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1.
Carlos Roberto Sanquetta Ana Paula Dalla Corte Allan Libanio Pelissari Margarida Tomé Greyce Charllyne Benedet Maas Mateus Niroh Inoue Sanquetta 《Carbon balance and management》2018,13(1):20
Background
We analyzed the dynamics of carbon (C) stocks and CO2 removals by Brazilian forest plantations over the period 1990–2016. Data on the extent of forests compiled from various sources were used in the calculations. Productivities were simulated using species-specific growth and yield simulators for the main trees species planted in the country. Biomass expansion factors, root-to-shoot ratios, wood densities, and carbon fractions compiled from literature were applied. C stocks in necromass (deadwood and litter) and harvested wood products (HWP) were also included in the calculations.Results
Plantation forests stocked 231 Mt C in 1990 increasing to 612 Mt C in 2016 due to an increase in plantation area and higher productivity of the stands during the 26-year period. Eucalyptus contributed 58% of the C stock in 1990 and 71% in 2016 due to a remarkable increase in plantation area and productivity. Pinus reduced its proportion of the carbon storage due to its low growth in area, while the other species shared less than 6% of the C stocks during the period of study. Aboveground biomass, belowground biomass and necromass shared 71, 12, and 5% of the total C stocked in plantations in 2016, respectively. HWP stocked 76 Mt C in the period, which represents 12% of the total C stocked. Carbon dioxide removals by Brazilian forest plantations during the 26-year period totaled 1669 Gt CO2-e.Conclusions
The carbon dioxide removed by Brazilian forest plantations over the 26 years represent almost the totality of the country´s emissions from the waste sector within the same period, or from the agriculture, forestry and other land use sector in 2016. We concluded that forest plantations play an important role in mitigating GHG (greenhouse gases) emissions in Brazil. This study is helpful to improve national reporting on plantation forests and their GHG sequestration potential, and to achieve Brazil’s Nationally Determined Contribution and the Paris Agreement.2.
The temporal change of the rotation vector of a rotating body is, in the first order, identical in a space-fixed system and
in a body-fixed system. Therefore, if the motion of the rotation axis of the earth relative to a space-fixed system is given
as a function of time, it should be possible to compute its motion relative to an earth-fixed system, and vice versa. This
paper presents such a transformation. Two models of motion of the rotation axis in the space-fixed system are considered:
one consisting only of a regular (i.e., strictly conical) precession and one extended by circular nutation components, which
are superimposed upon the regular precession. The Euler angles describing the orientation of the earth-fixed system with respect
to the space-fixed system are derived by an analytical solution of the kinematical Eulerian differential equations. In the
first case (precession only), this is directly possible, and in the second case (precession and nutation), a solution is achieved
by a perturbation approach, where the result of the first case serves as an approximation and nutation is regarded as a small
perturbation, which is treated in a linearized form. The transformation by means of these Euler angles shows that the rotation
axis performs in the earth-fixed system retrograde conical revolutions with small amplitudes, namely one revolution with a
period of one sidereal day corresponding to precession and one revolution with a period which is slightly smaller or larger
than one sidereal day corresponding to each (prograde or retrograde) circular nutation component. The peculiar feature of
the derivation presented here is the analytical solution of the Eulerian differential equations. 相似文献
3.
PENG Lin LIU Yanxiong ZHOU Xinghua WU Yongting 《地球空间信息科学学报》2006,9(2):99-102
IntroductionIn GPS data-processing, the most accurate andpopular method is to solve the unknown parametersbased on a GPS network which includes many GPSsites. This mode is always called network-solution.The network-solution makes use of the spatial geom-e… 相似文献
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This study investigates urbanization and its potential environmental consequences in Shanghai and Stockholm metropolitan areas over two decades. Changes in land use/land cover are estimated from support vector machine classifications of Landsat mosaics with grey-level co-occurrence matrix features. Landscape metrics are used to investigate changes in landscape composition and configuration and to draw preliminary conclusions about environmental impacts. Speed and magnitude of urbanization is calculated by urbanization indices and the resulting impacts on the environment are quantified by ecosystem services. Growth of urban areas and urban green spaces occurred at the expense of cropland in both regions. Alongside a decrease in natural land cover, urban areas increased by approximately 120% in Shanghai, nearly ten times as much as in Stockholm, where the most significant land cover change was a 12% urban expansion that mostly replaced agricultural areas. From the landscape metrics results, it appears that fragmentation in both study regions occurred mainly due to the growth of high density built-up areas in previously more natural/agricultural environments, while the expansion of low density built-up areas was for the most part in conjunction with pre-existing patches. Urban growth resulted in ecosystem service value losses of approximately 445 million US dollars in Shanghai, mostly due to the decrease in natural coastal wetlands while in Stockholm the value of ecosystem services changed very little. Total urban growth in Shanghai was 1768 km2 and 100 km2 in Stockholm. The developed methodology is considered a straight-forward low-cost globally applicable approach to quantitatively and qualitatively evaluate urban growth patterns that could help to address spatial, economic and ecological questions in urban and regional planning. 相似文献
6.
XU Junfeng HUANG Jingfeng 《地球空间信息科学学报》2006,9(2):108-111
IKONOS image has been wildly used in city planning, precision agriculture and emergence response. However, the accuracy of IKONOS Geo product is limited due to distortion caused by terrain relief. Orthorectification was performed to remove the distortion and the impact of different DEM on orthorectification were evaluated. 38 ground control points （GCPs） and 25 independent check points （ICPs） were collected. DEMs were generated from 1 ： 10 000 and 1 ： 50 000 topographic maps. Results show that RMS error at the check points is 1. 554 0 m using DEM generated from 1 ： 10 000 topographic map, which can meet the accuracy requirement of IKONOS Precision product （1.9 m RMSE）. While RMS error is 2. 572 4 m using DEM generated from 1 ： 50 000 topographic map. 相似文献
7.
Capturing spatial population distribution can offer useful information for urban planning to promote reasonable population distribution and allocate urban resource. Agent-based model (ABM) based on the modeling idea of “bottom-up” can offer the ability to simulate the complex individual behaviors that generate spatial population distribution. Previous ABMs were unable to be extended for simulation of spatial population distribution at a fine scale due to the shortage of fine characterization of the urban environment and the calibration of agents' behavior. This study filled these gaps by proposing a genetic algorithm-ABM (GA–ABM) for fine-scale simulation of spatial population distribution in a manufacturing metropolis. In this model, the employment and residential choice behaviors of agents were defined by the labor economic theory and discrete selection model. Multisource geospatial big data such as enterprise points-of-interest big data and building footprints data were used to finely characterize the labor market and urban environment to reflect the impact of agents' employment choices on their residential decision. Furthermore, the grid-scale population investigation big data were combined with the GA to calibrate the agents' residential decision behaviors. The proposed model was used in Dongguan, the typical manufacturing metropolis in China. As a comparison, the expert-experience-based method-ABM (EEBM–ABM) was also conducted by using the same data set. Through the comparison of the results produced by these two models, it was demonstrated that the model coefficient calibrated by GA could effectively reflect the agents' residential decisions. The calibrated GA–ABM is more capable than EEBM–ABM in simulating spatial population distribution in a manufacturing metropolis. Hence, the proposed model can be used to simulate spatial population distribution in a manufacturing metropolis which helps the urban planner to conduct scientific urban planning. 相似文献
8.
LIU Shaochuang LU Pingli LIU Donghui JIN Peidong Institute of Remote Sensing Applications Chinese Academy of Sciences Datun Road Chaoyang District Beijing China. 《地球空间信息科学学报》2007,10(1):51-56
For centuries, explorers and scientists from different countries had made their own conclusions on the source of the Mekong. However, the geographic source of the Mekong is still arguable because of the complexity of the Mekong source water system, inaccessible environment and the varied technologies used by those explorers and scientists. The satellite remote sensing technology has been used to pinpoint the source of the Mekong, associated with the on-the-spot investigations made by the authors in June 1999 and September 2002. The actual length of the Mekong has also been calculated. 相似文献
10.
部机关各司局、各派驻地方的国家土地督察局、中国地质调查局及部其他直属单位:
《落实(关于全面推进政务公开工作的实施意见)分工方案》已经部领导审定,现印发给你们,请结合本单位工作实际和开展“责任落实年”活动要求,认真抓好落实. 相似文献
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Andrew U. Frank 《Journal of Geographical Systems》2000,2(1):99-105
Geographical Information Science is essentially computational geography and has its own research program, namely all aspects
of formal models for spatial natural processes and the interaction of humans with the environment in space and time. This
is not a question of technology and technology-related research; but technology influences what questions can be researched
effectively. Collection of data in the field and the simulation of field experience through Virtual Reality are just two questions
of how spatial reality and human experience are linked. The focus on human spatial cognition is similarly found in software
engineering for interoperable Geographic Information Systems. 相似文献
13.
LIU Shaochuang LU Pingli LIU Donghui JIN Peidong 《地球空间信息科学学报》2007,10(1):51-56
For centuries, explorers and scientists from different countries had made their own conclusions on the source of the Mekong. However, the geographic source of the Mekong is still arguable because of the complexity of the Mekong source water system, inaccessible environment and the varied technologies used by those explorers and scientists. The satellite remote sensing technology has been used to pinpoint the source of the Mekong, associated with the on-the-spot investigations made by the authors in June 1999 and September 2002. The actual length of the Mekong has also been calculated. 相似文献
14.
In this paper,factors lead to changes ande what changes should be considered are firstly discussed.then changes to be represented by set theory is given.Twelve basic change types are described in detail.At last the paper points out that the change between geoobjects and pixels in images is not all corresponging and it causes the difficulty of accurate and robust change detection techniques. 相似文献
15.
Abstract The sensitivity of microwave sensors to changes in the complex dielectric constant of soil/water mix with change in water content has been used in several studies for soil moisture estimation and in the detection of wetlands. In the study, reported here, an attempt has been made to delineate various categories of wetlands, namely ‘bils’ (acquaculture ponds), lakes/ponds, creeks, and mangroves through visual interpretation of ERS‐1 SAR images acquired on 29th April, 1993 over part of Sundarban delta, abutting Bay of Bengal. An overall accuracy of 91.2% with respect to delineation of wetlands has been achieved. Further, the cloud penetration and day‐and‐night observation capability of ERS‐1 SAR, though well known, is also illustrated. 相似文献
16.
ZHENGZhaobao 《地球空间信息科学学报》2002,5(1):1-6
In the photogrammetry,some researchers have applied genetic algorithms in aerial image texture classification and reducing hyper-spectrum remote sensing data.Genetic algorithm can rapidly find the solutions which are close to the optimal solution.But it is not easy to find the optimal solution.In order to solve the problem,a cooperative evolution idea integrating genetic algorithm and ant colony algorithm is presented in this paper.On the basis of the advantages of ant colony algorithm,this paper proposes the method integrating genetic algorithms and ant colony algorithm to overcome the drawback of genetic algorithms.Moreover,the paper takes designing texture classification masks of aerial images as an example to illustrate the integration theory and procedures. 相似文献
17.
《地球空间信息科学学报》2002,(4)
1 .ＧｅｏｍａｔｉｃｓａｎｄＩｎｆｏｒｍａｔｉｏｎＳｃｉｅｎｃｅｏｆＷｕｈａｎＵｎｉｖｅｒｓｉｔｙ(Ｂｉｍｏｎｔｈｌｙ) ,ａｎａｃａｄｅｍｉｃｐｅｒｉｏｄｉｃａｌｏｒｉｇｉｎａｔｅｄｆｒｏｍＪｏｕｒｎａｌｏｆＷｕｈａｎＴｅｃｈｎｉｃａｌＵｎｉｖｅｒｓｉｔｙｏｆＳｕｒｖｅｙｉｎｇａｎｄＭａｐｐｉｎｇ ,ａｉｍｓａｔｅｘｔｅｎｄｉｎｇｉｎ ｔｅｒｎａｔｉｏｎａｌａｃａｄｅｍｉｃｅｘｃｈａｎｇｅｓｏｆａｄｖａｎｃｅｄｒｅｓｅａｒｃｈｒｅｓｕｌｔｓｉｎｓｕｒｖｅｙｉｎｇａｎｄｍａｐｐｉｎｇ .Ｉｔｃｏｖｅｒｓｔ… 相似文献
18.
LIN Xueyuan XU Jin ZHOU Min 《地球空间信息科学学报》2007,10(3):177-180
When SINS (strap-down inertial navigation system) is combined with GPS, the observability of the course angle is weak. Although the course angle error is improved to some extent through Kalman filtering, the course angle still assumes a divergent trend. This trend is aggravated further when using low-cost and low-accuracy SINS. In order to restrain this trend, a method that uses AHRS to substitute for SINS course angle information is put forward aimed at the hardware component characteristic of the low-cost and low-accuracy SINS including AHRS (attitude and heading reference system) and IMU (inertial measurement unit). Real static and dynamic experiments show that the method can restrain the divergent trend of the navigation system angle effectively, and the positioning accuracy is high. 相似文献
19.
The multispectral and multitemporal analysis of the spectral response of rice has made it possible to determine at which point in the vegetative cycle of rice it is best to make an inventory, together with the usefulness of the normalized‐difference vegetation index for such an inventory. The results could be usefully included in any classification procedure of the TM image in order to make the inventory in a systematic way. In this case a supervised classification of the image has been made which assumes a Gaussian behaviour for each spectral class. The results obtained are, for the most part, consistent with those obtained by using traditional methods. 相似文献
20.
Processing of Laser Scanner Data and Extraction of Structure Lines Using Methods of the Image Processing 总被引：3，自引：0，他引：3
SUILi-chun 《测绘学报》2004,33(1):63-70
激光扫描数据提供了一种新的手段用于获取高精度的数字地形表面模型. 原始的航空激光扫描数据表达的是一些非规则分布的"点云", 这些非规则分布的点需要进行有效的事后处理. 这种事后处理有2个目的:一是将那些分布在地表面上的点(即地面点)与分布在非地表面上的点(譬如树木、房屋或汽车上的点, 即非地面点)进行有效的分离;二是从分离后的地面点中提取结构线, 用于建立高精度的数字地面模型. 作者发展了一系列的基于数字形态学理论和稳健参数估计理论的方法用于分离和探测地面点. 这里所介绍和开发的提取结构线的算法建立在数字图像处理和表面曲率理论的基础上. 这些算法同样可以扩展地用于其他领域. 所介绍的基于数字图像处理理论处理原始的航空激光扫瞄数据和提取结构线的方法取得了很好的结果. 这一结论可以在本文中通过一系列的插图得到有力的证明. 相似文献