浙江大学学报(农业与生命科学版)
浙江大學學報(農業與生命科學版)
절강대학학보(농업여생명과학판)
2013年
3期
299-308
,共10页
李伟成*%王曙光%盛海燕%郑友苗%王树东%钟哲科
李偉成*%王曙光%盛海燕%鄭友苗%王樹東%鐘哲科
리위성*%왕서광%성해연%정우묘%왕수동%종철과
土壤温度%土壤水溶性有机碳含量%土壤含水量%半干旱区造林%竹林培育
土壤溫度%土壤水溶性有機碳含量%土壤含水量%半榦旱區造林%竹林培育
토양온도%토양수용성유궤탄함량%토양함수량%반간한구조림%죽림배육
soil temperature%soil water‐soluble organic carbon content%soil water content%afforestation in semi‐arid region%bamboo cultivation
以西南地区引种栽培的酒竹为对象,开展造林初期不同氮输入措施的试验以评价其对土壤呼吸的影响,并通过10 cm 深处土壤温度( soil temperature at 10 cm depth ,T10)、土壤水溶性有机碳含量( soil water‐soluble organic carbon content ,WSOC )和土壤含水量( soil water content ,SW)探讨其响应机制.结果显示:在不同氮输入处理下酒竹人工林T10、WSOC和SW的变化规律基本与土壤呼吸相似,全年呈现上升—高峰—下降—低谷的过程,雨季和旱季的差异性显著;土壤呼吸速率与 T10呈极显著相关的指数关系,而与WSOC、SW呈极显著相关的线性关系;全年温度敏感指数 Q10值在2.45~2.78之间,雨季的温度敏感性略低( Q10值在1.66~1.89之间),旱季则较为特殊,对温度敏感,Q10值在4.85~9.54之间,N80和N160处理降低了土壤呼吸的温度敏感性;测得的WSOC数据波动较大,酒竹人工林的氮输入并不能提高T10和SW ,但N80和N160相对提高了WSOC .SW和T10解释了全年在N0、N40、N80和N160处理下土壤呼吸变化的96.10%、94.30%、94.48%和92.99%,贡献了绝大部分信息量;雨季与旱季土壤呼吸的主导因素有所不同,雨季为SW ,旱季为T10.
以西南地區引種栽培的酒竹為對象,開展造林初期不同氮輸入措施的試驗以評價其對土壤呼吸的影響,併通過10 cm 深處土壤溫度( soil temperature at 10 cm depth ,T10)、土壤水溶性有機碳含量( soil water‐soluble organic carbon content ,WSOC )和土壤含水量( soil water content ,SW)探討其響應機製.結果顯示:在不同氮輸入處理下酒竹人工林T10、WSOC和SW的變化規律基本與土壤呼吸相似,全年呈現上升—高峰—下降—低穀的過程,雨季和旱季的差異性顯著;土壤呼吸速率與 T10呈極顯著相關的指數關繫,而與WSOC、SW呈極顯著相關的線性關繫;全年溫度敏感指數 Q10值在2.45~2.78之間,雨季的溫度敏感性略低( Q10值在1.66~1.89之間),旱季則較為特殊,對溫度敏感,Q10值在4.85~9.54之間,N80和N160處理降低瞭土壤呼吸的溫度敏感性;測得的WSOC數據波動較大,酒竹人工林的氮輸入併不能提高T10和SW ,但N80和N160相對提高瞭WSOC .SW和T10解釋瞭全年在N0、N40、N80和N160處理下土壤呼吸變化的96.10%、94.30%、94.48%和92.99%,貢獻瞭絕大部分信息量;雨季與旱季土壤呼吸的主導因素有所不同,雨季為SW ,旱季為T10.
이서남지구인충재배적주죽위대상,개전조림초기불동담수입조시적시험이평개기대토양호흡적영향,병통과10 cm 심처토양온도( soil temperature at 10 cm depth ,T10)、토양수용성유궤탄함량( soil water‐soluble organic carbon content ,WSOC )화토양함수량( soil water content ,SW)탐토기향응궤제.결과현시:재불동담수입처리하주죽인공림T10、WSOC화SW적변화규률기본여토양호흡상사,전년정현상승—고봉—하강—저곡적과정,우계화한계적차이성현저;토양호흡속솔여 T10정겁현저상관적지수관계,이여WSOC、SW정겁현저상관적선성관계;전년온도민감지수 Q10치재2.45~2.78지간,우계적온도민감성략저( Q10치재1.66~1.89지간),한계칙교위특수,대온도민감,Q10치재4.85~9.54지간,N80화N160처리강저료토양호흡적온도민감성;측득적WSOC수거파동교대,주죽인공림적담수입병불능제고T10화SW ,단N80화N160상대제고료WSOC .SW화T10해석료전년재N0、N40、N80화N160처리하토양호흡변화적96.10%、94.30%、94.48%화92.99%,공헌료절대부분신식량;우계여한계토양호흡적주도인소유소불동,우계위SW ,한계위T10.
Soil respiration is the primary way by which CO 2 absorbed by terrestrial plants returns to the atmosphere . And it may have distinctly dynamic patterns at different temporal scales since it is affected by diverse abiotic and biotic factors . Increasing deposition of nitrogen from the traditional cultivation of sympodial bamboos may lead to the sequestration of carbon in vegetation and soil . And the rising temperature and water content may increase the flux of CO2 from the soil , but the response of the ecosystem to simultaneous changes in all of these factors is still unknown . Meanwhile , to provide abundant supply of bamboo timber , afforestation of bamboo species such as Oxytenanthera braunii Pilger ap . Engler , Dendrocalamus brandisii Kurz and D . giganteus Munro is encouraged by the government but without scientific directions . And chemical fertilizers are usually applied into fields unscientifically and blindly in the villages of southwest China . Subsequently , what will happen to the soil structure and how to balance soil nutrient environment in the situation of chemical fertilizer abuse?
@@@@In the context of climate change , the amount of nitrogen allocated to the soil is predicted to increase with the productivity of terrestrial ecosystem , and may alter soil carbon storage capacities . To provide the proof of soil respiration responding to the nitrogen input for sympodial bamboo afforestation at the beginning period , we set up four nitrogen fertilization (CO( NH2 ) 2 ) levels in mid‐high mountain of southeast China , i .e . N content of 0 , 40 , 80 , 160 kg/hm2 (expressed on N0 , N40 , N80 , N160 , respectively) , using the two‐year old stump of wine bamboo which were planted every five meters . The soil respiration rate is measured by using trenching method and infrared gas analyzer . The responding mechanism is discussed through analyzing the change of soil temperature at 10 cm depth ( T10) , as well as changes of soil water‐soluble organic carbon content (WSOC) and soil water content (SW) .
@@@@Results showed that soil respiration rate was quite different between rainy and dry seasons . The soil respiration rate increased at the end of April or in the beginning of May when the rainy season arrived . Its wave crest arrived in July , Aug . and Sept . , and then the rate decreased along with the dry season in Nov . , Dec . , Feb . and Mar . , then the trough of soil respiration rate appeared . The variation rule of T 10 , WSOC and SW was similar as this way . Exponential function could be used to describe the relationship between T 10 and respiration rate . Meanwhile , WSOC and SW showed a linear relationship with the respiration rate respectively , and the regression test indicted that it was significant . And the temperature sensitivity value Q 10 of a whole year was 2 .45 2 .78 nearby . In rainy season , Q10 decreased to 1 .66 1 .89 , which indicated that the sensitivity of respiration rate responding to temperature decreased . On the contrary , Q10 ascended to 4 .85 9 .54 in dry season . The yearly data of WSOC were unstable , and the nitrogen input could not enhance T 10 and SW , but N80 and N160 could increase WSOC relatively . The changes of SW and T10 explained 96 .10% , 94 .30% , 94 .48% and 92 .99% of the variation of soil respiration rate in the treatment of N 0 , N40 , N80 and N160 , which contributed most of the information . The main factor affecting the soil respiration in rainy and dry seasons was quite different , which was SW and T 10 respectively .
@@@@As a consequence , the increase in ecosystem productivity may lead to an increase in carbon turnover in the soil , via an increase in the amount of biomass . But its process and mechanism involving different carbon pools are very complex , and to measure the soil respiration rate alone can not totally reflect the whole change of carbon cycle . Experiments of further control that involves different carbon pools interaction appending to the measurements of CO2 emission will help to clarify the relative importance of bulk soil and micro‐relationship in the prime effect .
