DISTRIBUTION OF ODONATA （INSECTA） IN VARIOUS ECOSYSTEMS IN NORTHERN PENINSULAR MALAYSIA

Odonata larvae and adults were collected from fourteen sites of various habitats including rivers, rice fields, mountain streams, freshwater and peat swamps, oil palm, sugarcane and rubber plantations and lake. Out of 51 species recorded, Libellulidae made up the most dominant of 10 families followed by Gomphidae and Coenagrionidae. Other families were less common. Riverine and stream ecosystems were the most diverse, both with six families and 19 and 13 species respectively. In the rice fields, Libellulidae and Coenagrionidae were represented by 17 and seven species respectively. The poorest fauna of Odonata was recorded from a lake system. A few of libellulids were found to be pollution tolerant and widespread in distribution. Many odonate species were restricted to preferred habitats or water parameter gradients that could be used as bioindicators of respective habitats or parameters.     

Hydroclimatological changes in the Bagmati River Basin, Nepal

Study on hydroclimatological changes in the mountainous river basins has attracted great interest in recent years. Changes in temperature, precipitation and river discharge pattern could be considered as indicators of hydroclimatological changes of the river basins. In this study, the temperatures （maximum and minimum）, precipitation, and discharge data from 1980 to 2009 were used to detect the hydroclimatological changes in the Bagmati River Basin, Nepal. Simple linear regression and Mann-Kendall test statistic were used to examine the significant trend of temperature, precipitation, and discharge. Increasing trend of temperature was found in all seasons, although the change rate was different in different seasons for both minimum and maximum temperatures. However, stronger warming trend was found in maximum temperature in comparison to the minimum in the whole basin. Both precipitation and discharge trend were increasing in the pre-monsoon season, but decreasing in the post-monsoon season. The significant trend of precipitation could not be observed in winter, although discharge trend was decreasing. Furthermore, the intensity of peak discharge was increasing, though there was not an obvious change in the intensity of maximum precipitation events. It is expected that all these changes have effects on agriculture, hydropower plant, and natural biodiversity in the mountainous river basin of Nepal.     

1960-2007年中国地表潜在蒸散发敏感性的时空变化(英文)

Potential evapotranspiration (E0), as an estimate of the evaporative demand of the atmosphere, has been widely studied in the fields of irrigation management, crop water demand and predictions in ungauged basins (PUBs). Analysis of the sensitivity of E0 to meteorological factors is a basic research on the impact of climate change on water resources, and also is important to the optimal allocation of agricultural water resources. This paper dealt with sensitivity of E0 over China, which was divided into ten drainage systems, including Songhua River basin, Liaohe River basin, Haihe River basin, Yellow River basin, Yangtze River basin, Pearl River basin, Huaihe River drainage system, Southeast river drainage system, Northwest river drainage system and Southwest river drainage system. In addition, the calculation method of global radiation in Penman-Monteith formula was improved by optimization, and the sensitivities of Penman-Monteith potential evapotranspiration to the daily maximum temperature (STmax), daily minimum temperature (STmin), wind speed (SU2), global radiation (SRs) and vapor pressure (SVP) were calculated and analyzed based on the long-term meteorological data from 653 meteorological stations in China during the period 1960-2007. Results show that: (1) the correlation coefficient between E0 and pan evaporation increased from 0.61 to 0.75. E0 had the decline trends in eight of ten drainage systems in China, which indicates that "pan evaporation paradox" commonly exists in China from 1960 to 2007. (2) Spatially, Tmax was the most sensitive factor in Haihe River basin, Yellow River basin, Huaihe River drainage system, Yangtze River basin, Pearl River basin and Southeast river drainage system, and VP was the most sensitive factor in Songhua River Basin, Liaohe River basin, Northwest river drainage system while Rs was the most sensitive factor in Southwest river drainage system. For the nation-wide average, the most sensitive factor was VP, followed by Tmax, Rs, U2 and Tmin. In addition, the changes in sensitivity coefficients had a certain correlation with elevation. (3) Temporally, the maximum values of STmax and SRs occurred in July, while the maximum values of STmin, SVP and SU2 occurred in January. Moreover, trend analysis indicates that STmax had decline trends, while STmin, SU2, SRs and SVP had increasing trends.     

Seasonal Changes in Mayfly Communities and Abundance in Relation to Water Physicochemistry in Two Rivers at Different Elevations in Northern Peninsular Malaysia

A field study was performed at rivers in Gunung Jerai forest reserve(Kedah,Malaysia) to assess seasonal changes in mayfly community structure and abundance in relation to altitude and water physicochemistry.Rivers at lower(Batu Hampar River) and higher(Teroi River) elevations were visited through dry and wet seasons in September 2007 to August 2008.Monthly visits were made to 20 sites on each river,and water and aquatic insects were sampled using D-pond aquatic nets.Water was warmer,more acid,and more turbid in Teroi River during wet season.Ammonia was the only nutrient exhibiting significant seasonal variations(greater during wet season).Chemical oxygen demand content was higher in Teroi River where biochemical oxygen demand content was low during wet season.Species richness was higher in Batu Hampar River,but displayed seasonal variations only in Teroi River.Among the eight families encountered,Baetidae was the commonest.Baetid abundance was usually high during wet season,and those belonging to the dominant genus(Baetis) were more abundant in Teroi River.Heptageniidae was the second commonest family;its predominant genus,Thalerospyrus was more abundant in Teroi River during dry season.Caenidae,Leptophlebiidae and Oligoneuriidae were only found in Batu Hampar River where their abundances peaked during dry season,i.e.,Habrophlebiodes sp.and Isonychia sp.Ephemerellidae and Teloganodidae occurred only in Teroi River,with the first found only during dry season.Mayflies were recorded under very distinct physicochemical conditions,illustrating their potential usefulness for assessing water quality.Caenids,leptophlebids,oligoneurids ephemerellids and teloganodids seem to be particularly sensitive to temperature,acidity,turbidity,chemical oxygen demand and biochemical oxygen demand,parameters that varied with river altitude.     

地貌特征对约旦南部阿尔阿加河(WadiAl-Arja)流域产沙影响分析(英文)

This study addresses the morphometric variables that determine the sediment yield in Wadi Al-Arja through the analysis of the impact of different morphometric characteristics along the course of the valley on its sediment yield, as well as the analysis of spatial and formal dimensions and morphologies of the basin and its relationship to the sediment yield. The study also addresses the size of variation in the volume of sediment yield of the river tributaries that make up the water network of the valley under the differences of its morphometric and hydrological characteristics. The study found several results, most notably: The classification of Wadi Al-Arja basin according to the hypsometric integral value(72.1%) within an uneven topography, which increases the force of the erosive activity and the size of the sediment yield if the basin was exposed to moist climatic periods. The study also showed the presence of convergence in the intra-spaces between the river tributaries in the water network. This increases the volume of water flows when these tributaries meet with each other and thus increasing their erosive ability and sediment yield. The study also showed the presence of marked variation in the sediment yield of the river tributaries depending on the differences in its morphometric characteristics. The results of the step-wise regression analysis confirmed the importance of the morphometric and hydrological variables, and plant coverage in interpreting the variation in the size of the sediment yield of the river tributaries of different stream order in Wadi Al-Arja basin, where these variables interpreted 43% of the total variation, with statistical significance less than 0.05.     

基于小波分析的江河源区汛期和枯水期径流特征(英文)

By decomposing and reconstructing the runoff information from 1965 to 2007 of the hydrologic stations of Tuotuo River and Zhimenda in the source region of the Yangtze River, and Jimai and Tangnaihai in the source region of the Yellow River with db3 wavelet, runoff of different hydrologic stations tends to be declining in the seasons of spring flood, summer flood and dry ones except for that in Tuotuo River. The declining flood/dry seasons series was summer > spring > dry; while runoff of Tuotuo River was always increasing in different stages from 1965 to 2007 with a higher increase rate in summer flood seasons than that in spring ones. Complex Morlet wavelet was selected to detect runoff periodicity of the four hydrologic stations mentioned above. Over all seasons the periodicity was 11-12 years in the source region of the Yellow River. For the source region of the Yangtze River the periodicity was 4-6 years in the spring flood seasons and 13-14 years in the summer flood seasons. The differences of variations of flow periodicity between the upper catchment areas of the Yellow River and the Yangtze River and between seasons were considered in relation to glacial melt and annual snowfall and rainfall as providers of water for runoff.     

塔里木河中游植物群落的数量分类与分析

Plant communities were sampled in the lower reaches of the Tarim River,Xinjiang,The results showed that there are 23 species belonging to 21 genera in 11 families,most of which have low occurrence frequency in quadrats.The most common species is Tamarix ramosissima,which occurred in 17 sites accounting for 89.47% of the total 19 sites,Quantitative classification (TWINSPAN) and ordination(CCA) methods were used to study the distribution Patterns of 23 plant species in 19 sites in this valley.TWINSPAN results showed that the plant communities in the middle reaches of the Tarim River could be divided into 3 groups and the sampling sites could be diveded into 7 types in 3 groups .CCA results were consistent with TWINSPAN results ,and showed species distribution patterns correlated with major environmental variables of groundwater level and soil moisture.     

黑河流域NDVI与环境因子的空间关联性（英文）

The Heihe River Basin is located in the arid and semi-arid regions of Northwest China.Here,the terrestrial ecosystem is vulnerable,making it necessary to identify the factors that could affect the ecosystem.In this study,MODIS-NDVI data with a 250-m resolution were used as a proxy for the terrestrial ecosystem.By combining these with environmental factors,we were able to explore the spatial features of NDVI and identify the factors influencing the NDVI distribution in the Heihe River Basin during the period of 2000–2016.A geographical detector(Geodetector) was employed to examine the spatial heterogeneity of the NDVI and to explore the factors that could potentially influence the NDVI distribution.The results indicate that:(1) the NDVI in the Heihe River Basin appeared high in the southeast while being low in the north,showing spatial heterogeneity with a q-statistic of 0.38.The spatial trend of the vegetation in the three sub-basins generally increased in the growing seasons from 2000 to 2016;(2) The results obtained by the Geodetector(as denoted by the q-statistic as well as the degree of spatial association between the NDVI and environmental factors) showed spatial heterogeneity in the associations between the NDVI and the environmental factors for the overall basin as well as the sub-basins.Precipitation was the dominant factor for the overall basin.In the upper basin,elevation was found to be the dominant factor.The dominant factor in the middle basin was precipitation,closely followed by the soil type.In the lower basin,the dominant factor was soil type with a lower q-statistic of 0.13,and the dominant interaction between the elevation and soil type was nonlinearly enhanced(q-statistic = 0.22).     

Revealing ecosystem services relationships and their driving factors for five basins of Beijing

A clear understanding of the relationships among multiple ecosystem services(ESs) is the foundation for sustainable urban ecosystem management. Quantitatively identifying the factors that influence ES trade-offs and synergies can contribute to deepening ES research, from knowledge building to decision making. This study simulated soil conservation, water yield and carbon sequestration in Beijing, China, from 2015–2018. The spatial trade-offs and synergies of these three ESs within the five major river basins in Beijing were explored using geographically weighted regression. Furthermore, geographical detector was applied to quantitatively identify the driving mechanism of the environmental factors for the ES trade-offs and synergies. The results show the following:(1) the spatial relationships between soil conservation and water yield, as well as between water yield and carbon sequestration, were mainly trade-offs. There was a spatial synergy between soil conservation and carbon sequestration.(2) Regarding the spatial trade-off/synergy between soil conservation and water yield in Beijing, the dominant influencing factor was temperature/elevation, and the dominant interactions of the spatial trade-off and synergy between these two ESs in Beijing and the Chaobai River Basin are all manifested in the superposition of precipitation and potential evapotranspiration, temperature, and elevation.(3) Topographic factors were the dominant factors influencing the spatial relationship between soil conservation and carbon sequestration in Beijing and its five major river basins. As a result of the distribution of water systems and hydrological characteristics of the basins, differences were observed in the effects of different combinations of interaction factors on the spatial relationship between these two ESs in different basins.(4) Temperature had the strongest explanatory power in terms of the spatial trade-offs and synergies between water yield and carbon sequestration. The interactions between precipitation and temperature and between precipitation and elevation were the dominant interactions affecting the spatial relationship between water yield and carbon sequestration in Beijing. Overall, the explanatory power of influencing factors on the trade-offs and synergies and the degree of interaction between factors coexist in different basins with consistency and differences. Therefore, understanding the quantitative characteristics of basin-scale spatial trade-offs and synergies between ESs is important for ecosystem management and the promotion of synergy in different basins.     

Assessment and analysis of ecosystem services value along the Yangtze River under the background of the Yangtze River protection strategy

The Yangtze River is the third largest river in the world and the longest and largest river in China.China has adopted a national strategy to protect the Yangtze River.A better understanding of the ecosystem services value along the Yangtze River would provide support for the Yangtze River protection strategy.Using Costanza’s method to estimate the ecosystem services value,the value of 10 ecosystem services was estimated within 1 km and 2 km from the Yangtze River in 2017.These 10 services were derived from the four established groupings of provisioning,regulating,supporting,and cultural services.This study compared and analyzed the changes in the ecosystem services value in the upper,middle,and lower reaches of the river,and in provinces,cities,and villages along the Yangtze River.The total ecosystem services value within 1 km and 2 km from the river was 37.208 and 43.769 billion yuan,respectively.Within 1 km,the ecosystem services value in the middle reaches was 12.93 billion yuan,while the next highest value was in the upper reaches at 12.45 billion yuan,and the downstream area had the smallest value of 11.855 billion yuan.Within 2 km,the value of upstream ecosystem services was the highest at 16.31 billion yuan,while the second highest value was in the middle reaches at 14.376 billion yuan,and the smallest value was in the downstream area at 13.083 billion yuan.In the Yangtze River Basin,regulating services played a leading role,accounting for 81.6%and 78.9%of the ecosystem services value within 1 km and 2 km from the river,respectively.Among the 10 ecosystem services,hydrological regulation was the most important,while the value of raw material production made the smallest contribution.Among the provinces and cities along the Yangtze River,the highest ecosystem services value was in Hubei Province,while the lowest values were in Shanghai and the Qinghai-Tibet Plateau.If villages within 1 km and 2 km from the river were to be relocated,the total regional ecological value would increase by 527 and 975 million yuan,respectively.     

ADULT DRAGONFLY COMMUNITIES IN TROPICAL RIVERS OF THE NORTHERN PENINSULAR MALAYSIA： SPECIES COMPOSITION, BIOTOPE AND HOST PLANT PREFERRENCES

1INTRODUCTION Manyfactorshavebeenlinkedwithobserved patternsofodonatediversity.Eachhabitatisdifferent andpresentsitsownopportunitiesforexploitationby welladaptedspecies(Krebs,1989).Theyaresensi tiveresponderstonewlycreatedphysicalandtogether withphysiogra…     

辽河流域生态需水估算

从辽河流域存在的环境问题出发,在确定主要生态需水类型的基础上,基于水资源分区,分别估算各水资源分区的不同类型的生态需水,包括枯季河道生态需水、汛期输沙需水、入海需水、地下水恢复需补充的水量、河口湿地生态需水等。针对辽河流域季节性河流的特点,提出了枯水季节最小流量法的枯季河道生态需水计算方法。计算结果表明,辽河流域生态需水总量为130.44×10⁸m³,占地表径流的48.3%,其中浑太河、东辽河2个水资源分区的生态需水量占地表径流的比例在60%以上,辽河干流生态需水量占地表径流的53.5%,其余水资源分区生态需水量占地表径流的比例均在50%以下。研究结果为流域水资源配置及水环境保护与恢复提供科学依据。     

黄河中下游水沙变化趋势

本文论述由于黄河上游清水区水资源的优先开发,中上游地区工农业用水的增长,而黄河中游地区的水土保持和支流治理的减沙作用不甚明显,龙羊峡水库投入运用后,汛期进入河口镇的水量大幅度减少,使汛期进入黄河下游的基流减小含沙量增加,高含沙洪水出现的机会增多.面临水少沙多的不利情况,应加强宽浅河道的改造及利用窄深河道输送高含沙水流的研究.     

三峡水库不同类型支流河口泥沙淤积成因及趋势

为揭示三峡水库库区不同类型支流河口泥沙淤积的内在机理和变化趋势,本文充分利用水文、泥沙、固定断面和河道地形等原型观测资料,从支流水沙输移规律和河口局部水沙分布特征出发,研究了不同类型支流河口段泥沙淤积规律及主要影响因素的作用机理,探讨其淤积趋势及形成拦门沙的风险。结果表明:三峡水库蓄水后,库区不同类型支流河口普遍淤积,淤积范围及河道形态的变化各有特点;水库蓄水造成水动力条件减弱是河口泥沙淤积的根本原因,淤积幅度和范围主要取决于干支流来沙量和局部河势。在干支流来沙均明显减少的情况下,三峡水库库区支流河口泥沙淤积速度显著下降,形成拦门沙坎的可能性较小。     

Neotectonic evolution of the northern Laborec drainage basin (northeastern part of Slovakia)

This study investigates the influence of neotectonic activity on river and basin patterns in a mountainous area located in the northeastern part of the Carpathian Belt (the Laborecká vrchovina and Bukovské vrchy Mts. in eastern Slovakia). This area evolved within the accretionary wedge of the Carpathians during the Neogene, and it was alsowas affected by Middle to Late Miocene thrusting of the External Carpathians. Morphometric analysis, longitudinal and transverse river valley profiles, analysis of basin and valley symmetries, and investigation of alluvial terraces were carried out on the northern Laborec River and its tributaries. This was done to detect a possible relationship between their river courses and any ongoing neotectonic activity, which is otherwise difficult to detect by methods of structural geology because of the poorly exposed area.The general topography of the basin is characterized by a stepwise inclination to the SW as a result of differential uplift and subsidence. The reorganization of the river network in the Laborec drainage basin was influenced by tectonic activity along the NE-SW up to N-S fault structures during the neotectonic phase (Pliocene-Quaternary). The movement along these fault structures is predominantly normal to transtensive. The obtained data assumes that the region is under approximately NE-SW oriented S_H compression and NW-SE trending S_h tension. The Laborec drainage basin is characterized by a very high degree of asymmetry that sharply increases from the upper to the lower courses of the river. The right-bank tributaries of the Laborec River are < 12 km in length; however, the left-bank tributaries such as Vydraňka, Ol'šava, Výrava, Udava, and Cirocha Streams are up to 50 km long with a high potential of headward erosion and capturing. The valley asymmetry is also very variable in the upper and lower portions of the basin. Based on these presented results, the ancient river thalweg was located along the axis of the Hostovice-Habura depression, and it was captured by the Ol'šava, Výrava, and Udava Streams. The asymmetric pattern of the drainage basin is the result of active tectonics, the continual subsidence of the Transcarpathian Basin, and by the uplift of the Laborecká vrchovina and Bukovské vrchy Mts. These events caused rejuvenation of the headward erosion of streams in the southern part. Favorable lithology was also essential in the process of river capture.     

无定河流域不同地貌区水沙过程对比

为了查明人为影响程度较低时期无定河流域内不同地貌区的水沙过程及其变化规律,选取1970年以前一段时期该流域内风沙区和黄土丘陵沟壑区河流的有关水文站的水文泥沙实测数据进行对比分析。结果表明,风沙区河流的流量变率较黄土丘陵沟壑区的小;风沙区河流的含沙量远小于黄土丘陵沟壑区河流的含沙量。黄土丘陵沟壑区河流具有极高的输沙率,而风沙区河流的输沙率微不足道。风沙区和黄土丘陵沟壑区河流的产流模数基本相近,但产沙模数非常悬殊,前者的产沙模数很小,为118.58~725.38t /km² · a,而后者的达到1879.36~25112.15t /km² · a。显然,无定河流域黄土丘陵沟壑区的河流是侵蚀产沙的主要来源区,因而是水土保持工作的重点区域。     

伊犁河流域降水和气温的若干特征

本文详细分析了天山山区伊犁河流中低山区降水和气温的变化规律。结果表明，夏季中低山带的降水和气温与其对应高度的关系较好，且梯度值较大；不同年份降水量越大，降水梯度值亦越大，在此基础上结合邻近地区高山区观测资料，获取了伊犁河流域高山区的降水和气温。     

滹沱河上游水系变迁问题的讨论

本文着重讨论了滹沱河上游水系变迁的三个争议较大的问题。研究表明：（１）阳武河袭夺问题是不存在的，其干、支流分别沿ＮＷ和ＮＥ两组性质不同的构造发育而成；（２）奇村宽谷在更新世期间曾长期作为滹沱河汊道与界河铺峡谷并存，后因西部山地河流的超补偿堆积而最终断流。（３）滹沱河是一条先成河，自上新世末形成以来，其总的流路并未改变。石岭关风口早于盆地而形成，可能是一条更古老的河流所造成。     

Response and recovery of the Eel River, California, and its tributaries to floods in 1955, 1964, and 1997

Northwestern California is prone to regional, high magnitude winter rainstorms, which repeatedly produce catastrophic floods in the basins of the northern Coast Ranges. Major floods on the Eel River in 1955 and 1964 resulted in substantial geomorphic changes to the channel, adjacent terraces, and tributaries. This study evaluated the changes and the effects of a moderate flood in 1997 through field observations and examination of aerial photographs that spanned from 1954 to 1996. The purpose was to document the nature and magnitude of geomorphic responses to these three floods and assess the rates and controls on the recovery of the Eel River and its tributaries. Channel widening from extensive bank erosion was the dominant geomorphic change along the lower Eel River during major floods. As a result of the 1964 flood, the largest amount of widening was 195 m and represented an 80% change in channel width. Channel narrowing characterized the periods after the 1955 and 1964 floods. More than 30 years after the 1964 flood, however, the river had not returned to pre-flood width, which suggests that channel recovery required decades to complete. A long recovery time is unusual given that the Eel River is located in an area with a “superhumid” climate and has an exceptionally high sediment yield. This long recovery time may reflect highly seasonal precipitation and runoff, which are concentrated in 3–5 months each winter. In contrast to the main stem of the Eel River, the dominant effects of floods on the tributaries of the Eel River were rapid aggradation of channel bed and valley floor followed by immediate downcutting. Dendrogeomorphic data, aerial photographs, and field observations indicate that thick wedges of gravel, derived largely from hillslope failures in upper reaches of the tributaries, are deposited at and immediately upstream of the mouths of tributaries as the stage of the Eel River exceeded that of the tributaries during major floods. In the waning stages of the flood, the tributaries cut through the gravel at a rate equal to the lowering of the Eel and generated unpaired terraces and nickpoints. The complete process of deposition and incision can occur within a few days of peak discharge. Although reworking of some sediment on the valley floor may continue for years after large floods, channel morphology in the tributaries appears to be a product of infrequent, high magnitude events. The morphology of the tributary channel also appears to be greatly influenced by the frequency and magnitude of mass wasting in headwater areas of small basins.