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Rainwater harvesting,its prospects and challenges in the uplands of Talugtog,Nueva Ecija,Philippines

International Soil and water Conservation Research 2013年第3期1卷 56-67页

作者： Samuel M.Contreras Teresita S.Sandoval Silvino Q.Tejada bureau of soils of soils and water management the Philippines bureau of soils and water management the Philippines

The prospects and challenges facing eight small water impounding projects(SWIPs)in Talugtog,Nueva Ecija,an upland municipality located in Central Luzon,Philippines were evaluated using rapid appraisal and documentation of projects,interview of farmers and local officials,and a review of related studies undertaken on the same project *** challenges include the deterioration of structural facilities,inactive farmers associations,watershed degradation,and climate *** also aims to evaluate improvement and innovation in the future implementation of SWIPs as rainwater harvesting *** site was selected because it has the largest number of SWIPs established as one of the coping strategies during the 1997-1998 severe El *** of its location,it has no major irrigation systems and relies only on local rainwater storage *** study involves 8 SWIPs established in two clusters(i.e.,5 and 3 SWIPs in a watershed)as rainwater conservation and management *** indicated these clusters of SWIPs offer multiple benefits in terms of supplemental irrigation,inland fish production,and water for domestic purposes and livestock *** also serve as strategic small-scale upland structures that enhance recharging of groundwater,prevent flooding,and provide value-adding activities such as recreation,soil and water conservation,and environmental *** studies also identified their benefits at the farm and community levels as conserved rainwater through storage in SWIPs is translated into more economic ***,some SWIPs are confronted with various challenges;deterioration of structural facilities,inactive farmer associations,unabated watershed degradation,and threats of climate *** are seriously affecting the overall performance of *** actions should include the strengthening of small water impounding system associations(SWISA),repair and climate-proofing of structural facilities through the(SWISA

关键词： Rainwater harvesting Small water impounding project Upland watershed SWISA

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Dissolved organic carbon in permafrost regions: A review

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Science China Earth Sciences 2019年第2期62卷 349-364页

作者： Qiang MA Huijun JIN Congrong YU Victor F.BENSE State Key Laboratory of Frozen soils Engineering Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences School of Civil Engineering Harbin Institute of Technology State Key Laboratory of Hydrology-water Resources and Hydraulic Engineering Hohai University Hydrology and Quantitative water management Group Department of Environmental Sciences Wageningen University

A large quantity of organic carbon(C) is stored in northern and elevational permafrost regions. A portion of this large terrestrial organic C pool will be transferred by water into soil solution(～0.4 Pg C yr^(-1))(1 Pg=10^(15) g), rivers (～0.06 Pg C yr^(-1)),wetlands, lakes, and oceans. The lateral transport of dissolved organic carbon(DOC) is the primary pathway, impacting river biogeochemistry and ecosystems. However, climate warming will substantially alter the lateral C shifts in permafrost ***, permafrost, precipitation, soil humidity and temperature, and microbial activities, among many other environmental factors, will shift substantially under a warming climate. It remains uncertain as to what extent the lateral C cycle is responding,and will respond, to climate change. This paper reviews recent studies on terrestrial origins of DOC, biodegradability, transfer pathways, and modelling, and on how to forecast of DOC fluxes in permafrost regions under a warming climate, as well as the potential anthropogenic impacts on DOC in permafrost regions. It is concluded that:(1) surface organic layer, permafrost soils,and vegetation leachates are the main DOC sources, with about 4.72 Pg C DOC stored in the topsoil at depths of 0–1 m in permafrost regions;(2) in-stream DOC concentrations vary spatially and temporally to a relatively small extent (1–60 mg C L^(-1)) and annual export varies from 0.1–10 g C m^(-2) yr^(-1);(3) biodegradability of DOC from the thawing permafrost can be as high as 71%, with a median at 52%;(4) DOC flux is controlled by multiple factors, mainly including vegetation, soil properties,permafrost occurrence, river discharge and other related environmental factors, and(5) many statistical and process-based models have been developed, but model predictions are inconsistent with observational results largely dependent on the individual watershed characteristics and future discharge trends. Thus, it is still difficult to predict how futu

关键词： Dissolved organic carbon (DOC) Aquatic ecosystem Carbon biodegradability DOC export Permafrost degradation

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Development of Magnesium-Dominant soils Under Irrigated Agriculture in Southern Kazakhstan

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Pedosphere 2009年第3期19卷 331-343页

作者： A. KARIMOV M. QADIR A. NOBLE F. VYSHPOLSKY K. ANZELM International water management Institute (IWMI) Central Asia Regional Office Tashkent 700000 (Uzbekistan) International Center for Agricultural Research in the Dry Areas (ICARDA) Aleppo 5466 (Syria) International water management Institute (IWMI) Colombo 2075 (Sri Lanka) International water management Institute (IWMI) c/o WorldFish Center Penang 11960 (Malaysia) water Conservation Laboratory The Kazakh Research Institute of Water Management Ministry of Agriculture Taraz480022 (Kazakhstan) Southern Kazakhstan Hydrogeology and Land Reclamation Expedition Shymkent (Kazakhstan)

Irrational irrigation practices in the Arys Turkestan Canal command area in the southern part of Kazakhstan have led to the formation of soils with poor physical and chemical properties. To study whether irrigation and leaching practices and/or groundwater rise have contributed to the accumulation of Mg2+ on the cation exchange complex of these soils, historical changes in soil and groundwater quality were used as source data and the Visual MINTEQ model was applied to analyze the chemical composition of water and soils in the study area. The imposed irrigation regime and the leaching of light sierosem soils led to the dissolution and subsequent leaching of inherent gypsum and organic matter from the soil profile. Further, the domination of bicarbonate in the irrigation water promoted weathering of the carbonate minerals present as calcite. The higher concentrations of Mg2+ in comparison to Ca2+ in the irrigation water resulted in the replacement of Na+ by Mg2+ on the cation exchange complex. In the lower part of the command area, shallow groundwater has contributed to the accumulation of Na+ and to a large extent of Mg2+ on the cation exchange sites.

关键词： exchangeable magnesium high-magnesium soil and water Kazakhstan land degradation

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Fecal Enterococci Levels in Selected Tributaries of the Pampanga River Basin, Philippines, and Their Relation to Land Use

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Journal of Environmental Protection 2023年第1期14卷 32-49页

作者： Luis Angelo A. Cortez Maria Auxilia T. Siringan Edna D. Samar Lemnuel V. Aragones Institute of Environmental Science and Meteorology University of the Philippines Quezon City Philippines Soil and water Resources Research Division Bureau of Soils and Water Management Department of Agriculture Quezon City Philippines Microbiological Research and Services Laboratory University of the Philippines Natural Science Research Institute Quezon City Philippines

This study aims to generate data which can be used as a potential starting point for the updating of the Philippine water Quality Criteria and the determination of the true impact of land use to the fecal contamination of the Pampanga River Basin (PRB), the largest subwatershed of Manila Bay. Levels of fecal indicator bacteria (FIB) were determined in the selected tributaries of the PRB, representing three land use categories, namely, the forest/woodland (control), agricultural and residential lands. FIB were quantified in order to investigate the potential contribution of the selected areas in the fecal contamination of the PRB. The study was conducted in 2021 covering March, May, June, July, and September to represent the dry (March and May) and wet (June, July, and September) seasons. Counts of FIB, namely thermotolerant coliform, E. coli, and enterococci were qualitatively correlated with the results of the ocular survey and key informant interview based on known fecal contributors and their relevant rainfall data. FIB counts of water bodies in the selected agricultural and residential land use categories had Geometric Mean (GM) counts that are statistically greater than those of bodies of water near the representative forest/woodland (control), and exceeded the acceptable GM limits for all FIB, regardless of the season. Notably, the GM values recorded for the waters near the selected forest/woodland (control) passed the water quality criteria for all measured FIB parameters for both seasons. Furthermore, enterococci levels in the control site were statistically lower during the wet season. These initial findings suggest that agricultural and residential land use categories could be major contributors to the unacceptable water quality of tributaries of the Pampanga River Basin. The prevalence of thermotolerant coliforms and E. coli was noted regardless of rainfall and land use, indicating these FIB may not be adequate as water quality indicators. With their abil

关键词： Enterococci Thermotolerant Coliforms E. coli Geometric Mean Land Use

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Soil properties characterization for land-use planning and soil management in watersheds under family farming

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International Soil and water Conservation Research 2022年第1期10卷 119-128页

作者： Jose Miguel Reichert Paulo Ivonir Gubiani Danilo Rheinheimer dos Santos Dalvan Jose Reinert Celso Aita Sandro Jose Giacomini soils Department Universidade Federal de Santa Maria(UFSM)Santa MariaRSBrazil

Environmental monitoring of small,rural watersheds was one of the components of the Natural Re-sources management and Rural Poverty Alleviation Program(RS-Rural)in southern *** purpose of the monitoring was to assess the impact of promoting soil conservation and environment manage-ment practices adopted by farmers and funded by the *** four small monitored watersheds,in a total of 95 plots representing distinct land use and soil management,surface soil was collected to characterize ground-zero of the Program by determining several soil physical,chemical and microbio-logical *** component analysis(PCA)shows soil physical,chemical and biological properties were decisive in defining the agricultural soils in the rural watersheds with family *** sensitivity to chemical properties provides an opportunity to improve soil quality if soil management focuses on altering those *** management practiced by tobacco farmers leads to rapid,intense degradation of some natural soil properties,especially those related to the dynamics of soil organic matter,compared with more conservationist uses(forest,regrowth,and grassland).Thus,soil management must be reoriented to avoid the progress of degradation and recover soil physical and biological *** crops and by land-abandonment to allow natural vegetation are important management strategies for the degraded soils used for tobacco production,increasing soil organic matter,nutrients and microbial activity and thus allowing further crop *** conclusion,wa-tersheds with tobacco cropping have soils with lower quality than when under no-tillage grain pro-duction,requiring changes in land use and soil management.

关键词： Natural resources management Environmental monitoring Soil conservation Soil quality Alleviating poverty

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Growth Parameters of DK8031 Maize Variety as Affected by Varying Irrigation and Nitrogen Fertilizer Rates in Embu County, Kenya

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Journal of Environmental Science and Engineering(A) 2015年第8期4卷 432-444页

作者： Charles Nyambane Onyari Antony Mwangi Kibe Samuel Mwonga Department of Land and water management Embu University EMB U 6-60100 Kenya Department of Crops Horticulture and Soils Egerton University EGERTON 536 Kenya

Determination of crop growth parameters of maize helps assess the performance of the crop for food security. A study was conducted in two seasons covering 2012 and 2013 to establish optimal irrigation and nitrogen fertilizer rates for drought tolerant hybrid maize （Zea mays L.）, DK8031 variety, in sandy loam soils using furrow irrigation. Four additive irrigation levels （119.05 mm, 238.10 mm, 357.15 mm and 476.2 mm） were allocated the main plots while five nitrogen fertilizer rates （0 kg/ha, 60, 75 kg/ha, 90 kg/ha and 100 kg/ha） were allocated the sub-plots. Both irrigation and nitrogen fertilizer treatments significantly enhanced crop growth parameters under consideration. Stand count per treatment plot, plant height and number of leaves per ranged from 45-59 plants/plot, 215-238 cm and 14-16 leaves respectively. It was concluded that use of supplementary irrigation and phased nitrogen fertilizer rates for maize growing in areas such as Embu can greatly promote crop growth.

关键词： Maize irrigation nitrogen fertilizer rates plant height leaves per plant.

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Modeling habitat suitability of range plant species using random forest method in arid mountainous rangelands

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Journal of Mountain Science 2018年第10期15卷 2159-2171页

作者： Hossein PIRI SAHRAGARD Majid AJORLO Peyman KARAMI Range and watershed management Department Faculty of Soil and Water University of Zabol Department of Environmental Sciences Faculty of Natural Resources and Environment Sciences Malayer University

Mountainous rangelands play a pivotal role in providing forage resources for livestock, particularly in summer, and maintaining ecological balance. This study aimed to identify environmental variables affecting range plant species distribution, ecological analysis of the relationship between these variables and the distribution of plants, and to model and map the plant habitats suitability by the Random Forest Method(RFM) in rangelands of the Taftan Mountain, Sistan and Baluchestan Province, southeastern Iran. In order to determine the environmental variables and estimate the potential distribution of plant species, the presence points of plants were recorded by using systematic random sampling method(90 points of presence) and soils were sampled in 5 habitats by random method in 0–30 and 30–60 cm depths. The layers of environmental variables were prepared using the Kriging interpolation method and Geographic Information System facilities. The distribution of the plant habitats was finally modelled and mapped by the RFM. Continuous maps of the habitat suitability were converted to binary maps using Youden Index(?) in order to evaluate the accuracy of the RFM in estimation of the distribution of species potentialhabitat. Based on the values of the area under curve(AUC) statistics, accuracy of predictive models of all habitats was in good level. Investigating the agreement between the predicted map, generated by each model, and actual maps, generated from fieldmeasured data, of the plant habitats, was at a high level for all habitats, except for Amygdalus scoparia habitat. This study concluded that the RFM is a robust model to analyze the relationships between the distribution of plant species and environmental variables as well as to prepare potential distribution maps of plant habitats that are of higher priority for conservation on the local scale in arid mountainous rangelands.

关键词： Environmental (predictor) variables Habitat mapping Habitat distribution Random Forest Method Tartan Mountain

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Integrated soil, water and agronomic management effects on crop productivity and selected soil properties in Western Ethiopia

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International Soil and water Conservation Research 2018年第4期6卷 305-316页

作者： Teklu Erkossa Timothy O.Williams Fanuel Laekemariam International water management Institute P.O.Box 5689C/o ILRI Addis CampusAddis AbabaEthiopia Wolita University Ethiopia

Land degradation is a major challenge limiting crop production in Ethiopia. Integrated soil and water conservation is widely applied as a means to reverse the trend and increase productivity. This study investigated the effects of such integrated approaches at two sites, Jeldu and Diga, inWestern Ethiopia. A split plot design with physical soil and water conservation in the main plots and agronomic practices in the sub plots was employed. Maize (Zea mays L.) followed by groundnut (Arachis hypogaea L.) at Diga, and wheat (Triticum aestivum) followed by faba bean (Vicia faba L.) were the test crops. Surface soils were sampled before sowing and after the crop harvest, and analyzed for selected parameters. Soil moisture content during the growing period was also monitored. The use of soil bund increased soil moisture content, and significantly (P < 0.05) increased days to flowering and maturity, kernel weight and harvest index, grain yield of the test crops, with the exception of maize. The improved agronomic practices (intercropping, fertilization and row planting) significantly (P < 0.05) increased grain yield of all the test crops. The effect of the treatments on soil parameters may require longer time to be evident. Although the increase in crop yield due to soil bund and the improved agronomic practices is eminent, economic analysis is necessary before recommending the widespread use of the improved options.

关键词： Land degradation Soil bund Inter-cropping Improved crop varieties Crop-livestock systems

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Uncertainty analysis of runoff and sedimentation in a forested watershed using sequential uncertainty fitting method

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Research in Cold and Arid Regions 2016年第4期8卷 297-310页

作者： Tanveer Abbas Ghulam Nabi Muhammad W.Boota Fiaz Hussain Muhammad I.Azam HuiJun Jin Muhammad Faisal Centre of Excellence in water Resources Engineering University of Engineering and Technology Lahore State Key Laboratory of Frozen soils Engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

The Soil and water Assessment Tool （SWAT） was implemented in a small forested watershed of the Soan River Basin innorthern Pakistan through application of the sequential uncertainty fitting （SUFI-2） method to investigate the associateduncertainty in runoff and sediment load estimation. The model was calibrated for a 10-year period （1991–2000） with aninitial 4-year warm-up period （1987–1990）, and was validated for the subsequent 10-year period （2001–2010）. Themodel evaluation indices R2 （the coefficient of determination）, NS （the Nash-Sutcliffe efficiency）, and PBIAS （percentbias） for stream flows simulation indicated that there was a good agreement between the measured and simulated *** assess the uncertainty in the model outputs, p-factor （a 95% prediction uncertainty, 95PPU） and r-factors （averagewideness width of the 95PPU band divided by the standard deviation of the observed values） were taken into *** 95PPU band bracketed 72% of the observed data during the calibration and 67% during the validation. The r-factorwas 0.81 during the calibration and 0.68 during the validation. For monthly sediment yield, the model evaluation coefficients（R2 and NS） for the calibration were computed as 0.81 and 0.79, respectively; for validation, they were 0.78and 0.74, respectively. Meanwhile, the 95PPU covered more than 60% of the observed sediment data during calibrationand validation. Moreover, improved model prediction and parameter estimation were observed with the increasednumber of iterations. However, the model performance became worse after the fourth iterations due to an unreasonableparameter estimation. Overall results indicated the applicability of the SWAT model with moderate levels of uncertaintyduring the calibration and high levels during the validation. Thus, this calibrated SWAT model can be used for assessmentof water balance components, climate change studies, and land use management practices.

关键词： hydrological modeling uncertainty analysis SWAT model the Soan River Basin SUFI-2 method

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Engineering properties for high kitchen waste content municipal solid waste

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第6期7卷 646-658页

作者： Wu Gao Yunmin Chen Liangtong Zhan Xuecheng Bian MOE Key Laboratory of Soft soils and Geoenvironmental Engineering Institute of Civil EngineeringZhejiang University

Engineering properties of municipal solid waste （MSW） depend largely on the waste＇s initial compositionand degree of degradation. MSWs in developing countries usually have a high kitchen waste content（called HKWC MSW）. After comparing and analyzing the laboratory and field test results of physicalcomposition, hydraulic properties, gas generation and gas permeability, and mechanical properties forHKWC MSW and low kitchen waste content MSW （called LKWC MSW）, the following findings wereobtained：（1） HKWC MSW has a higher initial water content （IWC） than LKWC MSW, but the field capacitiesof decomposed HKWC and LKWC MSWs are similar; （2） the hydraulic conductivity and gaspermeability for HKWC MSW are both an order of magnitude smaller than those for LKWC MSW; （3）compared with LKWC MSW, HKWC MSW has a higher landfill gas （LFG） generation rate but a shorterduration and a lower potential capacity; （4） the primary compression feature for decomposed HKWCMSW is similar to that of decomposed LKWC MSW, but the compression induced by degradation ofHKWC MSW is greater than that of LKWC MSW; and （5） the shear strength of HKWC MSW changessignificantly with time and strain. Based on the differences of engineering properties between these twokinds of MSWs, the geo-environmental issues in HKWC MSW landfills were analyzed, including highleachate production, high leachate mounds, low LFG collection efficiency, large settlement and slopestability problem, and corresponding advice for the management and design of HKWC MSW landfills wasrecommended.

关键词： High kitchen waste content (HKWC) Municipal solid waste (MSW) Landfill Engineering properties Leachate MSW management

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