scholarly journals Temporal and spatial variation of NPP and its response to climatic factors in main river valleys on the southern slope of Qilian Mountains

2019 ◽  
Vol 131 ◽  
pp. 01044
Author(s):  
Rong-rong Yang ◽  
Guang-chao Cao ◽  
Sheng-kui Cao ◽  
Yao Lan ◽  
Zhuo Zhang ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Climatic Factors ◽  
Growing Season ◽  
Qilian Mountains ◽  
River Valley ◽  
Distribution Characteristics ◽  
Southern Slope ◽  
Qilian Mountain ◽  
Main River ◽  
River Valleys

Based on the NPP products of MODIS data, the spatial and temporal distribution characteristics of grassland NPP and its response to climatic factors in the vegetation growing season of the main river valleys in the southern slope of Qilian Mountains from 2000 to 2016 were carried out by correlation analysis and spatial interpolation. The research further provides a scientific basis for the quality evaluation of grassland ecosystems on the southern slope of Qilian Mountain and the rational use of grassland resources along the river. The results show that: (1) With the increasing distance of buffers on both sides of the river, the NPP of grassland in each year shows the characteristics of “single-peak” distribution, which is increased first and then decreased; (2) the NPP of grassland in the main river valley of the southern slope of Qilian Mountain The spatial distribution characteristics show a trend of increasing from northwest to southeast. (3) The spatial distribution of NPP and air temperature in the main river valleys of the southern slope of Qilian Mountains is gradually increasing from northwest to southeast, but the spatial distribution correlation coefficient of NPP and precipitation in the river valley grassland of vegetation growing season basically shows a trendof decreasing from northwest to southeast.

Ancient Settlements in the Main River Valley, Chukchi Peninsula

1962 ◽  
Vol 27 (4) ◽  
pp. 546-556
Author(s):  
A. P. Okladnikov ◽  
I. A. Nekrasov
Keyword(s):  
Northeast Asia ◽  
Size Variation ◽  
River Valley ◽  
The Arctic ◽  
Chukchi Peninsula ◽  
Late Neolithic ◽  
Chipped Stone ◽  
Neolithic Culture ◽  
Main River ◽  
River Valleys

AbstractA newly discovered late Neolithic culture of riverine hunters and fishermen becomes the third major culture known in the Chukchi-Koryak region of Northeast Asia. The arctic maritime hunters ancestral to the Eskimo have long been known, and recently evidence for an inland group of hunters in the northern reindeer and fish areas has been encountered. The Neolithic hunters and fishers lived in temporary, probably winter camps of semisubterranean houses near the game-rich mouths of tributaries on the well-drained gravel floodplains of the river valleys of the Anadyr-Penzhina lowlands. Collections from Vakernaia 1 and 2 in the Main River valley are described. Chipped stone artifacts with pressure retouch include some obsidian knives, and trapezoidal and semilunar knives made on pebble flakes. There are grinder picks, polished slate knives of ulo type, and adzes including a form comparable to the splitting adz of the Chugach sequence in southern Alaska. Picks or mattocks were made of walrus tusk and antler. The bulk of the collection consists of pottery. Hemispherical vessels of great size variation are plain, textile-impressed, and stamped. Although house type, the walrus tusk, and the ulo knives suggest some connection with the Bering Sea hunting cultures, the basic traits appear to be of more local origin.

scholarly journals Morphometry Characteristics of Riverbed Sediment Grains as Basic Indicator Management of River Valley Environment (Case Study of Bogowonto River, Central Java)

2016 ◽  
Vol 29 (2) ◽  
pp. 175
Author(s):  
Suprapto Dibyosaputro
Keyword(s):  
Sampling Site ◽  
River Valley ◽  
Central Java ◽  
Main River ◽  
Main River Channel ◽  
Riverbed Sediment ◽  
Preparation Phase ◽  
The Stability ◽  
River Valleys

This research aims to propose the usage of riverbed sediment grains roundness/flatness as basic indicator of river valley management. It is based on the evaluation of anomalous morphometry condition of sediment grains and valley condition along the river as one indicator of the stability of the riverbank of the river valley. This stability express the physical condition of the river valleys. In this paper, we provide methodological explanation as well as a case study in Bogowonto River. Analysis of the morphometry of sediment grain on riverbed from upstream to downstream as well as the relationship between the distance of the upstream and morphometry of sediment grains along Bogowonto River were conducted. Finally, we evaluated the anomalous condition as indicator of different environmental condition of the riverbank. We conducted three stages survey processes: preparation, fieldwork, and post-fieldwork. The preparation phase includes site selection, depiction of the main river channel of Bogowonto River, and the determination of the sample location. The distance between each sampling site was 5 km along Bogowonto River. The results show that there is anomalous morphometry of sediment grains found in the study area. The reason is that the channel of the segment of the river flowing over rocky riverbed of breccia along the 7.5 km, with hard and sharps edge grained of rock particles. This is accompanied by landslide the occurrence in the upper segment of the river. This is why the value of roundness and flatness indexes are changed significantly become lower value than the previous segment. This condition can be implemented to be used as indicator to basic management of landslide along a certain segment which indicated by the changing in roundness and flatness index values of the sediment grains. 

Distribution characteristics of soil carbon during forage greening in different alpine grasslands of Eastern Qilian Mountains

2009 ◽  
Vol 17 (6) ◽  
pp. 1111-1116
Author(s):  
Cheng-De YANG ◽  
Xiu-Rong CHEN ◽  
Rui-Jun LONG ◽  
Li Xue ◽  
Zhen-Fen ZHANG
Keyword(s):  
Soil Carbon ◽  
Qilian Mountains ◽  
Distribution Characteristics ◽  
Alpine Grasslands

scholarly journals A Stepwise GIS Approach for the Delineation of River Valley Bottom within Drainage Basins Using a Cost Distance Accumulation Analysis

Water ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 827
Author(s):  
Gasper L. Sechu ◽  
Bertel Nilsson ◽  
Bo V. Iversen ◽  
Mette B. Greve ◽  
Christen D. Børgesen ◽  
...  
Keyword(s):  
Spatial Data ◽  
Nutrient Loading ◽  
Drainage Basin ◽  
River Valley ◽  
Management Tool ◽  
Drainage Basins ◽  
Valley Bottom ◽  
Management Actions ◽  
Cost Distance ◽  
River Valleys

River valley bottoms have hydrological, geomorphological, and ecological importance and are buffers for protecting the river from upland nutrient loading coming from agriculture and other sources. They are relatively flat, low-lying areas of the terrain that are adjacent to the river and bound by increasing slopes at the transition to the uplands. These areas have under natural conditions, a groundwater table close to the soil surface. The objective of this paper is to present a stepwise GIS approach for the delineation of river valley bottom within drainage basins and use it to perform a national delineation. We developed a tool that applies a concept called cost distance accumulation with spatial data inputs consisting a river network and slope derived from a digital elevation model. We then used wetlands adjacent to rivers as a guide finding the river valley bottom boundary from the cost distance accumulation. We present results from our tool for the whole country of Denmark carrying out a validation within three selected areas. The results reveal that the tool visually performs well and delineates both confined and unconfined river valleys within the same drainage basin. We use the most common forms of wetlands (meadow and marsh) in Denmark’s river valleys known as Groundwater Dependent Ecosystems (GDE) to validate our river valley bottom delineated areas. Our delineation picks about half to two-thirds of these GDE. However, we expected this since farmers have reclaimed Denmark’s low-lying areas during the last 200 years before the first map of GDE was created. Our tool can be used as a management tool, since it can delineate an area that has been the focus of management actions to protect waterways from upland nutrient pollution.

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