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陆面模式SSiB耦合TOPMODEL对流域水文模拟影响的数值试验  [PDF]
高原气象 , 2013, DOI: 10.7522/j.issn.1000-0534.2012.00076
Abstract: 为了检验陆面模式SSiB耦合TOPMODEL模型对流域水量平衡模拟结果的影响,用原始SSiB与TOPMODEL按饱和区和非饱和区两种方案耦合的耦合模型(下称SSiBT)进行长江下游青弋江流域水文的数值试验,通过耦合模型与原始SSiB模式模拟结果的比较,并利用流域实测逐日流量和水量平衡资料,揭示了流域水文模拟结果对SSiB耦合TOPMODEL的响应和原因。结果表明:(1)与原始SSiB的模拟结果相比,SSiBT增加了土壤湿度的模拟结果和各层土壤湿度之间的差异,流域蒸散发增加而总径流减小。(2)原始SSiB不能准确地将径流在地表径流和基流之间分配,对于较小的土壤饱和导水率,原始SSiB产生过多的地表径流和洪峰流量;对于较大的土壤饱和导水率又产生过多的基流和明显偏小的洪峰流量。(3)即使土壤饱和导水率大到不会产生超渗产流,由于饱和区的存在,SSiBT在洪水期间也能产生足够大的地表径流,从而形成洪峰流量。由于考虑了地形引起的土壤湿度空间非均匀形成的饱和区产流,SSiBT改善了雨季逐日流量的模拟结果。
2001年~2015年伊犁河谷草地植被覆盖度时空变化特征
Spatiotemporal dynamics of grassland fractional coverage in Yili Valley of Xinjiang from 2001 to 2015
 [PDF]

闫俊杰,黄 辉,崔 东,刘海军,陈 晨
YAN Junjie
,HUANG Hui,CUI Dong,LIU Haijun,CHEN Chen

- , 2017,
Abstract: 基于MODIS NDVI数据,利用像元二分模型反演植被覆盖度,结合DEM数据及差值分析方法对伊犁河谷2001年~2015年草地植被覆盖度的时空变化特征进行了研究.得出如下结论:1) 受持续畜牧超载及气候条件恶化影响,2001年~2015年伊犁河谷草地盖度持续降低,15 a内全区草地平均盖度降低11.09%, 90.04%草地的植被盖度出现不同程度的降低,但主要为降幅〈0.10的轻度降低,1 000~2 250 m海拔范围平均降幅最大;2) 草地盖度变化主要表现在高覆盖草地持续减少,以及盖度降低草地的面积增大和降幅增高,并空间上逐步向高海拔区域延展.3) 得益于草地保护政策的实施,2010年~2015年植被盖度降低速度明显减慢,但其降低总趋势未有改变.
Calibra??o do "simplified simple biosphere model - SSiB" para áreas de pastagem e floresta na Amaz?nia com dados do LBA
Correia, Francis Wagner Silva;Alvalá, Regina Célia dos Santos;Manzi, Ant?nio Ocimar;Gielow, Ralf;Kubota, Paulo Yoshio;
Acta Amazonica , 2005, DOI: 10.1590/S0044-59672005000200017
Abstract: the parameters of the simplified simple biosphere model - ssib were validated and subsequently calibrated for the fazenda nossa senhora aparecida (62o22'w; 10o45's) pasture site and the reserva biológica do jaru (62o22'w; 10o45's) forest site, both located in the state of rond?nia. micrometeorological and hydrological data collected during the dry period of 2001, as part of the large-scale biosphere-atmosphere experiment in amazonia - lba, were used. the results showed that the model simulated well the net radiation, both at the pasture and at the forest. the latent heat flux was super-estimated in both sites. the model sub-estimated the sensible heat flux at the pasture and at the forest, mainly during the night period; notwithstanding, the values for the forest were nearer to the observed ones. with the calibrated parameters, the model generated better estimations of the latent and the sensible heat fluxes, thus better representing the energy partition both at the forest and at the pasture.
Validation of models for predicting milk urea nitrogen concentrations, estimating dry matter intake by the NRC (2001)
Meyer, Paula Marques;Machado, Paulo Fernando;Coldebella, Arlei;Cassoli, Laerte Dagher;Coelho, Karyne Oliveira;Rodrigues, Paulo Henrique Mazza;
Revista Brasileira de Zootecnia , 2012, DOI: 10.1590/S1516-35982012000500026
Abstract: the objective of this study was to validate three different models for predicting milk urea nitrogen using field conditions, attempting to evaluate the nutritional adequacy diets for dairy cows and prediction of nitrogen excreted to the environment. observations (4,749) from 855 cows were used. milk yield, body weight (bw), days in milk and parity were recorded on the milk sampling days. milk was sampled monthly, for analysis of milk urea nitrogen (mun), fat, protein, lactose and total solids concentration and somatic cells count. individual dry matter intake was estimated using the nrc (2001). the three models studied were derived from a first one to predict urinary nitrogen (un). model 1 was mun = un/12.54, model 2 was mun = un/17.6 and model 3 was mun = un/(0.0259 × bw), adjusted by body weight effect. to evaluate models, they were tested for accuracy, precision and robustness. despite being more accurate (mean bias = 0.94 mg/dl), model 2 was less precise (residual error = 4.50 mg/dl) than model 3 (mean bias = 1.41 and residual error = 4.11 mg/dl), while model 1 was the least accurate (mean bias = 6.94 mg/dl) and the least precise (residual error = 5.40 mg/dl). they were not robust, because they were influenced by almost all the variables studied. the three models for predicting milk urea nitrogen were different with respect to accuracy, precision and robustness.
Validation:  [cached]
Mr.Sohan S.Chitlange,Mr. Ajay S. Pawar,Mr.Hemant I. Pawar,Mr.Santosh S. Bhujbal
Pharmaceutical Reviews , 2006,
Abstract: Validation is establishing documented evidence, which provides high degreeassurance that a specific process will consistently produce a product meetingits predetermined specification and quality characteristics.Butvalidation itself does not improve process but assures that the process hasbeen properly developed and is under control.
Impacts of Land Surface on Climate of July and Onset of Summer Monsoon: A Study with an AGCM plus SSiB

Liu Hui,Wu Guoxiong,

大气科学进展 , 1997,
Abstract: To get more insight into the impacts of land surface processes on climate, a simplified biosphere model (SSiB) developed by Sellers and Xue et al. is implemented into the LASG / IAP spectral climate AGCM (R15L9). The new model has been integrated for more than twenty years. The diagnoses of the integration show that the implementing of the land surface processes has greatly improved the simulation of July climate. It is also shown that the seasonal variations of land surface characteristics have great impacts on the onset of summer monsoon, especially the seasonal march of wind at 850 hPa and precipitation over the regions of summer monsoon.
Referees 2001
E Boshoff
Journal of Family Ecology and Consumer Sciences /Tydskrif vir Gesinsekologie en Verbruikerswetenskappe , 2001,
Abstract: Referees 2001
An analysis of a meso-β system in a mei-yu front using the intensive observation data during CHeRES 2002
An Analysis of a Meso-β System in a Mei-yu Front Using the Intensive Observation Data During CHeRES 2002

SUN Jianhu,ZHANG Xiaoling,QI Linlin,ZHAO Sixiong,
SUN Jianhu
,ZHANG Xiaoling,QI Linlin,ZHAO Sixiong

大气科学进展 , 2005,
Abstract: The conventional and intensive observational data of the China Heavy Rain Experiment and Study (CHeRES) are used to specially analyze the heavy rainfall process in the mei-yu front that occurred during 20–21 June 2002, focusing on the meso-β system. A mesoscale convective system (MCS) formed in the warm-moist southwesterly to the south of the shear line over the Dabie Mountains and over the gorge between the Dabie and Jiuhua Mountains. The mei-yu front and shear line provide a favorable synoptic condition for the development of convection. The GPS observation indicates that the precipitable water increased obviously about 2–3 h earlier than the occurrence of rainfall and decreased after that. The abundant moisture transportation by southwesterly wind was favorable to the maintenance of convective instability and the accumulation of convective available potential energy (CAPE). Radar detection reveals that meso-β and-γ systems were very active in the MαCS. Several convection lines developed during the evolution of the MαCS, and these are associated with surface convergence lines. The boundary outflow of the convection line may have triggered another convection line. The convection line moved with the mesoscale surface convergence line, but the convective cells embedded in the convergence line propagated along the line. On the basis of the analyses of the intensive observation data, a multi-scale conceptual model of heavy rainfall in the mei-yu front for this particular case is proposed.
Spatio-Temporal Variation of Grassland in Western Songnen Plain
松嫩平原西部草地的时空变化特征

TANG Jie,LI Zhao-yang,LIN Nian-feng,SUN Ping-an,
汤洁
,李昭阳,林年丰,孙平安

资源科学 , 2006,
Abstract: This paper analyzed temporal and spatial variation of various vegetation fractions and inner configuration of the grassland in western Songnen Plain where ecological environment was fragile based on the remote sensing data and classification of grassland resource with the support of GIS technology.It educes the quantities and characteristics of transformation among higher-coverage grassland,mid-coverage grassland,and lower-coverage grassland and other land use types from 1989 to 2001.The results indicate that the areas of three kinds of grassland are decreasing during 12 years.The transformation proportions to glebe are 77.78%,70.13% and 36.57% respectively,which illuminate that the main reason for the decrease of grassland is human's durative exploitation of grassland.The transformation proportion from grassland to saline-alkalized land increases with the decrease of grassland's vegetation fraction and is 0%,4.62%,and 32.81% for higher-coverage grassland,mid-coverage grassland and lower-coverage grassland,respectively.It shows that a crucial factor for saline-alkalized grassland is vegetation fraction.From the dynamic changing of grassland's inner configuration,we conclude that degenerative characteristic of grassland is from higher-coverage to mid-coverage and from mid-coverage to lower-coverage;moreover,the evolution is almost non-reversible under the current human activities.The degraded grassland is mostly located at the north of Zhenlai County,the south of Taonan City,the north of Tongyu County and the west of Qian'an County.Analysis of saline-alkalized grassland show that the most important reason causing saline-alkalized grassland is the continuous impact of human activities,and the status of mid-coverage grassland is the key affecting holistic quantity of grassland and the outspread speed of saline-alkalized grassland.Therefore,the only way for socio-economic and ecological environmental sustainable development is to utilize grassland resource soundly and restore the saline-alkalized grassland synthetically.At the end,the authors put forward the measures of ecological environmental restoration and grassland's sustainable development based on rational utilization of existing grassland resource and integrative prevention and rehabilitation of saline-alkalized grassland in research area.
Grassland degradation in Northern Tibet based on remote sensing data

GAO Qingzhu,LI Yu&rsquo,e,WAN Yunfan,LIN Erda,XIONG Wei,JIANGCUN Wangzha,WANG Baoshan,LI Wenfu,

地理学报 , 2006,
Abstract: This study selected vegetation cover as the main evaluation index, calculated the grassland degradation index (GDI) and established the remote sensing monitoring and evaluation system for grassland degradation in Northern Tibet, according to the National Standard (GB19377-2003), based on the remote sensing data such as NDVI data derived from NOAA/AVHRR with a spatial resolution of 8 km of 1981-2000, from SPOT/VGT with a spatial resolution of 1 km of 2001 and from MODIS with a spatial resolution of 0.25 km of 2002-2004 respectively in this area, in combination with the actual condition of grassland degradation. The grassland degradation processes and their responses to climate change during 1981-2004 were discussed and analyzed in this paper. The result indicated that grassland degradation in Northern Tibet is very serious, and the mean value of GDI in recent 20 years is 2.54 which belongs to the serious degradation grade. From 1981 to 2004, the GDI fluctuated distinctly with great interannual variations in the proportion of degradation degree and GDI but the general tendency turned to severe-grade during this period with the grassland degradation grade changed from light degraded to serious degraded in Northern Tibet. The extremely serious degraded and serious degraded grassland occupied 1.7% and 8.0% of the study area, the moderate and light degraded grassland accounted for 13.2% and 27.9% respectively, and un-degraded grassland occupied 49.2% of the total grassland area in 2004. The grassland degradation was serious, especially in the conjunctive area of Naqu, Biru and Jiali counties, the headstream of the Yangtze River lying in the Galadandong snow mountain and glaciers, the area along the Qinghai-Tibet highway and railway, and areas around the Tanggula and Nianqingtanggula snow mountains and glaciers. So the snow mountains and glaciers as well as their adjacent areas in Northern Tibet were sensitive to climate change and the areas along the vital communication line with frequent human activities experienced relatively serious grassland degradation.
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