首页
登录
职称英语
Soil quality is one of the most basic and perhaps least understood indicato
Soil quality is one of the most basic and perhaps least understood indicato
游客
2023-11-18
42
管理
问题
Soil quality is one of the most basic and perhaps least understood indicators of land health. Soil supports plant growth and represents the living reservoir that buffers the flows of water, nutrients, and energy through an ecosystem. Soil quality refers to the capacity of a soil to perform these beneficial functions and is determined by its texture, structure, water-holding capacity, porosity, organic matter content, and depth, among other properties. Because soils naturally vary in their capacity to perform these functions, we must tie our understanding of soil quality to landscapes and land use. We must understand soil quality for two important reasons: First, we must match our use and management of land to soil capability. Second, we must establish baseline understanding about soil quality so we can recognize ongoing trends. If soil quality is stable or improving, we have a good indicator that the ecosystem is sustainable. If soil quality is deteriorating, the larger ecosystem will almost certainly decline with it.
People describe soil types in all kind of ways such as beavy, light, sandy, clay, loam, poor or good. Soil scientists describe soil types by how much sand, silt and clay is present. This is called texture. It is possible to change the texture by adding different things to the soil. You can roughly estimate the texture of a soil by a simple method called" manual texturing", through determining the feel of a moist sample when robbed between the thumb and forefinger. If the soil sample is predominantly sand, it will feel very gritty, If it is predominantly silt, it will feel smooth or slippery to the touch. And if it’s predominant clay, it will feel sticky.
Particle size has a lot to do with a soil’s drainage and nutrient holding capacity. Sand is the largest particle and doesn’t hold many nutrients. Silt is a soil particle whose size is between sand and clay. When wet, silt feels smooth, but not sticky. Clay is smooth when dry and sticky when wet. Soils high in clay content are called heavy soils. Clay also can hold a lot of nutrients, but doesn’t let air and water throuhgh it well. To better understand how big these three soil particles are, think of them like this. If a particle of sand were the size of a basketball, then silt would be the size of a baseball, and clay would be the size of golf ball. [br] All of the following words are defined in the passage EXCEPT
选项
A、ecosystem.
B、soil quality.
C、texture.
D、manual texturing.
答案
A
解析
细节题。纵览全文可以看出第一段对soil quality下了定义;第二段对texture和manual texturing分别下了定义,而全文没有对ecosystem下定义,故选A
转载请注明原文地址:https://tihaiku.com/zcyy/3198039.html
相关试题推荐
Justasabookisoftenjudged______bythequalityandappearanceofitscover
Thoughthiscarismoreelegantinappearance,itsquality______thatlessfanc
Oneorperhapsmorepages______.A、aremissingB、aremissedC、ismissingD、ismis
Thescienceofmedicine,______progresshasbeenveryrapidlately,isperhapst
Ihavenoimpression______hewenthome,perhapsbybike.A、howB、whetherC、whenD
Howstricttutorsarewiththeirpupils______astrongimpactonthequalityof
Justasabookisoftenjudged______bythequalityandappearanceofitscover
Individualism,independence,andself-relianceareperhapsthemostdistin
Individualism,independence,andself-relianceareperhapsthemostdistin
Individualism,independence,andself-relianceareperhapsthemostdistin
随机试题
Heisnowaprominentlawyerinthiscitybuthe______asalesmanworkingfora
Ifyouknowwheretofindagoodplastic-freeshampoo,canyoutellJeanneH
属于PON接入技术描述范畴的有()A.CM B.OLT C.ON
乳牙或恒牙早失的临床表现不包括A.下乳尖牙早失常造成前牙深覆及中线偏移 B.第
儿茶酚胺症术前护理的关键措施是A.降低代谢率 B.心理护理 C.限制饮食
如图所示,梯形的上底和下底分别为5厘米、18厘米,两条腰分别为5厘米、12厘米,
关于社会工作者角色的说法,正确的是()。A.社会工作者为服务对象提供心理咨询,
期货公司风险监管指标优于预警标准并连续保持2个月的,风险预警期结束。()
患者,女,69岁。诊断为Ⅲ度深覆牙合,及缺失,义齿密合,但腭侧塑料基托反复折断。
在项目监理机构中落实从投资控制角度进行施工跟踪的人员、任务分工和职能分工,体现了
最新回复
(
0
)