New Zealand Journal of Ecology (1997) 21(2): 129-140 ©New Zealand Ecological Society these conceptual extremes should be seen as being endpoints of a range of possible situations, and not as discrete alternatives. It is therefore unlikely that an observed field situation would be completely described by any one of the models alone. More recently developed models use the conceptual extremes as c...

Cyanobacterial diversity in soil crusts has been extensively studied in arid lands of temperate regions, particularly semi-arid steppes and warm deserts. Nevertheless, Arctic soil crusts have received far less attention than their temperate counterparts. Here, we describe the cyanobacterial communities from various types of soil crusts from Svalbard, High Arctic. Four soil crusts at different d...

100-150 words) Remote sensing methods for locating and monitoring temporary ponds over large areas in arid lands were tested on a study site in Northern Senegal. Three main results are presented, validated with field data and intended to highlight different spectral, spatial and temporal characteristics of the methods: 1) Among several water indices tested, two Middle InfraRed-based indices (MN...

100-150 words) Remote sensing methods for locating and monitoring temporary ponds over large areas in arid lands were tested on a study site in Northern Senegal. Three main results are presented, validated with field data and intended to highlight different spectral, spatial and temporal characteristics of the methods: 1) Among several water indices tested, two Middle InfraRed-based indices (MN...

Opal phytoliths, as silicon dioxide inclusions, are abundant in different parts of a plant. It is known that grasses the most representative this respect. The research removed from 25 common grass species arid and semiarid lands Junggar Basin adjacent areas, has been undertaken. visual estimation diversity variability silica cells identification their morphological types (patterns) were also ai...