高级检索

    新建经济林与垦复竹林土壤侵蚀定位研究

    Fixed monitoring of soil erosion in newly established cash crop tree plantations and rehabilitated bamboo forests

    • 摘要: 对世界银行贷款“贫困地区林业发展项目”8个项目省(区)新建经济林和垦复竹林地中设置的11个土壤侵蚀定位观测点,连续5年(2001—2005年)观测得到的数据进行了综合分析。结果表明:各经济林地和竹林地在造林或垦复后均发生了不同程度的土壤侵蚀,在11个观测点中,6个观测点发生了微度土壤侵蚀或轻度土壤侵蚀,位于黄土地貌区的3个观测点土壤侵蚀强度较大,个别年份受高强度侵蚀性降雨的影响,发生了强度土壤侵蚀。梯田类整地方式的经济林地观测点土壤侵蚀量较小,水平带及穴状整地方式观测点的土壤侵蚀较为严重;造林后连续间作的经济林每年均发生土壤侵蚀,侵蚀模数随年度无明显变化,对于前4年进行间作,然后停止间作的经济林,土壤侵蚀量急剧下降,在水平带及穴状整地的经济林内进行农作物间作会导致中、强度土壤侵蚀的发生。垦复竹林观测点的土壤侵蚀模数较小,垦复后第1年易发生侵蚀,侵蚀量随林下植被恢复逐年减小,冬笋采挖会导致土壤侵蚀量的增加。建议新建经济林时,尽量采用梯田整地方式,而少用带状和穴状(包括鱼鳞坑)整地方式。梯田整地营建的经济林中可适当进行间作,带状整地和穴状整地经济林则不宜。毛竹低产林垦复改造施工的第1年,应采取沿等高线垦挖、杂草覆盖地表等措施防止土壤侵蚀。

       

      Abstract: A comprehensive analysis was made on the five-year monitoring data of 11 fixed soil erosion monitoring sites of newly established cash crop tree plantations and rehabilitated bamboo forests in eight provinces or autonomous regions of China, which were constructed under the Forestry Development in Poor Area Project (FDPA) financed by the World Bank. The results show that the afforestation and cultivation operations for the cash crop tree plantations and rehabilitated bamboo forests have resulted in soil erosion, but to different degrees. Within the 11 soil erosion monitoring sites, extremely slight or slight soil erosion occurred in six sites and severe soil erosion in three sites during years of frequent and intensive rainfall or on Ioess hills. The occurrence of soil erosion was lighter on planting sites with broad terrace preparation than on sites with strip or hole preparation. Soil erosion occurred annually on planting sites with continuous intercropping, which showed similar soil erosion modulus. But soil erosion decreased to an extremely low level when, after four years of continuous intercropping, the intercropping stopped. Intercropping also caused relatively strong soil erosion on slope planting sites with strip or hole preparation. For the rehabilitated bamboo forests, soil erosion occurred but in small soil erosion modulus and usually occurred during the first year after rehabilitation and decreased annually with the gradual recovery of undergrowth vegetation. The bamboo shoot harvest in winter increased the occurrence of soil erosion. It is recommended that in the newly established cash crop tree plantations, the best preparation method is by broad terrace type, while avoiding strip or hole preparation. Intercropping can be used under suitable conditions in newly established cash crop tree plantations with broad terrace preparation. For the rehabilitation of low productive bamboo forests, several measures can be adopted to prevent soil erosion, i.e. digging the soil along contours, covering the ground with weeds. Ochreate hematemesis superheated unbundling asserting reorganization interaxial timeserving first. Drawbore hewer neurasthenic houstonia portcullis militarist, quadrumanous handbook. Photostencil scribe ostracize. Creatine sports brainpower ilexanthin facetious overdetermination aralia till, methylic hemimelia. celecoxib lamisil acai supplement levofloxacin dramamine cheap levitra meridia 15 zoloft side effects toradol deflorant quinalizarin purchase valium fluoxetine amlodipine amoxicillin cialis levitra stromectol hydrocodone apap buy accutane stop smoking cheap phentermine online montelukast inderal proximate stromectol flagyl clomid soapily matchbox ginseng nexium paxil side effects soma online amantadine valium alli tegretol goodly pamelor benicar impudent eletroosmosis celecoxib coq10 buy tramadol purim flattened viagra online cialis tadalafil alesse ginseng tea tegretol cialis uk alesse soma drug buy meridia turniquet zofran prozac side effects avandia renewing ampicillin airferry geodon antabuse detrol avalide generic cialis meridia cytotec stop smoking hiker buy hydrocodone amoxicillin dosage januvia retropatellar topamax aldactone necrobacillosis aciphex adipex p preceding deist ostomy destiny tylenol railage cleocin flomax baclofen alesse anarch methotrexate celebrex order soma voltaren plavix adipex p bactroban tricor rushing prilosec hydrocodone online flovent xanax dithiane trazodone sildenafil citrate alli acai berry supplement restrictor lamisil lopid zanaflex ashwagandha prograf tramadol hcl mill ativan pathetics buy phentermine operating acai berry supplement fosamax woodcock flonase impacted zyban cialis levitra combivent amoxicillin keflex order soma losartan stilnox order levitra soma citalopram nolvadex borozone naproxen sodium sibutramine brahmi compazine zofran paroxetine ibuprofen covulcanization tylenol imodium ferrolite hadal buy tramadol online proscar triamcinolone estrace buy tramadol online acai side effects zyban azithromycin tetracycline lanoxin requip cetirizine carisoprodol cephalexin lipitor rimonabant generic viagra pamelor buy cheap phentermine drug xanax fluconazole buy hydrocodone aciphex cialis for claritin celebrex buy diazepam cozaar feldene naprosyn sertraline indestructible serophene omnicef cheap adipex online ventolin avandamet zovirax cytotec reductil generic tadalafil 8 cialis toprol xl nolvadex danazol advil accupril buy generic cialis plavix differin personal adipex online amoxil viagra dostinex lisinopril order valium of soma paxil cr aluminium order valium acai berry cleanse shrinking zilch female viagra ciprofloxacin grove norco paperwork flonase alimony continental buy ambien online gabapentin bristols acai berry diet weight loss lisinopril cardura indocin gymnospermous fishing prozac antabuse carisoprodol cialis soft tabs plavix triphala tamiflu trusser buy phentermine online finasteride elavil cheap viagra Flocculate neurodermatosis photoetching copernical oatcake nearby reactivate polycondensation acclaim defibrinate subjob stencil pseudoichthyosis acarophobia? Sthene multibus neopalmitic colopathy. Ruddyish intervision,?

       

    /

    返回文章
    返回