River Nutrient Loads and Catchment Size

We have used a total of 496 sample sites to calibrate a simple regression model for calculating dissolved inorganic nutrient fluxes via runoff to the ocean. The regression uses the logarithms of runoff and human population as the independent variables and estimates the logarithms of dissolved inorganic nitrogen and phosphorus loading with R² values near 0.8. This predictive capability is about the same as has been derived for total nutrient loading with process-based models requiring more detailed information on independent variables. We conclude that population and runoff are robust proxies for the more detailed application, landscape modification, and in-stream processing estimated by more process-based models. The regression model has then been applied to a demonstration data set of 1353 river catchments draining to the sea from the North American continent south of the Canadian border. The geographic extents of these basins were extracted from a 1-km digital elevation model for North America, and both runoff and population were estimated for each basin. Most of the basins (72% of the total) are smaller than 10³ km², and both runoff and population density are higher and more variable among small basins than among larger ones.While total load to the ocean can probably be adequately estimated from large systems only, analysis of the geographic distribution of nutrient loading requires consideration of the small basins, which can exhibit significant hydrologic and demographic heterogeneity between systems over their range even within the same geographic region. High-resolution regional and local analysis is necessary for environmental assessment and management.     

Effects of Catchment and Riparian Landscape Setting on Water Chemistry and Seasonal Evolution of Water Quality in the Upper Han River Basin,China

Six-year (2005–2010) evolution of water chemistry (Cl⁻, NO₃ ⁻, SO₄ ²⁻, HCO₃ ⁻, Na⁺, K⁺, Ca²⁺ and Mg²⁺) and their interactions with morphological properties (i.e., slope and area), land cover, and hydrological seasonality were examined to identify controlling factors and processes governing patterns of stream water quality in the upper Han River, China. Correlation analysis and stepwise multiple regression models revealed significant correlations between ions (i.e., Cl⁻, SO₄ ²⁻, Na⁺ and K⁺) and land cover (i.e., vegetation and bare land) over the entire catchment in both high- and low-flow periods, and in the buffer zone the correlation was much more stronger in the low-flow period. Catchment with steeper slope (>15°) was negatively correlated with major ions, largely due to multicollinearity of basin characteristics. Land cover within the buffer zone explained slightly less of major elements than at catchment scale in the rainy season, whereas in the dry season, land cover along the river networks in particular this within 100 m riparian zone much better explained major elements rather than this over the entire catchment. Anthropogenic land uses (i.e., urban and agriculture) however could not explain water chemical variables, albeit EC, TDS, anthropogenic markers (Cl⁻, NO₃ ⁻, SO₄ ²), Na⁺, K⁺ and Ca²⁺ significantly increased during 2005–2010, which was corroborated by principal component analyses (PCA) that indicated anthropogenic inputs. Observations demonstrated much higher solute concentrations in the industrial-polluted river. Our results suggested that seasonal evolution of water quality in combined with spatial analysis at multiple scales should be a vital part of identifying the controls on spatio-temporal patterns of water quality.     

Restoration of Catchment Water Balance: Responses of Clonal River Red Gum (Eucalyptus camaldulensis) to Waterlogging

Effects of waterlogging were studied in the field and under glasshouse conditions on two clonal lines of Eucalyptus camaldulensis Dehnh (river red gum), which are used in the rehabilitation of damaged agricultural catchments in Western Australia. The plantation of 9-year-old trees was in a position that covered a range of waterlogging and salinity conditions. Up-slope the water table was deeper (0.65–1.5 m), whereas the water table was closer to the ground surface down-slope (0.45 m in winter; 1.25 m in summer). Salinity was greater downslope and increased at the end of the dry summer, remaining high until diluted by the winter rains. Trees of both clonal lines were smaller downslope and used less water over the year. Clone M80 used more water in winter; clone M66 more in summer. In the field, the roots of clone M80 were evenly distributed through the soil profile, while roots of clone M66 decreased with increasing depth. Production of new root terminals varied with season. Greatest production was in spring and early summer, with much lower production over late autumn and winter. Only clone M66 produced new root terminals at depth (60–75 cm) during the drier months of late summer and early autumn. At this time, saline ground-water was the main source for water uptake. To explore clonal differences more closely, the effects of prolonged waterlogging were studied under glasshouse conditions. Clone M80 grew similarly under freely drained and continuously waterlogged conditions for the experimental period (21 weeks). The response under continuously waterlogged conditions was achieved through adventitious root production. By contrast, growth of clone M66 was suppressed under continuous waterlogging, a response associated with the lack of adventitious root production. The results from field and glasshouse studies suggest that clone M80 is more adapted to waterlogging by relatively fresh water than clone M66, but that clone M66 may use water of higher salinity than clone M80. Clone M80 would be better suited to higher positions in partially cleared catchments, where rainfall provides relatively fresh soil water. Clone M66 is better suited to lower catchment positions due to its ability to utilize more saline groundwater. Restoration of the water balance of damaged agricultural catchments can be best managed by matching specialized genotypes with particular catchment positions.     

Personal Meaning, Self-Representation, and Agency in Some Recent Works

Inuit Morality Play: The Emotional Education of. Three-Year-Old. Jean L. Briggs. New Haven, CT: Yale University Press, 1998. 275 pp.
The Power of Feelings: Personal Meaning in Psychoanalysis, Gender, and Culture. Nancy J. Chodorow. New Haven, CT: Yale University Press, 1999. 320 pp.
Identity and Agency in Cultural Worlds. Dorothy Holland. William Lachicotte Jr. Debra Skinner. and Carol Cain. Cambridge, MA: Harvard University Press, 1998. 349 pp.     

长江下游发现香鱼的稚鱼

长江靖江江段位于长江最下游,接近河口段。在对这一江段沿岸的鱼类进行调查的过程中,发现在2004年5月11日的渔获物中,有1尾体长70.8mm、体重3．34g的香鱼（Plecoglossus altivelis）稚鱼。这是香鱼在长江流域的首次分布报道。     

Resilient Cosmologies: Water Deities and Divine Agency in Post-Mao China

ABSTRACT

This article explores ritual practices among the Premi people in Southwest China at the beginning of the new millennium. Living in the periphery of Tibetan, Han Chinese and other Tibeto-Burman ethnic groups, Premi villagers have continued to keep an understanding of how the world works that is markedly different from their neighbours. The all-encompassing economic development of China is posing new challenges to the intangible entities in Premi cosmology. In its management of forests, waterways or birth control, the Chinese state is increasingly interfering with Premi ways of dealing with their surroundings. The chapter proposes to focus on the way one category of intangible entities of Premi cosmology, the lwéjabu or water deities, are seen as acting towards these challenges, rather than on the underlying ontological changes. An event where a member of a neighbouring ethnic group becomes an unwitting participant in a Premi medium séance makes the case for approaching extra-human forms of agency by beginning with the ‘work’ or ‘effect’ of the divine entities.     

窟野河流域河川基流量变化趋势及其驱动因素

河川基流量的变化是区域气候变化与人类活动的综合反映,其对维持生态系统健康具有重要的意义.以黄土高原水蚀风蚀交错区典型流域窟野河流域为研究对象,利用1959-2005年实测水文、气象资料,基于Chapman-Maxwell数字滤波法的基流量计算,分析窟野河流域河川基流量的变化趋势与演变特征,从气候变化和人类活动两方面探讨了河川基流量变化的驱动因素.结果表明:(1)近50年来,流域内7个时段(全年;春季、夏季、秋季、冬季;汛期、非汛期)的基流量均表现为极显著减少趋势,全年基流量的减少量为0.628 mm/a,并在1980和1996年发生两次明显的突变;(2)与基准期(1959-1979年)相比,水土保持效应期(1980-1995年)的全年日基流量在5％,50％和95％的频率上相对减少率分别为30％,38％和54％,煤炭开发期(1996-2005年)的全年日基流量在5％,50％和95％的频率上相对减少率分别为57％,68％和100％;(3)流域河川基流量减少是气候变化和人类活动共同作用的结果,降水量的变化一定程度影响基流量,但主要驱动因素是流域内大面积连片开采煤炭资源和过量开发利用地下水.     

Heavy Metal Contamination in Sediments and Floodplain Topsoils of the Lean River Catchment,China

Heavy metals (Cd, Ni, Cu, Pb, and Zn) and total sulfur (TS) in both surficial sediments and adjacent floodplain topsoils of the Lean River catchment are investigated to comprehend the effects of flooding on heavy metals in soils, the evolution of the quality of sediments, and transfer of sediment metals. The results show that concentrations of metals except for Ni in soils are significantly correlated with those in sediments. At most upstream or downstream locations, sediment metal concentrations are found comparable to those in soils (sed/soil≈1). For Cu at locations close to the Dexing Copper Mine (DCM), flooding brought Cu-poor clays into the floodplain soil system and this leads to sed/soil<1, while at locations adjacent to the Yinshan Lead-zinc Mine (YLM), suspended solids containing high concentrations of iron and magnesium oxide absorb large quantities of dissolved Cd, Pb, and Zn and deposit on the floodplain during flooding (sed/soil>1). In spite of an elevated Cu production of the DCM, a significant decrease in sediment Cu concentrations is found as compared to those 10 years ago. The decrease may be due to the elevated Cu ore utilizing efficiency and the use of a new modern tailing pool. At the location closest to the Yinshan Lead-zinc Mine (YLM), Pb and Zn concentrations increased in recent sediments. In the Lean River, metal contamination in sediments cannot reach the location 60 km downstream of their sources in 2005.     

Anthropogenic Transformation Disconnects a Lowland River From Contemporary Carbon Stores in Its Catchment

Ecosystems - Rivers transport carbon from continents to oceans. Surprisingly, this carbon has often been found to be centuries old, not originating from contemporary plant biomass. This can be...     

Landscape Agency and Evenki-Iakut Reindeer Husbandry Along the Zhuia River,Eastern Siberia

This interdisciplinary study applies a series of environmental tests developed in Fennoscandia to elaborate the patterns created by contemporary and past reindeer husbandry along the Zhuia River, Bodaibo district, Irkutsk oblast’, Russian Federation. We successfully used pollen and fungal spore analysis to document the long-term use of one site by ungulates–although it remains unclear if these animals were ‘domestic’ reindeer or not. The date of occupation could go as far back as the fourteenth century. The on-site phosphate analysis, attempted for the first time in Eastern Siberia, proved a useful tool for locating the sites of animal action although failed to specify the boundaries of that action. It did emphasise the importance of accounting for the agency of wind in ordering reindeer behaviour. Finally, the combined phosphate, botanical, and pollen work documented a history of succession of types of land-use from the hunting of Rangifer, to holding Rangifer, to the maintenance of meadows for horses or cattle, to the formation of cereal crops and vegetable patches. The combined use of these methods and a discussion of the ambiguities they produced suggests that they are best employed to find distinctive sites in the landscape which attract both people and animals and are less effective in documenting a Euro-American vision of trust or domination in human-animal relations.     

香溪河流域一条一级支流河岸林凋落物季节动态

对神农架南坡的一条一级支流河岸林的凋落物进行了一年的连续收集研究。结果表明：凋落物干重年输入量为438．72g／m^2,其中树叶凋落物是凋落物的主要成分,占整个凋落物年产量的84％。凋落物的输入明显存在季节性的时间格局。凋落物在秋季的产量占全年产量的75％,春季占6．2％,夏季占13．6％,冬季为5．5％。凋落物组成中,树叶和花果的产量显示出季节变化的趋势;枝条的产量并未显示出明显的季节趋势。在秋季,树叶的产量占全年树叶总量的83％;枝条最高值出现于秋季,产量占全年总员的29％;花果在整个凋落物中所占比重分小,最高值出现在夏季,占年产量的63％。着生藻类的密度月际间的变化较大,存在着显著的差异。最大值与最小值的出现月份与凋落物最大、最低值的出现月份相同。通过统计分析表明,着生藻类的密度变化与凋落物和树叶凋落物的动态具有明显的相关性。     

Enterocytozoon bieneusi Genotypes in Cattle on Farms Located within a Water Catchment Area

Enterocytozoon bieneusi is a microsporidian found in humans and other animals around the world. Investigations in some countries, such as the U.S., have indicated the importance of E. bieneusi as a zoonotic water‐ and food‐borne pathogen. However, there is scant epidemiological information on E. bieneusi in animals in many countries including Australia. Here, we conducted the first molecular epidemiological study of E. bieneusi in farmed cattle in Victoria, Australia, to assess whether these bovids are carriers of “zoonotic” genotypes of E. bieneusi. A total of 471 individual faecal samples were collected from calves of < 3 mo and of 3–9 mo of age. Genomic DNAs were extracted from individual faecal samples and then subjected to nested PCR‐based sequencing of the internal transcribed spacer (ITS) of nuclear ribosomal DNA to identify E. bieneusi and define genotypes. Enterocytozoon bieneusi was detected in 49 of the 471 samples (10.4%). An analysis of ITS sequence data revealed three known genotypes (BEB4, I, and J) and three novel genotypes (designated TAR_fc1 to TAR_fc3). Phylogenetic analysis showed that genotypes BEB4, I, J, TAR_fc1, and TAR_fc2 clustered with genotypes identified previously in humans, indicating that cattle are carriers of E. bieneusi with zoonotic potential.     

Water and community development in the Little Colorado River Basin

Water has historically been a critical limiting factor affecting community development throughout the American West. Within the Little Colorado River Basin of northeastern Arizona, abundant groundwater resources enabled local agricultural communities to overcome the limitations of unstable surfacewater sources. However, industrialization has led to sharp increases in groundwater consumption in the basin and to a decline in groundwater levels and/or quality at several locations. This paper examines the broader historical and regional implications of recent groundwater changes in the basin. Emphasis is placed upon the relationship between local developments and the rapid expansion of metropolitan centers in southern Arizona.     

Contribution by farmers' survival strategies to soil erosion in the Linthipe River Catchment: implications for biodiversity conservation in Lake Malawi/Nyasa

Sediment discharge into Lake Malawi is threatening its ecologicalimportance, thereby inflicting serious socio-economic consequences upon peopledependent on this ecosystem. The discharge is attributed to high rates oferosion in the Lake's catchment, principally occurring on agriculturalland. This study examines how survival strategies, such as expansion ofcultivated farmland and use of low fertilizer application rates, enhance thelikelihood of erosion in the Linthipe River Catchment – one of theLake's important river catchments. As such, it shows that the magnitude oferosion is significantly correlated to the amount of farmland cultivated byestate farmers and smallholders (r = 0.18,P = 0.03, and r = 0.19,P = 0.003 respectively). The low correlation coefficientsuphold the long-established fact that physical variables such as soilerodibility (vulnerability of soil to erosion), rainfall erosivity (thepotential of rainfall to cause erosion), and topography, also play major rolesin erosion processes. Nonetheless they do show that area of cultivated landcontributes to erosion. Additionally, the study shows that yields of importantcrops such as maize and tobacco are low because of insufficient use offertilizers. To compensate for the low yields, farmers rely on extending sizesof land that they cultivate thereby exposing more land to erosive forces ofrainfall. The study, therefore, concludes that Lake Malawi's biodiversityis under threat. In order to sustain the biodiversity, it is necessary toeliminate the need to increase farmland by means of agricultural intensificationthat incorporates appropriate soil-conservation measures.