This paper is the result of the natural resources survey engineering.

Objective Based on the spatial data of land use, Digital Elevation Model (DEM), vegetation and meteorological data we quantitatively analyzed temporal and spatial variation of natural resources and their effects on regional ecological environment in Northeast China from 1990 to 2018.

Methods In accordance with the distribution regularity of nature, geography and natural resource in Northeast China, the study area was divided into 7 second- class zones and 14 third- class zones in comprehensive regionalization of natural resources by combining quantitative calculation and qualitative analysis. This paper analyzed temporal and spatial dynamic characteristics of natural resources and their ecological environmental effects in recent 30 years.

Results The results showed as follows: (1) The main changes in the study area were the conversion of forest and grassland to cultivated land and water body and wetland from 1990 to 2018. Meanwhile, large areas of cultivated land was developed into built- up areas. In addition, the transformation of grassland to desertification was also prominent. The above phenomena were closely related to the local policy of revitalizing the old industrial base in Northeast China and strengthening agriculture and benefiting farmers policy, etc. (2)The overall ecological environment quality of the study area showed a declining trend, especially in I1, I5, I6 and I7 subregions(I1 Sanjiang plain temperate arable subregion, I5 Mountain temperate forest subregion of Lesser Khingan Mountains, I6 Piedmont plain temperate arable subregion and I7 Songliao plain temperate grass-tillage subregion. (3) The main reasons for the deterioration of ecological environment quality were that forest land and grassland were reclaimed as cultivated land and that grassland was turning to desertification.

Conclusions In the past 30 years, large areas of forest and grassland in the study area have been transformed into cultivated land and water body and wetland, cultivated land has been developed into built- up areas and grassland desertification has intensified. There was a significant decreasing trend of ecological environment quality in the I1, I5, I6 and I7 subregions. The conversion of forest and grassland to cultivated land and grassland desertification mainly contributed to this phenomenon.