Major Watersheds Research Articles

Effects of Precipitation and Vegetation Cover on Annual Runoff and Sediment Yield in Northeast China: A Preliminary Analysis

Northeast China is an important food producing area because it contains large areas of organic soil. However, land degradation caused by soil erosion poses a serious threat to the soil conditions in this region. It is therefore crucial to explore the mechanisms behind the soil erosion and transport processes. This study assessed the effects of precipitation and vegetation cover variations on runoff and sediment yield within nine major watersheds in Northeast China, using Pearson correlation and multiple linear regression models. There were significantly positive correlations between annual precipitation, runoff and sediment yield within all watersheds between the 1960s and 2011. In addition, the vegetation index was negatively related to differences within annual water-sediment variables within most of the watersheds from 1982 to the 2010s. Within Songhua River basin, the runoff depth and runoff coefficient had significant positive correlations with NDVI and the proportion of forest. In contrast, the vegetation had negative effects on the runoff within Liao River basin. Spatial analysis of sediment showed that area-specific sediment yield decreased with increasing drainage watershed area, and the correlations between sediment variables and NDVI were stronger within watersheds of the upper reaches and tributaries than large basins in general. The combined effects of precipitation and vegetation influence the erosion and sediment transport processes, and various human activities can influence the routing of sediment to the watershed outlet. If anthropogenic activities such as reservoir and dam construction do not decrease, the protective benefits of vegetation cover may not be realized for a long time, especially along the river mainstream due to the more complex drainage network.

A Genetic Assessment of Missouri's Lake Sturgeon after 30 Years of Restoration Releases

AbstractThe Lake Sturgeon Acipenser fulvescens is native to three major watersheds in the USA: the Great Lakes, Hudson Bay, and Mississippi River drainages. However, they have declined across much of their range due to overfishing, pollution, and major river alterations. After their near extirpation in Missouri, the Missouri Department of Conservation initiated a reintroduction program to restore the Lake Sturgeon in the state's largest waterways. From 1984 to 2015, offspring originating from Lake Winnebago (1984–2001) and from upper Mississippi River tributaries (2004–2015) were reared in captivity and released into portions of the Mississippi and Missouri rivers. After 32 years of restorative releases, we screened Lake Sturgeon samples from the state of Missouri by using 11 microsatellite loci and mitochondrial DNA control region sequences. We examined overall genetic diversity and genetic structure of Lake Sturgeon captured in the Mississippi and Missouri rivers for differences between rivers and among groups within rivers. We found high levels of genetic diversity within both rivers, with very little genetic differentiation between them. Higher‐than‐average relatedness within sample groups and heterozygote excess were consistent with the pattern expected from stocked fish and suggested that closely related fish may have aggregated at stocking sites. We detected two genetic groups in Missouri, reflecting the change in stock source. Haplotypes that may be unique to the Mississippi and Ohio River systems were observed at very low frequencies. Though largely the product of stocking, reproductively mature Lake Sturgeon will likely have sufficient genetic diversity and will have experienced selection pressures in Missouri's large rivers, making them the most appropriate source for further supplementation if it is deemed necessary. We recommend continued research and monitoring of reproductive habits and preservation of multiple spawning sites to continue the long path toward a self‐sustaining Lake Sturgeon population in Missouri's waters.

Possible Increased Frequency of ENSO-Related Dry and Wet Conditions over Some Major Watersheds in a Warming Climate

AbstractPredicting the changes in teleconnection patterns and related hydroclimate extremes can provide vital information necessary to adapt to the effects of the El Niño–Southern Oscillation (ENSO). This study uses the outputs of global climate models to assess the changes in ENSO-related dry/wet patterns and the frequency of severe dry/wet events. The results show anomalous precipitation responding asymmetrically to La Niña and El Niño, indicating the teleconnections may not simply be strengthened. A “dry to drier, wet to wetter” annual anomalous precipitation pattern was projected during La Niña phases in some regions, with drier conditions over southern North America, southern South America, and southern central Asia, and wetter conditions in Southeast Asia and Australia. These results are robust, with agreement from the 26 models and from a subset of 8 models selected for their good performance in capturing observed patterns. However, we did not observe a similar strengthening of anomalous precipitation during future El Niño phases, for which the uncertainties in the projected influences are large. Under the RCP4.5 emissions scenario, 45 river basins under El Niño conditions and 39 river basins under La Niña conditions were predicted to experience an increase in the frequency of severe dry events; similarly, 59 river basins under El Niño conditions and 61 river basins under La Niña conditions were predicted to have an increase in the frequency of severe wet events, suggesting a likely increase in the risk of floods. Our results highlight the implications of changes in ENSO patterns for natural hazards, disaster management, and engineering infrastructure.

Isotopic and element ratios fingerprint salinization impact from beneficial use of oil and gas produced water in the Western U.S.

Salinization of global freshwater resources is a concerning health and economic issue of the 21st century and requires serious management and study to understand how, and by what mechanism, Total Dissolved Solids (TDS) is changing in major watersheds. Oil and gas (O&G) produced water is a complex and saline (10-300g/L TDS) wastewater often disposed to surface waters post-treatment. However, in western U.S. states, beneficial use of minimally treated O&G produced water discharged to ephemeral streams is permitted through the USEPA National Pollutant Discharge Elimination System (NPDES) for agriculture and wildlife propagation. In a remote Wyoming study region, beneficial use of O&G NPDES effluents annually contributes 13billionL of water to surface water resources. The primary O&G TDS constituents are sulfate and sodium followed by chloride and calcium. Significant TDS increases from 2013 to 2016 in a large perennial river (River C) impacted by O&G effluent disposal, slight TDS increases in a perennial river (River B) and chronically elevated TDS (upwards of 2500mg/L) in a smaller tributary (Tributary A) comprised mainly of O&G effluents led to an investigation of O&G impacts to surface waters in the region. Chloride-normalized metal ratios such as Br/Cl and δ2H and δ18O distinguished evaporation as the mechanism for increasing TDS derived from O&G on Tributary A, which is causing O&G effluents that meet NPDES regulations to not only exceed outfall regulations downstream where it is beneficially used for irrigation and drinking water but also exceed aquatic life and livestock recommended limits. 87Sr/86Sr and δ34SSO4 suggested minor impacts from O&G TDS loading on River C but also support an additional salinity source, such as streambed geological controls, the cause of significantly increasing TDS. While lithium isotopes provided insight into the O&G effluent origin (δ7Li ranged 9-10‰) and water-sediment interactions along O&G effluent streams, they did not function as distinct salinity tracers in the larger downstream rivers. This study suggests a multi-isotope (87Sr/86Sr and δ34SSO4) approach is often necessary for fingerprinting salinization sources and determining best management practices because multiple salinity sources and environmental mechanisms may need to be identified to protect water quality.

Bald eagle mercury exposure varies with region and site elevation in New York, USA.

Freshwater fish in several regions of New York State (NYS) are known to contain concentrations of mercury (Hg) associated with negative health effects in wildlife and humans. We collected blood and breast feathers from bald eagle (Haliaeetus leucocephalus) nestlings throughout NYS, with an emphasis on the Catskill region to determine their exposure to Hg. We assessed whether habitat type (lake or river), region (Delaware-Catskill region vs. rest of NY) or sample site elevation influenced Hg concentrations in bald eagle breast feathers using ANCOVA. The model was significant and accounted for 41% of the variability in log10 breast feather Hg concentrations. Mercury concentrations in nestling breast feathers were significantly greater in the Delaware-Catskill Region (geometric mean: 14.5 µg/g dw) than in the rest of NY (7.4 µg/g, dw), and greater at nests located at higher elevations. Habitat type (river vs. lake) did not have a significant influence on breast feather Hg concentrations. Geometric mean blood Hg concentrations were significantly greater in Catskill nestlings (0.78 µg/g ww) than in those from the rest of NY (0.32 µg/g). Mercury concentrations in nestling breast feathers and especially blood samples from the Delaware-Catskill region were generally greater than those reported for most populations sampled elsewhere, including areas associated with significant Hg pollution problems. Bald eagles can serve as valuable Hg bioindicators in aquatic ecosystems of NYS, particularly given their broad statewide distribution and their tendency to nest across all major watersheds and different habitat types.

Total Trihalomethane Levels in Major Watersheds across the United States

Trihalomethanes, such as chloroform, bromoform, dibromo(chloro)methane, and bromo(dichloro)methane, are present in the major watersheds across the United States. These chemicals play an important role in the development of cancer, have adverse reproductive outcomes, and were found to be present above the threshold established by the Environmental Protection Agency. To understand the impact of socioeconomic background on the quality of water and possible disparities, we have analyzed the levels of total trihalomethanes in the metropolitan areas in the major watersheds across the United States, in 2018, as they correlated to average household incomes. Our study found that Arkansas, Nevada, and Rhode Island demonstrated higher than federally mandated levels of total trihalomethanes in their watersheds. The median annual household and per capita incomes of the three states (Arkansas, Nevada, and Rhode Island) were lower than the national average. In addition, Delaware, New Hampshire, and Wisconsin, which had higher median income levels, demonstrated the lowest total trihalomethane levels across the United States.

Land use/land cover change along the Eastern Coast of the UAE and its impact on flooding risk

This study was conducted to investigate the spatiotemporal changes of land use/land cover (LULC) along the eastern coast of the United Arab Emirates (UAE) over a 20-year period using an integration of remote sensing and Geographic Information Systems techniques. The impact of land use change on flooding potential was also investigated through hydrologic model simulations. Landsat images of the years 1996, 2006 and 2016 were processed and analyzed. Change detection was carried out to assess changes in the built-up areas. Furthermore, the impact of urbanization on flooding was assessed using a hydrologic model in two major watersheds of Fujairah Emirate. It was observed that for the period 1996–2006 the vegetation and the built-up areas had increased at a rate of 11.23% and 24.56%, respectively. For the period 2006–2016, this expansion more than doubled in terms of the vegetation class (27.51%) and slightly increased for the built-up class (28.98%). The change detection analysis revealed that urbanization has mostly occurred along the coastal boundary. Hydrologic model simulations quantified the role of urbanization in increasing the flooding potential. The increase depends on watershed characteristics and the rate of change in urbanization and the magnitude of the rainfall event.

Unsteady migration of Taebaek Mountain drainage divide, Cenozoic extensional basin margin, Korean Peninsula

The Taebaek Mountain Range (TBR) initially formed via extension of a back-arc basin in the East Sea during the early-Miocene (ca. ~22 Ma) and exemplifies a typical escarpment on a passive continental margin. The TBR acts as a major watershed and divide across which topography changes from gentle western side slopes to steep eastern slopes. Compared to the geologic history of the flanking extensional basin, which is well known from analysis of its sedimentary fill, the post-extensional geomorphic history of the escarpment and basin margin has been minimally studied because of a lack of terrestrial archives. We determined the rate and cause of divide migration of the TBR using a suite of relatively new geomorphic and geochronologic tools. We used geomorphic analyses of relief, slope, river long profiles, swath profiles, and χ parameters to study this transient topography. Catchment-wide denudation rates (CWDR) using 10Be facilitated comparisons of denudation rates of cross-divide paired basins. Denudation rates east of the divide from drainages with steep slopes average nearly two times counterparts with gentle slopes west of the divide. Gilbert metrics used to assess divide mobility strongly suggest that catchments in the eastern TBR may have captured counterpart catchments in the west. Both CWDR and Gilbert metric results reveal that retreat of the main TBR divide likely accelerated in the late Quaternary following tectonic inversion, surface uplift, and tilting or flexure in the eastern TBR. Geomorphic disequilibrium across the current divide of the TBR continues until the present.

Evaluation of Changes in Agricultural Stream Water Quality of Small Watershed in Gyeonggi Province

This study aimed to identify the changing trends in the agricultural water quality of the major watersheds in Gyeonggi Province over a 10-year period ranging from 2007 to 2016. The results of water quality analysis of the study sites revealed that the mean chemical oxygen demand was 3.8 mg L-1, with the median values being 3.5 mg L-1. The mean chemical oxygen demand in April, July, and October were 4.7, 3.8, and 3.1 mg L-1, respectively, and chemical oxygen demand values trended to decrease from April to October. The mean and the median electrical conductivity were 0.22 dS m-1. The mean electrical conductivity values were slightly higher in April and lower in October, and there was no yearly fluctuation. The mean and median values of the T-N (Total Nitrogen) content were 3.3 mg L-1 and 3.0 mg L-1, respectively. The mean and median values of the T-P (Total Phosphorous) content were 0.10 mg L-1 and 0.06 mg L-1, respectively, and there was no tendency to increase or decrease during the April, July and October. Changes in annual water quality index in April (left), July (center), and October (right).

Desertification vulnerability and risk assessment for Turkey via an analytical hierarchy process model

AbstractProducing a scientific desertification risk map has become one of the national primary tasks in order to effectively combat desertification in Turkey. In this respect, General Directorate of Combating Desertification and Erosion in cooperation with TÜBİTAK BİLGEM, generated the Desertification Model of Turkey (DMT), an original geographical and mathematical country‐specific model under the umbrella project called the “Watershed Monitoring and Evaluation System” (HIDS). The DMT is a tool used for estimating land degradation, assessing desertification vulnerability and risk, preparing watershed scale risk maps, and monitoring desertification hot spots of the country. The DMT has been designed to consist of 48 indicators and 37 subindicators under seven main criteria defined by an expertise group and using the analytical hierarchy process. Percentage distribution of desertification risk among watersheds was calculated in nine classes based on the Desertification Risk Map of Turkey and revised in accordance with field surveys carried out in 2016–2017 within the scope of the DMT Verification and Calibration Project. Results for major watersheds of Turkey revealed that at least 15% of lands of all river basins are under moderate–high desertification risk, with the exception of Aras, Western Black Sea, Konya Closed, Marmara, and Meriç–Ergene watersheds. In addition, it was identified that the DMT and the Desertification Risk Map of Turkey present results at an accuracy rate of 84% and with 90% level of confidence at microwatershed scale.

Residential Land Use Change in the Wissahickon Creek Watershed: Profitability and Sustainability?

The Wissahickon Creek Watershed is one of five major watersheds in the Philadelphia metro region. The main objective of the work in this paper was to determine and compare the energy and environmental impacts of placing housing in the Watershed according to profitability and environmental sustainability criteria, respectively, in the context of increasing urbanization. Future population and employment for the Watershed have been projected by the Delaware Valley Regional Planning Commission. Housing requirements for the projected populations in each municipality were computed, and their location was influenced by the local zoning ordinances. Suitability analysis using ArcGIS 10.6 generated areas for development based alternatively on profitability and local sustainability. CommunityViz 5.2 Scenario 360 software was used to place buildings within the appropriately-zoned areas. Using Argonne National Laboratory’s Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET1 2018) software and water quality monitoring information from the Philadelphia Water Department, impacts were directly estimated. The impacts were related to effects on ecosystem functioning, ecosystem goods and services, and broad value estimated for the latter. The effects were used to indicate what might be appropriate policies to reduce the negative environmental consequences of residential development in the watershed. Unexpectedly, the environmental impacts of the profitable and sustainable scenarios were not very different. This suggests that profitability and sustainability need not be mutually exclusive.

Koi herpesvirus and carp oedema virus: Infections and coinfections during mortality events of wild common carp in the United States.

Koi herpesvirus (KHV; cyprinid herpesvirus-3) and carp oedema virus (CEV) are important viruses of common and koi carp (Cyprinus carpio); however, the distribution of these viruses in wild common carp in North America is largely unknown. During the summers of 2017 and 2018, 27 mass mortalities of common carp were reported from four states in the USA (Minnesota, Iowa, Pennsylvania and Wisconsin), the majority of which were distributed across eight major watersheds in southern Minnesota. Samples from 22 of these mortality events and from five clinically healthy nearby carp populations were screened for KHV, CEV and SVCV using real-time polymerase chain reaction (qPCR). KHV was confirmed in 13 mortality events, CEV in two mortality events and coinfections of KHV/CEV in four mortality events. Nucleotide sequence analysis revealed that the KHV and CEV detected here are closely related to European lineages of these viruses. While molecular detection alone cannot conclusively link either virus with disease, the cases described here expand the known range of two important viruses. This is also the first reported detection of KHV and CEV coinfections in wild carp populations.

The Latitudes, Attitudes, and Platitudes of Watershed Phosphorus Management in North America.

Phosphorus (P) plays a crucial role in agriculture as a primary fertilizer nutrient-and as a cause of the eutrophication of surface waters. Despite decades of efforts to keep P on agricultural fields and reduce losses to waterways, frequent algal blooms persist, triggering not only ecological disruption but also economic, social, and political consequences. We investigate historical and persistent factors affecting agricultural P mitigation in a transect of major watersheds across North America: Lake Winnipeg, Lake Erie, the Chesapeake Bay, and Lake Okeechobee/Everglades. These water bodies span 26 degrees of latitude, from the cold climate of central Canada to the subtropics of the southeastern United States. These water bodies and their associated watersheds have tracked trajectories of P mitigation that manifest remarkable similarities, and all have faced challenges in the application of science to agricultural management that continue to this day. An evolution of knowledge and experience in watershed P mitigation calls into question uniform solutions as well as efforts to transfer strategies from other arenas. As a result, there is a need to admit to shortcomings of past approaches, plotting a future for watershed P mitigation that accepts the sometimes two-sided nature of Hennig Brandt's "Devil's Element."

Diversity and conservation status of lichens and allied fungi in the Greater Toronto Area: results from four years of the Ontario BioBlitz

Bioblitzes are typically 24-hour biological surveys of a defined region carried out by taxonomic specialists, citizen scientists, and the general public. The largest in Canada is the Ontario BioBlitz, an annual event held in the Greater Toronto Area (GTA). Between 2013 and 2016, we examined the feasibility of including lichens and allied fungi in the Ontario BioBlitz. These taxa are often overlooked, understudied, and taxonomically difficult. We completed a bioblitz in each of the four major watersheds in the GTA and recorded 138 species in 72 genera which, combined with all previous collections, totals 180 species in 88 genera in the area. Thirteen of the species we collected are provincially ranked as S1 (critically imperilled), S2 (imperilled), or S3 (vulnerable). We collected Lecanora carpinea for the first time in Ontario. Our results provide a baseline list of GTA lichens that can be used for monitoring. This is one of the first detailed lichen surveys of a major North American urban area and it demonstrates that rapid bioblitz surveys are proficient in capturing lichen diversity despite their inconspicuous nature and the advanced microscopy and chemical analyses required for their identification.

Flow dynamics at channel confluences: few observations from a sub-tropical plateau fringe river of Eastern India

River confluences are that critical interfaces where significant changes in channel hydrological processes occurs. How and why these changes occur are the elementary questions for scaling-up our understanding of the dynamic hydrological processes occurring at the catchment scale. Confluences of major watersheds of the Chotonagpur plateau fringe fans (eastern counterpart) unlike other of the Gangetic flood plain are attributed by immensely fluctuating gauge level under the circumstances of high-intensity seasonally skewed rainfall. To understand this regional character and in view of the importance of channel confluences, the manuscript is hereby inclined to document the hydrological dynamism at 11 tributary junction sites along 86.4-km stretched river Bakreshwar of Eastern India. From the field survey of the said 11 confluence junctions constituting 7 channel reaches and 33 cross sections in total, it has been affirmed that the tributary junctions represent locations of sudden change in the longitudinal flow rhythm of the main river. The abrupt changes in channel flow due to tributary influxes of water at the confluences have a fair relation with size and length of the tributary rivers. However, tributary basin runoff volume relative to the main river basin is found to be the most influential factor to regulate post-confluence increase in velocity and discharge. The study reported here is a fundamental work and hopefully stimulate ideas for fruitful and coherent scientific inquiry on river confluences and its management particularly in Indian circumstances.

Release of hatchery-reared brown trout (Salmo trutta) as a threat to wild populations? A case study from Austria

In spite of growing evidence pointing to ecological and genetic risks to wild fish populations, artificial propagation and stocking remain common practices for recreational fishery management. Moreover, even a cursory level of monitoring and evaluation of these risks is neglected, especially where fisheries are managed by private entities. Against this backdrop and with the goal of establishing a more integrated system of ecosystem-based management, this study aims to identify potential threats from the current practices and patterns of brown trout management in Austria. We surveyed 26 private brown trout hatchery operations in three Austrian provinces to examine and categorize the practices in the production of brown trout for stocking. Specifically, we examined the rearing practices and the “trading networks” among trout farmers for characteristics such as rearing history, operating principles, broodstock origins and maintenance, and output figures. Several risk-associated practices emerged, including introduction of brood from divergent lineages outside of Austrian watersheds, translocation and mixing of fish across major watersheds within Austria, and reinforced domestication across multiple generations of captivity. These practices jeopardize native populations by disrupting local adaptations resulting from mixing of native and non-native lineages, reducing genetic diversity within lineages from population bottlenecks, and lowering success of wild populations from domestication selection within the hatchery environment. The findings, which identify threats rather than directly measure impacts, are discussed within the context of concerns on the role of conserving intraspecific diversity for native brown trout fisheries. We conclude by suggesting the integration of ecological and genetic principles into propagation and stocking practices to achieve fishery management strategies more compatible with maintaining natural diversity and adaptive potential of brown trout in Austria.

Effect of riparian vegetation clear-cutting on avian community in the Northern Negev

In arid zones, riparian corridors serve as important habitats, offering water, nutrients, shelter and optimal microclimate conditions to many organisms. In the northern Negev desert of Israel, several large rivers cross through the arid landscape, with Saltcedar (Tamarix spp.) being the climax vegetation. Although these rivers have been continuously subjected to management, human control became much more frequent and thorough since the early 2000s. Current management involves vegetation clear-cutting of long riverbed sections. In arid zones such as the Negev, where trees are scarce and restricted to streams, such activity may affect wildlife at all hierarchical levels. Being one of the most successful invasive trees in North America, many aspects of Saltcedar management along rivers have been explored around the USA. Notably, how riparian Saltcedar forests in the old world, where it is native, influence wildlife, has not been studied. We explored the effects of vegetation clear-cutting on bird communities at three sites in the Northern Negev of Israel, comparing bird abundance, richness and diversity between natural and managed riparian transects. All three variables were significantly lower in managed sites. Species composition shifted from tree-dwelling species in natural transects to ground-dwelling species in clear-cut sections. Natural sections were characterized by lower ambient temperature, lower radiation, and higher relative humidity. Our findings may explain the long-term reduction observed in local bird populations in the northern Negev. They also indicate the importance of the Saltcedar forests along major watersheds in the Northern Negev for bird populations.

Drift happens: Molecular genetic diversity and differentiation among populations of jewelweed (Impatiens capensis Meerb.) reflect fragmentation of floodplain forests.

Landscape features often shape patterns of gene flow and genetic differentiation in plant species. Populations that are small and isolated enough also become subject to genetic drift. We examined patterns of gene flow and differentiation among 12 floodplain populations of the selfing annual jewelweed (Impatiens capensis Meerb.) nested within four river systems and two major watersheds in Wisconsin, USA. Floodplain forests and marshes provide a model system for assessing the effects of habitat fragmentation within agricultural/urban landscapes and for testing whether rivers act to genetically connect dispersed populations. We generated a panel of 12,856 single nucleotide polymorphisms and assessed genetic diversity, differentiation, gene flow, and drift. Clustering methods revealed strong population genetic structure with limited admixture and highly differentiated populations (mean multilocus FST =0.32, FST '=0.33). No signals of isolation by geographic distance or environment emerged, but alleles may flow along rivers given that genetic differentiation increased with river distance. Differentiation also increased in populations with fewer private alleles (R2 =0.51) and higher local inbreeding (R2 =0.22). Populations varied greatly in levels of local inbreeding (FIS =0.2-0.9) and FIS increased in more isolated populations. These results suggest that genetic drift dominates other forces in structuring these Impatiens populations. In rapidly changing environments, species must migrate or genetically adapt. Habitat fragmentation limits both processes, potentially compromising the ability of species to persist in fragmented landscapes.

HUBUNGAN SEBARAN MAMALIA KECIL DENGAN KONDISI LINGKUNGAN DI HULU DAS CITANDUY, JAWA BARAT

Citanduy watershed is one of major watersheds in Java that located through north to south covering four regencies, these are: Ciamis, Tasikmalaya, Garut and Cilacap. As a consequences of environmental changes, this watershed that covering an are about 473.967 ha has faced in deterioration on its roles. This research was aimed to study on the distribution of small mammals at the upper of Citanduy watershed according to their habitat and altitudinal changes. Results indicated that 20 species of small mammals clustered in three groups of habitat. Group 1 consisted of small mammals that occupied the habitat of mixed pines-calliandra. Group 2 comprised of small mammals lived at secondary forest, bambu plantation, and mixed secondary forest-bamboo; and group 3 were mainly occupied shrub. In addtion, an altitude was also affected the distribution of small mammals in the area surveyed. The results of this study are to be used as a basic information that describe the quality of upper Citanduy watershed.

Rapid assessment of the riparian zone habitat of river.

Some riparian areas of the country are in danger of deterioration due to uncontrolled exploitation coupled with loose implementation of environmental protection policies and regulations. Muleta River, a major watershed in Bukidnon, Philippines, was assessed to determine the present condition of its riparian habitat. Abiotic and biotic conditions of the river were assessed. Other factors including land cover, population density, and river geomorphologic characteristics contributing to the river condition were also evaluated. Results revealed that Muleta Watershed is in sub-optimal condition signifying favorable condition for floral and faunal habitat. However, considerable degradation in some isolated cases was likewise spotted. Biotic condition has shown greater degradation approaching marginal condition compared to the abiotic condition which is yet in the upper sub-optimal condition. It was found out that the midstream portion of the watershed is the most disturbed, followed by the downstream area and lastly by the upstream portion. The extent of agricultural cultivation is found as one of the significant factors affecting the health of the riparian habitat areas. It is recommended that riparian protection policies must be formulated and implemented to abate, if not prevent, the impact of anthropogenic interventions resulting to overexploitation in the riparian areas especially in midstream portion of the river.