本文選題：集約經(jīng)營 + 雷竹林��； 參考：《浙江農(nóng)林大學》2017年碩士論文

【摘要】：森林是全球最大的陸地生態(tài)系統(tǒng),森林土壤是CO_2、CH_4、N_2O等溫室氣體重要排放源或吸收匯。集約經(jīng)營改變了森林土壤理化性質(zhì),影響了植物根系的生長和微生物的活性,導致森林土壤碳、氮循環(huán)發(fā)生改變進而影響土壤溫室氣體的排放。雷竹(Phyllostachys praecox)是我國優(yōu)良的筍用竹,廣泛分布于長江以南地區(qū),目前僅浙江省雷竹林面積就達6.7萬hm2,占全省經(jīng)濟林面積的7.7%。上世紀80年代以來,以施肥和覆蓋為核心的集約經(jīng)營措施提高了雷竹的經(jīng)濟效益,但同時導致土壤酸化、養(yǎng)分過量積累以及有機碳穩(wěn)定性下降等問題,目前雷竹林長期集約經(jīng)營過程中土壤溫室氣體排放的動態(tài)變化規(guī)律及其機理尚缺乏深入系統(tǒng)的研究。本研究利用空間代替時間的方法,以不同集約經(jīng)營時間(1、5、10、20和30年)雷竹林作為研究對象,利用靜態(tài)箱-氣相色譜法研究長期集約經(jīng)營過程中雷竹林土壤溫室氣體排放特征,結(jié)合土壤水溶性碳、氮和微生物生物量碳、氮的季節(jié)動態(tài)變化規(guī)律,探討長期集約經(jīng)營雷竹林土壤溫室氣體排放的動態(tài)變化機理,為科學評估經(jīng)營管理對土壤溫室氣體排放的影響提供科學支撐。研究結(jié)果如下:(1)隨集約經(jīng)營時間的增加,雷竹林表層土壤有機碳、全氮、堿解氮、有效磷、速效鉀含量均顯著提高(P0.05),土壤容重、土壤pH值顯著降低(P0.05)。雷竹林土壤水溶性有機碳(WSOC)、水溶性有機氮(WSON)、NH_4+-N、NO3--N、微生物生物量碳(MBC)和微生物生物量氮(MBN)含量均隨集約經(jīng)營時間的增加而增加(P0.05),MBC和MBN在集約經(jīng)營20年時達到最大值,隨后呈現(xiàn)降低趨勢。(2)雷竹林土壤CO_2排放通量呈明顯的季節(jié)變化,即春夏季高、秋冬季低。集約經(jīng)營1年、5年、10年、20年和30年雷竹林土壤CO_2年均排放通量分別為:338.89、337.53、374.52、491.10和364.14 mg·CO_2·m-2·h-1,在20年時達到最大值,隨后呈現(xiàn)降低趨勢。1年、5年、10年和30年雷竹林土壤CO_2年累積排放量沒有明顯差異。長期集約經(jīng)營顯著增加了20年雷竹林土壤CO_2年累積排放量(P0.05)。雷竹林土壤CO_2排放通量與地下5cm土壤溫度具有極顯著相關(guān)性(P0.01)。除集約經(jīng)營20年雷竹林外,其余集約經(jīng)營年份土壤CO_2排放通量均與WSOC呈顯著正相關(guān)(P0.05)。雷竹林土壤CO_2排放通量與土壤含水量、MBC沒有相關(guān)性。(3)雷竹林土壤N_2O排放通量具有明顯的季節(jié)變化,即春夏季高、秋冬季低。集約經(jīng)營1年、5年、10年、20年和30年雷竹林土壤N_2O年均排放通量分別為:54.10、155.19、202.34、246.53和315.17μg·N_2O·m-2·h-1。長期集約經(jīng)營顯著增加了雷竹林土壤N_2O年累積排放量(P0.05),具體表現(xiàn)為:集約經(jīng)營5年、10年、20年和30年雷竹林土壤N_2O年累積排放量分別是1年的3.07、3.48、4.00和5.74倍。集約經(jīng)營10年、20年和30年雷竹林土壤N_2O排放通量與地下5cm土壤溫度具有顯著相關(guān)性(P0.05)。集約經(jīng)營5年、10年和30年雷竹林土壤N_2O排放通量與土壤WSON具有顯著相關(guān)性(P0.05)。集約經(jīng)營10年和30年土壤N_2O排放通量與土壤NH_4+-N具有顯著相關(guān)性(P0.05)。土壤含水量、MBN、NO3--N與土壤N_2O排放通量沒有相關(guān)性。(4)雷竹林土壤CH_4排放通量沒有明顯的季節(jié)變化;集約經(jīng)營顯著增加了土壤CH_4年累積排放量(P0.05),并使土壤由CH_4吸收匯轉(zhuǎn)變?yōu)镃H_4排放源。集約經(jīng)營1年、5年、10年、20年和30年雷竹林土壤CH_4年累積排放量分別為:-0.05、2.89、3.28、6.22和0.80 kg·CH_4·hm-2·a-1。集約經(jīng)營5年土壤CH_4排放通量與地下5 cm土壤溫度具有顯著相關(guān)性(P0.05),其余集約經(jīng)營年份土壤CH_4排放通量與地下5 cm土層土壤溫度均無相關(guān)性。土壤CH_4排放通量與土壤含水量、WSOC、MBC均沒有相關(guān)性。(5)集約經(jīng)營1年、5年、10年、20年和30年雷竹林土壤排放溫室氣體的綜合溫室總效應分別為:30.15、33.99、37.19、45.52和39.18 Mg·CO_2-e·hm-2·a-1。集約經(jīng)營顯著增加了雷竹林土壤排放溫室氣體的綜合溫室效應,隨集約經(jīng)營時間的增加,雷竹林土壤排放溫室氣體的綜合溫室效應逐漸增加(P0.05),在集約經(jīng)營20年時達到最大值,隨后呈現(xiàn)降低趨勢。
[Abstract]:Forest is the largest terrestrial ecosystem in the world. Forest soil is an important source of greenhouse gases such as CO_2, CH_4 and N_2O. Intensive management has changed the physical and chemical properties of forest soil, influenced the growth of plant roots and the activity of microorganism, resulting in the change of carbon and nitrogen cycle in the forest soil and the influence of the emission of soil greenhouse gas. Bamboo (Phyllostachys praecox) is a fine bamboo shoot in China, which is widely distributed in the south of the Yangtze River. At present, the area of Lei Zhulin in Zhejiang province is 67 thousand Hm2, which accounts for the economic forest area of the province. Since 80s of the last century, the intensive management measures with fertilizer and cover as the core have improved the economic benefit of the bamboo, but at the same time it leads to soil acidification. The dynamic changes of soil greenhouse gas emissions in the long term intensive management of the bamboo forest and its mechanism are still lacking in deep systematic study. This study uses space instead of time to study the bamboo forest of different intensive management time (1,5,10,20 and 30 years). Object, using static box gas chromatography to study the characteristics of greenhouse gas emission from bamboo forest soil in long term intensive management, combined with the seasonal dynamic changes of soil water soluble carbon, nitrogen and microbial biomass carbon and nitrogen, to explore the dynamic change mechanism of greenhouse gas emission in long term intensive management of Lei bamboo forest, and to evaluate management management for scientific management. The research results are as follows: (1) with the increase of intensive management time, the soil organic carbon, total nitrogen, alkali hydrolysable nitrogen, available P, and available potassium in the surface soil of Lei bamboo forest increased significantly (P0.05), soil bulk density, soil pH value decreased significantly (P0.05). The water soluble organic carbon (WSOC) and water solubility in the soil of Lei bamboo forest The content of sexual organic nitrogen (WSON), NH_4+-N, NO3--N, microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) increased with the increase of intensive management time (P0.05). MBC and MBN reached the maximum at 20 years in intensive management, followed by a decreasing trend. (2) the CO_2 emission flux in the soil of Lei bamboo forests showed a significant seasonal change, namely, high in spring and summer, autumn and winter. Low season. Intensive management for 1 years, 5 years, 10 years, 20 years and 30 years of bamboo forest soil CO_2 annual discharge flux were 338.89337.53374.52491.10 and 364.14 mg. CO_2. M-2. H-1, reaching the maximum value at 20 years, followed by the decreasing trend.1 years, 5 years, 10 and 30 years, there was no significant difference between the cumulative emission of the soil of the bamboo forest soil in the year of 10 and 30. The battalion significantly increased the cumulative CO_2 annual CO_2 emission (P0.05) of the soil of the bamboo forest soil. There was a significant correlation between the CO_2 emission flux and the underground 5cm soil temperature (P0.01). In addition to the intensive management of the bamboo forest for 20 years, the soil CO_2 emission flux in the remaining intensive management years was significantly positively correlated with WSOC (P0.05). There is no correlation between MBC and soil water content. (3) the N_2O emission flux in soil of Lei bamboo forest has obvious seasonal changes, namely, high in spring and summer, low in autumn and winter, intensive management for 1 years, 5 years, 10 years, 20 years and 30 years in Lei Zhulin soil, respectively: 54.10155.19202.34246.53 and 315.17 mu g. N_2O. M-2. H-1. The cumulative N_2O annual emission (P0.05) of the soil of Lei bamboo forest was increased. The concrete performance was as follows: intensive management for 5 years, 10 years, 20 years and 30 years of bamboo forest soil N_2O cumulative emissions were 1 years 3.07,3.48,4.00 and 5.74 times respectively. Intensive management for 10 years, 20 and 30 years of bamboo forest soil N_2O flux and underground 5cm soil temperature has significant correlation (P0.05). Intensive management for 5 years, 10 years and 30 years of bamboo forest soil N_2O emission flux and soil WSON has significant correlation (P0.05). Intensive management for 10 years and 30 years of soil N_2O emission flux and soil NH_4+-N has significant correlation (P0.05). Soil water content, MBN, NO3--N and soil N_2O emission flux has no correlation. (4) CH_4 emission flux in the soil of Lei bamboo forest did not There were obvious seasonal changes; intensive management significantly increased soil CH_4 cumulative emission (P0.05) and changed soil from CH_4 absorption sink to CH_4 source. Intensive management for 1 years, 5 years, 10 years, 20 years and 30 years of Lei Zhulin soil cumulative emission were respectively -0.05,2.89,3.28,6.22 and 0.80 kg. CH_4. Hm-2 a-1. for 5 year soil CH. _4 emission flux has significant correlation with soil temperature of 5 cm underground (P0.05). There is no correlation between soil CH_4 emission flux and soil temperature in 5 cm soil layer in other intensive years. There is no correlation between soil CH_4 emission and soil water content, WSOC, MBC. (5) intensive operation for 1 years, 5 years, 10 years, 20 and 30 years of bamboo forest soil emission temperature. The overall effects of the integrated greenhouse gases are: 30.15,33.99,37.19,45.52 and 39.18 Mg. CO_2-e. Hm-2. A-1., which significantly increased the comprehensive greenhouse effect of the greenhouse gases emitted from the soil of the bamboo forest. With the increase of intensive management time, the greenhouse effect of the greenhouse gases from the bamboo forest soil increased gradually (P0.05) and in intensive management. The maximum was reached in 20 years, followed by a downward trend.
【學位授予單位】：浙江農(nóng)林大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：S795;S714

【參考文獻】

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