Assessment of the eco-environmental quality in the Nanweng River Nature Reserve, Northeast China by remote sensing.

Scientific and rapid assessment of the ecological environment quality based on remote sensing can provide basis for regional protection, management and planning. In this study, using Landsat TM/OLI/TIRS in 1990, 2000 and 2015 as data sources, four indices including the wetness component of the tasseled cap transformation (WET), normalized difference vegetation index (NDVI), normalized difference built-up and soil index (NDSI), and land surface temperature (LST) were derived, with the weights being determined by principal components analysis (PCA). Remote sensing ecological index (RSEI) was used to evaluate the eco-environmental quality of Nanweng River Nature Reserve from 1990 to 2015.

[Dynamics of habitat suitability for waterfowls from 1990 to 2015 in the ecological function zone of Sanjiang Plain, Northeast China].

As a wetland of international importance, the ecological function zone of the Sanjiang Plain (EFZSP) plays an important role in maintaining waterfowl habitat. With the increasing disturbance of human beings, land use and climate changes, habitat suitability for waterfowls (HSW) has drawn greater attention of ecologists. In this study, Landsat TM/ETM+/OLI and HJ-1B images in 1990, 2000, 2010 and 2015 were used to obtain land cover classification by object-based image analysis, and the entropy and analytic hierarchy process methods were adopted to determine the factors and their weights, the factors selected in this study included water condition (lake and river density), disturbance factor (residence and road density), shelter condition (land cover type and slope), and food abundance (NDVI).

[Wetlands of priority restoration in Northeast China based on spatial analysis].

By using GIS/RS technology, and from the aspects of landscape structure, river- and road densities, wetness index, geomorphology, and cultivated land productivity, a spatial analysis was made on the potentiality of wetland restoration in Northeast China, with the regions of priority and secondary priority restoration wetlands determined. Then, by using the coordinated development index of crop production and wetland as well as the landscape indices, the wetland restoration effect was verified. In Northeast China, the wetland area of priority restoration was 1.

[Spatial and temporal variability of soil C/N ratio in Songnen Plain maize belt].

The C/N ratio of soils is a sensitive indicator of soil quality, and an indicator for assessing carbon and nitrogen nutrition balance of soils. Its variation is significant in reflecting the carbon and nitrogen cycling of soils. Based on field investigation, sample collection and analysis, and application of geostatistics and GIS technology, spatial and temporal variation of C/N ratio was analyzed and studied from 1980 to 2005 in Songnen Plain maize belt.

[Spatial characteristics of soil organic carbon and nitrogen storages in Songnen Plain maize belt].

By using the data of 382 typical soil profiles from the second soil survey at national and county levels, and in combining with 1:500000 digital soil maps, a spatial database of soil profiles was established. Based on this, the one meter depth soil organic carbon and nitrogen storage in Songnen Plain maize belt of China was estimated, with the spatial characteristics of the soil organic carbon and nitrogen densities as well as the relationships between the soil organic carbon and nitrogen densities and the soil types and land use types analyzed. The soil organic carbon and nitrogen storage in the maize belt was (163.