All chapters:

Introduction

Climate

Waters and water management

Ecosystems and ecoregions

Species diversity and use of biological resources

Nature conservation: econet and protected areas

Countries & cultures

Economy

Land use

International policy

Ecosystems and ecoregions

The basin supports diverse forest habitat like rich Korean pine (Pinus koraiensis) mixed broadleaf temperate forests of the Sikhote-Alin and Small Hinggan ranges, the depauperate Larch (Larix gmelini) boreal forests and moraines on permafrost in the north, and alpine tundra in the mountains of Stanovoy and other mountain ranges. Plateaus and lowlands exhibit equally diverse ranges of grassland and wetland habitats from the grassland prairies of the Khanka-Xingkai Lake lowlands to forest-meadows of the Middle Amur-Heilong, to forest-steppe and dry steppe landscapes in the western half of the region.
Out of 15 large terrestrial ecoregions recognized in the basin eleven are dissected by national borders. Four ecoregions are recognized as global priority for nature conservation.

High levels of landscape diversity in the Amur-Heilong River basin are largely the result of historic and spatial variability in conditions across the region. Altitudinal variation and horizontal zoning also help form numerous biogeographic regions. Situated on the eastern rim of Eurasia and abutting the Pacific Ocean, the basin is subject to the combined effects of monsoon climate conditions, oceanic currents, and mountains that direct air circulation patterns. The geology and terrain, with numerous mountain chains separated by lush valleys, present a variety of microclimate, soil, and vegetation conditions. Several geographic factors contribute to the tremendous biological diversity of the Amur-Heilong River basin:

--from north to south the basin encompasses boreal and temperate zones and extends southward into the northern tip of the subtropics;
--from west to east there is a tremendous climatic gradient from cold continental to humid monsoon climates;
--during glacial periods, most of the basin had numerous refugia not covered by ice;
--mountain ranges cross the region longitudinally, latitudinally, and diagonally, thus adding landscape-scale diversity to the basin;
--large river systems provide migration corridors that allow for the dispersal of flora and fauna and that results in a mixture of northern and southern species;
--the basin's tributaries differ hydrologically and thus form distinct aquatic habitats.

These have yielded a broad range of landscapes and unusually high levels of species diversity for temperate latitudes.

To illustrate vegetation zoning and land status around 2000 a phytogeography map, based on the work of Sochava (1969), is presented, that despite its inaccuracies, remains the best recognized classification system for the region and has been incorporated into many world-wide databases (look Map) However, this map should be compared with more current maps based studies of satellite imagery. We provide two of the most informative products currently used in world databases: one illustrates vegetation/land cover types (see Map) and the other, created by the University of Maryland, depicts vegetation cover density (see Map).

Starotsurukhaitui Meadow in Argun river floodplain
(Photo by E.Simonov)