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The effects of temperatures and salinities on germination of two halophytes, Kalidium capsicum and Suaeda physophora in northwestern China, were tested, and their seed size and seed production were compared. It was found that seed of Suaeda physophora germinate under 10℃, even about 0℃, and at a wide temperature range of 10―30℃. It showed about 50% germination in the concentration up to 0.7 mol/L NaCl; optimum germination temperature of Kalidium capsicum was between 20℃ and 30℃. The concentration of less than 0.3 mol/L NaCl inhibited absolutely its germination. Germination recovery was observed when salinities were reduced and total germination percentage exceeded 90%. Seeds of Kalidium capsicum showed no loss of viability while Suaeda physophora an annual loss of viability of 75% at room temperature. Mean weight of seeds of Suaeda physophora was about 8.5 times of Kalidium capsicum, whereas the number of seeds of the latter was more than 20 times of the former. Suaeda physophora was observed to be dependent on periodic precipitation in germination and seedling growth. It suggests the evident trace of the species with zonation pattern. On the other hand, the germination of Kalidium capsicum was affected by unpredictable rain and inundation. This species might be a type without zonation patterns in halophytes. It was concluded that both species are halophytes, but they are established successfully by different adaptation strategies in the early stage of life history.  相似文献   
2.
The impact of Mn in manganese waste rocks and electrolytic manganese residues on the growth of capsicum was studied via pot experiments. The product yield and manganese nutrition were mainly evaluated in this study. The results showed that the ingredients of manganese tailings were beneficial to the increase of chlorophyll contents in the capsicum. The chlorophyll contents were raised by 12.6%–28.7%, 7.18%–12.1% and 9.70%–13.7%, respectively, corresponding to the idiophase of flower bud, the initial florescence and the fruit expansion stage. Moreover, the additive significantly improved capsicum’s economic features, such as its height, stem width, fruit length and weight and the yield of fresh fruit. These parameters were raised by 11.9%–25%, 18.6%–25.6%, 20.7%–35.4%, 10.4%–27.6% and 11.4%–65.7%, respectively. At the meantime, the manganese taken up by stems and leaves of the capsicum also increased by 11.7%–23.4% and 33.9%–62.8%, respectively. The manganese which remained in the soil was less than that in the original soil due to plant absorption and rainfall loss in pot experiments. It is concluded that both manganese residues and the mixture of manganese waste rock and manganese residue could indeed be made full use of as a fertilizer which can provide Mn nutrition.  相似文献   
3.
荒漠草原2种植物群落土壤微生物及土壤酶特征   总被引:7,自引:2,他引:5  
测定和分析了甘肃省金昌市金川区荒漠草原土壤微生物数量、微生物生物量和土壤酶活性。结果表明:同层土壤3大类微生物(真菌、细菌和放线菌)数量、土壤微生物量碳和氮含量及4类土壤酶(蔗糖酶、脲酶、磷酸酶和过氧化氢酶)活性均表现为盐爪爪(Kalidium foliatum)群落大于骆驼刺(Alhagi sparsifolia)群落,而土壤微生物量磷含量相反;同一植物群落,不同层土壤微生物数量(除骆驼刺群落中的真菌亚表层最高外)、土壤微生物量碳、氮、磷含量及土壤酶活性(除骆驼刺群落中脲酶呈现高-低-高-低趋势外)均呈现随土层的加深而降低的趋势;金川区荒漠草原不同植物群落不同空间层次土壤微生物数量、微生物生物量和各种酶之间有不同程度的相关性。  相似文献   
4.
滇黔地区室内燃煤污染所致慢性氟中毒是我国特有的长期困扰我国的主要环境健康问题之一。为了探讨滇黔"燃煤污染型"氟中毒重症区粮食氟和砷含量及污染的主要途径和改灶降氟炉的使用状况及氟中毒防治效果等,从2005年至2008年11月,连续在云南省和贵州省氟中毒较严重的地区——昭通市的镇雄、威信、大关、彝良、昭阳区以及贵州威宁石门坎、毕节、郝章和非病区昭通巧家、鲁甸县等地,调查了当地500余户改灶降氟炉的使用状况、生活习惯及粮食干燥和保存方式、儿童氟斑牙患病率等,系统采集和分析测定了改灶降氟炉使用区和非使用区烘烤前后粮食的氟和砷等含量。结果发现:无论重病区或非病区,未烘烤粮食的新鲜玉米的氟含量均低于4μg/g,一般为1~2μg/g,砷含量低于0.1μg/g,一般在0.01~0.05μg/g之间;而敞炉快速烘烤(10~15天)的玉米氟含量比烘烤前增加4~200倍,一般在10倍以上,含量在10~20μg/g之间;辣椒氟含量比烘烤前增加了30~100倍,最高达1274.39μg/g;烘烤辣椒的含氟量一般高于玉米的氟含量,均高于20μg/g;砷的含量也10~40倍地增加,增加幅度与氟相当。被调查的500余户烘烤粮食的居民中,无论改灶降氟炉使用户或非使用户,只要是需要烘烤粮食的用户,没有一户是单独使用改灶降氟炉烘烤粮食,全部用2~3个以上的敞炉烘烤粮食,其烘烤后的粮食的氟和砷污染程度相当。结论:滇黔"燃煤污染型"氟中毒区重症区大多数新鲜玉米和辣椒的氟和砷的含量低于或稍高于国家标准;无论烘烤粮食的煤及拌煤黏土中氟和砷含量的高低,烘烤后的玉米和辣椒的氟含量全部超标,砷含量增加十倍以上,敞炉快速烘烤粮食是滇黔氟中毒重症区的粮食氟和砷污染的主要路径和主要成因。改灶降氟炉的推广,不能降低滇黔"燃煤污染型"氟中毒区粮食的氟污染、根治燃煤污染型氟中毒症发生的主要原因,是当地潮湿多雨,气候阴冷,而改灶降氟炉的火力太小,无法在短期内快速烘烤干粮食,所以,无论改灶降氟炉使用区或非使用区,全部用敞炉烘烤粮食。因而在阴冷潮湿的滇黔山区,仅仅推广火力较小的改灶降氟炉,无法隔断烘烤粮食时的氟污染源,对防治滇黔"燃煤污染型"氟中毒是远远不够的。  相似文献   
5.
用灰色系统关联度及统计方法对玻璃温室内辣椒生长状况、生物量与室内10种气象要素进行定量分析,得出影响辣椒生产各气象要素的指标。  相似文献   
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