And understanding and studying the spectral features and variation rules of geo - targets in the experimental area, raising that it is the basis of geo - targets information collection with imaging spectrometer data to understand spectral features and variation rules of geo - targets, realizing that in a great extent spectral - integrated - form - based classification method can remove the phenomenon of " different spectrum with same objects " resulted from reflection ratio curve translation because of the angle change among sensor, targets and observation direction, and the average and variance images can be introduced to solve the problem of two kinds of geo - target with similar spectral forms and much different values of whole reflection ratio. it is suggested that " red edge " range bands of vegetation, which has close relationship with vegetation cover and biomass, is the main characteristic bands and important basis for careful vegetation classification and quantitative retrieval, and pixel - based derivative spectral analysis is very useful for removing the effects of soil background values and quantitatively retrieving vegetation biomass and cover. the remote sense quantitative retrieval model is developed for main appraisable factors of desertification monitoring assessment with imaging spectrometer data and then the applicability of model is analyzed
研究結果如下：首先針對荒漠化地區的地物特徵，對高光譜數據不同波段的數據質量、波段組合進行了評價，提出了適用於荒漠化監測的基本波段選擇集；初步了解和掌握了研究地區的地物光譜特性及變異規律，進一步明確了掌握地物光譜特徵和變異規律是用成像光譜儀數據提取地物信息的基礎；發現了基於光譜整體形狀的分類方法在很大程
度上能夠消除由於傳感器、地物目標觀測方向之間的角
度變化引起的反射率曲線整體平移的「同物異譜」現象，對于譜形相似而整體反射率的值相差較大的兩類地物，通過引入均值和方差圖像參與分類得到解決；研究還表明在植被「紅邊」范圍內的波段是進行荒漠化監測的主要特徵波段，這些波段與植被生物量和
蓋度都有密切的關系，是開展精細植被分類研究和植被定量反演的重要基礎；像元的導數光譜分析可以消除土壤背景的影響，是進行植被生物量和
蓋度定量反演的有力工具；建立了荒漠化監測主要評價因子的定量反演模型，並分析了模型的適用性。
Herbs bourgeoned with a high density and a low coverage in early july. with the coming of rain season, the velocity of growth in herbs enhanced with the higher coverage in august. in september, the growth of herbs stopped and the density and coverage of herbs descended
草本植物在7月初萌發，平均密
度大，但植株較小，
蓋度也小;隨著降雨量的增加，在8月份一一草本植物的快速生長期，草本植株個體長大，平均
蓋度達最大值，但是密
度卻有所下降;到了9月中下旬基本成熟並逐漸死亡，
蓋度和密
度均下降。
The results show that the main foctor that affects the natural regeneration is elevation, and the coverages of litter and brushwood were next
結果表明，影響該區森林天然更新的主要因素是海拔高
度，其次是灌木層
蓋度和枯落物層的
蓋度。
Then based on the method of dimidiate pixel model, the current model is improved, and the model of deriving vegetation fraction from normalized difference vegetation index ( ndvi )
然後在像元二分模型的基礎上對已有模型進行改進，建立用ndvi歸一化植被指數估算植被覆
蓋度的模型。
Minqin desert area belongs to the typical droughty desert shrubs and its vegetation coverage only comes to 5 % desert climate and its 15 %
摘要民勤沙區屬于典型的乾旱荒漠氣候，植被以灌木荒漠為主，
蓋度一般只有5 % ~ 15 % 。
Surfaces for sports areas - method of test - determination of ground cover of natural turf
運動場表面.試驗方法.天然草皮地面覆
蓋度測定
The results showed that the density and coverage of shrubs growing in the intervale of sand fixing region were biggest, but those of herbs were smallest. in contrast, the density and coverage of shrubs growing in the lee slope of dune were smallest, but those of herbs were biggest
不同地形條件下，丘間低地灌木植物密
度、
蓋度最大，草本植物的密
度和
蓋度卻最小;背風坡灌木植物密
度、
蓋度最小，而草本植物的密
度、
蓋度卻最大。
The paper studied comprehensive performance of ten different mixed lawn grass at chengdu city, the characteristics of lawny planting speed, greensward density, leaf texture, green vegetation index, disease resistance, the cover age, uniformity and comprehensive quality were evaluated
摘要對10個混播組合草坪草在成都地區的綜合表現進行了研究，分別對建植速
度、密
度、葉片質地、綠
度、抗病性、
蓋度、均一性、綜合評定共8項質量進行綜合評價。
The great bustard is polyphagia bird, but it feeds mainly on plants. the feeding field habitat selection relate with that whether the grassland burn or not last year. the important factors that determine the feeding field selection are the plant species, vegetative cover score. density hemerrocallis minor and the density of pedacularis sp. on burning grasslandsjthe density of vegetation. insects quanlity. plant species richness and the height of plant are the main factors that determine the feeding field selection on unburning grasslands
大鴇是雜食性鳥類，但以植物性食物為主。對于取食地的選擇往往跟草原上一年是否被火燒過有關。在火燒地，植物種類數、植被
蓋度、小黃花菜密
度和蒿密
度是取食地選擇的重要因素；在非火燒地，植被密
度、昆蟲數量、植物物種豐富
度及植物高
度在大鴇取食地選擇中發揮重要作用。
The classified result show that the grass land of this region retrogressed badly in 2000 : the appreciable retrogression proportion of the grass land is 15 %, the moderate retrogression proportion is 15 % ; the serious retrogression proportion is 8 % ; the area of desert is 2755. 27km2 and the proportion is 19 %, which had increased about 88. 9 % in eight years
植被覆
蓋度分類結果顯示， 2000年該地區草地退化比較嚴重： 21草地輕
度退化， 15的草地中
度退化， 8的草地重
度退化，土地沙化面積為2755 . 27km ~ 2 ，比1992年增加了88 . 9 。
Moderate and rotational grazing can do some good to the development of leymus secalimus population, and ca n ' t result in desertification in grassland
適
度的輪牧可促進賴草種群的發育，增加植被
蓋度，不會導致荒漠化。
In this paper, on the basic theories foundation study of summary people of the past, aiming directly at whether the shelter forest can deposit the sand and how powerful it can. we select the oasis in ulan buh desert as the study plot, and study the function of the shelter forest reduce the " sand " and " dust ". we draw the following conclusion. first, in the fixed and semifixed sand lands, which grow the natural sand - binding plants, the coverage of plant in the fixed and semifixed sand land is 26. 4 % and 10. 3 %, respectively, the amount of sand drift decrease 93. 38 % and 81. 91 % comparing with the migratory sand land which have no plant coverage in the same wind speed and the range of 0 - 40cm above the ground
本文以前人的研究為基礎針對「防護林體系是否有降解作用，有多大的降解作用」這一問題以烏蘭布和沙漠邊緣的防護林體系為研究對象，研究了防護林體系對「沙」 、 「塵」的降解作用，得出以下結論： （ 1 ）在距離地表0 - 40cm范圍內，同一風速下生長有天然固沙植物，植被
蓋度分別為26 . 4 、 10 . 3的固定、半固定沙地上，地表起沙量分別比無植被生長的流動沙地降低了93 . 38 、 81 . 91 。
And the thin films have few defects and a uniform stoichiometry, and also excellent electrical and optical properties
制備的cds薄膜均勻、緻密、覆
蓋度好、薄膜的物理性質優良。
Meanwhile, an artificial imitation rainfall system was developed in order to study the characteristics of city underlying surface and make experimental check up about the relative appraising index, on which 200 rainfall experiments are made, analyzing the effect of rainfall intensity to the runoff of underlying surface ; the relationship between runoff permeability and unit factor of rainfall intensity and duration ; the effect of rainfall intensity, duration, soil moisture content, and temperature to the runoff permeability ; the relationship between rainfall quantity and runoff permeability, and make mathematical imitation to the expe rimental results, to find the mutual - relationships, and make discussion about the differences between equations of fit
同時，為研究城市下墊面的產匯流特性研製了一套人工模擬降雨系統，並對相關評價指標進行了實測校驗。在此基礎上，進行了200多場降雨實驗，分析了雨強、歷時、土壤前期含水量、溫
度、降雨量、不同下墊面和不同覆
蓋度等對產匯流的影響，及各種因素對徑流系數的影響和相關性，建立了一定條件下歷時徑流系數，雨強徑流系數，流量徑流系數的函數模型。
The characteristics of biodiversity of yellow river delta are as follows : the vegetation structure is simplex and coverage is lower, which is characterized with obvious younger nature and abundant wetland ; the flora composition is simple, the plants usually could resist against salt and drought ; the xerophytes and meso - xerophytes are abundant, there are many mutual species with inner mongolia, which incarnated the biology corridor function of yellow river ; there are many animal species belong to national protected species, so the significance for biodiversity protection is great
黃河三角洲地區生物多樣性主要表現出如下特點：植被結構簡單、覆
蓋度低、生態系統年輕性特點和濕地生態系統特點明顯；植物種類少、常具有抗鹽、抗旱特性；旱生、中旱生植物以及與內蒙古共有植物種類多，充分體現了黃河的生物廊道作用；主要保護動物種類多，生物多樣性保護意義重大。
A higher surface coverage and a lower film capacitance were obtained with a subsequent modification with alkanethiol, indicating a significant improvement in the quality of the films
用烷基硫醇進一步修飾席夫堿自組裝膜后，表面覆
蓋度明顯增加，而膜電容顯著降低，說明膜質量得到了改善。
The great bustard selects the areas with abundant plant species. higher vegetative cover score. smaller proportion of bare area and taller plants to display on postfire grasslands ; the important factors that influence the great bustard to selection display fields are the proportion of hay, stipa baicalensis density and the thickness of hay on unburing grassland
在火燒地，大鴇會選擇植物種類數較多、
蓋度較大、裸地比例較小及植株相對較高處進行求偶炫耀；在非火燒地，枯草比例、貝加爾針茅密
度及枯草厚
度是影響其求偶場選擇的重要因素。
V ) occupying space and covering ground should be served as the main strategy in early stage of vegetation restoration, which would enable the community coverage to rehabilitate rapidly. in mid - stage, due to the change of light environment and the species substitution, component adjustment should be chose as the main strategy
5 ）植被恢復的策略是早期階段以搶占空間、覆
蓋地面的對策為主，群落
蓋度恢復很快;中期階段，林內光照環境改變，物種替代，恢復對策以物種組成成分的調整為主;後期則是生物量積累與組成結構調整並重。
In the meanwhile, the best community that was picked out from natural deciduous broad - leaved forest was taken as contrast. and the hight, dominance, soil fertility, coverage, composition and biomass of the community were used as community characteristics parameters to comprehensively evaluate the restored degree of communities at different restoration stages
同時，在天然闊葉落葉林中選取一個最佳群落作為參照，運用群落高度、顯著度、土壤肥力、蓋度、組成結構和生物量6個指標為群落特徵參數，對各個階段群落恢復的程度進行了綜合的評價。
