18 research outputs found
Modeling of Organic Matter Turnover in Some Taiwan Soils and Estimation of Criteria for the Application of Organic Manures
No full text本報告之目的是以台灣過去三處長期試驗資料，檢討不同環境及耕作制度下，連續施用一定量作物殘體或有機質肥料後，土壤中有機質的分解與累積的情形，並嘗試以一階反應方程式模擬之，以概括了解其長期趨勢，進而作為維持不同土壤有機質含量所需有機質肥料施用基準釐定之依據。討論之長期試驗資料包括台北每年二作水稻之48年試驗、屏東萬巒每年二作水稻和秋作大豆之14年試驗及台南善化每年二作或三作大豆之9年試驗等資料，並以日本埼玉縣鴻巢市每年一作水稻之60年試驗和神奈川縣平塚市寺田村每年洋蔥-甘藍各一作之9年試驗作為比較。結果顯示，溫帶較熱帶、水田較旱田，可維持較高的土壤有機質含量。化學肥料之長期施用較無肥區可維持較高的土壤有機質含量，而綠肥之長期施用，雖能使土壤有機質含量稍高於化肥區，但比之堆肥區則效果甚小。欲藉有機質肥料之施用，以提高有機質含量，台灣環境顯然較日本環境困難，旱田又較水田難。利用台灣地區有機質肥料在土壤中分解快速之事實，農地可利用作為無害有機廢棄物之處置場所，以達廢棄物減量之目的，但需按其分解特性，酌定合理施用量，以防二次污染。
根據試驗與模擬分析結果，台北水田在無肥狀態下以每作水稻收穫之殘株及根（約l.4Mg/ha/year）即可維持土壤有機質含量於3.5％水準，而欲使台北水田土壤有機質含量，由無肥區維持之3.5％提高至4.5%，每年需施用17Mg/ha（鮮重）廄肥，平衡時（約需70年），每年可釋出約180kg/ha氮量；在連用十年後，氮素礦化率即達85%，每年可釋出約150kg/ha氮量。善化旱田由l％提高到2%，每年需投入110Mg/ha蔗渣濾泥堆肥（鮮重），平衡時（約需30年）可釋出約740kg/ha氮量；在連用五年後，其礦化率已達90%，每年可釋出670kg/ha氮量，因此長期施用，恐有污染之虞。
This paper reviews changes of organic matter content in the soils of some long-term experiments conducted in Taiwan, where different rates of crops residues or organic manures had been applied continuously. The decompsition and accumulation of organic matter in the soils were simulated to the first order reaction and the model was used to estimate the input of organic manures required to maintain different levels of organic matter in the soils.
The experiments consist of a 48-year field trial with the cropping system of two crops paddy rice per year in Taipei, a 14-year field trial with the cropping system of rice-rice-soybean per year in Pingtung and a 9-year field trial with the cropping sy stem of 2-3 crops soybean per year in Taiwan. For the sake of comparison, a 60-year field trial with the cropping system of one crop paddy rice per year in Saitama, Japan and a 9-year field trial with the cropping system of onion-cabbage per year in Kanaga Wa, Japan were also reviewed.
The results indicate that soil organic matter can maintain higher generally in the Temperate than in the Tropics, and in paddy than in upland. The long-term application of chemical fertilizer did not deplete the content of soil organic matter but even increase slightly compared to the soil without application of fertilizers. A stablized content (3.0%) of organic matter was, in fact, maintained in the soil without application of fertilizer in this paddy soil; the rice stubbles and roots remained in the s oil after the harvests were enough to maintain this level of organic matter without any tendency of depletion. On the other hand, the long-term application of green manure did not increase the content of soil organic matter as significantly as that of comp ost did, although it did increase slightly higher than the soil with the application of chemical fertilizer. Apparently, the increase of soil organic matter through the application of organic manure is more difficult in Taiwan than in Japan due to its high er rate of decomposition. This characteristics, however, is advantageous for agricultural land to act as disposal places for the harmless organic waste produced by animal husbandry. The reasonable rate of application, however should be evaluated so that en vironmental impact will be minimized.
According to the results of the experiments and simulation analysis, the continuous application of 17Mg/ha/year (fresh weight basis) of farm yard manure for 70 years is required to raise soil organic matter from the level of 3.5% to 4.5%, both at nearly equilibrated state, in the paddy field of Taipei. The rate of N release at equilibrated status maintaining 4.5% organic matter is 180Kg N/ha/year. On the other hand, the continuous application of 110Mg/ha/year (fresh weight basis) of bagasse filter cake compost for 30 years 15 required to raise soil organic matter from the level of 1% to 2%, both at nearly equilibrated state, in the upland field of Tainan • The rate of N release at equilibrated state maintaining 2% organic matter is 740Kg N/ha/year. The 1ong-term application apparently will cause pollution to the environment
The relationship of initial soil organic matter and over decomposition phenomenon
No full textAn over decomposition phenomenon was discovered in the simulation process of soil organic matter decomposition. The over decomposition phenomenon presented the special hollow curve of soil organic matter accumulation which decreased temporally to the lower level than initial condition, then gradually increased to the final equilibrium level. The phenomenon usually happened when easily decomposed portion of initial soil organic carbon was great. This study discussed the relationship of initial soil organic matter and over decomposition phenomenon. The results of simulation process showed that: (1) The over decomposition could not be simulated by the mono-variable model, due to the partitioning of soil organic carbon could not be described by such a model. (2) According to the Jenkinson-Rayner model simulation, the phenomenon could easily occur when initial soil organic carbon contained great decomposable and resistant plant material. The change extent of curve was increased as the decomposable plant material portion was increased. (3) The phenomenon could never occur when the stabilized soil organic matter portion of initial soil organic carbon was great. (4) No matter how much organic matter was added, the phenomenon could never occur after soil organic carbon reached an equilibrium.
有機質的轉化過程長期以來一直是土壤研究者關心的重點。根據過去的硏究，發現一種土壤有機質總量自較高之初始狀態，會因後績之年度添加量不足以維持原有含量時，逐漸降解至一個低含量點，而後又漸漸累積，終至呈一新的穩定態之特 殊“過度分解”現象。此現象可能發生在初始狀態含較多易分解之物質。因此本文主耍爲探討模式變數設定及土壤有機質初始狀態與過度分解現象出現之相關性。
根據模式模擬結果顯示：(1)單變數模式因爲沒有土壤有機質形態之劃分，未能模擬過度分解現象。(2)若模擬初始之易分解態與抗分解態植物殘體佔土壤總有機碳 之絕大比例，將較易出現過度分解現象，且其變化幅度隨易分解態植物殘體在植物殘體中所佔之比例增加而變大。(3)若模擬 初始之穩定態有機質佔絕大部分，則不會出現過度分解現象。(4)當土壤有機碳達穏 定平衡後，無論添加多少量，都不會出現過度分解現象
部分農業區地下水氮和磷污染現況
No full textTo understand the current status of nitrogen and phosphorus contamination of groundwater resulting from fertilization on farmland, the history data from monitoring network by Water Resources Agency (WRA) and Environmental Protection Administration (EPA) have been analyzed and with groundwater quality on some agricultural regions sampled and measured. The results reveal quiet high percentages of monitoring wells set by WRA and EPA with NH4+-N contents in groundwater exceeding drinking water quality standard (0.1 mg/l), even higher than the limit of the second type groundwater pollution monitoring standard (0.25 mg/l). Based on the investigation of agricultural regions, the NH4+-N contamination from agricultural area seems similar as that from different land uses monitored by WRA or EPA. There are less 10 % of monitoring wells by WRA or EPA or sampled from agricultural regions of which NO3-N contents are higher than the limit of drinking water and exceeding the limit of drinking water quality standard (10 mg/l). However, no data higher than the limit of the second type groundwater pollution monitoring standard (25 mg/l) are observed. There is no significant correlation between the N content in groundwater and soil profile texture. However, the N contamination has been getting gradually higher on some agricultural region located in head recharge area of Choshui alluvial fan with few mud layers in the geological profile, even the soil texture is clay. One of the reasons might be attributed to heavy rate of fertilization by local farmers and need to be further confirmed in the future. The results also indicate almost the total P is much lower than limit of the groundwater quality standards (0.15 mg/l) stipulated by the Netherland
Model analysis for the transformation of carbon and nitrogen in
No full text土壤一作物系統中碳與氮動態的模式化，為不同土壤環境中碳與氮循
環，對環境影響評估之有利工具。本文根據長期與短期試驗，進行前人不
同土壤環境中碳轉化模式，對本土數據之模擬能力比較及模式之特性檢視
，在氮素轉化模擬，則選擇在台灣已經過多處作物生長方面測試之作物模
式 CERES-Maize中氮次模組，進行本土氮素轉化數據之模擬測試，嘗試藉
此模式解析、檢視與驗証工作，確立適宜之模擬機制，以為後續之研究與
應用，並作為未來建立一個適合於本土環境之模式之依據。根據模擬結果
，對於長期試驗土壤有機碳最終穩定趨向之模擬，無論簡單或複雜模式，
可藉參數之調整，使其結果相近，但就土地利用型態改變，所導致之過度
分解現象之可能性的預測，則必須擁有兩個變數以上之模式才適用。模式
驗証結果顯示， CERES-Maize模式中氮次模式可應用於壤土之一般耕作方
式與適量的施肥量下之模擬，唯在過高施肥量、氨揮散強及強淋洗量下模
擬準確性較差。封面
中文摘要
英文摘要(Abstract)
謝誌
次目
表次
圖次
第壹章、緒論
第一節、緣起
第二節、前人有關土壤環境中碳與氮轉化之相關研究
一、台灣地區歷年化學與有機質肥料施用情況與土壤有機質含量變化
二、台灣大宗有機質肥料生產量與成分
三、不同作物系統作物殘體回歸土壤量估算
四、土壤有機質之組成
五、土壤有機質碳與氮含量百分率
六、有機質肥料特性對其在土壤中分解之影響
七、土壤特性與環境對有機質分解與氮礦化釋出之影響
八、長期連用同種有機質肥料之試驗
九、土壤有機質達平衡之含量與所需時間
十、土壤有機質之年齡
十一、土壤有機質分解過程中之起應效果
十二、全球土壤有機質研究網與模式測試
十三、全球暖化對土壤CO?2釋出量之預測
十四、農田氮素循環之研究
十五、土壤氮轉化模擬模式
第貳章、土壤環境中碳、氮轉化模式之解析
第一節、土壤環境中碳轉化模式之理論解析
一、單變數一階反應式
二、雙變數一階反應式
三、Jenkinson-Rayner模式
四、Lin等(1987)模式
第二節、CERES-Maize中碳與氮轉化模式之理論解析
第三節、模式中分解速率常數之溫度與水分函數比較
第四節、結論
第參章、土壤環境中碳轉化模式之適用性分析
第一節、前言
第二節、材料與方法
一、檢視之模式說明
二、模式參數鑑定之試驗描述與說明
三、各模式對長期試驗中土壤有機碳轉化之模擬比較
四、各模式應用於模擬預測之適用性比較
五、單變數模式對於短期試驗資料之模擬
六、各模式對於土壤有機碳初期特殊分解動態模擬之檢視比較
第三節、結果與討論
一、不同試驗區土壤有機質分解與累積之比較
二、各模式對於長期試驗中土壤有機碳轉化之模擬比較
三、模式預測維持不同有機碳水準所需投入碳量之比較
四、單變數模式對於短期試驗資料之模擬
五、各模式對於土壤有機碳初期分解動態之模擬特性檢試與比較
第四節、結論
第肆章、土壤有機質降解過程之過度分解現象研究
第一節、前言
第二節、材料與方法
一、土壤有機質分解模式
二、由動態模式推導之平衡模式
三、過度分解現象之分析
四、靈敏度分析
第三節、結果與討論
一、模式動態模擬之平衡值與平衡模式計算之理論平衡值的比較
二、過度分解現象之分析
三、各參數及狀態變數起始值之相對靈敏度分析
第四節、結論
第伍章、CERRES-Maize中氮轉化次模式之驗証與檢討
第一節、前言
第二節、模式理論概述
第三節、材料與方法
一、模式驗証之試驗描述與說明
二、模式模擬作業
三、模式脫氮機制之靈敏度分析
四、新鮮有機物施用方式對脫氮影響之模擬分析
第四節、結果與討論
一、CERES-Maize中氮轉化次模式之驗証
二、模式脫氮機制之靈敏度分析
三、新鮮有機物施用方式對脫氮影響之模擬分析
第五節、結論
第陸章、總結
參考文獻
附錄
Impact Assessment of Shifts of Land Use on Soil Organic Carbon Storage of Cultivated land in Taiwan
No full textThis study is to evaluate the effect of the shifts of land use on soil organic carbon storage of cultivated land in Taiwan. The soil fertility survey data were used to evaluate soil organic carbon storage of cultivated land in Taiwan, and soil organic carbon contents were compared among different types of land use. On the base of soil survey data during 1978- 1982, the storage of soil organic carbon on the surface soil (0-20 cm) of cultivated land in Taiwan is 27.5 Tg, calculated by 850 thousand hectares of cultivated land in 1998, assuming that the majority of cultivated land has reached to equilibrium under the same long-term cultivation. This amount is 93 % of carbon released from energy source in 1990. The organic carbon storage of surface soil (0-20 公分)is about 30-40 % of the organic carbon storage to a depth of 100 cm. The survey data shows that paddy field obviously can accumulate more organic matter; therefore, the storage of surface soil (0-20 公分) organic carbon can be added 4.7 Tg if the current upland field is shifted to paddy field. But there is 5.5 Tg carbon released from soil if paddy field is shifted to upland field, showing that the surface soil (0-20 公分) organic carbon of cultivated land in Taiwan is between 22.0 to 32.2 Tg. According to the result of long-term experiments, the time for equilibrium on shifts of land use is 30 years. Nevertheless, the carbon amount stored or released by upland field shifted to paddy field or paddy field shifted to upland field is about 0.5 % and 0.6 % of carbon released from energy source.
本研究之目的係利用土壤肥力調查資料估算台灣農地土壤有機碳存量，並評估土地利用改變對農地土壤有機碳存量之影響，藉此評估土壤有機碳存量之變動量佔能源部門釋出碳量之百分比，以了解土壤有機碳之變動量對溫室氣體減量之重要性。依據1959-1967年間全省農田肥力測定所調查之78萬公頃耕地的土壤有機質分析結果，估算全省農地表土（0-20公分）的有機碳存量爲21.7 Tg (太克，1012g)，此碳量爲1990年能源部門釋出碳量(29.5 Tg)的74 %。若以1978-1982年間之調查資料爲基礎，又假設大部分已達平衡，以1998年的耕地面積85萬公頃，計算台灣農地土壤的表土（0-20公分）有機碳存量爲27.5 Tg，此碳量爲1990年能源部門釋出碳量(29.5 Tg)的93%。表土（0- 20公分）有機碳存量，約佔土壤一公尺深存量的30-40%左右。依調查資料顯示水田明顯可累積較多的有機質，因此若使現有的旱田轉作水田，則全省表土（0-20公分）有機碳存量可再增加4.7 Tg碳量，但若將水田轉作旱田則表土（0-20公分）有機碳可再釋出5.5 Tg之碳量，顯示台灣農地表土（0- 20公分）有機碳約在22.0-32.2 Tg之間。根據長期試驗結果顯示，土地利用改變所需的平衡時間約30年，因此，旱田轉作水田或水田轉作旱田，每年表土（0-20公分）所貯存或釋出的碳量，約是能源部門釋出碳量的0.5%與0.6%
Bound hydrocarbons and structure of pyrobitumen rapidly formed by asphaltene cracking: Implications for oil-source correlation
No full textThe pyrobitumen in conventional petroleum reservoirs is a thermally altered product of ancient oil pools, which may provide valuable source information using its molecular and isotopic signatures. Pyrobitumen formation is often associated with thermal alteration of asphaltene or polar-rich components rather than that of oil as a whole. Although asphaltenes are useful in source correlation of altered oils, the geochemical characteristics of asphaltene-derived pyrobitumen are poorly understood. In this study, artificial pyrobitumen formation through oil asphaltene cracking was performed at different thermal simulation (i.e., pyrolysis) temperatures. Systematic variations in the amounts and distributions of extractable and bound hydrocarbons, released by catalytic hydropyrolysis of the artificially produced pyrobitumen were studied. Pyrobitumen production yield was high at pyrolysis temperatures corresponding to post oil peak maturities, with a maximum yield of similar to 70 wt% of asphaltene being reached in the early condensate-wetgas stage. The molecular structure of pyrobitumen varied only slightly over the high maturity range (EasyRo 1.64-2.51%). Compared with the parent asphaltene, the pyrobitumen had a low biomarker (e.g., regular steranes and terpanes) content, and even the carbon isotopic values of the more stable bound n-alkanes were strongly altered. Thermal cracking of asphaltene alone, rather than whole oil, accelerates cross-linking of aromatic units, and cleavage or condensation of molecules bound in the pyrobitumen. These molecular changes suggest that care is needed when using the geochemical characteristics of bound hydrocarbons in natural pyrobitumen for source determinations. Nevertheless, the carbon isotopic ratios of bulk pyrobitumen hydropyrolysate were similar to those of bulk oil or pyrobitumen, even at very high maturities, suggesting these may be reliable indices for source tracing. A comparison of carbon isotopic compositions between pyrobitumen-bound and solvent-extractable n-alkanes could be useful in determining whether they have the same origin. Furthermore, the compositional and isotopic characteristics of bound hydrocarbons in pyrobitumen may provide information on the stage of maturity under geological conditions. The investigation of free and bound molecules may thus elucidate pyrobitumen genesis as related to its source, thermal maturity, and possible later hydrocarbon charging. (C) 2020 Elsevier Ltd. All rights reserved
(55(4):213-221)Effects of Organic and Chemical Fertilizers Suitable for Good Agricultural Practices on Root Yield and Active Ingredients of Boehmeria nivesa
No full text本試驗以每公頃施用(A)雞糞堆肥7,500 kg、(B)含木黴菌雞糞之生物性堆肥7,500 kg、(C)化學肥料(N 80kg٫ P2O5 20 kg٫ K2O 120 Kg)、(D) AR3-2S土壤添加物2,400 kg (N 3.9%，P2O5 2.23%，K2O 1.71%)及無肥對照區(CK)等五種處理參試，所用資材、土壤及水質的重金屬均控制在標準值之下，進行有機與化學肥料對苧麻根產量的影響，結果發現平均每公頃苧麻根之鮮重及乾重分別為A處理14,389 kg及5,568.5 kg；D處理16,486 kg及6,871 kg；C處理11,375 kg及4,449.8 kg；而B及CK處理均較低，分別各為10,056 kg及4,082.7 kg與8,597 kg及3,430.2 kg，但經綜合變方分析結果顯示，處理間均未達5%顯著差異水準◦分析各處理苧麻根之總三萜及總酚類含量變化發現，總三萜含量以A處理之雞糞堆肥區的0.38%最高，其次為B處理之木黴菌堆肥區0.237%次之，分別對其餘三處理達5%顯著差異水準；總酚類含量以不施肥區（對照組）為0.148%最高，含量稍高於施用含木黴菌生物性堆肥區（B處理）及雞糞堆肥區（B處理），且顯著高於C及D處理，達5%顯著差異水準◦The purpose of this study was to establish a model of good agricultural practices suitable for cultivation of Boehmeria nivesa in the field. The effects of different types of organic and chemical fertilizers on the root yield and active ingredients of this medicinal herb crop were evaluated. The concentrations of heavy metals and mineral elements in the tested organic and chemical fertilizers, and irrigation water were measured before planting. The control measures other than synthetic pesticides were used to manage the diseases and insect pests during plant growth stage. The treatments consisted of (A) chicken manure at 7,500 kg ha^(-1); (B) chicken manure with Tricoderma sp. at 7,500 kg ha^(-1); (C) chemical fertilizer at the rate of N:P2O5:K2O = 80: 20: 120 kg ha^(-1); (D) soil amendment (AR3-2S) with chemical fertilizer (N: P2O5: K2O = 3.9: 2.23: 1.71) at 2400 kg ha^(-1)and (E) non-treated plot used as the control (CK). Each treatment had four replicates in a randomized complete block design (RCBD). The results showed that there were no significant differences in root yield among treatments. The fresh and dry weight of root of B. nivesa were 14,389 kg and 5,568.5 kg in treatment A, 10,056 kg and 4,082.7 kg in treatment B, 11,375 kg and 4,449.8 kg in treatment C, 16,486 kg and 6,871.4 kg in treatment D, and 8,597 kg and 3,430.2 kg in CK, respectively. The triterpenes contents in roots harvested from treatment A and B were 0.38% and 0.237%, respectively, which were significantly (p=0.05) higher than other treatments. The content of total phenolic compounds in roots harvested from CK treatment was 0.148%, which was slight higher than A and B treatments, and significantly (p=0.05) higher than C and D treatments
Development of ICT for Leaching Monitoring in Taiwan Agricultural LTER Stations
No full textIn order to study the groundwater subsidy from different cropping systems, leaching monitoring in Taiwan started in 2008 and implemented agricultural long-term ecological research (LTER) stations. Initially, leaching data was received by lysimeters, and then collected manually by laborers in the field twice per month. The cost of data collection and transmission is high, real-time monitoring is not possible, and maintenance of instruments is inefficient. In this study, the goal is to develop a data transmission path. ICT (Information and Communication Technology) with different data transmission schemes was applied to improve the efficiency and immediacy of data transfer from the field to the databases in labs. Between 2010 and 2017, four versions of ICT have been developed and applied in LTER stations. WiFi, 2.5G (General Packet Radio Service, GPRS), 3G/4G network transmission, and Arduino cores are applied in different ICT versions. The first version of data transmission used data loggers, developed by the original factory, with a lower cost of renovation of instruments. However, complicated transmission paths, diverse instruments, poor weather resistance, and lack of wireless functionality are the limitations of the first version. Those limitations had been overcome by the second and third versions by using 2.5G (GPRS) and 3G/4G network transmission, respectively. Nevertheless, these versions are limited to the processes of data compression and encryption transmission which were developed by the system vendors. In addition, data can only be collected through the webpage provided by the vendors, instead of being received directly from the database using SQL (Structured Query Language). This is inappropriate for advanced data treatment, organization, and analysis. Finally, the fourth version of data transmission has been developed using Arduino. This system allows redesigning of the data loggers and transmission instrument with more feasibility and flexibility. Radio Frequency (Radio frequency, RF) has been imported into the transmission path to receive data from diverse instruments with fewer data loggers. In conclusion, ICT technological advancement with its advantages of reasonable cost and high flexibility and feasibility, Arduino and other open source operation systems can be used to develop the data loggers and related instruments to meet the needs of users. Therefore, ICT is the most appropriate strategy to develop the long-term monitoring system in the field and to apply to other environment monitoring systems
Composition and pore characteristics of black shales from the Ediacaran Lantian Formation in the Yangtze Block, South China
No full textThe Ediacaran period was critical in the evolution of the biosphere and ocean in the history of the Earth. Shales rich in organic matter (OM) are well developed for this period in the Yangtze Block, China, and have recently been related to shale gas exploration in South China. To date, detailed characterisation of the Ediacaran shales is not available. The present work sets out a detailed investigation of the composition and pore characteristics of samples from a shallow drill core in the Ediacaran Lantian Formation in the Lower Yangtze area, and the effects of shale composition on the pore growth are discussed.
The 90-m-thick Lantian black shales are highly over-mature (equivalent vitrinite reflectance (EVRo) value approximately 4.0%) with a total organic carbon (TOC) content up to 12%. They are dominated by quartz (33-72%), generally with low clay or feldspar content (<20%) and highly varied carbonate content (up to 60%). The Lantian shales are also notable for their high pyrite content (up to 19%), suggesting a depositional environment of an anoxic water body rich in sulphates; greatly enriched OM is facilitated in deep-water environments.
Bulk porosities of the shales range from 1.0% to 7.9%, and are positively correlated with TOC content. High-magnification scanning electron microscopy (SEM) images support the crucial importance of OM content on pore development. Generally, pore volume shows excellent, positive correlation with TOC content for micropores, good correlation for mesopores, and relatively poor correlation for macropores. Two samples with mostly high TOC content showed very low macropore volume and medium mesopore volume. These results suggest a close relationship between OM with relatively small pores, and enhanced compaction effect on large pores in highly OM-enriched shales. (C) 2016 Elsevier Ltd. All rights reserved
