scholarly journals Analysis of Basin Morphologic Characteristics and Their Influence on the Water Yield of Mountain Watersheds Upstream of the Xiongan New Area, North China

Water ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 2903
Author(s):  
Hui Yang ◽  
Jiansheng Cao

In this study, based on the DEM, we extracted the drainage networks and watersheds of the Daqing Riverwith ArcGIS, investigated the basin characteristicsandthe differences in their spatial distributions and analyzed the relations of the drainagedensity with some surface conditions and how the drainagedensityinfluenced the water yield. The results suggested a power function between the mainstream length and drainage area, showing that withthe increase in basin area, the basins became longer.The result of the power function between the relief and drainage area with negative exponent values means the relief changed more slowly with increasing basin area.The values of the circularity ratio andelongation ratio indicatethat the basin shape of the mountain watersheds in theDaqing River was narrow and predisposed to flooding during periods of heavy rainfall. The orders of the streams in the mountain watersheds ranged from five to seven.The average bifurcation ratio of those nine mountainous watersheds reveals the order of the u+1 rivers in each basin of the Daqing River was on average 4 times larger than that of order u rivers. The drainage density (Dd) was high in the north and low in the south of the Daqing River. Rainfall wasnegatively correlated with drainage density, but the correlation between them was notsignificant atthe 0.05 level. Drainages developed in places with poor vegetation cover.The drainages in the southwest, north and west developed considerably, while drainages in the east and southeast did not develop much. Yet, the available data showed the impact of the watershed area, elongation ratio and drainage density on the water yield was not significant. In contrast, there was a significant positive correlation between channel slope and the water yield modulus. The hypsometric integrals and the relation between drainage density and hypsometric integral suggest that the landform evolution of the mountain basins alongthe Daqing Riverwerein the old stage with no furtherincrease trend of drainage density in the future.

Author(s):  
Madhurjyojit Chakravartty ◽  
Nishanta Das

The present study area, occupying a major south-central part of the Jadukata river basin of the West Khasi Hills District of Meghalaya, predominantly comprises two contrasting litho-units viz., the Precambrian gneissic unit (PGU) towards the north of the study area and the Mahadek Formation constituted of sedimentary rocks (MFS) in the south. Derived areal and relief morphometric parameters have been analysed on five sub-basins two of which are in the PGU (Umlang and Umkyrtha) and the other three (Umsophew, Wah-Phodthra, and Khandow) predominantly in the MFS. The drainage density (Dd) and stream frequency (Fs) values are relatively lower for the sub-basins of PGU suggesting higher overland flow. This is substantiated by higher values of the constant of channel maintenance (C) and length of overland flow (Lg). The relief ratio (Rr) and ruggedness number (Rn) are higher for the sub-basins of MFS implying more dissection. High hypsometric integral (HI) and pseudo-hypsometric integral (PHI) suggest youthful stage and neotectonic rejuvenation with a tilt towards the west as indicated by asymmetry factor (AF) and topographic profile. Association of distinct knickpoints of longitudinal profiles with prominent lineaments indicates active fault. Preferred orientation of lower order streams in the PGU sub-basins suggests neotectonism. Deep incision by Umsophew, Wah-Phodthra, and Khandow rivers, forming V-shaped valleys through the MFS is the result of neotectonic uplift which has been further substantiated by very low valley floor-to-height ratio (Vf) at nearby locations of the confluence of these rivers with the Kynshi.


2019 ◽  
Vol 29 (3-4) ◽  
pp. 287-296
Author(s):  
Ali Chaieb ◽  
Noamen Rebai

The geomorphology of the Htab river watershed is mainly guided by the action of the E-W Kasserine fault. This activity influenced the installed hydrographic system. To see the impact of neotectonic on the Htab river watershed, four morphometric indices were applied: the elongation ratio, the hypsometric curve, the hypsometric integral, and the asymmetry factor. The processing and calculation of these indices were based on global DEMs (Digital Elevation Models). The result obtained shows an important link between the activity of the Kasserine fault, the geomorphological behavior of the Htab river watershed and the hydrographic network. Field observations confirmed well these results.


2000 ◽  
Vol 151 (12) ◽  
pp. 502-507
Author(s):  
Christian Küchli

Are there any common patterns in the transition processes from traditional and more or less sustainable forest management to exploitative use, which can regularly be observed both in central Europe and in the countries of the South (e.g. India or Indonesia)? Attempts were made with a time-space-model to typify those force fields, in which traditional sustainable forest management is undermined and is then transformed into a modern type of sustainable forest management. Although it is unlikely that the history of the North will become the future of the South, the glimpse into the northern past offers a useful starting point for the understanding of the current situation in the South, which in turn could stimulate the debate on development. For instance, the patterns which stand behind the conflicts on forest use in the Himalayas are very similar to the conflicts in the Alps. In the same way, the impact of socio-economic changes on the environment – key word ‹globalisation› – is often much the same. To recognize comparable patterns can be very valuable because it can act as a stimulant for the search of political, legal and technical solutions adapted to a specific situation. For the global community the realization of the way political-economic alliances work at the head of the ‹globalisationwave›can only signify to carry on trying to find a common language and understanding at the negotiation tables. On the lee side of the destructive breaker it is necessary to conserve and care for what survived. As it was the case in Switzerland these forest islands could once become the germination points for the genesis of a cultural landscape, where close-to-nature managed forests will constitute an essential element.


2019 ◽  
pp. 3-20
Author(s):  
V.N. Leksin

The impact on healthcare organization on the territory of Russian Arctic of unique natural and climatic, demographic, ethnic, settlement and professional factors of influencing the health of population, constantly or temporarily living on this territory is studied. The necessity is substantiated of various forms and resource provision with healthcare services such real and potential patients of Arctic medical institutions, as representatives of indigenous small peoples of the North, workers of mining and metallurgical industry, military personnel, sailors and shift workers. In this connection a correction of a number of All-Russian normative acts is proposed.


2018 ◽  
Vol 68 (suppl 1) ◽  
pp. bjgp18X696929
Author(s):  
Jill Mitchell

BackgroundThere is an emerging debate that general practice in its current format is out-dated and there is a requirement to move to a federated model of provision where groups of Practices come together. The emergence of federations has developed over the past 5 years but the factors that influence how federations develop and the impact of this new model is an under researched area.AimThe study explored the rationale around why a group of independent GP practices opted to pursue an alternative business venture and the benefits that this strategy offered.MethodA single organisational case study of a federation in the North of England was conducted between 2011–2016. Mixed methods data collection included individual and group semi-structured interviews and quantitative surveys.ResultsFederations promote collaborative working, relying on strategic coherence of multiple individual GP practices through a shared vision and common purpose. Findings revealed many complexities in implementing a common strategy across multiple independent businesses. The ability of the federation to gain legitimacy was two dimensional – externally and internally. The venture had mixed successes, but their approach to quality improvement proved innovative and demonstrated outcomes on a population basis. The study identified significant pressures that practices were experiencing and the need to seek alternative ways of working but there was no shared vision or inclination to relinquish individual practice autonomy.ConclusionOrganisational development support is critical to reform General Practice. Whether central funding through the GP Five Year Forward View will achieve the scale of change required is yet to be evidenced.


2019 ◽  
pp. 4-15
Author(s):  
I. A. Korgun ◽  
G. D. Toloraya

The presented study analyzes the opportunities for North Korea to capitalize on its competitive advantages in foreign trade in the context of sanctions.Aim. The study aims to identify mechanisms that allow North Korea to engage in foreign trade in circumvention of UN sanctions and to analyze their impact on the national economy.Tasks. The authors analyze the structure of North Korea’s national economy, its initial competitive advantage, identify the specific features of North Korea’s foreign trade in the context of sanctions, and determine the consequences of illicit trade in circumvention of sanctions for the national economy.Methods. This study uses an interdisciplinary approach that combines the classical theory of competitive advantage with the concept of rent seeking, with the concept of rent seeking and analysis of trade flows.Results. The study shows that, despite the restrictions imposed by sanctions, North Korea strives to make the most of its advantages, such as resource availability and cheap labor, in global trade. The country builds its own export-import chains in circumvention of sanctions. These chains are rather mobile, flexible, and controlled by the elite. As a result, benefits from trade that could be evenly distributed among the population are concentrated in the hands of a narrow segment of society. ‘Rent seeking’ makes it possible to formulate the negative consequences of these processes for the North Korean economy and the international community.Conclusions. Solving the North Korean issue requires an economic transformation in the country through the replacement of restrictive sanctions with more constructive ones. The exclusion of North Korea from open global trade leads to the country’s marginalization and impairs the transparency of international commodity flows.


1995 ◽  
Vol 31 (10) ◽  
pp. 61-71 ◽  
Author(s):  
M. Enell

During the last 20 years there has been an interesting development of the Nordic fish farming, with regard to the feeding and farming technology and to the increase in production quantities. During the period 1974-1994 the production increased from 15,800 to about 250,000 tonnes/year. In 1974 the major part of the production was in Denmark, and in 1994 the major part was in Norway. The nutrient impact of fish farming on surrounding sea areas is mainly a function of the feed coefficient, the feed composition and metabolic processes in the fish. The comprehensive development of the feed composition and the feeding technology has resulted in reduced load of unmetabolized nutrients from fish farms, calculated per tonne fish produced. In 1974 the mean Nordic feed coefficient was 2.08 and in 1994 the coefficient was 1.25. Feed coefficients of 1.0-1.1 are now reported for Danish and Norwegian freshwater and marine fish farms. The nitrogen (N) and phosphorus (P) content of the feed has decreased, in addition the quality of the nutrient substances in the feed has changed, especially for N. The N content has decreased from 7.8 to 6.8% during the period 1974-1994 and the content of P has decreased from 1.7 to 0.7% during the same period. This development of the feed coefficient and the feed composition has resulted in a present load from a typical Nordic fish farm of 55 kg N and 4.8 kg P/t fish produced. The figures for 1974 were 132 kg N and 31 kg P/t fish produced. The Nordic fish farming production in 1994 resulted in a load of about 13,750 t N and about 1,200 t P on the actual recipients. The load from the Swedish, Finnish and Danish fish farming operations, with the Baltic Sea and the Skagerrak as the recipients, is negligible in comparison with other pollution sources. The quantities of N and P from the fish farming are equal to 0.5% of the atmospheric deposition on the sea surface and 3% of the atmospheric P load. Norwegian, Icelandic and the Faroe Islands fish farming operations are using the North Sea and the Norwegian Sea as the recipients. However, the nutrient load from single fish farms in certain coastal and inland water bodies can be significant and must be considered in the impact assessment together with other sources.


Sign in / Sign up

Export Citation Format

Share Document