干旱半干旱区生物结皮反射特性的研究

By studing on soil biogenic crust in arid, semi-arid Shapotou Region, there are about 40 algaes specises in the Tenggeli Desert which include blue green alga phylum, green alga phylum,diatom phylum and naked algae phylum which take 45.5% of the total species. In blue green algae 70% of them are silk blue green algae. They are Anabaena azotic Ley., Chrococcus epiphyticus Jao, Gloecapsa sp. and Lyngbya crytovaginatus Schk., Microcoleus vaginatus(Vauch) Gom., Nostoc sp., Nostoc flagelliforme Born et Flah., Phormidium tenus(Men)Gom., Scytonema javanicum(Kutz) Born et Flah , Synechocystis pevalekii Ercegovic. Green algaes are all single cell bodies and they are Chlamydomonas sp., Chlorella vulgaris Beij., Chlorococcus humicola(Naeg) Rab., Protococcus viridis Ag.; Diatom algaes are Cymbella sp., Diatom sp., Fragilaria intermedia Grun. and Navicula sp. , Hantzschia amphioxys( Ehr.) Gom. , Pinnular sp.; Naked algaes are Euglena sp. and Euglena spp. .Using the instrument of FieldSpec? Pro( 350-2500 nm) Spectraoradiometer maded in US to measure the reflection spectrum of biological crust, it shows that as the develoiopment of soil biological crust and the fixation of shifting sand dune, the reflectance features of the sand surface changing with its thickness. At the same time, after rain before rain, the reflectance features of the land surface are different. Therefore while using images of remote sensing to carry out desertification land assessment, one must emphasize on the option of image, if funds adoptedly, as far as possible to use Normalized Difference Vegetation Index( NDVI) toreduce other influence for evaluating results. .

选择在干旱半干旱区土壤表面广泛分布的生物结皮为研究对象,通过对不同类型生物结皮的槌沙煞趾头瓷涮匦缘难芯浚⒎瓷渲甘⒊⑹越溆τ玫轿佬怯跋竦慕庖牍讨校佣畲笙薅鹊叵锝崞ざ砸８惺葜兄脖惶卣餍畔⑻崛〉挠跋欤珊蛋敫珊登捎靡８惺侄窝芯科虮浠⑼恋乩?覆被变化、土地荒漠化动态以及干旱生态系统生产力提供可靠的理论支持。