Wang L.X.,CAS Changchun Northeast Institute of Geography and Agroecology |
Ou Y.,CAS Changchun Northeast Institute of Geography and Agroecology |
Lv D.A.,CAS Changchun Northeast Institute of Geography and Agroecology |
Yan B.X.,CAS Changchun Northeast Institute of Geography and Agroecology |
And 4 more authors.
Process Safety and Environmental Protection
The improper disposal of boron waste (BW) would bring much trouble for environment, at the same time, BW with a higher content of boron (B) and magnesium (Mg) could be used as a fertilizer in B and Mg deficient soils. Therefore this study recommended a novel disposal method of BW by composting, and investigated the influence of BW additions (at rates of 2.5%, 5.0% and 7.5%, dry weight basis) on the bioavailability of B and Mg during aerobic swine manure composting. Results indicated that additions of BW increased the content of both B and Mg in different fractions. The proportion of B fractions in the final composted material supplemented with BW were: nonspecifically adsorbed B (NSA-B). >. B occluded in Mn oxyhydroxides (MOH-B). >. specifically adsorbed B (SPA-B). >. residual B (RES-B). >. B occluded in crystalline Fe and Al oxides (CRO-B). >. B occluded in amorphous Fe and Al oxides (AMO-B). The addition of BW improved the bioavailability of B to plants and reduced the proportion of Mg in the exchangeable fraction. Spearman correlation showed that B and Mg bioavailability was associated with fulvic acid (FA; P <. 0.05). This study suggested that the humification process changed bioavailable forms of B and Mg during co-composting. © 2016. Source
Li S.,CAS Wuhan Institute of Geodesy and Geophysics |
Li S.,University of Chinese Academy of Sciences |
Zhang L.,CAS Wuhan Institute of Geodesy and Geophysics |
du Y.,CAS Wuhan Institute of Geodesy and Geophysics |
And 4 more authors.
Environmental Modeling and Assessment
The identification of critical source areas (CSAs) and critical source periods (CSPs) are essential prerequisites for cost-effective practices of non-point source (NPS) pollution control. A simple empirical tool combining Export Coefficient Model (ECM) and a Geographic Information Systems (GIS)-based weighting scheme of watershed heterogeneity was proposed to estimate annual and monthly phosphorus loss, to identify critical source areas and periods, and to assess pollution control practices. The GIS-based weighting scheme was developed to represent the transport potential of runoff to move phosphorus from the land surfaces to waters, as a supplement to the source-based ECM. The empirical tool was applied to the Dianchi Lake watershed of China. The results showed that the total phosphorus loss from NPS in 2008 was 352.3 tons. The agricultural land was recognized as the largest and the most spatially various source type. The lakeside plain and the terraces of the watershed were identified as CSAs, which generated more than 90 % of non-point phosphorus. The early part of wet season (from May to August) was the CSPs, when about 70 % of non-point phosphorus was lost. The reduction of phosphorus fertilizers and the vegetated buffer strips (VBS) were effective in controlling phosphorus loss from NPS in the watershed. A reduction of 20 % in phosphorus fertilizer application combined with the set-up of VBS in both riparian area of the main watercourses and the lakeside areas would decrease 25 % of phosphorus loss. © 2016 Springer International Publishing Switzerland Source
Zhou Y.,Chinese Academy of Agricultural Sciences |
Zhou Y.,Key Laboratory of Nonpoint Source Pollution Control |
Zhou Q.B.,Chinese Academy of Agricultural Sciences |
Zhou X.Y.,Chinese Academy of Agricultural Sciences |
And 3 more authors.
Shengtai Xuebao/ Acta Ecologica Sinica
Agricultural ecological compensation is an important policy incentive method that is used to support and protect agriculture development. Research on the estimation and measurement methods of the compensation standard has continually been a focus within academic circles. The Contingent Valuation Method (CVM) is the preferred method and the most widely adopted method by the international community for non-market valuation. CVM is based on the theory of welfare economics with the characteristics of consumer utility consent, and uses the utility indexes of willingness to pay (WTP) and willingness to accept (WTA) to measure environmental items increase or decrease through survey experiments, and to assess the economic value of environmental services. Because CVM has been applied to the field of agricultural ecological compensation for a short time, and because of the weak quality of agriculture and the low level of farmers' cognition, the domestic real evidence studies of CVM are faced with many confusing issues. This study first clarified the scientific connotation and theoretical basis of CVM, and then fully and systematically examined the CVM research progress and representative cases in the field of agriculture compensation, both at home and abroad. The results showed that domestic research was still at the stage of theoretical explorations and pilot demonstration of policy projects. Therefore, there are large gaps in the economic assessment of regional agricultural development projects, and in providing the decision service for the agricultural environment and subsidy policies. The imaginary characteristic deviation, research technical means deviation, and the survey implementation deviation are discussed. These deviations existed in the application of CVM to evaluate the agricultural ecological compensation policy survey practice. This survey was conducted based on the willingness of farmers to adopt cleaner agricultural production technologies, provided by the researchers. This study then described reasonable technological approaches and countermeasures to avoid possible deviations, including establishing the hypothetical market close to real markets, clearing scope of measurement models, carrying out the validity and reliability inspection of CVM, and choosing two dimension evaluations and handling deviations in the investigation processes. This study analyzed the possible deviations and measures for the application of CVM in the field of agricultural ecological compensation, and the practical application was provided in two ways: (1) theoretical guidance to improve the accuracy and effectiveness for the compensation standard by CVM and (2) methods and ideas to surmount the application obstacles in agriculture ecological compensation policy in China. Therefore, this study has important practical significance and reference value. Finally, the inadequacy and limitations of the research were discussed, including: a lack of scientific analysis for the reasons of the deviation generation, a lack of empirical testing of the deviation processing method, and a lack of universal applicability of the solution. Therefore, in order to provide better services for government decision-making, the future study of CVM should apply improved and expanded research methods and contents. © 2015, Ecological Society of China. All rights reserved. Source
Fu B.,Yunnan Academy of Agricultural Sciences |
Liu H.,Chinese Academy of Agricultural Sciences |
Liu H.,Key Laboratory of Nonpoint Source Pollution Control |
Lu Y.,Yunnan Academy of Agricultural Sciences |
And 9 more authors.
Huanjing Kexue Xuebao/Acta Scientiae Circumstantiae
The runoff volume, nitrogen and phosphorus emission in the Fengyu River Watershed were calculated and the temporal changes of nitrogen and phosphorus were analyzed by using the continuous position monitoring data. It could provide the scientific evidences for the assessment of nitrogen and phosphorus emission, regulation of agricultural management and reduction of nitrogen and phosphorus pollution load in the Fengyu River Watershed. The results showed that the annual runoff volume of the Fengyu River Watershed was 0.99×109 m3. The runoff was concentrated in raining season (from July to September), accounted for 43.70%. The annual losses of total nitrogen (TN) and total phosphorus (TP) were 139.8 t and 27.7 t, respectively. Total dissolved nitrogen (DTN) and particulate phosphorus (PP) were separately the main forms of nitrogen and phosphorus emissions. The DTN accounted for 71.16% of TN and particulate nitrogen (PN) accounted for 28.84% of TN. The 76.47% of annual loss of TP was the PP, and total dissolved phosphorus (DTP) accounted for 23.53%. The losses of nitrogen and phosphorus in the raining season accounted for 55.33% and 77.81% for annual discharge, respectively. Rainfall was an important influencing factor for runoff process, and agricultural management also had a greater impact on runoff, and nitrogen and phosphorus losses. ©, 2015, Science Press. All right reserved. Source