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This special issue, entitled "Paleolimnology and Paleoecology in a Rapidly Changing Asia," was initiated during the third China Workshop on Lake Paleoecology that was held in Kunming, China, in December, 2019. Here, we summarize some of the key findings from the 10 papers that are included in this issue. The papers present sediment surveys of lakes from different parts of East Asia, and studies that spanned a variety of timescales, through multi-proxy analyses of modern samples, short cores and Holocene records. Overall, this special issue provides an up-to-date research snapshot in the fields of paleolimnology and paleoecology from rapidly changing regions of Asia, with a focus on the sediment signals of lake development, ecological shifts and anthropogenic forcing in the context of continuing climatic and societal changes. [ABSTRACT FROM AUTHOR]

The paper presents results of long-term (for seven years) monitoring and analysis of the formation of rainwater acidity in Primorsky Krai, southern Russian Far East. These results reveal the variability in the concentrations of both of total dissolved solids (TDS) and individual elements. Two groups of years were distinguished in the general dataset during which the character of the atmospheric circulation played an important role in the ionic balance of the rainwater. The study area was shown to be characterized by predominantly acidic precipitation, with the pH of the water rarely exceeding 5.3 even at low concentrations of strong acid anions. In order to identify the factors that form the acidity of rainwater, the paper proposes to rank the initial dataset according to the value of fractional acidity. In the course of this separation, data blocks with a high and low degree of neutralization of the acid potential are distinguished. Within each data block, the relationships between the pH value and the concentrations of the major ions are defined. During the analysis, it was found that the mechanism of acid rain generation is determined by the mutual influence of natural and human-made sources. It was shown that compounds of dissolved organic carbon (DOC) were involved in both acidification and neutralization of rainwater. The results obtained indicate the predominance of natural rain acidification factors. However, during periods of cyclonic activity, even a slight increase in anthropogenic load leads to an increase in the acidity of atmospheric precipitation to critical values. [ABSTRACT FROM AUTHOR]

The current paper tackles a critical question in climate change literature of whether farmers will be able to fully adapt to monsoonal climate changes owing to technological developments. Making use of the climate, agricultural and social data of Thailand from 1900 to 2015, this paper estimates a technological change instrumental variable by the growth of the normalized rice yield per hectare of land. The estimation shows that 0.98 of the growth in rice yield can be attributed to technological changes while the rest is accounted for by climate, soils and social factors. In the second stage regressions with the technological change indicator, the paper estimates the normalized numbers of the six most important types of live animals in Thailand: goats, chickens, cattle, sheep, pigs and buffaloes. Over the time period studied, the number of each of these live animals has increased vastly, except for buffaloes. The second-stage regressions show that the growth is largely attributable to technological changes, but monsoonal climate variables such as normalized monsoon precipitation ratio and normalized monsoon temperature are not significant factors. The results indicate that the rate of technological changes is overwhelming the rate of climate change on agriculture in Thailand. [ABSTRACT FROM AUTHOR]

Soil moisture (SM) is essential for sustaining services from Earth's critical zone, a thin-living skin spanning from the canopy to groundwater. In the Anthropocene epoch, intensive afforestation has remarkably contributed to global greening and certain service improvements, often at the cost of reduced SM. However, attributing the response of SM in deep soil to such human activities is a great challenge because of the scarcity of long-term observations. Here, we present a 37 y (1985 to 2021) analysis of SM dynamics at two scales across China's monsoon loess critical zone. Site-scale data indicate that land-use conversion from arable cropland to forest/grassland caused an 18% increase in SM deficit over 0 to 18 m depth (P < 0.01). Importantly, this SM deficit intensified over time, despite limited climate change influence. Across the Loess Plateau, SM storage in 0 to 10 m layer exhibited a significant decreasing trend from 1985 to 2021, with a turning point in 1999 when starting afforestation. Compared with SM storage before 1999, the relative contributions of climate change and afforestation to SM decline after 1999 were -8% and 108%, respectively. This emphasizes the pronounced impacts of intensifying land-use conversions as the principal catalyst of SM decline. Such a decline shifts 18% of total area into an at-risk status, mainly in the semiarid region, thereby threatening SM security. To mitigate this risk, future land management policies should acknowledge the crucial role of intensifying land-use conversions and their interplay with climate change. This is imperative to ensure SM security and sustain critical zone services. [ABSTRACT FROM AUTHOR]

This paper describes a new species of fossil wood, Wataria yunnanica Li et Oskolski, from the Dajie Formation of the middle Miocene in southern Yunnan province, China. This species shows the greatest similarity to the modern genus Reevesia Lindl. from the subfamily Helicteroideae of Malvaceae. The fossil specimen is ascribed to the genus Wataria Terada & Suzuki based on its combination of ring-porous wood and the presence of tile cells. It differs from other Wataria species because vessel groups are common in its latewood. This is the first record of Wataria in China. Other species of this genus have been reported from Oligocene and Miocene deposits in Japan, and from Miocene deposits in Korea. The occurrence of ring-porous wood in the Dajie Formation suggests that there may have been a seasonal (probably monsoonal) climate in southern Yunnan during the middle Miocene. [ABSTRACT FROM AUTHOR]

The vast Dongting Lake in the middle Yangtze River basin, China, was occupied by Chinese Neolithic settlements starting 10 000 years ago, and rice cultivation there is probably the earliest in the world. The numerous Neolithic settlements identified by previous archaeological surveys represent the five major Neolithic cultural stages, i.e. the Pengtoushan (9000–7900 cal. yr BP), Zaoshixiaceng (7900–6800 cal. yr BP), Daxi (6800–5500 cal. yr BP), Qujialing (5500–5000 cal. yr BP), and Shijiahe (5000–4000 cal. yr BP). Using sedimentological and geoarchaeological approaches, this paper analyses the drivers of basin-scale settlement relocation in relation to lake-level fluctuations and monsoon climate variations in the Holocene. The relocation of Neolithic sites around the lake shoreline and on the adjacent floodplain, together with radiocarbon-dated stratigraphy, clearly indicates that the shape of the lake basin was an incised and elongated valley occupied by a lake in the early Holocene, which became a broader and shallower depression in the mid to late Holocene. The established lowest habitable base of the settlements positioned on the lake shore assists reconstruction of the change in lake level from 22 m at 9000 cal. yr BP to 26 m at 5500–4000 cal. yr BP, although higher and lower lake levels occurred during the intervening cultural stages. The pollen spectra reveal a warming trend throughout the Holocene with at least four major temperature cycles, driven by monsoon variations between temperate- and warm-humid conditions. In the early Holocene the climate changed from cool-dry to warm-humid, and this played a key role in developing the earliest Pengtoushan culture in the region. Subsequent climate fluctuations fit well with the advance and retreat of the lake shore, also coevally with Neolithic site movements in the lake region. In this study we show how geoarchaeological evidence can be used in environmental reconstruction during the Holocene. [ABSTRACT FROM AUTHOR]

Aim This paper reviews the biogeography of the Australian monsoon tropical biome to highlight general patterns in the distribution of a range of organisms and their environmental correlates and evolutionary history, as well as to identify knowledge gaps. Location Northern Australia, Australian Monsoon Tropics (AMT). The AMT is defined by areas that receive more than 85% of rainfall between November and April. Methods Literature is summarized, including the origin of the monsoon climate, present-day environment, biota and habitat types, and phylogenetic and geographical relationships of selected organisms. Results Some species are widespread throughout the AMT while others are narrow-range endemics. Such contrasting distributions correspond to present-day climates, hydrologies (particularly floodplains), geological features (such as sandstone plateaux), fire regimes, and vegetation types (ranging from rain forest to savanna). Biogeographical and phylogenetic studies of terrestrial plants (e.g. eucalypts) and animals (vertebrates and invertebrates) suggest that distinct bioregions within the AMT reflect the aggregated effects of landscape and environmental history, although more research is required to determine and refine the boundaries of biogeographical zones within the AMT. Phylogenetic analyses of aquatic organisms (fishes and prawns) suggest histories of associations with drainage systems, dispersal barriers, links to New Guinea, and the existence of Lake Carpentaria, now submerged by the Gulf of Carpentaria. Complex adaptations to the landscape and climate in the AMT are illustrated by a number of species. Main conclusions The Australian monsoon is a component of a single global climate system, characterized by a dominant equator-spanning Hadley cell. Evidence of hot, seasonally moist climates dates back to the Late Eocene, implying that certain endemic elements of the AMT biota have a long history. Vicariant differentiation is inferred to have separated the Kimberley and Arnhem Land bioregions from Cape York Peninsula/northern Queensland. Such older patterns are overlaid by younger events, including dispersal from Southeast Asia, and range expansions and contractions. Future palaeoecological and phylogenetic investigations will illuminate the evolution of the AMT biome. Understanding the biogeography of the AMT is essential to provide a framework for ecological studies and the sustainable development of the region. [ABSTRACT FROM AUTHOR]

A riverbank filtration (RBF) system was installed in a rural village near the Kali River in southwestern India to evaluate its performance in attenuating total coliform bacteria and Escherichia coli loads in a monsoon-dominated climate in a developing country. A statistical analysis showed that RBF water was of higher microbial quality than other water sources in the study area. Based on the geometric mean of the data from the primary RBF well (MW3), the percent removal compared to the Kali River was 95.1% for total coliforms and 99.2% for £. coli. The maximum percent removals were 99.8% for total coliforms and 99.96% for E. coli. Bacteria concentrations were lower during the dry season than during the monsoon season when contaminants apparently infiltrated into the subsurface. The geometric mean of the annual removal efficiency translates to an approximately 1-log unit removal of E. coli per 26 m (≈75 ft) setback distance from the river. During the 1-year monitoring period, Indian water quality standards for total coliform bacteria were regularly exceeded, whereas £ coli standards were met for 29% of the dry season but only 7% of the monsoon season. The consistent problem of attaining local regulatory limits for bacteria show that, at this study site, (1) RBF needs to be considered a pre-treatment method and, (2) should be combined with conventional disinfection technology. Finally, although the bacteria data confirms that the setback distance of a RBF well from a river is an important factor determining the water quality, local conditions, such as influence of flood-irrigation of nearby rice paddies, presence of freely-roaming cattle and latrines, and outside defecation by residents, must be considered when establishing a RBF system in a monsoon climate in a developing country. [ABSTRACT FROM AUTHOR]

Abstract: Understanding of river systems that have experienced various forcing mechanisms such as climate, tectonics, sea level fluctuations and their linkages is a major concern for fluvial scientists. The 2525-km-long Ganga River derives its fluvial flux from northern part of the Indian subcontinent and drops in the Ganga–Brahmaputra delta and the Bengal fan regions. This paper presents a study of the Ganga River sediments for their textural properties, grainsize characteristics, and transportation dynamics. A suite of recently deposited sediments (189 bedload samples and 27 suspended load samples) of the river and its tributaries was collected from 63 locations. Dry and wet sieve methods of grainsize analysis were performed and Folk and Ward''s parameters were calculated. Transportation dynamics of the sediment load was assessed by means of channel hydrology, flow/sediment rating curves, bedform mechanics, grainsize images, and cumulative curves. Textural properties of the bedload sediments of the Ganga River tributaries originating from the Himalaya orogenic belt, the northern Indian craton and the Ganga alluvial plain regions are characterised by the predominance of fine to very fine sand, medium to fine sand, and very fine sand to clay, respectively. Downstream textural variations in the bedload and suspended load sediments of the Ganga River are, therefore, complex and are strongly influenced by lateral sediment inputs by the tributaries and channel slope. At the base of the Himalaya, a very sharp gravel–sand transition is present in which median grainsize of bedload sediments decreases from over −0.16 Φ to 2.46 Φ within a distance of 35 km. Downstream decline in mean grainsize of bedload sediments in the upper Ganga River within the alluvial plain can be expressed by an exponential formula as: mean grainsize (in Φ)=0.0024×Distance (in kilometres from the Himalayan front)+1.29. It is a result of selective transport phenomena rather than of abrasion, the condition attributed to channel competence with low gradient of 70 to 25 cm/km. Coarsening of the bedload sediments in the middle segment of the river develops due to the coarse bedload sediments (mean grainsize: 1.8–2.2 Φ) supply from the tributaries of the northern Indian craton region and increased unit stream power. The Ganga River sediments show a wide range of grainsize parameters [Bedload sediments: mean grainsize (1.5–3.8 Φ), standard deviation (0.3–0.7 Φ), skewness (−0.2–0.5), and kurtosis (0.8–2.4); suspended load sediments: mean grainsize (2.9–5.0 Φ), standard deviation (0.6–1.6 Φ), skewness (−0.6–0.4), and kurtosis (0.7–4.6)]. Mean grainsize of the bedload sediments is 2.6 Φ, which is 1.3 Φ units coarser than the suspended load sediments. The cumulative grainsize curves of the bedload sediments show a distinct “break” in slope, representing nearly 80% of the bedload sediment transported as graded suspension. During the peak monsoon discharge, most of the bedload sediments are transported as the discontinuous, fine sandy, graded suspension by the unidirectional unsteady shooting flow at a high transport rate (about 8×106 tons/d). A model of sedimentation transportation at river channel is proposed. The Ganga River mobilises a total of 729×106 tons of sediments annually through a narrow zone within its river valley. Under the present hydrogeological conditions, the river sedimentation is climatically controlled and is predicted to produce a 2000-km-long, 2- to 40-km-wide and 25- to 50-m-thick ribbon-shaped, well-sorted symmetrically skewed fine sand body. [Copyright &y& Elsevier]

Purpose: To identify the formation of meteopathic reactions in patients with respiratory diseases under the influence of extreme weather changes in Vladivostok. Methods: The short-term meteopathic reaction in patients with respiratory diseases to the impact of "Weather Complex", consisting of nine weather parameters, on the day of patient's examination and on 1 and 2 days before the examination, was assessed. 146 acclimatized residents of Vladivostok (29 patients with chronic bronchitis, 51 patients with controlled asthma, 39 patients with uncontrolled asthma and 27 healthy volunteers) were examined. Pulmonary function (PF) was studied by spirography and by body plethysmography. Results: The adaptive-compensatory response of PF in patients with respiratory diseases to weather decreases depending on the disease severity, resulting in the development of meteodependence. The impact of "Weather Complex" on a human body is primarily reflected in PF, and the reaction of metabolic parameters is manifested with a 1–2 days time lag. Glutathione peroxidase and glutathione reductase, key factors in maintaining oxidative cell balance, play the most important role in the formation of a compensatory response to weather. In the light of the global health implication, recommendations are suggested to adjust the treatment of patients with respiratory pathology in specific conditions of abruptly changeable weather. Conclusions: The maritime monsoon climate creates an additional strain on both respiratory system and systems that ensure the peroxidation balance worsening bronchopulmonary pathology. [ABSTRACT FROM AUTHOR]

The production of pasture in Ethiopia was simulated by means of a dynamic model. Most of the country is characterized by a tropical monsoon climate with mild temperatures and precipitation mainly concentrated in the June-September period (main rainy season). The production model is driven by solar radiation and takes into account limitations due to relocation, maintenance respiration, conversion to final dry matter, temperature, water stress, and nutrients availability. The model also considers the senescence of grassland which strongly limits the nutritional value of grasses for livestock. The simulation for the 1982-2009 period, performed on gridded daily time series of rainfall and maximum and minimum temperature with a resolution of 0.5°, provided results comparable with values reported in literature. Yearly mean yield in Ethiopia ranged between 1.8 metric ton per hectare (t ha-1) (2002) and 2.6 t ha−1 (1989) of dry matter with values above 2.5 t ha-1 attained in 1983, 1985, 1989, and 2008. The Ethiopian territory has been subdivided in 1494 cells and a frequency distribution of the per-cell yearly mean pasture production has been obtained. This distribution ranges from 0 to 7 t ha-1 and it shows a right skewed distribution and a modal class between 1.5-2 t ha-1. Simulation carried out on long time series for this peculiar tropical environment give rise to as lot of results relevant by the agroecological point of view on space variability of pasture production, main limiting factors (solar radiation, precipitation, temperature), and relevant meteo-climatic cycles affecting pasture production (seasonal and inter yearly variability, ENSO). These results are useful to establish an agro-ecological zoning of the Ethiopian territory. [ABSTRACT FROM AUTHOR]

Despite millions of dollars invested in soil and water conservation practices in the (sub) humid Ethiopian highlands and billions of hours of food-for-work farm labor, sediment concentration in rivers is increasing. This paper reports on the research to reverse the current trend. Based on the understanding of the hydrology of highlands, we provide evidence on sources of surface runoff and sediment and on mechanisms that govern the erosion processes and approaches and how they affect soil and water conservation practices. We suggest that priority in landscape interventions should be given to re-vegetation of the degraded areas so as to reduce the sediment concentration contributions originating from these areas. Additionally, efforts should be directed to gully rehabilitation in the saturated bottom landscape that may consist of vegetating shallow gullies and stabilizing head cuts of deeper gullies Finally, rehabilitation efforts should be directed to increase the rain water infiltration in the upland areas through the hard pan layer by connecting the land surface to the original deep flow paths that exist below about 60 cm. It will reduce the direct runoff during the rainy season and increase baseflow during the dry season.

Climate change has had a huge impact on Southwest China, where extreme weather events have taken on an increasing trend. The region lies in the transition zone of three monsoons (East Asian, Indian, and Tibetan Plateau). We analyzed long-term trends of drought and flood disasters using sequential data on China's drought and flood incidence over 500 years (1501-2000), as well as precipitation records from 45 weather stations during 1961-2010. Results show that both types of disaster became more frequent. During 1501-2000, drought frequency rose from 2.12 to 4.15 per century to 9.03 and flood frequency from 2.06 to 5.09 per century to 11.94. For the 10 decades during 1900-2000, droughts exhibited a significant increasing trend ( R = 0.4491), while floods showed a slight increasing trend ( R = 0.0346). For extreme floods and droughts in 1961-2010, precipitation records revealed that most (2/3) areas in the region had increasing drought or flood frequencies. Generally, both frequency and intensity of these weather hazards conspicuously increased in Southwest China during 1501-2000. [ABSTRACT FROM AUTHOR]

* Premise of the study: The paleogeographical origin of the relict North American Sequoia sempervirens is controversial. Fossil records indicate a Neogene origin for its foliage characteristics. Although several fossils from the Miocene sediments in eastern Asia have been considered to have close affinities with the modem S. sempervirens, they lack the typical features of a leafy twig bearing linear as well as scale leaves, and the fertile shoots terminating by a cone. The taxonomic status of these fossils has remained unclear. * Methods: New better-preserved fossils from the upper Miocene of China indicate a new species of Sequoia. This finding not only confirms the former presence of this genus in eastern Asia, but it also confirms the affinity of this Asian form to the modern relict S. sempervirens. * Key results: The principal foliage characteristics of S. sempervirens had already originated by the late Miocene. The eastern Asian records probably imply a Beringian biogeographic track of the ancestor of S. sempervirens in the early Neogene, at a time when the land bridge was not too cool for this thermophilic conifer to spread between Asia and North America. * Conclusions: The climatic context of the new fossil Sequoia in Southeast Yunnan, based on other floristic elements of the fossil assemblage in which it is found, is presumed to be warm and humid. Following the uplift of the Qinghai-Tibet Plateau, this warm, humid climate was replaced by the present monsoonal climate with dry winter and spring. This change may have led to the disappearance of this hygrophilous conifer from eastern Asia. [ABSTRACT FROM AUTHOR]

The mean temperature of the growing season has been found to correlate with treeline position across the globe, but regional variation still needs to be explained. In the present study, we explored how the elevation of the alpine treeline varies with slope exposure and the distinct influence of the summer monsoon in the Three Parallel Rivers region of SW China (Yunnan). We hypothesized that the treeline elevation will not vary distinctly with slope exposure, because tree canopies are coupled to atmospheric conditions rather than ground temperature. We extracted treeline positions from Landsat TM images, DEM (digital elevation model) data and climatic data from Worldclim to analyze the relationship between treeline position and climate. The results revealed no significant exposure effect. Treeline elevations were almost the same at different slope exposure in each of these north-south stretching mountain ranges. Counter to expectation, south-facing slopes showed a slightly lower position than the others, which may be caused either by greater monsoon exposure (cloud cover) or human disturbance. The mean growing season temperature at treeline showed the same pattern as was obtained globally in earlier assessments (6.7 °C). However, the treeline elevation (as well as the isotherm position) increased from west (wet) to east (drier) along the summer monsoon route. Our results confirmed the theory that the treeline is strongly associated with atmospheric circulation and does not benefit from greater radiative warming on south-facing slopes during the growing season. The common treeline isotherm hypothesis matches with treeline position in this monsoon-driven climate regime. [ABSTRACT FROM AUTHOR]

The article focuses on the study which presents a method to estimate runoff curve numbers (CNs) through the use of soil and water assessment tool (SWAT) model which is can take into account watershed heterogeneities such as climate conditions, land use and soil types in South Korea. The simulation flow data by SWAT is used by the proposed CN estimation method. The SWAT-based CN estimation method combined with the asymptotic CN method was used to the Chungju dam watershed in the country.

Degradation of soils by irrigation with ground waters containing residual alkalinity poses a major threat to agriculture in semi-arid regions, particularly in South Asia. However, there is a lack of indices to define the soil degradation and crop performance under a monsoon climate. Therefore, an experiment was conducted during 2000–2004 to determine the responses of paddy rice and wheat crops in rotation to irrigation with alkaline waters (AW) having similar salinity (electrolyte concentration 30 me L−1) but varying ionic constituents (sodium adsorption ratio irrigation water, SARiw 10 and 25; adjusted sodium adsorption ratio, adj.RNa 13.6 and 29.2; residual sodium carbonate, RSC 5 and 10 me L−1 and Cl:SO4 4:1 and 1:4, respectively). The concentration factors, ECe/ECiw (ratio of electrical conductivity of soil's saturation paste extract to that of the irrigation water) were between 1.1 and 1.8 for soils deprived of rainfall, whereas it was almost 1 for soils not sheltered from rain. Similarly, saturation paste extract, SARe, was between 1.6 and 2.0 times SARiw and 2.0–2.3 times SARiw with and without rainfall, and the exchangeable sodium per cent (ESP) 1.0–1.8 times SARiw. Yields of paddy relative to yields of crops irrigated with good-quality water, averaged 56–74% during the period 2000–2004 compared with 81–88% for wheat, indicating the greater sensitivity of rice to irrigation with AW. Elevated levels of sulphate rather than chloride in the irrigation water lessened the impacts of the residual alkalinity. Production functions showed that the sodicity (ESP) did not solely explain the variation in crop yields because the salinity stress simultaneously inhibited growth. None of the sodicity indices (RSC, SAR and adj.RNa) adequately defined the relative impacts of AW, although residual alkalinity (RSC) was a better indicator than either of the other two. The monsoon rains played an important role in alleviating the effects of residual alkalinity. Data presented here should support the development of more reliable criteria for the assessment of sodicity/salinity hazards from AW in semi-arid regions. [ABSTRACT FROM AUTHOR]

A one-year simulation of tide- andwind-driven circulation in the Java Sea, which is one ofthe Indonesian seas located in a tropical area, hasbeen carried out using a three-dimensionalhydrodynamic model incorporating the influence of thewind waves generated at the sea surface. This area isinfluenced by the monsoon climate (east- andwest-monsoon). Six hourly-wind fields at 10 m abovethe sea surface were used as a representative windfield. In other respects, the effect of waves on thethree-dimensional hydrodynamic model has beenrepresented by the surface and bottom stresses. Athird-generation wave model called WAM (WAMDI, 1988)was used to calculate the wave parameters and thewave dependence of the drag coefficient. Thetrajectory of water particles induced by thecalculated velocity fields in the Java Sea was then simulated.In dealing with hazardous phenomena, this modelwill be extended to predict suspended sediment fluxes,particularly those relating to catastrophic changes in seabottom topography and beach erosion. It is also animportant tool for the prediction of storm surge events. [ABSTRACT FROM AUTHOR]

Pan coefficients have been developed for the Sukhna lake region in Chandigarh, India that has a humid tropical monsoon climate, using the optimisation technique for annual, monthly and seasonal time scales. Evaporation estimated using the Bowen ratio energy budget method has been considered as actual evaporation. Results show that the pan coefficient for the study area varies significantly both by month and season. The month-wise variation is in the range of 0.72–1.40 and the seasonal variation is in the range of 0.81–1.16. Pan coefficients obtained using various existing models such as Cuenca, Snyder, Modified Snyder, Pereira, Orang, FAO-56 and Wahed–Snyder have also been compared with the developed coefficients. Comparative analysis indicates that the pan coefficients obtained using the Snyder model overestimate evaporation significantly, while the rest of the models significantly underestimate evaporation. The study concludes that the developed pan coefficients are observed to estimate the open-water surface evaporation with a fair degree of accuracy for the study area while the pan coefficient value of 0.7 being used by most field organisations in India give high errors. However, since pan coefficients vary spatially due to the variation in the relative significance of various meteorological parameters, the pan coefficients developed in the present study need to be further evaluated for their suitability to other similar climatic regions of India. [ABSTRACT FROM AUTHOR]

Despite increased attention to the need for sustainable agriculture, fertilizer application rates above crop requirements remain common agricultural practices in South Korea, causing eutrophication of freshwater and coastal ecosystems. The aim of this study is to quantify phosphorus (P) inputs, outputs, and retention in a forested-agricultural watershed. The P budget showed that the combined use of chemical fertilizer and organic compost was the largest source of P (97.6% of the total) followed by atmospheric wet deposition (2.1% of the total P), whereas forest export (0.2% of the total) and sewage treatment plants (STPs) (0.1% of the total) were negligible. The P outputs were crop harvesting and hydrologic export to surface water. The P balance showed that P inputs are higher than the P outputs; approximately 87% of the total P input was retained in the soils within the watershed. However, P concentrations in drainage water were still high enough to cause eutrophication of downstream reservoirs. The results provide important details on the proportion of P export and retention in the watershed. This will help efforts to improve water quality and design better management strategies for agricultural nonpoint source pollution. [ABSTRACT FROM AUTHOR]