一区白丝二区精选精品,欧美成人一区二区免费,91亚洲国产成人久久,亚洲精品乱码久久久蜜臀,日韩av大片免费在线观看,国产又黑又粗又黄又爽,日韩中文字幕美艳人妻,欧美丰满大屁股在线喷水,日韩欧美国产午夜视频,一级黄片国产精品久久

    <rt id="4xhpc"><small id="4xhpc"></small></rt>
        <li id="4xhpc"></li>
        1. <label id="4xhpc"></label>
          <li id="4xhpc"></li>

          Green sun screen dust screen

          Canopy products > Shading net > Green sun screen dust screen

          Green sun screen dust screen

          Model of sunscreen: 2.5, 3, 3.5, 4, 6, 8, 12

          Model of sunscreen: 2.5, 3, 3.5, 4, 6, 8, 12

          Shade color: black, green

          Sunshade net, also known as sunshade net, is a new type of special protective covering material for agriculture, fishery, animal husbandry, windbreak, soil cover and so on, which has been popularized in recent 10 years. After covering in summer, it plays a role of keeping out light, rain, moisture and temperature. After covering in winter and spring, it can keep warm and increase humidity.

          Generally, the leaf vegetables planted in winter and spring cover the surface of leaf vegetables directly with sunshade net (floating cover) to prevent low temperature damage. Because of its light weight, it is only about 45 grams per square meter, and it will not overwhelm, bend or reduce the commerciality of the grown high leaf vegetables. Because of its air permeability, the leaf surface is still dry after covering, which reduces the occurrence of disease. It also has a certain transparency, after covering, it will not "cover yellow, cover rotten". In 1997, Henan Agricultural University in Longtang vegetable Park, Linying County, protected the winter celery in the shed. The results showed that under the condition of - 6 ℃, there was no ice in the leaves of celery; However, the temperature of the control group, especially the upper and middle leaves, was 1.5 ℃ higher than that of the control group.

                 Sunscreen is mainly used in summer, especially in the south. Some people describe it as: the winter in the north is white (covered with film), and the summer in the south is black (covered with sunscreen). In summer, using sunshade net to cultivate vegetables in South China has become a main technical measure for disaster prevention and protection. The application in the north is only limited to the cultivation of vegetable seedlings in summer. In summer (June August), the main function of covering sunshade is to prevent the exposure of hot sun, the impact of rainstorm, the harm of high temperature, the spread of pests, especially to prevent the migration of pests.

                 After covering in summer, it plays a role in keeping out light, rain, moisture and cooling; after covering in winter and spring, it also has a certain role in heat preservation and humidification.

                 Moistening principle: after the sunshade is covered, because of the cooling and windproof effect, the communication speed between the air in the covered area and the outside world is reduced, the relative humidity of the air is significantly further increased. At noon, the humidity increase value is the largest, generally reaching 13-17%. The humidity is high, the soil evaporation is reduced, and the soil humidity is increased.

                 The sunshade is made of polyethylene (HDPE), high-density polyethylene, PE, Pb, PVC, recycled material, brand-new material, polyethylene propylene and other raw materials. After UV stabilizer and anti-oxidation treatment, it has the characteristics of strong tensile strength, aging resistance, corrosion resistance, radiation resistance and portability. It is mainly used in the protective cultivation of vegetables, Xianggu, flowers, edible fungi, seedlings, medicinal materials, ginseng, Ganoderma lucidum and other crops, as well as the aquaculture and poultry industry, etc., which has obvious effect on improving the yield.



          操到高潮喷水在线观看| 亚洲一区二区久久青草| 裸体一区二区三区av| 午夜无码国产理论在线| 中文字幕日韩精品有码视频| 欧美天天综合色影久久精品| 一区二区三区视频不卡| 熟女少妇大屁股精品一二区| 久草国产成人在线视频网| 少妇人妻无码专区在线视频 | 久久久午夜精品理论片| 精品亚洲一区二区视频| 男男互吃大丁视频网站| 九七人妻一区二区三区| 日本啪啪一进一出视频| 熟女丝袜国产一区二区| 国产精品自拍视频合集| 天天色天天看天天综合网| 亚洲av午夜福利麻豆av| 一区日韩二区欧美三区国产| 看黄国产专区精品情侣| 永久黄网站色视频免费| 一区二区三区极品销魂| 久久久一本精品99久久精品66直播| 亚洲色精品VR一区二区| 国产av一区二区不卡| 少妇被爽到高潮的视频| 中文字幕乱码ⅱ大家伙| 国产高清内射一级一片| 自拍偷拍一区二区综合| 国产成人久久精品亚洲| 蜜臀午夜av一二三区| 亚洲蜜桃麻豆激情在线| 日韩中文字幕熟妇人妻| 精品免费国产一区二区三区四区五| 亚洲精品中文字幕久久久久下载| 丝袜美腿亚洲一区二区| 少妇人妻真实偷人精品| 蜜臀av中文人妻系列| 日韩高清av一区二区三| 国内一区二区三区精品|