|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Comparison of water quality in two catchments with different forest types in the headwater region of the Hun River, Northeast China显示文摘In the headwater catchments of the Hun River,Northeast China, secondary forests(SF) have been replaced by plantations since the 1960 s. Concern has been growing over this loss and the decline in water quality caused by the plantations. To test the effects of plantations on water quality, we selected two separate catchments covered by SF and Pinus koraiensis plantations(KP) to monitor physical and chemical properties of various hydrological variables including throughfall, stemflow,through-litterfall and runoff(flowing out of outlets of the catchments). The physical properties of water declined after water flowed through the two catchments as compared with rainwater. The pH of runoff in both catchments also dramatically decreased. The concentrations of Cl^-, NO_3^- and NH_4^+ in the runoff from the two catchments were similar(concentrations of Cl-and NH_4^+ in both catchments were similar to those in rainwater). Total P concentration in runoff of the SF catchment was higher than that of the KP catchment(P concentrations in both catchments were also higher than in rainwater) because P concentrations in litter and soil of the SF catchment were higher than those in the KP catchment. In summary, the rainwater became acidic in both catchments, but the responses of most water quality variables were similar in the two catchments, suggesting that appropriate ratios of KP in SF are feasible for secondary forest recovery and for preserving water quality(KP did not cause a decline in quality) in the headstream regions in Northeast of China. | Jiao-jun Zhu Li-zhong Yu Tian-le Xu Xiaohua Wei Kai Yang | 2019 | Journal of Forestry Research2019，30，2： | 4 |
| 2 | Assessing sediment connectivity and its spatial response on land use using two flow direction algorithms in the catchment on the Chinese Loess Plateau显示文摘Severe soil and water loss have led to widespread land degradation on the Loess Plateau in China.Exploring the relationship between land use and sediment connectivity can be beneficial to control soil erosion.In this study,three catchments in the Yanhe River Basin on the Loess Plateau were selected to analyse the relationship between land use and sediment connectivity using grey correlation method.Index of connectivity(IC)was employed to quantify sediment connectivity,including two flow direction algorithms(D8 and D-infinity)and two final targets of sediment transport(outlet and main channel of catchment).Then,11 landscape metrics were used to evaluate the land use spatial patterns of catchments.By comparing the IC value ranges,histograms and classes,and their relationship with remote sensing images of the two flow direction algorithms,we find that the D8 algorithm is more suitable for this study area.The results showed that the three catchments are characterized by high sediment connectivity in the grassland and forest close to the channel.In addition,the roads and bare land close to the channel also have high or medium sediment connectivity.Grey correlation analysis showed that landscape division index(DIVISION),fractal dimension index(FRACMN),aggregation index(AI),total class area,patch cohesion index(COHESION),and largest patch index(LPI)indices were the main factors that affect sediment connectivity at the class scale.At the landscape scale,the landscape shape index(LSI),Shannon’s diversity index(SHDI),and gully density have an essential effect on sediment connectivity.This condition provides a way to control the sediment connectivity in the watershed by transforming land use type or changing its spatial pattern,but specific adjustment measures have to be further explored. | YAN Xi-qin JIAO Ju-ying TANG Bing-zhe LIANG Yue WANG Zhi-jie | 2022 | Journal of Mountain Science2022，19，4： | 1 |
| 3 | Zonal aspects of the influence of forest cover change on runoff in northern river basins of Central Siberia显示文摘Background:Assessment of the reasons for the ambiguous influence of forests on the structure of the water balance is the subject of heated debate among forest hydrologists.Influencing the components of total evaporation,forest vegetation makes a significant contribution to the process of runoff formation,but this process has specific features in different geographical zones.The issues of the influence of forest vegetation on river runoff in the zonal aspect have not been sufficiently studied.Results:Based on the analysis of the dependence of river runoff on forest cover,using the example of nine catchments located in the forest-tundra,northern and middle taiga of Northern Eurasia,it is shown that the share of forest cover in the total catchment area(percentage of forest cover,FCP)has different effects on runoff formation.Numerical experiments with the developed empirical models have shown that an increase in forest cover in the catchment area in northern latitudes contributes to an increase in runoff,while in the southern direction(in the middle taiga)extensive woody cover of catchments“works”to reduce runoff.The effectiveness of geographical zonality in regards to the influence of forests on runoff is more pronounced in the forest-tundra zone than in the zones of northern and middle taiga.Conclusion:The study of this problem allowed us to analyze various aspects of the hydrological role of forests,and to show that forest ecosystems,depending on environmental conditions and the spatial distribution of forest cover,can transform water regimes in different ways.Despite the fact that the process of river runoff formation is controlled by many factors,such as temperature conditions,precipitation regime,geomorphology and the presence of permafrost,the models obtained allow us to reveal general trends in the dependence of the annual river runoff on the percentage of forest cover,at the level of catchments.The results obtained are consistent with the concept of geographic determinism,which explains the contradictions that exist in assessing the hydrological role of forests in various geographical and climatic conditions.The results of the study may serve as the basis for regulation of the forest cover of northern Eurasian river basins in order to obtain the desired hydrological effect depending on environmental and economic conditions. | A.Onuchin Т.Burenina А.Shvidenko D.Prysov A.Musokhranova | 2021 | Forest Ecosystems2021，8，3： | 0 |
| 4 | Episode Studies on Catchments Chemistry at Tie Shan Ping,Chongqing显示文摘The Tie Shan Ping(TSP) catchments are acidified due to acid deposition.The highest concentrations of SO2-4,NO-3,Ca2+,Mg2+ Al3+ and H+ occur in soil water and the maximum of molar ratio Ali/(Ca+Mg) during the Episode Studies is 1.27 in the bottom soil water in May 2003.Fuzzy Cluster Analysis for compartmental water chemistry in catchments shows stream water(SW) originates from the soil water generally.During event rain there may be 'pulse' of high concentration of chemical species in the stream.Total organic carbon,organic bound aluminum,total phosphorus,total nitrogen,NO-3 in SW are controlled by quick(high) flow.SW at new dam at TSP is from quick flow largely,including overland flow during wet period.Al3+,SO2-4 and H+ in SW are controlled by base flow during dry period and SW at old dam at TSP is from the base flow,largely.There are 'alkaline pulse' and 'acid pulse' in stream water during the event rain.The former may be caused by overland flow over the litterfall and topsoil horizons,and the latter by 'piston flow' from soil water in deeper soil horizon largely. | Zhao Dawei(Chongqing Institute of Environmental Science and Monitoring,Chongqing 400020,China) | 2007 | 工程科学(英文版)2007，5，3： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员