草逼网址?,青青草国产精品日韩欧美,中文字幕乱码高清完整版,亚洲AV永久一区二区三区亚洲

Black sun screen dust screen

Canopy products > Shading net > Black sun screen dust screen

Black 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.



香蕉人在线香蕉人在线| 无码视频在线观看一区二区| 蜜臀久久精品久久久久久酒店?| 久久久久亚洲精品乱码按摩红桃| 国产精品免费精品自在线观看| 一炕四女被离换啪啪99精品一二三区| 中文字幕AV不卡电影网| 帮老师解开蕾丝奶罩吸乳网站 | 亚洲成人xxxxxxxx| 性爱视频网站国产传媒| 后入少妇白浆| xxxxx中文字幕| 嗯嗯嗯~啊啊啊www久久久 | 亚洲成人第一av| 精品国产aⅴ无码一区二区| 亚洲综合国产一区二区三区| 久久AV资源站| 成人毛片一区二区三区无码| 欧美人与物videos另类| 人体福利视频| 久久偷看各类wc女厕嘘嘘| 国产美女爆乳呻吟| 国产二汲大乱仑| 成人无码毛片在线网站| 日韩欧美性愛免费网| av大片在线无码永久免费 | 亚洲激情熟妇| 欧美日韩性爱视频| 婷婷 色五月 亚洲 色图| 都市激情 亚洲| 欧美乱妇无乱码大黄a片| 国产视频入口| 午夜视频久久久久一区| 色费女人18毛片a级毛片视频| 日本www视频| 苍井空最新无码 出| 男人的天堂亚洲区| 看免费国产乱伦视频| 国产精品中文字幕一区二区中文视频网| 久久99精品久久久久久婷婷2021| 久久午夜无码鲁丝片直播午夜精品 |