1674-5906
2012 Issue 4
Tidal action and tread affecting nitrous oxide fluxes in intertidal Cyperus malaccensis var.brevifolius marsh
ZHANG Yongxun;ZENG Congsheng;TONG chuan;WANG Weiqi;HUANG Jiafang;HE Qinghua 1.School of Geographical Science;Fujian Normal University;Fuzhou 350007;China;2.Research Center of Wetlands in Subtropical Region;Fujian Normal University;Fuzhou 350007;China;3.Key Laboratory of Humid Sub-tropical Eco-geographical Process of Ministry of Education;Fujian Normal University;Fuzhou 350007;China
ZHANG Yongxun;ZENG Congsheng;TONG chuan;WANG Weiqi;HUANG Jiafang;HE Qinghua 1.School of Geographical Science;Fujian Normal University;Fuzhou 350007;China;2.Research Center of Wetlands in Subtropical Region;Fujian Normal University;Fuzhou 350007;China;3.Key Laboratory of Humid Sub-tropical Eco-geographical Process of Ministry of Education;Fujian Normal University;Fuzhou 350007;China
..............page:641-646
Carbon content rate in dominant species of four forest types in Shangri-la,northwest Yunnan province
WANG Jinliang1;WANG Xiaohua1;YUE Cairong2;CHENG Feng1;XUE Tianshu2;CHENG Pengfei1;WANG Xuemei1;GAO Yan1 1.College of Tourism and Geographical Science;Yunnan Normal University;Kunming 650092;China;2.College of Resources;Southwest Forestry University;Kunming 650092;China
WANG Jinliang1;WANG Xiaohua1;YUE Cairong2;CHENG Feng1;XUE Tianshu2;CHENG Pengfei1;WANG Xuemei1;GAO Yan1 1.College of Tourism and Geographical Science;Yunnan Normal University;Kunming 650092;China;2.College of Resources;Southwest Forestry University;Kunming 650092;China
..............page:613-619
Analysis on soil characters of the growing environment and nutrition characteristic of Aquilaria sinensis
WANG Ran2;HE Qian1;DING Xiaogang3;LI Jiyue1;ZHANG Fangqiu3;PAN Wen3 1.College of Forestry;South China Agricultural University;Guangzhou 510642;2.Henan forest aviation fire station;Zhengzhou;471003;3.Guangdong Forest Research Institute;Guangzhou 510520;
WANG Ran2;HE Qian1;DING Xiaogang3;LI Jiyue1;ZHANG Fangqiu3;PAN Wen3 1.College of Forestry;South China Agricultural University;Guangzhou 510642;2.Henan forest aviation fire station;Zhengzhou;471003;3.Guangdong Forest Research Institute;Guangzhou 510520;
..............page:666-672
Character of heavy metals of main foodstuff crop and soil in three gorges reservoir
LI Qilin1;HUANG Yun2;WANG Ping1;LIU Fengyi1 1.College of Chemistry and Chemical Engineering;Yun’nan Normal University;Kunming 650500;China;2.Chongqing Agricultural Food Quality and Safety Center;Chongqing 400020;China
LI Qilin1;HUANG Yun2;WANG Ping1;LIU Fengyi1 1.College of Chemistry and Chemical Engineering;Yun’nan Normal University;Kunming 650500;China;2.Chongqing Agricultural Food Quality and Safety Center;Chongqing 400020;China
..............page:764-769
Influencing factor analysis of Escherichia coli inhibition by Ag(Ⅰ)
XU Fangfang;WANG Wenzhao;HUANG Manhong;CHEN Liang College of environmental Science and Engineering;Donghua Unviersity;Shanghai 201620;China
XU Fangfang;WANG Wenzhao;HUANG Manhong;CHEN Liang College of environmental Science and Engineering;Donghua Unviersity;Shanghai 201620;China
..............page:750-753
Review of theory research on ecological compensation
TAO Jiange Zhongyuan University of Technology;Zhengzhou 450007;China
TAO Jiange Zhongyuan University of Technology;Zhengzhou 450007;China
..............page:786-792
..............page:793
Particle size distribution of heavy metals in surface dusts from different functional zones of Luoyang city
LIU Dehong;WANG Fayuan;KOU Taiji Agricultural College;Henan University of Science and Technology;Luoyang 471003;China
LIU Dehong;WANG Fayuan;KOU Taiji Agricultural College;Henan University of Science and Technology;Luoyang 471003;China
..............page:700-705
Decontamination ability of sulfur dioxide and nitrogen dioxide for 38 young landscaping plants in Guangzhou city
PAN Wen1;ZHANG Weiqiang1;ZHANG Fangqiu1;LIU Jiping2;DUAN Jinping;CHEN Jie3 1.Guangdong Academy of Forestry;Guangzhou 510520;China;2 Enterprise Construction Bureau of the Guangzhou Nansha Economic and Technological Development Zone;Guangzhou 514000;China;3 Guangzhou Nansha District Bureau of Agriculture and Forestry;Guangzhou 514000;China
PAN Wen1;ZHANG Weiqiang1;ZHANG Fangqiu1;LIU Jiping2;DUAN Jinping;CHEN Jie3 1.Guangdong Academy of Forestry;Guangzhou 510520;China;2 Enterprise Construction Bureau of the Guangzhou Nansha Economic and Technological Development Zone;Guangzhou 514000;China;3 Guangzhou Nansha District Bureau of Agriculture and Forestry;Guangzhou 514000;China
..............page:606-612
Profile distribution of soil available phosphorus and available potassium concentrations and crop grain yields in long-term fertilization experiment
HU Cheng1;SONG Jiayong2;LI Jing2;LIU Chunqing3;TAO Xiao’e3;CHEN Yunfeng1;QIAO Yan1;LI Shuanglai1;LIU Donghai1 1.Institute of Plant Protection and Soil Sciences;Hubei Academy of Agricultural Sciences;Wuhan 430064;China;2.Soil and Fertilizer Station of Hubei Province;Wuhan 430070;China;3.Agriculture Bureau of Xinan District in Xiaogan;Xiaogan 432000;China
HU Cheng1;SONG Jiayong2;LI Jing2;LIU Chunqing3;TAO Xiao’e3;CHEN Yunfeng1;QIAO Yan1;LI Shuanglai1;LIU Donghai1 1.Institute of Plant Protection and Soil Sciences;Hubei Academy of Agricultural Sciences;Wuhan 430064;China;2.Soil and Fertilizer Station of Hubei Province;Wuhan 430070;China;3.Agriculture Bureau of Xinan District in Xiaogan;Xiaogan 432000;China
..............page:673-676
Comparison between water-submerging-cultivation and dry farming in reducing Cd concentration in waterspinach
WANG Yanhong;LI Mengjun;TANG Mingdeng;AI Shaoying;YU Danni;LUO Yingjian Institute of Soil and Fertilizer;Guangdong Academy of Agricultural Sciences;Guangdong Key Laboratory of Nutrient Cycling and Farmland Conservation;Guangzhou 510640;China
WANG Yanhong;LI Mengjun;TANG Mingdeng;AI Shaoying;YU Danni;LUO Yingjian Institute of Soil and Fertilizer;Guangdong Academy of Agricultural Sciences;Guangdong Key Laboratory of Nutrient Cycling and Farmland Conservation;Guangzhou 510640;China
..............page:770-774
Analysis of multi-year measurements of dissolved total nitrogen and phosphorus in the Mirs Bay
ZHOU Yipin1;LI Xulu2;ZHANG Junxiao2;XIA Huayong2 1.South China Sea lnstitute of Oceanology;Chinese Academy of Sciences;Guangzhou 510301;China;2.South China Sea Marine Engineering Surveying Center;SOA;Guangzhou 510300;China
ZHOU Yipin1;LI Xulu2;ZHANG Junxiao2;XIA Huayong2 1.South China Sea lnstitute of Oceanology;Chinese Academy of Sciences;Guangzhou 510301;China;2.South China Sea Marine Engineering Surveying Center;SOA;Guangzhou 510300;China
..............page:706-710
Correlative research on rhizosphere soil enzyme activities and available trace elements under reduced solar irradiance
WU Fangfang;ZHENG Youfei;WU Rongjun;LI Ping Jiangsu Key Laboratory of Atmospheric environmental monitoring and Pollution control high-tech research;School of Environmental Science and Engineering;Nanjing University of Information Science & Technology;Nanjing 210044;China
WU Fangfang;ZHENG Youfei;WU Rongjun;LI Ping Jiangsu Key Laboratory of Atmospheric environmental monitoring and Pollution control high-tech research;School of Environmental Science and Engineering;Nanjing University of Information Science & Technology;Nanjing 210044;China
..............page:595-600
Effect of freezing-thawing on the carbon and nitrogen mineralization in Changbai Mountain
JIA Guojing1;2;ZHOU Yongbin1;DAI Limin2;ZHOU Wangming2 1.The Academy of Forestry of Shenyang Agricultural University;Shenyang 110866;China;2.Institute of Applied Ecology;CAS;Shenyang 130012;China
JIA Guojing1;2;ZHOU Yongbin1;DAI Limin2;ZHOU Wangming2 1.The Academy of Forestry of Shenyang Agricultural University;Shenyang 110866;China;2.Institute of Applied Ecology;CAS;Shenyang 130012;China
..............page:624-628
Soil moisture content and nitrogen impacts on soil organic carbon of saline-alkali paddy field under the effect of freeze-thaw
TANG Jie;LOU Yun;LI Na;LI Zhaoyang;ZHANG Hao;LIANG Shuang College of Environment and Resource;Jilin University;Changchun 130012;China
TANG Jie;LOU Yun;LI Na;LI Zhaoyang;ZHANG Hao;LIANG Shuang College of Environment and Resource;Jilin University;Changchun 130012;China
..............page:620-623
Research on condition of China’s industrial smoke emission
LIU Ruijie;ZHANG Zhihui Department of Construction Management;Tsinghua University;Beijing 100084;China
LIU Ruijie;ZHANG Zhihui Department of Construction Management;Tsinghua University;Beijing 100084;China
..............page:694-699
Hydrolysis of pyridaphenthione and its degradation in soils
ZHAO Feng1;LUO Jing2;WANG Minghua1 1.College of Plant Protection;Nanjing Agricultural University;Nanjing 210095;China;2.Institute of Special Wild Economic Animals and Plants;Chinese Academy of Agricultural Sciences;Jilin 132109;China
ZHAO Feng1;LUO Jing2;WANG Minghua1 1.College of Plant Protection;Nanjing Agricultural University;Nanjing 210095;China;2.Institute of Special Wild Economic Animals and Plants;Chinese Academy of Agricultural Sciences;Jilin 132109;China
..............page:780-785
Analysis on spatial distribution characteristic of export load of water pollutants in industrial city of Pearl River delta
XIE Yiwen1;GAO Weiping2;NING Yurong3;WEI Zhongyuan3;XIE Guangliang4;HE Fengxia1 1.College of Chemical and Environmental Engineering;Dongguan University of Technology;Dongguan 523808;China;2.Bureau of Pearl River Basin Water Resources Protection;Guangzhou 510611;China;3.Sichuan Water Resources and Hydroelectric Investigation & Design Institute of the Ministry of Water Resources;Chengdu 610072;China;4.Water Affairs Bureau of Dongguan City;Dongguan 523888;China
XIE Yiwen1;GAO Weiping2;NING Yurong3;WEI Zhongyuan3;XIE Guangliang4;HE Fengxia1 1.College of Chemical and Environmental Engineering;Dongguan University of Technology;Dongguan 523808;China;2.Bureau of Pearl River Basin Water Resources Protection;Guangzhou 510611;China;3.Sichuan Water Resources and Hydroelectric Investigation & Design Institute of the Ministry of Water Resources;Chengdu 610072;China;4.Water Affairs Bureau of Dongguan City;Dongguan 523888;China
..............page:711-714
Enhanced Fe~0 PRB technology for the remediation of PCBs contaminated groundwater
LIU Yuanyuan;GAO Song;QIU Mingying;LV Chunxin;ZHANG Lanying Key Laboratory of Groundwater Resources and Environment;Ministry of Education;Jilin University;Changchun Jilin 130026;China
LIU Yuanyuan;GAO Song;QIU Mingying;LV Chunxin;ZHANG Lanying Key Laboratory of Groundwater Resources and Environment;Ministry of Education;Jilin University;Changchun Jilin 130026;China
..............page:733-736
Response of methanotrophic community structure and oxidation potential to cadmium stress in a Chinese paddy soil
ZHENG Yong1;ZHENG Yuanming2;HE Jizheng2 1.State Key Laboratory of Mycology;Institute of Microbiology;Chinese Academy of Sciences;Beijing 100101;China;2.State Key Laboratory of Urban and Regional Ecology;Research Center for Eco-Environmental Sciences;Chinese Academy of Sciences;Beijing 100085;China
ZHENG Yong1;ZHENG Yuanming2;HE Jizheng2 1.State Key Laboratory of Mycology;Institute of Microbiology;Chinese Academy of Sciences;Beijing 100101;China;2.State Key Laboratory of Urban and Regional Ecology;Research Center for Eco-Environmental Sciences;Chinese Academy of Sciences;Beijing 100085;China
..............page:737-743
Isolation and identification of a strain degradating poly (butylene succinate)
ZHANG Min1;SHEN Yinghui1;LI Chengtao1;ZHANG Huan1;ZHANG Rui1;HU Xiaoping2 1.Key Laboratory of Auxiliary Chemistry & technology for Chemical Industry;Ministry of Education;Shaanxi University of Science & Technology;Xi’an;Shaanxi 710021;China;2.State Key Laboratory of Crop Stress Biology for Arid Areas;Northwest Agriculture & Forestry University;Yangling;Shaanxi 712100;China
ZHANG Min1;SHEN Yinghui1;LI Chengtao1;ZHANG Huan1;ZHANG Rui1;HU Xiaoping2 1.Key Laboratory of Auxiliary Chemistry & technology for Chemical Industry;Ministry of Education;Shaanxi University of Science & Technology;Xi’an;Shaanxi 710021;China;2.State Key Laboratory of Crop Stress Biology for Arid Areas;Northwest Agriculture & Forestry University;Yangling;Shaanxi 712100;China
..............page:775-779
..............page:793
The research of non-standard test method in soil heavy metal by X-Ray fluorescence pectrometry
TAN Heping;GAO Yang;LV Hao;ZHANG Yulan;SUN Yujie National Institute of Measurement and Testing Technology;Chengdu 610021;China
TAN Heping;GAO Yang;LV Hao;ZHANG Yulan;SUN Yujie National Institute of Measurement and Testing Technology;Chengdu 610021;China
..............page:760-763
An analysis of carbon inequality between different income levels in China 1999-2009
WANG Qin1;QU Jiansheng2;3 1.Guangzhou Research Institute of Environmental Protection;Guangzhou 510620;China;2.Scientific Information Center for Resources and Environment;Lanzhou Branch of the National Science Library;Chinese Academy of Sciences;Lanzhou 730000;China;3.Key Laboratory of Western China’s Environmental Systems;Lanzhou University;Lanzhou 730000;China
WANG Qin1;QU Jiansheng2;3 1.Guangzhou Research Institute of Environmental Protection;Guangzhou 510620;China;2.Scientific Information Center for Resources and Environment;Lanzhou Branch of the National Science Library;Chinese Academy of Sciences;Lanzhou 730000;China;3.Key Laboratory of Western China’s Environmental Systems;Lanzhou University;Lanzhou 730000;China
..............page:635-640
..............page:794
The comparative effect between 1-Naphthol and 17β- estradiol on estrogen effect in male Tilapia (GIFT Oreochromis niloticus)
CHEN Jiazhang 1;2 *;WANG Zerong 2;QU Jianhong 1;QIU Liping 1;HU Gengdong 1 1.Scientific Observing and Experimental Station of Fishery Resources and Environment in the Lower Reaches of the Changjiang River//Ministry of Agriculture;Freshwater Fisheries Research Center;Chinese Academy of Fishery Sciences;Wuxi 214081;China;2.Wuxi Fishery College;Nanjing Agricultural University;Wuxi 214081
CHEN Jiazhang 1;2 *;WANG Zerong 2;QU Jianhong 1;QIU Liping 1;HU Gengdong 1 1.Scientific Observing and Experimental Station of Fishery Resources and Environment in the Lower Reaches of the Changjiang River//Ministry of Agriculture;Freshwater Fisheries Research Center;Chinese Academy of Fishery Sciences;Wuxi 214081;China;2.Wuxi Fishery College;Nanjing Agricultural University;Wuxi 214081
..............page:754-759
A combined biological-chemical approach supported by granulated iron and methanol for nitrate removal from oxygen rich groundwater
HUANG Guoxin1;FALLOWFIELD Howard2;GUAN Huade2;LIU Fei3 1.China Meat Research Center;Beijing 100068;China;2.School of the Environment;Flinders University;Sturt Road;Bedford Park;SA 5001;Australia;3.Beijing Key Laboratory of Water Resources & Environmental Engineering;China University of Geosciences;Beijing 100083;China
HUANG Guoxin1;FALLOWFIELD Howard2;GUAN Huade2;LIU Fei3 1.China Meat Research Center;Beijing 100068;China;2.School of the Environment;Flinders University;Sturt Road;Bedford Park;SA 5001;Australia;3.Beijing Key Laboratory of Water Resources & Environmental Engineering;China University of Geosciences;Beijing 100083;China
..............page:726-732
Effects of corn straws plus nitrogen fertilizer on the soil nutrients and enzymatic activities in the arid area of Eastern Liaoning province
GAO Jinhu1;SUN Zhanxiang2;FENG Liangshan1;2;WU Changjuan1 1.College of Land and Environment;Shenyang agriculture university;Shenyang 110866;China;2.Liaoning academy of agricultural sciences;Shenyang 110161;China
GAO Jinhu1;SUN Zhanxiang2;FENG Liangshan1;2;WU Changjuan1 1.College of Land and Environment;Shenyang agriculture university;Shenyang 110866;China;2.Liaoning academy of agricultural sciences;Shenyang 110161;China
..............page:677-681
The release law of phosphorus in the anaerobic sludge and the research on the recovery of phosphorus by struvite precipitation
SUN Lianpeng1;2;SHEN Ruifang1;LI Shuduan3;YE Siqin1;TANG Zhe1;WU Shijia1 1.School of Environmental Science and Engineering;Sun Yat-sen Univerisity;Guangzhou 510275;China;2.Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology;Guangzhou 510275;China;3.Guangzhou Center for Disease Control and Prevention;Guangzhou 510090;China
SUN Lianpeng1;2;SHEN Ruifang1;LI Shuduan3;YE Siqin1;TANG Zhe1;WU Shijia1 1.School of Environmental Science and Engineering;Sun Yat-sen Univerisity;Guangzhou 510275;China;2.Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology;Guangzhou 510275;China;3.Guangzhou Center for Disease Control and Prevention;Guangzhou 510090;China
..............page:715-719
Diversity and resistance of rhizobia from legumes in Lanping lead and zinc mine tailings
WANG Jinhua;LIU Shaoxiong;ZHU Lili;LI Biao;XIONG Zhi Key Laboratory for Forest Resources Conservation and Use in the Sorthwest Mountains of China Ministry of Education;Southwest Forestry University;Yunnan;Kunming 650224;China
WANG Jinhua;LIU Shaoxiong;ZHU Lili;LI Biao;XIONG Zhi Key Laboratory for Forest Resources Conservation and Use in the Sorthwest Mountains of China Ministry of Education;Southwest Forestry University;Yunnan;Kunming 650224;China
..............page:744-749
Characteristics of soil erosion on sloping farmlands in a purple hilly region of the Sichuan Basin
NIE Xiaojun1;SU Yanyan2 1.School of Surveying and Land Information Engineering;Henan Polytechnic University;Jiaozuo 454000;China 2.Politics and Management Technology College;Henan Normal University;Xinxiang 453007;China
NIE Xiaojun1;SU Yanyan2 1.School of Surveying and Land Information Engineering;Henan Polytechnic University;Jiaozuo 454000;China 2.Politics and Management Technology College;Henan Normal University;Xinxiang 453007;China
..............page:682-686
Modeling the impacts of temperature changes on hydrological effects of forests in the mountain region of southwestern China at basin scale
DENG Huiping School of Environment and Planning;Liaocheng University;Liaocheng 252059;China
DENG Huiping School of Environment and Planning;Liaocheng University;Liaocheng 252059;China
..............page:601-605
Antimicrobial activity of metabolites and isolation of endophytic fungi in Betula spp.
ZANG Wei 1;2;HE Xu 3;SUN Jianqiu 1;3;SONG Ruiqing 2;YU Wenxi 2;LI Tie 3;WANG Hong 3;ZHENG Yebo 1;LI Hui 1 1.College of Life Sciences;Shaoxing University;Shaoxing 312000;China;2.Heilongjiang Forestry Academy of Science;Harbin 150081;China;3.College of Life Sciences;Qiqihar University;Qiqihar 161006;China
ZANG Wei 1;2;HE Xu 3;SUN Jianqiu 1;3;SONG Ruiqing 2;YU Wenxi 2;LI Tie 3;WANG Hong 3;ZHENG Yebo 1;LI Hui 1 1.College of Life Sciences;Shaoxing University;Shaoxing 312000;China;2.Heilongjiang Forestry Academy of Science;Harbin 150081;China;3.College of Life Sciences;Qiqihar University;Qiqihar 161006;China
..............page:661-665
Experimental simulation study of microbial degradation of BTEX in the river filtration system
MA Yan;LI Zhiping;LIANG Ke;LIU Mingzhu School of Resources and Environment;North China Institute of Water Conservancy and Hydroelectric Power;Zhengzhou 450011;China
MA Yan;LI Zhiping;LIANG Ke;LIU Mingzhu School of Resources and Environment;North China Institute of Water Conservancy and Hydroelectric Power;Zhengzhou 450011;China
..............page:720-725
Analyses on pathotypic diversity of Xanthomonas oryzae pv. oryzae along altitude gradient and driving forces in southwestern China
CHEN Xiaolong1;GAO Lingling1;YU Lei2;SUN Yuexian1;MA Jie3;HUANG Qiong1 1.The Ministry of Education Key Laboratory for Agriculture Biodiversity and Plant Disease Management;Key Laboratory of Plant Pathology;Yunnan Agricultural University;Kunming 650201;China;2.College of agronomy;Kunming University;Kunming 650214;China;3.Anyang Normal University;Anyang 455000;China
CHEN Xiaolong1;GAO Lingling1;YU Lei2;SUN Yuexian1;MA Jie3;HUANG Qiong1 1.The Ministry of Education Key Laboratory for Agriculture Biodiversity and Plant Disease Management;Key Laboratory of Plant Pathology;Yunnan Agricultural University;Kunming 650201;China;2.College of agronomy;Kunming University;Kunming 650214;China;3.Anyang Normal University;Anyang 455000;China
..............page:654-660
Response of litter decomposition to changes of litter input in a pine forest of Dinghushan
MA Chuan;DONG Shaofeng;MO Jiangming Dinghushan Forest Ecosystem Research Station;South China Botanical Garden;Chinese Academy of Sciences;Zhaoqing;Guangdong 510650;China
MA Chuan;DONG Shaofeng;MO Jiangming Dinghushan Forest Ecosystem Research Station;South China Botanical Garden;Chinese Academy of Sciences;Zhaoqing;Guangdong 510650;China
..............page:647-653
CO2-release rate of soil respiration and litter decomposition in summer of four plant communities in desert steppe
CHEN Lin;LI Xuebin;WANG Lei;LIU Bingru;WANG Xinyun Key Laboratory of Restoration and Reconstruction of Degraded Ecosystem in North-western China;Ministry of Education;State Key Laboratory Breeding Base of Land Degradation and Ecological Restoration of North-western China;Ningxia University;Yinchuan 750021;China
CHEN Lin;LI Xuebin;WANG Lei;LIU Bingru;WANG Xinyun Key Laboratory of Restoration and Reconstruction of Degraded Ecosystem in North-western China;Ministry of Education;State Key Laboratory Breeding Base of Land Degradation and Ecological Restoration of North-western China;Ningxia University;Yinchuan 750021;China
..............page:629-634
..............page:793
Spatial pattern differences between urban and rural construction land in multi-scales
LEI Yakai1;HE Dan2;TIAN Guohang3;ZHANG Junhong1 1.Chinese Academy of Forestry;Beijing 100091;China;2.Beijing Forestry University;Beijing 100091;China;3.Henan Agricultural University;Zhengzhou 450002;China
LEI Yakai1;HE Dan2;TIAN Guohang3;ZHANG Junhong1 1.Chinese Academy of Forestry;Beijing 100091;China;2.Beijing Forestry University;Beijing 100091;China;3.Henan Agricultural University;Zhengzhou 450002;China
..............page:687-693