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Spatio-temporal Characteristics of the Extreme Climate Events and Their Potential Effects on Crop Yield in Ethiopia

Journal of Resources and Ecology 2018年第3期9卷 290-301页

作者： SONG Shuai LI Fadong LU Yonglong Kifayatullah Khan XUE Jianfang LENG Peifang State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Department of Environmental and Conservation Sciences University of Swat Swat 19130 Pakistan

Extreme climate events exhibit an increasing spatio-temporal trend globally, and the increasing intensity and frequency may have severe impacts on the human society and natural ecosystems. This study analyzed the extreme temperature and precipitation variability from 1956 to 2016, and evaluated their potential effects on crop yield in Ethiopia. Relative extreme temperature indices exhibited a decreasing trend with low-temperature events, but a significantly upward trend with extreme high temperature events. The frequency of annual warm nights increased to a greater degree than that of cold days. The total annual wet-day precipitation decreased significantly at a rate of-46 mm/decade. Further, the succession of dry days gradually increased by 5.6 day/decade, while an opposite trend of wet days was found with a decline of 1.4 day/decade. The correlation between annual precipitation and crop production was 0.422, indicating that extreme precipitation indices may have higher explanatory power than extreme temperature indices in the crop yield variations. Moreover, the extreme climate changes have induced significant adverse impacts on crops yield particularly in Ethiopia where no proper adaptation measures have been implemented.

关键词： extreme climate crop yield trend analysis Ethiopia

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Remote Sensing Indices to Measure the Seasonal Dynamics of Photosynthesis in a Southern China Subtropical Evergreen Forest

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Journal of Resources and Ecology 2019年第2期10卷 112-126页

作者： SUN Leigang WANG Shaoqiang Robert A.MICKLER CHEN Jinghua YU Quanzhou QIAN Zhaohui ZHOU Guoyi MENG Ze Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Hebei Engineering Research Center for Geographic Information Application Institute of Geographical SciencesHebei Academy of SciencesShijiazhuang 050011China School of Geography and Information Engineering China University of GeosciencesWuhan 430074China Department of Forestry and Environmental Resources North Carolina State UniversityRaleighNorth CarolinaUSA School of Environment and Planning Liaocheng UniversityLiaochengShandong 252059China South China Botanical Garden Chinese Academy of SciencesGuangzhou 510650China

The accurate measurement of the dynamics of photosynthesis in China’s subtropical evergreen forest ecosystems is an important contribution to carbon(C) sink estimates in global terrestrial ecosystems and their responses to climate change. Eddy covariance has historically been the only direct method to assess C flux of whole ecosystems with high temporal resolution, but it suffers from limited spatial resolution. During the last decade, continuous global monitoring of plant primary productivity from spectroradiometer sensors on flux towers and satellites has extended the temporal and spatial coverage of C flux observations. In this study, we evaluated the performance of two physiological remote sensing indices, fluorescence reflectance index(FRI) and photochemical reflectance index(PRI), to measure the seasonal variations of photosynthesis in a subtropical evergreen forest ecosystem using continuous canopy spectral and flux measurements in the Dinghushan Nature Reserve in southern *** more commonly used NDVI has been shown to be saturated and mainly affected by illumination(R^2=0.88, p <0.001), but FRI and PRI could better track the seasonal dynamics of plant photosynthetic functioning by comparison and are less affected by illumination(R^2=0.13 and R^2=0.51, respectively) at the seasonal scale. FRI correlated better with daily gross primary production(GPP) in the morning hours than in the afternoon hours, in contrast to PRI which correlated better with light-use efficiency(LUE) in the afternoon hours. Both FRI and PRI could show greater correlations with GPP and LUE respectively in the senescence season than in the recovery-growth season. When incident PAR was taken into account, the relationship between GPP and FRI was improved and the correlation coefficient increased from 0.22 to 0.69(p < 0.001). The strength of the correlation increased significantly in the senescence season(R^2=0.79, p < 0.001). Our results demonstrate the application of FRI and PRI as ph

关键词： fluorescence reflectance index(FRI) photochemical reflectance index(PRI) photosynthesis gross primary productivity(GPP) light-use efficiency(LUE) subtropical evergreen forest

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VHR GeoEye-1 imagery reveals an ancient water landscape at the Longcheng site,northern Chaohu Lake Basin(China)

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International Journal of Digital Earth 2017年第2期10卷 139-154页

作者： Lei Luo Xinyuan Wang Jie Liu Huadong Guo Xin Zong Wei Ji Hui Cao Key Laboratory of Digital Earth Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijingPeople’s Republic of China Institute of Remote Sensing and Digital Earth University of Chinese Academy of SciencesBeijingPeople’s Republic of China International Centre on Space Technologies for Natural and Cultural Heritage BeijingPeople’s Republic of China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingPeople’s Republic of China

This study mainly focuses on revealing an ancient water landscape at the Longcheng site in the northern Chaohu Lake Basin using very highresolution(VHR)GeoEye-1 ***,prior to classification,the GeoEye-1 image was processed following atmospheric and geometric *** supervised classification was carried out in order to show the land-cover situation in the Longcheng *** overall classification accuracy was 89.98%,with a kappa coefficient of *** moat system around the city walls was discovered by using rule-based objectoriented segmentation of the postclassified image,and the other walls of ancient Longcheng were manually identified from the pansharpened VHR GeoEye-1 ***,a map of the ancient water landscape containing the ancient city,wall and moat at the Longcheng site was *** paper demonstrates that VHR remote sensing has the ability to uncover an ancient water landscape and provide new insights for archaeological and paleoenvironmental studies.

关键词： VHR remote sensing archaeological classification segmentation GeoEye-1 Longcheng

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Carbon sequestration potential and its eco-service function in the karst area, China

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Journal of Geographical Sciences 2017年第8期27卷 967-980页

作者： SONG Xianwei GAO Yang WEN Xuefa GUO Dali YU Guirui HE Nianpeng ZHANG Jinzhong College of Resources and Environment Southwest University Chongqing 400716 China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

The karst critical zone is an essential component of the carbon （C） pool, constituting the global C cycle. It is referred to as one of the ＂residual land sink＂ that remains largely in- determinate. Karst area （2.2×10^7 km^2） comprises 15% of the world＇s land area, and karst area comprises 3.44~106 km^2 of area in China. Due to the complexity of karst structure and its considerable heterogeneity, C sequestration rate estimations contain large inaccuracies, especially in relation to the different methods used in calculations. Therefore, we reevaluated rock weathering-related C sink estimations in China （approximately 4.74 Tg C yr^-1）, which we calibrated from previous studies. Additionally, we stipulated that more comprehensive re- search on rock-soil-biology-atmosphere continuum C migration is essential to better under- stand C conversion mechanisms based on uncertainty analyses of C sink estimations. Moreover, we stressed that a collective confirmation of chemical methods and simulated models through a combined research effort could at least partially eliminate such uncertainty. Furthermore, integrated C cycling research need a long-term observation of the carbon flux of multi-interfaces. The enhanced capacity of ecosystem C and soil C pools remains an effective way of increasing C sink. Karst ecosystem health and security is crucial to human social de- velopment, accordingly, it is critical that we understand thresholds or potential C sink capacities in karst critical zones now and in the future.

关键词： karst karst critical zone carbon sink carbon sequestration rate China

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Nitrogen mobility,ammonia volatilization,and estimated leaching loss from long-term manure incorporation in red soil

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Journal of Integrative Agriculture 2017年第9期16卷 2082-2092页

作者： HUANG Jing DUAN Ying-hua XU Ming-gang ZHAI Li-mei ZHANG Xu-bo WANG Bo-ren ZHANG Yang-zhu GAO Su-duan SUN Nan College of Resources and Environment Hunan Agricultural UniversityChangsha 410128P.R.China Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences(CAAS)/National Engineering Laboratory for Improving Quality of Arable LandBeijing 100081P.R.China Red Soil Experimental Station of CAAS in Hengyang/National Observation and Research Station of Farmland Ecosystem in Qiyang Qiyang 426182P.R.China Key Laboratory of Ecosystem Network Observation and Modeling/Yucheng Comprehensive Experiment Station Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101P.R.China USDA Agricultural Research Service San Joaquin Valley Agricultural Sciences CenterCA 93648-9757USA

Nitrogen（N） loss from fertilization in agricultural fields has an unavoidable negative impact on the environment and a better understanding of the major pathways can assist in developing the best management practices. The aim of this study was to evaluate the fate of N fertilizers applied to acidic red soil（Ferralic Cambisol） after 19 years of mineral（synthetic） and manure fertilizer treatments under a cropping system with wheat-maize rotations. Five field treatments were examined： control（CK）, chemical nitrogen and potash fertilizer（NK）, chemical nitrogen and phosphorus fertilizer（NP）, chemical nitrogen, phosphorus and potash fertilizer（NPK） and the NPK with manure（NPKM, 70% N from manure）. Based on the soil total N storage change in 0–100 cm depth, ammonia（NH_3） volatilization, nitrous oxide（N_2O） emission, N plant uptake, and the potential N leaching loss were estimated using a mass balance approach. In contrast to the NPKM, all mineral fertilizer treatments（NK, NP and NPK） showed increased nitrate（NO_3~–） concentration with increasing soil depth, indicating higher leaching potential. However, total NH_3 volatilization loss was much higher in the NPKM（19.7%） than other mineral fertilizer treatments（≤4.2%）. The N_2O emissions were generally low（0.2–0.9%, the highest from the NPKM）. Total gaseous loss accounted for 1.7, 3.3, 5.1, and 21.9% for NK, NP, NPK, and NPKM treatments, respectively. Estimated N leaching loss from the NPKM was only about 5% of the losses from mineral fertilizer treatments. All data demonstrated that manure incorporation improved soil productivity, increased yield, and reduced potential leaching, but with significantly higher NH_3 volatilization, which could be reduced by improving the application method. This study confirms that manure incorporationis an essential strategy in N fertilization management in upland red soil cropping system.

关键词： soil NO_3~–-N ammonia volatilization nitrogen leaching long-term field experiment mass balance nitrous oxide emission

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Climatic and geographic factors affect ecosystem multifunctionality through biodiversity in the Tibetan alpine grasslands

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Journal of Mountain Science 2017年第8期14卷 1604-1614页

作者： PAN Ying WU Jun-xi LUO Li-ming TU Yan-li YU Cheng-qun ZHANG Xian-zhou MIAO Yan-jun ZHAO Yan YANG Jun-ling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Key Laboratory of Ecosystem Network Observation and Modelling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences Agricultural Research Institute Tibet Academy of Agricultural and Animal Sciences Tibet Plateau Institute of Biology Agricultural and Animal Husbandry College of Tibet University

ecosystem multifunctionality(EMF), the simultaneous provision of multiple ecosystem functions, is often affected by biodiversity and environmental factors. We know little about how the interactions between biodiversity and environmental factors affect EMF. In this case study, a structural equation model was used to clarify climatic and geographic pathways that affect EMF by varying biodiversity in the Tibetan alpine grasslands. In addition to services related to carbon, nitrogen, and water cycling, forage supply, which is related to plantproductivity and palatability, was included in the EMF index. The results showed that 72% of the variation in EMF could be explained by biodiversity and other environmental factors. The ratio of palatable richness to all species richness explained 8.3% of the EMF variation. We found that air temperature, elevation, and latitude all affected EMF, but in different ways. Air temperature and elevation impacted the aboveground parts of the ecosystem, which included plant height, aboveground biomass, richness of palatable species, and ratio of palatable richness to all species richness. Latitude affected EMF by varying both aboveground and belowground parts of the ecosystem, which included palatable speciesrichness and belowground biomass. Our results indicated that there are still uncertainties in the biodiversity–EMF relationships related to the variable components of EMF, and climatic and geographic factors. Clarification of pathways that affect EMF using structural equation modeling techniques could elucidate the mechanisms by which environmental changes affect EMF.

关键词： Alpine grassland Biodiversity Structural equation model Tibetan Plateau

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ecosystem Carbon Allocation of a Temperate Mixed Forest and a Subtropical Evergreen Forest in China

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Journal of Resources and Ecology 2018年第6期9卷 642-652页

作者： LUO Yiwei ZHANG Leiming GUO Xuebing DAI Guanhua WANG Anzhi ZHOU Guoyi YU Guirui Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing I00101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016China South China Botanical Garden Chinese Academy of SciencesGuangzhou 510650China

ecosystem carbon allocation can indicate ecosystem carbon cycling visually through its quantification within different carbon pools and carbon *** the ecological inventory and eddy covariance measurement applied to both a mature temperate mixed forest in Changbai Mountain (CBM)and a mature subtropical evergreen forest in Dinghu Mountain (DHM),we partitioned the ecosystem carbon pool and carbon exchange into different components,determined the allocation and analyzed relationships within those ***, the total carbon stock of CBM was slightly higher than that of DHM due to a higher carbon stock in the arbor layer at *** was interesting that the proportions of carbon stock in vegetation,soil and litter were similar for the two mature *** ratio of vegetation carbon pool to soil carbon stock was 1.5 at CBM and 1.3 at ***, more carbon was allocated to the trunk and root from the vegetation carbon pool at CBM,while more carbon was allocated to foliage and branches at ***,77% of soil carbon storage was limited to the surface soil layer (0-20cm),while there was still plentiful carbon stored in the deeper soil layers at *** root/shoot ratios were 0.30 and 0.25 for CBM and DHM,*** rates of net ecosystem productivity (NPP)to gross ecosystem productivity (GPP)were 0.76 and 0.58,and the ratios of ecosystem respiration (Re)to GPP were 0.98and 0.87for CBM and DHM,*** net ecosystem carbon exchange/productivity (NEP)was 0.24t C ha^-1 yr^-1 for CBM and 3.38t C ha^-1 yr^-1 for *** to the common seasonal and inter-annual variations of ecosystem carbon exchange resulting from the influence of environmental factors,it was necessary to use the long record dataset to evaluate the ecosystem sink capacity.

关键词： carbon allocation ecosystem carbon stock ecosystem carbon exchange ecosystem productivity mature forest

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Responses of leaf stomatal traits and gas exchange process of cherry tomato to NaCl salinity stress

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Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering 2018年第5期34卷 107-113页

作者： Zhang, Hao Guo, Lili Ye, Jia Zhang, Lei Wang, Qingtao Li, Fei Zhang, Xixi Cao, Xu Xu, Ming Hao, Lihua Zheng, Yunpu College of Life Science and Engineering Handan College Handan056005 China School of Water Conservancy and Hydropower Hebei University of Engineering Handan056038 China School of Landscape and Ecological Engineering Hebei University of Engineering Handan056038 China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographical Sciences and Natural Resources Chinese Academy of Sciences Beijing100101 China Wild Plant Resources Research Centre in Universities in Taihang Mountain of Southern Hebei Province Handan056005 China School of Environment and Resources University of Chinese Academy of Sciences Beijing100039 China

Salinity stress due to the increased use of non-potable water resources for irrigation imposes major limitations on plant growth in salt-affected soils, and meanwhile excessive salinity in the soil may cause osmotic and ionic stresses leading to various physiological and morphological damages to plants. In order to examine the responses of stomatal traits and gas exchange of cherry tomato to salinity stress, we grew cherry tomato seedlings in growth chambers for 21 days with different NaCl concentrations of nutrition medium including 0 (CK), 0.05, 0.10, 0.15, 0.20, and 0.25 mol/L. The parameters related to stomata of leaf were measured. The photosynthesis characteristics were analyzed. The results showed that NaCl stress significantly increased the stomatal density of cherry tomato leaves (Pn) of cherry tomato seedling was gradually decreased with the increase of NaCl concentrations, and the Pn under severe NaCl stress (0.25 mol/L) was significantly different with that of the other NaCl concentrations (Pn of cherry tomato seedling were marginally decreased by 47%, 71%, 77%, 78% and 89% (Pr), stomatal conductance (Gs), and intercellular CO2 concentration (Ci) were also substantially decreased with the increase of NaCl concentrations, and significantly lower than the CK (P © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

关键词： Efficiency

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Impact of land use conversion on soil organic carbon stocks in an agro-pastoral ecotone of Inner Mongolia

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Journal of Geographical Sciences 2017年第8期27卷 999-1010页

作者： ZHAO Wei HU Zhongmin LI Shenggong GUO Qun YANG Hao ZHANG Tonghui Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Naiman Desertification Research Station Northwest Institute of Eco-Environment and Resources CAS Lanzhou 730000 China

Soil organic carbon （SOC） stocks in terrestrial ecosystems vary considerably with land use types. Grassland, forest, and cropland coexist in the agro-pastoral ecotone of Inner Mongolia, China. Using SOC data compiled from literature and field investigations, this study compared SOC stocks and their vertical distributions among three types of ecosystems. The results indicate that grassland had the Largest SOC stock, which was 1.5- and 1.8-folds more than stocks in forest and cropland, respectively. Relative to the stock in 0-100 cm depth, grassland held more than 40% of its SOC stock in the upper 20 cm soil layer; forest and cropland both held over 30% of their respective SOC stocks in the upper 20 cm soil layer. SOC stocks in grazed grasslands were remarkably promoted after -〉20 years of grazing ex- clusion. Conservational cultivation substantially increased the SOC stocks in cropland, espe- cially in the 0-40 cm depth. Stand ages, tree species, and forest types did not have obvious impacts on forest SOC stocks in the study area likely due to the younger stand ages. Our study implies that soil carbon loss should be taken into account during the implementation of ecological projects, such as reclamation and afforestation, in the arid and semi-arid regions of China.

关键词： soil organic carbon soil carbon profile land use change grazing tillage forest age

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Coupling Conservation and Livelihoods for Sustainable Management of Protected Areas in East Africa

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Journal of Resources and Ecology 2018年第3期9卷 266-272页

作者： FU Chao BAI Yunli ZHANG Linxiu WANG Shuai YAN Xue International Ecosystem Management Partnership United Nations Environment Programme Beijing 100101 China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Center for Chinese Agricultural Policy Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical Garden Chinese Academy of Sciences Wuhan 430074 China

Strengthening research efforts to understand the combined impacts of conservation and livelihoods in protected areas（PAs） will increase the collective contribution that PAs can make towards meeting global goals for sustainable development in the next decade. As an example of such efforts, in 2014 the Chinese Academy of Sciences（CAS）, the Kenya Wildlife Service（KWS） and the United Nations Environment Programme（UN Environment） jointly initiated the ＂Sustainable Management of Protected Areas in East Africa＂ project. This paper provides a brief overview of the project＇s research background, goals and research tasks. The study is based on a look at the PA management system in East Africa and a review of the literature on the impact of PAs in the region. Results show that East African nations have expanded the coverage of PAs and established a complex set of PA management systems over the past century. The mandate for PAs in East African nations has changed recently from protecting biodiversity to alleviating poverty and supporting livelihoods. However, a combination of human activities and ecological processes inside and outside of PAs may not only impact biodiversity and ecosystem function over the long term, but also pose a threat to the capacity of PAs to maintain livelihoods and alleviate poverty in the local communities around them. The state of existing research in the field suggests there is an enormous need for additional research, the purpose of which is to help PA managers and policy-makers in East Africa understand how to achieve win-win outcomes for both ecosystems and human well-being. Against this background, the CAS-KWS-UN Environment joint research project aims to understand the dynamic interactions between ecosystems and human well-being around PAs in East Africa and identify good practices for PA management to reconcile conservation targets with the livelihood demands of local communities. It is intended that this research be shared with interested part

关键词： protected areas conservation livelihoods coupling East Africa

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