,运用ArcGIS水文分析工具和DEM数据将该区域划分为53个子流域,以崩岗面积与密度为响应变量,景观格局指数为解释变量,采用冗余分析(RDA)法和通径分析法,从斑块类型水平探讨景观格局指数与崩岗面积与密度的影响。结果表明:影响崩岗侵蚀的景观格局指数主要由土地利用类型决定,其中林地的景观格局指数对崩岗特征的解释度最高(63.82%),其次为耕地(49.19%)和建设用地(42.01%);耕地景观类型面积、林地聚集度、建设用地景观形状指数和林地斑块连接度4个指标显著影响崩岗特征,对崩岗特征变化的贡献率分别为51.5%、26.9%、9.2%和6.1%,且4个指标对崩岗特征的累积解释度达到66.2%;通径分析发现耕地景观类型面积、林地斑块连接度、林地边缘密度、林地斑块类型面积百分比和建设用地边缘密度的综合作用对崩岗面积变化和密度变化的解释程度分别为71%和85%,其中耕地景观类型面积和林地斑块类型面积百分比对崩岗面积和崩岗密度的影响最大,通径系数分别是0.499、-0.440和0.608、-0.342。总体而言,科学合理的规划耕地、林地和建设用地的空间布局,提升景观类型整体生态效应,对抑制崩岗侵蚀具有重要意义。研究结果对于科学规划土地利用、控制红壤区崩岗侵蚀具有重要指导意义。

改进三维最大类间方差的SAR图像海陆分割算法

合成孔径雷达(Synthetic Aperture Radar,SAR)是一种在气象条件较差的条件下工作的高分辨率成像雷达。无论在民用还是军事领域,用合成孔径雷达进行海上舰船图像目标检测都能起到关键作用。海陆分割作为一种SAR图像预处理的手段,可以为后续的目标检测、识别与跟踪技术研究奠定良好的基础。本文对包含较复杂岛岸背景的SAR图像的海陆分割算法进行研究,在传统三维最大类间方差算法的基础上提出一种改进的SAR图像海陆分割算法,将原有算法第三维度邻域中值改为Prewitt算子的梯度运算,Prewitt算子适合处理灰度渐变复杂的图像,SAR图像能够更好地进行图像分割。考虑到维度上增加一维会使得算法效率降低,运用分解的思想,将三维最大类间方差拆分成3个一维最大类间方差算法。通过两组SAR图像进行实验,结果表明本文提出的改进三维最大类间方差算法具有可行性,并且在海陆分割效果方面优于一维、二维最大类间方差算法,在运算复杂度方面优于传统的三维最大类间方差算法。

多任务学习孪生网络的遥感影像多类变化检测

精确掌握土地覆盖/利用的变化及变化类型对国土空间规划、生态环境监测、灾害评估等有着重要意义,然而现有大部分变化检测研究主要关注二值变化检测。为此,该文首先提出了一种多任务学习深度孪生网络用于遥感影像的多类变化检测。首先提出面向对象的无监督变化检测方法,选择出新、旧时相影像中最有可能发生变化和最不可能发生变化的区域,并作为多任务学习深度孪生网络的样本;其次,采用多任务学习深度孪生网络模型同时对新、旧时相的土地利用图以及新、旧时相的二值变化图这3个任务模型进行学习和预测;最后,基于模型预测的新、旧时相土地利用图及新、旧时相的二值变化图获取最终的多类变化检测结果。采用第三次全国国土调查的影像数据和相应的土地利用图斑数据对多任务学习深度孪生网络模型进行了测试,结果表明所提出的方法适用于这种在没有变化、未变化样本而有历史专题图的变化检测场景中。

呼伦贝尔草原风蚀坑植物分布空间异质效应

风蚀坑是草原常见的风蚀地貌类型,其发生风蚀同时伴随不同程度的沙埋作用,造成其不同区域植被生长及分布存在一定差异。为明晰草原风蚀坑不同区域的植被组成特征与分布规律,本研究以呼伦贝尔草原处于活跃发展阶段的风蚀坑为研究对象,调查风蚀坑5个不同区域(沙坑、上风向区、左积沙区、右积沙区、下风向区)植物种类及其生长情况,并以周边天然草地为对照(CK),分析风蚀坑对植物空间分布的异质效应,拟为草原风蚀坑发展机制研究及其植被恢复技术提供重要依据。研究表明:(1)风蚀坑与CK相比植物种类显著增加,植物种类达到了42种,隶属于13科34属,CK为17种,隶属于8科16属,但增加的植物种多为沙蓬、兴安虫实等沙生植物。(2)风蚀坑不同区域植物种存在显著的异质性,沙坑主要植物种为菊科,植物种数量较CK分别减少85.42%。上风向处、左积沙区、右积沙区等区域植物种以苋科为主,下风向处以禾本科植物为主,分别增加了47.05%、117.75%、35.29%、29.17%。(3)不同区域植物长势存在较大差异,沙坑、下风向区较CK差异最显著,植株密度降低了99.63%、89.73%,植被盖度降低了84.48%、69.06%,地上生物量降低了93.15%、56.78%。(4)下风向区沙埋覆盖草地面积最大,随着沙坑边缘经过积沙区向草地延伸,植物种类数量逐渐接近CK,重合度可达到52.63%,苍耳、沙蓬等植物消失。

省级国土三调与用地用海分类数据快速转换技术方法探索

为实现大范围的省级国土三调分类数据与用地用海分类数据间的转换,本文采用深度学习技术和人工目视解译方法,根据国土三调分类与国土空间规划用地用海分类对接情况表,对国土三调分类二级类与用地用海分类二级类进行差异对比。首先,分析地类映射关系,研究“一对一”“一对多”地类映射关系的规律与特征,制作“一对一”转换工具,对“一对一”地类进行批量转换;其次,结合遥感影像、地名地址数据、地理国情监测数据、互联网POI等参考数据,采用深度学习技术方法,开展“一对多”地类自动转换方法研究;最后,研究一套半自动的国土三调地类与用地用海地类的转换技术流程,对基于深度学习的自动转换精度进行分析和评价,验证所提方法的可靠性和准确率。研究成果可实现广东全省国土三调地类向用地用海二级类的批量转换,大大提升转换效率,取得良好的效果,所提出的方法流程具有较强的科学性和可操作性。