Based on this and considering: land use has contacts with soil nutrient; the development of ecology and agrology has already formed the inter-dynamic relation in the last few years, the author sprouted a new idea that the study on land use is carried out in another way. That is to say, land use patterns are designed combining land use modes, soil nutrient with other respects and according as landscape ecology in order to land sustainable use.

在此基礎之上人人看人人靠，并鑒于以下兩點：土地利用與土壤養(yǎng)分有著密切的聯(lián)系黄色羞羞网站；近些年來免费A级特黄真人大片，生態(tài)學和土壤學的發(fā)展已經形成了互動的關系香港性生活视频，筆者提出一條新的思路：換個角度入手來合理配置土地利用四房色播久久，即將土地利用方式一级A片黄片免费、土壤養(yǎng)分和其它方面結合起來，依據景觀生態(tài)學原理丰满巨肥大屁股BBW动态图，通過土地生態(tài)設計來尋求土地利用優(yōu)化模式91在线精品免费一区欧美直播，保證土地利用的可持續(xù)性。

The Farming-pastoral Zone in North China was separated into 8 Eco-regions according to the known Eco-region. The dissertation analyzed the regional differences of land use changes from three aspects on dynamic degree , land use degree and the change direction (1)On land use dynamic degree, the dynamic degree of the cropland was the highest in North warm temperate deciduous broad-leaved forest and the lowest in temperate forest steppe; forest land's was the highest in alpine meadow and the lowest in warm temperate forest steppe; grassland's was the highest in temperate forest steppe-bunchgrass steppe and the lowest in alpine meadow; other land's was the highest in North warm temperate deciduous broad-leaved forest－the Huang-Huai-hai plain and the lowest in warm temperate bunchgrass steppe.

結合已有的自然生態(tài)區(qū)的劃分国内精品一级无码免费播放费，將我國北方農牧交錯帶劃分為8 個自然生態(tài)區(qū)亚洲综合春色另类，選取土地利用動態(tài)度、土地利用程度以及土地利用變化方向等3 個方面的指標對研究區(qū)進行了區(qū)域分異規(guī)律的研究免费网站在线观看深夜视频，結果如下：（1）耕地動態(tài)度北暖溫帶落葉闊葉林生態(tài)區(qū)——北部山地丘陵區(qū)最大jiZZjiZZjiZZ18中国，溫帶森林草原生態(tài)區(qū)最小日韩在线观看视频网站上；林地的動態(tài)度高寒草甸生態(tài)區(qū)最大多人伦交性欧美在线观看，暖溫帶森林草原叢生禾草草原生態(tài)區(qū)——東南森林草原區(qū)最小欧美黄色爽死了,；草地動態(tài)度溫帶森林草原——叢生禾草草原生態(tài)區(qū)最大亚洲精品国产AⅤ综合第一，高寒草甸生態(tài)區(qū)最小鸥美多人××视频；其他用地的動態(tài)度北暖溫帶落葉闊葉林生態(tài)區(qū)——黃淮海平原區(qū)最大淫荡视频网址，暖溫帶森林草原叢生禾草草原生態(tài)區(qū)—西北叢生禾草草原區(qū)最小。

Supported by the ESCAP pilot project on integrated land and water resources management in arid areas using remote sensing and GIS (ESCAP 5-4-401), the land and water resources optimization model was developed and an integrated land and water resources management system based on remote sensing and GIS was designed and developed in this paper.

本文結合聯(lián)合國亞太經社理事會示范項目"利用遙感與GIS技術進行干旱區(qū)水土資源綜合管理"（Pilot project on integrated land and water resources management in arid areas using remote sensing and GIS，ESCAP 5-4-401）永久黄网站色视频免费观看w下载，針對我國廣大的干旱半干旱區(qū)水土資源綜合管理的實際需要黄色视频永久免费看，詳細討論了基于遙感與GIS的干旱半干旱地區(qū)水土資源綜合管理系統(tǒng)的設計思想、目標看美女被操的平台免费观看、結構與功能及系統(tǒng)開發(fā)中的關鍵技術黄色网站国产免费。

Freezing soil is a natural phenomina in cold and mountain areas, which has great impact on the regional climate, water cycle, and water balance. The land surface process in the condition of soil freezing and thawing is one of the most important process in the area. This paper firstly reviews the present study on land surface process in the condition of soil freezing and thawing, especially the development after the the hydrological land surface model introduced into the study of General Circulation Model, then introduces the undergoing international research project, such as Project for Intercomparison of Land-surface Parameterization Schemes and Cold Land Process Field Experiment by NASA, and finally analyses and puts forward the future research field and topics.

凍土是全球中高緯地區(qū)和高山地帶普遍存在的自然現(xiàn)象，它對全球以及區(qū)域性氣候99re在线热播、水循環(huán)免费黄色网站视、水平衡等都有著巨大的影響，土壤凍融條件下的陸面過程正是這種影響的重要環(huán)節(jié)黄色a片视频网导航，介紹了土壤凍融條件下陸面過程的研究現(xiàn)狀欧美国产日韩综合精品一区二区，特別是在大氣環(huán)流模型中引入水文陸面模型以來陸面過程研究的迅猛發(fā)展，對現(xiàn)在國際上正在進行的考慮凍土的陸面過程研究項目青春草在线精品视频免费观看，如陸面過程參數化比較計劃的第二階段第五期PILPS (2E)以及美國NASA的寒區(qū)陸面過程實地試驗計劃也進行了介紹国产91精品黄视频，并在此基礎上對土壤凍融條件下陸面過程的發(fā)展趨勢進行了分析。

On the basis of a great deal of information, several general problem on land sarface process parametrization for a global circulation model and its history of development are described. The Bucket model, EARTH, ISBA and SiSPAT models are respectively expounded, and the situation of studies on land surface process parametrization is summarized. China is a participating country of the international geosphere-biosphere program and the study on circulation of global energy and moisture, and has put forward some valuable soil-vegetation-atmosphere models for land surface process parametrization. which results in effective studies on vegetation indexes.

在大量資料基礎上超碰激情，敘述了大氣環(huán)流模式陸面過程參數化方案的一般問題及其發(fā)展歷程黄色网站下免费观看，分別闡述了水桶模式、EARTH模式丁香五月婷婷激情四射、ISBA模式和SiSPAT模式久久福利亚洲一区二区三区；總結了在陸面過程參數化方面的研究狀況，我國參與了國際地圈生物圈計劃和全球能量與水分循環(huán)的研究欧美在线免费不卡视频，特別是在陸面過程的參數化研究方面欧美最猛性XXXXX潮喷视频，提出了一些有價值的土壤—植物—大氣模式，對植被指數進行了有成效的研究美女黄色片在线免费观看。

With the case study on Wanzhou in the three-gorges reservoir area, it had been studied and analyzed that the potentialities of exploitation and use on land and ecological safety by established land use database, and it had been revealed that serious loss of water and erosion of soil, ecological environment fragility, the water conservancy project submergence a large amount of land, arrannements of the numerous immigrations need a large amount of land, contradictory remarkableness among human and land, and the latent crisis by extensive management land were main crises and questions of the land use.

利用建立的土地利用現(xiàn)狀數據庫131美女爱做视频午夜电影，以三峽庫區(qū)最大淹沒區(qū)萬州為研究對象，對庫區(qū)土地開發(fā)利用潛力及生態(tài)安全性進行了分析和研究性欧美XXXX一XXXX极品。揭示了庫區(qū)土地資源利用中存在的主要危機是水土流失嚴重一级黄久久、生態(tài)環(huán)境脆弱，三峽工程淹沒土地多黄色91在线国产、移民遷建占地比重大全免费午夜一级毛片爽爽爽爽、人地矛盾加劇及粗放經營土地帶來的安全隱患等問題。

By analyzing the cultivated land data from different sources in different phases after 1949,the paper considers the statistics with more errors happens during 1960-1985.According to the systematic data on land use gathered in the 1996 survey,based on reverse deduction of the cultivated land area from 1986 to 1996,and deduction of the cultivated land area from 1960 to 1985 by stages by employing yield of grain,this paper redescribed the actual changing trend and character of Chinese cultivated land and analyzed the driving force of the policy relative to cultivated land to cultivated land area change.

針對該問題曰批日韩在线观看，論文對1949～2003年不同時期不同來源的耕地數據系列進行分析美欧曰韩精品人妻无码视频，認為統(tǒng)計數據存在問題較多的時期為1960～1985年，并采用糧食產量對耕地面積進行了分時期的反演国产福利在线观看精品免费91啪，對于1986～1996年間的耕地數量則按照全國土地利用詳查統(tǒng)一到1996年的結果再進行反推天天插狠狠干，由此重新刻畫建國以來中國耕地資源數量變化的趨勢和特征丁香综合视频露脸开，并結合不同時段耕地相關政策對耕地數量變化的驅動作用進行分析。

By analyzing the cultivated land data from different sources in different phases after 1949,the paper considers the statistics with more errors happens during 1960-1985.According to the systematic data on land use gathered in the 1996 survey,based on reverse deduction of the cultivated land area from 1986 to 1996,and deduction of the cultivated land area from 1960 to 1985 by stages by employing yield of grain,this paper redescribed the actual changing trend and character of Chinese cultivated land and analyzed the driving force of the policy relative to cultivated land to cultivated land area change.

針對該難題黄网站在线永久免费播放，論文對1949～2003年不同時期不同來源的耕地數據系列進行分析黄色网站毛片，認為統(tǒng)計數據存在問題較多的時期為1960～1985年，并采用糧食產量對耕地面積進行l(wèi)e分時期的反演18岁以上禁止看的污视频在线观看，對于1986～1996年間的耕地數量則按照全國土地利用詳查統(tǒng)一到1996年的結果再進行反推毛片网址站，由此重新刻畫建國以來中國耕地資源數量變化的趨勢和特征，并結合不同時段耕地相關政策對耕地數量變化的驅動作用進行分析aa视频网站在线。

According to the systematic data on land use gathered in the 1996 survey,based on reverse deduction of the cultivated land area from 1986 to 1996,and deduction of the cultivated land area from 1960 to 1985 by stages by employing yield of grain,this paper redescribed the actual changing trend and character of Chinese cultivated land and analyzed the driving force of the policy relative to cultivated land to cult

結果表明免费一级AV浏览器在线观看，1949年以來中國耕地資源數量呈現(xiàn)波動性變化，但在1979年之前總體上是增加的黄色在线视频平台a，自20世紀80年代起呈現(xiàn)緩慢下滑欧美一级AA大片片免费看视频，1999年后由于生態(tài)退耕等原因引起耕地數量迅速減少，由此導致的中國糧食安全問題與耕地安全問題值得關注免费A片在线播。

According to the models of land use dynamic change, the research on the dynamic change on land use quantity, space structure and land use degree were carried during 1989 and 2001. The results of the research indicated that the area of cultivated land and saline land increased, and the area of meadow, water areas and wetland reduced within 12 years; The variety ratio of cultivated land, meadow, water areas and saline land changed relatively great; and variety ratio of forestland, land used for resident, industrial and mining changed more steady; The land use degree presented a reducible tendency.

研究結果表明国产特级黄色操逼毛片，吉林西部在12年內耕地和鹽堿地面積增加，草地男同污视频免费在线观看、水域和濕地面積減少；總體上国产一级毛片视频无码网站，耕地黄色伊人、草地、水域和鹽堿地的土地利用變化率較大亚洲毛片av男人的天堂，林地成品直播大全免费观看网站下载、居民、工礦用地和濕地變化較平穩(wěn)日韩医生无码视频播放网站； 12年間土地利用程度呈減小趨勢XXⅩ性欧美视频，全區(qū)十個縣市中只有白城和扶余的土地利用處于發(fā)展期，土地生態(tài)環(huán)境相對較好久久久这里只有精品首页，而其他地區(qū)由于土地生態(tài)環(huán)境呈現(xiàn)不同程度的惡化成人资源网亚洲电影在线观看网站，導致可開發(fā)利用的土地資源逐年較少，土地利用潛力小黄色毛片黄色网站。