Evaluation of the host-specificity and prevalence of enterococci surface protein (esp) marker in sewage and its application for sourcing human fecal pollution

The suitability of the enterococci surface protein (esp) marker to detect human fecal pollution was evaluated by testing 197 fecal samples from 13 host groups in Southeast Queensland, Australia. Overall, this marker was detected in 90.5% of sewage and septic system samples and could not be detected in any fecal samples from 12 animal host groups. The sensitivity of the esp primer to detect the human-specific esp marker in sewage and septic samples was 100 and 67%, respectively. The overall specificity of this marker to distinguish between human and animal fecal pollution was 100%. Its prevalence in sewage was also determined by testing samples from the raw sewage, secondary effluent, and treated effluent of a sewage treatment plant (STP) over five consecutive days. Of the 15 samples tested, 12 (80%) were found to be positive for this marker. In contrast, it was not found in three samples from the treated effluent and these samples did not contain any culturable enterococci. The PCR limit of detection of this marker in freshwater samples was up to dilution 1 x 10(-4) and the number of culturable enterococci at this dilution was 4.8 x 10(1) +/- 7.0 x 10 degrees colony forming unit (CFU). The utility of this marker was evaluated by testing water samples from three non-sewered catchments in Pine Rivers in Southeast Queensland. Of the 13 samples tested, eight were positive for this marker with the number of enterococci ranging between 1.8 x 10(3) to 8.5 x 10(3) CFU per 100 mL of water. Based on the results, it can be concluded that the esp marker appears to be sewage specific and could be used as a reliable marker to detect human fecal pollution in surface waters in Southeast Queensland, Australia.     

Habitat and Biodiversity of On-Farm Water Storages: A Case Study in Southeast Queensland, Australia

On-farm water storages (locally known as farm dams or farm ponds) are an important part of many agricultural landscapes, as they provide a reliable source of water for irrigation and stock. Although these waterbodies are artificially constructed and morphologically simple, there is increasing interest in their potential role as habitat for native flora and fauna. In this article, we present results from a case study which examined the habitat characteristics (such as water physical and chemical parameters, benthic metabolism, and macrophyte cover) and the macrophyte and macroinvertebrate biodiversity of eight farm ponds on four properties in the Stanley Catchment, Southeast Queensland, Australia. Each landowner was interviewed to allow a comparison of the management of the ponds with measured habitat and biodiversity characteristics, and to understand landowners’ motivations in making farm pond management decisions. The physical and chemical water characteristics of the study ponds were comparable to the limited number of Australian farm ponds described in published literature. Littoral zones supported forty-five macroinvertebrate families, with most belonging to the orders Hemiptera, Coleoptera, Odonata, and Diptera. Invertebrate community composition was strongly influenced by littoral zone macrophyte structure, with significant differences between ponds with high macrophyte cover compared to those with bare littoral zones. The importance of littoral zone macrophytes was also suggested by a significant positive relationship between invertebrate taxonomic richness and macrophyte cover. The landowners in this study demonstrated sound ecological knowledge of their farm ponds, but many had not previously acknowledged them as having high habitat value for native flora and fauna. If managed for aquatic organisms as well as reliable water sources, these artificial habitats may help to maintain regional biodiversity, particularly given the large number of farm ponds across the landscape.     

Linking river, floodplain, and vadose zone hydrology to improve restoration of a coastal river affected by saltwater intrusion

Floodplain forests provide unique ecological structure and function, which are often degraded or lost when watershed hydrology is modified. Restoration of damaged ecosystems requires an understanding of surface water, groundwater, and vadose (unsaturated) zone hydrology in the floodplain. Soil moisture and porewater salinity are of particular importance for seed germination and seedling survival in systems affected by saltwater intrusion but are difficult to monitor and often overlooked. This study contributes to the understanding of floodplain hydrology in one of the last bald cypress [Taxodium distichum (L.) Rich.] floodplain swamps in southeast Florida. We investigated soil moisture and porewater salinity dynamics in the floodplain of the Loxahatchee River, where reduced freshwater flow has led to saltwater intrusion and a transition to salt-tolerant, mangrove-dominated communities. Twenty-four dielectric probes measuring soil moisture and porewater salinity every 30 min were installed along two transects-one in an upstream, freshwater location and one in a downstream tidal area. Complemented by surface water, groundwater, and meteorological data, these unique 4-yr datasets quantified the spatial variability and temporal dynamics of vadose zone hydrology. Results showed that soil moisture can be closely predicted based on river stage and topographic elevation (overall Nash-Sutcliffe coefficient of efficiency = 0.83). Porewater salinity rarely exceeded tolerance thresholds (0.3125 S m(-1)) for bald cypress upstream but did so in some downstream areas. This provided an explanation for observed vegetation changes that both surface water and groundwater salinity failed to explain. The results offer a methodological and analytical framework for floodplain monitoring in locations where restoration success depends on vadose zone hydrology and provide relationships for evaluating proposed restoration and management scenarios for the Loxahatchee River.     

A land management history for central Queensland,Australia as determined from land-holder questionnaire and aerial photography

Features of the land management history over a 125,755 km(2) area of central Queensland, Australia were determined from a variety of sources. A random sample of 205 site locations provided the basis for determining trends in land use. Trends in vegetation clearing were determined using sequential aerial photography for the sample sites, revealing a steady rate averaging nearly 1% of the region per annum over 41 years. This measure of sustained clearing over a large region is higher than recently published clearing rates from South America. Land types have been selectively cleared with over 90% of the Acacia on clay land type having been cleared. A land-holder questionnaire pertaining to the random sites yielded a response rate of 71% and provided information on vegetation clearing, ploughing, tree killing (ring-barking or tree poisoning), and fire frequency, season and intensity. The land-holder responses were compared with independent data sources where possible and revealed no mis-information. However, land-holders may have been marginally less likely to respond if the sample area had been cleared, although this effect was not statistically significant. Ploughing and tree killing are variable depending on land type, but the former has affected about 40% of the Acacia on clay land type, effectively eliminating options for natural regrowth. The proportion of decade-site combinations that were reported as having no fires increased from 22% in the 1950s to an average of 42% for subsequent decades, although the reporting of more than one fire per decade has been relatively constant through the study period. The reporting of at least one fire per decade varies from 46% for the Acacia on sand land type to 77% for the Eucalypt on sand land type for decade-site combinations. Fires are more intense when associated with clearing than in uncleared vegetation, but the proportion of cool and hot fires is relatively constant between land types in uncleared vegetation. Nearly all fires reported were either in spring or summer and this seasonally restricted regime is probably at variance with Aboriginal fire regimes. This study describes the rapid transformation of central Queensland. This has yielded substantially increased agricultural production but may also result in a range of negative impacts and these are discussed.     

Evaluating slurry broadcasting and injection to ley for phosphorus losses and fecal microorganisms in surface runoff

The recent growth in the size of dairy cattle farms and the concentration of farms into smaller areas in Finland may increase local water pollution due to increased manure production and slurry application to grass. Therefore, a field study was conducted to monitor losses of total phosphorus (TP), dissolved reactive phosphorus (DRP), and fecal microorganisms in surface runoff from a perennial ley. Cattle slurry was added once a year in June 1996-1997 (Study I) and biannually in June and October 1998-2000 (Study II). The slurry was surface broadcast or injected into the clay soil. The field had a slope of 0.9 to 1.7%. Mineral fertilizer was applied on control plots. Biannual slurry broadcasting increased DRP (p < 0.001) and TP losses (p < 0.001) and numbers of fecal microorganisms in surface runoff waters. The highest losses of TP (2.7 kg ha(-1) yr(-1)) and DRP (2.2 kg ha(-1) yr(-1)) and the highest numbers of fecal coliforms (880 colony-forming units [CFU] per 100 mL) and somatic coliphages (2700 plaque-forming units [PFU] per 100 mL) were measured after broadcasting slurry to wet soil followed by rainfall in fall 1998. Injection reduced the TP and DRP losses in surface runoff by 79 and 86%, respectively, compared with broadcasting (17 Oct. 1998-27 Oct. 1999). Corresponding numbers for fecal coliforms were 350 CFU (100 mL)(-1) and for somatic coliphages were 110 PFU (100 mL)(-1) in surface runoff after injection in October 1998. Slurry injection should be favored when spreading slurry amendments to grassland to avoid losses of P and fecal microorganisms in runoff to surface waters.     

Ecotourism options in coastal protected area management: a case study of North Head Quarantine Station, Australia

The challenges faced by coastal protected areas in both promoting highly attractive sites and preserving the natural attributes of these sites have been given a new dimension with the opportunities presented by ecotourism. Realising the market potential of a protected area and, at the same time, conserving the unique features of an area is a difficult task. This paper explores the possibilities that backpacker tourism may offer the Quarantine Station in Sydney Harbour National Park, in Australia. The Quarantine Station is a significant cultural heritage site that is located in a sensitive coastal national park within Sydney's metropolitan area.     

Environmental Duty of Care: From Ethical Principle Towards a Code of Practice for the Grazing Industry in Queensland (Australia)

Among the options of government for reducing negative environmental externalities from agriculture is the institution of a polluter statutory liability. An environmental duty of care imposes a statutory liability on agents who interact with the environment to avoid causing environmental harm. This paper documents environmental duty of care provisions governing landholders in Queensland, Australia, with specific reference to the 2007 Queensland State Rural Leasehold Land Strategy. The paper reports on a positive response by a group of leaseholders within the Northern Gulf Region in Queensland who developed a prototype environmental code of practice for grazing—a land use not previously covered by such an institution in Australia. The paper concludes that (1) a statutory environmental duty of care and specific forms of leasehold tenure are elements of an effective strategy for implementing an agricultural environmental ethics in north Australia’s rangelands and (2) a grazing industry code of practice is a practical and important tool for the grazing industry to safeguard its social licence to operate.     

Impacts of nutrient additions and digging for human waste disposal in natural environments, Tasmania, Australia

Very little research has been undertaken on the impacts of human toilet waste disposal in non-serviced sites in the wild. The objective of the present project was to determine the relative impacts of the mechanical disturbance of digging during the burial of toilet waste (faeces and toilet paper), and urination, on Tasmanian vegetation types that occur in areas used for wild country camping, in order to develop appropriate guidelines. The mechanical disturbance of digging cat-holes 15 cm deep, typical of those used for toilet disposal in the Tasmanian wild, had largely negative effects on the growth of a few native plant species. These effects were of little or no conservation significance. The nutrient additions simulated by the addition of artificial urine to undug ground and dug ground had largely positive effects on nine distinct types of native vegetation, encouraging the growth of many plant species at many sites, while discouraging the growth of moss at one site. No weed species found at any of the sites were significantly affected by the treatments. Thus, it appears that scattered disposal of urine, even combined with digging, is unlikely to present a major conservation problem in the Tasmania's wild country, and that present guidelines are appropriate, where achievable.     

Riverbanks and the law: The arbitrary nature of river boundaries in New South Wales,Australia

Key aspects of environmental management exist within a legislative framework. The Rivers and Foreshores Improvement Act 1948 (NSW) and several Regional Environmental Plans created under the Environmental Planning and Assessment Act 1979 (NSW) make reference to ‘the top of the bank’ for defining areas of protected land adjacent to rivers, within which development consent may be required. It is an arbitrary term and its use within the Rivers and Foreshores Improvement Act 1948 (NSW) leads to confusion. This paper examines the range of definitions of ‘the top of the bank’ in respect of natural watercourses and aims to provide a more lucid and effective definition that will clarify existing ambiguities in legal interpretation. The paper examines the historical origins of the phrase ‘top of the bank’, finding that stereotyped Eurocentric views of what a river ‘should look like’ have impaired the legal definition for Australian rivers, thereby influencing common law and the development of statutory definitions. Judicial applications of the phrase ‘top of the bank’ are examined from a geomorphological perspective, demonstrating the misconceptions of the term in a legal context. The paper identifies the existence of widespread support for the need to protect land adjacent to rivers in the interests of environmental, economic and social sustainability. It concludes by calling for legislative reform that is both tailored to the individual site and consistent with overarching goals at the catchment scale.     

Evaluating the PM damage cost due to urban air pollution and vehicle emissions in Seoul, Korea

This study evaluated the prospective damage costs of PM(2.5) inhalation. We performed a health risk assessment based on an exposure-response function to estimate the annual population risk in the Seoul metropolitan city, Korea. Also, we estimated a willingness-to-pay (WTP) amount for reducing the mortality rate in order to evaluate a statistical life value. We combined the annual population risk and the value-of-statistical-life to calculate the damage cost estimate. In the health risk assessment, we applied the PM(2.5) relative risk to evaluate the annual population risk. We targeted an exposure population of 5,401,369 persons who were over the age of 30. Using a Monte-Carlo simulation for uncertainty analysis, we estimated that the population risk of PM(2.5) inhalation during a year in Seoul is 2181 premature deaths for acute exposure and 18,510 premature deaths for chronic exposure. The monthly average WTP for 5/1000 mortality reduction over ten years is $20.20 USD (95% C.I: $16.60-24.50) and the implied value-of-statistical-life (VSL) is $485,000 USD (95% C.I: $398,000-588,000). The damage cost estimate due to risk from PM(2.5) inhalation in Seoul is about $1057 million USD per year for acute exposure, and $8972 million USD per year for chronic exposure. It is important to note that this cost estimate does not reflect all health damage cost estimates in this urban area. This recommendation is a model for evaluating a mortality risk reduction and as such we must re-evaluate an integrated application of morbidity risk.     

Modeling wetland loss in coastal Louisiana: Geology,geography, and human modifications

Habitat change in coastal Louisiana from 1955/6 to 1978 was analyzed to determine the influence of geological and man-made changes on landscape patterns within 7.5 min quadrangle maps. Three quantitative analyses were used: principal components anlaysis, multiple regression analysis, and cluster analysis.Regional differences in land loss rates reflect variations in geology and the deltaic growth/decay cycles, man-induced chages in hydrology (principally canal dredging and spoil banking), and land-use changes (principally urbanization and agricultural expansion). The coastal zone is not homogeneous with respect to these variables and the interaction between causal factors leading to wetland loss is therefore locally variable and complex.The relationship between wetland loss, hydrologic changes, and geology can be described with statistically meaningful results, even though these data are insufficient to precisely quantify the relationship. However, these data support the hypothesis that the indirect impacts of man-induced changes (hydrologic and land use) may be as influential as the direct impacts resulting in converting wetlands to open water (canals) or modified (impounded) habitat.Three regions within the Louisiana coastal zone can be defined, based on the potential causal factors used in the analyses. The moderate (mean = 22%) wetland loss rates in region 1 are a result of relatively high canal density and developed area in marshes which overlie sediments of moderate age and depth; local geology acts, in this case, to lessen indirect impacts. On the other hand, wetland loss rates in region 2 are high (mean = 36%), despite fewer man-induced impacts; the potential for increased wetland loss due to both direct and indirect effects of man's activity in these areas is high. Conversely, wetland loss (mean = 20%) in region 3 is apparently least influenced by man's activity in the coastal zone because of sedimentary geology (old, thin sediments), even though these areas have already experienced significant direct habitat alteration and wetland loss.     

Evaluating geological sequestration of CO2 in bituminous coals: The southern Sydney Basin,Australia as a natural analogue

Carbon dioxide contents of coals in the Sydney Basin vary both aerially and stratigraphically. In places, the coal seam gas is almost pure CO₂ that was introduced from deep magmatic sources via faults and replaced pre-existing CH₄. In some respects this process is analogous to sequestration of anthropogenic CO₂. Laboratory studies indicate that CO₂:CH₄ storage capacity ratios for Sydney Basin coals are up to ∼2 and gas diffusivity is greater for CO₂ by a factor of up to 1.5.Present-day distribution of CO₂ in the coals is controlled by geological structure, depth and a combination of hydrostatic and capillary pressures. Under present-day P–T conditions, most of the CO₂ occurs in solution at depths greater than about 650 m; at shallower depths, larger volumes of CO₂ occur in gaseous form and as adsorbed molecules in the coal due to rapidly decreasing CO₂ solubility. The CO₂ has apparently migrated up to structural highs and is concentrated in anticlines and in up-dip sections of monoclines and sealing faults. CO₂ sequestered in coal measure sequences similar to those of the Sydney Basin may behave in a similar way and, in the long term, equilibrate according to the prevailing P–T conditions.In situ CO₂ contents of Sydney Basin coals range up to 20 m³/t. Comparisons of adsorption isotherm data measured on ground coal particles with in situ gas contents of Sydney Basin coals indicate that the volumes of CO₂ stored do not exceed ∼60% of the total CO₂ storage capacity. Therefore, the maximum CO₂ saturation that may be achieved during sequestration in analogous coals is likely to be considerably lower than the theoretical values indicated by adsorption isotherms.     

Modelling the impacts of strategic tree plantings on salt loads and flows in the Macquarie river catchment,NSW, Australia

In Australia, problems of dryland and stream salinity have recently become the focus of a National Action Plan. In many river catchments, preliminary stream salt load and salinity targets have been set to define maximum permissible export levels in 2015. Afforestation has been proposed as a strategy for meeting these targets, although several studies suggest that widespread commercial tree plantations are likely to deliver net dis-benefits. However, the impacts on stream salt loads of more localised tree plantings in high salt yielding areas have not been quantified. In this paper we use a simple empirical model to predict the effects of various strategic and non-strategic tree planting scenarios on flows and salt loads in the mid-Macquarie catchment, New South Wales. A simple salt routing model is then used to estimate the effect of these changes on salt loads at the end-of-valley monitoring site for the Macquarie catchment. Results suggest that widespread land management interventions will be required to meet the preliminary salt load targets for this catchment. On their own, small-scale, strategic tree planting in high salt export areas of the mid-Macquarie area will not have a significant impact on salt loads at the end-of-valley monitoring site. While widespread tree plantings may reduce salt loads in the longer term, they are likely to cause streamflow losses in the shorter term. Thus, stream salinities are expected to rise initially, due to the different response times of groundwater and surface water systems to land use change.     

Sources of water pollution and evolution of water quality in the Wuwei basin of Shiyang river, Northwest China

Based on surveys and chemical analyses, we performed a case study of the surface water and groundwater quality in the Wuwei basin, in order to understand the sources of water pollution and the evolution of water quality in Shiyang river. Concentrations of major chemical elements in the surface water were related to the distance downstream from the source of the river, with surface water in the upstream reaches of good quality, but the river from Wuwei city to the Hongya reservoir was seriously polluted, with a synthetic pollution index of 25. Groundwater quality was generally good in the piedmont with dominant bicarbonate and calcium ions, but salinity was high and nitrate pollution occurs in the northern part of the basin. Mineralization of the groundwater has changed rapidly during the past 20 years. There are 23 wastewater outlets that discharge a total of 22.4 x 10(6)m(3)y(-1) into the river from Wuwei city, which, combined with a reduction of inflow water, were found to be the major causes of water pollution. Development of fisheries in the Hongya reservoir since 2000 has also contributed to the pollution. The consumption of water must be decreased until it reaches the sustainable level permitted by the available resources in the whole basin, and discharge of wastes must also be drastically reduced.     

The Usefulness of a Threat and Disturbance Categorization Developed for Queensland Wetlands to Environmental Management,Monitoring, and Evaluation

There is no comprehensive system of describing threats and disturbances currently used in Australia, despite the widespread impacts of human activities on natural ecosystems. Yet a detailed categorization would facilitate the collation of threatening process information into information systems; enable standardized collection and availability of data; and enable comparative analyses of ecosystem condition between stakeholders, agencies, states, and nations, particularly for environmental reporting and evaluation mechanisms such as State of the Environment. As part of the Queensland Wetlands Programme (QWP), a threat and disturbance framework was developed, focused on the pressure and impacts components of the DPSIR (driver-pressure-state-impacts-response) framework. A wetland inventory database was developed also that included a detailed threat and disturbance categorization using the QWP framework. The categorization encompasses a broad range of anthropogenic and natural processes, and is hierarchical to accommodate varying levels of detail or knowledge. By incorporating detailed qualitative and quantitative information, a comprehensive threats and disturbances categorization can contribute to conceptual or spatially explicit knowledge and management assessments. The application of the framework and categorization to several threatening processes is demonstrated, and its relationship to current natural resource condition indicators is discussed. Threat evaluation is an essential component of ecological assessment and environmental management, and a standardized categorization enables consistency in attributing processes, impacts and their short- to long-term consequences. Such a systematic framework and categorization demonstrates the importance and usefulness of comprehensive approaches, and this approach can be readily adapted to management, monitoring and evaluation of other target ecosystems and biota.     

Procedures for ensuring community involvement in multijurisdictional river basins: a comparison of the Murray-Darling and Mekong river basins

Community involvement is fundamental to the management of multijurisdictional river basins but, in practice, is very difficult to achieve. The Murray-Darling basin, in Australia, and the Mekong River basin in Southeast Asia are both cooperatively managed multijurisdictional river basins where the management authorities have expressed an aim of community involvement. In the Murray-Darling basin vigorous efforts have promoted a culture of community consultation throughout each of the state jurisdictions involved, although true participation has not necessarily been achieved. In the Mekong basin the community is much more diverse and the successes so far have been largely at the local level, involving action in subsections of the basin. These case studies suggest that community involvement in the form of community consultation across large multijurisdictional river basins is achievable, but more comprehensive participation is not necessarily possible.     

Development and Adoption of a Simple Nonpoint Source Pollution Model for Port Phillip Bay,Australia

New computing tools and approaches allow tailored development of software to meet the needs of environmental managers. The processes required for such tailoring fit well with adaptive management concepts where, as knowledge and system understanding develop among managers, the software can be developed or replaced to match. This paper reports on development and adoption of a simple nonpoint source pollution modeling tool, including technical aspects of data support for modeling and social aspects of software design. The software, named FILTER, used a unit load model to generate expected pollutant loads from subcatchments of Port Phillip Bay, Australia. Monitoring data were used for calibration to modify the delivery of generated pollutants to receiving waters. Spatial, tabular, and charting software components were used to provide alternative forms of output visualization. FILTER was developed using a process that resulted in manager-stakeholders taking responsibility for setting of model parameter values and operation of the user interface, thereby encouraging uptake. The inclusive development process, tailoring of the software to manager needs and styles of usage, and matching of model complexity to data and knowledge, resulted in a successful application that has become the current agreed system representation among disparate stakeholder organizations.     

The history and evaluation of saltwater intrusion into a coastal aquifer in Mersin, Turkey

The Mersin-Kazanli region is a densely industrialized region. The factories and towns cover their water demand from groundwater. With the increased water demand, saltwater intrusion has occurred. The chloride concentration of the water samples from some wells has been analysed periodically since these wells were drilled. The results of these analyses and electrical conductivity measurements were used to show the history and development of saltwater intrusion up to the year 2000. The Cl(-) concentration of the water within the alluvial aquifer increased to over 3000 mg/l in 1999 and the wells were closed completely. In 2001 new wells were drilled more than 1 km away from the sea and old well field. With the results of the analyses conducted in 2001, the current groundwater quality was determined. The ground water is of the magnesium-calcium-bicarbonate type and this composition is controlled by the interaction of the water with the sediments of alluvial deposits.     

Distribution and mobility of mercury in soils of a gold mining region, Cuyuni river basin, Venezuela

An extensive and remote gold mining region located in the East of Venezuela has been studied with the aim of assessing the distribution and mobility of mercury in soil and the level of Hg pollution at artisanal gold mining sites. To do so, soils and pond sediments were sampled at sites not subject to anthropological influence, as well as in areas affected by gold mining activities. Total Hg in regionally distributed soils ranged between 0.02 mg kg(-1) and 0.40 mg kg(-1), with a median value of 0.11 mg kg(-1), which is slightly higher than soil Hg worldwide, possibly indicating long-term atmospheric input or more recent local atmospheric input, in addition to minor lithogenic sources. A reference Hg concentration of 0.33 mg kg(-1) is proposed for the detection of mining affected soils in this region. Critical total Hg concentrations were found in the surrounding soils of pollutant sources, such as milling-amalgamation sites, where soil Hg contents ranged from 0.16 mg kg(-1) to 542 mg kg(-1) with an average of 26.89 mg kg(-1), which also showed high levels of elemental Hg, but quite low soluble+exchangeable Hg fraction (0.02-4.90 mg kg(-1)), suggesting low Hg soil mobility and bioavailability, as confirmed by soil column leaching tests. The vertical distribution of Hg through the soil profiles, as well as variations in soil Hg contents with distance from the pollution source, and Hg in pond mining sediments were also analysed.     

Detecting the Dynamic Linkage between Landscape Characteristics and Water Quality in a Subtropical Coastal Watershed, Southeast China

Geospatial analysis and statistical analysis are coupled in this study to determine the dynamic linkage between landscape characteristics and water quality for the years 1996, 2002, and 2007 in a subtropical coastal watershed of Southeast China. The landscape characteristics include Percent of Built (%BL), Percent of Agriculture, Percent of Natural, Patch Density and Shannon’s Diversity Index (SHDI), with water quality expressed in terms of COD_Mn and NH₄ ⁺–N. The %BL was consistently positively correlated with NH₄ ⁺–N and COD_Mn at time three points. SHDI is significantly positively correlated with COD_Mn in 2002. The relationship between NH₄ ⁺–N, COD_Mn and landscape variables in the wet precipitation year 2007 is stronger, with R² = 0.892, than that in the dry precipitation years 1996 and 2002, which had R² values of 0.712 and 0.455, respectively. Two empirical regression models constructed in this study proved more suitable for predicting COD_Mn than for predicting NH₄ ⁺–N concentration in the unmonitored watersheds that do not have wastewater treatment plants. The calibrated regression equations have a better predictive ability over space within the wet precipitation year of 2007 than over time during the dry precipitation years from 1996 to 2002. Results show clearly that climatic variability influences the linkage of water quality-landscape characteristics and the fit of empirical regression models.